JPH03151697A - Radio wave absorbing material - Google Patents
Radio wave absorbing materialInfo
- Publication number
- JPH03151697A JPH03151697A JP29203089A JP29203089A JPH03151697A JP H03151697 A JPH03151697 A JP H03151697A JP 29203089 A JP29203089 A JP 29203089A JP 29203089 A JP29203089 A JP 29203089A JP H03151697 A JPH03151697 A JP H03151697A
- Authority
- JP
- Japan
- Prior art keywords
- radio wave
- wave absorbing
- carbon
- carbon powder
- absorbing 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.)
- Granted
Links
- 239000011358 absorbing material Substances 0.000 title claims abstract description 15
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 39
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 16
- 229920000049 Carbon (fiber) Polymers 0.000 claims abstract description 15
- 239000004917 carbon fiber Substances 0.000 claims abstract description 15
- 239000000203 mixture Substances 0.000 claims abstract description 9
- 239000011230 binding agent Substances 0.000 claims abstract description 8
- 238000002156 mixing Methods 0.000 claims abstract description 5
- 239000000463 material Substances 0.000 abstract description 18
- 239000003610 charcoal Substances 0.000 abstract description 6
- 239000002245 particle Substances 0.000 abstract description 5
- 238000000465 moulding Methods 0.000 abstract description 3
- 239000000843 powder Substances 0.000 abstract description 3
- 229910052799 carbon Inorganic materials 0.000 description 11
- 238000010521 absorption reaction Methods 0.000 description 7
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 4
- 239000004566 building material Substances 0.000 description 4
- 241000282320 Panthera leo Species 0.000 description 3
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 3
- 239000008187 granular material Substances 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 2
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 2
- 239000005977 Ethylene Substances 0.000 description 2
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 2
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 description 2
- 239000006229 carbon black Substances 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 229920003023 plastic Polymers 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- GHMLBKRAJCXXBS-UHFFFAOYSA-N resorcinol Chemical compound OC1=CC=CC(O)=C1 GHMLBKRAJCXXBS-UHFFFAOYSA-N 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 235000013162 Cocos nucifera Nutrition 0.000 description 1
- 244000060011 Cocos nucifera Species 0.000 description 1
- 229920000877 Melamine resin Polymers 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 229920000297 Rayon Polymers 0.000 description 1
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- MTAZNLWOLGHBHU-UHFFFAOYSA-N butadiene-styrene rubber Chemical compound C=CC=C.C=CC1=CC=CC=C1 MTAZNLWOLGHBHU-UHFFFAOYSA-N 0.000 description 1
- 239000004202 carbamide Substances 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- -1 etc. Substances 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 238000010295 mobile communication Methods 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 229920002239 polyacrylonitrile Polymers 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000002964 rayon Substances 0.000 description 1
- 239000012779 reinforcing material Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野］
本発明は、優れた機械的強度と剛性を備える電波吸収材
に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a radio wave absorbing material having excellent mechanical strength and rigidity.
近年、高度情報社会の実現に向けて、移動通信分野を中
心に電波利用が急速に拡大している。また、今日のマイ
クロエレクトロニクス技術の革新的進歩に伴って多様な
電子機器が普及している。In recent years, the use of radio waves has been rapidly expanding, mainly in the mobile communications field, with the aim of realizing an advanced information society. Furthermore, with the innovative progress of today's microelectronic technology, a variety of electronic devices are becoming widespread.
このような背景のもとに、各種の無線機器、電子機器等
から副次的に発生する不要電波による電磁波障害は年々
増大の１頃向にあり、このため建物内での良好な電磁環
境（ＥＭＣ）を保持するに必要な性能の良い電波吸収材
の開発が急がれている。Against this background, electromagnetic interference caused by unnecessary radio waves generated by various wireless devices, electronic devices, etc. is increasing year by year, and for this reason, it is important to maintain a good electromagnetic environment inside buildings ( There is an urgent need to develop radio wave absorbing materials with good performance required to maintain EMC.
