CN210275019U - High-shielding electromagnetic interference shielding film - Google Patents

Abstract

The utility model relates to a high shielding electromagnetic interference shielding film, which comprises a first release layer, a bottom coating, a black insulating layer, an adhesive layer, a conductive fiber layer, a conductive adhesive layer and a second release layer which are arranged in a stacking way; the black insulating layer is of a single-layer structure of a black polyimide film or a black ink layer, or a double-layer structure of a black polyimide film or a black ink layer superposed on the black polyimide film or the black ink layer, wherein the thickness of the black insulating layer is 3-30 mu m; the thickness of the conductive fiber layer is 5-30 μm; the thickness of the conductive adhesive layer is 3-30 mu m; the thickness of the adhesive layer is 3-12 mu m; the total thickness of the shielding film is 11 to 103 μm. The utility model discloses high shielding nature electromagnetic interference shielding film has that the flexibility is high, electrical property is good, the resistance to chemicals is good, shielding property is high, intensity is good, transmission loss is few, transmission quality is high, characteristics such as the degree of trust is good after that.

Description

High-shielding electromagnetic interference shielding film

Technical Field

The utility model relates to a shielding film, concretely relates to high shielding nature electromagnetic interference shielding film.

Background

Under the market demand that electronic and communication products tend to have multiple functions and be complicated, the structure of the circuit substrate needs to be lighter, thinner, shorter and smaller; functionally, powerful and high-speed signal transmission is required. Therefore, the circuit density is increased, the distance between the carrier circuits is closer, the operating frequency is higher and wider, and Electromagnetic Interference (EMI) is more and more serious if the circuit layout and the wiring are not reasonable, so that Electromagnetic Compatibility (EMC) must be effectively managed to maintain the normal signal transmission of the electronic product and improve the reliability. The characteristics of lightness, thinness and free bending make the soft board have a great significance in the development of the portable information and communication electronic industry.

As electronic communication products are getting smaller, the flexible printed circuit board is driven to have more and more powerful functions, and on the other hand, as portable electronic products are moving to microminiature, and the demand of high-density flexible printed circuit board technology is also driven, under the condition that the function is required to be powerful, high-frequency, high-density and thin-line, shielding films for thin film type flexible printed circuit boards (FPCs) are proposed in the market at present, and are widely used in small electronic products such as mobile phones, digital cameras and digital cameras.

With the coming of the 5G era, the requirements of terminal products on the electromagnetic shielding film are higher and higher, and the electromagnetic shielding film has good application prospects in the high-end manufacturing fields of mobile communication, medical display, military electronics and the like in the future.

In view of the above, it is desirable to develop an electromagnetic shielding film with better shielding performance.

SUMMERY OF THE UTILITY MODEL

In order to overcome the above defects, the present invention provides a high shielding electromagnetic interference shielding film, in which the conductive fiber is used to replace the metal layer in the shielding film of the prior art, the conductive fiber can generate strong reflection action to the electromagnetic wave projected on the surface of the shielding film, it can make most of the radio frequency and microwave energy reflected or absorbed, the transmission component is very small, thereby obtaining very large shielding attenuation.

The utility model discloses a solve the technical scheme that its technical problem adopted and be:

a high-shielding electromagnetic interference shielding film comprises a first release layer, a bottom coating, a black insulating layer, an adhesive layer, a conductive fiber layer, a conductive adhesive layer and a second release layer which are arranged in a stacked mode;

wherein the thickness of the black insulating layer is 3-30 μm;

the thickness of the conductive fiber layer is 5-30 μm;

the thickness of the conductive adhesive layer is 3-30 mu m;

the thickness of the adhesive layer is 3-12 mu m;

the total thickness of the shielding film is 11-103 μm, preferably 15-67 μm.

Preferably, the black insulating layer is a black polyimide film 11 or a black ink layer 12, and the thickness of the black insulating layer is 3 to 9 μm.

Preferably, the black insulating layer is of a double-layer structure and is formed by compounding a black polyimide layer and a black ink layer, and the thickness of the black insulating layer is 3-9 microns.

