WO2019214635A1 - Magnetic shielding material, and preparation method therefor and application thereof - Google Patents

Abstract

A magnetic shielding material, and a preparation method therefor and an application thereof. A magnetic shielding material, comprising a magnetic layer (200), and a protective film (10) and a release film (40) provided at both sides of the magnetic layer (200), separately. The magnetic layer (200) comprises at least one magnetic material sheet layer (30) comprising several magnetic material fragments (31), gaps (32) among the magnetic material fragments (31) are at least filled with air. A first adhesive layer (21) is provided between the protective film (10) and the magnetic layer (200). A second adhesive layer (22) is provided between the release film (40) and the magnetic layer (200). The preparation method solves the problem of the prior art of the complex preparation process of a magnetic shielding material, and the prepared magnetic shielding material has good property.

Description

Magnetic isolation material and preparation method and application thereof Technical field

The invention relates to the field of magnetic isolation materials, in particular to a magnetic isolation material, a preparation method of the magnetic isolation material, a magnetic isolation material obtained by the preparation method and the application of the magnetic isolation material.

Background technique

Wireless charging is a technology for charging the battery of a terminal electrical device in a wireless manner, and the power supply end and the power receiving end do not need to be physically connected. At present, there are four main ways to achieve wireless power transmission: electromagnetic induction, magnetic resonance, electric field coupling, and radio waves. The mainstream wireless charging devices on the market are mainly electromagnetic induction.

Wireless charging converts electrical energy into magnetic field energy through the transmitting end coil, and the receiving end coil receives the magnetic field energy and converts it into electric energy to charge the device. The principle of near field communication and wireless charging is the same, but near field communication is applied to the transmission of electronic information. The wireless charging receiver module has two types of external and built-in. If it is built into a terminal device such as a mobile phone, many technical problems need to be solved. The performance and volume of the magnetic isolation material determine whether the material is suitable for use in a terminal device such as a mobile phone. When a terminal device such as a mobile phone performs wireless charging, an alternating magnetic field is generated, which requires that a magnetic isolation material is used in the wireless charging module to provide a low-impedance path for the magnetic field, and the loss of the material itself cannot be excessively high, thereby avoiding consumption of magnetic field energy. In order to prevent the wireless charging magnetic field from interfering with the normal operation of other components of the device, the shielding effect of the magnetic shielding material and the heat conduction or heat dissipation effect are required to be good. In addition, the thinning trend of the electronic product determines that the magnetic isolation material in the wireless charging module must be done very well. Thin, these put high demands on the magnetic isolation material in the wireless charging module. The same, near-field communication work will also face these problems.

In order to solve the problems of heat generation during charging, low charging efficiency, difficulty in thinning, and the like, the prior art utilizes an ultra-thin magnetic alloy material such as an amorphous or nanocrystalline strip having high magnetic permeability. The thickness of the single-layer magnetic alloy material ranges from 15μm to 40μm, which can be superimposed to improve the overall inductance of the material, and the structure design is more flexible and convenient. Amorphous magnetic alloy materials have much higher magnetic permeability and saturation magnetic induction than traditional ferrite materials, which means that amorphous alloy materials can be made very thin, providing a high-efficiency and low-impedance working path for the charging magnetic field, and because of the material. The magnetic component content is high, and the shielding effect is good, which greatly avoids the interference of the magnetic field penetrating magnetic shielding material on the internal components of the electronic product, and can also effectively shield the internal magnetic field of the electronic product from interfering with the charging coil.

The magnetic permeability and saturation flux density of amorphous magnetic alloy materials are ideal for use in wireless charging modules. However, when charging wirelessly, it is an alternating magnetic field. When magnetically dissociating materials work in an alternating magnetic field, they will generate magnetic fields due to the material itself. Loss, this part of the loss includes hysteresis loss, eddy current loss and other losses. The eddy current loss is an important part of the loss under the condition of wireless charging frequency. Since the amorphous magnetic alloy material is a metal material, the resistivity is relatively low, if not the material For further processing, it will produce more serious eddy current loss on the amorphous magnetic alloy material, consume the working magnetic field, and thus reduce the charging efficiency of the wireless charging; in addition, when the wireless charging is performed, the area of the alloy magnetic isolation material unit The larger, the easier it is to create eddy current effects on a large area. Therefore, the alloy magnetic isolation material needs to be fragmented, and the large-area alloy magnetic isolation material is divided into small fragments, and the fragment unit and the fragment unit are insulated from each other. Greatly reduce the eddy current effect.

CN104011814A discloses a magnetic field shielding sheet for a wireless charger, comprising: at least one layer of a thin magnetic sheet formed of an amorphous strip separated into a plurality of fine pieces, and a protective film adhered through the first adhesive layer And a double-sided tape bonded to the other surface of the thin-plate magnetic sheet by a second adhesive layer disposed on one side; a gap between the plurality of fine sheets is formed by the first adhesive A portion of the junction layer and the second bonding layer are filled to insulate the plurality of fine sheets from each other. The disclosed technical solution uses a glue layer to fill the air gap, because the glue layer is sticky, and the air gap is filled, because the viscosity of the glue layer causes stress between the magnetic material fragments, and the glue has a certain pressing force after being solidified. Stress and squeezing force will cause deformation of the debris, which will lead to the change of the orientation of the debris unit, and lead to the increase of the gap between the debris units. The orientation of the fragment unit will lead to a decrease in the magnetic permeability of the material, an increase in the magnetic resistance, and more magnetic energy. It is consumed, which leads to a decrease in the ability of the material to conduct a magnetic field. In addition, the manufacturing method of CN104011814A uses two pressurizing units to perform two presses in order to allow the adhesive layer to enter the gap, and the efficiency is low, and the manufacturing process is complicated.

In summary, the preparation process of the magnetic isolation material in the prior art is complicated, and the performance of the magnetic isolation material is not good.

Summary of the invention

The object of the present invention is to overcome the problems of the complicated preparation process of the magnetic isolation material and the poor performance of the magnetic isolation material existing in the prior art, and to provide a magnetic isolation material, a preparation method thereof and an application thereof.

In order to achieve the above object, a first aspect of the present invention provides a magnetic shielding material comprising: a magnetic layer; and a protective film and a release film disposed on different sides of the magnetic layer, wherein the magnetic layer Having at least one magnetic material sheet layer, the magnetic material sheet layer containing a plurality of magnetic material fragments, and a gap between the magnetic material pieces is at least partially filled with air; a first glue is disposed between the protective film and the magnetic layer a second adhesive layer is disposed between the release film and the magnetic layer.

Preferably, the magnetically permeable material further comprises a first coating disposed between the magnetic layer and the first adhesive layer, and/or a first layer disposed between the magnetic layer and the second adhesive layer a second coating; wherein the first coating and/or the second coating are each independently selected from at least one of a heat conductive or heat dissipating coating, a metal barrier coating, and an ink coating.

A second aspect of the invention provides a method for preparing a magnetic isolation material, wherein the preparation method comprises the following steps:

(1) subjecting at least one sheet of magnetic material to heat treatment under a reducing atmosphere or an inert atmosphere;

(2) one side of the heat-treated magnetic material sheet is coated with the first coating layer, and the other uncoated surface is the exposed surface;

(3) attaching a protective film to the first coating layer by a double-sided tape, and attaching the release film to the exposed surface by a double-sided tape to obtain a magnetic material component;

(4) fracturing the magnetic material component such that the magnetic material sheet in the magnetic material component is split into a plurality of magnetic material fragments; the first coating such that a gap between the magnetic material fragments is at least partially Air filled.

