JPH0282600A - Manufacture of electromagnetic wave absorbing substrate - Google Patents
Manufacture of electromagnetic wave absorbing substrateInfo
- Publication number
- JPH0282600A JPH0282600A JP23547388A JP23547388A JPH0282600A JP H0282600 A JPH0282600 A JP H0282600A JP 23547388 A JP23547388 A JP 23547388A JP 23547388 A JP23547388 A JP 23547388A JP H0282600 A JPH0282600 A JP H0282600A
- Authority
- JP
- Japan
- Prior art keywords
- wave absorbing
- plastic layer
- thin plate
- electromagnetic wave
- radio wave
- 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
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 239000000758 substrate Substances 0.000 title claims 2
- 239000004033 plastic Substances 0.000 claims abstract description 27
- 229920003023 plastic Polymers 0.000 claims abstract description 27
- 238000010521 absorption reaction Methods 0.000 claims description 13
- 239000002023 wood Substances 0.000 claims 1
- 239000006260 foam Substances 0.000 abstract description 7
- 238000000034 method Methods 0.000 abstract description 6
- 239000004020 conductor Substances 0.000 abstract description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 abstract description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 4
- 239000000853 adhesive Substances 0.000 abstract description 4
- 230000001070 adhesive effect Effects 0.000 abstract description 4
- 229910052802 copper Inorganic materials 0.000 abstract description 4
- 239000010949 copper Substances 0.000 abstract description 4
- 229920001971 elastomer Polymers 0.000 abstract description 3
- 229910052751 metal Inorganic materials 0.000 abstract description 3
- 239000002184 metal Substances 0.000 abstract description 3
- 239000004698 Polyethylene Substances 0.000 abstract description 2
- 230000015572 biosynthetic process Effects 0.000 abstract description 2
- 229910052742 iron Inorganic materials 0.000 abstract description 2
- -1 polyethylene Polymers 0.000 abstract description 2
- 229920000573 polyethylene Polymers 0.000 abstract description 2
- 238000004080 punching Methods 0.000 abstract 1
- 239000000463 material Substances 0.000 description 32
- 229910000859 α-Fe Inorganic materials 0.000 description 10
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 8
- 239000006096 absorbing agent Substances 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 238000005187 foaming Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 239000011231 conductive filler Substances 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000004604 Blowing Agent Substances 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 238000001746 injection moulding Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 229920002803 thermoplastic polyurethane Polymers 0.000 description 1
- 239000013585 weight reducing agent Substances 0.000 description 1
Landscapes
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
- Aerials With Secondary Devices (AREA)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
本発明は、電波暗室の構築等に使用される電波吸収基材
の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing a radio wave absorbing base material used for constructing an anechoic chamber, etc.
〈従来技術〉
電波吸収基材は、入射された電波を吸収し、消失させる
ものであり、広い帯域の周波数を吸収するＷ形電波吸収
基材にあっては、電波暗室の様に、アンテナ等の特性を
調べるために、外部からの電波を遮断して無響空間を構
成するための構造材として利用される。また、特定の周
波数のみを吸収するＮ形電波吸収基材にあっては、建物
によるＴＶ電波の反射防止等に利用され、いずれも広い
用途を有する。<Prior art> A radio wave absorbing base material absorbs and eliminates incident radio waves.W-shaped radio wave absorbing base materials that absorb a wide range of frequencies are used for antennas, etc., such as in radio anechoic chambers. It is used as a structural material to create an anechoic space by blocking radio waves from outside in order to investigate the characteristics of Furthermore, N-type radio wave absorbing base materials that absorb only specific frequencies are used to prevent the reflection of TV radio waves from buildings, and both have a wide range of uses.
これらの電波吸収基材は、入射された電波に、導電損ま
たは磁性損を生じさせて、光エネルギーを熱エネルギー
に変換することにより、前記吸収能を達成するのであっ
て、導電損を生じさせる電波吸収基材としてカーボンを
成形基材に混合したものがあり、また誘電損を生じさせ
るものとしてフェライト等の粉末を成形基材に混合した
もの等がある。These radio wave absorbing base materials achieve the above-mentioned absorption ability by causing conductive loss or magnetic loss in the incident radio waves and converting optical energy into thermal energy, and they generate conductive loss. There are radio wave absorbing base materials in which carbon is mixed into a molded base material, and materials that cause dielectric loss include those in which powder such as ferrite is mixed in a molded base material.