Preferably, the black ink layer is an ink layer made of at least one of epoxy resin, acrylic resin, urethane resin, silicone rubber resin, parylene resin, and bismaleimide resin, and the ink layer contains a flame retardant compound of at least one of halogen, phosphorus, nitrogen, and boron.

Preferably, the adhesive layer 30 is an epoxy glue added with carbon black, and the thickness of the adhesive layer is 3-6 μm.

Preferably, the material of the bottom coating is white or gray ink; and adding a dopant into the base coat, wherein the dopant is at least one of titanium dioxide, silicon dioxide, aluminum oxide, aluminum hydroxide and calcium carbonate.

Preferably, the conductive fiber layer is a pure metal fiber layer or a metallized fiber layer, the pure metal fiber layer is a copper fiber layer, an aluminum fiber layer or a lead fiber layer, the metallized fiber layer adopts polyester fiber cloth as a base material, and a metal coating is plated on the base material, and the metal coating is at least one of copper, nickel, cobalt, tin, silver, iron and gold coatings.

Preferably, the thickness of the conductive adhesive layer is 5-15 μm, and the conductive adhesive layer is one of the following two structures:

the conductive adhesive layer is a single-layer conductive adhesive layer with conductive particles or a single-layer conductive adhesive layer without conductive particles;

the conductive adhesive layer is of a double-layer structure and is formed by laminating an adhesive layer without conductive particles and a conductive adhesive layer with conductive particles, wherein the adhesive layer without conductive particles is adhered between the conductive fiber layer and the conductive adhesive layer with conductive particles.

Preferably, the first release layer and the second release layer are in one of the following three structures:

the release layer is a release film, the thickness of the release film is 25-100 mu m, and the release film is at least one of a PET fluoroplastic release film, a PET silicone-containing release film, a PET matte release film and a PE release film;

and secondly, the release layer is release paper, the thickness of the release paper is 25-130 mu m, and the release paper is PE laminating paper.

And the release layer is a low-adhesion carrier film, the thickness of the carrier film is 25-100 mu m, and the carrier film is a polyethylene terephthalate film, a polyethylene film or a polypropylene film.

The utility model has the advantages that:

1) the utility model discloses form one deck priming coat on the surface of black insulating layer, the priming coat is very thin, and thickness can be ignored, adds the adulterant in order to improve the surface roughness of insulating layer in the priming coat, through particle size, kind and content etc. of adjustment adulterant, can obtain required (such as glossiness, fire resistance, hardness or cost etc.) product, makes this product have better mechanical properties, electrical property and maneuverability etc.; meanwhile, as the dopant is added into the bottom coating, the black fog surface characteristic of the black insulating layer cannot be damaged, the hardness of the surface of the insulating layer is improved, the surface scratch is prevented, the bottom coating can protect the insulating layer from being easily corroded by chemical reagents in downstream processing procedures, and the weather resistance of the insulating layer is improved;

2) the utility model discloses can adopt double-deck black insulating layer, including black polyimide layer and black printing ink layer, its water absorption rate of black polyimide layer is extremely low, and the aqueous vapor is difficult to the invasion, also has splendid degree of reliability under the high humidity environment of high temperature, and added certain fire retardant in the printing ink layer, therefore this product has that electrical characteristic is good, the resistance to chemical is good, shielding property is high, the strength of adhesion is good, transmission loss is few, transmission quality is high, the degree of trust is good, characteristics such as fire resistance height; meanwhile, the double-layer insulating layer is adopted, so that the double-layer insulating layer has good hardness, mechanical strength and flexing resistance, and the design of the double-layer insulating layer can solve the problem of pin holes on the surface caused by uneven coating in the manufacturing process;

