KR20170079461A - Nano powder absorber for improving property of antenna, and method fabricating of the same - Google Patents

Nano powder absorber for improving property of antenna, and method fabricating of the same Download PDF

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Publication number
KR20170079461A
KR20170079461A KR1020150190064A KR20150190064A KR20170079461A KR 20170079461 A KR20170079461 A KR 20170079461A KR 1020150190064 A KR1020150190064 A KR 1020150190064A KR 20150190064 A KR20150190064 A KR 20150190064A KR 20170079461 A KR20170079461 A KR 20170079461A
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KR
South Korea
Prior art keywords
metal
metal structure
antenna
plate
powder
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Application number
KR1020150190064A
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Korean (ko)
Inventor
윤재원
표정석
김락원
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(주)휴켐
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Priority to KR1020150190064A priority Critical patent/KR20170079461A/en
Publication of KR20170079461A publication Critical patent/KR20170079461A/en

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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q17/00Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q17/00Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems
    • H01Q17/008Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems with a particular shape
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K9/00Screening of apparatus or components against electric or magnetic fields
    • H05K9/0073Shielding materials
    • H05K9/0081Electromagnetic shielding materials, e.g. EMI, RFI shielding

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)

Abstract

There is provided an antenna module including a nano powder absorber for reinforcing an antenna characteristic. Wherein the antenna module including the nano powder absorber for reinforcing antenna characteristics includes an antenna portion having an antenna for transmitting and receiving data and an electromagnetic wave absorber attached to the antenna portion, wherein the electromagnetic wave absorber is formed of nano powder, And blocking the noise introduced into the antenna.

Description

Technical Field [0001] The present invention relates to a nanofiber absorber for reinforcing an antenna characteristic,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nano powder absorber for reinforcing antenna characteristics and a method of manufacturing the same. More particularly, the present invention relates to a nanopowder absorber for reinforcing an antenna characteristic attached to an antenna and minimizing noise introduced into the antenna, will be.

2. Description of the Related Art Recently, various digital electronic devices such as PCs, portable terminals, portable media players and the like have been widely used. Accordingly, there is a problem that an electromagnetic wave generated in an electronic device affects another electronic device through a space, or affects another electronic device through a wire or a PCB to cause a malfunction.

Such electromagnetic disturbances are manifested in various ways ranging from malfunctions of computers to accidental incidents of factories, and furthermore, research results that have a negative impact on the human body have been announced, thus raising concerns and concern about health. In addition, in the advanced countries, the electromagnetic wave absorption and shielding technology for various electronic appliances is emerging as the core technology field of the electronic industry, while strengthening the regulations on electromagnetic interference and preparing countermeasures.

Accordingly, various techniques for electromagnetic wave absorption and shielding have been developed. For example, Korean Patent Registration No. 10-0995563 (Application No. 10-2010-0041847, filed by Inox Co., Ltd.) has been applied to an electric wave shielding electric wire which is excellent in adhesive force, heat resistance, electric conductivity and bendability, A conductive adhesive film is disclosed.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a high-reliability nano-powder absorber for reinforcing antenna characteristics.

Another object of the present invention is to provide an absorber for reinforcing an antenna characteristic capable of improving transmission and reception characteristics of an antenna.

It is another object of the present invention to provide an nano-powder absorber for reinforcing antenna characteristics with improved electromagnetic wave absorption characteristics.

The technical problem to be solved by the present invention is not limited to the above.

According to an aspect of the present invention, there is provided an antenna module including an nano powder absorber for reinforcing an antenna characteristic.

According to one embodiment, the antenna module including the nano powder absorber for reinforcing antenna characteristics includes an antenna portion having an antenna for transmitting and receiving data, and an electromagnetic wave absorber attached to the antenna portion, And blocking the noise introduced into the antenna of the antenna unit.

According to one embodiment, the electromagnetic wave absorber comprises: a base film; and first metal structures disposed on the base film, wherein the first metal structures are formed by aggregating nano metal powders, and a second metal The structures may comprise a mixed coating.

According to an aspect of the present invention, there is provided a method of manufacturing an nano powder absorber for reinforcing an antenna characteristic.

According to another embodiment of the present invention, there is provided a method of manufacturing an absorber for reinforcing an antenna characteristic, comprising the steps of: preparing a plate-like metal structure in which nano metal powders are aggregated and a spherical metal structure in which nano- A step of wetting the plate-like metal structure and the spherical metal structure with a solvent; mixing the wetted plate-like metal structure and the spherical metal structure with a binder; Thereby forming a source layer, and forming the coating layer by providing the source layer on the base film.

