JPS6053404B2 - radio wave shielding material - Google Patents
radio wave shielding materialInfo
- Publication number
- JPS6053404B2 JPS6053404B2 JP13986277A JP13986277A JPS6053404B2 JP S6053404 B2 JPS6053404 B2 JP S6053404B2 JP 13986277 A JP13986277 A JP 13986277A JP 13986277 A JP13986277 A JP 13986277A JP S6053404 B2 JPS6053404 B2 JP S6053404B2
- Authority
- JP
- Japan
- Prior art keywords
- radio wave
- wave shielding
- resin
- fibers
- shielding material
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Inorganic Insulating Materials (AREA)
- Aerials With Secondary Devices (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Description
【発明の詳細な説明】
本発明は電波遮蔽材料に関し、さらに詳しくは、たとえ
ばテレビやラジオなどの家電機器の筐体材料として好適
な電波遮蔽材料に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radio wave shielding material, and more particularly to a radio wave shielding material suitable for use as a housing material for home appliances such as televisions and radios.
電波遮蔽材料は、たとえは家電機器の筐体材料として使
用され、外部の妨害電波から電子回路を保護するととも
に、発振回路などから発生する電波が外部に漏洩するの
を防止する。上記のような電波遮蔽材料としては、従来
金属製や樹脂製のものが一般的に用いられている。Radio wave shielding materials are used, for example, as casing materials for home appliances, to protect electronic circuits from external interference radio waves and to prevent radio waves generated from oscillation circuits and the like from leaking to the outside. Conventionally, materials made of metal or resin are generally used as radio wave shielding materials as described above.
金属製の電波遮蔽材料は優れた電波遮蔽効果を有してい
るが、比重が大きく、しかも加工性、成形性、美観に劣
り、特に軽さと家具との調和が要求される家電機器の筐
体材料としては不向きであるという欠点があつた。一方
、樹脂製の電波遮蔽材料は加工や成形が容易であり、し
かも比重が小さいので、同一寸法であれば金属製のもの
よりもかなり軽いが、電波遮蔽効果が十分でなく、機械
的強度も低いという欠点があつた。Metal radio wave shielding materials have excellent radio wave shielding effects, but they have a large specific gravity and are poor in workability, formability, and aesthetics, especially for the housing of home appliances that require lightness and harmony with furniture. The drawback was that it was unsuitable as a material. On the other hand, radio wave shielding materials made of resin are easy to process and mold, and have a low specific gravity, so they are much lighter than metal materials with the same dimensions, but they do not have sufficient radio wave shielding effects and lack mechanical strength. It had the disadvantage of being low.
樹脂製の電波遮蔽材料の上記欠点を解決するために、樹
脂を繊維で補強した、いわゆる繊維強化樹脂として構成
することも可能であるが、単に樹ｎＬ−ＬムμｈＬｔ、
一゛１ムＩＬＬ−Ｐｌ讐 〜 一、１′ｉ、フ」、 レ
、一、−フ’Ｌ↓“托械的強度をいくらか高めることは
できても、電波遮蔽効果をも向上させることは困難であ
る。In order to solve the above-mentioned drawbacks of radio wave shielding materials made of resin, it is possible to construct the resin as a so-called fiber-reinforced resin in which the resin is reinforced with fibers, but it is possible to simply configure the resin with fibers.
Although it is possible to increase the mechanical strength to some extent, it is not possible to improve the radio wave shielding effect. Have difficulty.
さらに、このような電波遮蔽材料が家電機器の筐体材料
として用いられる場合には、移動性などの取り扱いの容
易さを求めてより一層軽量であることが要求される。本
発明の目的は、従来の電波遮蔽材料の上記欠点を解決し
、高い電波遮蔽効果を有するとともに軽量で機械的強度
に優れた電波遮蔽材料を提供するにある。Furthermore, when such radio wave shielding materials are used as casing materials for home appliances, they are required to be even lighter in weight for ease of handling such as mobility. An object of the present invention is to solve the above-mentioned drawbacks of conventional radio wave shielding materials and to provide a radio wave shielding material that has a high radio wave shielding effect, is lightweight, and has excellent mechanical strength.
