JPH05136595A - Radio wave absorbent - Google Patents
Radio wave absorbentInfo
- Publication number
- JPH05136595A JPH05136595A JP29298891A JP29298891A JPH05136595A JP H05136595 A JPH05136595 A JP H05136595A JP 29298891 A JP29298891 A JP 29298891A JP 29298891 A JP29298891 A JP 29298891A JP H05136595 A JPH05136595 A JP H05136595A
- Authority
- JP
- Japan
- Prior art keywords
- radio wave
- zinc oxide
- alkali titanate
- conductive
- weight
- 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.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、電子レンジなどにおけ
る電波漏洩防止や発熱体用として、電磁エネルギーを吸
収して熱に変換する電波吸収材に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio wave absorber that absorbs electromagnetic energy and converts it into heat for preventing electric wave leakage in a microwave oven or for a heating element.
【０００２】[0002]
【従来の技術】従来の電波吸収材としては、フェライト
などの磁性材料、カーボンなどの導電材料などがある。
電波の吸収原理としては、前者は磁性損失を、後者は抵
抗損失を利用しており、これらの材料を単独で焼結ある
いは合成樹脂などの分散媒に混練して成型体として用い
られている。2. Description of the Related Art Conventional electromagnetic wave absorbers include magnetic materials such as ferrite and conductive materials such as carbon.
The former uses magnetic loss and the latter utilizes resistance loss as a principle of electromagnetic wave absorption, and these materials are used alone as a molded body by sintering or kneading them with a dispersion medium such as a synthetic resin.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら上記従来
の電波吸収材では、次のような課題があった。However, the above-mentioned conventional radio wave absorber has the following problems.
【０００４】フェライトなどの磁性材料を用いたもの
は、電波吸収帯域が狭く用途が限られるとともにこれ自
体の比重が大きく得られる電波吸収体が重くなる。ま
た、コストも高い。一方、カーボンなどの導電材料を用
いたものは、一般にフェライトに比べて電波吸収能が低
く、かつ分散媒中でカーボン粒子の導電ネットワークを
形成させる必要があるが混練り条件や酸化などの耐久劣
化を受けやすく安定な電波吸収特性を売ることが困難で
ある。The one using a magnetic material such as ferrite has a narrow radio wave absorption band and is limited in use, and its specific gravity is large, and the obtained radio wave absorber becomes heavy. Also, the cost is high. On the other hand, those using conductive materials such as carbon generally have lower radio wave absorption ability than ferrite, and it is necessary to form a conductive network of carbon particles in the dispersion medium, but kneading conditions and durability deterioration due to oxidation etc. It is difficult to sell stable electromagnetic wave absorption characteristics that are susceptible to susceptibility.
【０００５】本発明は上記課題を解決するもので、汎用
性があって、高い電波吸収能を有する新規な電波吸収材
を提供することを目的としたものである。The present invention has been made to solve the above problems, and an object of the present invention is to provide a novel electromagnetic wave absorber having versatility and high electromagnetic wave absorption ability.
【０００６】[0006]
【課題を解決するための手段】上記課題を解決するため
に、本発明の電波吸収材は、導電性チタン酸アルカリと
酸化亜鉛ウイスカと結合材とからなる。In order to solve the above problems, the electromagnetic wave absorber of the present invention comprises a conductive alkali titanate, zinc oxide whiskers and a binder.
【０００７】[0007]
【作用】本発明は上記構成によって優れた電波吸収特性
を有するが、その作用機構は未だ明確ではない。しか
し、現時点では次のように考えられる。The present invention has an excellent electromagnetic wave absorption characteristic due to the above-mentioned constitution, but its mechanism of action is not yet clear. However, at this point, the following can be considered.
【０００８】導電性チタン酸アルカリとは、高い誘電率
（低損失）のチタン酸アルカリの周囲をカーボンや金属
などの導電性材料で被覆したものである。また、酸化亜
鉛ウイスカは反磁性および半導電性材料である。そし
て、結合材のマトリックス中では導電性チタン酸アルカ
リの粒子間を酸化亜鉛ウイスカが電気的に接合する構造
となる。The conductive alkali titanate is a material in which the periphery of a high dielectric constant (low loss) alkali titanate is coated with a conductive material such as carbon or metal. Zinc oxide whiskers are also diamagnetic and semiconductive materials. Then, in the matrix of the binder, the zinc oxide whiskers are electrically joined between the particles of the conductive alkali titanate.
【０００９】一般に樹脂やゴム中にカーボンなどの導電
性材料を添加すると、その添加量とともに誘電損失（誘
電率と損失係数の積、電波吸収能のパラメーカーとな
る。）は上昇するがそのピーク値は低く、ある濃度以上
では逆に誘電損失は減少する。これは金属面では電波が
完全に反射されるが、これに近い状態になるからであ
る。よって、導電性材料だけでは実用的な電波吸収体は
得られていない。導電性チタン酸アルカリ単独では同様
である。一方、酸化亜鉛ウイスカは導電性の点で前述し
た導電性材料よりおとるため高充填をする必要がある
が、ウイスカのため困難である。Generally, when a conductive material such as carbon is added to resin or rubber, the dielectric loss (the product of the permittivity and the loss coefficient and the paramagnetic wave absorption capability) increases with the amount of addition, but its peak. The value is low, and above a certain concentration, the dielectric loss decreases. This is because the radio wave is completely reflected on the metal surface, but it is close to this. Therefore, a practical electromagnetic wave absorber has not been obtained with only a conductive material. The same applies to the conductive alkali titanate alone. On the other hand, zinc oxide whiskers have a higher filling rate than the above-mentioned conductive materials in terms of conductivity, and thus it is difficult to fill them in a high amount, but it is difficult because of whiskers.
