WO1994009609A1

WO1994009609A1 - Sheet material for shielding electromagnetic waves and method of constructing electromagnetic wave shielding

Info

Publication number: WO1994009609A1
Application number: PCT/JP1993/001452
Authority: WO
Inventors: Yasumasa Ouchi; Shoji Dohi; Masanori Matsuyama; Tatsuja Ito; Toshikazu Takeda; Katsuo Yoshida; Fumihiro Zama; Kazutoshi Tsutsumi; Toru Okui; Yukio Ishiketa; Yoshinobu Iyama; Haruka Ogawa
Original assignee: Osaka Gas Co., Ltd.; Obayashi Corporation
Priority date: 1992-10-08
Filing date: 1993-10-08
Publication date: 1994-04-28
Also published as: JPH06120691A

Abstract

A sheet material for shielding electromagnetic waves, characterized in that it consists of a soft, elastic, coarse, porous mat-like material formed by intertwining a plurality of conductive fibers (4) into a cotton-like material; and a method of constructing an electromagnetic wave shielding, comprising the steps of intertwining a plurality of conductive fibers (4) into a soft, elastic, coarse, porous mat-like electromagnetic wave shielding sheet material (2), and forming electromagnetic wave shielding by putting the sheet material (2) on the outer surface of a member, which defines a chamber in which electromagnetic wave shielding is to be formed, in such a manner that the above-mentioned outer surface as a whole is covered therewith to enclose the chamber as a whole. When this sheet material (2) is put on walls, floors, ceilings, and surfaces defining narrow space and clearances, a reliable electromagnetic wave shielding can be formed.

Description

Description Sheet material for electromagnetic wave shielding and method of applying electromagnetic wave shielding Technical field

The present invention relates to a sheet material for electromagnetic wave shielding and an electromagnetic wave shielding construction method, in which a large number of conductive fibers are entangled in a cotton-like shape to form a mat, and are used for walls, floors, ceilings, narrow places, gaps, and the like. TECHNICAL FIELD The present invention relates to an electromagnetic wave shielding sheet material provided in a vehicle, and an electromagnetic wave shielding construction method carried out using the sheet material. Background technology

Generally, in a broadcasting facility such as a TV station, since electromagnetic wave generating devices such as a wireless microphone are used, radio waves may be interfering between adjacent studios. In such a specific building, it is desirable to form an electromagnetic wave shield so that electromagnetic waves do not enter the room or leak from the room. This electromagnetic wave shield is formed by soldering, welding, or joining a plurality of plate-shaped shield members made of a conductive material such as a metal plate or a metal foil together with a copper tape. It is common to cover the entire interior. In particular, when using metal foil, the metal foil is easily damaged and requires careful handling, which takes time to install. Further, the metal foil is easily oxidized, and oxidation progresses remarkably at the peripheral portion of the metal foil, and the conductivity is impaired from this portion, and the electromagnetic shielding performance is reduced. Other electromagnetic wave shields

As disclosed in publications such as Japanese Patent Publication No. 2-879, there is also a method of disposing a resistive film and a radio wave absorbing material inside a double wall so as to face each other. In the latter technique, the standing wave generated inside the wall is absorbed by the resistive film and the radio wave absorbing material.

However, no matter which of the above methods is adopted, the following points are of concern. In electromagnetic wave shielding construction, sufficient consideration must be given to the joint of the plate-shaped shield members. In other words, although a sufficient electromagnetic wave shielding effect can be obtained at the sheet surface portion of the shield member, an adjacent shield portion is provided at the periphery of the shield member. There are likely to be places where structural continuity cannot be ensured accurately, such as gaps between the materials. If a gap is formed at the joint of the shield members, electromagnetic waves may enter or leak through the gap. As a result, a sufficient electromagnetic shielding effect cannot be obtained. Therefore, in the conventional electromagnetic wave shield construction, when joining the shield members, it is required to pay close attention to the work so that no gap is generated, and the mounting work is extremely complicated.

In order to avoid such a complicated operation, for example, a conductive sealing material is applied to a joint portion of the shield member. However, the number of processes for separately applying a sealing material increased, and it was not always possible to improve workability. It is also considered to be spliced with copper tape :; however, there were drawbacks such as the tape peeling off due to aging.