3) the utility model adopts the conductive fiber layer to replace the traditional metal layer, the conductive fiber layer has excellent flexibility and wear resistance, the product reliability and shielding performance can be improved, the oxidation resistance and conductivity can be improved, the thickness is more than 5um, and the shielding rate of more than 70dB or even higher can be reached; the conductive fiber can generate strong reflection action on the electromagnetic wave projected on the surface of the conductive fiber, most of radio frequency and microwave energy can be reflected or absorbed by the conductive fiber, the transmission component is extremely small, so that great shielding attenuation is obtained, and the pollution of the environmental electromagnetic wave radiation can be obviously eliminated through the local space protected by the conductive fiber; the conductive fiber layer has good mechanical properties, high fracture specific strength and tensile specific modulus, good bending resistance and good toughness; the conductive material has good conductivity, can prevent static electricity, has high temperature resistance, is an important material for preventing electromagnetic radiation, conducting and transmitting electric signals, can achieve good electromagnetic wave shielding effect, and has wide application in the aspects of military affairs, aviation, communication, confidential shielding environment and the like; compared with the traditional metal layer, the metal layer has better flexibility, bending resistance and toughness;

4) the utility model discloses increased the adhesion agent layer between black insulating layer and conductive fiber layer, both be convenient for make closely laminating between black insulating layer and the conductive fiber layer, prevent again that the phenomenon of concave-convex face can appear when directly laminating insulating layer and conductive fiber layer, this is because the conductive fiber layer surface is uneven itself, and when contacting the adhesion agent layer conductive fiber layer, because the adhesion agent layer has certain flexibility, consequently can hold the concave-convex face on the conductive fiber layer surface, rethread adhesion agent layer and insulating layer laminating, thereby eliminated the phenomenon of concave-convex face;

5) the conductive adhesive layer of the utility model can be a double-layer structure formed by laminating a layer of adhesive layer without conductive particles and a layer of conductive adhesive layer with conductive particles, and the adhesive layer can increase the binding force between the conductive fiber layer and the conductive adhesive layer with conductive particles; preferably, after the flexible printed circuit board is laminated on the FPC in the downstream process, the conductive particles are pierced through the thinned adhesive layer due to the hot pressing of the resin material and are directly conducted with the conductive fiber layer, so that the conductive fiber layer is directly contacted and conducted with the grounding wire on the printed circuit board, and the grounding wire on the flexible printed circuit board forms a conducting circuit;

6) the utility model discloses an among the conductive adhesive layer, accessible control conductive particle's particle diameter, kind and content obtain required product, for example with lower costs, the conductivity is better, processing operability is more excellent etc. because the utility model discloses an contain at least one kind in inorganic substance powder silica, titanium dioxide, aluminium oxide, aluminium hydroxide and the calcium carbonate among the conductive adhesive layer, so have extremely low water absorption rate, can be as low as 0.01-0.9%, have higher reliability under the high temperature and high humidity condition.

Drawings

Fig. 1 is a schematic structural view of the present invention;

fig. 2 is a schematic structural diagram of another embodiment of the present invention;

in the figure: 10-black insulating layer, 11-black polyimide layer, 12-black ink layer, 20-bottom coating layer, 30-adhesive layer, 40-conductive fiber layer, 50-conductive adhesive layer, 60-first release layer and 70-second release layer.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

As shown in fig. 1, a high-shielding electromagnetic interference shielding film is characterized in that: the adhesive comprises a first release layer 60, a bottom coating layer 20, a black insulating layer 10, an adhesive layer 30, a conductive fiber layer 40, a conductive adhesive layer 50 and a second release layer 70 which are arranged in a stacked manner;

wherein the thickness of the black insulating layer is 3-30 μm;

the thickness of the conductive fiber layer is 5-30 μm;

the thickness of the conductive adhesive layer is 3-30 mu m;

the thickness of the adhesive layer is 3-12 mu m;

the total thickness of the shielding film is 11-103 μm, preferably 15-67 μm.