本発明の上記目的は、母材となる発泡した樹脂が導電性
繊維で補強されており、かつ前記樹脂の気泡率は（３０
〜８０）％であり、さらに前記樹脂に対する前記導電性
繊維の体積比率は（８０〜１２０）％であることを特徴
とする電波遮蔽材料によつて達成される。The above-mentioned object of the present invention is that a foamed resin serving as a base material is reinforced with conductive fibers, and the resin has a pore ratio of (30
This is achieved by a radio wave shielding material characterized in that the volume ratio of the conductive fibers to the resin is (80 to 120)%.
次に、本発明の電波遮蔽材料をその一実施例に基づいて
図面を用いて説明する。Next, the radio wave shielding material of the present invention will be explained based on one embodiment thereof using the drawings.
図面は、本発明の電波遮蔽材料の一実施例を示・す概略
斜視図であり、電波遮蔽材料は包括的に符号１で示され
ている。The drawing is a schematic perspective view showing one embodiment of the radio wave shielding material of the present invention, and the radio wave shielding material is generally designated by the reference numeral 1.
２は母材となる板状の発泡した樹脂であり、４は樹脂２
中に一方向に引きそろえた状態で互いに接触するように
配置されている導電性繊維である。2 is a plate-shaped foamed resin that serves as the base material, and 4 is the resin 2.
Conductive fibers are arranged in such a way that they are aligned in one direction and in contact with each other.
３は樹脂２が発泡してでき・た気泡であり、この気泡３
は互いに独立していて連結しておらず、いわゆる独立発
泡の状態を呈している。3 is a bubble formed by foaming of resin 2, and this bubble 3
are independent from each other and are not connected, exhibiting a state of so-called independent foaming.
導電性繊維４は樹脂２に導電性を付与して電波遮蔽効果
を向上させるとともに、これの補強材としても作用し、
電波遮蔽材料としての機械フ的強度を向上させる。上記
実施例において、母材となる樹脂としてはエポキシ樹脂
、不飽和ポリエステル樹脂、フェノール樹脂、ポリイミ
ド樹脂などの熱硬化性樹脂やポリアミド樹脂やポリエチ
レン樹脂、ポリプロピレン樹脂、ポリスチレン樹脂、Ａ
ＢＳ樹脂（アクリルニトリル●ブタジエン●スチレン樹
脂）、ポリ塩化ビニル樹脂などの熱可塑性樹脂が使用さ
れる。The conductive fibers 4 impart conductivity to the resin 2 to improve the radio wave shielding effect, and also act as a reinforcing material for the resin 2.
Improves mechanical strength as a radio wave shielding material. In the above examples, the base material resins include thermosetting resins such as epoxy resins, unsaturated polyester resins, phenol resins, and polyimide resins, polyamide resins, polyethylene resins, polypropylene resins, polystyrene resins, and A.
Thermoplastic resins such as BS resin (acrylonitrile/butadiene/styrene resin) and polyvinyl chloride resin are used.
上記樹脂は、通常の発泡剤を用いて発泡される。The resin is foamed using conventional foaming agents.
たとえば、エポキシ樹脂には発泡剤としてアゾジカルボ
ンアミドが用いられる。上記発泡は、電波遮蔽材料とし
ての機械的強度を維持することができるように、独立発
泡であるのが好ましい。For example, azodicarbonamide is used as a blowing agent in epoxy resins. The foam is preferably a closed foam so that the mechanical strength as a radio wave shielding material can be maintained.
