WO2020020196A1 - Double-layer electromagnetic shielding film and manufacturing method therefor - Google Patents

Abstract

A double-layer electromagnetic shielding film, comprising a bearer film (1), a first insulated coating layer (2) applied to the bearer film (1), a second insulated coating layer (3) applied to the first insulated coating layer (2), a metal layer (4) compounded onto the second insulated coating layer (3), an electromagnetic wave shielding coating layer (5) applied to the metal layer (4), and a protective release film (6) provided on the electromagnetic wave shielding coating layer, wherein the bearer film (1) is a matte release film; the coating of the first insulated coating layer (2) is abrasion resistant acrylate coating or polyurethane coating, the abrasion resistance is greater than 1,000 times, and the thickness is 1-2μm; the coating of the second insulated coating layer (3) is highly-filled and high-toughness acrylate coating, or polyurethane coating, or rubber coating, the number of bending-resistant times is greater than 80,000, and the thickness is 2-7μm; the metal layer (4) is a thin film made of rolled metal foil and has the thickness of 3-9μm. The double-layer electromagnetic shielding film has better toughness, bending-resistance and product smoothness, and a better shielding effect.

Description

Double-layer electromagnetic shielding film and preparation method thereof Technical field

The invention relates to the technical field of electromagnetic shielding, in particular to a double-layer electromagnetic shielding film and a preparation method thereof.

Background technique

In the flexible printed circuit board (FPC) industry, with the upgrading of electronic devices such as smart phones and Ipads, the requirements for electromagnetic shielding have become higher and higher. Due to the processing technology and use requirements of FPC, the electromagnetic shielding film used on FPC must meet the following requirements: high temperature (180 ° C, several hours, 270 ° C, short time) high pressure (12MPa), flexibility and resistance to bending, constant temperature for 1000h Constant humidity (85 ° C temperature, 85% humidity), resistant water (acid, alkali, organic solvents), resistant to ultrasonic cleaning.

In the prior art, the electromagnetic shielding film has the following problems: (1) the insulating layer of the electromagnetic shielding film uses ink. Due to the low molecular weight of the ink, the high proportion of the filler, and the high crosslink density, the ink is printed on the ordinary carrier film, and the volume of the curing reaction is Large shrinkage, due to the brittle and hard characteristics of the ink itself, it will cause the electromagnetic shielding film produced by the ink to be hard and brittle and not resistant to bending; used in the FPC industry, resulting in the flexibility and bending resistance of the electromagnetic shielding film Poor properties and poor product flatness; when the carrier film is torn, the ink is liable to stick to the carrier film; the ink itself is relatively brittle and prone to micro-cracks, resulting in the infiltration of the drug solution during the subsequent processing of the FPC, resulting in product scrap. (2) The shielding layer of the electromagnetic shielding film uses a metal shielding layer to improve the shielding effect. Generally, vacuum sputtering or electroplating is used to form a metal layer on the insulating layer. The thickness of the metal layer formed by this method is limited, the efficiency is low, and The electroplated metal layer is prone to columnar crystals, making the metal layer non-ductile. In the subsequent complicated high-temperature and high-pressure operation process of FPC, cracks and oxidation are prone to occur, which will reduce the shielding performance and even lose the shielding performance. In the subsequent reflow soldering process, it is easy to blister and delaminate, which can not meet the requirements of FPC for breakability, high temperature and pressure resistance, and resistance to water impact. (3) The shielding performance of shielding film made of ordinary conductive adhesive is difficult to reach 60dB. With the development of information technology, the commercial application of 5G communication often requires shielding performance of FPC greater than 60dB, or even 80dB. The ordinary shielding film is completely complete. It is impossible to meet the requirements of the FPC industry for high shielding performance.

Summary of the Invention

The technical problem to be solved by the present invention is to provide a double-layer electromagnetic shielding film and a double-layer electromagnetic shielding film and a preparation method thereof, which have better flexibility, bending resistance, product flatness and shielding effect.

In order to solve the above technical problems, the present invention provides a double-layer electromagnetic shielding film including a carrier film, a first insulating coating layer coated on the carrier film, and a second insulating coating layer coated on the first insulating coating layer. A metal layer compounded on the second insulating coating layer, an electromagnetic wave shielding coating applied on the metal layer, and a release protective film provided on the electromagnetic wave shielding coating;

The carrier film is a matte release film; the coating of the first insulating coating layer is an abrasion-resistant acrylate coating or a urethane coating, which has abrasion resistance greater than 1,000 times and a thickness of 1 to 2 μm; the second insulation The coating of the coating layer is a high-filling, high-toughness acrylate coating or a polyurethane coating or a rubber coating with a bending resistance of more than 80,000 and a thickness of 2 to 7 μm; the metal layer is made of rolled metal foil and has a thickness of 3 to 9 μm Thin film.

The electromagnetic wave shielding coating is a reflective shielding coating; a coating of the reflective shielding coating includes a reflective layer matrix resin and a metal filler, the reflective layer matrix resin is an acrylic type, a polyurethane type, or a rubber type, and the metal The filler is sheet-shaped silver-clad glass or sheet-shaped silver-coated copper powder or leaf-shaped silver-coated copper powder or dendritic silver-coated copper powder; the size of the metal filler in the thickness direction is 1 to 2 μm, the plane size is 3 to 9 μm, and the shape of the leaf is The metal filler has 3 to 5 branches; the mass ratio of the reflective layer matrix resin of the reflective shielding coating to the metal filler is 1: 1.5 to 1: 5.

The invention also provides a double-layer electromagnetic shielding film, which comprises a carrier film, a first insulating coating layer coated on the carrier film, a second insulating coating layer coated on the first insulating coating layer, and a second insulating coating. A metal layer on a paint layer, an electromagnetic wave shielding coating applied on the metal layer, and a release protective film provided on the electromagnetic wave shielding coating;

The carrier film is a matte release film; the coating of the first insulating coating layer is an abrasion-resistant acrylate coating or a urethane coating, which has abrasion resistance greater than 1,000 times and a thickness of 1 to 2 μm; the second insulation The coating of the coating layer is a high-filling, high-toughness acrylate coating or a polyurethane coating or a rubber coating with a bending resistance of more than 80,000 and a thickness of 2 to 7 μm; the metal layer is made of rolled metal foil and has a thickness of 3 to 9 μm Thin film

The electromagnetic wave shielding coating is an absorption-type shielding coating; the absorption-type shielding coating comprises 10 to 50 parts of the matrix resin of the absorption layer, one or more of 10 to 30 parts of polypyrrole, polyaniline, and polythiophene, 20 to 80 parts of one or more of acetylene carbon black, silicon carbide, and ferrite are mixed, and the matrix resin of the absorption layer is acrylic type, polyurethane type, or rubber type.

The invention also provides a double-layer electromagnetic shielding film, which comprises a carrier film, a first insulating coating layer coated on the carrier film, a second insulating coating layer coated on the first insulating coating layer, and a second insulating coating. A metal layer on a paint layer, an electromagnetic wave shielding coating applied on the metal layer, and a release protective film provided on the electromagnetic wave shielding coating;

The carrier film is a matte release film; the coating of the first insulating coating layer is an abrasion-resistant acrylate coating or a urethane coating, which has abrasion resistance greater than 1,000 times and a thickness of 1 to 2 μm; the second insulation The coating of the coating layer is a high-filling, high-toughness acrylate coating or a polyurethane coating or a rubber coating with a bending resistance of more than 80,000 and a thickness of 2 to 7 μm; the metal layer is made of rolled metal foil and has a thickness of 3 to 9 μm Thin film

The electromagnetic wave shielding coating includes a reflective shielding coating and an absorptive shielding coating provided on the reflective shielding coating; a coating of the reflective shielding coating includes a reflective layer matrix resin and a metal filler, and the reflective layer The matrix resin is an acrylic type, a polyurethane type, or a rubber type, and the metal filler is sheet-shaped silver-clad glass or sheet-shaped silver-coated copper powder or leaf-shaped silver-coated copper powder or dendritic silver-coated copper powder; The direction dimension is 1 to 2 μm, the plane dimension is 3 to 9 μm, the leaf-like metal filler has 3 to 5 branches; the mass ratio of the reflective layer matrix resin of the reflective shielding coating to the metal filler is 1 : 1.5 ~ 1: 5; The absorption-type shielding coating includes 10-50 parts of the base layer resin of the absorption layer, 10-30 parts of one or more of polypyrrole, polyaniline, polythiophene, acetylene black, and silicon carbide 20 to 80 parts of one or more ferrites are mixed and made, and the matrix resin of the absorption layer is acrylic type, polyurethane type or rubber type.

As a preferred aspect, the metal layer is a rolled copper foil, a rolled aluminum foil, or a rolled silver foil.