As shown in fig. 2, the black insulating layer has a double-layer structure and is formed by combining a black polyimide layer and a black ink layer, and the thickness of the black insulating layer is 3 to 9 μm. The black insulating layer can also be a single-layer structure of a black polyimide film 11 or a black printing ink layer 12, and the thickness of the black insulating layer is 3-9 microns. The black polyimide layer has extremely low water absorption rate, is not easy to invade by water vapor, has excellent reliability under the high-temperature and high-humidity environment, and the electromagnetic shielding film has the characteristics of good electrical property, good chemical resistance, high shielding performance, good bonding strength, less transmission loss, high transmission quality, good reliability and the like; the problems of flame resistance and flame retardance can be solved by adding the flame-resistant compound in the ink layer; the double-layer structure can combine the advantages of the black polyimide and the black ink layer; the main effect of black insulating layer is insulating, so the utility model discloses when the insulating layer can play insulating effect, as far as possible with the thickness attenuate of insulating layer to let the product reach certain slim advantage, black PI layer and black printing ink layer do not have the injecing of specific upper and lower structure in the bilayer structure. The black ink layer is made of at least one of epoxy resin, acrylic resin, urethane resin, silicone rubber resin, poly-p-xylylene resin and bismaleimide resin, and the ink layer contains a compound with flame retardance of at least one of halogen, phosphorus, nitrogen and boron, so that the flame-retardant and flame-retardant performances of the shielding film are improved.

The adhesive layer 30 is an epoxy glue added with carbon black, and the thickness of the adhesive layer is 3-6 μm. Increased the adhesion agent layer between black insulating layer and conductive fiber layer, both be convenient for make closely laminating between black insulating layer and the conductive fiber layer, the phenomenon of the concave-convex face can appear when preventing directly laminating insulating layer and conductive fiber layer again, this is because conductive fiber layer surface itself is unsmooth, and when will adhesion agent layer contact conductive fiber layer, because the adhesion agent layer has certain flexibility, consequently can hold the concave-convex face on conductive fiber layer surface, rethread adhesion agent layer and insulating layer laminating, thereby the phenomenon of concave-convex face has been eliminated. The adhesive is generally a conventional epoxy system adhesive, wherein carbon black is added for dispersion, the addition of the carbon black is beneficial to improving the insulativity of the insulating layer and can play a better light shading effect, and the adhesive can facilitate the subsequent preparation process.

The bottom coating is made of white or gray ink; and adding a dopant into the base coat, wherein the dopant is at least one of titanium dioxide, silicon dioxide, aluminum oxide, aluminum hydroxide and calcium carbonate. The primer layer is very thin and the thickness of the primer layer can be ignored, the purpose of the primer layer is to add dopants to improve the surface roughness of the insulating layer, the prior art directly adds dopants into the black insulating layer to reduce the mechanical properties such as tensile strength and elongation of the black insulating layer, and the dopants are used for improving the gloss value of the surface of the black insulating layer so that the gloss value is controlled within the range of 0-60 degrees (measured by a gloss meter with an angle of 60 degrees). Because the base coat is doped with a plurality of inorganic substances, the base coat is used as the exposed surface of the product and has good mechanical property, friction resistance, aging resistance and chemical resistance; meanwhile, the surface gloss value is reduced, good scattering and extinction effects can be achieved, light penetration is reduced, the black fog surface characteristic of the insulating layer is guaranteed not to change, and the insulating layer is protected to a certain extent.

The conductive fiber layer is a pure metal fiber layer or a metallized fiber layer, the pure metal fiber layer is a copper fiber layer, an aluminum fiber layer or a lead fiber layer, the metallized fiber layer adopts polyester fiber cloth as a base material, and a metal coating is plated on the base material, and the metal coating is at least one of copper, nickel, cobalt, tin, silver, iron and gold coatings. The pure metal fiber is metal fiber with essential significance and is fiber made of metal material. The fiber is prepared by utilizing the conductive performance of metal and can reach the thickness of micron level. The main metal types of the pure metal fiber comprise copper, aluminum, lead and the like, the preparation method comprises a direct wire drawing method, a cutting method, a spinning method and the like, and the pure metal fiber has two weaving forms of plain woven fabric and non-woven fabric;