電波吸収材に用いられる材料は電磁エネルギーを有効に
減衰させる電気損失、磁気損失の大きな物質で構成する
ことが重要で、従来からこの要件を満たす各種のオーム
損失材料、誘電体損失材料、磁気損失材料などが開発、
提供されている。It is important that the materials used for radio wave absorbers are made of materials with large electrical and magnetic losses that effectively attenuate electromagnetic energy, and there have traditionally been various ohmic loss materials, dielectric loss materials, and magnetic loss materials that meet this requirement. Developed materials, etc.
provided.
最も代表的な電波吸収材としては、カーボンを発泡ウレ
タンのような絶縁性樹脂材料に保持させたもの、あるい
はゴムやプラスチックにカーボンを混合したものが知ら
れている。The most typical radio wave absorbing materials are those in which carbon is held in an insulating resin material such as urethane foam, or those in which carbon is mixed with rubber or plastic.
しかしながら、発泡ウレタンを保持材とするタイプのも
のは、素材自体が軟弱なために脱型・加工等の成形作業
に熟練を要し、それ自体で所望の形態を保持することが
できない欠点がある。また、ゴム、プラスチックなどを
マトリックスとするものにあっては、カーボンを均一に
分散させることに困難性を有するうえに、成形組織の強
度、耐候性が不十分で建材的に適用するができない問題
点がある。このため、組織の補強を図るために炭素繊維
のような繊維強化材を混入する方法も提案されているが
、均質な機械的強度および剛性を付与するまでには至っ
ていない。However, the type that uses foamed urethane as a holding material requires skill in molding operations such as demolding and processing because the material itself is weak, and has the disadvantage that it cannot maintain the desired shape by itself. . In addition, with materials that have a matrix of rubber, plastic, etc., it is difficult to disperse carbon uniformly, and the strength and weather resistance of the molded structure are insufficient, making it impossible to apply them as building materials. There is a point. For this reason, methods have been proposed in which fiber reinforcing materials such as carbon fibers are mixed in to strengthen the tissue, but this has not yet resulted in uniform mechanical strength and rigidity.
本発明者らは、保持材自体が誘電損失性ならびに良成形
性を備える材料について多面的に試験研究をおこなった
結果、活性炭の粉粒体がこの要件に合致することを確認
して本発明の開発に至ったものである。したがって、本
発明の目的は、優れた機械的強度および剛性を有する成
形組織と適正な電波吸収性能を備える電波吸収材を提供
するところにある。The present inventors conducted a multifaceted test and research on materials whose holding material itself has dielectric loss properties and good formability, and as a result, they confirmed that activated carbon powder and granules meet these requirements. This is what led to the development. Therefore, an object of the present invention is to provide a radio wave absorbing material having a molded structure having excellent mechanical strength and rigidity and appropriate radio wave absorption performance.
〔課題を解決するための手段〕
上記の目的を達成するための本発明による電波吸収材は
、活性炭の粉粒体にカーボン粉末および／または炭素繊
維をバインダーとともに混合した成分組成の成形体から
なることを構成上の特徴とする。[Means for Solving the Problems] The radio wave absorbing material according to the present invention for achieving the above object is composed of a molded body having a component composition in which carbon powder and/or carbon fibers are mixed with activated carbon powder and granules together with a binder. This is a structural feature.
本発明で保持母材を構成する活性炭としては、木炭、鋸
くず炭、椰子殻炭、石炭などを賦活してえられる粉粒体
で、とくに粒度１０〜１００メツシユの範囲で適宜の粒
度分布で配合したものが有効に用いられる。The activated carbon constituting the holding base material in the present invention is a powder obtained by activating charcoal, sawdust charcoal, coconut shell charcoal, coal, etc., and is particularly suitable for particle size distribution in the range of 10 to 100 mesh. A blended product can be used effectively.