As a preferred mode, the reflective layer matrix resin of the reflective shielding coating is an acrylic matrix resin, and the formula is as follows:

(1) Take 7 to 15 parts of acrylic acid, 35 to 50 parts of acrylonitrile, 20 to 30 parts of butyl acrylate, and 20 to 30 parts of hydroxyethyl acrylate by weight, and react the above raw materials at 60 to 80 ° C for 10 to 20 hours. Acrylic resin III was obtained through polymerization; acrylic resin III was obtained with a molecular weight of 50,000 to 70,000;

(2) Take 50 to 70 parts of the above-mentioned acrylic resin III by weight, one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy polyfunctional epoxy resin 10 to 30. Parts, 5 to 10 parts of dicyandiamide, and 5 to 10 parts of diaminodiphenyl sulfone, and uniformly stirred to obtain an acrylic reflective layer base resin.

As a preferred mode, the reflection-layer matrix resin of the reflection-type shielding coating is a polyurethane-type matrix resin, and the formula is as follows:

(1) Take a polyester polyol with a molecular weight of 4000 to 6000, and one or more of toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, and the molar ratio of functional groups is 1.3 to 1.5: 1. , Prepolymerization, prepolymerization, adding an organic tin catalyst, and reacting at 50 to 70 ° C. for 8 to 12 hours to obtain a hydroxyl-terminated prepolymer.

(2) Take 60 to 80 parts of the above-mentioned hydroxyl-terminated prepolymer, 1 to 10 parts of hexamethylene diisocyanate trimer or isophorone diisocyanate trimer by weight, bisphenol A epoxy resin, bis 10 to 20 parts of one or more of a phenol F type epoxy resin and a phenolic epoxy polyfunctional epoxy resin, and 10 to 20 parts of diaminodiphenyl sulfone, uniformly stirred to obtain a polyurethane-type reflective layer matrix resin.

As a preferred mode, the reflective layer matrix resin of the reflective shielding coating is a rubber-type reflective layer matrix resin, and the formula is as follows:

30 to 60 parts of carboxyl or hydroxybutyronitrile rubber, 30 to 50 parts of one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy polyfunctional epoxy resin by weight 5-10 parts of dicyandiamide and 10-20 parts of diaminodiphenyl sulfone, stir well to prepare a rubber-type reflective layer matrix resin.

As a preferred mode, the matrix resin of the absorption layer of the absorption-type shielding coating is an acrylic resin, and the formula is as follows:

(1) Take 5 to 10 parts of acrylic acid, 30 to 60 parts of acrylonitrile, 20 to 40 parts of hydroxyethyl acrylate, and 10 to 20 parts of n-butyl methacrylate. Add persulfate initiator based on the weight percentage of the reactant. 60 ~ 80 ° C, reaction for 10 ~ 20h, acrylic resin IV is prepared by emulsion polymerization of the above raw materials;

(2) Take 60 to 80 parts of the above-mentioned acrylic resin IV by weight, one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy polyfunctional epoxy resin, or 10 to 30 Parts, 5 to 10 parts of diaminodiphenyl sulfone, and uniformly stirred to obtain an acrylic absorbent layer base resin.

As a preferred mode, the matrix resin of the absorption layer of the absorption-type shielding coating layer is a polyurethane-type resin, and the formula is as follows:

(1) Take a polyester polyol with a molecular weight of 4000 to 6000, and one or more of toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, and the functional group molar ratio of 1.1 to 1.2: 1 , Prepolymerization, adding an organotin catalyst, and reacting at 50 to 70 ° C for 8 to 12 hours to obtain a hydroxyl-terminated prepolymer;

(2) Take 60 to 80 parts of the above-mentioned hydroxyl-terminated prepolymer, 1 to 10 parts of hexamethylene diisocyanate trimer or isophorone diisocyanate trimer by weight, bisphenol A epoxy resin, bis 10 to 20 parts of one or more of a phenol F type epoxy resin and a phenolic epoxy multifunctional epoxy resin, and 5 to 10 parts of diaminodiphenyl sulfone, and uniformly stirred to obtain a polyurethane-type absorption layer matrix resin.

As a preferred mode, the matrix resin of the absorption layer of the absorption-type shielding coating layer is a rubber-type resin, and the formula is as follows:

30 to 60 parts of carboxyl or hydroxybutyronitrile rubber, 30 to 50 parts of one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy polyfunctional epoxy resin by weight 5-10 parts of dicyandiamide and 10-20 parts of diaminodiphenyl sulfone, stir well to prepare a rubber-type absorption layer matrix resin.

In a preferred manner, the coating of the first insulating coating layer is an acrylate coating, and the formula is as follows:

(1) Take 3 to 10 parts of acrylic acid, 10 to 30 parts of methyl acrylate, 30 to 60 parts of acrylonitrile, 10 to 30 parts of butyl acrylate, and 5 to 10 parts of isobornyl acrylate by weight. Reaction for 30-60 hours. Acrylic resin I is prepared through emulsion or solution or bulk polymerization.

(2) Take the above acrylic resin I, and add 10% to 20% pigment carbon black, 3 to 10% titanium dioxide, 5 to 15% silicon oxide, and 1 to 5% acrylic curing agent to the acrylic resin I in a weight ratio. Stir evenly to produce a wear-resistant coating for the first insulation coating layer, with abrasion resistance exceeding 1,000 times.

In a preferred manner, the coating of the first insulating coating layer is a polyurethane coating, and the formula is as follows:

(1) Take one or more of polyester polyols, polyether polyols, and hydroxyl-terminated polycarbonates with a molecular weight of 1000 to 2000, and toluene diisocyanate, diphenylmethane diisocyanate, xylylene diamine One or more of isocyanates are added at a functional group molar ratio of 1.1 to 1.3: 1, an organic tin catalyst is added, and the reaction is carried out at 40 to 60 ° C for 8 to 10 hours, and then heated to 80 to 100 ° C for 5 to 10 hours to synthesize a hydroxyl-terminated polyurethane. Resin I has a molecular weight of 10,000 to 30,000;

(2) Take the above polyurethane resin I, and add 10% to 20% pigment carbon black, 3 to 10% titanium dioxide, 5 to 15% silicon oxide, and 1 to 5% polyurethane curing agent to the polyurethane resin I in a weight ratio, and stir Uniform, the first insulation coating layer of abrasion-resistant coating is produced, and the abrasion resistance meets more than 1,000 times.

In a preferred manner, the coating of the second insulating coating layer is an acrylate coating, and the formula is as follows:

(1) Take 2 to 5 parts of acrylic acid, 10 to 40 parts of ethyl acrylate, 30 to 60 parts of butyl methacrylate, and 5 to 10 parts of acrylonitrile by weight, and react at 40 to 55 ° C for 40 to 60 hours. Acrylic resin II is prepared by solution or bulk polymerization, and the molecular weight of acrylic resin II is greater than 150,000;

(2) Take the above-mentioned acrylic resin II, and add 10-30% organic elastic microspheres with a diameter of 1-7 μm to the acrylic resin II in a weight ratio to make a second high filling property, high toughness and good bending resistance. Acrylic paint for insulation coating layer; resistance to bending is greater than 80,000.

In a preferred manner, the coating of the second insulating coating layer is a polyurethane coating, and the preparation process is as follows:

(1) Take one or more of polyester polyol, polyether polyol, and hydroxyl-terminated polycarbonate with a molecular weight of 3000 to 5000, and one of hexamethylene diisocyanate and isophorone diisocyanate Or several kinds of functional groups with a molar ratio of 1.05 to 1.2: 1, adding an organotin catalyst, reacting at 40 to 60 ° C for 8 to 10 hours, and then heating to 80 to 100 ° C for 5 to 10 hours to synthesize a hydroxyl-terminated polyurethane resin II. ~ 60,000;

(2) Take the above-mentioned polyurethane rubber II, and add 10-30% organic elastic microspheres with a diameter of 1-7 μm to the polyurethane resin II according to its weight ratio, and stir evenly to obtain high filling, high toughness, and bending resistance. Good performance of the second insulating coating layer coating, the number of times of bending resistance is greater than 80,000.

In a preferred manner, the coating of the second insulating coating layer is a rubber coating, and the formula is as follows:

Take carboxyl nitrile rubber or hydroxybutyronitrile rubber with a molecular weight of 200,000 to 300,000, and add 10 to 30% of organic elastic microspheres with a diameter of 1 to 7 μm to the rubber coating by weight ratio to obtain high filling, high toughness, and resistance Good bendability The second insulation coating layer coating has a bending resistance greater than 80,000.