metallized fiber: the conductive fiber cloth is prepared by using organic fiber cloth (commonly used polyester fiber cloth) as a base material, pre-treating the base material, and plating a metal plating layer on the base material to ensure that the base material has metal characteristics. The metal layer can be a single metal layer of any one of copper, nickel, cobalt, tin, silver, iron and gold, or a double metal layer of nickel plating, copper conductive cloth, nickel plating, gold conductive cloth, or a triple metal layer of nickel plating, copper, silver conductive cloth, preferably a copper-nickel and copper-silver type metal composite layer, and the metal layer processing mode can be one or more of sputtering, evaporation, water plating and the like. Metallized fiber is prepared in two ways: firstly, plating metal on an organic fiber (silk thread) substrate, and then weaving to form a plain woven cloth or a non-woven cloth; secondly, the organic fiber is woven into plain weave cloth or non-woven cloth, and then a metal layer is plated on the surface of the plain weave cloth or the non-woven cloth;

the conductive fiber layer has excellent flexibility and wear resistance, can improve the reliability and shielding performance of products, can improve the oxidation resistance and conductivity, and can reach a shielding rate of more than 70dB or even higher when the thickness is more than 5 um; the function of the conductive fiber layer shows the conduction performance, the traditional electromagnetic shielding film adopts a metal coating to perform the shielding function, and the thin metal layer may not achieve the expected conduction effect and shielding performance.

The thickness of the conductive adhesive layer is 5-15 mu m, and the conductive adhesive layer is one of the following two structures:

the conductive adhesive layer is a single-layer conductive adhesive layer with conductive particles or a single-layer conductive adhesive layer without conductive particles;

the conductive adhesive layer is of a double-layer structure and is formed by laminating an adhesive layer without conductive particles and a conductive adhesive layer with conductive particles, wherein the adhesive layer without conductive particles is adhered between the conductive fiber layer and the conductive adhesive layer with conductive particles. The thickness of the conductive adhesive layer is used for forming a conducting circuit with the grounding wire on the flexible printed circuit board, and the resin is completely crosslinked and cured for a period of time to maintain good electrical property and mechanical property, so that the grounding impedance value of the flexible printed circuit board is reduced, and the purpose of reducing electromagnetic wave interference is achieved. The resin material of the conductive adhesive layer is at least one of epoxy resin, acrylic resin, urethane resin, silicone rubber resin, poly-p-xylylene resin, bismaleimide resin and polyimide resin. The conductive adhesive layer contains at least one of inorganic substance powder silicon dioxide, titanium dioxide, aluminum oxide, aluminum hydroxide and calcium carbonate. The water absorption rate of the conductive adhesive layer is between 0.01% and 0.9%. The particle size of the conductive particles in the conductive adhesive layer is 3-12 μm, and the weight percentage of the conductive particles in the total solid content of the conductive adhesive layer is 5-50%; the conductive particles of the conductive adhesive layer are at least one of copper, silver, nickel, tin, gold, palladium, aluminum, chromium, titanium, zinc and carbon, or at least one of nickel gold, gold and silver, copper nickel, copper silver, nickel silver and copper nickel gold.

The conductive adhesive and the conductive fiber layer are of a matched structure, and the conductive fiber layer cannot be directly adhered to the base material, so that the conductive adhesive with conductive metal particles is added, the conductive adhesive is embedded into gaps of the conductive fibers in the pressing process, and the conductive metal particles are in metal contact with the conductive cloth to form a power connection and conduction function.

The first release layer and the second release layer are one of the following three structures:

the release layer is a release film, the thickness of the release film is 25-100 mu m, and the release film is at least one of a PET fluoroplastic release film, a PET silicone-containing release film, a PET matte release film and a PE release film;

and secondly, the release layer is release paper, the thickness of the release paper is 25-130 mu m, and the release paper is PE laminating paper.

And the release layer is a low-adhesion carrier film, the thickness of the carrier film is 25-100 mu m, and the carrier film is a polyethylene terephthalate film, a polyethylene film or a polypropylene film. The second release layer is positioned below the conductive adhesive layer and used for protecting the adhesive layer from being stained with dirt and is not adhered to the release layer surface during rolling, and the product is adhered to the substrate and then is peeled off from the release layer.