A third aspect of the invention provides a method for preparing a magnetic isolation material, wherein the preparation method comprises the following steps:

(1) subjecting at least one sheet of magnetic material to heat treatment under a reducing or inert atmosphere;

(2) one side of the heat-treated magnetic material sheet is coated with a second coating layer, and the other uncoated surface is a bare surface;

(3) attaching a release film to the second coating layer by a double-sided tape, and bonding a protective film to the exposed surface through a double-sided tape to obtain a magnetic material component;

(4) fracturing the magnetic material component such that the magnetic material sheet in the magnetic material component is split into a plurality of magnetic material fragments; the second coating is such that a gap between the magnetic material fragments is at least partially Air filled.

A fourth aspect of the invention provides a method for preparing a magnetic isolation material, wherein the preparation method comprises the following steps:

(1) subjecting at least one sheet of magnetic material to heat treatment under a reducing or inert atmosphere;

(2) coating the first coating layer and the second coating layer on both sides of the heat-treated magnetic material sheet;

(3) attaching a protective film to the first coating layer by a double-sided tape, and bonding the release film to the second coating layer by a double-sided tape to obtain a magnetic material component;

(4) fracturing the magnetic material component such that the magnetic material sheet in the magnetic material component is split into a plurality of magnetic material fragments; the first coating and the second coating are such that between the magnetic material fragments The void is at least partially filled with air.

A fifth aspect of the present invention provides a magnetic spacer material prepared by the production method of the present invention.

The sixth aspect of the invention provides the application of the magnetic isolation material of the invention in a wireless charging module or a near field communication module.

The invention reduces the eddy current loss in the working process by fracturing the magnetic sheet into small units (magnetic material fragments) by the fracturing treatment of the magnetic shielding material, and the inventors of the present invention found that between the magnetic material fragments The void-filled material, which is at least partially filled with air, is filled with glue compared to the gap between the prior art pieces of magnetic material, and has better magnetic properties. Preferably, the double-sided coating (the first coating and/or the second coating) which does not flow under high temperature and mechanical action can be added to one side or both sides of the magnetic layer of the magnetic shielding material, thereby effectively preventing the double-sided The glue enters the air gap between the pieces of the magnetic flakes to ensure that the air gap is not filled, and the air gap is used to reduce the eddy current effect during use. In addition, the coating used may have heat conduction or the like according to the above functions. Features such as heat dissipation and conductivity help to enhance the shielding performance or thermal or thermal performance of the material. Moreover, the invention can perform overall fracturing treatment on a plurality of magnetic material sheets, thereby ensuring the appearance flatness of the material, thereby ensuring the performance of the material, and greatly improving the efficiency of fracturing.

DRAWINGS

Figure 1 is a schematic cross-sectional view of a magnetic material assembly prior to fracturing of the present invention;

Figure 2 is a schematic cross-sectional view of a magnetic shielding material of the present invention;

Figure 3 is a plan view showing a magnetic material sheet layer of the magnetic shielding material of the present invention;

Figure 4 is a schematic illustration of the fracturing process of the present invention.

Description of the reference numerals

10-protective film 20-double-sided adhesive layer

21-first adhesive layer 22-second adhesive layer

30-magnetic material sheet layer 31-magnetic material fragments

32-air gap 40-release film

51-first coating 52-second coating

60-Fracture machine upper roll 61-protrusion

62-Fractureer's lower roll 200-magnetic layer

detailed description

The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to include values that are close to the ranges or values. For numerical ranges, the endpoint values of the various ranges, the endpoint values of the various ranges and the individual point values, and the individual point values can be combined with one another to yield one or more new ranges of values. The scope should be considered as specifically disclosed herein.

A first aspect of the present invention provides a magnetic isolation material. As shown in FIG. 2 and FIG. 3, the magnetic isolation material includes: a magnetic layer 200, and a protective film 10 and a release film 40 disposed on different sides of the magnetic layer. Wherein the magnetic layer contains at least one magnetic material sheet layer 30, the magnetic material sheet layer containing a plurality of magnetic material fragments 31, and a gap (air gap 32) between the magnetic material fragments is at least partially filled with air; A first adhesive layer 21 is disposed between the protective film and the magnetic layer, and a second adhesive layer 22 is disposed between the release film and the magnetic layer.

In the present invention, the gap between the magnetic material fragments is at least partially filled with air, or the gap between the magnetic material fragments may be completely filled with air. In this case, the magnetic layer does not contain double-sided tape; or may be magnetic The gap between the material fragments is partially filled with air and partially filled with double-sided tape. In this case, the magnetic layer contains double-sided tape. The inventors of the present invention found during the research that when there is an air gap between the pieces of magnetic material, there is no air gap (filled by double-sided tape) between the pieces of magnetic material as compared with the prior art. Magnetic properties, and help to improve the quality factor of the magnetic isolation material, reducing the magnetic reluctance of the material.

According to the present invention, the air gap between the pieces of magnetic material can be observed by slicing and performing metallographic analysis to indicate that the gap between the pieces of magnetic material is at least partially filled with air. The specific steps of the metallographic analysis include: 1. Sampling, slicing the magnetic isolation material to expose the cross section; 2. Sealing, filling the through hole with a suitable resin glue and sealing the plate. The purpose of the sealing is to Clamping the sample to reduce deformation; 3, grinding the sheet, using the cutting force of the sandpaper on the high-speed turntable to smooth the cut; 4, polishing, in order to eliminate the scratches of the sandpaper, to see the truth of the slice, must be carefully and meticulously carried out Polished for observation; 5. Analysis, observation and analysis with a metallographic microscope or scanning electron microscope.

According to the invention, preferably, in the magnetic layer, the number of the magnetic material sheet layers is 1-10 layers. For example, the number of magnetic material sheet layers is 1 layer, 2 layers, 4 layers, 5 layers, 6 layers, 8 layers, 10 layers, etc., preferably 2-6 layers.

According to a preferred embodiment of the invention, a double-sided adhesive layer 20 is disposed between adjacent layers of said magnetic material. Specifically, the magnetic layer is composed of an alternating structure formed of a magnetic material sheet layer and a double-sided adhesive layer, and an outermost layer of the magnetic layer is a magnetic material sheet layer. The present invention preferably uses a lamination to form a magnetically permeable material for the purpose of increasing the electrical resistivity of the single-layer magnetic flake layer and reducing the magnetic reluctance of the single-layer magnetic flake layer. This preferred embodiment satisfies the need for the normal magnetic field of the electronic product. At the same time, the eddy current loss of the magnetic isolation material as a whole is greatly reduced.

In the present invention, the magnetic material is preferably an amorphous or nanocrystalline magnetic alloy material. In the circuit, the current conduction causes the wire to flow completely, and there is no leakage outside the wire, and the magnetic field of the magnetic material cannot be completely confined to a given path. However, if the magnetic permeability of the magnetic material (positively related to the inductance) is much higher than the magnetic permeability of the substance surrounding it, the majority of the magnetic field will be concentrated in the magnetic material, and the magnetic field leaking to the surrounding material is almost negligible. The higher the magnetic permeability of the magnetic material, the lower its magnetic reluctance, and the higher the magnetic flux in the high permeability material than the magnetic flux in the low permeability material. Therefore, the magnetic isolation material of the present invention preferably selects an amorphous and nanocrystalline alloy material which is more capable of providing high magnetic permeability when selecting a magnetic material sheet layer, and the material has a higher saturation magnetic induction intensity and can accommodate more magnetic fields. It is not easy to reach saturation. Further preferably, the magnetic material is an Fe-based, Co-based or Ni-based amorphous or nanocrystalline magnetic alloy material. The preferred magnetic material has a much higher magnetic permeability and saturation magnetic induction than the conventional ferrite material, which means that the magnetic material can be made thin, and the magnetic component of the material is high and the shielding effect is good. Further preferably, the magnetic material is an Fe-based amorphous or nanocrystalline magnetic alloy material.