そして、その気泡率〔（全体積一樹脂の体積）×１００
／全体積〕は（３０〜８０）％の範囲である必要がある
。気泡率が３０％未満であると、通常の繊維強化樹脂と
ほとんど変わらないほど重くなる。また、８０％を越え
ると、機械的強度が低下するばかりでなく、導電性繊維
同志の接触が保てなくなり、高い電波遮蔽効果を得るこ
とができなくなる。導電性繊維としては、特別の処理を
施さなくてもそれ自身が導電性を有し、かつ高強度、高
弾性であるために樹脂の補強効果が大きく、しかも比重
が小さいという優れた特長を有する炭素繊維が特に好ま
しく用いられる。Then, the bubble rate [(total volume - volume of resin) x 100
/total volume] must be in the range of (30 to 80)%. When the cell ratio is less than 30%, the weight becomes almost the same as that of ordinary fiber-reinforced resin. Moreover, if it exceeds 80%, not only the mechanical strength will decrease, but also the contact between the conductive fibers will not be maintained, making it impossible to obtain a high radio wave shielding effect. As a conductive fiber, it has the excellent characteristics of being conductive on its own without special treatment, having high strength and high elasticity, which has a large reinforcing effect on resin, and having a low specific gravity. Carbon fiber is particularly preferably used.
しかしながら、金や銀、銅、ニッケル、アルミニウム、
鉄などの金属繊維を用いることもてきるし、それ自身は
全く導電性を有しないか、あるいはほとんど有しないガ
ラス繊維、シリコーンカーバイド繊維、ボロン繊．維、
有機高弾性繊維、ポリアミド繊維やポリエステル繊維な
どの合成繊維に金、銀、銅、ニッケル、アルミニウムな
どの金属をメッキ、溶射、蒸着などして導電性を付与し
た繊維を用いることもできる。上記のような導電性繊維
は、数ミクロンから数十ミクロンの外径を有する。However, gold, silver, copper, nickel, aluminum,
It is possible to use metal fibers such as iron, and glass fibers, silicone carbide fibers, and boron fibers, which themselves have no or little electrical conductivity. I,
It is also possible to use fibers obtained by plating, thermal spraying, vapor depositing, etc. metals such as gold, silver, copper, nickel, and aluminum on synthetic fibers such as organic high-elastic fibers, polyamide fibers, and polyester fibers to impart conductivity. The conductive fibers described above have an outer diameter of several microns to several tens of microns.
そして、導電性繊維は樹脂中に分散した短繊維の形態で
用いることもできる。しかしながら、樹脂の補強効果が
大きいこと、および木材様の感触をも良好に具現するこ
・とができることから、上記実施例のように一方向に引
きそろえた長繊維の形態で用いるのが好ましい。母材と
なる樹脂に対する導電性繊維の体積比率は、（８０〜１
２０）％の範囲である必要がある。The conductive fibers can also be used in the form of short fibers dispersed in a resin. However, since the reinforcing effect of the resin is large and the feel of wood can be achieved satisfactorily, it is preferable to use the resin in the form of long fibers aligned in one direction as in the above example. The volume ratio of the conductive fiber to the resin serving as the base material is (80 to 1
20)%.
この比率が８０％未満であると、樹脂の補強効果が得ら
れなくなつて電波遮蔽材料としての機械的強度を維持で
きなくなり、所望の電波遮蔽効果も得られなくなる。１
２０％を越えると、樹脂が発泡した際に導電性繊維同志
の接触を保てなくなり、所望の電波遮蔽効果を得ること
ができなくなるばかりでなく機械的強度も低下する。If this ratio is less than 80%, the reinforcing effect of the resin cannot be obtained, the mechanical strength as a radio wave shielding material cannot be maintained, and the desired radio wave shielding effect cannot be obtained. 1
If it exceeds 20%, the conductive fibers will not be able to maintain contact with each other when the resin is foamed, and not only will it be impossible to obtain the desired radio wave shielding effect, but the mechanical strength will also decrease.