The invention provides a method for preparing a double-layer electromagnetic shielding film, which includes the following steps: first, A1, preparing a coating of a first insulating coating layer; A2, coating of a second insulating coating layer; A3, made of rolled metal foil Metal layer; A4, coating of electromagnetic wave shielding layer;

The second step, coating

A5. Remove oil and foreign matter on the inner surface of the carrier film roll;

A6. Coat the prepared first insulating coating layer on the inner surface of the carrier film roll with a thickness of 1 to 2 μm. The first insulating coating layer is cured by oven drying; the oven temperature is 60 to 120 ° C; the line speed is 5 to 30m. / min;

A7. Coat the prepared second insulating coating layer on the first insulating coating layer with a thickness of 2-7 μm, and dry the second insulating coating layer by oven drying; the oven temperature is 60 to 120 ° C; the line speed is 5 to 30m / min;

A8. The composite metal layer is passed through a laminator on the second insulating coating layer;

A9. Apply the prepared electromagnetic wave shielding coating on the metal layer with a thickness of 2 ~ 5μm and dry it in an oven. The oven temperature is 60 ~ 120 ℃; the line speed is 5 ~ 30m / min;

A10. Thermally attach a release protective film layer on the electromagnetic wave shielding layer;

A11. Rewind.

The invention provides a method for preparing a double-layer electromagnetic shielding film, which includes the following steps:

In the first step, B1, the coating of the first insulating coating layer is prepared; B2, the coating of the second insulating coating layer; B3, the metal layer made of rolled metal foil; B4, the coating of the electromagnetic wave shielding layer;

The second step,

B5. Remove oil and foreign matter on the inner surface of the carrier film roll;

B6. On the inner surface of the carrier film roll, apply the above-mentioned prepared first insulating coating layer and second insulating coating layer through a double-nozzle coating head at the same time, with thicknesses of 1 to 2 μm and 2 to 7 μm, respectively. Dry the oven to make the first insulation The coating layer and the second insulating coating layer are cured; the oven temperature is 60 to 120 ° C, and the line speed is 5 to 30 m / min;

B7. Compound metal layer through a laminator on the second insulating coating layer;

B8. Coat the prepared electromagnetic wave shielding layer on the release protective film layer and dry it in an oven. The oven temperature is 60 ～ 120 ℃; the line speed is 5 ～ 30m / min;

B9. The metal layer on the carrier film and the electromagnetic wave shielding layer on the release protective film layer are hot-pressed and compounded;

B10. Rewinding.

The invention relates to a double-layer electromagnetic shielding film and a method for preparing the same. Compared with the existing design, the invention has the following advantages: (1) The present invention uses a rolled metal foil made of silver, copper, or aluminum as a metal layer. Compound with insulating coating layer. Because the metal layer made of rolled metal foil has ductility, no cracks, oxidation, etc. will occur during the complicated high-temperature and high-pressure operation process of the FPC, which meets the FPC's resistance to breakage, high temperature and high pressure, and resistance to water. Performance requirements. In addition, the thickness of the metal foil is 3 to 9 μm, which is thicker than the thickness of a metal layer formed by vacuum sputtering or electroplating, so as to achieve a better shielding effect.

(2) The electromagnetic wave shielding layer is further coated on the metal layer to form a double-layer electromagnetic shielding film to improve the electromagnetic wave shielding effect. The shielding effect can reach more than 80dB and achieve high frequency and high conductance, which can be used in the fields of aviation, aerospace, military and other fields.

(3) The electromagnetic wave shielding layer is a reflective shielding coating or an absorption shielding coating or a composite film of both.

Among them, the metal filler in the reflective shielding coating is a sheet-like silver-clad glass or silver-coated copper powder, a leaf-like or dendritic silver-coated copper powder, and mixed with a resin to make a reflective-type shielding coating, sheet-like or leaf-like or branch The conductive fillers are overlapped with each other to achieve long-distance isotropic continuous conductive performance. The thickness of the conductive filler is 1 to 2 μm and the plane size is 3 to 9 μm. Furthermore, each leaf-like silver-clad copper There are 3 to 5 forks on the powder, which is more conducive to the overlap between each other. After the metal filler is activated, the electrical conductivity can be greatly reduced and improved.

Absorptive shielding coating. Adding absorbing materials, such as polyaniline, polypyrrole, polythiophene, acetylene black, silicon carbide, and ferrite, can absorb residual electromagnetic waves.

(4) In the present invention, the insulating layer of the shielding film is coated, including a first insulating coating layer and a second insulating coating layer. The carrier film is a matte release film. The coating has a large molecular weight, a low filler ratio, and is softer. Crosslinking density Small, high temperature and pressure resistance after cross-linking, will not become brittle, will not crack, resistant to water impact. The first insulating coating layer is coated on the matte release carrier film. Due to the low surface energy of the matte release film, the coating cannot be well wetted on the surface of the release film. The unevenness can form a local air cushion between the release film and the coating layer to achieve the purpose of separating the release film from the insulating layer.

The first insulating coating layer of the shielding film of the present invention has abrasion resistance, and the abrasion resistance is more than 1,000 times, which plays a role of protecting the electromagnetic film. The second insulating coating layer uses a high filling and high toughness coating to ensure the product's bending resistance. , Bending resistance is greater than 80,000 times, making the overall shielding film flexible, bending resistance and product flatness better.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic longitudinal sectional view of Embodiment 1 of the present invention.

FIG. 2 is a schematic longitudinal section view of Embodiment 8 of the present invention.

FIG. 3 is a schematic longitudinal sectional view of Embodiment 15 of the present invention.

The reference signs are as follows:

1-carrier film, 2-first insulating coating layer, 3-second insulating coating layer, 4-metal layer, 5-electromagnetic wave shielding layer, 51-reflective shielding coating, 52-absorptive shielding coating, 6- Release protective film layer.

detailed description

Referring to FIG. 1, the double-layer electromagnetic shielding film of the present invention includes a matte carrier film 1 coated with a release agent 1, a first insulating coating layer 2 on the carrier film 1, and a second insulating coating layer on the first insulating coating layer 2. The layer 3 is a metal layer 4 compounded on the second insulating coating layer 3, an electromagnetic wave shielding coating 5 coated on the metal layer 4, and a release protective film 6 provided on the electromagnetic wave shielding coating 5.

The carrier film 1 is a matte film release agent, which solves the problem of separation between the insulating layer and the carrier film. That is, the matte release film has a thickness of 25 to 100 μm, and preferably 50 μm. The matte film is made of PET, PBT, PNT film, and the release agent is a silicone release film or a non-silicon release film, so that the release agent does not fall off.

As the paint of the first insulating paint layer 2, an acrylic paint or a polyurethane paint can be used, and the thickness is 1 to 2 μm.

As the coating material of the second insulating coating layer 3, an acrylic coating material, a urethane coating material, or a rubber coating material can be used, and the thickness is 2 to 7 μm.

The metal layer 4 is a rolled copper foil, a rolled aluminum foil, or a rolled silver foil, and has a thickness of 3 to 9 μm, and preferably 6 μm.

The electromagnetic shielding coating 5 is a reflective shielding coating 51 or an absorbing shielding coating 52 or a composite film layer of the reflective shielding coating 51 and the absorption shielding coating 52; wherein the thickness of the reflective shielding coating 51 is 5 -10 μm, the reflection-layer base resin of the reflection-type shielding coating 51 may be an acrylic coating, a polyurethane coating, or a rubber coating. The thickness of the absorptive shielding coating layer 52 is 2 to 5 μm. As the absorptive layer base resin of the absorptive shielding coating layer 52, an acrylic paint, a polyurethane paint, or rubber can be used.

The release protective film layer 6 is one of a PET release film, a PP release film, a PBT release film, and a release paper. The thickness of the release protective film is 25 to 100 μm, and preferably 50 μm.

The present invention is specifically described below in combination with specific embodiments.

Example 1

The electromagnetic wave shielding layer of the present invention is a reflective shielding coating. The coatings of the first insulating coating layer, the second insulating coating layer, and the reflective shielding coating are acrylic coatings. The manufacturing process of the double-layer electromagnetic shielding film can be as follows.

The first step is to prepare the first insulating coating layer, the second insulating coating layer, the reflective shielding coating coating, and the metal layer material, which can be prepared in the following order, but the scope of protection is not limited to the following A1, A2, A3, A4 Order.

A1. Prepare a first insulating coating layer coating;

(1) Take 7 parts of acrylic acid, 20 parts of methyl acrylate, 45 parts of acrylonitrile, 20 parts of butyl acrylate, and 7 parts of isobornyl acrylate through emulsion (or solution polymerization, bulk polymerization) polymerization to obtain acrylic resin I, by weight Compared with the addition of persulfate 0.3% to 1.2%, the acrylic resin I has a molecular weight of more than 100,000 at a temperature of 50 to 60 ° C and a reaction time of 30 to 60 hours.

(2) Take the above-mentioned acrylic resin I, and add 15% pigment carbon black, 7% titanium dioxide, 10% silicon oxide, 1 to 5% acrylic curing agent in acrylic resin I by weight ratio, stir evenly to obtain abrasion resistance Type first insulating coating layer coating. See Table 1 for performance.