According to a preferred embodiment of the invention, the magnetic material sheet layer has a thickness of from 10 to 35 μm. For example, the thickness of the magnetic material sheet layer is 10 μm, 15 μm, 20 μm, 23 μm, 25 μm, 27 μm, 30 μm, and 35 μm. More preferably, the thickness of the amorphous magnetic alloy material is 15 μm to 30 μm, for example, the thickness of the amorphous magnetic alloy material is 15 μm, 20 μm, 23 μm, 25 μm, 27 μm, 30 μm; the thickness of the nanocrystalline magnetic alloy material is 15 μm to 25 μm, for example The thickness of the amorphous magnetic alloy material is 15 μm, 20 μm, 23 μm, and 25 μm.

According to a preferred embodiment of the invention, the magnetic material foil layer has a width of from 10 to 213 mm, preferably from 30 to 100 mm. For example, the width of the magnetic material sheet layer is 20 mm, 50 mm, 60 mm, 142 mm, 170 mm, and 200 mm.

According to a preferred embodiment of the present invention, the magnetically permeable material further comprises a first coating layer 51 between the magnetic layer and the protective film, and/or a second coating layer 52 between the magnetic layer and the release film, Wherein the first coating and/or the second coating are each independently selected from at least one of a heat conducting or heat dissipating coating, a metal shielding coating and an ink coating.

It should be noted that the “first” and “second” in the present invention are only for distinguishing coatings and adhesive layers at different positions, and do not form any limiting effect on the specific performance parameters of the coating and the rubber layer.

The magnetic isolation material provided by the present invention may preferably contain the first coating layer or the second coating layer, or may include the first coating layer and the second coating layer, and further preferably contain the first coating layer. Coating and second coating.

According to the invention, the first coating layer and the second coating layer do not flow under high temperature and mechanical action, and can effectively prevent the double-sided adhesive from entering the air gap between the magnetic material fragments, ensuring that the air gap is not filled by the double-sided adhesive. The air gap is used to reduce the eddy current effect during use to ensure the magnetic properties of the material. Avoiding the filling of the air gap on the one hand can prevent the pressing force of the rubber layer from causing a change in the orientation of the debris, and is more advantageous for reducing the ability of the magnetic insulating material to conduct and accommodate the magnetic field; the present invention tries to avoid another filling of the air gap by the adhesive layer. The purpose is to prevent the pressing force of the rubber layer from causing the spacing between the fragments to become larger, increasing the edge effect, causing the magnetic field to diffuse at the fracture of the magnetic sheet layer, and reducing the ability of the magnetic isolation material to conduct and accommodate the magnetic field. In the working environment, the closed path of the magnetic field is split by the air gap, so that the magnetic circuit becomes a series of high magnetic permeability magnetic material and air gap. Because it is a series circuit, the high magnetic permeability The magnetic flux in the magnetic material should be equal to the magnetic flux in the air gap. At this time, the magnetic flux diffusion in the air gap is unavoidable. It is called the edge effect. If the length of the air gap is small relative to other sizes, most of the magnetic flux is Will be concentrated on both sides of the magnetic material at the air gap, the edge effect can be ignored.

Preferably, the first coating and/or the second coating are each independently selected from at least one of a heat conducting or heat dissipating coating, a metal barrier coating and an ink coating, further preferably a heat conducting or heat dissipating coating. . This preferred functional coating helps to enhance the thermal or thermal properties or shielding properties of the material. The amorphous and nanocrystalline alloy materials are metal materials, and the magnetic isolation materials made of the materials have low resistivity. Although the magnetic isolation materials have high magnetic permeability, they are inevitably generated when working in an alternating magnetic field. Larger eddy current loss, and further because the magnetic material itself consumes magnetic field energy, which reduces the charging efficiency and causes the electronic product to generate heat. This is what we do not want to see. In the preferred solution of the present invention, the sheet is shaped by shredding. The magnetic sheet layer is split into a plurality of fragmented fine units, and the air gap is used to block the current to prevent the generation of large-area eddy currents. It is preferable to prevent the heat generation of the electronic product from being serious by adding a heat conduction or heat dissipation coating.

The heat conducting or heat dissipating coating in the present invention refers to a coating having a heat conducting and/or heat dissipating function.

According to the invention, preferably, the thickness of the first coating layer and/or the second coating layer is each independently from 1 to 20 μm, further preferably from 3 to 8 μm. For example, it may be 1 μm, 3 μm, 5 μm, 8 μm, and 10 μm.

The composition and thickness of the first coating layer and the second coating layer in the present invention may be the same or different, and the present invention is not particularly limited thereto.

According to a preferred embodiment of the invention, the heat conducting or heat dissipating coating has a heat conduction or heat dissipation coefficient of 10 to 200 W/(m·k), more preferably 10 to 50 W/(m·k).

Preferably, the heat conducting or heat dissipating coating layer comprises a nano carbon material and a binder, preferably the carbon nano material is at least one selected from the group consisting of carbon black, graphene and ceramic powder, preferably carbon black; The binder is selected from the group consisting of a resin and/or acrylic acid, preferably a resin, and more preferably an epoxy resin. The heat conducting or heat dissipating coating can quickly conduct and radiate heat generated during the working process, thereby improving the final performance of the magnetic insulating material and reducing the temperature rise of the electronic product.

According to a preferred embodiment of the present invention, the content of the nano-carbon material is 30-70% by weight based on the total weight of the heat-conductive or heat-dissipating coating, and the content of the binder is 30-70 weight. %.

According to a preferred embodiment of the invention, the metal barrier coating is selected from at least one of a silver coating, a copper coating and an aluminum coating.

According to a preferred embodiment of the present invention, the ink coating layer contains a pigment and a binder, and preferably, the pigment is at least one selected from the group consisting of carbon black, titanium white, zinc antimony white, and organic pigment, preferably Carbon black; the binder is at least one selected from the group consisting of resins, acrylics, vegetable oils, and mineral oils.

In the present invention, it can be seen that the above-mentioned coating layer is present in the magnetic separator material by slicing and performing metallographic analysis.

According to the present invention, in order to reduce the eddy current loss during the preparation of the magnetic isolation material, it is necessary to subject the magnetic separation material to a fracturing treatment to laminate a large-area magnetic material sheet into small pieces. The shape of the magnetic material fragments described in the present invention is not particularly limited, and may be various shapes generated by fracturing, and may be regular or irregular. Preferably, the shape of the magnetic material fragments is circular, rectangular or diamond-shaped, preferably rhombic.

According to a preferred embodiment of the invention, the length of the magnetic material fragments has a longest diagonal length of 0.005-20 mm, preferably 0.03-5 mm. For example, the longest diagonal length of the pieces of magnetic material may be 0.01 mm, 0.03 mm, 0.06 mm, 0.1 mm, 0.5 mm, 1 mm, 2 mm, 5 mm, 10 mm, 15 mm, and 20 mm. With this preferred embodiment, it is more advantageous to ensure the magnetic permeability of the magnetic isolation material and reduce its loss value.