In addition, doors are provided in the rooms of the building, and through holes are formed in the walls and the like to introduce air conditioning equipment such as air conditioning ducts and electrical equipment into the rooms. For door equipment, door frames and doors made of metal materials will be used. In addition, a conductive mesh is provided in the through-hole portion in order to maintain the through-passage formed thereby and to minimize the invasion and leakage of electromagnetic waves from this through-passage. ing. By the way, the penetration hole ゃ Although it is impossible to prevent intrusion and leakage of electromagnetic waves from the opened door, there is a gap between the door and the door frame, or a gap that is inevitable due to the necessity of installation work, such as the above air conditioning duct. It is desired to form a reliable electromagnetic wave shield in the gap between the mounting part and the wall in the same manner as described above. Conventionally, as shown in Fig. 1, a metal “sealing” that is joined to the wall 50 or the air-conditioning duct 52 by means of bolting or welding as shown in Fig. 1 54 to cover this or apply a conductive sealing material. However, this work needs to be performed in a separate process in advance before the work of arranging the shielding material. Accordingly, the number of man-hours has increased, and the electromagnetic shielding work has been complicated. It is not a problem to work the sealing material downward, but if it is done upward, the sealing material will sag. Therefore, it is not a construction technology that can be applied to any location. On the other hand, these seams 54 and sealing materials are deteriorated by vibration load and heat load, and cannot maintain the hermeticity. Can be considered. Further, for door equipment, it is known to attach a conductive rubber packing between the door and the door frame. However, since this packing is mainly composed of rubber, it has poor conductivity, and a required electromagnetic wave shielding is required. Power that could not achieve the best performance.

On the other hand, it is needless to say that even in a room where such an electromagnetic wave shield is formed, heat insulation performance and sound absorption performance are required as in a general room. Among the materials used as heat insulation and sound absorbing materials, there is no known material that can expect an electromagnetic wave shielding effect. Therefore, in order to ensure the heat insulation performance and sound absorption performance, as in the case of the electromagnetic wave shield construction, multiple pieces of glass wool etc. that exhibit the heat insulation effect and sound absorption effect are joined together. Cover. Therefore, in order to form the electromagnetic wave shield room, the shield member and the glass wool had to be disposed twice by the same operation, and the workability was extremely good. Disclosure of the invention

An object of the present invention is to provide a novel sheet material for electromagnetic wave shielding having good workability and handleability, and an electromagnetic wave shield construction method using the same.

In particular, it is an object of the present invention to provide a new sheet material for electromagnetic wave shielding that can easily and accurately perform joining work between adjacent sheet materials in a small number of steps without using a conductive sealing material or the like. An object of the present invention is to provide a sheet material for an electromagnetic wave shield and a method for constructing an electromagnetic wave shield capable of obtaining a reliable electromagnetic wave shield effect without deterioration over time.

Further, an object of the present invention is to provide an electromagnetic wave shield capable of performing a reliable electromagnetic wave shield construction by a simple operation of simply filling the above-mentioned sheet material for electromagnetic wave shield into a narrow portion or a gap portion of a room. An object of the present invention is to provide a shielding sheet material and an electromagnetic wave shielding construction method.

Furthermore, an object of the present invention is to provide a new sheet material for electromagnetic wave shielding, which can simultaneously perform heat insulation and sound absorbing work, and can easily and inexpensively perform work required for a room. Sheet material and electromagnetic wave shielding construction method To provide.

The sheet material for electromagnetic wave shielding of the present invention is characterized in that a large number of conductive fibers are entangled in a cotton-like shape to form a coarse, porous, flexible and elastic mat. Preferably, both sides or one side of the sheet material are impregnated with a synthetic resin or coated with a synthetic resin.

It is preferable that the diameter of the conductive fiber is several meters to several hundred hundreds // m.

The conductive fiber is preferably a carbon fiber, a metal fiber made of steel, or a metal fiber made of stainless steel.

The sheet material is disposed on the indoor surface and used as a heat insulating material and a sound absorbing material. In some cases, the sheet material may be used as a carpet base.