A2, preparing a second insulating coating layer coating;

(1) Take 4 parts of acrylic acid, 25 parts of ethyl acrylate, 45 parts of butyl methacrylate, and 7 parts of acrylonitrile to prepare acrylic resin II by emulsion (or solution polymerization, bulk polymerization) polymerization, and add persulfate by weight percentage From 0.3% to 1.2%, at 40 to 55 ° C, and reacting for 40 to 60 hours, the acrylic resin II has a molecular weight greater than 150,000.

(2) Take the above-mentioned acrylic resin II, add 20% 4 μm diameter polyurethane microsphere elastomer (Zhejiang Donghua Industrial Co., Ltd.) in acrylic resin II by weight ratio, add 1 to 5% acrylic curing agent, stir evenly to obtain High filling, high toughness second insulation coating layer coating. See Table 1 for performance.

A3. Preparation of reflective shielding coatings;

(1) Take 11 parts of acrylic acid, 43 parts of acrylonitrile, 25 parts of butyl acrylate, 25 parts of hydroxyethyl acrylate, and polymerize the above raw materials through emulsion (or solution polymerization, bulk polymerization) to obtain acrylic resin III. Persulfate is 0.3% to 1.2%, reacted at 60 to 80 ° C for 10 to 20 hours, and the molecular weight of acrylic resin III is 50,000 to 70,000.

(2) Take 60 parts of the above-mentioned acrylic resin III, 20 parts of bisphenol A type epoxy resin, 7 parts of dicyandiamide, 7 parts of diamino diphenyl sulfone, and stir uniformly to obtain an acrylic reflection layer base resin;

(3) The metal filler is sheet-shaped silver-clad glass. Take sheet-shaped silver-clad glass (plate glass, S2015), the thickness direction is 1 to 2 microns, the plane size is 3 to 9 microns, and each piece of conductive powder has 3 to 5 branches. The activated shielding slurry is obtained after 24 hours of ultrasonic activation by an activator. The conductive powder activator is a silane coupling agent or a titanate coupling agent.

(4) Taking the acrylic reflective layer base resin and the activated shielding paste in a ratio of 1: 1 to obtain a coating of a reflective shielding coating.

A4. Purchase rolled copper foil in the market as the metal layer material (type Shandong Zhaoyuan Jinbao, electromagnetic shielding copper foil).

The second step, coating

A5. Remove oil and foreign matter on the inner surface of the carrier film roll;

A6. The prepared first insulating coating layer is coated on the inner surface of the carrier film roll with a thickness of 1 to 2 μm, and the first insulating coating layer is cured by oven drying; the oven temperature is 60 to 120 ° C, preferably 90 ° C; The speed is 5-30m / min, preferably 20m / min;

A7. The prepared second insulating coating layer is coated on the first insulating coating layer with a thickness of 2 to 7 μm, and the second insulating coating layer is cured by oven drying; the oven temperature is 60 to 120 ° C, preferably 90 ° C; Linear speed is 5-30m / min, preferably 20m / min;

A8. A metal layer is formed on the second insulating coating layer by a laminating machine and a rolled copper foil, and the film thickness is 3 to 9 μm, preferably 6 μm;

A9. Apply a prepared reflective shielding coating on the metal layer, with a thickness of 5-10 μm, and incorporate it into an oven to dry. The oven temperature is 60 to 120 ° C, preferably 90 ° C; the line speed is 5 to 30m / min, It is preferably 20m / min;

A10. Laminate a layer of protective film on the reflective shielding coating;

A11. Rewind.

The shielding effect of the double-layer electromagnetic shielding film in this embodiment is shown in Table 1.

Example 2

The manufacturing process of the double-layer electromagnetic shielding film in this embodiment is basically the same as that in Embodiment 1, except that the group of the first insulating coating layer coating in A1, the second insulating coating layer coating in A2, and the reflective shielding coating coating in A3 Points and ratio:

The proportion of each raw material of the acrylic resin I obtained in A1 is different. The addition amounts of acrylic acid, methyl acrylate, acrylonitrile, butyl acrylate, and isobornyl acrylate are 3, 10, 30, 10, and 5 parts, respectively. The amounts of pigment carbon black, titanium dioxide, and silica added to the acrylic resin I were 10%, 3%, and 5%, respectively.

The proportion of each raw material for the acrylic resin II obtained in A2 is different. The addition amounts of acrylic acid, ethyl acrylate, butyl methacrylate, and acrylonitrile are respectively 2, 10, 30, and 5 parts; The amount of the elastic microspheres was 10%, and the particle diameter was 7 μm.

The proportions of the raw materials for the acrylic resin III obtained in A3 are different. The addition amounts of acrylic acid, acrylonitrile, butyl acrylate, and hydroxyethyl acrylate are 7, 35, 20, and 20 parts, respectively. The ratio of raw materials is different. The bisphenol F-type epoxy resin replaces the bisphenol A-type epoxy resin. The addition amounts of acrylic resin III, bisphenol F-type epoxy resin, dicyandiamide, and diaminodiphenyl sulfone are 50 and 10, respectively. , 5, 5 servings.

Take flake silver-coated copper powder (Mitsui metal 1100YP, ball mill, use after 400 mesh sieving; or Fukuda Metal, 10% Agcoto Cu-HWQ 5μm, use directly), activate the ultrasonic shielding agent for 24 hours to obtain an activated shielding slurry .

The acrylic reflective layer base resin and the activated shielding paste are mixed in a ratio of 1: 5 to obtain a coating of a reflective shielding coating.

Example 3

The manufacturing process of the double-layer electromagnetic shielding film in this embodiment is basically the same as that in Embodiment 1, except that the group of the first insulating coating layer coating in A1, the second insulating coating layer coating in A2, and the reflective shielding coating coating in A3 Distribution ratio:

The proportion of each raw material for the acrylic resin I obtained in A1 is different. The addition amounts of acrylic acid, methyl acrylate, acrylonitrile, butyl acrylate, and isobornyl acrylate are 10, 30, 60, 30, and 10 parts, respectively. The amounts of pigment carbon black, titanium dioxide, and silica added to the acrylic resin I were 20%, 10%, and 15%, respectively.

The proportions of the raw materials for the acrylic resin II obtained in A2 are different. The addition amounts of acrylic acid, ethyl acrylate, butyl methacrylate, and acrylonitrile are 5, 40, 60, and 10 parts, respectively. The amount of the elastic microspheres was 30%, and the particle diameter was 1 μm.

The proportions of the raw materials for the acrylic resin III obtained in A3 are different. The addition amounts of acrylic acid, acrylonitrile, butyl acrylate, and hydroxyethyl acrylate are 15, 50, 30, and 30 parts, respectively. The proportion of raw materials is different. The phenolic epoxy resin replaces the bisphenol A type epoxy resin. The addition amounts of acrylic resin III, phenolic epoxy resin, dicyandiamide, and diaminodiphenyl sulfone are 70, 30, 10, and 10 parts, respectively.

Take a sheet-shaped silver-clad copper powder with a thickness of 1 to 2 μm and a plane size of 3 to 9 μm (Mitsui Metal 1100YP, ball mill, used after sieving at 400 mesh; or Fukuda Metal, 10% Agcoto Cu-HWQ 5 μm, used directly) The activator was ultrasonically activated for 24 hours to obtain an activated shielding slurry.

Take the acrylic reflective layer base resin and the activated shielding paste in a ratio of 1.5: 1 to mix uniformly to obtain a coating of a reflective shielding coating.

Example 4

This embodiment is basically the same as Example 1, except that the metal layer is made of rolled aluminum foil, and the first insulating coating layer, the second insulating coating layer, and the reflective shielding coating are prepared using polyurethane coating. The manufacturing process that can be used is as follows: .

B1. Prepare a first insulating coating layer;

(1) A polyester polyol (PEPA) and toluene diisocyanate (TDI) having a molecular weight of 1000 to 2000 are used to synthesize a hydroxyl-terminated polyurethane resin I at a functional group molar ratio of 1.2: 1, and a resin solid weight ratio of 0.5 to 1% organotin catalyst is added. The reaction is carried out at 40 to 60 ° C. for 8 to 10 hours, and then heated to 80 to 100 ° C. for 5 to 10 hours to synthesize a hydroxyl-terminated polyurethane resin I with a molecular weight of 1 to 30,000.

(2) Take the above polyurethane resin I, and add 15% pigment carbon black, 7% titanium dioxide, and 10% silicon oxide to the polyurethane resin I in a weight ratio, and then add 1 to 5% of the polyurethane curing agent, stir evenly to obtain abrasion resistance. Type first insulating coating layer coating. See Table 1 for performance parameters.

B2, preparing a second insulating coating layer;

(1) A polyester polyol (PEPA) and a hexamethylene diisocyanate (HDI) having a molecular weight of 3000 to 5000 are used to synthesize a hydroxyl-terminated polyurethane rubber II according to a functional group molar ratio of 1.1: 1. The resin solid weight ratio of 0.5 to 1% organotin catalyst is added, and the reaction is performed at 40 to 60 ° C for 8 to 10 hours, and then the temperature is raised to 80 to 100 ° C for 5 to 10 hours to synthesize a hydroxyl-terminated polyurethane resin II with a molecular weight of 3 to 60,000.