According to a preferred embodiment of the invention, the distance (length) between two adjacent pieces of magnetic material, i.e. the size of the air gap between the pieces of magnetic material, ranges from 0.01 to 20 μm, further preferably from 0.1 to 3 μm. When the magnetic material fragments are regular patterns, the distance between two adjacent magnetic material fragments refers to the distance between adjacent parallel sides of two magnetic material fragments of the same magnetic material sheet layer, when the magnetic When the material fragments are irregular patterns, the distance between two adjacent pieces of magnetic material refers to the size (length) at which the distance between the two pieces of magnetic material of the same magnetic material sheet layer is the largest.

In the present invention, the first adhesive layer, the second adhesive layer and the double-sided adhesive layer may be existing adhesives having an insulating and bonding function, for example, may be an insulating adhesive. Preferably, the first adhesive layer, the second adhesive layer and the double-sided adhesive layer are acrylic rubber, synthetic rubber or silica gel. The double-sided tape can be glue or tape.

In the present invention, it is preferable that the first adhesive layer, the second adhesive layer, and the double-sided adhesive layer have a thickness of 3 to 20 μm. For example, it may be 3 μm, 5 μm, 7 μm, 10 μm, 12 μm, 15 μm, and 20 μm.

In the present invention, the thickness and type of the first adhesive layer, the second adhesive layer and the double-sided adhesive layer may be the same or different.

According to the present invention, preferably, the protective film is selected from at least one of a polyimide film, a polyester film, a polytetrafluoroethylene film, and a polyethylene terephthalate film, preferably the protective film. The thickness is 2-20 μm, and more preferably 3-10 μm.

According to the present invention, preferably, the release film is selected from at least one of a polyimide film, a polyester film, a polytetrafluoroethylene film, and a polyethylene terephthalate film, preferably the leaving The thickness of the film is from 10 to 125 μm, more preferably from 40 to 80 μm.

A second aspect of the invention provides a method of preparing a magnetically permeable material, the method comprising the steps of:

(1) subjecting at least one sheet of magnetic material to heat treatment under a reducing atmosphere or an inert atmosphere;

(2) one side of the heat-treated magnetic material sheet is coated with the first coating layer, and the other uncoated surface is the exposed surface;

(3) attaching a protective film to the first coating layer by a double-sided tape, and attaching the release film to the exposed surface by a double-sided tape to obtain a magnetic material component;

(4) fracturing the magnetic material component such that the magnetic material sheet in the magnetic material component is split into a plurality of magnetic material fragments; the first coating such that a gap between the magnetic material fragments is at least partially Air filled.

A third aspect of the invention provides a method for preparing a magnetic isolation material, the preparation method comprising the steps of:

(1) subjecting at least one sheet of magnetic material to heat treatment under a reducing atmosphere or an inert atmosphere;

(2) one side of the heat-treated magnetic material sheet is coated with a second coating layer, and the other uncoated surface is a bare surface;

(3) attaching a release film to the second coating layer by a double-sided tape, and bonding a protective film to the exposed surface through a double-sided tape to obtain a magnetic material component;

(4) fracturing the magnetic material component such that the magnetic material sheet in the magnetic material component is split into a plurality of magnetic material fragments; the second coating is such that a gap between the magnetic material fragments is at least partially Air filled.

A fourth aspect of the invention provides a method for preparing a magnetic isolation material, the preparation method comprising the steps of:

(1) subjecting at least one sheet of magnetic material to heat treatment under a reducing atmosphere or an inert atmosphere;

(2) coating the first coating layer and the second coating layer on both sides of the heat-treated magnetic material sheet;

(3) attaching a protective film to the first coating layer by a double-sided tape, and bonding the release film to the second coating layer by a double-sided tape to obtain a magnetic material component;

(4) fracturing the magnetic material component such that the magnetic material sheet in the magnetic material component is split into a plurality of magnetic material fragments; the first coating and the second coating are such that between the magnetic material fragments The void is at least partially filled with air.

In the above-described method of the present invention, the coating may be applied only to one side of the heat-treated magnetic material sheet, or may be coated on both sides of the heat-treated magnetic material sheet. The specific composition of the coating layer (first coating layer and/or second coating layer) of the present invention is not particularly limited as long as the gap between the magnetic material fragments can be at least partially filled with air during the fracturing process (ie, It is sufficient that the gap between the pieces of the magnetic material is blocked by the double-sided tape.

According to the preparation method provided by the present invention, the selection of the magnetic material is as described above, and details are not described herein again.

In the present invention, preferably, the magnetic material sheet is a coil. This preferred embodiment is more advantageous in ensuring high production speeds and low production costs.

According to the method provided by the present invention, preferably, the magnetic material sheet has a thickness of 10 to 35 μm. For example, the thickness of the magnetic material sheet is 10 μm, 15 μm, 20 μm, 23 μm, 25 μm, 27 μm, 30 μm, and 35 μm. More preferably, when the magnetic material is an amorphous magnetic alloy material, the thickness of the magnetic material sheet is 15 μm-30 μm, for example, 15 μm, 20 μm, 23 μm, 25 μm, 27 μm, 30 μm; when the magnetic material is a nanocrystalline magnetic alloy material, the magnetic material The thickness of the sheet is from 15 μm to 25 μm, for example, 15 μm, 20 μm, 23 μm, and 25 μm.

According to a preferred embodiment of the invention, the sheet of magnetic material has a width of 10 to 213 mm, preferably 30 to 100 mm. For example, the width of the magnetic material sheet is 20 mm, 50 mm, 60 mm, 142 mm, 170 mm, 200 mm.

In the present invention, at least one magnetic material sheet is subjected to heat treatment under a reducing or inert atmosphere, the magnetic permeability and electrical resistivity of the magnetic material can be improved, and the material brittleness is increased to facilitate subsequent processing. In addition, it is also guaranteed that the material will not be oxidized during the heat treatment. In the step (1), the reducing atmosphere may be provided by a reducing gas and optionally an inert gas, which may be supplied by an inert gas. Preferably, the reducing gas is hydrogen. The inert gas may be at least one of nitrogen, argon, helium and neon, preferably nitrogen.

According to a preferred embodiment of the present invention, the reducing atmosphere is provided by hydrogen gas and an inert gas, preferably, the volume concentration of hydrogen in the reducing atmosphere is from 0.3% to 0.5%, for example, the volume concentration of hydrogen in the reducing atmosphere is 0.3%, 0.4%, 0.5%.

In the present invention, the heat treatment conditions preferably include a temperature of 350 to 600 ° C, and can be carried out at, for example, 350 ° C, 400 ° C, 450 ° C, 480 ° C, 530 ° C, 580 ° C, 600 ° C; time is 60- 400 min, for example, heat treatment time is 60 min, 80 min, 120 min, 200 min, 300 min, 400 min. More preferably, the conditions for heat treatment of the amorphous magnetic alloy material include: a temperature of 400-550 ° C, which can be carried out at, for example, 400 ° C, 450 ° C, 480 ° C, 530 ° C, 550 ° C; time is 60-400 min, For example, the heat treatment time is 60 min, 80 min, 120 min, 200 min, 300 min, and 400 min; the conditions for heat treatment of the nanocrystalline magnetic alloy material include: the temperature is 500-600 ° C, and can be at a temperature of, for example, 500 ° C, 530 ° C, 580 ° C, 600 ° C. The process is carried out internally; the time is 60-400 min, preferably 100-200 min, for example, the heat treatment time is 60 min, 80 min, 120 min, 200 min, 300 min, 400 min.