ところで、フェライトは磁性損失を生じて、伝播を吸収
するものとして知られているが、フェライト板を用いて
、電波吸収基材を構成するためには、フェライト板は極
薄状であるため、電波暗室等の構築を可能とする適性厚
と、所要保持強度を生じさせる必要がある。また、取り
扱いを容易とし、用途を拡大し得るためには軽量である
ことも望ましい。By the way, ferrite is known to generate magnetic loss and absorb propagation, but in order to use a ferrite plate to construct a radio wave absorbing base material, the ferrite plate is extremely thin, so it is difficult to absorb radio waves. It is necessary to create an appropriate thickness and required holding strength to enable the construction of a dark room or the like. It is also desirable that the device be lightweight in order to facilitate handling and expand the range of uses.
本発明は、かかる課題を達成し得るフエライト板等−の
電磁吸収薄板を用いた電波吸収基材の製造方法の提供を
目的とするものである。An object of the present invention is to provide a method for manufacturing a radio wave absorbing base material using an electromagnetic absorbing thin plate such as a ferrite plate, which can achieve the above-mentioned problems.
〈課題を解決するための手段〉
本考案は、電磁吸収薄板上に、有孔導電層を介して、発
泡プラスチック層を所定厚に成形し、更に成形された発
泡プラスチック層の外面に、導体板を接合してなること
を特徴とする電波吸収基材の製造方法に関する。<Means for Solving the Problems> The present invention involves forming a foamed plastic layer to a predetermined thickness on an electromagnetic absorbing thin plate through a perforated conductive layer, and then forming a conductive plate on the outer surface of the formed foamed plastic layer. The present invention relates to a method for manufacturing a radio wave absorbing base material, characterized in that it is formed by bonding.
く作用〉
電磁吸収薄板上に、有孔導電層を介して、発泡プラスチ
ック層を成形するため、該発泡プラスチック層が、導電
層の孔部を介して、電磁吸収薄板に接合する。即ち、プ
ラスチック層は、保持材としての役割と共に、接着剤の
役割も同時的に生ずる。Function> In order to mold the foamed plastic layer on the electromagnetic absorption thin plate through the perforated conductive layer, the foamed plastic layer is bonded to the electromagnetic absorption thin plate through the holes in the conductive layer. That is, the plastic layer plays the role of an adhesive as well as a holding material.
〈実施例〉
本発明に係る電波吸収基材ｌの製造方法の一例を第１図
に従って説明する。<Example> An example of a method for manufacturing the radio wave absorbing base material 1 according to the present invention will be described with reference to FIG.
２は、酸化物磁性材料であηフェライト板からなる電磁
吸収薄板であって、０，１〜１ＩＩＩＩＩＩｔの極薄状
からなる。Reference numeral 2 denotes an electromagnetic absorption thin plate made of an η ferrite plate made of an oxide magnetic material, and is extremely thin with a thickness of 0.1 to 1IIIIIIt.
この電磁吸収薄板２の上面には、パンチングメタル、金
網等から成る有孔導電層３が乗載され、さらに間隔を置
いて内面にポリエチレン等の離型層４が形成された型板
５が配設され、該間隔内にウレタン樹脂と、炭酸ソーダ
、炭酸カルシウム等の発泡剤との二液が供給される。こ
れにより、二液が反応して、発泡し、膨張する（第１図
イ）。A perforated conductive layer 3 made of punched metal, wire mesh, etc. is mounted on the upper surface of this electromagnetic absorption thin plate 2, and a template 5 with a mold release layer 4 made of polyethylene or the like formed on the inner surface is arranged at intervals. Two liquids, urethane resin and a blowing agent such as soda carbonate or calcium carbonate, are supplied within the space. As a result, the two liquids react, foam, and expand (Fig. 1A).