(2) Take the above-mentioned polyurethane rubber II, add 20% polyurethane microsphere elastomer with a diameter of 4 μm (Zhejiang Donghua Industrial Co., Ltd.) to the polyurethane rubber II by weight ratio, add a polyurethane curing agent, and stir uniformly to obtain a high filling, The performance parameters of the high toughness second insulating coating layer are shown in Table 1.

B3. Preparation of reflective shielding coating paint;

(1) Take a polyester polyol (PEPA) and toluene diisocyanate (TDI) with a molecular weight of 4000 to 6000 and prepolymerize it with a functional group molar ratio of 1.4: 1, and add an organotin catalyst with a resin solid weight ratio of 0.5 to 1%, 50 to The reaction was performed at 70 ° C. for 8 to 12 hours to obtain a hydroxyl-terminated prepolymer.

(2) Take 60 parts of the above-mentioned hydroxyl-terminated prepolymer, 5 parts of hexamethylene diisocyanate (HDI) trimer, 15 parts of bisphenol A type epoxy resin, and 15 parts of diaminodiphenyl sulfone, stir uniformly to prepare Obtain a polyurethane-type reflective layer matrix resin;

(3) The metal filler is flaky silver-clad copper powder. Take the flaky silver-clad copper powder (Mitsui Metal 1100YP, ball mill, and use after sieving at 400 mesh; or Fukuda Metal, 10% Agcoto Cu-HWQ 5 μm, directly use) , The thickness direction is 1 to 2 microns, the plane size is 3 to 9 microns, each leaf-like silver-clad copper powder has 3 to 5 branches, and the activated shielding slurry is obtained after ultrasonic activation for 24 hours.

(4) Take the above-mentioned polyurethane-type reflective layer base resin and the above-mentioned activated shielding paste and mix them uniformly in a ratio of 1: 1 to obtain a coating of a reflective-type shielding coating.

B4. Purchasing rolled aluminum foil as metal layer material in the market (type North China Aluminum, double zero foil.)

Example 5

The manufacturing process of the double-layer electromagnetic shielding film of this embodiment is basically the same as that of Embodiment 4, except that the group of the first insulating coating layer coating in B1, the second insulating coating layer coating in B2, and the reflective shielding coating coating in B3 Distribution ratio:

In B1, polyether polyol (PPG) replaces polyester polyol (PEPA), and diphenylmethane diisocyanate (MDI) replaces toluene diisocyanate (TDI). The molar ratio of the functional groups of the two is 1.1: 1, and a hydroxyl-terminated polyurethane is obtained. Resin; the amount of pigment carbon black, titanium dioxide, and silica added to the hydroxyl-terminated polyurethane resin I obtained above was 10%, 3%, and 5%, respectively.

The functional ratio of polyether polyol (PPG) instead of polyester polyol (PEPA) and hexamethylene diisocyanate (HDI) in B2 is 1.05: 1; the polyurethane resin II obtained above is added with polyurethane microsphere elastomer. The amount was 10%, and the particle size was 7 μm.

Diphenylmethane diisocyanate (MDI) in B3 replaces toluene diisocyanate (TDI), and the molar ratio of polyester polyol (PEPA) to its functional groups is 1.3: 1 to prepare a hydroxyl-terminated prepolymer; bisphenol F-type epoxy The resin replaces the bisphenol A type epoxy resin, and the added amounts of the hydroxyl-terminated prepolymer, hexamethylene diisocyanate (HDI) trimer, bisphenol F type epoxy resin, and diaminodiphenyl sulfone obtained above are 60, respectively. , 1, 10, 10 to obtain a polyurethane-type reflective layer matrix resin.

A leaf-shaped silver-clad copper powder having a thickness of 1 to 2 μm and a plane size of 3 to 9 μm was taken, and the activated shielding slurry was obtained after ultrasonic activation for 24 hours.

Take the above-mentioned polyurethane-type reflective layer base resin and the above-mentioned activated shielding paste and mix them in a ratio of 1: 5 to obtain a coating of a reflective-type shielding coating.

Example 6

The manufacturing process of the double-layer electromagnetic shielding film of this embodiment is basically the same as that of Embodiment 4, except that the group of the first insulating coating layer coating in B1, the second insulating coating layer coating in B2, and the reflective shielding coating coating in B3 Distribution ratio:

B1 in the terminal hydroxyl polycarbonate (PC) instead of polyester polyol (PEPA), benzene dimethylene diisocyanate (XDI) instead of toluene diisocyanate (TDI), the molar ratio of functional groups of the two is 1.3: 1, the end Hydroxyl polyurethane resin; the amount of pigment carbon black, titanium dioxide, and silica added to the obtained hydroxyl-terminated polyurethane resin I was 20%, 10%, and 15%, respectively.

B2 medium-term hydroxyl polycarbonate (PC) replaces polyester polyol (PEPA), isophorone diisocyanate (IPDI) replaces hexamethylene diisocyanate (HDI). The molar ratio of the functional groups of the two is 1.2: 1. Polyurethane resin was obtained; the amount of polyurethane microsphere elastomer (Zhejiang Donghua Industrial Co., Ltd.) added to the obtained polyurethane resin II was 30%, and the particle size was 1 μm.

In B3, xylylene diisocyanate (XDI) replaces toluene diisocyanate (TDI), and the molar ratio of polyester polyol (PEPA) to its functional groups is 1.5: 1 to prepare a hydroxyl-terminated prepolymer; phenolic epoxy resin replaces Bisphenol A epoxy resin, isophorone diisocyanate (IPDI) trimer instead of hexamethylene diisocyanate (HDI) trimer, hydroxyl-terminated prepolymer obtained above, phenolic epoxy resin, isophor Ketone diisocyanate (IPDI) and diaminodiphenyl sulfone were added in amounts of 80, 10, 20, and 20, respectively, to obtain a polyurethane-type reflective layer matrix resin.

A leaf-shaped silver-clad copper powder having a thickness of 1 to 2 μm and a plane size of 3 to 9 μm was taken, and activated with ultrasonic waves for 24 hours to obtain an activated shielding paste.

The above-mentioned polyurethane-type reflective layer base resin and the above-mentioned activated shielding paste are mixed uniformly in a ratio of 1.5: 5 to obtain a coating of a reflective-type shielding coating.

Example 7

The manufacturing process of the double-layer electromagnetic shielding film in this embodiment is basically the same as that in Embodiment 1, except that in the first configuration coating, the acrylic resin II in the second insulating coating layer coating is replaced with a carboxyl group having a molecular weight of 200,000 to 300,000. Nitrile rubber or hydroxy nitrile rubber; the metal layer is rolled silver foil. The acrylic-type reflective layer base resin in the reflective shielding coating is replaced by a rubber-type reflective layer base resin, 30 to 60 parts of carboxyl or hydroxybutyronitrile rubber, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic 30 to 50 parts of one or more epoxy resin multifunctional epoxy resins, 5 to 10 parts of dicyandiamide, and 10 to 20 parts of diaminodiphenyl sulfone, and uniformly stirred to obtain a rubber-type reflective layer matrix resin. Preferably, 45 parts of carboxyl or hydroxybutyronitrile rubber, 40 parts of one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy polyfunctional epoxy resin, dicyandiamide 7 parts and 15 parts of diaminodiphenyl sulfone.

Example 8

The manufacturing process of the double-layer electromagnetic shielding film of this embodiment is basically the same as that of Embodiment 1. The difference is that the electromagnetic wave shielding layer 5 is an absorption-type shielding coating 52. At the same time, the process in the coating in step 2 is slightly different. Wherein, the preparation of the absorption-type shielding coating B3 in step 1 is acrylic type, the steps are as follows:

(1) Take 7 parts of acrylic acid, 45 parts of acrylonitrile, 30 parts of hydroxyethyl acrylate, 15 parts of n-butyl methacrylate, add 0.3% to 1.2% persulfate by weight percentage, and react at 60 to 80 ° C for 10 -20 hours, the above raw materials are polymerized by emulsion (or solution polymerization, bulk polymerization) to obtain acrylic resin IV, and the molecular weight of acrylic resin IV is 50,000 to 70,000.

(2) Take 70 parts of the above-mentioned acrylic resin IV, 20 parts of bisphenol A-type epoxy resin, and 10 parts of diaminodiphenylsulfone, and stir uniformly to obtain an acrylic-type absorbent layer matrix resin.

(3) Take 30 parts of the above-mentioned acrylic-type absorption layer base resin, 20 parts of polypyrrole, and 50 parts of a mixture of acetylene carbon black and ferrite by weight, and mix to make an acrylic absorption-type shielding coating.