According to a preferred embodiment of the invention, in step (1), 1-10, preferably 2-6, sheets of magnetic material are heat treated. Generally speaking, the more the number of layers of the magnetic material layer, the better the shielding effect, and the greater the density of the magnetic field accommodated, but the excessive number of layers makes the magnetic shielding material thicker, which limits the application of the magnetic isolation material to some extent. Therefore, it is preferable to heat-treat 2-6 magnetic material sheets to prepare a magnetic spacer material having 2 to 6 magnetic material sheet layers.

According to the method provided by the present invention, the method further comprises: passing a plurality of heat-treated magnetic material sheets through double-sided adhesive bonding (forming an alternating structure of a magnetic material sheet and a double-sided tape) to obtain a magnetic layer, The magnetic layer performs the step (2).

That is, the step (2) may be that the first coating layer is coated on one side of the magnetic layer, and the other uncoated surface is the exposed surface; or, the step (2) may be performed on one side of the magnetic layer. The second coating layer, the other uncoated surface is a bare surface; or, the step (2) may be to apply a first coating layer and a second coating layer on both sides of the magnetic layer.

As mentioned above, the first coating or the second coating does not flow under high temperature and mechanical action. According to the preparation method provided by the present invention, preferably, the composition and thickness of the first coating layer or the second coating layer are as described above, and are not described herein again.

The manner of forming the heat conductive or heat dissipating coating, the metal barrier coating, and the ink coating layer of the present invention is not particularly limited as long as a coating having the above composition is obtained. Those skilled in the art can make appropriate selections according to actual conditions.

Preferably, the heat conductive or heat dissipating coating may be obtained by applying a heat conductive or heat dissipating paint (for example, by a coater) to one side of the heat treated magnetic material sheet and then drying. Preferably, the thermally or thermally conductive coating comprises a nanocarbon material, a solvent and a binder, and optionally an adjuvant and a filler. The selection of the nanocarbon material and the binder is as described above, and will not be described herein. The solvent may be selected from at least one of ethyl acetate, ethanol, and water. The filler may be selected from at least one of ceramic powder, calcium titanate, barium sulfate, aluminum hydroxide, kaolin, and aluminum barium. The auxiliary agent may be selected from at least one of a surfactant, a dispersing agent, a coloring agent, a thinner, an anti-drying agent, a drying accelerator, and a flow regulating agent. The solvent in the thermally or thermally dissipative coating is volatilized and removed during subsequent drying, and the amount of the nanocarbon material and binder is such that the thermally conductive or heat dissipating coating contains the aforementioned specific amount of nanocarbon material and binder.

The heat conductive or heat dissipating paint is commercially available. For example, the nano heat conducting or heat dissipating paint used in the embodiment of the present invention is purchased from Suzhou Huan Ming Electronic Technology Co., Ltd. under the designation HM-10.

Preferably, the metal barrier coating covers the metal on one side of the heat-treated magnetic material sheet by electroplating, and it is further preferred that the metal is at least one selected from the group consisting of silver, copper, and aluminum. The present invention is not particularly limited in terms of the conditions and specific processes of the electroplating, and those skilled in the art can select according to actual conditions.

Preferably, the ink coating is obtained by coating an ink (for example, by a coater) on one side of the heat-treated sheet of magnetic material and then drying. The composition of the ink is as described above and will not be described herein. The inks are commercially available.

According to the method provided by the present invention, the selection and thickness of the double-sided tape, the protective film and the release film are as described above, and are not described herein again.

In the present invention, the fracturing process is such that the magnetic material sheet generates a chip unit due to pressure and deformation, and due to the action of the coating, the gap between the magnetic material pieces is at least partially filled with air (preferably all filled with air). In order to insulate between the pieces of magnetic material, during the fracturing process, since the magnetic material sheet has the protection of the protective film and the release film, the surface of the material maintains the overall structure.

The fracturing treatment of the present invention may be carried out by using one or more sets of shredding mechanisms having a roller shaft structure. Each of the crushing mechanisms has a cylindrical shaft, and the other roller is a cylinder. The optical axis, the pressure adjusting mechanism between the rollers is a spring pressure mechanism, a cylinder pressure mechanism or a hydraulic pressure mechanism. During the operation of the mechanism, when the thickness of the material is slightly changed or the outer diameter of the upper and lower rollers is slightly deformed, the material is subjected to The pressure remains constant or fluctuates within a very small range during the floating process of the pressure regulating mechanism, which greatly guarantees the performance stability of the final magnetically isolating material. The pattern can be circular, rectangular, diamond-shaped, In one of the other regular shapes or other irregular shapes, the tread shaft generally employs a metal roller shaft, and the optical axis may be a metal roller shaft or a rubber roller. Preferably, the positions of the different sets of roller knuckles and the steel rollers are alternately arranged, for example, the roller shaft on the first set of roller shafts is a pattern stick, the lower roller shaft is a baton, and the roller shaft on the second group of rollers is a bachelor, a lower roller The shaft is a pattern stick, the roller shaft of the third group of rollers is a pattern stick, and the lower roller shaft is a bachelor, so that the upper and lower surfaces of the cracked magnetic material can be uniformly shredded, and the performance of the magnetic isolation material is stable and reliable.

The magnetic material assembly provided by the present invention is shown in FIG.

In the present invention, the fracturing process is preferably carried out in a fracturing machine, as shown in Fig. 4, the fracturing machine comprising an upper roll 60 and a lower roll 62, the upper roll being a pattern roll having a projection 61 The lower roller is a flat roller shaft. The speed and pressure of the fracturing machine are adjustable.

In the present invention, the shape of the protrusion 61 may determine the shape of the magnetic material chip. Preferably, the end surface of the protrusion 61 is one of a rectangle, a circle, and a diamond, preferably a diamond. Accordingly, the shape of the formed magnetic material fragments is respectively rectangular, circular or diamond-shaped, preferably rhombic.

In the present invention, preferably, the number of fracturings is 1-10 times, for example, the number of fracturings is 1, 3, 5, 7, 10, preferably 6-10, such as the number of fracturing It is 6 times, 7 times, 10 times.

The longest diagonal length of the magnetic material fragments and the distance between two adjacent magnetic material fragments are as described above, and will not be described herein.

A fifth aspect of the present invention provides a magnetic spacer material prepared by the production method of the present invention. The magnetic isolation material has better reflection effect on the magnetic field, can effectively shield the interference of the wireless charging working magnetic field on the electronic device components, and the magnetic field generated by the internal components of the electronic device cannot interfere with the wireless charging working environment, and the magnetic permeability Higher, the magnetic permeability of the magnetic isolation material is much higher than that of air, and the magnetic field is more easily passed through the magnetic isolation material, providing an efficient path for the wirelessly charged working magnetic field and improving the charging efficiency. In addition, the magnetic layer of the magnetic separator has a fragment structure and an air gap between the fragments, which can effectively reduce the eddy current loss generated during operation, reduce the temperature rise during operation of the electronic device, and the preferred heat conduction or heat dissipation coating has good performance. The thermal or thermal performance of the heat can quickly transfer the heat generated during operation.

The sixth aspect of the invention provides the application of the magnetic isolation material of the invention in a wireless charging module or a near field communication module. Specifically, the magnetic isolation material is suitable for the transmitting end and the receiving end of the wireless charging, and is also applicable to the receiving device of the NFC antenna and the RFID antenna of the mobile terminal. The magnetically dissipative material can be applied in a frequency range of 0 Hz to 3 GHz.

