KR20180107661A - Housing for electromagnetic shielding - Google Patents

Abstract

The present invention relates to a housing for electromagnetic shielding. The present invention provides a plastic housing including: a body made of plastic; and a shielding layer composed of at least one of Al, Si, V, Cr, Fe, Co, Ni, Cu, Zn, Ag and Sn, in which at least a portion of a surface of the body is coated with the shielding layer. A part of the shielding layer penetrates into the plastic surface and solidified therein. As described above, according to the present invention, a metal or an alloy coating layer can be attached to a plastic surface with high adhesion strength. Accordingly, the present invention can constitute the housing for electronic components by using a light reinforced plastic, and the plastic surface can be coated with a metal or an alloy having the shielding function. Since the ratio of the relatively heavy metal or alloy in the housing according to the present invention is very low, it is possible to provide a housing which is lighter than the housing of the conventional electronic component and has the electromagnetic shielding function.

Description

[0001] HOUSING FOR ELECTROMAGNETIC SHIELDING [0002]

The present invention relates to a housing for electromagnetic shielding.

Electromagnetic wave shielding refers to shielding the noise generated inside the electronic component from being radiated outside the case or from the outside. Electronic components that generate a large amount of electromagnetic waves or are sensitive to external electromagnetic waves must be shielded from electromagnetic waves. For this purpose, the housing of the electronic component is made to have electromagnetic shielding ability.

On the other hand, electromagnetic shielding can be roughly classified into two types.

First, there is magnetic shielding. A method of using a material having a high magnetic permeability for shielding a magnetic field to allow a magnetic field line to pass through a magnetic shield portion having a low magnetic resistance is used. At this time, the shielding material is mainly made of iron or permalloy, and the thicker the plate, the greater the effect.

Second, there is electric field shielding. A method of applying a zinc coating, a plating or a conductive coating on the surface of a metal case or a plastic case for shielding an electric field, and a method of imparting conductivity to the plastic itself used in the case.

As described above, a conductive metal is mainly used as a material for electromagnetic shielding. For electromagnetic shielding, there may be a method of constructing the housing of the electronic component with metal, but this increases the weight of the electronic component.

On the other hand, the main frame of the electronic part housing is made of a lightweight plastic in a state, and there is a method of coating a metal on the plastic surface. However, since the adhesion of the metal to the plastic is low, there is a problem that the metal is easily peeled off from the plastic. Particularly, there is a problem that the metal coated on the plastic surface is peeled off due to the thermal shock due to the temperature change.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electronic component housing that is lighter than conventional housings and has excellent shielding ability in order to solve the above problems.

Specifically, the present invention provides an electronic component housing having an electromagnetic shielding layer that can be attached to a plastic surface with high adhesion strength, and a method of manufacturing the same.

In order to achieve the above object, the present invention has a shield layer having a high adhesion strength to a plastic surface.

In a specific embodiment, the present invention provides a shielding structure comprising at least one of a body made of plastic and at least one of Al, Si, V, Cr, Fe, Co, Ni, Cu, Zn, Ag and Sn, And a part of the shielding layer is formed by solidification while being penetrated to the plastic surface.

In one embodiment, the thickness of the shielding layer may be between 5 and 300 mu m.

In one embodiment, the sheet resistance of the shielding layer may be 0.01 Ω / sq or less.

In one embodiment, the porosity of the shielding layer may be less than or equal to 5%.

In one embodiment, the area of the surface of the body where the shielding layer is coated may have irregularities. Thus, the adhesion strength of the shielding layer can be improved.

In one embodiment, the shielding layer may comprise a plurality of layers. This makes it possible to take advantage of each of the materials constituting the plurality of layers.

The method may further include the steps of: performing a surface treatment on the body so that concavities and convexities are formed on the surface of the body made of plastic; and a step of coating the surface of the body with Al, Si, V, Cr, Fe, Co, Ni, Ag and Sn, and the injection speed of the molten metal or alloy is 300 to 500 m / s. The electromagnetic shielding for a plastic housing Layer coating method.