このとき型板５は上昇方向の力を付与されるが、外方か
ら、プレス圧ｐを印加することにより、電磁吸収薄板２
と型板５間に所定間隔が維持される。この成形後、前記
型板５は離型層４により剥離されて、電磁吸収薄板２上
に３０〜１００ｍｍ厚の発泡プラスチック層６が形成さ
れる（第１図口）。At this time, the template 5 is given a force in the upward direction, but by applying a press pressure p from the outside, the electromagnetic absorbing thin plate 2
A predetermined distance is maintained between the template 5 and the template 5. After this molding, the mold plate 5 is peeled off by the mold release layer 4, and a foamed plastic layer 6 with a thickness of 30 to 100 mm is formed on the electromagnetic absorbing thin plate 2 (see Figure 1).
そしてこのプラスチック層６の発泡によって、空隙率の
高い疎状となり、その軽量化が実現できる。また、発泡
プラスチック層６は、導電層３の孔を介して、電磁吸収
薄板２の上面と接合することとなり、従って、接着剤を
要することなく、電磁吸収薄板２と発泡プラスチック層
６とは一体化される。By foaming the plastic layer 6, it becomes sparse with high porosity, and its weight can be reduced. Further, the foamed plastic layer 6 is bonded to the upper surface of the electromagnetic absorption thin plate 2 through the holes of the conductive layer 3, so that the electromagnetic absorption thin plate 2 and the foamed plastic layer 6 are integrated into one piece without the need for an adhesive. be converted into
さらに、かかる形成後に発泡プラスチック層６の外面に
は、鉄板、銅板または導電性ゴムシート等の導体板７が
接合される（第１図ハ）。Further, after this formation, a conductor plate 7 such as an iron plate, a copper plate, or a conductive rubber sheet is bonded to the outer surface of the foamed plastic layer 6 (FIG. 1C).
尚、電磁吸収薄板２上に発泡プラスチック層６を形成す
る他の手段として、その樹脂材料に対応し、発泡射出成
形、型物成形等の種々の公知の発泡成形法が採用され得
る。また、発泡プラスチック層６の他側としては、発泡
フェノール樹脂１允泡スチロール樹脂等の種々の発泡材
料が考えられ得る。As other means for forming the foamed plastic layer 6 on the electromagnetic absorbing thin plate 2, various known foaming methods such as foaming injection molding and molding may be adopted depending on the resin material. Further, as the other side of the foamed plastic layer 6, various foamed materials such as foamed phenol resin and 1-layer foamed styrene resin can be considered.
この電波吸収基材ｌは、複数接合して、電波暗室を構築
する。この時、各電波吸収基材ｌは、前記有孔導電層３
を夫々接続することにより、電気的導通が施される。こ
の各電波吸収基材ｌの接合は、第２図に示すように、そ
の接合端縁に、凹凸面８ａ、８ｂを形成しておいて、相
互にアルミナーブ、銅テープ等の導電性テープ９または
充填剤アルミニュウム、銅等の導電性充填剤を介して当
接する。そしてこの、導電性テープ９又は導電性充填剤
により、各電波吸収基材ｌの有孔導電層３を電気的に接
続する。更には、発泡プラスチック層６に連結金具１０
を埋入して、固定することにより施され得る。A plurality of these radio wave absorbing base materials 1 are joined together to construct a radio wave anechoic chamber. At this time, each radio wave absorbing base material l has the aforementioned porous conductive layer 3.
Electrical continuity is established by connecting them to each other. As shown in FIG. 2, the radio wave absorbing base materials 1 are bonded by forming uneven surfaces 8a and 8b on their bonding edges, and then attaching them to each other using conductive tape 9 such as aluminum or copper tape. Contact is made through a conductive filler such as aluminum or copper. Then, the conductive tape 9 or the conductive filler electrically connects the perforated conductive layers 3 of each radio wave absorbing base material 1. Furthermore, a connecting fitting 10 is attached to the foamed plastic layer 6.
This can be done by embedding and fixing.
かかる構成にあって、電波吸収基材ｌに入射した電磁波
は、酸化物磁性材料層からなる電磁吸収薄板２に入射し
、層内に閉じ込められて反射を繰り返して、有孔導電層
３に反射して再入射し、誘電損を生じて減衰消失する。With such a configuration, the electromagnetic wave that has entered the radio wave absorbing base material l enters the electromagnetic absorbing thin plate 2 made of an oxide magnetic material layer, is confined within the layer, is repeatedly reflected, and is reflected by the perforated conductive layer 3. The light then re-enters the field, causing dielectric loss and attenuating and disappearing.