A method for preparing a high-shielding electromagnetic interference shielding film, which is one of the following methods:

the method comprises the following steps: the method comprises the following steps:

step 1: the primer layer 20 is coated on the first release layer 60,

step 2: a black insulating layer 10 is coated on the undercoat layer,

and step 3: coating an adhesive layer 30 on the black insulating layer, attaching a conductive fiber layer 40 on the adhesive layer to obtain a semi-finished product I,

and 4, step 4: coating the conductive adhesive layer 50 on the second release layer 70 to obtain a semi-finished product II,

and 5: mutually attaching the conductive adhesive layer in the semi-finished product II and the conductive fiber layer in the semi-finished product I to obtain a finished shielding film;

the second method comprises the following steps: the method comprises the following steps:

step 1: the primer layer 20 is coated on the first release layer 60,

step 2: coating a black insulating layer 10 on the bottom coating to obtain a semi-finished product I,

and step 3: coating a conductive adhesive layer 50 on one side of the conductive fiber layer 40, attaching a second release layer 70 on the conductive adhesive layer,

and 4, step 4: coating the other side of the conductive fiber layer 40 with an adhesive layer 30 to obtain a semi-finished product II,

and 5: attaching the adhesive layer 30 in the semi-finished product II to the black insulating layer 10 in the semi-finished product I to obtain a finished shielding film;

the third method comprises the following steps: the method comprises the following steps:

step 1: the primer layer 20 is coated on the first release layer 60,

step 2: coating a black insulating layer 10 on the bottom coating to obtain a semi-finished product I,

and step 3: coating an adhesive layer 30 on one surface of the conductive fiber layer, attaching the black insulating layer 10 in the semi-finished product I on the adhesive layer to obtain a semi-finished product II,

and 4, step 4: finally, coating a conductive adhesive layer 50 on the other surface of the conductive fiber layer in the semi-finished product II, and attaching a second release layer 70 on the conductive adhesive layer to obtain a finished shielding film;

the method four comprises the following steps: the method comprises the following steps:

step 1: coating the primer layer 20 on the first release layer 60;

step 2: coating a black insulating layer 10 on the undercoat layer;

and step 3: coating an adhesive layer 30 on the black insulating layer, and attaching one surface of the conductive fiber layer 40 to the adhesive layer;

and 4, step 4: and coating a conductive adhesive layer 50 on the other surface of the conductive fiber layer, and attaching a second release layer 70 on the conductive adhesive layer to obtain the finished shielding film.

For convenience of understanding, the advantages of the present invention are shown in table 1, which is a comparison result between the embodiments and the comparative examples in the performance indexes such as resistance, peel strength and shielding performance tests. Wherein, the conductive layer in the examples 1-3 and 7-9 is a pure metal fiber layer, the conductive layer in the examples 4-6 and 10-12 is a metallized fiber layer, and the conductive layer in the comparative example is a metal layer; the black insulating layers in examples 1, 3 and 5 were black polyimide layers, the black insulating layers in examples 2, 4 and 6 were black ink layers, and the black insulating layers in examples 1 to 12 were coated with primer layers; the EMI shielding film has the surface hardness of 3-4H, and has excellent shielding effect, and the surface hardness reaches 75dB @1GHz in a normal state.

Table 1:

in order to highlight the utility model discloses compare the reliability and the degree of trust of market product, carried out following test, table 2 is our test result:

table 2:

as can be seen from Table 1, when a finished product is made of a 3um single-layer insulating layer, the insulating property is slightly poor, and when the thickness of the insulating layer reaches 6um or more, the insulating property of the shielding film is greatly improved; in comparative examples 1 and 2, the metal layer is used as the conductive layer, and the performance such as insulation and shielding performance are not as good as those of the embodiment of the present invention, while in comparative example 2, when the thickness of the metal layer is 0.2um, the problem of on-resistance exists, and the shielding effect is not as good as that of the thick metal layer; it can be seen from table 1 that after 15um conductive fiber layer is added into the black insulating layer and the conductive adhesive layer, the high shielding rate of 80dB can be achieved, the high shielding rate of more than 70dB can be achieved under 9um, and the high shielding rate can be still maintained under double 85, which is obviously superior to the comparative example;

as can be seen from table 2, even in a severe environment, the shielding film of the present embodiment still has a very low on-resistance, and particularly, after being placed in a high-temperature and high-humidity environment of double 85 for 500 hours, the on-resistance still can be kept very low to maintain the shielding performance, and the shielding film has an excellent reliability and is significantly better than the comparative example.