As a preferred example, the sheet material for electromagnetic wave shielding is formed by entanglement of a large number of conductive fibers, which are carbon fibers, into a cotton-like shape, and is formed into a coarse porous, flexible, resilient mat shape. It is disposed on the surface of the member that defines the chamber in which the electromagnetic wave shield is to be formed, so that it can also function as a sound absorbing material and a heat insulating material.

Further, as another preferred example, the electromagnetic wave shielding sheet material is formed in a coarse porous soft elastic resilient mat shape by entanglement of a large number of conductive fibers which are carbon fibers. It is formed by impregnating or coating a synthetic resin on both sides or one side, and is disposed on the surface of the member that defines the chamber in which the electromagnetic wave shield is to be formed, and also functions as a sound absorbing material and a heat insulating material. .

On the other hand, the electromagnetic wave shielding construction method of the present invention includes a step of preliminarily forming a coarse porous soft and resilient mat-shaped electromagnetic wave shielding sheet material by entanglement of a large number of conductive fibers in a cotton-like manner. A step of forming an electromagnetic wave shield by arranging the sheet material so as to cover the entire surface of the member and cover the entire room, on a member surface defining and forming a chamber in which an electromagnetic wave shield is to be formed. Special.

The step of forming the sheet material for electromagnetic wave shielding includes a step of impregnating a synthetic resin on both surfaces or one surface of the sheet material to form a panel, or a method of forming both surfaces or one surface of the sheet material. It is preferable to include a step of coating a synthetic resin. After the step of disposing the sheet material to form the electromagnetic wave shield, a step of attaching a finishing material to the member so as to hide the sheet material between the member and the surface of the member. It may be implemented.

The step of disposing the sheet material and forming the electromagnetic wave shield may include a step of overlapping peripheral portions of adjacent sheet materials with each other.

It is preferable that the overlapping margin in the overlapping step is at least twice the thickness of the sheet material provided.

The step of arranging the sheet material to form an electromagnetic wave shield is also a heat insulation construction and a sound absorption construction.

In addition to the step of arranging the sheet material to form an electromagnetic wave shield, the step of filling the sheet material so as to close a narrow portion and a gap portion of the chamber is performed.

As the clearance, for example, there is a mounting clearance between a wall of the chamber and a duct installed in the chamber.

The narrow portion is a space between a door of the room and a door frame.

As a preferred example, the electromagnetic wave shielding method is a method of entanglement of several conductive fibers, which are carbon fibers, into a cotton-like shape, and forming a rough porous, flexible and resilient mat-shaped electromagnetic shielding sheet material. Forming the electromagnetic wave shield by forming the electromagnetic wave shield in advance, and disposing the above-mentioned sheet material on the surface of the member defining the chamber where the electromagnetic wave shield is to be formed, so as to cover the entire surface of the member and cover the entire room. And filling the sheet material so as to close the narrow part and the gap part of the chamber. The step of arranging the sheet material and forming the electromagnetic wave shield is In addition, the method includes a step of overlapping peripheral portions of adjacent sheet materials with each other, and the above-mentioned steps are heat insulation work and sound absorption work.

Another preferred example of the electromagnetic wave shielding method is a method in which several conductive fibers, which are carbon fibers, are entangled in a cotton-like shape, and a coarse, porous, flexible, resilient mat-shaped electromagnetic wave shielding sheet is used. A step of forming a material in advance, a step of impregnating synthetic resin on both sides or one side of the sheet material to form a panel, and a step of forming a chamber in which an electromagnetic wave shield is to be formed on the surface of the member. Disposing the paneled sheet material to form an electromagnetic wave shield so as to cover the entire room by covering the entirety of the room, and to cover the gap between the adjacent sheet materials. The string-shaped part which converged the carbon fiber And a process of filling the material, wherein the above process is also a heat insulating construction and a sound absorbing construction. Another preferred example of the electromagnetic wave shielding method is a method in which conductive fibers, which are carbon fibers, are entangled in a cotton-like shape to form a coarse, porous, flexible and resilient mat-shaped electromagnetic wave shielding system. A step of forming a sheet material in advance, a step of coating a synthetic resin on both sides or one side of the sheet material, and a step of covering the entire surface of the member that defines a chamber in which an electromagnetic wave shield is to be formed. Forming the electromagnetic wave shield by arranging the sheet material so as to cover the entire room, and forming the electromagnetic wave shield by arranging the sheet material. The method further comprises a step of overlapping the parts with each other, and the above-mentioned step is also a heat insulating work and a sound absorbing work. The sheet material can be arranged with good workability on the surface of the member that defines the room where the electromagnetic wave shield is to be formed, and of course, the conductive sealing material can be used for joining the sheet materials. It is possible to easily and accurately perform the joining work between adjacent sheet materials with a small number of steps without using a wire, and to obtain a reliable electromagnetic wave shielding effect without deterioration over time.