また電波吸収基材１の裏面に形成した導体板７により、
電磁シールドが施される。In addition, the conductor plate 7 formed on the back side of the radio wave absorbing base material 1 allows
Electromagnetic shielding is applied.
前記電波吸収基材ｌの前面には、第３図に示すように、
四角錐からなる電波吸収体１１を配設するようにしても
良い、この電波吸収体１１の傾斜面により、非直交方向
からの電波に対する吸収能力が向上する。As shown in FIG. 3, on the front surface of the radio wave absorbing base material l,
The radio wave absorber 11 made of a quadrangular pyramid may be disposed, and the inclined surface of the radio wave absorber 11 improves the ability to absorb radio waves from non-orthogonal directions.
さらには、前記発泡プラスチック層６には、カーボン粉
末を分散させ、電波の捕捉帯域を拡大することができる
。Furthermore, by dispersing carbon powder in the foamed plastic layer 6, the radio wave capture band can be expanded.
このカーボン粉末の分散は、導体板７を接合する前に、
発泡プラスチック層６をカーボンを含有する液槽に浸漬
することにより施される。かかる構成にあっては、電波
はカーボン粉末との衝突で、導電層または誘電損を生じ
て、その減衰がさらに効率的になされることとなる。そ
してカーボンは、フェライトよりも、高い周波数帯域に
対する吸収能を有するから、電波吸収基材ｌの吸収帯域
幅を拡大することができることとなる。This carbon powder is dispersed before joining the conductor plate 7.
It is applied by immersing the foamed plastic layer 6 in a liquid bath containing carbon. In such a configuration, the radio waves collide with the carbon powder, causing a conductive layer or dielectric loss, and the attenuation is made more efficient. Since carbon has a higher frequency band absorption ability than ferrite, it is possible to expand the absorption bandwidth of the radio wave absorbing base material l.
尚、カーボン粉末に換えて、フェライト等の粉末を混入
する場合もあり、またカーボン粉末と共に、混合する場
合もあり得る。いずれも、所望の吸収周波数帯域に対応
して選定され得る。Note that powder such as ferrite may be mixed instead of carbon powder, or may be mixed together with carbon powder. Any of them can be selected depending on the desired absorption frequency band.
また前記電磁吸収薄板２は、ゴムフェライトにより構成
しても良い、該ゴムフェライトは、焼結フェライトとは
異なり、 ２ＧＨｚ〜５ＧＨｚの周波数帯域の電磁波を
吸収し得る能力が知られている。Further, the electromagnetic absorbing thin plate 2 may be made of rubber ferrite, which, unlike sintered ferrite, is known for its ability to absorb electromagnetic waves in the frequency band of 2 GHz to 5 GHz.
以上のような材料選定及び付加構成ににより、用途に応
じた特性を達成し得ることとなる。そして、広い帯域の
周波数を吸収するもの（Ｗ形電波吸収基材）、特定の周
波数のみを吸収するために用いるもの（Ｎ形電波吸収基
材）等の、特性選定が可能となる。By selecting materials and adding configurations as described above, characteristics depending on the application can be achieved. Then, it is possible to select characteristics such as one that absorbs a wide range of frequencies (W-type radio wave absorption base material) and one that is used to absorb only a specific frequency (N-type radio wave absorption base material).
〈発明の効果〉
本発明は、上述の様に、電磁吸収薄板２の上面に有孔導
電層３を介して発泡プラスチック層６を形成することに
より電波吸収基材ｌを製造するようにしたから、
１）電磁吸収薄板２の保持と、その接合を容易に施すこ
とができる。<Effects of the Invention> As described above, in the present invention, the radio wave absorbing base material l is manufactured by forming the foamed plastic layer 6 on the upper surface of the electromagnetic absorbing thin plate 2 via the perforated conductive layer 3. 1) The electromagnetic absorbing thin plate 2 can be easily held and joined.