As described above, according to the present invention, a metal or alloy coating layer can be attached to a plastic surface with high adhesion strength. Accordingly, the present invention can form a main material constituting a housing for an electronic part as a light-weight reinforced plastic, and can coat a metal or an alloy that shields the plastic surface.

Since the ratio of the relatively heavy metal or alloy in the housing according to the present invention is very low, according to the present invention, it is possible to provide a housing which is lighter than the housing of the conventional electronic component and has the electromagnetic shielding function.

1 is a perspective view illustrating an electronic component housing according to an embodiment of the present invention.
2 is a cross-sectional view taken along line A-A 'of FIG.
Figs. 3 and 4 are enlarged views of a portion B in Fig. 2.
5 is a sectional view of a housing including a body made of a concavo-convex structure.
6 is a cross-sectional photograph of a housing according to an embodiment of the present invention.
FIG. 7 is a graph showing the shielding performance test results of the housing shown in FIG.
8 is a cross-sectional view of a housing including a shielding layer formed of a plurality of layers.
9 is a cross-sectional photograph of a housing including a shielding layer made of a plurality of layers.
10 is a graph showing the shielding performance test results of the housing shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals are used to designate identical or similar elements, and redundant description thereof will be omitted. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. , ≪ / RTI > equivalents, and alternatives.

Terms including ordinals, such as first, second, etc., may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another.

The singular expressions include plural expressions unless the context clearly dictates otherwise.

In the present application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

FIG. 1 is a perspective view showing an electronic component housing according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line A-A 'in FIG.

The housing serves to physically or chemically protect components built in the housing from the outside. The housing of Fig. 1 allows the electronic component to form a cylindrical outer appearance. Although the cylindrical housing is described in this specification, the shape of the housing is not limited to this, and may vary depending on the form of the electronic part.

Referring to FIG. 2, the housing is formed by a plurality of outer walls, and the interior of the housing is an empty space. Components constituting an electronic component are disposed at positions where the empty space is formed. The outer walls absorb external impacts and prevent foreign material from entering the interior of the housing. The surface of the outer walls may be coated with a shielding layer.

Figs. 3 and 4 are enlarged views of a portion B in Fig. 2.

Referring to FIG. 3, the outer wall of the housing according to an embodiment of the present invention may include a plastic body 110 and a shielding layer 120 coated on the body surface.

Here, the surface of the body 110 may have an outer surface facing the outside of the housing and an inner surface facing the inside of the housing. The shielding layer 120 may be coated on at least one of the outer surface and the inner surface of the body 110.

For example, referring to FIG. 3, the shielding layer 120 may be coated on the outer surface of the body 110. In this case, the shielding layer 120 is disposed to face outward, and the outer appearance of the housing is determined depending on the material of the shielding layer 120.

4, the shielding layer 120 may be coated on the inner surface of the body 120. In addition, In this case, the shielding layer 120 is disposed to face inward, and the outer appearance of the housing is determined according to the material of the plastic forming the body 110.

On the other hand, although not shown, the shielding layer 120 may be disposed on each of the outer and inner sides of the body.

Hereinafter, the body 110 and the shielding layer 120 will be described in detail.

The body 110 is a basic framework for determining the shape of the housing according to the present invention. The body 110 may be formed into various shapes depending on the shape of the electronic component. The body 110 may be made of plastic to reduce the weight of the housing. In particular, the plastic is made of acrylonitrile-butadiene-styrene (ABS), polypropylene (PP), polyethylene (PE), polystyrene (PS), polycarbonate (PC), polyphenylene oxide (PPO) A thermoplastic resin comprising at least one of polyoxyethylene (POM), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), liquid crystal polymers (LCP) A thermosetting resin containing at least one of phenol, urea, melamine, alkyd, unsaturated polyester, epoxy, silicone and polyurethane, or a composite resin in which a thermoplastic resin and a thermosetting resin are mixed.