The invention will be described in detail below by way of examples. In the following embodiments,

Iron-based amorphous alloy material was purchased from Hitachi Metals Investment (China) Co., Ltd. under the trade name 1K101;

Iron-based nanocrystalline alloy materials were purchased from Hitachi Metals Investment (China) Co., Ltd. under the trade name 1K107;

Double-sided adhesive was purchased from Shanghai Green Her New Material Technology Co., Ltd., and the grade was LH-NP3;

The release film was purchased from Shanghai Luhe New Material Technology Co., Ltd., and the grade was PET-75;

The protective film was purchased from Shanghai Green Her New Material Technology Co., Ltd. under the brand number PTG0503-25;

Nano thermal or thermal coatings were purchased from Suzhou Huan Ming Electronic Technology Co., Ltd. under the brand name HM-10;

The ink was purchased from Suzhou Huan Ming Electronic Technology Co., Ltd., and the grade was HMYM-93;

The protrusion of the upper roller of the fracturing machine is a diamond shape with a side length of 1 mm;

The distance between adjacent pieces of magnetic material was determined by slicing and performing metallographic analysis.

Example 1

(1) The iron-based nanocrystalline alloy material (coil, thickness 20 μm, width 60 mm) was subjected to hydrogenation heat treatment at 530 ° C for 120 min in argon gas containing 0.5% by volume of hydrogen;

(2) each nanocrystalline alloy material obtained in the step (1) is bonded together through a 3 μm double-sided tape to form a magnetic layer containing a layer structure of four layers of magnetic material;

(3) Applying a nano-heat-conducting or heat-dissipating coating having a heat conductivity or a heat dissipation coefficient of 10 w/m·k to one side of the magnetic layer obtained in the step (2) on a coater to form a 5 μm heat-conducting or heat-dissipating coating (first coating);

(4) The 4 μm protective film is pasted through the 3 μm double-sided adhesive to obtain the heat conductive or heat-dissipating coating obtained in the step (3);

(5) a 75 μm release film is attached to the other side of the magnetic layer through a 10 μm double-sided tape;

(6) The magnetic material component obtained in the step (5) is fractured 7 times in a fracturing machine at a pressure of 0.5 MPa, so that the magnetic material sheet layer in the magnetic material component is split into a plurality of fragment units, and is separated. Magnetic material S1. The presence of the first coating results in an air gap between the pieces of magnetic material.

Comparative example 1

According to the method of Embodiment 1, the difference is that step (3) is not included, specifically:

(1) The iron-based nanocrystalline alloy material (coil, thickness 20 μm, width 60 mm) was subjected to hydrogenation heat treatment at 530 ° C for 120 min in argon gas containing 0.5% by volume of hydrogen;

(2) each nanocrystalline alloy material obtained in the step (1) is bonded together through a 3 μm double-sided tape to form a magnetic layer containing a layer structure of four layers of magnetic material;

(3) attaching a 4 μm protective film to one side of the magnetic layer obtained in the step (3) through a 3 μm double-sided tape;

(4) a 75 μm release film is attached to the other side of the magnetic layer through a 10 μm double-sided tape;

(5) Fracturing was carried out in accordance with step (6) of Example 1. The magnetic spacer material D1 was obtained.

Comparative example 2

According to the method of Embodiment 1, the step (3) is not included, and the fracturing process is high temperature fracturing, specifically:

(1) The iron-based nanocrystalline alloy material (coil, thickness 20 μm, width 60 mm) was subjected to hydrogenation heat treatment at 530 ° C for 120 min in argon gas containing 0.5% by volume of hydrogen;

(2) each nanocrystalline alloy material obtained in the step (1) is bonded together through a 3 μm double-sided tape to form a magnetic layer containing a layer structure of four layers of magnetic material;

(3) attaching a 4 μm protective film to one side of the magnetic layer obtained in the step (3) through a 3 μm double-sided tape;

(4) a 75 μm release film is attached to the other side of the magnetic layer through a 10 μm double-sided tape;

(5) The magnetic material component obtained in the step (4) is subjected to high-temperature fracturing 7 times in a high-temperature fracturing machine (the protrusion of the upper roll is a diamond shape) at 150 ° C and a pressure of 0.5 MPa, so that the magnetic material component is The magnetic material sheet layer is split into a plurality of chip units, and the double-sided tape partially flows into the crack between the chip units under the action of temperature. The magnetic spacer material D2 was obtained. There is no air gap between each fragment unit.

Example 2

(1) The iron-based nanocrystalline alloy material (coil, thickness 20 μm, width 60 mm) was subjected to hydrogenation heat treatment at 600 ° C for 100 min in a hydrogen atmosphere containing 0.4% by volume of hydrogen;

(2) each nanocrystalline alloy material obtained in the step (1) is bonded together by a 3 μm double-sided tape to form a magnetic layer containing a 6-layer magnetic material sheet layer structure;

(3) Applying a nano-heat-conducting or heat-dissipating coating having a heat conductivity or a heat dissipation coefficient of 10 w/m·k to one side of the magnetic layer obtained in the step (2) on a coater to form a heat-conductive or heat-dissipating coating of 8 μm (second coating);

(4) a 75 μm release film is attached to the obtained heat conductive or heat-dissipating coating layer of the step (3) through a 10 μm double-sided tape;

(5) a 4 μm protective film is attached to the other side of the magnetic layer through a 3 μm double-sided tape;

(6) The magnetic material component obtained in the step (5) is fractured 6 times in a fracturing machine at a pressure of 0.5 MPa, so that the magnetic material sheet layer in the magnetic material component is split into a plurality of fragment units, and is separated. Magnetic material S2. The presence of the second coating results in an air gap between the pieces of magnetic material.

Example 3

(1) The iron-based nanocrystalline alloy material (coil, thickness 20 μm, width 60 mm) was subjected to hydrogenation heat treatment at 500 ° C for 200 min in a argon gas containing 0.3% by volume of hydrogen;

(2) each of the nanocrystalline alloy materials obtained in the step (1) is bonded together by a 4 μm double-sided tape to form a magnetic layer containing two layers of a magnetic material sheet layer;

(3) Applying a nanometer heat conduction or heat dissipation coating having a heat conduction or heat dissipation coefficient of 10 w/m·k on both sides of the magnetic layer obtained in the step (2) on a coater to form a first heat conduction or heat dissipation coating of 3 μm ( a first coating) and a 3 μm second heat or heat dissipation coating (second coating);

(4) attaching a 75 μm release film to one side of the obtained second heat conduction or heat dissipation coating layer of the step (3) through a 10 μm double-sided tape;

(5) a 4 μm protective film is attached to one side of the first heat conducting or heat dissipating coating layer obtained in the step (3) through a 3 μm double-sided tape;

(6) The magnetic material component obtained in the step (5) is fractured 5 times in a fracturing machine at a pressure of 0.5 MPa, so that the magnetic material sheet layer in the magnetic material component is split into a plurality of fragment units, and is separated. Magnetic material S3. The presence of the first coating and the second coating results in an air gap between the pieces of magnetic material.