２） 発泡プラスチック層６の成形と共に、電磁吸収薄
板２を接合し得るから接着剤等を要しないで、全面接合
が可能となる。2) Since the electromagnetic absorbing thin plate 2 can be joined together with the molding of the foamed plastic layer 6, the entire surface can be joined without the need for an adhesive or the like.
３） 接合工程を要せず、製造が簡易となり、量産に適
する。3) No bonding process is required, making manufacturing simple and suitable for mass production.
４） 発泡プラスチック層６により、軽量化が可能とな
り、取り扱い及び構築が容易となる。4) The foamed plastic layer 6 allows for weight reduction and ease of handling and construction.
等の優れた効果がある。It has excellent effects such as
添付図面は本発明の実施例を示し、第１図は電波吸収基
材ｌの製造工程を示す説明図、第２図は電波吸収基材ｌ
の連結手段を示す縦断側面図、第３図は電波吸収基材ｌ
の使用例を示す縦断側面図である。
箪１品
ｌ・・・電波吸収基材
２・・・電磁吸収薄板
３・・・有孔導電層
５・・・型機
６・・・発泡プラスチック層
７・・・導体板
１１・・・電波吸収体
＝＝〉The attached drawings show examples of the present invention, and FIG. 1 is an explanatory diagram showing the manufacturing process of the radio wave absorbing base material l, and FIG. 2 is an explanatory diagram showing the manufacturing process of the radio wave absorbing base material l.
3 is a vertical cross-sectional side view showing the connection means of the radio wave absorbing base l
FIG. 1 item L... Radio wave absorbing base material 2... Electromagnetic absorbing thin plate 3... Perforated conductive layer 5... Mold machine 6... Foamed plastic layer 7... Conductor plate 11... Radio wave Absorber ==>
Claims (1)
チック層を所定厚に成形し、更に成形された発泡プラス
チック層の外面に、導体板を接合してなることを特徴と
する電波吸収基材の製造方法。A radio wave absorbing substrate characterized by forming a foamed plastic layer to a predetermined thickness on an electromagnetic absorption thin plate via a perforated conductive layer, and further bonding a conductive plate to the outer surface of the formed foamed plastic layer. Method of manufacturing wood.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63235473A JP2745016B2 (en) | 1988-09-19 | 1988-09-19 | Manufacturing method of radio wave absorbing substrate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63235473A JP2745016B2 (en) | 1988-09-19 | 1988-09-19 | Manufacturing method of radio wave absorbing substrate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0282600A true JPH0282600A (en) | 1990-03-23 |
| JP2745016B2 JP2745016B2 (en) | 1998-04-28 |
Family
ID=16986596
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63235473A Expired - Fee Related JP2745016B2 (en) | 1988-09-19 | 1988-09-19 | Manufacturing method of radio wave absorbing substrate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2745016B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114455960A (en) * | 2022-01-20 | 2022-05-10 | 烟台大学 | Metal/ceramic wave-absorbing composite material and preparation method thereof |
| CN115891800A (en) * | 2022-11-10 | 2023-04-04 | 扬州阿特兰新材料有限公司 | Car carpet with electromagnetic shielding function and preparation method thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58210696A (en) * | 1982-06-02 | 1983-12-07 | ティーディーケイ株式会社 | Radio wave absorber |
| JPS62177998A (en) * | 1986-01-31 | 1987-08-04 | ティーディーケイ株式会社 | Electromagnetic wave absorber |
-
1988
- 1988-09-19 JP JP63235473A patent/JP2745016B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58210696A (en) * | 1982-06-02 | 1983-12-07 | ティーディーケイ株式会社 | Radio wave absorber |
| JPS62177998A (en) * | 1986-01-31 | 1987-08-04 | ティーディーケイ株式会社 | Electromagnetic wave absorber |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114455960A (en) * | 2022-01-20 | 2022-05-10 | 烟台大学 | Metal/ceramic wave-absorbing composite material and preparation method thereof |
| CN115891800A (en) * | 2022-11-10 | 2023-04-04 | 扬州阿特兰新材料有限公司 | Car carpet with electromagnetic shielding function and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2745016B2 (en) | 1998-04-28 |
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