According to one embodiment, the step of preparing the spherical metal structure comprises the steps of preparing a metal oxide, pulverizing the metal oxide to produce a first metal powder, flocculating the first metal powder, and And reducing the aggregated first metal powder to produce a second metal powder.

According to one embodiment, preparing the spherical metal structure may include coating the second metal powder with an organic binder, and coagulating the second metal powder coated with the organic binder to form a third metal powder And the like.

According to one embodiment, the manufacturing method of the nano powder absorber for reinforcing antenna characteristics may further include performing a defoaming process of removing bubbles from the source before providing the source on the base film .

The antenna module including the nano powder absorber for reinforcing antenna characteristics according to an embodiment of the present invention includes an antenna unit having an antenna for transmitting and receiving data and an electromagnetic wave absorber attached to the antenna unit, So that the noise introduced into the antenna of the antenna unit can be blocked. Thus, the data transmission / reception characteristics of the antenna can be improved.

1 and 2 are views for explaining an antenna module including a nano powder absorber for reinforcing antenna characteristics according to an embodiment of the present invention.
3 is a flowchart for explaining a method of manufacturing an nano-powder absorber for reinforcing antenna characteristics according to an embodiment of the present invention.
4 is a view for explaining an nano powder absorber for reinforcing antenna characteristics according to an embodiment of the present invention.
FIG. 5 is an enlarged view of FIG. 4A illustrating a coating layer included in the nano powder absorber for reinforcing antenna characteristics according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the technical spirit of the present invention is not limited to the embodiments described herein but may be embodied in other forms. Rather, the embodiments disclosed herein are provided so that the disclosure can be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

In this specification, when an element is referred to as being on another element, it may be directly formed on another element, or a third element may be interposed therebetween. Further, in the drawings, the thicknesses of the films and regions are exaggerated for an effective explanation of the technical content.

Also, while the terms first, second, third, etc. in the various embodiments of the present disclosure are used to describe various components, these components should not be limited by these terms. These terms have only been used to distinguish one component from another. Thus, what is referred to as a first component in any one embodiment may be referred to as a second component in another embodiment. Each embodiment described and exemplified herein also includes its complementary embodiment. Also, in this specification, 'and / or' are used to include at least one of the front and rear components.

The singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. It is also to be understood that the terms such as " comprises "or" having "are intended to specify the presence of stated features, integers, Should not be understood to exclude the presence or addition of one or more other elements, elements, or combinations thereof. Also, in this specification, the term "connection " is used to include both indirectly connecting and directly connecting a plurality of components.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In the present specification, electromagnetic shielding means to prevent electromagnetic waves from permeating by reflecting electromagnetic waves introduced from the outside, and electromagnetic wave absorption is a phenomenon in which an electromagnetic wave is generated by an electromagnetic wave introduced from the outside and an impedance is generated by the generated magnetic flux Which means that electromagnetic waves are lost.

Further, in this specification, the metal structure includes not only a metal, but also a metal oxide, a metal nitride, a metal carbide and the like.

1 and 2 are views for explaining an antenna module including a nano powder absorber for reinforcing antenna characteristics according to an embodiment of the present invention.

1 and 2, an antenna module including an nano powder absorber for reinforcing antenna characteristics according to an embodiment of the present invention includes an antenna unit 10 and an electromagnetic wave absorber 20 covering the antenna unit 10, . ≪ / RTI >

The antenna unit 10 may include an antenna 12. According to one embodiment, the antenna 12 may be various types of antennas such as a DMB antenna, a radio antenna, and a GPS antenna. The antenna 12 according to the embodiment of the present invention is for transmitting and receiving data, and the scope of right of the present invention is not limited by the type of data transmitted and received, and the type of antenna.

In addition, the shape of the antenna 12 may be implemented in various forms other than those shown in FIGS. 1 and 2. FIG.

The electromagnetic wave absorber 20 is formed of nano powder and can block noise introduced into the antenna 12 of the antenna unit 10. 1 and 2, the electromagnetic wave absorber 20 may be attached to a surface opposite to one surface of the antenna unit 10 on which the antenna 12 is disposed. Alternatively, according to another embodiment, the electromagnetic wave absorber 20 may be attached to the one surface of the antenna unit 10 on which the antenna 12 is disposed. Alternatively, according to another embodiment, the electromagnetic wave absorber 20 may be provided in plural and attached to the one surface and the other surface of the antenna portion 10, respectively.