The second step, coating

B5. Remove oil and foreign matter on the inner surface of the carrier film roll;

B6. On the inside surface of the carrier film roll, apply the prepared first insulating coating layer 2 and second insulating coating layer 3 through a double-nozzle coating head at the same time, with thicknesses of 1 to 2 μm and 2 to 7 μm, respectively. One insulation coating layer 2 and the second insulation coating layer 3 are cured; the oven temperature is 60 to 120 ° C and the line speed is 5 to 30m / min; the oven temperature is 60 to 120 ° C, preferably 90 ° C; double-layer coating can improve Efficiency, product yield.

B7. The composite metal layer 4 is passed through a laminator on the second insulating layer;

B8. Apply the prepared absorption-type shielding coating 52 on the release film layer, with a thickness of 2-5 μm, and dry it in an oven. The oven temperature is 60-120 ° C, preferably 90 ° C; the line speed is 5-30m / min, preferably 20m / min;

B9. The metal layer 4 on the carrier film and the absorptive shielding coating layer 52 on the release film layer are subjected to thermocompression bonding;

B10. Rewinding.

Example 9

The manufacturing process of the double-layer electromagnetic shielding film in this embodiment is basically the same as that in Example 8. The difference is that the proportions of the raw materials for the acrylic resin IV obtained in A3 are different, acrylic acid, acrylonitrile, hydroxyethyl acrylate, and methacrylic acid. The amount of n-butyl ester added is 5, 30, 20, and 10 parts respectively; the raw material ratio of the acrylic-type absorption-type shielding coating resin is different. The bisphenol F epoxy resin replaces the bisphenol A epoxy resin. Resin IV, bisphenol F-type epoxy resin, and diaminodiphenylsulfone were added in amounts of 60, 10, and 5 parts, respectively.

Example 10

The manufacturing process of the double-layer electromagnetic shielding film in this embodiment is basically the same as that in Example 8. The difference is that the proportions of the raw materials for the acrylic resin IV obtained in A3 are different, acrylic acid, acrylonitrile, hydroxyethyl acrylate, and methacrylic acid. The amount of n-butyl ester added is 10, 60, 40, and 20 parts respectively. The raw material ratio of the acrylic-type absorption-type shielding coating resin is different. The phenolic epoxy resin replaces the bisphenol A-type epoxy resin. The acrylic resin IV, The added amounts of phenolic epoxy resin and diaminodiphenyl sulfone were 80, 30, and 15 parts, respectively.

Example 11

The manufacturing process of the double-layer electromagnetic shielding film in this embodiment is basically the same as that in Embodiment 4. The difference is that the electromagnetic wave shielding layer 5 is an absorption-type shielding coating 52. Among them, the preparation of the absorption-type shielding coating B3 is polyurethane-type. as follows:

(1) Take a polyester polyol with a molecular weight of 4000 to 6000, prepolymerize with toluene diisocyanate at a functional group molar ratio of 1.15: 1, add an organic tin catalyst, and react at 50 to 70 ° C for 8 to 12 hours to obtain a hydroxyl-terminated prepolymer. ;

(2) Take 70 parts of the above hydroxyl-terminated prepolymer, 5 parts of hexamethylene diisocyanate trimer, 15 parts of bisphenol A epoxy resin, 7 parts of diaminodiphenyl sulfone by weight, and stir to obtain Polyurethane-type absorbent base resin.

(3) Take 10 parts of the above-mentioned polyurethane-type absorption layer base resin, 10 parts of polyaniline, and 20 parts of a mixture of acetylene carbon black and silicon carbide by weight, and mix them to make an acrylic absorption-type shielding coating.

Example 12

The manufacturing process of the double-layer electromagnetic shielding film of this embodiment is basically the same as that of Example 11, except that the group distribution ratio of the absorption-type shielding coating is: Diphenylmethane diisocyanate (MDI) in B3 instead of toluene diisocyanate (TDI ), The molar ratio of polyester polyol (PEPA) and its functional groups is 1.1: 1 to prepare a hydroxyl-terminated prepolymer; a bisphenol F-type epoxy resin replaces a bisphenol A-type epoxy resin, and the obtained hydroxyl-terminated prepolymer The addition amounts of hexamethylene diisocyanate (HDI) trimer, bisphenol F-type epoxy resin, and diaminodiphenylsulfone were 60, 1, 10, and 5, respectively, to obtain a polyurethane-type reflective layer matrix resin. Polyaniline replaces polypyrrole, the aforementioned polyurethane-type reflective matrix resin.

Example 13

The manufacturing process of the double-layer electromagnetic shielding film in this embodiment is basically the same as that in Example 11, except that the group distribution ratio of the absorption-type shielding coating coating is: benzenedimethylene diisocyanate (XDI) in B3 instead of toluene diisocyanate ( TDI), the molar ratio of polyester polyol (PEPA) to its functional groups is 1.3: 1, and hydroxyl-terminated prepolymers are prepared; phenolic epoxy resin replaces bisphenol A type epoxy resin, isophorone diisocyanate (IPDI) The trimer replaces the hexamethylene diisocyanate (HDI) trimer. The added amounts of the hydroxyl-terminated prepolymer, isophorone diisocyanate (IPDI), phenolic epoxy resin, and diaminodiphenylsulfone obtained above are respectively 80, 10, 20, 10 to obtain polyurethane-type reflective layer matrix resin.

Example 14

The manufacturing process of the double-layer electromagnetic shielding film of this embodiment is basically the same as that of Example 7, except that the preparation of the absorption-type shielding coating paint of B3 is rubber-type, and the steps are as follows: Take the carboxyl or hydroxybutyronitrile rubber 30 by weight. ～ 60 parts, one or several of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy polyfunctional epoxy resin, 30-50 parts, and 5-10 parts of dicyandiamide, two 10-20 parts of amino diphenyl sulfone, stir well to prepare a rubber-type absorption layer matrix resin. Preferably, 45 parts of carboxyl or hydroxybutyronitrile rubber, 40 parts of one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy polyfunctional epoxy resin are taken by weight, 7 parts of dicyandiamide and 15 parts of diaminodiphenyl sulfone were made into a gel-type absorbent layer base resin; 50 parts of the rubber-type absorbent layer base resin, 30 parts of polythiophene, and 80 parts of a mixture of silicon carbide and ferrite were taken by weight. , Mixed to make a rubber-type absorption barrier coating paint.

Example 15

In this specific embodiment, the electromagnetic wave shielding layer 5 includes a reflection-type shielding coating 51 and an absorption-type shielding coating 52, and the reflection-type shielding coating 51 is provided between the metal layer and the absorption-type shielding coating 52. Among them, in the first step, the preparation steps of the reflection-type shielding coating 51 and the absorption-type shielding coating 52 are the same as those in the specific embodiments 1 and 8.

Example 16

In this specific embodiment, the electromagnetic wave shielding layer 5 includes a reflection-type shielding coating 51 and an absorption-type shielding coating 52, and the reflection-type shielding coating 51 is provided between the metal layer and the absorption-type shielding coating 52. Wherein, the preparation steps of the reflection-type shielding coating 51 and the absorption-type shielding coating 52 are the same as those in the specific embodiments 2 and 9.

Example 17

In this specific embodiment, the electromagnetic wave shielding layer 5 includes a reflection-type shielding coating 51 and an absorption-type shielding coating 52, and the reflection-type shielding coating 51 is provided between the metal layer and the absorption-type shielding coating 52. Wherein, the preparation steps of the reflection-type shielding coating 51 and the absorption-type shielding coating 52 are the same as those in the specific embodiments 3 and 10.

Example 18

In this specific embodiment, the electromagnetic wave shielding layer 5 includes a reflection-type shielding coating 51 and an absorption-type shielding coating 52, and the reflection-type shielding coating 51 is provided between the metal layer and the absorption-type shielding coating 52. The preparation steps of the reflective shielding coating 51 and the absorbing shielding coating 52 are the same as those in the specific embodiments 4 and 11.

Example 19

In this specific embodiment, the electromagnetic wave shielding layer 5 includes a reflection-type shielding coating 51 and an absorption-type shielding coating 52, and the reflection-type shielding coating 51 is provided between the metal layer and the absorption-type shielding coating 52. Wherein, the preparation steps of the reflection-type shielding coating 51 and the absorption-type shielding coating 52 are the same as those in the specific embodiments 5 and 12.

Example 20

In this specific embodiment, the electromagnetic wave shielding layer 5 includes a reflection-type shielding coating 51 and an absorption-type shielding coating 52, and the reflection-type shielding coating 51 is provided between the metal layer and the absorption-type shielding coating 52. Wherein, the preparation steps of the reflection-type shielding coating 51 and the absorption-type shielding coating 52 are the same as those in the specific embodiments 6 and 13.