活性炭の粉粒体には、カーボン粉末、炭素繊維もしくは
これらの両者をバインダーとともに混合する。カーボン
粉末としては、黒鉛、コークス等を微粉砕したもの、カ
ーボンブラック等が使用されるが、カーボンブラックを
適用する場合には導電性カーボンブラックが有効である
。また、炭素繊維はポリアクリルニトリル系、レーヨン
系あるいはピッチ系のいずれでもよく、通常、１〜３ｍ
ｍ程度に裁断したチョップとして使用に供する。For activated carbon powder, carbon powder, carbon fiber, or both are mixed together with a binder. As the carbon powder, finely pulverized graphite, coke, etc., carbon black, etc. are used, but when carbon black is used, conductive carbon black is effective. Further, the carbon fiber may be polyacrylonitrile-based, rayon-based, or pitch-based, and usually has a length of 1 to 3 m.
Use as chops cut into pieces of about m.
カーボン粉末および／または炭素繊維は、例えば酢酸ビ
ニル／エチレン系、酢酸ビニル／エチレン／アクリル系
、スチレン／塩化ビニール系、スチレン／ブタジェン系
、アクリル系、スチレン／アクリル系、ホルマリン系（
ユリア、メラミン、フェノール、レゾルシノール樹脂等
）などの樹脂バインダーと混合した状態で活性炭粉粒体
と混合されるが、導電性カーボンブラックを予め上記の
バインダー成分に懸濁させた市販のカーボンペーストを
用いた場合に特に良結果が得られる。The carbon powder and/or carbon fiber may be, for example, vinyl acetate/ethylene, vinyl acetate/ethylene/acrylic, styrene/vinyl chloride, styrene/butadiene, acrylic, styrene/acrylic, formalin (
Activated carbon powder is mixed with a resin binder such as urea, melamine, phenol, resorcinol resin, etc., but a commercially available carbon paste in which conductive carbon black is suspended in the above binder components in advance is used. Particularly good results are obtained when
これらカーボン粉末および／または炭素繊維は、活性炭
の粉粒体に対し１０〜２０ｇ／ １．の配合比となるよ
うに混合することが望ましく、この範囲を外れる場合に
は適正な電波吸収性が確保し難くなる。The amount of these carbon powders and/or carbon fibers is 10 to 20 g/1. It is desirable to mix the components so that the mixing ratio is within this range; if the ratio is outside this range, it will be difficult to ensure proper radio wave absorption.
上記のようにして活性炭の粉粒体にカーボン粉末および
／または炭素繊維をバインダーとともに混合した成分組
成を所望の模形、角錐、板状等の形状にモールド成形す
ることにより本発明の電波吸収材が形成される。The radio wave absorbing material of the present invention is produced by molding the component composition obtained by mixing activated carbon powder and/or carbon fiber together with a binder into a desired model, pyramid, plate shape, etc. as described above. is formed.
この電波吸収材は、他の建材と同様な用途に供するため
に不燃化を目的とした材料を塗布あるいは含浸させたり
、顔料による彩色を施すことも可能である。This radio wave absorbing material can be coated or impregnated with a material intended to make it nonflammable, or colored with a pigment, in order to serve the same purpose as other building materials.
本発明によれば、本来的に誘電損失特性を有する成形性
の良好な活性炭の粉粒体を保持材とし、これにカーボン
粉末および／または炭素繊維をバインダーを介して混入
した成分組成の成形体として構成されるから、常に吸収
する電波の周波数に適した電波吸収性と強度と剛性に優
れる成形体として提供することができる。そのうえ、成
分組成がカーボン主体となっているため、耐候性が良好
で建材としても好適な電波吸収材が得られる。According to the present invention, a molded product having a component composition in which a holding material is activated carbon powder and granules that inherently have dielectric loss characteristics and good moldability, and carbon powder and/or carbon fibers are mixed therein via a binder. Therefore, it is possible to provide a molded article that has excellent radio wave absorbing properties, strength, and rigidity suitable for the frequency of the radio waves that it always absorbs. Furthermore, since the component composition is mainly carbon, a radio wave absorbing material with good weather resistance and suitable as a building material can be obtained.