According to one embodiment, the electromagnetic wave absorber 20 may be attached to the antenna unit 10 using an adhesive.

The antenna module including the nano powder absorber for reinforcing antenna characteristics according to the embodiment of the present invention to which the electromagnetic wave absorber 20 is attached may be mounted in a panel of a smart phone, As shown in FIG.

As described above, when the antenna module including the nano powder absorber for reinforcing antenna characteristics according to the embodiment of the present invention is mounted on the back cover of the smart phone, a material corresponding to the back cover of the smart phone (for example, poly The electromagnetic wave absorber 20 may include the same material as the electromagnetic wave absorber 20. The electromagnetic wave absorber 20 may include an outer surface having a hue that is the same as the color of the back cover of the smartphone, and the antenna module may be attached to the back cover of the smartphone so that the outer surface is exposed.

Hereinafter, with reference to Figs. 3 to 5, the electromagnetic wave absorber 20 formed of nano powder will be described in more detail.

FIG. 3 is a flow chart for explaining a method of manufacturing an nano powder absorber for reinforcing antenna characteristics according to an embodiment of the present invention, FIG. 4 is a view for explaining a nano powder absorber for reinforcing antenna characteristics according to an embodiment of the present invention And FIG. 5 is an enlarged view of FIG. 4A illustrating a coating layer included in the nano powder absorber for reinforcing antenna characteristics according to an embodiment of the present invention.

3 to 5, a plate-like metal structure 124 and a rectangular metal structure 122 may be prepared (S110).

The plate-like metal structure 124 may be formed by aggregating nano-sized plate-like structures in a plate-like shape. In this case, the manufacturing method of the plate-shaped metal structure 124 may include preparing a metal oxide, pulverizing the metal oxide into nano-sized powder, reducing the pulverized metal oxide to produce a magnetic metal powder A step of subjecting the magnetic metal powder to a plate treatment, and a step of heat treating the plate-shaped magnetic metal powder to remove residual stress. The magnetic metal powder may be treated in a plate-like manner, and may be agglomerated together with the pores to form the porous plate-shaped metal structure 124. The ground metal oxide may have a size of 100 nm or less. As a result, the magnetic metal powder can easily be flattened at low energy.

For example, the step of pulverizing the metal oxide and the step of plate-finishing the magnetic metal powder may be performed by a mechanical grinding method, specifically, ball milling, ultrasonic milling, bead milling, Lt; RTI ID = 0.0 > attritor. ≪ / RTI > Further, for example, the pulverized metal oxide may be reduced in a hydrogen or nitrogen atmosphere, and the plate-shaped magnetic metal powder may be heat-treated at 200 to 1400 ° C.

According to one embodiment, the plate-like metal structure 124 can be manufactured using different kinds of metal oxides (e.g., nickel oxide and iron oxide), as described above. In this case, the plate-like metal structure 124 may be formed of an alloy (for example, an alloy of nickel and iron).

According to one embodiment, the step of preparing the spherical metal structure 122 comprises the steps of preparing a metal oxide, pulverizing the metal oxide to produce a first metal powder, agglomerating the first metal powder And reducing the aggregated first metal powder to produce a second metal powder. The first metal powder may have a nano size. For example, the diameter of the first metal powder may be 100 nm or less. The second metal powder may have a diameter of 5 to 10 mu m. The second metal powder may be defined as the spherical metal structure 122.

For example, the first metal powder may be aggregated using a spray drier, and the first metal powder may be reduced at 200 to 800 ° C in a H 2 N 2 or NH 3 atmosphere. The second metal powder can be produced by bonding between powders in the process of reducing the aggregated first metal powder.

Alternatively, in contrast to the foregoing, according to another embodiment, the step of preparing the first metal powder may comprise the steps of preparing the metal oxide and additives, mixing and grinding the metal oxide and the additive have. In this case, the first metal powder may include a crushed product of the metal oxide and a crushed product of the additive. The additive may be an oxide (e.g., tungsten oxide, copper oxide, copper oxide) containing the additive element (for example, tungsten, copper, nickel, molybdenum, Nickel oxide, molybdenum oxide, chromium oxide, etc.).