Meanwhile, in order to increase the strength of the housing, the plastic may include additives. Here, the additive may be at least one of glass fiber, carbon nanotubes, graphene, graphene nanoplatelets, carbon black, graphite, nanofiber, nanocellulose and talc. The additive is present in an amount of from 1 to 50 wt. % Can be added. The content of the additive in the plastic is 1 wt. %, The effect of increasing the strength of the plastic is small. %, There is a problem in that flowability is low during injection molding and processing becomes difficult. Preferably, the content of the additive is 30 wt. %. ≪ / RTI >

The specific gravity of the plastic is 1.1 to 1.5, which is lighter than the aluminum alloy (specific gravity 2.7) which has been used as a conventional metal housing. Therefore, when the plastic is used as the housing of the electronic component, the electronic component can be made lighter. However, since the plastic has almost no electromagnetic shielding ability, the shielding layer 120 must be coated on the plastic surface. Hereinafter, the shielding layer 120 will be described in detail.

The shielding layer 120 is a metal or an alloy containing at least one of Cu, Ni, Al, Zn, Sn, Fe, Co, Cr,

The shielding layer 120 is melted and coated on the surface of the body 110 to be coated. Here, the molten injection is a technique of forming a metal coating film by spraying a molten metal onto the surface of an object at a high speed.

Since the molten metal is very hot, when a molten metal contacts the surface of the body 110, a part of the surface of the body 110 can be melted. As a result, the molten metal can penetrate the surface of the body 110. Referring to FIG. 3, the molten metal solidifies into the state (120a) in which the surface of the body 110 penetrates.

As described above, since a part of the shielding layer 120 penetrates the surface of the body 110, the shielding layer 120 can have a high adhesion strength.

Here, the shielding layer 120 should have a certain level of adhesion strength and a shielding ability higher than a certain level. Hereinafter, the shielding layer 120 will be described in each of the above two aspects.

In this specification, the adhesion strength was measured according to the test standard ASTM D4541-09e1, the test apparatus was PosiTest AT (Defelsko-USA), and the test speed was 1 MPa / s. Specifically, the test method was a pull-off test method in which a 2-type epoxy dolly (diameter 20 mm) was adhered to a metal film coated on a plastic and cured, and the attached dolly was pulled to measure the pressure when dropped. The bond strengths referred to herein are all the bond strengths measured in the manner described above.

On the other hand, the porosity of the shielding layer 120, which affects the adhesion strength and the shielding ability, was measured using an image analysis program (Gwyddion) after photographing an SEM (Scanning Electron Microscope) image of a metal coating film using an electron microscope . The porosity referred to herein is the porosity measured in the above-described manner.

First, the adhesive strength of the shielding layer 120 is described. The adhesion strength of the shielding layer 120 should be not less than 2.5 MPa. When the adhesion strength of the shielding layer 120 is less than 2.5 MPa, the shielding layer 120 can be peeled off by thermal shock occurring between -40 and 95 캜.

There are two main factors that can affect the above bond strength. Specifically, it is the porosity of the shielding layer 120 and the surface state of the body 110. Hereinafter, the above two factors will be described in detail.

First, the porosity of the shielding layer 120 should be less than 5%. When the porosity exceeds 5%, the adhesion strength of the shielding layer 120 may be less than 2.5 MPa, and the contact surface with oxygen is widened, so that the oxidation of the shielding layer 120 is accelerated. Oxidation of the shielding layer 120 is a factor that reduces the adhesion strength of the shielding layer 120, so that it is desirable to minimize it. On the other hand, the porosity of the shielding layer 120 can be controlled by the injection speed of the molten metal when the shielding layer 120 is coated. This will be described later together with the coating method.

However, there may be a specific metal or alloy having a high adhesion with a specific material constituting the body 110. Specifically, a metal or an alloy having an excellent adhesion to a plastic surface may have an adhesion strength of 2.5 MPa or more even if the porosity exceeds 5%. For example, when Zn metal is coated on the polycarbonate surface, the shielding layer 120 has an adhesion strength of 2.5 MPa or more even if the shielding layer 120 has a porosity of 10% to 15%. However, when the porosity is more than 5%, the oxidation of the shielding layer 120 and the increase of the sheet resistance may be problematic. Therefore, the porosity is preferably 5% or less.