以下、本発明を実施例に基づいて詳細に説明する。 Hereinafter, the present invention will be explained in detail based on examples.
実施例１
活性炭粉末（粒子径５０メツシユ）に、導電性カーボン
ブラックを分散剤としたカーボンペースト〔ライオン■
製、ライオンペースト一−３１１Ｎ）をカーボン含有量
（Ｃ景）が相違するように混合し、これをモールド成形
して縦横４０ｍｍ、厚さ７ｗ１Ｉ１１の板状成形体とし
た。Example 1 Carbon paste [Lion ■] using conductive carbon black as a dispersant in activated carbon powder (particle size 50 mesh)
Lion Paste 1-311N) manufactured by Lion Paste Co., Ltd., were mixed so as to have different carbon contents (C), and the mixture was molded to form a plate-shaped molded body measuring 40 mm in length and width and 7W1I11 in thickness.
得られた各成形体の誘電率を測定し、結果を第１表に示
した。The dielectric constant of each of the molded bodies obtained was measured and the results are shown in Table 1.
なお、誘電率の測定は、試片をダイレクトテストアダプ
タに挟み、Ｑメータを用いて１０ＭＨｚ 、 ３０ＭＨ
ｚ 、５０Ｍ１（ｚの各周波数でダイレクト測定法によ
りおこない、下記（１）および（２）式で誘電率を求め
た。The dielectric constant was measured by placing the specimen between direct test adapters and using a Q meter at 10 MHz and 30 MHz.
The dielectric constant was determined using the following formulas (1) and (2).
０３：試料がある場合の共振時のＱ値
第 １ 表
εｒ ＝ ｔｘ／ ｔｏ ・・・・・・（１）ｔｏ
（口ｚ Ｑ３）Ｃ
ｔａｎ δ２
・・・・・・（２）
０□ −０３
但し、上式における記号は以下とする。03: Q value at resonance when sample is present 1st table εr = tx/ to ...... (1) to
(口zQ3)Ctanδ2・・・・・・(2) 0□−03 However, the symbols in the above formula are as follows.
εｒ ：比誘電率
ｔａｎ δ：誘電正接
ｔｘ：試料厚（ｃｍ）
ｔｏ：試料がない場合の共振時の電極間最小距離（ｃｍ
）
Ｃドインダクターのみの時の共振時のＣ値（ｐＦ）０２
：試料がない場合で電極間の距離が試料厚と同じ時の共
振時のＱ値
第１表の結果から、得られた成形体の誘電率は電波吸収
材として適正のものであり、また成形体組織は優れた機
械的強度および剛性を備えていた。εr: Relative permittivity tan δ: Dielectric loss tangent tx: Sample thickness (cm) to: Minimum distance between electrodes during resonance when there is no sample (cm)
) C value (pF) at resonance when using only a C-doped inductor 02
: Q value at resonance when there is no sample and the distance between the electrodes is the same as the sample thickness From the results in Table 1, the dielectric constant of the obtained molded body is appropriate as a radio wave absorbing material, and the molded body The body tissue had excellent mechanical strength and stiffness.
実施例２
活性炭粉末（粒子径５０メツシユ）に、実施例１と同一
のカーボンペーストおよび炭素繊維チョップ（長さ０．
７ｍｍ）をそれぞれカーボン含有量が１０ｇ＃２の配合
比となるように混合し、これをモールド成形して縦横４
０＋ｎ＋＋＋、厚さ７Ｉｎ１１１の板状体に成形した。Example 2 Activated carbon powder (particle size: 50 mesh) was added with the same carbon paste and carbon fiber chops (length: 0.5 mm) as in Example 1.
7mm) were mixed so that the carbon content was 10g #2, and this was molded into 4
It was molded into a plate-like body with a thickness of 0+n+++ and a thickness of 7 In111.
得られた成形体は高度の曲げ強さと弾性率を備えており
、その誘電率は第２表のように適正な電波吸収特性を示
した。The obtained molded body had high bending strength and elastic modulus, and its dielectric constant showed appropriate radio wave absorption characteristics as shown in Table 2.