According to one embodiment, the step of preparing the spherical metal structure 122 may include coating the second metal powder prepared by the above-described method with an organic binder, and coating the second metal coated with the organic binder And agglomerating the powder to produce a third metal powder. In this case, the third metal powder may have a diameter of 5 to 10 μm, and the third metal powder may be defined as the spherical metal structure 122. According to one embodiment, the second metal powder coated with the organic binder may be agglomerated by a mechanical mixing method (for example, ball milling). The third metal powder has a larger size as compared with the second metal powder and can have high fluidity. Therefore, the spherical metal structure 122 can be easily handled, the manufacturing process of the electromagnetic wave absorbing composite film can be simplified, and the manufacturing cost can be reduced.

Further, after the third metal powder is produced, the third metal powder may be further subjected to heat treatment. As a result, the cohesive strength of the third metal powder can be increased.

The plate-like metal structure 124 and the spherical metal structure 122 may be mixed (S120). According to one embodiment, the plate-like metal structure 124 may be dry-mixed with the spherical metal structure 122. For example, the plate-like metal structure 124 and the spherical metal structure 122 may be dry-mixed by any one of a pressurized mixer mixing method and a spray mixing method.

The plate-like metal structure 124 and the spherical metal structure 122 may be wetted with a solvent (S130). For example, the solvent may include at least one of toluene or methyl ethyl ketone (MEK).

The source may be manufactured by mixing the wedged plate-shaped metal structure 124 and the spherical metal structure 122 with a binder (S140). For example, the ratio of the spherical metal structure 122 in the source may be 12 to 16 wt%, and the ratio of the binder may be 14 to 18 wt%. For example, the binder may be an acrylic adhesive, or a rubber-based adhesive. According to one embodiment, the plate-shaped metal structure 124 and the spherical metal structure 122, and the binder, which are wetted, may be dispersed and mixed using a Planter mixer. As a result, the shape of the plate-shaped metal structure 124 can be easily maintained without being broken or broken.

After the source is manufactured, a defoaming process may be further performed to remove bubbles from the source before providing the source on the base film.

The source may be provided on the base film 100 to form the coating layer 120 (S150). Providing the source on the base 100 may be performed by a roll-to-roll process have.

Thereafter, the electromagnetic wave-absorbing composite film including the base film 100 and the coating layer 120 may be stored in a wound state. Alternatively, the electromagnetic wave-absorbing composite film may be attached to another functional film (for example, a heat-radiating film or the like).

According to an embodiment of the present invention, the plate-like metal structure 124 and the spherical metal structure 122 may be mixed with each other to produce the source. Due to the ball bearing effect of the spherical metal structure 122 in the process of manufacturing the source using the plate-like metal structure 124 and the spherical metal structure 122, 124 are easily dispersed in the source, and the plate-like metal structure 124 can be maintained in a form that is not broken during mixing with the binder. Therefore, the plate-like metal structure 124 can be substantially uniformly distributed in the coating layer 120, thereby realizing a highly reliable electromagnetic wave absorption with a substantially uniform electromagnetic wave absorption rate and an improved electromagnetic wave absorption rate A composite film may be provided.

In addition, according to the embodiment of the present invention, as described above, the plate-like metal structure 124, the spherical metal structure 122, and the binder are dispersed and mixed in a Plantar mixer, The shape of the structure 124 may be maintained during the fabrication of the source. Therefore, the plate-shaped metal structure 124 can be dispersed intact in the coating layer 120 without substantial deformation of the shape, and the electromagnetic wave absorbing composite having improved electromagnetic wave absorption efficiency due to the laminated metal structure 124 A film may be provided.

Further, according to the embodiment of the present invention, the plate-like metal structure 124 and the spherical metal structure 122 may be wetted and then mixed with the binder so that the source can be manufactured. Unlike the above-described embodiment of the present invention, when the plate-like metal structure 124 and the spherical metal structure 122 are mixed together with the binder, they are mixed with a solvent to produce a source, or the plate- When a source is manufactured by mixing the metal structure 124 and the spherical metal structure 122 together with a binder and a solvent, a large amount of air bubbles are formed on the surfaces of the plate-shaped metal structure 124 and the spherical metal structure 122, May remain. When the coating layer 120 is formed using a source including a large amount of bubbles, the electromagnetic wave absorption characteristic may be degraded. It is also easy to uniformly disperse the plate-shaped metal structure 124 and the second metal structure 122 in the source owing to the cohesive force between the plate-like metal structure 124 and the spherical metal structure 122 I do not.