本発明の電波遮蔽材料は、たとえば次のようにＪして作
られる。すなわち、未硬化の熱硬化性樹脂中にその硬化
温度に近い分解温度を有する発泡剤を混入してプリプレ
グシートを作り、これを板状に加熱加圧成形する際に樹
脂を発泡させ、硬化させる。以上説明したように、本発
明の電波遮蔽材料は、母材となる（３０〜８０）％の気
泡率を有するように発泡した樹脂が、樹脂に対する体積
比率が（８０〜１２０）％である導電性繊維で補強され
ている。The radio wave shielding material of the present invention is made, for example, as follows. That is, a prepreg sheet is made by mixing a foaming agent with a decomposition temperature close to the curing temperature of the uncured thermosetting resin, and when this is heated and pressure molded into a plate shape, the resin is foamed and cured. . As explained above, in the radio wave shielding material of the present invention, the base material, which is a resin foamed to have a cell ratio of (30 to 80)%, is a conductive material whose volume ratio to the resin is (80 to 120)%. reinforced with synthetic fibers.
そのため、高い電波遮蔽効果を有するとともに、軽量で
機械的強度に優れ、特に軽さと家具類との調和が要求さ
れる家電機器の筐体材料として好適である。上記電波遮
蔽効果は材料内部の導電性により得られるものであるか
ら、低周波域では反射による遮蔽効果が、また高周波域
では吸収に遮蔽効果が大きくなり、結局低周波帯（ＬＦ
帯）からミリ波帯に至る広い周波数帯域で高い電波遮蔽
効果を得ることができる。Therefore, it has a high radio wave shielding effect, is lightweight and has excellent mechanical strength, and is particularly suitable as a housing material for home appliances that require lightness and harmony with furniture. The radio wave shielding effect described above is obtained by the conductivity inside the material, so in the low frequency range, the shielding effect is due to reflection, and in the high frequency range, the shielding effect is large due to absorption, and eventually the low frequency band (LF
It is possible to obtain high radio wave shielding effects in a wide frequency band ranging from the millimeter wave band to the millimeter wave band.
たとえば、エポキシ樹脂をアゾジカルボンアミドで気泡
率５０％に独立発泡させ、炭素繊維の長繊維に対する体
積比率１００％で用いた図面で示すようなものは、エポ
キシ樹脂の板状の厚みが５ｗｎの場合で、マイクロ波域
から高周波域（ＨＦ帯）においては４０デシベル以上の
電波遮蔽効果が認められる。さらに、電波遮蔽材料とし
ての比重を小さくできることにより、厚みを少々増大さ
せてもそれほどの重量増加にはならないから、軽量性を
損わずに電波遮蔽効果と機械的強度をよソー層増大させ
ることができる。For example, if the epoxy resin is independently foamed with azodicarbonamide to a cell ratio of 50% and the volume ratio to the long carbon fibers is 100%, as shown in the drawing, the thickness of the epoxy resin plate is 5wn. In the microwave range to the high frequency range (HF band), a radio wave shielding effect of 40 decibels or more is observed. Furthermore, since the specific gravity of the radio wave shielding material can be reduced, even if the thickness is slightly increased, the weight will not increase significantly, so the radio wave shielding effect and mechanical strength can be increased without sacrificing light weight. I can do it.
さらにまた、導電性繊維を長繊維とし、これを一方向に
引きそろえて用いた場合には、木材用の感触を良好に具
現することができるようになり、木材を主流とする家具
類との調和が図れる。Furthermore, if the conductive fibers are made into long fibers and are aligned in one direction, it will be possible to embody the feel of wood well, and it will be compatible with furniture that is mainly made of wood. Harmony can be achieved.
図面は、本発明の電波遮蔽材料の一実施例を示す概略斜
視図である。
１：電波遮蔽材料、２：発泡した樹脂、３：気泡、４：
導電性繊維。The drawing is a schematic perspective view showing one embodiment of the radio wave shielding material of the present invention. 1: Radio wave shielding material, 2: Foamed resin, 3: Air bubbles, 4:
conductive fiber.