Example 21

In this specific embodiment, the electromagnetic wave shielding layer 5 includes a reflection-type shielding coating 51 and an absorption-type shielding coating 52, and the reflection-type shielding coating 51 is provided between the metal layer and the absorption-type shielding coating 52. The steps for preparing the reflective shielding coating 51 and the absorptive shielding coating 52 are the same as those in the specific embodiments 7 and 14.

The performance of each layer of the double-layer electromagnetic shielding film in each embodiment of the present invention is shown in Table 1.

Table 1 Performance test results of each film layer

Claims (17)

1. A double-layer electromagnetic shielding film, comprising a carrier film (1), a first insulating coating layer (2) coated on the carrier film (1), and a first insulating coating layer (2). A second insulating coating layer (3), a metal layer (4) compounded on the second insulating coating layer (3), an electromagnetic wave shielding coating (5) coated on the metal layer (4), and provided on the electromagnetic wave shielding A release protective film (6) on the coating layer (5); the carrier film (1) is a matte release film; the coating of the first insulating coating layer (2) is an abrasion-resistant acrylate coating or Polyurethane coating with abrasion resistance greater than 1000 times and thickness of 1-2 μm; the coating of the second insulating coating layer (3) is a high-filling, high-toughness acrylate coating or polyurethane coating or rubber coating, and the number of times of bending resistance is greater than 80,000, with a thickness of 2 to 7 μm; the metal layer (4) is a thin film made of rolled metal foil with a thickness of 3 to 9 μm; the electromagnetic wave shielding coating (5) is a reflective shielding coating (51); The coating of the reflection-type shielding coating (51) includes a reflection-layer matrix resin and a metal filler, the reflection-layer matrix resin is an acrylic type, a polyurethane type, or a rubber type, and The metal filler is sheet-shaped silver-clad glass or sheet-shaped silver-coated copper powder or leaf-shaped silver-coated copper powder or dendritic silver-coated copper powder; the size of the metal filler in the thickness direction is 1 to 2 μm, and the plane size is 3 to 9 μm. The metal filler has 3 to 5 branches; the mass ratio of the reflective layer base resin of the reflective shielding coating (4) to the metal filler is 1: 1.5 to 1: 5.
2. A double-layer electromagnetic shielding film, comprising a carrier film (1), a first insulating coating layer (2) coated on the carrier film (1), and a first insulating coating layer (2). A second insulating coating layer (3), a metal layer (4) compounded on the second insulating coating layer (3), an electromagnetic wave shielding coating (5) coated on the metal layer (4), and provided on the electromagnetic wave shielding Release protective film (6) on the coating (5);

   The carrier film (1) is a matte release film; the coating of the first insulating coating layer (2) is an abrasion-resistant acrylate coating or a urethane coating, which has abrasion resistance greater than 1,000 times and a thickness of 1 to 2 μm The coating of the second insulating coating layer (3) is a high-filling, high-toughness acrylate coating or a polyurethane coating or a rubber coating, and the number of times of bending resistance is greater than 80,000, and the thickness is 2 to 7 μm; the metal layer (4) It is a thin film with a thickness of 3 to 9 μm made of rolled metal foil;

   The electromagnetic wave shielding coating (5) is an absorption-type shielding coating (52); the absorption-type shielding coating (52) includes 10 to 50 parts of an absorption layer base resin, polypyrrole, polyaniline, and polythiophene. 10 or 30 parts of acetylene black, silicon carbide, or ferrite, or 20 to 80 parts of ferrite are mixed, and the absorption layer matrix resin is acrylic type, polyurethane type, or rubber type.
3. A double-layer electromagnetic shielding film, comprising a carrier film (1), a first insulating coating layer (2) coated on the carrier film (1), and a first insulating coating layer (2). A second insulating coating layer (3), a metal layer (4) compounded on the second insulating coating layer (3), an electromagnetic wave shielding coating (5) coated on the metal layer (4), and provided on the electromagnetic wave shielding Release protective film (6) on the coating (5);

   The carrier film (1) is a matte release film; the coating of the first insulating coating layer (2) is an abrasion-resistant acrylate coating or a urethane coating, which has abrasion resistance greater than 1,000 times and a thickness of 1 to 2 μm The coating of the second insulating coating layer (3) is a high-filling, high-toughness acrylate coating or a polyurethane coating or a rubber coating, and the number of times of bending resistance is greater than 80,000, and the thickness is 2 to 7 μm; the metal layer (4) It is a thin film with a thickness of 3 to 9 μm made of rolled metal foil;

   The electromagnetic wave shielding coating (5) includes a reflective shielding coating (51) and the absorptive shielding coating (52) provided on the reflective shielding coating (51); the reflective shielding coating ( 51) The coating includes a reflective layer matrix resin and a metal filler, the reflective layer matrix resin is an acrylic type, a polyurethane type, or a rubber type, and the metal filler is a sheet-like silver-clad glass or a sheet-like silver-clad copper powder or a leaf-like silver Copper-clad powder or dendritic silver-clad copper powder; the size of the metal filler in the thickness direction is 1 to 2 μm, the plane size is 3 to 9 μm, the leaf-shaped metal filler has 3 to 5 branches; the reflective shield The mass ratio of the reflective layer matrix resin of the coating layer (4) to the metal filler is 1: 1.5 to 1: 5; the absorptive shielding coating layer (52) includes 10 to 50 parts of the absorbent layer matrix resin, polypyrrole, 10 to 30 parts of one or more of polyaniline and polythiophene, 20 or 80 parts of one or more of acetylene carbon black, silicon carbide, and ferrite, the absorbent layer base resin is acrylic Type or polyurethane type or rubber type.
4. The double-layer electromagnetic shielding film according to any one of claims 1-3, wherein the metal layer (4) is a rolled copper foil or a rolled aluminum foil or a rolled silver foil.
5. The double-layer electromagnetic shielding film according to claim 1 or 3, characterized in that the reflection-layer matrix resin of the reflection-type shielding coating (51) is an acrylic-type matrix resin, and the formula is as follows:

   (1) Take 7 to 15 parts of acrylic acid, 35 to 50 parts of acrylonitrile, 20 to 30 parts of butyl acrylate, and 20 to 30 parts of hydroxyethyl acrylate by weight, and react the above raw materials at 60 to 80 ° C for 10 to 20 hours. Acrylic resin III was obtained through polymerization; acrylic resin III was obtained with a molecular weight of 50,000 to 70,000;

   (2) Take 50 to 70 parts of the above-mentioned acrylic resin III by weight, one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy polyfunctional epoxy resin 10 to 30. Parts, 5 to 10 parts of dicyandiamide, and 5 to 10 parts of diaminodiphenyl sulfone, and uniformly stirred to obtain an acrylic reflective layer base resin.
6. The double-layer electromagnetic shielding film according to claim 1 or 3, characterized in that the reflection-layer matrix resin of the reflection-type shielding coating (51) is a polyurethane-type matrix resin, and the formula is as follows:

   (1) Take a polyester polyol with a molecular weight of 4000 to 6000, and one or more of toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, and the molar ratio of functional groups is 1.3 to 1.5: 1. , Prepolymerization, prepolymerization, adding an organotin catalyst, and reacting at 50 to 70 ° C for 8 to 12 hours to obtain a hydroxyl-terminated prepolymer;

   (2) Take 60 to 80 parts of the above-mentioned hydroxyl-terminated prepolymer, 1 to 10 parts of hexamethylene diisocyanate trimer or isophorone diisocyanate trimer by weight, bisphenol A epoxy resin, bis 10 to 20 parts of one or more of a phenol F type epoxy resin and a phenolic epoxy polyfunctional epoxy resin, and 10 to 20 parts of diaminodiphenyl sulfone, uniformly stirred to obtain a polyurethane-type reflective layer matrix resin.
7. The double-layer electromagnetic shielding film according to claim 1 or 3, characterized in that the reflection-layer matrix resin of the reflection-type shielding coating (51) is a rubber-type reflection-layer matrix resin, and the formula is as follows:

   30 to 60 parts of carboxyl or hydroxybutyronitrile rubber, 30 to 50 parts of one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy polyfunctional epoxy resin by weight 5-10 parts of dicyandiamide and 10-20 parts of diaminodiphenyl sulfone, stir well to prepare a rubber-type reflective layer matrix resin.
8. The double-layer electromagnetic shielding film according to claim 2 or 3, characterized in that the absorption layer base resin of the absorption-type shielding coating (52) is an acrylic resin, and the formula is as follows:

   (1) Take 5 to 10 parts of acrylic acid, 30 to 60 parts of acrylonitrile, 20 to 40 parts of hydroxyethyl acrylate, and 10 to 20 parts of n-butyl methacrylate. Add persulfate initiator based on the weight percentage of the reactant. 60 ~ 80 ℃, reaction for 10 ~ 20h, acrylic resin IV was prepared by emulsion polymerization of the above raw materials;