The utility model discloses high shielding nature electromagnetic interference shielding film has that the flexibility is high, electrical characteristics is good, the resistance to chemicals is good, shielding property is high, intensity is good after that, transmission loss is few, transmission quality is high, characteristics such as the reliability is good, compares general electromagnetic shielding film and has higher transmission quality, makes it not disturbed between each other in very little space to replace general shielding film material.

It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several changes and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims (9)

1. A high-shielding electromagnetic interference shielding film, characterized in that: the adhesive comprises a first release layer (60), a bottom coating (20), a black insulating layer (10), an adhesive layer (30), a conductive fiber layer (40), a conductive adhesive layer (50) and a second release layer (70) which are arranged in a laminated manner;

wherein the thickness of the black insulating layer is 3-30 μm;

the thickness of the conductive fiber layer is 5-30 μm;

the thickness of the conductive adhesive layer is 3-30 mu m;

the thickness of the adhesive layer is 3-12 mu m;

the total thickness of the shielding film is 11 to 103 μm.

2. The high-shielding electromagnetic interference shielding film according to claim 1, wherein: the black insulating layer is a black polyimide film (11) or a black ink layer (12), and the thickness of the black insulating layer is 3-9 microns.

3. The high-shielding electromagnetic interference shielding film according to claim 1, wherein: the black insulating layer is of a double-layer structure and is formed by compounding a black polyimide layer and a black printing ink layer, and the thickness of the black insulating layer is 3-9 microns.

4. The high-shielding electromagnetic interference shielding film according to claim 2 or 3, wherein: the black ink layer is made of one of epoxy resin, acrylic resin, urethane resin, silicone rubber resin, poly-p-xylylene resin and bismaleimide resin.

5. The high-shielding electromagnetic interference shielding film according to claim 1, wherein: the adhesive layer (30) is an epoxy glue added with carbon black, and the thickness of the adhesive layer is 3-6 mu m.

6. The high-shielding electromagnetic interference shielding film according to claim 1, wherein: the material of the bottom coating is white or gray ink, a dopant is added into the bottom coating, and the dopant is one of titanium dioxide, silicon dioxide, aluminum oxide, aluminum hydroxide and calcium carbonate.

7. The high-shielding electromagnetic interference shielding film according to claim 1, wherein: the conductive fiber layer is a pure metal fiber layer or a metallized fiber layer, the pure metal fiber layer is a copper fiber layer, an aluminum fiber layer or a lead fiber layer, the metallized fiber layer adopts polyester fiber cloth as a base material, and a metal coating is plated on the base material, and the metal coating is one of copper, nickel, cobalt, tin, silver, iron and gold coatings.

8. The high-shielding electromagnetic interference shielding film according to claim 1, wherein: the thickness of the conductive adhesive layer is 5-15 mu m, and the conductive adhesive layer is one of the following two structures:

the conductive adhesive layer is a single-layer conductive adhesive layer with conductive particles or a single-layer conductive adhesive layer without conductive particles;

the conductive adhesive layer is of a double-layer structure and is formed by laminating an adhesive layer without conductive particles and a conductive adhesive layer with conductive particles, wherein the adhesive layer without conductive particles is adhered between the conductive fiber layer and the conductive adhesive layer with conductive particles.

9. The high-shielding electromagnetic interference shielding film according to claim 1, wherein: the first release layer and the second release layer are one of the following three structures:

the release layer is a release film, the thickness of the release film is 25-100 mu m, and the release film is a PET fluoroplastic release film, a PET silicone oil-containing release film, a PET matte release film or a PE release film;

secondly, the release layer is release paper, the thickness of the release paper is 25-130 mu m, and the release paper is PE laminating paper;

and the release layer is a low-adhesion carrier film, the thickness of the carrier film is 25-100 mu m, and the carrier film is a polyethylene terephthalate film, a polyethylene film or a polypropylene film.

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