Example 4

The procedure of Example 1 was followed except that the temperature of the heat treatment was 450 °C. A magnetically permeable material S4 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 5

The procedure of Example 1 was followed except that the temperature of the heat treatment was 630 °C. A magnetically permeable material S5 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 6

The procedure of Example 1 was followed except that the heat treatment time was 60 min. A magnetically permeable material S6 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 7

The procedure of Example 1 was followed except that the heat treatment time was 300 min. The magnetic spacer material S7 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 8

The method of Example 1 was followed, except that the thickness of the heat conducting or heat dissipating coating formed in the step (3) was 1 μm. A magnetically permeable material S8 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 9

The method of Example 1 was followed except that the thickness of the heat conducting or heat dissipating coating formed in the step (3) was 10 μm. A magnetically permeable material S9 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 10

According to the method of Example 1, except that the step (2) is not included, the one-layer magnetic material sheet obtained by the hydrogenation heat treatment is subjected to the step (3), that is, the magnetic layer includes one layer of the magnetic material sheet. The magnetic spacer material S10 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 11

According to the method of Example 1, except that the magnetic layer containing 10 layers of the magnetic material sheet layer was formed in the step (2), that is, the magnetic layer included 10 sheets of the magnetic material. The magnetic spacer material S11 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 12

According to the method of Embodiment 1, except that in step (3), metal Ag is plated on one side of the magnetic layer obtained in the step (2) by electroplating to form a 5 μm metal barrier coating (first coating) Floor). The magnetic spacer material S12 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 13

(1) The iron-based amorphous alloy material (coil, thickness 25 μm, width 60 mm) was subjected to hydrogenation heat treatment at 460 ° C for 120 min in argon gas containing 0.5% by volume of hydrogen;

(2) each amorphous alloy material obtained in the step (1) is bonded together through a 3 μm double-sided tape to form a magnetic layer containing a layer structure of four layers of magnetic material;

(3) Applying a nano-heat-conducting or heat-dissipating coating having a heat conductivity or a heat dissipation coefficient of 10 w/m·k to one side of the magnetic layer obtained in the step (2) on a coater to form a 5 μm heat-conducting or heat-dissipating coating (first coating);

(4) The 4 μm protective film is pasted through the 3 μm double-sided adhesive to obtain the heat conductive or heat-dissipating coating obtained in the step (3);

(5) a 75 μm release film is attached to the other side of the magnetic layer through a 10 μm double-sided tape;

(6) The magnetic material component obtained in the step (5) is fractured 7 times in a fracturing machine at a pressure of 0.5 MPa, so that the magnetic material sheet layer in the magnetic material component is split into a plurality of fragment units, and is separated. Magnetic material S13. The presence of the first coating results in an air gap between the pieces of magnetic material.

Comparative example 3

According to the method of Embodiment 13, the difference is that step (3) is not included, specifically:

(1) The iron-based amorphous alloy material (coil, thickness 25 μm, width 60 mm) was subjected to hydrogenation heat treatment at 460 ° C for 120 min in argon gas containing 0.5% by volume of hydrogen;

(2) each amorphous alloy material obtained in the step (1) is bonded together through a 3 μm double-sided tape to form a magnetic layer containing a layer structure of four layers of magnetic material;

(3) attaching a 4 μm protective film to one side of the magnetic layer obtained in the step (3) through a 3 μm double-sided tape;

(4) a 75 μm release film is attached to the other side of the magnetic layer through a 10 μm double-sided tape;

(5) Fracturing was carried out in accordance with step (6) of Example 13. The magnetic spacer material D3 was obtained.

Example 14

According to the method of Example 13, the temperature of the heat treatment of the step (1) was 350 °C. A magnetically permeable material S14 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 15

According to the method of Example 13, the temperature of the heat treatment of the step (1) was 500 °C. The magnetic spacer material S15 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 16

The procedure of Example 13 was followed except that the heat treatment time of the step (1) was 60 min. The magnetic spacer material S16 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 17

The procedure of Example 13 was followed except that the heat treatment time of the step (1) was 300 min. The magnetic spacer material S17 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 18

The procedure of Example 13 was followed except that the thickness of the heat conducting or heat dissipating coating formed in the step (3) was 1 μm. A magnetically permeable material S18 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 19

The procedure of Example 13 was followed except that the thickness of the heat conducting or heat dissipating coating formed in the step (3) was 10 μm. The magnetic spacer material S19 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 20

According to the method of Example 13, except that the step (2) is not included, the sheet of the magnetic material obtained by the hydrothermal treatment is subjected to the step (3), that is, the magnetic layer comprises a sheet of the magnetic material. The magnetic spacer material S20 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 21

According to the method of Example 13, except that the magnetic layer containing 10 layers of the magnetic material sheet layer was formed in the step (2), that is, the magnetic layer included 10 sheets of the magnetic material. A magnetic insulating material S21 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Example 22

According to the method of Example 13, except that the heat conductive or heat-dissipating paint was changed to the ink paint in the step (3), that is, an ink coating (first coat) of 5 μm was formed. The magnetic spacer material S22 is obtained. The presence of the first coating results in an air gap between the pieces of magnetic material.

Test case

Using WK6500B impedance analyzer, test1.0 coil, test frequency is 100KHz, the prepared magnetic layer of magnetic isolation material is directed to the test coil, placed on the coil, and the resin compact of diameter about 50mm is placed on the magnetic isolation material. The inductance value, magnetoresistance and quality factor of the magnetic separator obtained by the above examples and comparative examples were tested. The results are shown in Table 1.

Table 1

Example number	Inductance value / μH	Magnetoresistance / mΩ	Quality factor Q
Example 1	11.79	83	97

Comparative example 1	11.29	96	81
Comparative example 2	11.08	99	80
Example 2	13.12	79	116
Example 3	7.76	168	59
Example 4	11.71	90	95
Example 5	11.35	91	89
Example 6	11.51	90	85
Example 7	11.66	91	87
Example 8	11.77	88	94
Example 9	11.81	80	101
Example 10	6.19	197	40
Example 11	13.76	75	125
Example 12	11.58	87	92
Example 13	11.96	201	79
Comparative example 3	11.39	214	65
Example 14	11.89	207	77
Example 15	11.73	205	73
Example 16	11.93	212	70
Example 17	11.83	209	70
Example 18	11.94	206	78
Example 19	11.94	198	85
Example 20	5.23	312	31
Example 21	13.26	97	94
Example 22	11.86	207	77

The method provided by the invention increases the heat treatment temperature within a proper range to help the material release the internal stress better, improve the crystallinity of the nanocrystalline alloy material, improve the quality factor of the magnetic isolation material, and reduce the magnetic resistance of the magnetic isolation material; By using a coating, the gap between the pieces of magnetic material is at least partially filled with air, reducing eddy current losses in the work process. Increasing the thickness of the heat-conducting or heat-dissipating coating within an appropriate range helps to reduce the magnetic resistance of the magnetically isolating material and improve the quality factor. The magnetic isolation material prepared by the preparation method of the invention has better magnetic permeability and heat conduction or heat dissipation performance, and the material itself consumes less magnetic field.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the invention is not limited thereto. Within the scope of the technical idea of the present invention, various simple modifications can be made to the technical solutions of the present invention, including various technical features combined in any other suitable manner, and these simple variations and combinations should also be regarded as the disclosure of the present invention. All fall within the scope of protection of the present invention.