【００１０】本発明の電波吸収体は前述した構造のもの
で、導電性チタン酸アルカリの導電性と酸化亜鉛のウイ
スカの半導電性の両者の特性を生かしたものになってい
ると考えられる。The radio wave absorber of the present invention has the above-mentioned structure, and it is considered that the characteristics of both the conductivity of conductive alkali titanate and the semiconductivity of zinc oxide whiskers are utilized.
【００１１】[0011]
【実施例】以下本発明の実施例を説明する。EXAMPLES Examples of the present invention will be described below.
【００１２】導電性チタン酸アルカリと酸化亜鉛ウイス
カを等量秤り取り、これを全体で２５重量％になるよう
にシリコンゴムに混入して電波吸収体を作製した。導波
管による吸収率測定で６０％の吸収率を得た。Equivalent amounts of conductive alkali titanate and zinc oxide whiskers were weighed and mixed in silicon rubber so that the total weight was 25% by weight to prepare a radio wave absorber. An absorptance of 60% was obtained by measuring an absorptance with a waveguide.
【００１３】比較例１導電性チタン酸アルカリだけで導
波吸収体を作製した（濃度は同上）。吸収率は３０％で
あった。COMPARATIVE EXAMPLE 1 A waveguide absorber was prepared using only conductive alkali titanate (concentration was the same as above). The absorption rate was 30%.
【００１４】比較例２酸化亜鉛ウイスカだけでは２０％
の吸収率であった（濃度は同上）。Comparative Example 2 20% with zinc oxide whiskers alone
Was the absorption rate (concentration same as above).
【００１５】上記構成において、導電性チタン酸アルカ
リと酸化亜鉛ウイスカの混合物は優れた電波吸収特性を
有することがわかる。It can be seen that in the above structure, the mixture of conductive alkali titanate and zinc oxide whiskers has excellent radio wave absorption characteristics.
【００１６】[0016]
【発明の効果】以上説明したように本発明の電波吸収体
は高い電波吸収能を有する。As described above, the radio wave absorber of the present invention has a high radio wave absorption ability.
Claims (1)
カと結合材とからなる電波吸収体。1. A radio wave absorber comprising a conductive alkali titanate, zinc oxide whiskers and a binder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29298891A JPH05136595A (en) | 1991-11-08 | 1991-11-08 | Radio wave absorbent |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29298891A JPH05136595A (en) | 1991-11-08 | 1991-11-08 | Radio wave absorbent |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05136595A true JPH05136595A (en) | 1993-06-01 |
Family
ID=17789021
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29298891A Pending JPH05136595A (en) | 1991-11-08 | 1991-11-08 | Radio wave absorbent |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05136595A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110804313A (en) * | 2019-12-09 | 2020-02-18 | 中国航空制造技术研究院 | High electromagnetic shielding rubber composition and preparation method thereof |
-
1991
- 1991-11-08 JP JP29298891A patent/JPH05136595A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110804313A (en) * | 2019-12-09 | 2020-02-18 | 中国航空制造技术研究院 | High electromagnetic shielding rubber composition and preparation method thereof |
| CN110804313B (en) * | 2019-12-09 | 2022-06-10 | 中国航空制造技术研究院 | High electromagnetic shielding rubber composition and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Ahmad et al. | Magnetic and microwave absorbing properties of magnetite–thermoplastic natural rubber nanocomposites | |
| US4012738A (en) | Combined layers in a microwave radiation absorber | |
| US4447492A (en) | Articles having an electrically conductive surface | |
| Vinayasree et al. | Flexible microwave absorbers based on barium hexaferrite, carbon black, and nitrile rubber for 2–12 GHz applications | |
| Wang | Microwave absorbing materials based on polyaniline composites: a review | |
| JPH07501658A (en) | Electromagnetic radiation susceptor material using ferromagnetic amorphous alloy particles | |
| KR920007431B1 (en) | Electric wave absorbing material | |
| Qi et al. | Interfacial polymerization preparation of polyaniline fibers/Co0. 2Ni0. 4Zn0. 4Fe2O4 urchin-like composite with superior microwave absorption performance | |
| CN106916450A (en) | A kind of electromagnetic wave absorption thermally conductive composition and electromagnetic wave absorption heat-conducting pad | |
| CN108865062B (en) | Electromagnetic wave absorbent and preparation method thereof | |
| Jani et al. | Tuning of microwave absorption properties and electromagnetic interference (EMI) shielding effectiveness of nanosize conducting black-silicone rubber composites over 8-18 GHz | |
| JPH05136595A (en) | Radio wave absorbent | |
| US4731286A (en) | Radio-wave absorptive gasket | |
| JPH03238895A (en) | Microwave-absorbing blank | |
| Thakur | Nanostructured MnFe2O4 anchored on graphene oxide and reduced graphene oxide sheets for effective regulation of microwave absorption performance | |
| Kadhim et al. | Preparation and study magnetic properties of the spinal ferrite Mg1− XZn XFe2O4 | |
| KR20070007311A (en) | Squeezable, cross-linked, grease-like electromagnetic wave absorber | |
| CN113511687A (en) | Wave-absorbing material and preparation method thereof | |
| JP2729486B2 (en) | Nickel-zinc ferrite material for radio wave absorber | |
| JPH107867A (en) | Electromagnetic wave-absorbing resin composition | |
| Singh et al. | Electromagnetic properties of Co-Zr substituted Ba-Sr ferrite-paraffin wax composite for EMC/EMI applications | |
| KR100258789B1 (en) | Board for absorbing electron wave | |
| Lee et al. | Prediction of electromagnetic properties of MnZn ferrite-silicone rubber composites in wide frequency range | |
| JPH08172292A (en) | Rubber-based radio-wave absorbing material | |
| JPS6020923B2 (en) | radio wave absorber |