On the other hand, when the porosity of the shielding layer 120 is 3% or less, the adhesion strength of the shielding layer 120 further increases. Concretely, when the porosity of the shielding layer 120 is 3% or less, the adhesion strength of the shielding layer 120 may be 6.0 MPa or more.

Secondly, as the surface of the body 110 is roughly formed, the contact area with the shielding layer 120 increases and the adhesion strength increases. A concavo-convex structure may be formed on the surface of the body 110, independently of penetration of the shielding layer 120 to the surface of the body 110, in order to increase the contact area between the body 110 and the shielding layer 120.

5, a plurality of irregularities 110a may be formed on the surface of the body 110. In addition, The irregularities 110a increase the contact area between the body 110 and the shielding layer 120, thereby increasing the adhesion strength of the shielding layer 120. [ A method of forming the concave and convex portions 110a on the surface of the body 110 will be described later.

As described above, the adhesion strength of the shielding layer 120 should be at least 2.5 MPa. In particular, when the housing according to the present invention is used in an environment with a large temperature change (for example, a battery housing of an electric vehicle) The adhesion strength of the layer 120 is preferably 6.0 MPa or more. On the other hand, the shielding layer 120 should have a shielding ability higher than a certain level.

Hereinafter, the shielding ability of the shielding layer 120 will be described. The shielding layer 120 to be described below has a shielding ability of 80 dB or more at 30 MHz to 1.5 GHz, but is not limited thereto.

There are three major factors that affect the shielding ability. Specifically, the material is the surface resistance of the shielding layer 120, the thickness of the shielding layer 120, and the material forming the shielding layer 120. Hereinafter, the above-mentioned three factors will be described in detail.

First, the sheet resistance of the shielding layer 120 should be 0.01 Ω / sq or less. The sheet resistance refers to the electrical conductivity of the shielding layer 120. As the electrical conductivity of the shielding layer 120 increases, shielding ability of the shielding layer 120 increases, so that the sheet resistance of the shielding layer 120 is preferably low. In order for the shielding layer 120 to have a shielding ability of 80 dB or more, the sheet resistance of the shielding layer 120 should be 0.01? / Sq or less.

Here, since the sheet resistance of the shielding layer 120 increases as the porosity of the shielding layer 120 increases, the porosity is preferably 5% or less.

Second, the thickness of the shielding layer 120 should be 5 占 퐉 or more. As the thickness of the shielding layer 120 increases, the shielding ability 120 increases. The minimum thickness for the shielding layer 120 to have a shielding ability of 80 dB or more is 5 탆. However, the thickness of the shielding layer 120 is preferably 50 mu m or more. It is not easy to control the metal or alloy layer to a thickness of less than 50 mu m due to the characteristic of the melt injection method. Therefore, when the shielding layer 120 is formed to be less than 50 mu m, the shielding layer 120 can be formed non-uniformly.

On the other hand, as the thickness of the shielding layer 120 is thicker, shielding ability becomes better, but the weight of the housing increases. When the thickness of the shielding layer 120 exceeds 300 탆, the shielding ability is not greatly improved even if the thickness of the shielding layer 120 is increased. Therefore, it is preferable that the thickness of the shielding layer 120 is 300 mu m or less.

Third, the electromagnetic shielding capability may be different depending on the type of metal or alloy. In particular, the magnetic shielding shielding ability varies greatly depending on the type of metal or alloy. The shielding layer 120 may be made of one of Fe, Co, Ni, Fe-Co, Fe-Ni, Fe-Si, and Co-Ni to improve the magnetic shielding ability.

As described above, the sheet resistance of the shielding layer 120 should be 0.01? / Sq and the thickness should be 5 占 퐉 or more. The shielding layer 120 may be formed of any one of Fe, Co, Ni, Fe-Co, Fe-Ni, Fe-Si, and Co- .

In one embodiment, a shielding layer made of Zn metal was formed on the surface of reinforced plastic made of PA66 and 30 wt.% Of glass fiber, and the electromagnetic shielding ability was measured according to ASTM D4935 standard. A cross-sectional photograph of the housing according to the above embodiment is shown in FIG. 6, and the measurement result of the electromagnetic wave shielding ability is shown in FIG.

Referring to FIG. 6, the thickness of the zinc metal layer (white) is about 100 μm, and it can be confirmed that the zinc metal layer is solidified while the zinc metal penetrates the plastic surface. On the other hand, the sheet resistance of the zinc metal layer was measured to be 0.002? / Sq or less and the average adhesion strength was 6.0 MPa.

Referring to FIG. 7, it can be seen that the housing according to the embodiment has a shielding ability of 80 dB or more at 30 MHz to 1.5 GHz.

According to the above-described embodiment, it is confirmed that the shielding layer 120 included in the housing according to the present invention has a high adhesive strength and excellent shielding ability.

In the foregoing, the housing according to the present invention has been described. Modifications of the housing according to the present invention will be described below.

The shielding layer 120 included in the housing according to the present invention may be formed of a plurality of layers. 3, the adhesion strength and shielding ability of the shielding layer 120 may vary depending on the material forming the shielding layer 120. As shown in FIG. For example, the adhesion strength to plastics is high, but the shielding ability may be low, and the adhesion strength to plastic may be low, but the shielding layer may have a high material. When the shielding layer 120 is formed of layers of different materials, only the advantages of each of the plurality of materials can be utilized.

8 is a cross-sectional view of a housing including a shielding layer 120 formed of a plurality of layers.

Referring to FIG. 8, the first layer 121 may be laminated on the body surface and the second layer 122 may be laminated on the first layer 121. However, the number of layers constituting the shielding layer 120 is not limited to two in the housing 100 described with reference to FIG. The shielding layer 120 may further comprise at least one layer deposited on the second layer 122.

The first layer 121 is a layer in contact with the body 110 and should have a high adhesion strength. The first layer 121 is solidified into a state 121a penetrating the surface of the body 110 like the shielding layer 120 described with reference to FIG. On the other hand, since the second layer 122 is laminated on the first layer 121, the adhesion to the first layer 121 should be high.

As described above, the first and second layers 121 and 122 have different physical properties. Hereinafter, the physical properties of the first and second layers 121 and 122 will be described for convenience of explanation.

First, the adhesion strength of each of the first and second layers 121 and 122 to plastic will be described. The first layer 121 may be a material having a higher adhesion strength to plastic than the second layer 122. Since the first layer 121 is in contact with the body 110, the adhesive force between the first layer 121 and the plastic forming the body 110 must be high. On the other hand, since the second layer 122 is not a layer that is in substantial contact with the body 110, the adhesion of the second layer 1220 to the plastic need not be high.

Next, the electrical conductivity of the second layer 122 may be higher than that of the metal or alloy of the first layer 121. When the first layer 121 is made of a material having a high adhesion strength to plastic, the advantage of the first layer 121 having a high adhesion strength to plastic and the strength of the second layer 122 having a good shielding ability 122 The benefits can be saved at the same time.

Next, the adhesion strength between the first and second layers 121 and 122 will be described. When the shielding layer 120 is formed of a plurality of layers, delamination may be a problem. In order to solve this problem, the melting point of the material forming the second layer 122 may be higher than the melting point of the material forming the first layer 121. The second layer 122 is melted and spun on the surface of the first layer 121. If the melting point of the material to be radiated is higher than that of the first layer 121, . Accordingly, the materials constituting each of the first layer 121 and the second layer 122 can be mixed with each other in a molten state to form an alloy.

According to the above description, a mixed material of the first and second layers 121 and 122 may be formed between the first and second layers 121 and 122. The alloy layer formed between the first and second layers 121 and 122 can increase the bond strength between the first and second layers 121 and 122.

Next, thicknesses of the first and second layers 121 and 122 will be described. In order for the shielding layer 120 to have a shielding ability of 80 dB or more, the sum of the thicknesses of the first and second layers 121 and 122 should be 5 탆 or more.

Here, when the second layer 122 is higher in electric conductivity than the metal or the alloy of the first layer 121 than the metal or the alloy, the thickness of the first layer 121 is higher than that of the second layer 122 Is preferably smaller than the thickness. More specifically, the present invention maximizes the thickness of the second layer 122 and maximizes the shielding ability of the shielding layer 120 by minimizing the thickness of the first layer 121, securing only the adhesion to the plastic surface, can do.

Finally, the porosity of the first and second layers 121 and 122 will be described. When the adhesive force of the material of the first layer 121 to the plastic is high, the porosity of the first layer 121 is not necessarily 5% or less. Since the first layer 121 is covered with the second layer 122, it is less likely to be oxidized even if the porosity exceeds 5%, and since the main shielding function is not performed, even if the sheet resistance is high, It does not greatly affect shielding ability.

However, since the second layer 122 is exposed to the outside when there is no other layer covering the second layer 122, there is a risk of oxidation, and the shielding layer 121, which is superior to the first layer 121 for securing the adhesion to plastic, Because it has ability, porosity should be low. That is, the porosity of the second layer 122 should be lower than that of the first layer 121.

As described above, when the shielding layer 120 is composed of a plurality of layers, it is possible to take advantage of each of the plurality of layers.

In one embodiment, a first layer made of Zn metal and a second layer made of Al metal are formed on the reinforced plastic surface made of PA66 and 30 wt.% Of glass fiber, and the electromagnetic wave shielding ability is measured according to ASTM D4935 standard Respectively. A cross-sectional photograph of the housing according to the above embodiment is shown in FIG. 9, and the measurement result of the electromagnetic shielding ability is shown in FIG.

Referring to FIG. 9, the thickness of the first layer was 130 to 170 占 퐉, and the thickness of the second layer was 60 to 100 占 퐉. It can be confirmed that solidified with the zinc metal penetrating the plastic surface. On the other hand, the sheet resistance of the shielding layer was measured to be 0.001? / Sq or less, and the average adhesion strength was 6.0 MPa.

Referring to FIG. 10, it can be seen that the housing according to the embodiment has a shielding ability of 80 dB or more at 30 MHz to 1.5 GHz.

As described above, even when the shielding layer 120 is formed of a plurality of layers, the shielding layer 120 can have excellent adhesion strength and shielding ability.

On the other hand, it is possible to improve the magnetic shielding ability of the housing according to the present invention by configuring a part of the plurality of layers with a material having a high magnetic shielding ability.

At least one of the plurality of layers constituting the shielding layer 120 may be a magnetic layer made of any one of Fe, Co, Ni, Fe-Co, Fe-Ni, Fe-Si and Co-Ni.

Meanwhile, the thickness of the magnetic layer may be 10 to 300 mu m. When the magnetic layer is formed to a thickness of less than 10 mu m, it is practically difficult to expect a magnetic shielding effect. On the other hand, when the thickness of the magnetic layer exceeds 300 탆, the weight of the housing can be excessively increased.

In the foregoing, the housing according to the present invention has been described. Hereinafter, a method of coating the shielding layer included in the housing will be described.

The present invention forms a shielding layer 120 by rapidly fusing molten metal to the surface of a plastic body 110 that has been processed into a uniform shape. At this time, a method may be utilized in which the metal powder is melted using the plasma jet as a heat source, and the molten metal is injected by using compressed air. However, the melting injection method is not limited thereto.

On the other hand, the porosity of the shielding layer 120 may vary depending on the injection speed of the molten metal. Specifically, the injection rate of the molten metal should be 300 to 500 m / s. When the injection rate of the molten metal is less than 300 m / s, the particle size of the shielding layer 120 becomes large and the porosity becomes high. On the other hand, when the jetting speed exceeds 500 m / s, no metal is deposited on the surface of the body 110 well.

On the other hand, the melt spraying method is difficult to control when the coating layer is formed to 50 탆 or less. In order to form the shielding layer 120 having a high uniformity by the melt injection method, the thickness of the shielding layer 120 should be 100 to 200 탆.

On the other hand, in order to improve the adhesion strength of the shielding layer 120, a surface treatment step for the body 110 may be performed before injecting the molten metal. Specifically, the surface treatment step may be performed in two different ways.