Claims (1)
おり、かつ前記樹脂の気泡率は（３０〜８０）％であり
、さらに前記樹脂に対する前記導電性繊維の体積比率は
（８０〜１２０）％であることを特徴とする電波遮蔽材
料。1. A foamed resin serving as a base material is reinforced with conductive fibers, and the cell rate of the resin is (30 to 80)%, and the volume ratio of the conductive fibers to the resin is (80 to 120%). )% radio wave shielding material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13986277A JPS6053404B2 (en) | 1977-11-24 | 1977-11-24 | radio wave shielding material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13986277A JPS6053404B2 (en) | 1977-11-24 | 1977-11-24 | radio wave shielding material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5473300A JPS5473300A (en) | 1979-06-12 |
| JPS6053404B2 true JPS6053404B2 (en) | 1985-11-26 |
Family
ID=15255264
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13986277A Expired JPS6053404B2 (en) | 1977-11-24 | 1977-11-24 | radio wave shielding material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6053404B2 (en) |
Families Citing this family (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5634449A (en) * | 1979-08-30 | 1981-04-06 | Mitsubishi Rayon Co | Electromagnetic shielding material |
| JPS57157600A (en) * | 1981-03-25 | 1982-09-29 | Fujita Corp | Electromagnetic shield structure |
| JPS586200A (en) * | 1981-07-02 | 1983-01-13 | 防衛庁技術研究本部長 | Radio wave absorber |
| JPS5846484U (en) * | 1981-09-22 | 1983-03-29 | 株式会社デンソー | Equipment equipped with electronic control equipment |
| JPS5853898A (en) * | 1981-09-25 | 1983-03-30 | 株式会社コバヤシ | Sealed case |
| JPS5849498U (en) * | 1981-09-28 | 1983-04-04 | ティーディーケイ株式会社 | radio wave reflector |
| JPS5871028A (en) * | 1981-10-21 | 1983-04-27 | Yoshio Kawabata | Thread cutting device for nut |
| JPS5878499A (en) * | 1981-11-05 | 1983-05-12 | アイシン精機株式会社 | Resin material for shielding electromagnetic wave |
| JPS5895898A (en) * | 1981-12-01 | 1983-06-07 | スタ−ライト工業株式会社 | Plastic housing with electromagnetic shielding characteristic |
| JPS5895899A (en) * | 1981-12-02 | 1983-06-07 | スタ−ライト工業株式会社 | Plastic housing with electromagnetic shielding characteristic |
| JPS58169997A (en) * | 1982-03-31 | 1983-10-06 | 日本カ−ボン株式会社 | Radio wave absorber |
| JPS58162695U (en) * | 1982-04-22 | 1983-10-29 | 大和紡績株式会社 | Molded electromagnetic wave absorbing material |
| JPS58188190A (en) * | 1982-04-27 | 1983-11-02 | 日本電気株式会社 | Method of producing radio wave absorber |
| JPS58210696A (en) * | 1982-06-02 | 1983-12-07 | ティーディーケイ株式会社 | Radio wave absorber |
| JPS58193699U (en) * | 1982-06-19 | 1983-12-23 | 学校法人 東海大学 | Radio wave absorber with breathable structure |
| JPS5923595A (en) * | 1982-07-30 | 1984-02-07 | 東芝ケミカル株式会社 | Electromagnetic shielding material |
| JPS5944897A (en) * | 1982-09-06 | 1984-03-13 | 藤森工業株式会社 | Conductive molded product and its manufacturing method |
| JPS59155198A (en) * | 1983-02-23 | 1984-09-04 | コマニ−株式会社 | Radio wave shielding room |
| JPS59175799A (en) * | 1983-03-25 | 1984-10-04 | 東邦レーヨン株式会社 | Composition for forming electromagnetic wave shielding material |
| JPS59215799A (en) * | 1983-05-24 | 1984-12-05 | 宗和化学株式会社 | Electromagnetic shield material |
| JPH023678Y2 (en) * | 1984-10-31 | 1990-01-29 | ||
| JPH0632424B2 (en) * | 1986-10-24 | 1994-04-27 | 平岡織染株式会社 | Electromagnetic wave shielding amorphous metal thin film laminated sheet |
| JPS63168093A (en) * | 1986-12-29 | 1988-07-12 | 日本電気株式会社 | Wave absorber |
-
1977
- 1977-11-24 JP JP13986277A patent/JPS6053404B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5473300A (en) | 1979-06-12 |
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