   (2) Take 60 to 80 parts of the above-mentioned acrylic resin IV by weight, one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy polyfunctional epoxy resin, or 10 to 30 Parts, 5 to 10 parts of diaminodiphenyl sulfone, and uniformly stirred to obtain an acrylic absorbent layer base resin.
9. The double-layer electromagnetic shielding film according to claim 2 or 3, characterized in that the absorption layer base resin of the absorption-type shielding coating (52) is a polyurethane-type resin, and the formula is as follows:

   (1) Take a polyester polyol with a molecular weight of 4000 to 6000, and one or more of toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, and the functional group molar ratio of 1.1 to 1.2: 1 , Prepolymerization, adding an organotin catalyst, and reacting at 50 to 70 ° C for 8 to 12 hours to obtain a hydroxyl-terminated prepolymer;

   (2) Take 60 to 80 parts of the above-mentioned hydroxyl-terminated prepolymer, 1 to 10 parts of hexamethylene diisocyanate trimer or isophorone diisocyanate trimer by weight, bisphenol A epoxy resin, bis 10 to 20 parts of one or more of a phenol F type epoxy resin and a phenolic epoxy multifunctional epoxy resin, and 5 to 10 parts of diaminodiphenyl sulfone, and uniformly stirred to obtain a polyurethane-type absorption layer matrix resin.
10. The double-layer electromagnetic shielding film according to claim 2 or 3, characterized in that: the base resin of the absorption layer of the absorption-type shielding coating (52) is a rubber-type resin, and the formula is as follows:

    30 to 60 parts of carboxyl or hydroxybutyronitrile rubber, 30 to 50 parts of one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolic epoxy polyfunctional epoxy resin by weight 5-10 parts of dicyandiamide and 10-20 parts of diaminodiphenyl sulfone, stir well to prepare a rubber-type absorption layer matrix resin.
11. The double-layer electromagnetic shielding film according to any one of claims 1 to 3, wherein the coating of the first insulating coating layer (2) is an acrylate coating, and the formula is as follows:

    (1) Take 3 to 10 parts of acrylic acid, 10 to 30 parts of methyl acrylate, 30 to 60 parts of acrylonitrile, 10 to 30 parts of butyl acrylate, and 5 to 10 parts of isobornyl acrylate by weight. Reaction for 30-60 hours. Acrylic resin I is prepared through emulsion or solution or bulk polymerization.

    (2) Take the above acrylic resin I, and add 10% to 20% pigment carbon black, 3 to 10% titanium dioxide, 5 to 15% silicon oxide, and 1 to 5% acrylic curing agent to the acrylic resin I in a weight ratio. Stir evenly to produce a wear-resistant coating for the first insulation coating layer, with abrasion resistance exceeding 1,000 times.
12. The double-layer electromagnetic shielding film according to any one of claims 1-3, wherein the coating of the first insulating coating layer (2) is a polyurethane coating, and the formula is as follows:

    (1) Take one or more of polyester polyols, polyether polyols, and hydroxyl-terminated polycarbonates with a molecular weight of 1000 to 2000, and toluene diisocyanate, diphenylmethane diisocyanate, xylylene diamine One or more of isocyanates are added at a functional group molar ratio of 1.1 to 1.3: 1, an organic tin catalyst is added, and the reaction is carried out at 40 to 60 ° C for 8 to 10 hours, and then heated to 80 to 100 ° C for 5 to 10 hours to synthesize a hydroxyl-terminated polyurethane. Resin I has a molecular weight of 10,000 to 30,000;

    (2) Take the above polyurethane resin I, and add 10% to 20% pigment carbon black, 3 to 10% titanium dioxide, 5 to 15% silicon oxide, and 1 to 5% polyurethane curing agent to the polyurethane resin I in a weight ratio, and stir Uniform, the first insulation coating layer of abrasion-resistant coating is produced, and the abrasion resistance meets more than 1,000 times.
13. The double-layer electromagnetic shielding film according to any one of claims 1 to 3, wherein the coating of the second insulating coating layer (3) is an acrylate coating, and the formula is as follows:

    (1) Take 2 to 5 parts of acrylic acid, 10 to 40 parts of ethyl acrylate, 30 to 60 parts of butyl methacrylate, and 5 to 10 parts of acrylonitrile by weight, and react at 40 to 55 ° C for 40 to 60 hours. Acrylic resin II is prepared by solution or bulk polymerization, and the molecular weight of acrylic resin II is greater than 150,000;

    (2) Take the above-mentioned acrylic resin II, and add 10-30% organic elastic microspheres with a diameter of 1-7 μm to the acrylic resin II in a weight ratio to make a second high filling property, high toughness and good bending resistance. Acrylic paint for insulation coating layer; resistance to bending is greater than 80,000.
14. The double-layer electromagnetic shielding film according to any one of claims 1-3, wherein the coating of the second insulating coating layer (3) is a polyurethane coating, and the preparation process is as follows:

    (1) Take one or more of polyester polyol, polyether polyol, and hydroxyl-terminated polycarbonate with a molecular weight of 3000 to 5000, and one of hexamethylene diisocyanate and isophorone diisocyanate Or several kinds of functional groups with a molar ratio of 1.05 to 1.2: 1, adding an organotin catalyst, reacting at 40 to 60 ° C for 8 to 10 hours, and then heating to 80 to 100 ° C for 5 to 10 hours to synthesize a hydroxyl-terminated polyurethane resin II. ~ 60,000;

    (2) Take the above-mentioned polyurethane rubber II, and add 10-30% organic elastic microspheres with a diameter of 1-7 μm to the polyurethane resin II according to its weight ratio, and stir evenly to obtain high filling, high toughness, and bending resistance. Good performance of the second insulating coating layer coating, the number of times of bending resistance is greater than 80,000.
15. The double-layer electromagnetic shielding film according to any one of claims 1 to 3, wherein the coating of the second insulating coating layer (3) is a rubber coating, and the formula is as follows:

    Take carboxyl nitrile rubber or hydroxybutyronitrile rubber with a molecular weight of 200,000 to 300,000, and add 10 to 30% of organic elastic microspheres with a diameter of 1 to 7 μm to the rubber coating by weight ratio to obtain high filling, high toughness, and resistance Good bendability The second insulation coating layer coating has a bending resistance greater than 80,000.
16. The method for preparing a double-layer electromagnetic shielding film according to any one of claims 1-3, comprising the following steps: first step, A1, preparing a coating of a first insulating coating layer (2); A2, the coating of the second insulating coating layer (3); A3, the metal layer (4) made of rolled metal foil; A4, the coating of the electromagnetic wave shielding layer (5);

    The second step, coating

    A5. Remove the oil and foreign matter on the inner surface of the carrier film (1) roll;

    A6. The prepared first insulating coating layer (2) is coated on the inner surface of the carrier film (1) with a thickness of 1 to 2 μm, and the first insulating coating layer is cured by oven drying; the oven temperature is 60 to 120 ° C; Linear speed is 5 ～ 30m / min;

    A7. Coat the prepared second insulating coating layer (3) on the first insulating coating layer (2) with a thickness of 2 to 7 μm. The second insulating coating layer is cured by oven drying; the oven temperature is 60 to 120 ° C. ; Linear speed is 5 ～ 30m / min;

    A8. A metal layer (4) is laminated on the second insulating coating layer (3) through a laminator;

    A9. The prepared electromagnetic wave shielding layer (5) is coated on the metal layer (4) with a thickness of 2 to 5 μm, and is then dried in an oven at an oven temperature of 60 to 120 ° C; and a line speed of 5 to 30 m / min ;

    A10. Thermally attach a release protective film layer (6) on the electromagnetic wave shielding layer (5);

    A11. Rewind.
17. The method for preparing a double-layer electromagnetic shielding film according to any one of claims 1-3, comprising the following steps:

    The first step, the first step, B1, preparing the coating of the first insulating coating layer (2); B2, coating of the second insulating coating layer (3); B3, the metal layer (4) made of rolled metal foil; Coatings for electromagnetic wave shielding layer (5);

    The second step,

    B5. Remove oil and foreign matter on the inner surface of the carrier film (1) roll;

    B6. On the inside of the carrier film roll, apply the above-mentioned prepared first insulating coating layer (2) and second insulating coating layer (3) at the same time through a double-nozzle coating head. Drying to cure the first insulating coating layer (2) and the second insulating coating layer (3); the oven temperature is 60 to 120 ° C, and the line speed is 5 to 30 m / min;

    B7. The metal layer (4) is laminated on the second insulating coating layer (3) through a laminator;

    B8. Coat the prepared electromagnetic wave shielding layer (5) on the release protective film layer (6), and put it into the oven to dry. The oven temperature is 60 ～ 120 ℃; the line speed is 5 ～ 30m / min;

    B9. The metal layer (4) on the carrier film and the electromagnetic wave shielding layer (5) on the release protective film layer (5) are hot-pressed and compounded;

    B10. Rewinding.

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