First, the surface treatment step may be performed by dry surface treatment. Specifically, the surface of the body 110 may be irradiated with a plasma beam or an ion beam to form a concave-convex structure on the surface of the body 110.

Also, a method of colliding particles having a size of 1 to 1000 mu m on the surface of the body 110 with the body 110 can be used. The particles colliding with the body 110 may be any one of SiC, Al2O3, cubic boron nitride (CBN), boron carbide, borcarbide (B4C), tungsten carbide (WC), titanium carbide (TiC) have. Here, the injection speed of the particles may be 100 to 500 m / s.

Second, the surface treatment step may be performed by wet surface treatment. Specifically, the surface of the body 110 can be roughened by impregnating the body 110 with an aqueous solution of NaOH, KOH, or the like.

Through the above-described surface treatment step, the adhesion strength of the shielding layer 120 can be improved.

As described above, according to the present invention, a metal or alloy coating layer can be attached to a plastic surface with high adhesion strength. Accordingly, the present invention can form a main material constituting a housing for an electronic part as a light-weight reinforced plastic, and can coat a metal or an alloy that shields the plastic surface. Since the ratio of the relatively heavy metal or alloy in the housing according to the present invention is very low, according to the present invention, it is possible to provide a housing which is lighter than the housing of the conventional electronic component and has the electromagnetic shielding function.

It will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof.

In addition, the above detailed description should not be construed in all aspects as limiting and should be considered illustrative. The scope of the present invention should be determined by rational interpretation of the appended claims, and all changes within the scope of equivalents of the present invention are included in the scope of the present invention.

Claims (16)

A housing for electromagnetic shielding,
A body made of plastic; And
And a shielding layer composed of at least one of Al, Si, V, Cr, Fe, Co, Ni, Cu, Zn, Ag and Sn,
Wherein a part of the shielding layer is formed by being solidified while being infiltrated into the plastic surface. The method according to claim 1,
Wherein the thickness of the shielding layer is 5 to 300 占 퐉. The method according to claim 1,
And the adhesive strength of the shielding layer is 2.5 MPa or more. The method according to claim 1,
Wherein the sheet resistance of the shielding layer is 0.01? / Sq or less. The method according to claim 1,
Wherein the shielding layer has a porosity of 5% or less. The method according to claim 1,
Wherein a concavity and convexity are formed in a region of the surface of the body where the shielding layer is coated. The method according to claim 1,
The shielding layer
A plurality of layers,
A first layer stacked on the body surface; And
And a second layer laminated on the first layer. 8. The method of claim 7,
The bond strength to the body surface may be,
Wherein the metal or alloy of the first layer is higher than the metal or alloy of the second layer. 8. The method of claim 7,
Wherein the electrical conductivity of the metal or alloy forming the second layer is higher than the electrical conductivity of the metal or alloy forming the first layer. 8. The method of claim 7,
And an alloy layer formed by mixing a metal or an alloy of the first and second layers is formed between the first and second layers. 8. The method of claim 7,
Wherein the melting point of the metal or alloy forming the second layer is higher than the melting point of the metal or alloy forming the first layer. 8. The method of claim 7,
Wherein the thickness of the first layer is less than the thickness of the second layer. 8. The method of claim 7,
Wherein the porosity of the first layer is greater than the porosity of the second layer. 8. The method of claim 7,
Wherein at least one of the plurality of layers is a magnetic layer made of any one of Fe, Co, Ni, Fe-Co, Fe-Ni, Fe-Si and Co-Ni. 15. The method of claim 14,
Wherein the thickness of the magnetic layer is 10 to 300 占 퐉. A method of coating an electromagnetic shielding layer on a plastic housing,
Performing a surface treatment on the body so that concavities and convexities are formed on the surface of the body made of plastic; And
And spraying a metal or alloy in a molten state composed of at least one of Al, Si, V, Cr, Fe, Co, Ni, Cu, Zn, Ag and Sn on the body surface,
Wherein the injection speed of the molten metal or alloy is 300 to 500 m / s.

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