Claims (14)

1. A magnetic shielding material, comprising: a magnetic layer; and a protective film and a release film disposed on different sides of the magnetic layer, wherein the magnetic layer contains at least one magnetic material thin layer The magnetic material foil layer contains a plurality of magnetic material fragments, and a gap between the magnetic material fragments is at least partially filled with air; a first adhesive layer is disposed between the protective film and the magnetic layer, and the release film A second adhesive layer is disposed between the magnetic layer and the magnetic layer.
2. The magnetic flux barrier material according to claim 1, wherein, in the magnetic layer, the number of the magnetic material sheet layers is 1-10 layers, preferably 2-6 layers;

   Preferably, a double-sided adhesive layer is disposed between adjacent layers of the magnetic material sheets;

   Preferably, the magnetic material sheet layer has a thickness of 10 to 35 μm and a width of 10 to 213 mm, and more preferably, the magnetic material sheet layer has a thickness of 15 to 30 μm and a width of 30 to 100 mm;

   Preferably, the magnetic material is an Fe-based, Co-based or Ni-based amorphous or nanocrystalline magnetic alloy material, further preferably an Fe-based amorphous or nanocrystalline magnetic alloy material.
3. The magnetic flux barrier material according to claim 1 or 2, wherein the magnetic spacer material further comprises a first coating layer disposed between the magnetic layer and the first adhesive layer, and/or disposed on the magnetic material a second coating between the layer and the second subbing layer; wherein the first coating and/or the second coating are each independently selected from a heat conducting or heat dissipating coating, a metal barrier coating, and an ink coating At least one of them;

   Preferably, the thickness of the first coating layer and/or the second coating layer is each independently from 1 to 20 μm, further preferably from 3 to 8 μm.
4. The magnetic spacer material according to claim 3, wherein

   The heat conduction or heat dissipation coating has a heat conduction or heat dissipation coefficient of 10 to 200 W/(m·k). Preferably, the heat conduction or heat dissipation coating layer contains a nano carbon material and a binder, preferably, the nano carbon material. At least one selected from the group consisting of carbon black, graphene, and ceramic powder; the binder is selected from the group consisting of a resin and/or an acrylic acid;

   The metal barrier coating is selected from at least one of a silver coating, a copper coating, and an aluminum coating.
5. The magnetic flux barrier material according to any one of claims 1 to 4, wherein the first adhesive layer, the second adhesive layer and the double-sided adhesive layer are each independently selected from at least acrylic rubber, synthetic rubber and silica gel. a preferred thickness of the first adhesive layer, the second adhesive layer and the double-sided adhesive layer are each independently 3-20 μm;

   Preferably, the protective film is selected from at least one of a polyimide film, a polyester film, a polytetrafluoroethylene film, and a polyethylene terephthalate film, and preferably the protective film has a thickness of 2 -20μm;

   Preferably, the release film is selected from at least one of a polyimide film, a polyester film, a polytetrafluoroethylene film, and a polyethylene terephthalate film, preferably a thickness of the release film. It is 10-125 μm.
6. A method for preparing a magnetic isolation material, characterized in that the preparation method comprises the following steps:

   (1) subjecting at least one sheet of magnetic material to heat treatment under a reducing atmosphere or an inert atmosphere;

   (2) one side of the heat-treated magnetic material sheet is coated with the first coating layer, and the other uncoated surface is the exposed surface;

   (3) attaching a protective film to the first coating layer by a double-sided tape, and attaching the release film to the exposed surface by a double-sided tape to obtain a magnetic material component;

   (4) fracturing the magnetic material component such that the magnetic material sheet in the magnetic material component is split into a plurality of magnetic material fragments; the first coating such that a gap between the magnetic material fragments is at least partially Air filled.
7. A method for preparing a magnetic isolation material, characterized in that the preparation method comprises the following steps:

   (1) subjecting at least one sheet of magnetic material to heat treatment under a reducing atmosphere or an inert atmosphere;

   (2) one side of the heat-treated magnetic material sheet is coated with a second coating layer, and the other uncoated surface is a bare surface;

   (3) attaching a release film to the second coating layer by a double-sided tape, and bonding a protective film to the exposed surface through a double-sided tape to obtain a magnetic material component;

   (4) fracturing the magnetic material component such that the magnetic material sheet in the magnetic material component is split into a plurality of magnetic material fragments; the second coating is such that a gap between the magnetic material fragments is at least partially Air filled.
8. A method for preparing a magnetic isolation material, characterized in that the preparation method comprises the following steps:

   (1) subjecting at least one sheet of magnetic material to heat treatment under a reducing atmosphere or an inert atmosphere;

   (2) coating the first coating layer and the second coating layer on both sides of the heat-treated magnetic material sheet;

   (3) attaching a protective film to the first coating layer by a double-sided tape, and bonding the release film to the second coating layer by a double-sided tape to obtain a magnetic material component;

   (4) fracturing the magnetic material component such that the magnetic material sheet in the magnetic material component is split into a plurality of magnetic material fragments; the first coating and the second coating are such that between the magnetic material fragments The void is at least partially filled with air.
9. The production method according to any one of claims 6 to 8, wherein in the step (1), 1-10, preferably 2 to 6 sheets of the magnetic material are subjected to heat treatment; the method further comprising after the plurality of heat treatments The magnetic material sheet is adhered by double-sided bonding to obtain a magnetic layer, and the magnetic layer is subjected to the step (2);

   Preferably, the magnetic material sheet has a thickness of 10 to 35 μm and a width of 10 to 213 mm, and more preferably, the magnetic material sheet layer has a thickness of 15 to 30 μm and a width of 30 to 100 mm;

   Preferably, the magnetic material is an Fe-based, Co-based or Ni-based amorphous or nanocrystalline magnetic alloy material, further preferably an Fe-based amorphous or nanocrystalline magnetic alloy material.
10. The production method according to any one of claims 6 to 9, wherein the reducing atmosphere is supplied by hydrogen gas and optionally an inert gas, and the inert atmosphere is supplied by an inert gas;

    Preferably, the conditions of the heat treatment include a temperature of 350 to 600 ° C and a time of 60 to 400 min.
11. The production method according to any one of claims 6 to 10, wherein the first coating layer and/or the second coating layer are each independently selected from a heat conductive or heat dissipation coating, a metal barrier coating, and an ink coating layer. At least one of them;

    Preferably, the thickness of the first coating layer and/or the second coating layer is each independently from 1 to 20 μm, further preferably from 3 to 8 μm;

    Preferably, the heat conduction or heat dissipation coating has a heat conduction or heat dissipation coefficient of 10 to 200 W/(m·k), preferably, the heat conduction or heat dissipation coating layer contains a nano carbon material and a binder, preferably, the The heat conductive or heat dissipating coating is obtained by applying a coating containing a nanocarbon material, a solvent and a binder to one side of the heat treated magnetic material sheet, and then drying; preferably, the nano carbon material is selected from the group consisting of carbon black, At least one of graphene and ceramic powder; the binder is selected from the group consisting of a resin and/or an acrylic acid; and the solvent is selected from at least one of ethyl acetate, ethanol, and water;

    Preferably, the metal shielding coating is applied to one side of the heat-treated magnetic material sheet by electroplating; preferably, the metal is selected from at least one of silver, copper and aluminum;

    Preferably, the ink coating is applied to one side of the heat-treated magnetic material sheet by a coater and then dried.
12. The preparation method according to any one of claims 6 to 11, wherein the double-sided tape is at least one selected from the group consisting of an acrylic rubber, a synthetic rubber, and a silica gel, and preferably the double-sided tape has a thickness of 3 to 20 μm. ;

    Preferably, the protective film is selected from at least one of a polyimide film, a polyester film, a polytetrafluoroethylene film, and a polyethylene terephthalate film, and preferably the protective film has a thickness of 2 -20μm;

    Preferably, the release film is selected from at least one of a polyimide film, a polyester film, a polytetrafluoroethylene film, and a polyethylene terephthalate film, preferably a thickness of the release film. It is 10-125 μm.
13. A magnetically permeable material prepared by the production method according to any one of claims 6-12.
14. The use of the magnetic isolation material of any one of claims 1-5 and 13 in a wireless charging module or a near field communication module.

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