第２表
１０ＭＨｚ ３０ＭＨｚ ５０ＭＨｚεｒ
ｔａｎδ εｒ ｔａｎδ εｒ ｔａｎδ実施例３
誘電率（εｒ）５．０、誘電損失（ｔａｎδ）１．０の
成分組成を有する活性炭／カーボンペースト混合物を第
１図に示す楔形状に成形し、この理論的電波吸収量を測
定した。その結果、第２図のような電波吸収性能に優れ
る反射損失（ｄＢ）を示した。Table 2 10MHz 30MHz 50MHzεr
tan δ εr tan δ εr tan δ Example 3 An activated carbon/carbon paste mixture having a component composition of dielectric constant (εr) 5.0 and dielectric loss (tan δ) 1.0 was molded into the wedge shape shown in FIG. The amount of radio wave absorption was measured. As a result, it showed a reflection loss (dB) with excellent radio wave absorption performance as shown in FIG.
以上のとおり、本発明に成形性のよい活性炭を保持材と
し、これにカーボン粉末および／または炭素繊維を混入
することによって適正な電波吸収性能と優れた機械的強
度ならびに剛性を具備する電波吸収材を提供することが
できるから、建材としての電波吸収壁に適用して有用性
を期待することができる。As described above, the radio wave absorbing material of the present invention has appropriate radio wave absorption performance and excellent mechanical strength and rigidity by using activated carbon with good moldability as a retaining material and mixing carbon powder and/or carbon fibers therein. Therefore, it can be expected to be useful when applied to radio wave absorbing walls as building materials.
第１図は本発明の実施例による電波吸収材の形状を示し
た斜視図、第２図は理論的電波吸収量を例示したグラフ
である。FIG. 1 is a perspective view showing the shape of a radio wave absorbing material according to an embodiment of the present invention, and FIG. 2 is a graph illustrating the theoretical amount of radio wave absorption.
Claims (2)
繊維をバインダーとともに混合した成分組成の成形体か
らなる電波吸収材。1. A radio wave absorbing material consisting of a molded body having a composition of activated carbon powder mixed with carbon powder and/or carbon fiber along with a binder.
は炭素繊維の配合比が、１０〜２０ｇ／ｌである請求項
１記載の電波吸収材。2. The radio wave absorbing material according to claim 1, wherein the blending ratio of carbon powder and/or carbon fiber to the activated carbon powder is 10 to 20 g/l.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1292030A JPH0682942B2 (en) | 1989-11-08 | 1989-11-08 | Radio wave absorber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1292030A JPH0682942B2 (en) | 1989-11-08 | 1989-11-08 | Radio wave absorber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03151697A true JPH03151697A (en) | 1991-06-27 |
| JPH0682942B2 JPH0682942B2 (en) | 1994-10-19 |
Family
ID=17776620
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1292030A Expired - Fee Related JPH0682942B2 (en) | 1989-11-08 | 1989-11-08 | Radio wave absorber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0682942B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06314894A (en) * | 1993-04-28 | 1994-11-08 | Otsuka Sci Kk | Electromagnetic wave absorber and manufacture thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60129196U (en) * | 1984-02-06 | 1985-08-30 | 塚本 健吉 | Ferra for electromagnetic wave absorbing material |
| JPS62111500A (en) * | 1985-11-08 | 1987-05-22 | 株式会社デンソー | Electromagnetic wave reflecting unit |
-
1989
- 1989-11-08 JP JP1292030A patent/JPH0682942B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60129196U (en) * | 1984-02-06 | 1985-08-30 | 塚本 健吉 | Ferra for electromagnetic wave absorbing material |
| JPS62111500A (en) * | 1985-11-08 | 1987-05-22 | 株式会社デンソー | Electromagnetic wave reflecting unit |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06314894A (en) * | 1993-04-28 | 1994-11-08 | Otsuka Sci Kk | Electromagnetic wave absorber and manufacture thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0682942B2 (en) | 1994-10-19 |
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|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |