JP2016219725A - Radio wave absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio wave absorber having a high radio wave absorption performance, especially for the high frequency band radio waves of 1 to 3 GHz, and is used suitable in an anechoic chamber, for example.SOLUTION: In a radio wave absorber including a first radio wave absorber member of pyramid trapezoid having at least four slopes A to D, and a second radio wave absorber member having two slopes E, F facing each other, upper bases of the slopes E, F are in contact with each other, the slopes A and C are facing, the upper base of the slope A and the base of the slope E are in contact, the upper base of the slope C and the base of the slope F are in contact, the angle of a plane surrounded by the slopes A to D and the slopes A to D is 64° to 68°, and the height is 40 to 110 cm.SELECTED DRAWING: Figure 1

Description

本発明は、電波吸収体に関する。   The present invention relates to a radio wave absorber.

電波暗室とは、電子機器から放射される電磁ノイズ評価、外来電磁ノイズに対する電子機器のイミュニティ評価や、アンテナ特性の評価等を行う測定施設である。電波暗室の壁面や天井面には電波吸収体が用いられており、電波吸収体に要求される吸収周波数帯域は数十ＭＨｚ〜数ＧＨｚである。電波吸収体としては、一般的に、数十〜数百ＭＨｚの吸収を担うフェライトタイルと、ＧＨｚ帯域の吸収を担うカーボンやグラファイト等を含有する発泡ウレタン、発泡ポリスチレンからなるピラミッド型やくさび型吸収体等の立体型吸収体とが組み合わせて使用されている。   An anechoic chamber is a measurement facility that performs evaluation of electromagnetic noise radiated from electronic devices, immunity evaluation of electronic devices against external electromagnetic noise, evaluation of antenna characteristics, and the like. A radio wave absorber is used on the wall or ceiling surface of the anechoic chamber, and the absorption frequency band required for the radio wave absorber is several tens of MHz to several GHz. As an electromagnetic wave absorber, a pyramid type or wedge type absorption generally composed of a ferrite tile that absorbs absorption of several tens to several hundreds of MHz, foamed urethane containing carbon or graphite that supports absorption in the GHz band, and foamed polystyrene. It is used in combination with a three-dimensional absorber such as a body.

尚、近年は、情報伝達量の高密度化に伴い電子機器は高周波化の一途を辿っており、それを評価する電波暗室の要求性能も数ＧＨｚから数十ＧＨｚと高周波に伸びており、高周波帯域の吸収を担う電波吸収体の役割はますます重要になってきている。   In recent years, electronic devices have been increasing in frequency with the increase in the amount of information transmitted, and the required performance of an anechoic chamber for evaluating it has increased from several GHz to several tens of GHz. The role of radio wave absorbers responsible for band absorption is becoming increasingly important.

また、近年では電波吸収特性と騒音低減性能とを同時に兼ね備えた、錐体や錐体台形を規則的に配列した電波音波吸収体が提案されている（特許文献１）。   In recent years, there has been proposed a radio wave absorber that regularly has a pyramid and a trapezoidal trapezoid having both radio wave absorption characteristics and noise reduction performance (Patent Document 1).

また、軽量かつ不燃性の電波吸収体を生産性よく製造するために、珪酸カルシウム板からなる四角錐台と小四角錐を結合した電波吸収体が提案されている（特許文献２）。   Moreover, in order to manufacture a lightweight and non-combustible radio wave absorber with high productivity, a radio wave absorber in which a square pyramid made of a calcium silicate plate and a small square pyramid are combined has been proposed (Patent Document 2).

さらに、優れた電波吸収性能を有し、輸送性、現場施工性などのハンドリング性に優れた、シート材からなる電波吸収体が提案されている（特許文献３）。   Furthermore, a radio wave absorber made of a sheet material that has excellent radio wave absorption performance and excellent handling properties such as transportability and on-site workability has been proposed (Patent Document 3).

また、軽量、低コストで、短い長さで低周波から良好な電波吸収特性が得られる、中空の錐状体の先端に開口を設けた、導電材料を含む電波吸収体が提案されている（特許文献４）。   In addition, a radio wave absorber including a conductive material having an opening at the tip of a hollow cone-like body, which is lightweight, low-cost, and has good radio wave absorption characteristics from a low frequency in a short length, has been proposed ( Patent Document 4).

特開２００３−２４１７６１号公報JP 2003-241761 A 特開平１０−１６３６７０号公報JP-A-10-163670 特開２０１２−１９１１８３号公報JP 2012-191183 A 特開２００５−３４０７３０号公報JP 2005-340730 A

上記の特許文献１に開示された電波音波吸収体は、錐体や錐体台形の形状を採用しているものの、その底部と斜面との角度や高さが不適切であり、電波暗室として要求されている、特に１ＧＨｚ〜３ＧＨｚの高周波帯域における吸収性能に劣るとの課題がある。   Although the radio wave absorber disclosed in the above-mentioned Patent Document 1 adopts a cone or a trapezoidal trapezoidal shape, the angle and height between the bottom and the slope are inappropriate, and it is required as an anechoic chamber. In particular, there is a problem that the absorption performance is inferior in a high frequency band of 1 GHz to 3 GHz.

また、上記の特許文献２に開示された電波吸収体は、四角錐台の上部に小四角錐を結合した四角錐の形状を採用しているものの、その底部と斜面との角度や高さが不適切であり、電波暗室として要求されている、特に１ＧＨｚ〜３ＧＨｚの高周波帯域における吸収性能に劣る。また、電波吸収体の高さが９５６ｍｍと高く、電波暗室の壁面や天井面に貼り付け、施工した後に、電波暗室として利用できる有効利用容積が小さくなるとの課題がある。   In addition, the radio wave absorber disclosed in Patent Document 2 employs a quadrangular pyramid shape in which a small quadrangular pyramid is coupled to the upper portion of the quadrangular pyramid, but the angle and height between the bottom and the slope are different. It is inadequate and is inferior in absorption performance in a high frequency band of 1 GHz to 3 GHz which is required as an anechoic chamber. Further, the height of the electromagnetic wave absorber is as high as 956 mm, and there is a problem that the effective use volume that can be used as the electromagnetic wave anechoic chamber becomes small after being attached to the wall surface or ceiling surface of the electromagnetic wave anechoic chamber.

上記の特許文献３に開示された電波音波吸収体は、四角錐台形に似た形状を採用しているものの、その底部と斜面との角度や高さが不適切であり、電波暗室として要求されている、特に１ＧＨｚ〜３ＧＨｚの高周波帯域における吸収性能に劣るとの課題がある。   Although the electromagnetic wave absorber disclosed in Patent Document 3 employs a shape similar to a quadrangular pyramid trapezoid, the angle and height between the bottom and the slope are inappropriate, and it is required as an anechoic chamber. In particular, there is a problem that the absorption performance is inferior in a high frequency band of 1 GHz to 3 GHz.

上記の特許文献４に開示された電波音波吸収体は、四角錐台形を採用しているものの、実施例に採用している四角錐台形は、底部と斜面との角度が大きいため、電波暗室として要求されている、特に１ＧＨｚ〜３ＧＨｚの高周波帯域における吸収性能に劣るとの課題がある。また、電波吸収体の長さが長いいため、電波暗室の壁面や天井面に貼り付け、施工した後に、電波暗室として利用できる有効利用容積が小さくなるとの課題がある。   Although the electromagnetic wave absorber disclosed in Patent Document 4 employs a quadrangular pyramid trapezoid, the quadrangular pyramid trapezoid employed in the examples has a large angle between the bottom and the slope, so that it is used as an anechoic chamber. There exists a subject that it is inferior in the absorption performance in the high frequency band of 1 GHz-3 GHz especially requested | required. Moreover, since the length of the electromagnetic wave absorber is long, there is a problem that the effective use volume that can be used as the anechoic chamber becomes small after being attached to and constructed on the wall or ceiling surface of the anechoic chamber.

そこで、本発明は、高度な電波吸収性能、特に１ＧＨｚ〜３ＧＨｚの高周波帯域の電波に対し優れた電波吸収性能を有する電波吸収体を提供することを課題とする。   Then, this invention makes it a subject to provide the radio wave absorber which has the high radio wave absorption performance, especially the radio wave absorption performance excellent with respect to the high frequency band of 1 GHz-3 GHz.

上記課題を解決するため、本発明は以下の構成を有する。すなわち、
（１）４つの台形面Ａ、Ｂ、ＣおよびＤを有する第一の電波吸収体部材であって、これら台形面Ａ、Ｂ、ＣおよびＤがこの順に隣り合い四角錐台形の斜面を構成するように配置された第一の電波吸収体部材と、２つの四角形面ＥおよびＦを有する第二の電波吸収体部材であって、これら四角形面ＥおよびＦとで１辺を共有する２つの斜面を構成するように配置された第二の電波吸収体部材と、を有する電波吸収体であって、前記四角形面Ｅの前記四角形面Ｆと共有する辺に対向する辺が、前記台形面Ａの上底と共有しており、前記四角形面Ｆの前記四角形面Ｅと共有する辺に対向する辺が、前記台形面Ｃの上底と共有しており、前記台形面Ａ、Ｂ、ＣおよびＤの各下底を通る平面と、前記台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６４°以上６８°以下であり、高さが４０ｃｍ以上１１０ｃｍ以下である、電波吸収体、
（２）前記台形面Ａ、Ｂ、ＣおよびＤがいずれも同じ形状の等脚台形である、（１）の電波吸収体、
（３）前記台形面Ａ、Ｂ、ＣおよびＤ並びに前記四角形面ＥおよびＦが、３ＧＨｚにおける複素比誘電率の実部εｒ’が７以上１８以下であり、虚部εｒ”が４以上１５以下である電波吸収体用シート材から構成された、（１）または（２）の電波吸収体、
（４）前記第二の電波吸収体部材が、前記四角形面ＥおよびＦのそれぞれと１辺を共有する三角形面Ｇ、並びに前記四角形面ＥおよびＦのそれぞれと１辺を共有する三角形面Ｈを有する寄棟形状またはくさび形状であり、前記三角形面Ｇの前記四角形面ＥおよびＦと共有していない辺が、前記台形面Ｂの上底と共有しており、前記三角形面Ｈの前記四角形面ＥおよびＦと共有していない辺が、前記台形面Ｄの上底と共有している、（１）〜（３）のいずれかの電波吸収体、
（５）前記三角形面ＧおよびＨが、３ＧＨｚにおける複素比誘電率の実部εｒ’が７以上１８以下であり、虚部εｒ”が４以上１５以下である電波吸収体用シート材から構成された、（４）の電波吸収体である。 In order to solve the above problems, the present invention has the following configuration. That is,
(1) A first wave absorber member having four trapezoidal surfaces A, B, C, and D, and these trapezoidal surfaces A, B, C, and D are adjacent to each other in this order to form a quadrangular pyramid-shaped slope. The second wave absorber member having the first wave absorber member and the two rectangular surfaces E and F arranged in this manner, and the two inclined surfaces sharing one side with the square surfaces E and F A second wave absorber member arranged so as to constitute a side of the trapezoidal surface A, the side facing the side shared by the square surface F of the square surface E of the trapezoidal surface A A side that is shared with the upper base, and a side opposite to the side shared with the quadrangular surface E of the quadrangular surface F is shared with the upper base of the trapezoidal surface C, and the trapezoidal surfaces A, B, C, and D The angle (acute angle) formed by the plane passing through the lower base of each and the trapezoidal surfaces A, B, C and D Also at 64 ° or more 68 ° or less, the height is less than 110cm least 40 cm, wave absorber Re,
(2) The radio wave absorber according to (1), wherein each of the trapezoidal surfaces A, B, C, and D is an isosceles trapezoid having the same shape,
(3) The trapezoidal surfaces A, B, C and D and the rectangular surfaces E and F have a real part εr ′ of a complex relative dielectric constant at 3 GHz of 7 to 18 and an imaginary part εr ″ of 4 to 15 (1) or (2) radio wave absorber, comprising the radio wave absorber sheet material
(4) The second radio wave absorber member has a triangular surface G sharing one side with each of the square surfaces E and F, and a triangular surface H sharing one side with each of the square surfaces E and F. The side of the triangular surface G that has a dormitory shape or a wedge shape that is not shared with the rectangular surfaces E and F is shared with the upper base of the trapezoidal surface B, and the rectangular surface of the triangular surface H The radio wave absorber according to any one of (1) to (3), wherein the side not shared with E and F is shared with the upper base of the trapezoidal surface D,
(5) The triangular surfaces G and H are made of a sheet material for a radio wave absorber in which the real part εr ′ of the complex relative permittivity at 3 GHz is 7 or more and 18 or less and the imaginary part εr ″ is 4 or more and 15 or less. In addition, the electromagnetic wave absorber (4).

本発明によれば、高度な電波吸収性能、特に１ＧＨｚ〜３ＧＨｚの高周波帯域の電波に対し優れた電波吸収性能を有する電波吸収体を得ることができる。   According to the present invention, it is possible to obtain a radio wave absorber having high radio wave absorption performance, particularly excellent radio wave absorption performance for radio waves in a high frequency band of 1 GHz to 3 GHz.

本発明の電波吸収体の一例の斜視概念図。The perspective view of an example of the electromagnetic wave absorber of this invention. 図１の電波吸収体の側面概念図。The side surface conceptual diagram of the electromagnetic wave absorber of FIG. 図２の電波吸収体を９０度回転させたものの側面概念図。The side surface conceptual diagram of what rotated the radio wave absorber of FIG. 2 90 degree | times. 図１の電波吸収体に用いられている第二の電波吸収体部材の斜視概念図。The perspective conceptual diagram of the 2nd electromagnetic wave absorber member used for the electromagnetic wave absorber of FIG. 図１の電波吸収体に用いられている第一の電波吸収体部材の斜視概念図。The perspective conceptual diagram of the 1st electromagnetic wave absorber member used for the electromagnetic wave absorber of FIG. 図１の電波吸収体に用いられている第一の電波吸収体部材を上方から見た概念図。The conceptual diagram which looked at the 1st electromagnetic wave absorber member used for the electromagnetic wave absorber of FIG. 1 from upper direction. 四角形面ＥおよびＦ並びに三角形面ＧおよびＨを有する第二の電波吸収体部材の斜視概念図。The perspective conceptual diagram of the 2nd electromagnetic wave absorber member which has the square surfaces E and F and the triangular surfaces G and H. 図７の第二の電波吸収体部材を上方からみた概念図。The conceptual diagram which looked at the 2nd electromagnetic wave absorber member of FIG. 7 from upper direction. 本発明の電波吸収体の別の一例の側面概念図。The side surface conceptual diagram of another example of the electromagnetic wave absorber of this invention. 底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）との角度が、いずれも６４°以上６８°以下の２つの電波吸収体による電波吸収のメカニズムを示す概念図。The conceptual diagram which shows the mechanism of the electromagnetic wave absorption by two electromagnetic wave absorbers whose angle (angular angle) which the bottom part and the trapezoid surface A, B, C, and D each comprise is 64 degrees or more and 68 degrees or less. 底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）が、６４°を下回る２つの電波吸収体による電波吸収のメカニズムを示す概念図。The conceptual diagram which shows the mechanism of the electromagnetic wave absorption by the two electromagnetic wave absorbers in which the angle (acute angle) which the bottom part and trapezoid surface A, B, C, and D form is less than 64 degrees.

以下、本発明の実施の形態を詳細に説明する。本発明の電波吸収体は、第一の電波吸収体部材および第二の電波吸収体部材を備えるものである。   Hereinafter, embodiments of the present invention will be described in detail. The radio wave absorber of the present invention comprises a first radio wave absorber member and a second radio wave absorber member.

また、第一の電波吸収体部材は、４つの台形面Ａ、Ｂ、ＣおよびＤを有する第一の電波吸収体部材であって、これら台形面Ａ、Ｂ、ＣおよびＤがこの順に隣り合い四角錐台形の斜面を構成するように配置されたものである。第一の電波吸収体部材を、四角錐台形とすることにより、角錐形状に比べ、吸収体の高さを低く抑えつつ、かつ、高度な吸収性能、特に１ＧＨｚ〜３ＧＨｚの高周波帯域の電波に対し優れた吸収性能を有する電波吸収体を得ることができる。なお、本発明においては、各台形面の平行な２辺のうちの短い方を「上底」、長い方を「下底」とする。また、詳細は後述するが、本発明では、台形面Ａ、Ｂ、ＣおよびＤの各下底を通る平面と、台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６４°以上６８°以下であることが重要である。また、後述するように、第一の電波吸収体が電波吸収体用シート材を折り曲げ加工することで作製されるもので中空の構造である場合には、台形面Ａ、Ｂ、ＣおよびＤの各下底を通る平面（以下、底部とすることがある。）には電波吸収体用シート材から構成される底面が配されていてもよいし、上記の底面が配されていなくてもよい。   The first wave absorber member is a first wave absorber member having four trapezoidal surfaces A, B, C, and D, and these trapezoidal surfaces A, B, C, and D are adjacent to each other in this order. It is arranged so as to constitute a quadrangular frustum-shaped slope. By making the first radio wave absorber member a quadrangular pyramid trapezoidal shape, the height of the absorber is kept lower than that of the pyramid shape, and high absorption performance, particularly for radio waves in a high frequency band of 1 GHz to 3 GHz. A radio wave absorber having excellent absorption performance can be obtained. In the present invention, the shorter one of the two parallel sides of each trapezoidal surface is referred to as “upper bottom”, and the longer one is referred to as “lower bottom”. Although details will be described later, in the present invention, the angle (acute angle) formed between the plane passing through the lower bases of the trapezoidal surfaces A, B, C and D and the trapezoidal surfaces A, B, C and D is 64. It is important that the angle is not less than 60 ° and not more than 68 °. As will be described later, when the first wave absorber is formed by bending a sheet material for the wave absorber and has a hollow structure, the trapezoidal surfaces A, B, C and D A plane passing through each lower base (hereinafter sometimes referred to as a bottom portion) may be provided with a bottom surface made of a sheet material for a radio wave absorber, or may not be provided with the above bottom surface. .

また、第二の電波吸収体部材は、２つの四角形面ＥおよびＦを有するものであって、これら四角形面ＥおよびＦとで１辺を共有する２つの斜面を構成するように配置されたものである。ここで、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺は、台形面Ａの上底と共有しており、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺は、台形面Ｃの上底と共有している。本発明の電波吸収体は、このような第二の電波吸収体部材を有することで、第一の電波吸収体部材のみの状態、すなわち四角錐台形状の電波吸収体に比べ、四角錐台形状の上面での電波の反射を抑制でき、電波吸収体の吸収性能を向上できるものとなる。   The second wave absorber member has two rectangular surfaces E and F, and is arranged so as to form two inclined surfaces sharing one side with the rectangular surfaces E and F. It is. Here, the side opposite to the side shared by the quadrangle surface F of the quadrangle surface E is shared with the upper base of the trapezoid surface A, and the side opposite to the side shared by the quadrangle surface E of the quadrangle surface F is the trapezoid. Shared with top of surface C. The radio wave absorber of the present invention has such a second radio wave absorber member, so that the state of only the first radio wave absorber member, that is, a quadrangular frustum-shaped wave absorber, compared to a quadrangular frustum-shaped radio wave absorber. It is possible to suppress the reflection of the radio wave on the upper surface of the, and improve the absorption performance of the radio wave absorber.

ここで、図１は、本発明の電波吸収体の一例を示す斜視概念図である。その電波吸収体は、第一の電波吸収体部材２３および第二の電波吸収体部材２４を備えており、第一の電波吸収体部材２３は台形面Ａ、Ｂ、ＣおよびＤを有している（図１では、台形面Ａ２と台形面Ｄ２０のみが図示されている）。また、底部１は、上述のとおり台形面Ａ、Ｂ、ＣおよびＤの各下底を通る平面である。第二の電波吸収体部材２４は四角形面Ｅ４およびＦ２１を有しており、これら四角形面Ｅ４およびＦ２１とで１辺を共有する２つの斜面を構成するように配置されたものである。また、四角形面Ｅ４の四角形面Ｆ２１と共有する辺に対向する辺は、台形面Ａ２の上底と共有しており、四角形面Ｆ２１の四角形面Ｅ４と共有する辺に対向する辺は、台形面Ｃの上底と共有している。   Here, FIG. 1 is a perspective conceptual view showing an example of the radio wave absorber of the present invention. The radio wave absorber includes a first radio wave absorber member 23 and a second radio wave absorber member 24, and the first radio wave absorber member 23 has trapezoidal surfaces A, B, C, and D. (Only the trapezoidal surface A2 and the trapezoidal surface D20 are shown in FIG. 1). Moreover, the bottom part 1 is a plane which passes through each lower base of the trapezoid surface A, B, C, and D as above-mentioned. The second radio wave absorber member 24 has quadrangular surfaces E4 and F21, and is arranged so as to constitute two inclined surfaces sharing one side with the quadrangular surfaces E4 and F21. Further, the side facing the side shared with the quadrangular surface F21 of the quadrangle surface E4 is shared with the upper base of the trapezoid surface A2, and the side facing the side shared with the quadrangle surface E4 of the quadrangle surface F21 is the trapezoid surface. Shared with the bottom of C.

図２は、図１の電波吸収体の側面概念図であり、図１に示す電波吸収体を、台形面Ｄが正面となる方向から見たときの側面概念図であり、図３は、図２の電波吸収体を、その底部の中心点を通り底部に垂直な軸を中心に９０度回転させたものの側面概念図、すなわち、図１に示す電波吸収体を、台形面Ａが正面となる方向から見たときの側面概念図である。なお、図１〜３に示される本発明の電波吸収体の一例では、図３に示されるとおり、四角形面ＥおよびＦとで共有される１辺と第１の電波吸収体部材の底部とが平行となっている。   2 is a conceptual side view of the radio wave absorber shown in FIG. 1. FIG. 2 is a conceptual side view of the radio wave absorber shown in FIG. 1 when viewed from the direction in which the trapezoidal surface D is the front. 2 is a conceptual side view of the electromagnetic wave absorber 2 rotated 90 degrees about an axis passing through the center point of the bottom portion and perpendicular to the bottom portion, that is, the electromagnetic wave absorber shown in FIG. It is a side conceptual diagram when it sees from a direction. In the example of the radio wave absorber of the present invention shown in FIGS. 1 to 3, as shown in FIG. 3, one side shared by the square surfaces E and F and the bottom of the first radio wave absorber member are It is parallel.

また、本発明の電波吸収体では、詳細は後述するが、台形面Ａ、Ｂ、ＣおよびＤの各下底を通る平面（底部）と、台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６４°以上６８°以下であることが重要である。ここで、例えば、底部と台形面Ａとの成す角度（鋭角）２６は、図１〜３などに図示されている。また、底部と、台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）は、全て同じ角度であってもよいし、本発明の効果を阻害しない範囲において、それぞれ異なるものであってもよい。   Further, in the radio wave absorber of the present invention, as will be described in detail later, an angle formed by a plane (bottom part) passing through the lower bases of the trapezoidal surfaces A, B, C and D and the trapezoidal surfaces A, B, C and D It is important that the (acute angle) is 64 ° or more and 68 ° or less. Here, for example, an angle (acute angle) 26 formed by the bottom and the trapezoidal surface A is illustrated in FIGS. Further, the angles (acute angles) formed by the bottom and the trapezoidal surfaces A, B, C, and D may all be the same angle, or may be different within a range that does not impair the effects of the present invention. Good.

図４は、図１の電波吸収体に用いられている第二の電波吸収体部材の斜視概念図を示す。本発明の電波吸収体が備える第二の電波吸収体２４は、四角形面Ｅ４およびＦ２１を有しており、これら四角形面Ｅ４およびＦ２１とで１辺を共有する２つの斜面を構成するように配置されたものである。また、四角形面Ｅ４の四角形面Ｆ２１と共有する辺に対向する辺は、台形面Ａ２の上底と共有しており、四角形面Ｆ２１の四角形面Ｅ４と共有する辺に対向する辺は、台形面Ｃの上底と共有している。   FIG. 4 is a perspective conceptual view of a second radio wave absorber member used in the radio wave absorber of FIG. The second radio wave absorber 24 included in the radio wave absorber of the present invention has quadrangular surfaces E4 and F21, and is arranged so as to form two slopes sharing one side with the quadrangular surfaces E4 and F21. It has been done. Further, the side facing the side shared with the quadrangular surface F21 of the quadrangle surface E4 is shared with the upper base of the trapezoid surface A2, and the side facing the side shared with the quadrangle surface E4 of the quadrangle surface F21 is the trapezoid surface. Shared with the bottom of C.

また、図５は、図１の電波吸収体に用いられている第一の電波吸収体部材の斜視概念図を示す。図５で示した電波吸収体の形態では、その第一の電波吸収体部材２３は、４つの台形面Ａ、Ｂ、ＣおよびＤを有し、底部と向かい合う上面を有しないが、本発明の電波吸収体の別の形態では、４つの台形面Ａ、Ｂ、ＣおよびＤに加えて、底部と向かい合う上面を有していてもよい。   5 shows a perspective conceptual view of a first radio wave absorber member used in the radio wave absorber of FIG. In the form of the radio wave absorber shown in FIG. 5, the first radio wave absorber member 23 has four trapezoidal surfaces A, B, C, and D, and does not have an upper surface facing the bottom. In another form of the radio wave absorber, in addition to the four trapezoidal surfaces A, B, C and D, an upper surface facing the bottom may be provided.

また、図６は、図１の電波吸収体に用いられている第一の電波吸収体部材を上方から見た概念図を示す。この第一の電波吸収体部材は、台形面Ａ２、台形面Ｂ１８、台形面Ｃ１９および台形面Ｄ２０を有する。   Moreover, FIG. 6 shows the conceptual diagram which looked at the 1st electromagnetic wave absorber member used for the electromagnetic wave absorber of FIG. 1 from upper direction. The first wave absorber member has a trapezoidal surface A2, a trapezoidal surface B18, a trapezoidal surface C19, and a trapezoidal surface D20.

また、図１で示した電波吸収体の一例では、その第二の電波吸収体部材２４は、２つの四角形面ＥおよびＦを有するが、本発明の電波吸収体の別の形態では、それらの２つの四角形面ＥおよびＦに加えて、さらに、四角形面ＥおよびＦのそれぞれと１辺を共有する三角形面Ｇ、並びに四角形面ＥおよびＦのそれぞれと１辺を共有する三角形面Ｈを有していてもよい。また、その場合、三角形面Ｇの四角形面ＥおよびＦと共有していない辺（以下、三角形面Ｇの底辺とすることがある）は、台形面Ｂの上底と共有していてもよく、三角形面Ｈの四角形面ＥおよびＦと共有していない辺（以下、三角形面Ｈの底辺とすることがある）は、台形面Ｄの上底と共有していてもよい。なお、第二の電波吸収体部材が、四角形面ＥおよびＦ並びに三角形面ＧおよびＨを有する場合には、本発明の電波吸収体は、底部以外に開口部を有しない構成となり得る。なお、図７は、四角形面ＥおよびＦ並びに三角形面ＧおよびＨを有する第二の電波吸収体部材の斜視概念図を示す。この形態の第二の電波吸収体部材２４は、四角形面Ｅ４、四角形面Ｆ２１、三角形面Ｇ（図７には図示せず）および三角形面Ｈ２２を有する。   In the example of the radio wave absorber shown in FIG. 1, the second radio wave absorber member 24 has two rectangular surfaces E and F. However, in another form of the radio wave absorber of the present invention, those In addition to the two quadrangular surfaces E and F, it further includes a triangular surface G that shares one side with each of the quadrangular surfaces E and F, and a triangular surface H that shares one side with each of the quadrangular surfaces E and F. It may be. In that case, a side that is not shared with the quadrangular surfaces E and F of the triangular surface G (hereinafter, sometimes referred to as a base of the triangular surface G) may be shared with the upper base of the trapezoidal surface B. Sides that are not shared with the quadrangular surfaces E and F of the triangular surface H (hereinafter sometimes referred to as the bottom side of the triangular surface H) may be shared with the upper base of the trapezoidal surface D. In addition, when the 2nd electromagnetic wave absorber member has the square surfaces E and F and the triangular surfaces G and H, the electromagnetic wave absorber of this invention may become a structure which does not have an opening part other than a bottom part. FIG. 7 is a perspective conceptual view of a second radio wave absorber member having square surfaces E and F and triangular surfaces G and H. The second radio wave absorber member 24 in this form has a quadrangular surface E4, a quadrangular surface F21, a triangular surface G (not shown in FIG. 7), and a triangular surface H22.

次に、図８は、図７の第二の電波吸収体部材を上方からみた概念図を示す。第二の電波吸収体部材２４は、四角形面Ｅ４、四角形面Ｆ２１、三角形面Ｇ１７および三角形面Ｈ２２を有する。   Next, FIG. 8 shows a conceptual diagram of the second radio wave absorber member of FIG. 7 as viewed from above. The second radio wave absorber member 24 has a quadrangular surface E4, a quadrangular surface F21, a triangular surface G17, and a triangular surface H22.

また、第二の電波吸収体部材は、その強度を向上させる観点から、四角形面ＥおよびＦに加えて、三角形面ＧおよびＨを有することが好ましい。その形態である場合、電波吸収体の強度をより向上させることができるとの観点から、台形面Ｂの上底と三角形面Ｇの底辺とが接しており、台形面Ｄの上底と三角形面Ｈの底辺とが接していることが好ましい。さらに、第二の電波吸収体部材が、四角形面ＥおよびＦ並びに三角形面ＧおよびＨを有する場合においては、その組み立て性が良好なものとなるとのの観点から、その第二の電波吸収体部材の形状は寄棟形状またはくさび形状であることが好ましい。   Moreover, it is preferable that the 2nd electromagnetic wave absorber member has the triangular surfaces G and H in addition to the square surfaces E and F from a viewpoint of improving the intensity | strength. In that form, the upper base of the trapezoidal surface B and the base of the triangular surface G are in contact with each other from the viewpoint that the strength of the radio wave absorber can be further improved. It is preferable that the bottom side of H is in contact. Furthermore, in the case where the second radio wave absorber member has the square surfaces E and F and the triangular surfaces G and H, the second radio wave absorber member from the viewpoint that the assemblability is good. The shape is preferably a berth shape or a wedge shape.

なお、寄棟形状とは、建物の屋根の形状であって、２つの台形の斜面（四角形面ＥおよびＦがこれに相当する）と２つの三角形の斜面（三角形面ＧおよびＨがこれに相当する）から構成される形状を言う。   The dormitory shape is the shape of the roof of the building, and includes two trapezoidal slopes (square faces E and F correspond to this) and two triangular slopes (triangle faces G and H correspond to this). )).

また、本発明の電波吸収体の一例は、後述するとおり電波吸収体用シート材６を折り曲げ加工することで作製されるもので中空の構造となっている。   Moreover, an example of the radio wave absorber of the present invention is produced by bending the radio wave absorber sheet material 6 as described later and has a hollow structure.

また、本発明の電波吸収体の高さは、後述するとおり特定の範囲内となっている。ここで、本発明の電波吸収体の高さは、第一の電波吸収体部材の底部に対して垂直な垂線が、第一の電波吸収体部材の底部と第二の電波吸収体部材の四角形面ＥまたはＦとの間で最大となる距離をいう。具体的には、図２および３に示す電波吸収体（上述のとおり図２および３は同じ形態の電波吸収体を示す）では、高さ２７が電波吸収体の高さとなる。ここで、図９は、本発明の電波吸収体の別の一例の側面概念図を示す。図９に示す電波吸収体は、図１に示す電波吸収体とは別の形態の電波吸収体であり、四角形面ＥおよびＦとで共有される１辺は、第１の電波吸収体部材の底部に対して平行になっておらず傾いている。このような形態の場合であっても、電波吸収体の高さは、第一の電波吸収体部材の底部に対して垂直な垂線が、第一の電波吸収体部材の底部と第二の電波吸収体部材の四角形面ＧまたはＨとの間で最大となる距離であり、図９に示す電波吸収体では、高さ２８が電波吸収体の高さとなる。   The height of the radio wave absorber of the present invention is within a specific range as will be described later. Here, the height of the radio wave absorber of the present invention is such that the perpendicular perpendicular to the bottom of the first radio wave absorber member is a quadrangle of the bottom of the first radio wave absorber member and the second radio wave absorber member. The maximum distance from the surface E or F. Specifically, in the radio wave absorber shown in FIGS. 2 and 3 (as described above, FIGS. 2 and 3 show the same type of radio wave absorber), the height 27 is the height of the radio wave absorber. Here, FIG. 9 shows the side surface conceptual diagram of another example of the electromagnetic wave absorber of this invention. The radio wave absorber shown in FIG. 9 is a radio wave absorber of a form different from the radio wave absorber shown in FIG. 1, and one side shared by the square surfaces E and F is the same as that of the first radio wave absorber member. It is not parallel to the bottom but tilted. Even in the case of such a configuration, the height of the radio wave absorber is such that the perpendicular perpendicular to the bottom of the first radio wave absorber member is the same as the bottom of the first radio wave absorber member and the second radio wave. This is the maximum distance from the rectangular surface G or H of the absorber member. In the radio wave absorber shown in FIG. 9, the height 28 is the height of the radio wave absorber.

また、安定した電波吸収性能が得られるとの観点から、台形面Ａ、Ｂ、ＣおよびＤは、いずれも同じ形状の等脚台形であることが好ましい。   Further, from the viewpoint of obtaining a stable radio wave absorption performance, it is preferable that the trapezoidal surfaces A, B, C and D are isosceles trapezoids having the same shape.

また、第一の電波吸収体部材の形状は、四角錐台形であるが、安定した電波吸収性能が得られるとの観点から、正四角錐台形であることが好ましい。   Further, the shape of the first radio wave absorber member is a quadrangular pyramid, but it is preferably a regular quadrangular pyramid from the viewpoint that stable radio wave absorption performance can be obtained.

第一の電波吸収体部材は、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６４°以上６８°以下の範囲内である。第一の電波吸収体部材の底部と第一の電波吸収体部材の台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）をいずれも上記の範囲内とすることにより、電波吸収体の上方から入射した電波の多くを電波吸収体に進入させ、その底部まで到達させることができるので、本発明の電波吸収体の電波吸収効率は優れたものとなる。底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）のいずれかが、６４°を下回る場合、本発明の電波吸収体を少なくとも２つ（第１の電波吸収体および第２の電波吸収体）用い、隣接させて配置した際に、電波吸収体の上方から入射した入射電波が、第１の電波吸収体の台形面Ａ、Ｂ、ＣおよびＤで反射され、次いで隣り合う第２の電波吸収体の台形面Ａ、Ｂ、ＣおよびＤで反射され、入射電波の一部が電波吸収体により吸収されず電波吸収体の上方に放射される放射電波となるため、電波吸収体の電波吸収性能が著しく低下する。一方、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）のいずれかが、６８°を超える場合、メカニズムは定かではないものの、電波吸収体の上方から入射した電波と電波吸収体の台形面Ａ、Ｂ、ＣおよびＤとの入射角が大きくなり、結果的に電波吸収体の表面での反射率が大きくなり、電波吸収体の内部に進入する電波の割合が低下するため、電波吸収体の電波吸収性能が著しく低下するものと推測される。上記の観点から、第一の電波吸収体部材の底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）の下限は、いずれも６５°以上が好ましく、その上限は、いずれも６７°以下が好ましく、いずれも６６°以下がより好ましい。   The first wave absorber member has an angle (acute angle) formed between the bottom and the trapezoidal surfaces A, B, C, and D in the range of 64 ° to 68 °. By making the angles (acute angles) formed by the bottom of the first wave absorber member and the trapezoidal surfaces A, B, C and D of the first wave absorber member all fall within the above range, Since most of the radio waves incident from above can enter the radio wave absorber and reach the bottom thereof, the radio wave absorber of the present invention has excellent radio wave absorption efficiency. When any of the angles (acute angles) formed by the bottom and the trapezoidal surfaces A, B, C and D is less than 64 °, at least two of the radio wave absorbers of the present invention (the first radio wave absorber and the second radio wave absorber) When the radio wave absorber is used and arranged adjacent to each other, incident radio waves incident from above the radio wave absorber are reflected by the trapezoidal surfaces A, B, C and D of the first radio wave absorber, and then adjacent The electromagnetic wave absorber is reflected by the trapezoidal surfaces A, B, C and D of the radio wave absorber 2 and a part of the incident radio wave is not absorbed by the radio wave absorber and is radiated above the radio wave absorber. The radio wave absorption performance will be significantly reduced. On the other hand, if any of the angles (acute angles) formed by the bottom and the trapezoidal surfaces A, B, C, and D exceeds 68 °, the mechanism is not clear, but the radio wave incident from above the radio wave absorber and the radio wave absorption. Incident angles with the trapezoidal surfaces A, B, C, and D of the body are increased, and as a result, the reflectance at the surface of the radio wave absorber is increased, and the proportion of radio waves entering the radio wave absorber is reduced. It is estimated that the radio wave absorption performance of the radio wave absorber is significantly lowered. From the above viewpoint, the lower limit of the angle (acute angle) formed by the bottom of the first wave absorber member and the trapezoidal surfaces A, B, C, and D is preferably 65 ° or more, and the upper limit thereof is 67. The angle is preferably at most °, and more preferably at most 66 °.

ここで、図１０は、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）との角度が、いずれも６４°以上６８°以下の２つの電波吸収体（第１の電波吸収体および第２の電波吸収体）による電波吸収のメカニズムを示す概念図であり、図１１は、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）が、６４°を下回る２つの電波吸収体（第１の電波吸収体および第２の電波吸収体）による電波吸収のメカニズムを示す概念図である。底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）が、いずれも６４°以上６８°以下の電波吸収体を用いた場合、電波吸収体の上方からの入射電波７の一部は第１の電波吸収体８の台形面Ａ、Ｂ、ＣおよびＤにて第１の電波吸収体８に進入する。また、第１の電波吸収体８に進入しなかった入射電波７は反射電波１０となり、その一部が第２の電波吸収体９に進入し第２の電波吸収体９の底部に至る。また、第２の電波吸収体９に進入しなかった反射電波１０は反射電波１１となり、反射電波１１は再び第１の電波吸収体８の台形面Ａ、Ｂ、ＣおよびＤに至る。ここで、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）が、６４°を下回る電波吸収体を用いた場合、電波吸収体の上方からの入射電波７の一部は第１の電波吸収体８の台形面Ａ、Ｂ、ＣおよびＤにて第１の電波吸収体８に進入する。また、第１の電波吸収体８に進入しなかった入射電波７は反射電波１０となり、第２の電波吸収体９の台形面Ａ、Ｂ、ＣおよびＤに至る。ここで、反射電波１０の一部は、第２の電波吸収体９の台形面Ａ、Ｂ、ＣおよびＤで反射し、電波吸収体に吸収されることなく、電波吸収体の上方に放射される放射電波１２となる。ここで、入射電波７の入射角Ｍおよび反射電波１０の反射角Ｎは、電波吸収体１の底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）によって変わる。   Here, FIG. 10 shows two radio wave absorbers (first radio wave absorbers) whose angles between the bottom and the trapezoidal surfaces A, B, C, and D (acute angles) are 64 ° to 68 °. FIG. 11 is a conceptual diagram showing the mechanism of radio wave absorption by the body and the second radio wave absorber), and FIG. 11 shows that the angle (acute angle) formed by the bottom and the trapezoidal surfaces A, B, C, and D is less than 64 ° 2 It is a conceptual diagram which shows the mechanism of the electromagnetic wave absorption by two electromagnetic wave absorbers (a 1st electromagnetic wave absorber and a 2nd electromagnetic wave absorber). Part of the incident radio wave 7 from above the radio wave absorber when the wave absorber having an angle (acute angle) between the bottom and the trapezoidal surfaces A, B, C, and D is 64 ° to 68 °. Enters the first wave absorber 8 at the trapezoidal surfaces A, B, C and D of the first wave absorber 8. Further, the incident radio wave 7 that has not entered the first radio wave absorber 8 becomes a reflected radio wave 10, and a part thereof enters the second radio wave absorber 9 and reaches the bottom of the second radio wave absorber 9. The reflected radio wave 10 that has not entered the second radio wave absorber 9 becomes a reflected radio wave 11, and the reflected radio wave 11 reaches the trapezoidal surfaces A, B, C, and D of the first radio wave absorber 8 again. Here, when a radio wave absorber having an angle (acute angle) between the bottom and the trapezoidal surfaces A, B, C, and D is less than 64 °, a part of the incident radio wave 7 from above the radio wave absorber is The first radio wave absorber 8 enters the first radio wave absorber 8 at the trapezoidal surfaces A, B, C, and D. Further, the incident radio wave 7 that has not entered the first radio wave absorber 8 becomes the reflected radio wave 10 and reaches the trapezoidal surfaces A, B, C, and D of the second radio wave absorber 9. Here, a part of the reflected radio wave 10 is reflected by the trapezoidal surfaces A, B, C and D of the second radio wave absorber 9 and is emitted above the radio wave absorber without being absorbed by the radio wave absorber. The radiated radio wave 12 becomes. Here, the incident angle M of the incident radio wave 7 and the reflection angle N of the reflected radio wave 10 vary depending on the angle (acute angle) formed by the bottom of the radio wave absorber 1 and the trapezoidal surfaces A, B, C, and D.

また、本発明の電波吸収体は、高さは４０ｃｍ以上１１０ｃｍ以下である。電波吸収体の高さを４０ｃｍ以上とすることで、高度な吸収性能、特に１ＧＨｚ〜３ＧＨｚの高周波帯域の電波に対し優れた吸収性能を有する電波吸収体を得ることができる。電波吸収体の高さと、電波吸収性能が高まる周波数域、つまり電波の波長には相関があり、本発明の形状で、特に１ＧＨｚ〜３ＧＨｚの高周波帯域の電波に対し高度な吸収性能を得ようとする場合、電波吸収体の高さを４０ｃｍ以上とする必要がある。上記の観点から、本発明の電波吸収体の高さの下限は５０ｃｍ以上が好ましい。一方、電波吸収体の高さを１１０ｃｍ以下とすることで、高度な吸収性能、特に１ＧＨｚ〜３ＧＨｚの高周波帯域の電波に対し優れた吸収性能を有する電波吸収体を得ることができる。上記の観点から、本発明の電波吸収体の高さの上限は６０ｃｍ以下が好ましい。また、本発明の電波吸収体の高さを６０ｃｍ以下とすることで、電波暗室の壁面や天井面に貼り付け、施工した際に、その電波暗室内の有効利用容積を大きくとることも可能となり、電波暗室の実用においてその利便性が飛躍的に向上する。上記の通り、電波吸収体の高さが４０ｃｍ未満または１１０ｃｍを超える場合には、特に１ＧＨｚ〜３ＧＨｚの高周波帯域の電波に対し高度な電波吸収性能が得られない。   In addition, the radio wave absorber of the present invention has a height of 40 cm to 110 cm. By setting the height of the radio wave absorber to 40 cm or more, it is possible to obtain a radio wave absorber having high absorption performance, particularly excellent absorption performance for radio waves in a high frequency band of 1 GHz to 3 GHz. There is a correlation between the height of the radio wave absorber and the frequency range where the radio wave absorption performance is enhanced, that is, the wavelength of the radio wave, and in the shape of the present invention, an attempt is made to obtain a high absorption performance particularly for radio waves in the high frequency band of 1 GHz to 3 GHz. In this case, the height of the radio wave absorber needs to be 40 cm or more. From the above viewpoint, the lower limit of the height of the radio wave absorber of the present invention is preferably 50 cm or more. On the other hand, by setting the height of the radio wave absorber to 110 cm or less, it is possible to obtain a radio wave absorber having high absorption performance, particularly excellent absorption performance for radio waves in a high frequency band of 1 GHz to 3 GHz. From the above viewpoint, the upper limit of the height of the radio wave absorber of the present invention is preferably 60 cm or less. In addition, by setting the height of the electromagnetic wave absorber of the present invention to 60 cm or less, it becomes possible to increase the effective use volume in the anechoic chamber when it is attached to the wall or ceiling surface of the anechoic chamber. In the practical use of the anechoic chamber, the convenience is greatly improved. As described above, when the height of the radio wave absorber is less than 40 cm or exceeds 110 cm, high radio wave absorption performance cannot be obtained particularly for radio waves in a high frequency band of 1 GHz to 3 GHz.

電波吸収体の高さと電波吸収体の電波吸収性能の関係、および、電波吸収体の第一の電波吸収体部材の底部と斜面Ａ〜Ｄとの角度と電波吸収体の電波吸収性能の関係は上記のとおりであるが、本発明者は、本発明の電波吸収体の第一の電波吸収体部材を、その底部とその台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）をいずれも６４°以上６８°以下とし、かつ、電波吸収体の高さを４０ｃｍ以上１１０ｃｍ以下とすることで、特に１ＧＨｚ〜３ＧＨｚの高周波帯域の電波に対する吸収性能が顕著に優れたものとなることを見いだした。   The relationship between the height of the radio wave absorber and the radio wave absorption performance of the radio wave absorber, and the relationship between the angle between the bottom of the first radio wave absorber member and the slopes A to D of the radio wave absorber and the radio wave absorption performance of the radio wave absorber As described above, the present inventor has changed the angle (acute angle) between the bottom of the first wave absorber member of the wave absorber of the present invention and the trapezoidal surfaces A, B, C, and D. In addition, it has been found that the absorption performance with respect to radio waves in the high frequency band of 1 GHz to 3 GHz is remarkably improved by setting the height of the radio wave absorber to 40 cm or more and 110 cm or less. It was.

本発明の電波吸収体の第一の電波吸収体部材が正四角錐台形である場合、その底部は正方形であり、そのサイズは、その１辺の長さが５０ｃｍ以上７０ｃｍ以下であることが好ましく、下限については５５ｃｍ以上がより好ましく、上限については６５ｃｍ以下がより好ましい。このようなサイズとすることで、電波暗室の壁面や天井面に貼り付けが容易となり施工性が向上する。１辺の長さを５０ｃｍ以上とすることで、施工に必要となる電波吸収体の個数が少なくなり、電波吸収体の組み立て工程や電波吸収体の取り付け工程に要する時間をより少なくすることができる。一方、１辺の長さを７０ｃｍ以下とすることで、電波吸収体のサイズを小さな物とすることができ、電波暗室の壁面や天井面に電波吸収体を貼り付ける際の、電波吸収体のハンドリング性が向上する。   When the first radio wave absorber member of the radio wave absorber of the present invention is a regular quadrangular pyramid trapezoid, its bottom is a square, and the size of one side is preferably 50 cm or more and 70 cm or less, The lower limit is more preferably 55 cm or more, and the upper limit is more preferably 65 cm or less. By setting it as such a size, affixing to the wall surface and ceiling surface of an anechoic chamber becomes easy, and workability improves. By setting the length of one side to 50 cm or more, the number of radio wave absorbers required for construction is reduced, and the time required for the radio wave absorber assembly process and the radio wave absorber attachment process can be further reduced. . On the other hand, by setting the length of one side to 70 cm or less, the size of the radio wave absorber can be made small, and when the radio wave absorber is attached to the wall or ceiling surface of the anechoic chamber, Handling is improved.

本発明の電波吸収体は、電波吸収性能を有する電波吸収体用シート材から構成されることが好ましい。すなわち、第一の電波吸収体部材の台形面Ａ、Ｂ、ＣおよびＤ並びに第二の電波吸収部材の四角形面ＥおよびＦが電波吸収体用シートから構成されることが好ましい。なお、電波吸収体が電波吸収体用シート材から構成される中空体である場合、その組み立て性を向上させる観点から、第一の電波吸収体部材の底部には、電波吸収体用シート材が実質的に存在しないか、部分的に存在しない形状も採用できる。本発明の電波吸収体を上記のシート材で構成されるものとすることで、電波吸収体の内部を中空とすることができ、カーボンやグラファイト等を含有した内部が中実の発泡ウレタンで構成される電波吸収体などに比べ、軽量で施工性が良く、輸送や保管が容易となる。なお、本発明の電波吸収体は、電波吸収性能を有する電波吸収体用シート材のみから構成されていてもよいし、本発明の効果を阻害しない範囲において電波吸収体用シート材以外の部材を有していてもよい。   The radio wave absorber of the present invention is preferably composed of a radio wave absorber sheet material having radio wave absorption performance. That is, it is preferable that the trapezoidal surfaces A, B, C, and D of the first radio wave absorber member and the square surfaces E and F of the second radio wave absorber member are formed of the radio wave absorber sheet. In the case where the radio wave absorber is a hollow body made of a radio wave absorber sheet material, from the viewpoint of improving its assemblability, the bottom of the first radio wave absorber member has a radio wave absorber sheet material. A shape that does not substantially exist or does not exist partially can be employed. By making the radio wave absorber of the present invention composed of the above sheet material, the interior of the radio wave absorber can be made hollow, and the inside containing carbon, graphite or the like is made of solid foamed urethane Compared to a radio wave absorber or the like, it is light and has good workability, and is easy to transport and store. The radio wave absorber of the present invention may be composed only of a radio wave absorber sheet material having radio wave absorption performance, or a member other than the radio wave absorber sheet material within a range that does not impair the effects of the present invention. You may have.

また、電波吸収体の内部を中空とすることができ、カーボンやグラファイト等を含有した内部が中実の発泡ウレタンで構成される電波吸収体などに比べ、軽量で施工性が良く、輸送や保管が容易となるとの観点から、第二に電波吸収体部材がさらに三角形面ＧおよびＨを有する場合や、底部に底面が配される場合には、三角形面ＧおよびＨや底面が、電波吸収体用シートから構成されることが好ましい。   In addition, the interior of the wave absorber can be made hollow, and it is lighter and has better workability, transportation and storage compared to a wave absorber made of solid foamed urethane containing carbon or graphite. From the viewpoint of facilitating the operation, secondly, when the radio wave absorber member further has triangular surfaces G and H, or when the bottom surface is arranged at the bottom, the triangular surfaces G and H and the bottom surface are the radio wave absorbers. It is preferable that it is comprised from the sheet for use.

電波吸収性能を有する電波吸収体用シート材としては、電波吸収体用シート材に電波吸収性能を付与するための材料を含有する電波吸収体用シート材が挙げられる。上記の電波吸収体用シート材に用いる電波吸収体用シート材に電波吸収性能を付与するための材料としては、導電性材料や磁性材料が挙げられるが、低コスト化や軽量化、基材に均一に分散させやすいといった点から導電性材料を用いることが好ましい。導電性材料の中でも、導電性短繊維を用いることがより好ましい。導電性短繊維はアスペクト比が大きいので、繊維同士が接触しやすく、粉体に比べて少量でも効果的に電波吸収体用シート材に電波吸収性能を付与することができる。また、導電性短繊維の中でも、炭素繊維は、繊維自体が剛直であり基材内に配向させやすいこと、長期間の使用においてほとんど性能の変化がないことから、更に好ましい。   Examples of the radio wave absorber sheet material having radio wave absorbing performance include a radio wave absorber sheet material containing a material for imparting radio wave absorbing performance to the radio wave absorber sheet material. Examples of the material for imparting radio wave absorption performance to the radio wave absorber sheet material used in the above radio wave absorber sheet material include conductive materials and magnetic materials. It is preferable to use a conductive material because it can be easily dispersed uniformly. Among conductive materials, it is more preferable to use conductive short fibers. Since the conductive short fibers have a large aspect ratio, the fibers are easily brought into contact with each other, and the radio wave absorber sheet material can be effectively imparted with radio wave absorbing performance even in a small amount as compared with the powder. Among conductive short fibers, carbon fibers are more preferable because the fibers themselves are rigid and easy to be oriented in the base material, and there is almost no change in performance over a long period of use.

また、上記の電波吸収体用シート材の形態としては、樹脂膜、フィルム、不織布、織物、編物、紙、紙を基材とした段ボール、樹脂板または発泡ボートなどがある。また、上記の電波吸収体用シート材の形態は、折り曲げて中空立体形状の電波吸収体とするため、折り曲げ加工のやり易さの点からフィルムや不織布、織物、編物、紙、または、紙を基材とした段ボールとすることが好ましい。   Moreover, as a form of said sheet | seat material for electromagnetic wave absorbers, there are a resin film, a film, a nonwoven fabric, a woven fabric, a knitted fabric, paper, a corrugated cardboard based on paper, a resin plate, or a foam boat. In addition, the above-mentioned sheet material for the wave absorber is folded into a hollow three-dimensional wave absorber, so that film, non-woven fabric, woven fabric, knitted fabric, paper, or paper is used from the viewpoint of easy folding. It is preferable to use corrugated cardboard as a base material.

また、上記の電波吸収体用シート材は、例えば、フィルムなどを構成する材料に導電性材料などを添加し、それをフィルムなどの形態にしたものであってもよいし、導電性材料などを含有した樹脂を、導電性材料や磁性材料を含有しないフィルムなどにコーティングしたものであってもよいし、また、導電性材料などを含有したフィルムなどを、導電性材料や磁性材料を含有しないフィルムなどに積層したものであってもよい。当然、導電性材料などを含有したフィルムなどを、導電性材料や磁性材料を含有しない樹脂板などに積層したものであってもよい。   In addition, the above-described electromagnetic wave absorber sheet material may be obtained by adding a conductive material to a material constituting a film and the like, and forming the film into a film or the like. A film containing no conductive material or magnetic material may be coated with the contained resin, or a film containing a conductive material or the like may be coated with a film containing no conductive material or magnetic material. It may be laminated on the like. Of course, a film containing a conductive material or the like may be laminated on a resin plate that does not contain a conductive material or a magnetic material.

導電性材料や磁性材料を含有させる基材の材料としては、上記の電波吸収体用シート材の形態が、樹脂膜やフィルムである場合には、天然ゴム、イソプレンゴム、ブタジエンゴム、スチレンブタジエンゴム等のジエン系ゴムや、ブチルゴム、エチレンプロピレンゴム、ウレタンゴム、シリコーンゴム等の非ジエン系ゴム等のゴム材料や、ポリオレフィン樹脂、ポリアミド樹脂、ポリエステル樹脂、ポリエーテル樹脂、ポリイミド樹脂、ポリウレタン樹脂、ポリシロキサン樹脂、フェノール樹脂、エポキシ樹脂、アクリル樹脂、ユリア樹脂、メラミン樹脂、フッ素樹脂、ポリ塩化ビニル樹脂、ポリフェニレンサルファイド樹脂等の樹脂材料が挙げられる。   As a base material containing a conductive material or a magnetic material, natural rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber when the above-mentioned sheet material for radio wave absorber is a resin film or film Rubber materials such as diene rubber such as butyl rubber, ethylene propylene rubber, urethane rubber and silicone rubber, polyolefin resin, polyamide resin, polyester resin, polyether resin, polyimide resin, polyurethane resin, poly Resin materials such as siloxane resin, phenol resin, epoxy resin, acrylic resin, urea resin, melamine resin, fluorine resin, polyvinyl chloride resin, and polyphenylene sulfide resin can be used.

また、上記の電波吸収体用シート材の形態が、織物、編物、不織布、または、紙等の繊維を主体とする構造体の場合には、導電性材料や磁性材料を含有させる基材の材料としては、ガラス繊維やセラミック繊維等の無機繊維、合成繊維、綿、麻、ウール、木材パルプといった天然繊維や、レーヨン等の半合成繊維が挙げられる。更に、合成繊維を形成するポリマーとしては、ポリエチレンテレフタレート、ポリブチレンテレフタレート、ポリ乳酸、およびそれらのポリエステルの酸成分にイソフタル酸、５−ナトリウムスルホイソフタル酸、アジピン酸等を共重合した共重合ポリエステル等のポリエステルや、ナイロン６、ナイロン６６、ナイロン１２、ナイロン４６、ナイロン６とナイロン６６とを共重合した共重合ポリアミド等のポリアミドや、ポリビニルアルコールや、芳香族ポリアミドや、ポリエーテルエーテルケトンや、ポリパラフェニレンベンゾビスオキサゾールや、ポリフェニレンサルファイドや、ポリエチレンや、ポリプロピレン等を挙げることができる。難燃性向上の観点からは、上記に挙げた基材の材料のなかでも、ガラス繊維、芳香族ポリアミド繊維、ポリエーテルエーテルケトン繊維、ポリパラフェニレンベンゾビスオキサゾール繊維、ポリフェニレンサルファイド繊維等を用いることが好ましい。また、水酸化アルミニウムや水酸化マグネシウム等の無機粉末を基材の材料に添加することにより、難燃性を向上させることもできる。   In addition, in the case where the form of the sheet material for the radio wave absorber is a woven fabric, a knitted fabric, a non-woven fabric, or a structure mainly composed of fibers such as paper, a base material containing a conductive material or a magnetic material is used. Examples thereof include inorganic fibers such as glass fibers and ceramic fibers, synthetic fibers, natural fibers such as cotton, hemp, wool, and wood pulp, and semi-synthetic fibers such as rayon. Furthermore, examples of the polymer forming the synthetic fiber include polyethylene terephthalate, polybutylene terephthalate, polylactic acid, and copolymer polyester obtained by copolymerizing the acid component of those polyesters with isophthalic acid, 5-sodium sulfoisophthalic acid, adipic acid, and the like. Polyester, nylon 6, nylon 66, nylon 12, nylon 46, polyamide such as copolymerized polyamide obtained by copolymerizing nylon 6 and nylon 66, polyvinyl alcohol, aromatic polyamide, polyether ether ketone, Examples include paraphenylene benzobisoxazole, polyphenylene sulfide, polyethylene, and polypropylene. From the viewpoint of improving flame retardancy, glass fibers, aromatic polyamide fibers, polyether ether ketone fibers, polyparaphenylene benzobisoxazole fibers, polyphenylene sulfide fibers, etc. should be used among the above-mentioned base material materials. Is preferred. Moreover, a flame retardance can also be improved by adding inorganic powders, such as aluminum hydroxide and magnesium hydroxide, to the material of a base material.

上記の電波吸収体用シート材の形態の中でも、段ボールは電波吸収体用シート材中に空隙を有するため軽量であることに加え、立体形状とするのに十分なシート強度を有しているため、上記の電波吸収体用シート材の形態としては、特に好ましい。また、上記の電波吸収体用シート材の形態を段ボールとする場合には、生産性の点から、導電性材料や磁性材料を含有した紙を製造し、これをコルゲート加工によって段ボール状に加工した構成が好ましく使用される。一般的に段ボールは波型に加工された中芯紙と、上下面のライナー紙の３枚の紙で構成されるが、３枚の紙いずれにも導電性材料や磁性材料を含有しても良いし、３枚のうちいずれか１枚、もしくは２枚だけ含有しても良い。１枚だけに導電性材料や磁性材料を含有した紙を用いる場合には中芯紙に用いるのが好ましく、２枚だけ含有させる場合は、上下面のライナー紙に用いるのが好ましい。   Among the forms of the electromagnetic wave absorber sheet material described above, the corrugated cardboard is light in weight because it has voids in the electromagnetic wave absorber sheet material, and has sufficient sheet strength to form a three-dimensional shape. The form of the above-mentioned electromagnetic wave absorber sheet material is particularly preferable. In addition, when the sheet material for the radio wave absorber is made of corrugated cardboard, from the viewpoint of productivity, a paper containing a conductive material or a magnetic material is manufactured and processed into a corrugated cardboard by corrugating. A configuration is preferably used. Generally, corrugated cardboard is composed of three sheets of corrugated core paper and upper and lower liner sheets, but any of the three sheets may contain conductive or magnetic materials. It is good, and any one of the three or only two may be contained. When paper containing a conductive material or magnetic material is used for only one sheet, it is preferably used for a core paper, and when only two sheets are used, it is preferably used for upper and lower liner paper.

上記の電波吸収体用シート材の形態が樹脂膜、フィルム、不織布、織物、編物、紙または紙を基材とした段ボールである場合、その厚みは０．０５ｍｍ以上５ｍｍ以下の範囲にあることが好ましい。厚みをこの範囲とすることにより、中空立体形状の電波吸収体としたときに良好な強度が得られるとともに、折り曲げ加工が容易にできるためである。   When the above-mentioned sheet material for radio wave absorber is a corrugated cardboard based on resin film, film, nonwoven fabric, woven fabric, knitted fabric, paper or paper, its thickness may be in the range of 0.05 mm or more and 5 mm or less. preferable. This is because, by setting the thickness within this range, good strength can be obtained and a bending process can be easily performed when a hollow three-dimensional electromagnetic wave absorber is obtained.

上記の電波吸収体用シート材の形態が樹脂板または発泡ボードである場合には、その厚みは１ｍｍ以上３０ｍｍ以下であることが好ましく、下限しては２ｍｍ以上がより好ましく、上限としては１０ｍｍ以下がより好ましい。厚みをこの範囲とすることにより、特に強度の要求される電波吸収体を必要とする場合にも対応可能な良好な強度が得られる。   When the form of the sheet material for a radio wave absorber is a resin plate or a foam board, the thickness is preferably 1 mm or more and 30 mm or less, more preferably 2 mm or more as a lower limit, and 10 mm or less as an upper limit. Is more preferable. By setting the thickness within this range, it is possible to obtain a satisfactory strength that can be used even when a radio wave absorber that particularly requires strength is required.

本発明の電波吸収体用シート材の３ＧＨｚにおける複素比誘電率は、実部εｒ’が７以上１８以下、かつ、虚部εｒ”が４以上１５以下の範囲にあることが好ましい。特に好ましくは、実部εｒ’の下限は８以上であることがより好ましく、その上限は１６以下であることがより好ましい。また、虚部εｒ”の下限は５以上であることがより好ましく、その上限は１３以下であることがより好ましい。このような範囲の複素比誘電率の電波吸収体用シート材を組み立て、上記の形状とすることにより、高度な吸収性能、特に１ＧＨｚ〜３ＧＨｚの高周波帯域の電波に対し優れた吸収性能を有する電波吸収体を得ることができる。一般的に、電波暗室では、数十〜数百ＭＨｚの低周波帯域の吸収を担うフェライトタイルと、ＧＨｚの高周波帯域の吸収を担うピラミッド型やクサビ型吸収体等の立体型吸収体とが組み合わせて用いられる。立体型吸収体の複素比誘電率が高すぎると、低周波帯域の反射が大きくなりフェライトタイルでの電波吸収性能が低下する。一方、複素比誘電率が低すぎると立体型吸収体において高周波帯域の電波を十分に吸収できないといった傾向にある。本発明の電波吸収体用シート材の複素比誘電率を上述の範囲とすることで、十分な電波吸収性能を実現できるようになるため、好ましい。   The complex relative permittivity at 3 GHz of the sheet material for radio wave absorber of the present invention is preferably such that the real part εr ′ is in the range of 7 to 18 and the imaginary part εr ″ is in the range of 4 to 15. Particularly preferably. The lower limit of the real part εr ′ is more preferably 8 or more, and the upper limit thereof is more preferably 16. The lower limit of the imaginary part εr ″ is more preferably 5 or more, and the upper limit thereof is More preferably, it is 13 or less. By assembling a sheet material for a radio wave absorber having a complex dielectric constant in such a range and having the above shape, a radio wave having high absorption performance, particularly excellent radio wave performance in a high frequency band of 1 GHz to 3 GHz. An absorber can be obtained. Generally, in an anechoic chamber, a ferrite tile that is responsible for absorption in the low frequency band of several tens to several hundreds of MHz is combined with a three-dimensional type absorber such as a pyramid type or wedge type absorber that is responsible for absorption in the high frequency band of GHz. Used. If the complex relative permittivity of the three-dimensional absorber is too high, reflection in the low frequency band is increased and the radio wave absorption performance of the ferrite tile is lowered. On the other hand, if the complex dielectric constant is too low, the three-dimensional absorber tends to be unable to sufficiently absorb radio waves in the high frequency band. By setting the complex dielectric constant of the sheet material for a radio wave absorber of the present invention within the above range, it is preferable because sufficient radio wave absorption performance can be realized.

本実施例で用いた測定法を後述する。   The measurement method used in this example will be described later.

（１）電波吸収体用シート材の複素比誘電率
縦３０ｃｍ×横３０ｃｍ×厚み５ｍｍのアルミニウム板の上面に、アルミニウム板と同一サイズかつ同一形状の発泡倍率７０倍の発泡スチロール製スペーサー（厚み１４ｍｍ）を上載し、このスペーサーの上にさらにアルミニウム板と同一サイズの電波吸収体用シート材を上載し、発泡スチロール製スペーサーの中心点（発泡スチロール製スペーサーの上記アルミニウム板側の面の反対側の面上かつ発泡スチロール製スペーサーの２本の対角線の交点）から１．４ｍ離れた直上の位置に送信および受信アンテナを電波の入射角度が７°となるようにセットし、２〜４ＧＨｚの周波数範囲の電波をサンプルに入射し、ベクトルネットワークアナライザ（機種：Ｎ５２３０、アジレントテクノロジー社製）を用いて、入力インピーダンスを測定した。その後、電波吸収体用シート材を取り除き、上記と同様に電波吸収体用シート材を取り除いた状態の入力インピーダンスを測定し、電波吸収体用シート材がある場合とない場合との入力インピーダンスの差から、電波吸収体用シート材の複素比誘電率を算出、周波数３ＧＨｚ時の複素比誘電率の実部εｒ’と虚部εｒ”を読み取った。測定は異なる電波吸収体用シート材を用いＮ＝３で、それぞれの電波吸収体用シート材について、その任意の一辺と平行方向、および、その一辺と垂直方向の複素比誘電率の実部εｒ’と虚部εｒ”を測定し、得られた複素比誘電率の実部εｒ’と虚部εｒ”の各６つの測定値の平均値を複素比誘電率の実部εｒ’と虚部εｒ”とした。 (1) Complex relative dielectric constant of sheet material for radio wave absorber On the upper surface of an aluminum plate having a length of 30 cm, a width of 30 cm and a thickness of 5 mm, a styrofoam spacer (thickness: 14 mm) having the same size and shape as the aluminum plate and a foaming ratio of 70 times On top of this spacer, a sheet material for a radio wave absorber having the same size as the aluminum plate is further placed, and the center point of the polystyrene foam spacer (on the surface opposite to the aluminum plate side surface of the polystyrene foam spacer and Set the transmitting and receiving antennas to a position just 1.4m away from the intersection of two diagonal lines of polystyrene foam spacers) so that the incident angle of radio waves is 7 °, and sample radio waves in the frequency range of 2 to 4 GHz. The vector network analyzer (model: N5230, manufactured by Agilent Technologies) ) Was used to measure the input impedance. After that, remove the wave absorber sheet material and measure the input impedance with the wave absorber sheet material removed as above, and the difference between the input impedance with and without the wave absorber sheet material. From this, the complex relative permittivity of the sheet material for the radio wave absorber was calculated, and the real part εr ′ and the imaginary part εr ″ of the complex relative dielectric constant at the frequency of 3 GHz were read. = 3, for each radio wave absorber sheet material, the real part εr ′ and the imaginary part εr ″ of the complex relative permittivity in the direction parallel to the one side and the direction perpendicular to the one side are obtained. The average values of the six measured values of the real part εr ′ and the imaginary part εr ″ of the complex relative dielectric constant were defined as the real part εr ′ and the imaginary part εr ″ of the complex relative dielectric constant.

（２）電波吸収体の電波吸収量
縦６０ｃｍ×横６０ｃｍ×厚み５ｍｍのアルミニウム板を、正方形状に４枚並べ、縦１２０ｃｍ×横１２０ｃｍとなるように配置した。この中心点（縦１２０ｃｍ×横１２０ｃｍのアルミニウム板の一方の面の表面上かつその２本の対角点の交点）から２．７ｍ離れた直上の位置に送信および受信アンテナを電波の入射角度が７°となるようにセットし、１〜３ＧＨｚの周波数範囲の電波をアルミニウム板に入射し、アルミニウム板の反射レベルをベクトルネットワークアナライザ（機種：Ｎ５２３０、アジレントテクノロジー社製）を用いて測定した。次に、このアルミニウム板の上に、底部が６０ｃｍ×６０ｃｍのサイズの電波吸収体４つを、上記のアルミニウム板の一方の面全体を覆うように置き、その電波吸収体の反射レベルを測定した。これらの測定値から次式により電波吸収体の電波吸収量（反射減衰量）を求め、１〜３ＧＨｚにおける最小値と最大値を読み取った。
電波吸収量（ｄＢ）＝アルミニウム板の反射レベル（ｄＢ）−電波吸収体の反射レベル（ｄＢ）
（実施例１）
（電波吸収体用シート材）
平均繊維長３ｍｍのポリアクリロニトリル系炭素繊維（東レ株式会社製“トレカ”（登録商標））、平均繊維長４ｍｍのガラス繊維、木質パルプ、平均繊維長３ｍｍの芯鞘型熱融着ポリエステル短繊維（東レ株式会社製“サフメット”（登録商標））、水酸化アルミニウムを、それぞれ１質量％、１９質量％、７質量％、３質量％、７０質量％の割合で水に混合してスラリーとし、そのスラリーを平面に流し込み、脱水、乾燥し、厚み１３０μｍ、坪量１００ｇ／ｍ^２の難燃紙Ｉを得た。 (2) Radio wave absorption amount of radio wave absorber Four aluminum plates having a length of 60 cm, a width of 60 cm, and a thickness of 5 mm were arranged in a square shape so as to be 120 cm long and 120 cm wide. The incident angle of the radio wave is set between the transmitting and receiving antennas at a position 2.7 m away from the center point (on the surface of one surface of an aluminum plate 120 cm long × 120 cm wide and the intersection of the two diagonal points). It set so that it might become 7 degrees, the electromagnetic wave of the frequency range of 1-3 GHz was injected into the aluminum plate, and the reflection level of the aluminum plate was measured using the vector network analyzer (model: N5230, Agilent Technologies). Next, on the aluminum plate, four wave absorbers having a size of 60 cm × 60 cm at the bottom were placed so as to cover the entire surface of the aluminum plate, and the reflection level of the wave absorber was measured. . From these measured values, the radio wave absorption amount (reflection attenuation amount) of the radio wave absorber was obtained by the following equation, and the minimum value and the maximum value at 1 to 3 GHz were read.
Radio wave absorption (dB) = reflection level (dB) of aluminum plate−reflection level (dB) of radio wave absorber
Example 1
(Radio wave absorber sheet material)
Polyacrylonitrile-based carbon fiber with an average fiber length of 3 mm (“Torayca” (registered trademark) manufactured by Toray Industries, Inc.), glass fiber with an average fiber length of 4 mm, wood pulp, core-sheath type heat-sealable polyester short fiber with an average fiber length of 3 mm ( “Safmet” (registered trademark) manufactured by Toray Industries, Inc.) and aluminum hydroxide were mixed in water at a ratio of 1% by mass, 19% by mass, 7% by mass, 3% by mass, and 70% by mass, respectively. The slurry was poured into a flat surface, dehydrated and dried to obtain flame retardant paper I having a thickness of 130 μm and a basis weight of 100 g / m ² .

同様にして、ポリアクリロニトリル系炭素繊維を除いた配合で、平均繊維長４ｍｍのガラス繊維の割合を２０質量％に変更し、上記と同一の方法で、厚み１３０μｍ、坪量１００ｇ／ｍ^２の難燃紙ＩＩを得た。 In the same manner, the ratio of the glass fiber having an average fiber length of 4 mm was changed to 20% by mass with the composition excluding the polyacrylonitrile-based carbon fiber, and the same method as described above, the thickness of 130 μm and the basis weight of 100 g / m ² was difficult. Fuel paper II was obtained.

続いて、前記難燃紙ＩＩを熱プレスロールで波形に加工し、段ボール３層構造の波状中芯部とし、その両側を平面状の難燃紙Ｉと貼り合わせることによって、厚み３．０ｍｍの段ボールシート材とした。   Subsequently, the flame retardant paper II is processed into a corrugated shape with a hot press roll to form a corrugated core portion having a corrugated cardboard three-layer structure, and both sides thereof are bonded to the planar flame retardant paper I to have a thickness of 3.0 mm. Corrugated sheet material was used.

この電波吸収体用シート材の、３ＧＨｚにおける複素比誘電率を測定した結果、実部εｒ’＝１１．３、虚部εｒ”＝６．５であった。   As a result of measuring the complex dielectric constant at 3 GHz of the sheet material for radio wave absorber, the real part εr ′ = 11.3 and the imaginary part εr ″ = 6.5.

（電波吸収体）
この電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６５．２°で、高さが３５．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも２７．７ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが４０．０ｃｍの電波吸収体を得た。 (Radio wave absorber)
This radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the trapezoidal surfaces A, B, C, and D, and the angle formed between the bottom and the trapezoidal surfaces A, B, C, and D (acute angle) ) Are 65.2 °, the height is 35.0 cm, the bottom is 60.0 × 60.0 cm square, and the diagonal length of the bottom is 84.9 cm. A body member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: All were 27.7 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the kraft tape, and the electromagnetic wave absorber with a height of 40.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表１に示すが、１〜３ＧＨｚの周波数帯域において最小１９ｄＢ、最大３５ｄＢの高度な電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 1, and it was found that they had a high level of radio wave absorption of 19 dB minimum and 35 dB maximum in the frequency band of 1 to 3 GHz.

（実施例２）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６５．２°で、高さが４０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも２３．２ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが４５．０ｃｍの電波吸収体を得た。 (Example 2)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square pyramid-shaped first of which the angle (acute angle) is 65.2 °, the height is 40.0 cm, the bottom is 60.0 × 60.0 cm square, and the diagonal of the bottom is 84.9 cm. A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: Both were 23.2 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the kraft tape, and the electromagnetic wave absorber with a height of 45.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表１に示すが、１〜３ＧＨｚの周波数帯域において最小１９ｄＢ、最大３６ｄＢの高度な電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 1. It was found that the radio wave absorption amount was a minimum of 19 dB and a maximum of 36 dB in the frequency band of 1 to 3 GHz.

（実施例３）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６５．２°で、高さが４５．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも１９．４ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５０．０ｃｍの電波吸収体を得た。 Example 3
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square pyramid-shaped first with an angle (acute angle) of 65.2 °, a height of 45.0 cm, a bottom of 60.0 × 60.0 cm, and a diagonal of the bottom of 84.9 cm A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: Both were 19.4 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. Then, the contacting sides were joined with craft tape to obtain a radio wave absorber having a height of 50.0 cm.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表１に示すが、１〜３ＧＨｚの周波数帯域において最小２１ｄＢ、最大３８ｄＢの高度な電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 1, and it was found that they have a high level of radio wave absorption of a minimum of 21 dB and a maximum of 38 dB in the frequency band of 1 to 3 GHz.

（実施例４）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６６．７°で、高さが４５．０ｃｍ、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも２１．６ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５０．０ｃｍの電波吸収体を得た。 Example 4
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. A first square wave frustum-shaped first wave absorber member having an angle (acute angle) of 66.7 °, a height of 45.0 cm, and a bottom diagonal length of 84.9 cm was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: Both were 21.6 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. Then, the contacting sides were joined with craft tape to obtain a radio wave absorber having a height of 50.0 cm.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表１に示すが、１〜３ＧＨｚの周波数帯域において最小１６ｄＢ、最大３３ｄＢの高度な電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 1, and it was found that they have a high level of radio wave absorption of 16 dB minimum and 33 dB maximum in the frequency band of 1 to 3 GHz.

（実施例５）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６８．０°で、高さが４５．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも２３．４ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５０．０ｃｍの電波吸収体を得た。 (Example 5)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square pyramid-shaped first with an angle (acute angle) of 68.0 °, a height of 45.0 cm, a bottom of 60.0 × 60.0 cm square, and a bottom diagonal of 84.9 cm A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: All were 23.4 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. Then, the contacting sides were joined with craft tape to obtain a radio wave absorber having a height of 50.0 cm.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表１に示すが、１〜３ＧＨｚの周波数帯域において最小１５ｄＢ、最大２９ｄＢの高度な電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 1, and it was found that they have a high radio wave absorption amount of 15 dB minimum and 29 dB maximum in the frequency band of 1 to 3 GHz.

（実施例６）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６４．３°で、高さが５０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも１１．８ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５５．０ｃｍの電波吸収体を得た。 (Example 6)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square pyramid-shaped first with an angle (acute angle) of 64.3 °, a height of 50.0 cm, a bottom of 60.0 × 60.0 cm, and a diagonal of the bottom of 84.9 cm A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: All were 11.8 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the craft tape, and the electromagnetic wave absorber with a height of 55.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表１に示すが、１〜３ＧＨｚの周波数帯域において最小１７ｄＢ、最大３５ｄＢの高度な電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 1, and it was found that they have a high radio wave absorption amount of 17 dB minimum and 35 dB maximum in the frequency band of 1 to 3 GHz.

（実施例７）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６５．２°で、高さが５０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも１３．８ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５５．０ｃｍの電波吸収体を得た。 (Example 7)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square pyramid-shaped first with an angle (acute angle) of 65.2 °, a height of 50.0 cm, a bottom of 60.0 × 60.0 cm, and a diagonal length of 84.9 cm at the bottom. A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: All were 13.8 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the craft tape, and the electromagnetic wave absorber with a height of 55.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表２に示すが、１〜３ＧＨｚの周波数帯域において最小２５ｄＢ、最大４１ｄＢの高度な電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 2, and it was found that they have a high level of radio wave absorption of 25 dB minimum and 41 dB maximum in the frequency band of 1 to 3 GHz.

（実施例８）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６６．７°で、高さが５０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも１７．２ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５５．０ｃｍの電波吸収体を得た。 (Example 8)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first of the regular square frustum shape whose angles (acute angles) are 66.7 °, the height is 50.0 cm, the bottom is 60.0 × 60.0 cm square, and the diagonal of the bottom is 84.9 cm. A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: Both were 17.2 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. Then, the contacting sides were joined with kraft tape to obtain a radio wave absorber having a height of 55.0 cm.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表２に示すが、１〜３ＧＨｚの周波数帯域において最小１５ｄＢ、最大３７ｄＢの高度な電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 2, and it was found that the radio wave absorption amount was a minimum of 15 dB and a maximum of 37 dB in the frequency band of 1 to 3 GHz.

（実施例９）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６８．０°で、高さが５０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、斜面Ｅ〜Ｈの底辺の長さは、いずれも１９．４ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５５．０ｃｍの電波吸収体を得た。 Example 9
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first of the square square frustum shape in which the angles (acute angles) are all 68.0 °, the height is 50.0 cm, the bottom is 60.0 × 60.0 cm square, and the length of the diagonal of the bottom is 84.9 cm. A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. In addition, all the lengths of the bottom sides of the slopes E to H were 19.4 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the craft tape, and the electromagnetic wave absorber with a height of 55.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表２に示すが、１〜３ＧＨｚの周波数帯域において最小１５ｄＢ、最大３２ｄＢの高度な電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 2, and it was found that they have a high radio wave absorption amount of 15 dB minimum and 32 dB maximum in the frequency band of 1 to 3 GHz.

（実施例１０）
（電波吸収体用シート材）
実施例１と同様にして、平均繊維長３ｍｍのポリアクリロニトリル系炭素繊維（東レ株式会社製“トレカ”（登録商標））、平均繊維長４ｍｍのガラス繊維を、それぞれ０．６質量％、１９．４質量％に変更した以外は、難燃紙Ｉと同様にして、厚み１３０μｍ、坪量１００ｇ／ｍ^２の難燃紙ＩＩＩを得た。 (Example 10)
(Radio wave absorber sheet material)
In the same manner as in Example 1, polyacrylonitrile-based carbon fiber having an average fiber length of 3 mm (“Torayca” (registered trademark) manufactured by Toray Industries, Inc.) and glass fiber having an average fiber length of 4 mm were each 0.6 mass% and 19. A flame retardant paper III having a thickness of 130 μm and a basis weight of 100 g / m ² was obtained in the same manner as the flame retardant paper I except that the content was changed to 4% by mass.

続いて、実施例１で用いた難燃紙ＩＩを熱プレスロールで波形に加工し、段ボール３層構造の波状中芯部とし、その両側を平面状の難燃紙ＩＩＩと貼り合わせることによって、厚み３．０ｍｍの段ボールシート材とした。   Subsequently, by processing the flame retardant paper II used in Example 1 into a corrugated shape with a hot press roll, forming a corrugated core portion of a corrugated cardboard three-layer structure, and laminating both sides thereof with the planar flame retardant paper III, A corrugated sheet material having a thickness of 3.0 mm was used.

この電波吸収体用シート材の、３ＧＨｚにおける複素比誘電率を測定した結果、実部εｒ’＝６．０、虚部εｒ”＝３．５であった。   As a result of measuring the complex relative dielectric constant at 3 GHz of the sheet material for radio wave absorber, the real part εr ′ = 6.0 and the imaginary part εr ″ = 3.5.

（電波吸収体）
上記の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６５．２°で、高さが５０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも１３．８ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５５．０ｃｍの電波吸収体を得た。 (Radio wave absorber)
The above-mentioned electromagnetic wave absorber sheet material is cut, bent, and craft tape is attached to the sides of the trapezoidal surfaces A, B, C and D, and the angle formed between the bottom and the trapezoidal surfaces A, B, C and D ( A first square-wave frustum-shaped first radio wave having an acute angle of 65.2 °, a height of 50.0 cm, a bottom of 60.0 × 60.0 cm, and a diagonal length of 84.9 cm at the bottom. An absorbent member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: All were 13.8 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the craft tape, and the electromagnetic wave absorber with a height of 55.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表２に示すが、１〜３ＧＨｚの周波数帯域において最小１４ｄＢ、最大２７ｄＢの吸収量を有しており、他の実施例に比べやや劣るが、高い電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 2, and have a minimum 14 dB and a maximum 27 dB absorption in the frequency band of 1 to 3 GHz, which is slightly inferior to the other examples, but has a high radio wave absorption. all right.

（実施例１１）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６５．２°で、高さが５５．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも９．２ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが６０．０ｃｍの電波吸収体を得た。 (Example 11)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. First of the square pyramid shape with an angle (acute angle) of 65.2 °, a height of 55.0 cm, a bottom of 60.0 × 60.0 cm square, and a diagonal length of the bottom of 84.9 cm. A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: Both were 9.2 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the craft tape, and the electromagnetic wave absorber with a height of 60.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表２に示すが、１〜３ＧＨｚの周波数帯域において最小２２ｄＢ、最大３９ｄＢの高度な電波吸収量を有していることがわかった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 2, and it was found that they have a high level of radio wave absorption of a minimum of 22 dB and a maximum of 39 dB in the frequency band of 1 to 3 GHz.

（実施例１２）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６５．２°で、高さが６４．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが０．５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも０．９ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが６４．５ｃｍの電波吸収体を得た。 (Example 12)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square-frustum-shaped first of which the angle (acute angle) is 65.2 °, the height is 64.0 cm, the bottom is 60.0 × 60.0 cm square, and the diagonal of the bottom is 84.9 cm. A radio wave absorber member was obtained. Next, the sheet material for the radio wave absorber is cut, bent, and craft tape is attached to the sides of the square surfaces E and F and the triangular surfaces G and H, so that the height is 0.5 cm. A second wave absorber member was created. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: Both were 0.9 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. Then, the contacting sides were joined with craft tape to obtain a radio wave absorber having a height of 64.5 cm.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表２に示すが、１〜３ＧＨｚの周波数帯域において最小１９ｄＢ、最大３８ｄＢの高度な電波吸収量を有していることがわかった。
（実施例１３）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６５．２°で、高さが４０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げて、５ｃｍの第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺および四角形面Ｆの四角形面Ｅと共有する辺に対向する辺の長さは共に２３．２ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺および台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが４５．０ｃｍの電波吸収体を得た。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 2, and it was found that the radio wave absorption amount was a minimum of 19 dB and a maximum of 38 dB in the frequency band of 1 to 3 GHz.
(Example 13)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square pyramid-shaped first of which the angle (acute angle) is 65.2 °, the height is 40.0 cm, the bottom is 60.0 × 60.0 cm square, and the diagonal of the bottom is 84.9 cm. A radio wave absorber member was obtained. Next, the sheet material for a radio wave absorber was cut and bent to prepare a second radio wave absorber member of 5 cm. The length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F and the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E were 23.2 cm. Next, the side facing the side shared with the quadrangular surface F of the trapezoidal surface A and the side of the quadrangular surface E and the side facing the side of the trapezoidal surface B and the side shared with the quadrangular surface E of the quadrangular surface F are: The second radio wave absorber member was placed on the first radio wave absorber member so as to be in contact with each other, and the sides to be in contact were joined with craft tape to obtain a radio wave absorber having a height of 45.0 cm. .

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表２に示すが、１〜３ＧＨｚの周波数帯域において最小１９ｄＢ、最大３６ｄＢの高度な電波吸収量を有していることがわかった。
（比較例１）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６３．４°で、高さが４５．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも１５．０ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５０．０ｃｍの電波吸収体を得た。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 2, and it was found that they have a high level of radio wave absorption of 19 dB minimum and 36 dB maximum in the frequency band of 1 to 3 GHz.
(Comparative Example 1)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square pyramid-shaped first with an angle (acute angle) of 63.4 °, a height of 45.0 cm, a bottom of 60.0 × 60.0 cm, and a diagonal length of 84.9 cm at the bottom. A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: All were 15.0 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. Then, the contacting sides were joined with craft tape to obtain a radio wave absorber having a height of 50.0 cm.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表３に示すが、１〜３ＧＨｚの周波数帯域において最小１１ｄＢ、最大２５ｄＢの電波吸収量であり、実施例の電波吸収体に比べ電波吸収性能に劣るものであった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 3, and the radio wave absorption amount is a minimum of 11 dB and a maximum of 25 dB in the frequency band of 1 to 3 GHz, which is inferior to the radio wave absorber of the example.

（比較例２）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６３．４°で、高さが５０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも１０．０ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５５．０ｃｍの電波吸収体を得た。 (Comparative Example 2)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square pyramid-shaped first with an angle (acute angle) of 63.4 °, a height of 50.0 cm, a bottom of 60.0 × 60.0 cm, and a diagonal at the bottom of 84.9 cm A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: Both were 10.0 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the craft tape, and the electromagnetic wave absorber with a height of 55.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表３に示すが、１〜３ＧＨｚの周波数帯域において最小１０ｄＢ、最大２６ｄＢの電波吸収量であり、実施例の電波吸収体に比べ電波吸収性能に劣るものであった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 3, and the radio wave absorption amount is 10 dB minimum and 26 dB maximum in the frequency band of 1 to 3 GHz, which is inferior to the radio wave absorber of the example.

（比較例３）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６８．５°で、高さが４５．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも２４．４ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５０．０ｃｍの電波吸収体を得た。 (Comparative Example 3)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first of the square pyramid shape with an angle (acute angle) of 68.5 °, a height of 45.0 cm, a bottom of 60.0 × 60.0 cm, and a diagonal length of 84.9 cm at the bottom. A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: All were 24.4 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. Then, the contacting sides were joined with craft tape to obtain a radio wave absorber having a height of 50.0 cm.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表３に示すが、１〜３ＧＨｚの周波数帯域において最小１０ｄＢ、最大２４ｄＢの電波吸収量であり、実施例の電波吸収体に比べ電波吸収性能に劣るものであった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 3, and the radio wave absorption amount is 10 dB minimum and 24 dB maximum in the frequency band of 1 to 3 GHz, which is inferior to the radio wave absorber of the example.

（比較例４）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６８．５°で、高さが５０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも２０．５ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが５５．０ｃｍの電波吸収体を得た。 (Comparative Example 4)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square pyramid-shaped first with an angle (acute angle) of 68.5 °, a height of 50.0 cm, a bottom of 60.0 × 60.0 cm, and a diagonal length of 84.9 cm at the bottom. A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: Both were 20.5 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the craft tape, and the electromagnetic wave absorber with a height of 55.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表３に示すが、１〜３ＧＨｚの周波数帯域において最小１１ｄＢ、最大２６ｄＢの電波吸収量であり、実施例の電波吸収体に比べ電波吸収性能に劣るものであった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 3, and the radio wave absorption amount is a minimum of 11 dB and a maximum of 26 dB in the frequency band of 1 to 3 GHz, which is inferior to the radio wave absorber of the example.

（比較例５）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６５．２°で、高さが３０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも３２．４ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが３５．０ｃｍの電波吸収体を得た。 (Comparative Example 5)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first square pyramid-shaped first with an angle (acute angle) of 65.2 °, a height of 30.0 cm, a bottom of 60.0 × 60.0 cm, and a diagonal length of 84.9 cm at the bottom. A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: Both were 32.4 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the craft tape, and the electromagnetic wave absorber whose height is 35.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表３に示すが、１〜３ＧＨｚの周波数帯域において最小９ｄＢ、最大２５ｄＢの電波吸収量であり、実施例の電波吸収体に比べ電波吸収性能に劣るものであった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 3, and the radio wave absorption amount is 9 dB minimum and 25 dB maximum in the frequency band of 1 to 3 GHz, which is inferior to the radio wave absorber of the example.

（比較例６）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６５．２°で、高さが１１５．０ｃｍ、底部が１２０．０×１２０．０ｃｍ角、底部の対角線の長さが１６９．７ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも１３．８ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが１２０．０ｃｍの電波吸収体を得た。 (Comparative Example 6)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first of the square pyramid shape with an angle (acute angle) of 65.2 °, a height of 115.0 cm, a bottom of 120.0 × 120.0 cm, and a diagonal length of the bottom of 169.7 cm A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: All were 13.8 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. Then, the contacting sides were joined with kraft tape to obtain a radio wave absorber having a height of 120.0 cm.

この電波吸収体を４体用意し、縦２４０ｃｍ×横２４０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表３に示すが、１〜３ＧＨｚの周波数帯域において最小１２ｄＢ、最大２６ｄＢの電波吸収量であり、実施例の電波吸収体に比べ電波吸収性能に劣るものであった。 Four radio wave absorbers were prepared and placed on an aluminum plate having a length of 240 cm, a width of 240 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 3. The radio wave absorption amount is 12 dB minimum and 26 dB maximum in the frequency band of 1 to 3 GHz, which is inferior to the radio wave absorber of the example.

（比較例７）
実施例１の電波吸収体用シート材を裁断し、折り曲げ、台形面Ａ、Ｂ、ＣおよびＤの側辺部にクラフトテープを貼って、底部と台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６３．４°で、高さが３０．０ｃｍ、底部が６０．０×６０．０ｃｍ角、底部の対角線の長さが８４．９ｃｍの正四角錘台形状の第一の電波吸収体部材を得た。次に、上記の電波吸収体用シート材を裁断し、折り曲げ、四角形面ＥおよびＦ並びに三角形面ＧおよびＨの側辺部にクラフトテープを貼って、高さが５ｃｍの寄せ棟形状の第二の電波吸収体部材を作成した。なお、四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、三角形面Ｇの底辺および三角形面Ｈの底辺の長さは、いずれも３０．０ｃｍであった。次に、台形面Ａの上底と四角形面Ｅの四角形面Ｆと共有する辺に対向する辺、台形面Ｂの上底と四角形面Ｆの四角形面Ｅと共有する辺に対向する辺、台形面Ｃの上底と三角形面Ｇの底辺および台形面Ｄの上底と三角形面Ｈの底辺とがそれぞれ接するように、第一の電波吸収体部材の上に第二の電波吸収体部材を上載し、その接する辺をクラフトテープで接合して、高さが３５．０ｃｍの電波吸収体を得た。 (Comparative Example 7)
The radio wave absorber sheet material of Example 1 is cut, bent, and craft tape is attached to the side portions of the trapezoidal surfaces A, B, C, and D to form the bottom and the trapezoidal surfaces A, B, C, and D. The first of the square pyramid-shaped first with an angle (acute angle) of 63.4 °, a height of 30.0 cm, a bottom of 60.0 × 60.0 cm, and a diagonal of the bottom of 84.9 cm. A radio wave absorber member was obtained. Next, the radio wave absorber sheet material is cut, bent, and craft tape is pasted on the sides of the square surfaces E and F and the triangular surfaces G and H to form a second ridge-shaped second with a height of 5 cm. A radio wave absorber member was prepared. Note that the length of the side of the quadrangular surface E that faces the side that is shared with the quadrangular surface F, the length of the side of the quadrangular surface F that faces the side that is shared with the quadrangular surface E, the base of the triangular surface G, and the length of the base of the triangular surface H are: All were 30.0 cm. Next, the side facing the side shared with the quadrangle surface F of the trapezoid surface A and the square surface E, the side facing the side shared with the top surface of the trapezoid surface B and the square surface E of the square surface F, trapezoid The second radio wave absorber member is mounted on the first radio wave absorber member so that the upper base of the surface C and the base of the triangular surface G and the upper base of the trapezoidal surface D and the base of the triangular surface H are in contact with each other. And the side which touches was joined with the craft tape, and the electromagnetic wave absorber whose height is 35.0 cm was obtained.

この電波吸収体を４体用意し、縦１２０ｃｍ×横１２０ｃｍ×厚さ５ｍｍのアルミニウム板に上載して電波吸収量を測定した。
結果を表３に示すが、１〜３ＧＨｚの周波数帯域において最小７ｄＢ、最大１８ｄＢの電波吸収量であり、実施例の電波吸収体に比べ電波吸収性能に非常に劣るものであった。 Four of these radio wave absorbers were prepared and placed on an aluminum plate having a length of 120 cm, a width of 120 cm, and a thickness of 5 mm, and the amount of radio wave absorption was measured.
The results are shown in Table 3, and the radio wave absorption amount is 7 dB minimum and 18 dB maximum in the frequency band of 1 to 3 GHz, which is very inferior to the radio wave absorber of the example.

本発明の電波吸収体は、高度な電波吸収性能、特に１ＧＨｚ〜３ＧＨｚの高周波帯域の電波に対し優れた電波吸収性能を有し、たとえば、電波暗室等で好適に用いられる。   The radio wave absorber of the present invention has high radio wave absorption performance, particularly excellent radio wave absorption performance for radio waves in a high frequency band of 1 GHz to 3 GHz, and is preferably used in, for example, an anechoic chamber.

１：底部
２：台形面Ａ
４：四角形面Ｅ
６：電波吸収体用シート材
７：入射電波
８：第１の電波吸収体
９：第２の電波吸収体
１０：反射電波
１１：反射電波
１２：放射電波
１７：三角形面Ｇ
１８：台形面Ｂ
１９：台形面Ｃ
２０：台形面Ｄ
２１：四角形面Ｆ
２２：三角形面Ｈ
２３：第一の電波吸収体部材
２４：第二の電波吸収体部材
２６：底部と台形面Ａとの成す角度（鋭角）
２７：高さ
２８：高さ
Ｍ：入射角
Ｎ：反射角 1: Bottom 2: Trapezoidal surface A
4: Rectangular surface E
6: radio wave absorber sheet material 7: incident radio wave 8: first radio wave absorber 9: second radio wave absorber 10: reflected radio wave 11: reflected radio wave 12: radiated radio wave 17: triangular plane G
18: Trapezoid surface B
19: Trapezoid surface C
20: Trapezoid surface D
21: Rectangular surface F
22: Triangular plane H
23: First radio wave absorber member 24: Second radio wave absorber member 26: Angle formed by the bottom and the trapezoidal surface A (acute angle)
27: Height 28: Height M: Incident angle N: Reflection angle

Claims (5)

４つの台形面Ａ、Ｂ、ＣおよびＤを有する第一の電波吸収体部材であって、これら台形面Ａ、Ｂ、ＣおよびＤがこの順に隣り合い四角錐台形の斜面を構成するように配置された第一の電波吸収体部材と、
２つの四角形面ＥおよびＦを有する第二の電波吸収体部材であって、これら四角形面ＥおよびＦとで１辺を共有する２つの斜面を構成するように配置された第二の電波吸収体部材と、を有する電波吸収体であって、
前記四角形面Ｅの前記四角形面Ｆと共有する辺に対向する辺が、前記台形面Ａの上底と共有しており、
前記四角形面Ｆの前記四角形面Ｅと共有する辺に対向する辺が、前記台形面Ｃの上底と共有しており、
前記台形面Ａ、Ｂ、ＣおよびＤの各下底を通る平面と、前記台形面Ａ、Ｂ、ＣおよびＤとの成す角度（鋭角）がいずれも６４°以上６８°以下であり、
高さが４０ｃｍ以上１１０ｃｍ以下である、電波吸収体。 A first wave absorber member having four trapezoidal surfaces A, B, C, and D, and arranged such that these trapezoidal surfaces A, B, C, and D form a quadrangular pyramid-shaped slope that are adjacent in this order. A first electromagnetic wave absorber member,
A second wave absorber member having two rectangular surfaces E and F, the second wave absorber being arranged so as to form two inclined surfaces sharing one side with the rectangular surfaces E and F A radio wave absorber having a member,
The side opposite to the side shared with the square surface F of the square surface E is shared with the upper base of the trapezoidal surface A,
The side facing the side shared with the square surface E of the square surface F is shared with the upper base of the trapezoidal surface C,
The angle (acute angle) formed between the plane passing through the bottom of each of the trapezoidal surfaces A, B, C and D and the trapezoidal surfaces A, B, C and D is 64 ° or more and 68 ° or less,
A radio wave absorber having a height of 40 cm to 110 cm. 前記台形面Ａ、Ｂ、ＣおよびＤがいずれも同じ形状の等脚台形である、請求項１の電波吸収体。   The radio wave absorber according to claim 1, wherein each of the trapezoidal surfaces A, B, C, and D is an isosceles trapezoid having the same shape. 前記台形面Ａ、Ｂ、ＣおよびＤ並びに前記四角形面ＥおよびＦが、３ＧＨｚにおける複素比誘電率の実部εｒ’が７以上１８以下であり、虚部εｒ”が４以上１５以下である電波吸収体用シート材から構成された、請求項１または２の電波吸収体。   The trapezoidal surfaces A, B, C and D and the rectangular surfaces E and F are radio waves having a complex part permittivity real part εr ′ of 7 to 18 and an imaginary part εr ″ of 4 to 15 at 3 GHz. The radio wave absorber according to claim 1 or 2, comprising an absorber sheet material. 前記第二の電波吸収体部材が、前記四角形面ＥおよびＦのそれぞれと１辺を共有する三角形面Ｇ、並びに前記四角形面ＥおよびＦのそれぞれと１辺を共有する三角形面Ｈを有する寄棟形状またはくさび形状であり、
前記三角形面Ｇの前記四角形面ＥおよびＦと共有していない辺が、前記台形面Ｂの上底と共有しており、
前記三角形面Ｈの前記四角形面ＥおよびＦと共有していない辺が、前記台形面Ｄの上底と共有している、請求項１〜３のいずれかの電波吸収体。 The second radio wave absorber member has a triangular surface G that shares one side with each of the square surfaces E and F, and a triangular surface H that shares one side with each of the square surfaces E and F Shape or wedge shape,
Sides that are not shared with the rectangular surfaces E and F of the triangular surface G are shared with the upper base of the trapezoidal surface B,
The radio wave absorber according to any one of claims 1 to 3, wherein a side of the triangular surface H that is not shared with the rectangular surfaces E and F is shared with an upper base of the trapezoidal surface D. 前記三角形面ＧおよびＨが、３ＧＨｚにおける複素比誘電率の実部εｒ’が７以上１８以下であり、虚部εｒ”が４以上１５以下である電波吸収体用シート材から構成された、請求項４の電波吸収体。   The triangular surfaces G and H are made of a sheet material for a radio wave absorber in which a real part εr ′ of a complex relative dielectric constant at 3 GHz is 7 or more and 18 or less, and an imaginary part εr ″ is 4 or more and 15 or less. Item 4. An electromagnetic wave absorber according to item 4.

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