However, as described above, according to the embodiment of the present invention, after the plate-like metal structure 124 and the spherical metal structure 122 are wetted with the solvent, they are mixed with the binder, The degree of dispersion of the plate-like metal structure 124 and the spherical metal structure 122 is improved and the bubbles on the plate-shaped metal structure 124 and the sphere-shaped metal structure 122 can be easily removed . Accordingly, the filling rate of the plate-like metal structure 124 and the spherical metal structure 122 in the coating layer 120 can be increased. Accordingly, an electromagnetic wave absorbing composite film having improved electromagnetic wave absorption rate and electromagnetic wave shielding ratio and a manufacturing method thereof can be provided.

When the source is manufactured by using the plate-shaped metal structure 124 and the binder, the sphere-shaped metal structure 122 is omitted, unlike the embodiment of the present invention described above, 124 are not easily dispersed uniformly in the source, and the plate-shaped metal structure 124 may be broken during the dispersion process. Further, in order to disperse the plate-like metal structure 124 in the binder, a large amount of the binder is required to be used. Therefore, the plate-shaped metal structure 124 and the binder can be charged in a weight ratio of 7: 3 in the source. Due to the large amount of the binder in the source, the filling rate of the metal structure in the coating layer 120 may be reduced.

However, according to the embodiment of the present invention as described above, when the plate-shaped metal structure 124 and the spherical metal structure 122 are mixed with the binder after being wetted with the solvent, the spherical metal structure 122, the plate-like metal structure 124 can be uniformly dispersed in the binder without cracking.

Due to the ball bearing effect of the spherical metal structure 122, the plate-shaped metal structure 124 is smoothly flowed, and even though a small amount of the binder is used, the plate-shaped metal structure 124 can be uniformly dispersed . According to an embodiment, the ratio of the binder to 70wt% of the plate-like metal structure 124 in the source may be reduced to 14-18wt%.

Also, even if the source is manufactured using a small amount of binder, the degree of dispersion can be improved while maintaining the shape of the plate-like metal structure 124, so that the filling rate of the metal structure in the coating layer 120 is increased, A highly reliable electromagnetic wave absorption / shielding and heat radiation composite film with improved electromagnetic wave absorptivity can be provided.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the present invention is not limited to the disclosed exemplary embodiments. It will also be appreciated that many modifications and variations will be apparent to those skilled in the art without departing from the scope of the invention.

10:
12: Antenna
20: Electromagnetic wave absorber
100: base film
120: Coating layer
122: spherical metal structure
124: Plate-like metal structure

Claims (6)

An antenna unit having an antenna for transmitting and receiving data; And
And an electromagnetic wave absorber attached to the antenna unit,
Wherein the electromagnetic wave absorber comprises nano-powder, and shields noise introduced into the antenna of the antenna unit.
The method according to claim 1,
The electromagnetic wave absorber includes:
A base film;
And a coating layer formed on the base film, the first metal structures having a plate-like shape formed by agglomerating nano metal powders and the second metal structures having spherical nano metal powders aggregated. .
Preparing a plate-like metal structure in which nano metal powders are aggregated, and a spherical metal structure in which nano metal powders are aggregated;
Mixing the plate-like metal structure and the spherical metal structure;
Wetting the plate-like metal structure and the spherical metal structure in a solvent;
Mixing the wedged plate-shaped metal structure and the spherical metal structure with a binder to produce a source; And
And providing the source on the base film to form a coating layer.
The method of claim 3,
Wherein the step of preparing the spherical metal structure comprises:
Preparing a metal oxide;
Milling the metal oxide to produce a first metal powder;
Agglomerating the first metal powder; And
And reducing the aggregated first metal powder to produce a second metal powder.
5. The method of claim 4,
Wherein the step of preparing the spherical metal structure comprises:
Coating the second metal powder with an organic binder; And
And coagulating the second metal powder coated with the organic binder to produce a third metal powder.
6. The method of claim 5,
Further comprising performing a defoaming process to remove bubbles from the source before providing the source on the base film. ≪ Desc / Clms Page number 20 >
KR1020150190064A 2015-12-30 2015-12-30 Nano powder absorber for improving property of antenna, and method fabricating of the same KR20170079461A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021091264A1 (en) * 2019-11-05 2021-05-14 Samsung Electronics Co., Ltd. Grip detection method and electronic device supporting same

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021091264A1 (en) * 2019-11-05 2021-05-14 Samsung Electronics Co., Ltd. Grip detection method and electronic device supporting same
US11784395B2 (en) 2019-11-05 2023-10-10 Samsung Electronics Co., Ltd. Grip detection method and electronic device supporting same

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