In addition, reliable electromagnetic wave shielding can be performed by simple work of simply filling the above-mentioned electromagnetic wave shielding sheet material into a narrow part or a gap part of a room.

In addition, heat insulation and sound absorption can be performed all at once, and the required construction for the room can be performed easily and inexpensively.

Furthermore, by impregnating or coating a synthetic resin on both sides or one side of the sheet material, the bonding force between the conductive fibers is increased, so that the sheet material is formed into a panel or a long roll sheet. This greatly simplifies the handling of the sheet material applied to the inner surface of the room, thereby greatly reducing the cutting work and significantly reducing the scattering of carbon fibers at the cutting location. Can be reduced. In addition, since the inner surface of the room, including the gaps, can be composed entirely of conductive fiber sheet material, it is not only extremely excellent in corrosion resistance, but also excellent in earthquake resistance, heat resistance, weather resistance and semi-permanently. Shielding performance can be maintained.

In addition, a sheet material made into a panel by impregnating the surface with synthetic resin is applied to the entire inner surface of the room. In addition to the arrangement, the gap between adjacent sheet materials is filled with a string-like member in which conductive fibers are converged, so that an electromagnetic wave shield can be formed without any gap over the entire room. In addition, the sheet material formed into a panel has a considerable strength because it is impregnated with synthetic resin, and can be used as a base material. In addition, since the bonding force between fibers is increased, handling such as transportation and laying is remarkable. It is simple and can greatly reduce the scattering of carbon fibers from the cut part.

In addition, the sheet material coated with synthetic resin on the surface is placed on the entire inside surface of the room, and the adjacent sheet materials are overlapped with each other, so that an electromagnetic wave shield can be formed on the entire surface of the room without gaps . In addition, since the sheet material is coated with a synthetic resin on the surface, the bonding force between the fibers is increased, so that the sheet material can be made longer, exhibit flexibility, and be handled in a roll sheet shape. As a result, it is possible to simplify the work such as transporting and pasting, and to greatly reduce the cutting work, as well as to greatly reduce the scattering of carbon fibers at the cutting location. BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 is a perspective view for explaining an example of electromagnetic wave shield installation for a conventional gap.

FIG. 2, _c 3 FIG is a perspective view showing an example of an electromagnetic wave shielding sheet one preparative material according to the present invention, is a graph illustrating the electromagnetic wave shielding performance.

Figure 4 is a _c Fig. 5 main part is a cross-sectional view of the ceiling portion showing a state in which is disposed the sheet material to the ceiling is a fragmentary sectional view of a wall portion showing a state in which is disposed the sheet material to the wall is there. Fig. 6 is a cross-sectional view of a main part of a double wall portion showing a state in which a sheet material is provided on a double wall. Fig. 7 is a cross-sectional view of a main portion of a floor portion showing a state in which a sheet material is provided on a floor. FIG. FIG. 8 is a perspective view showing a state where a sheet material is disposed in a gap between the wall and the air conditioning duct.

FIG. 9 is a cross-sectional view of a main part showing a state where sheet materials are provided in door equipment.

FIG. 10 is a graph showing the electromagnetic wave shielding performance when a sheet material is attached to door equipment. FIG. 11 is a perspective view showing another example of the sheet material for electromagnetic wave shielding according to the present invention.

FIG. 12 is a perspective view showing an example of a method of applying an electromagnetic wave shield using the sheet material shown in FIG. 11 and showing an attached state of a sheet material.

FIG. 13 is a perspective view showing a filling state of a string-like member into a gap portion of a sheet material in the construction method of FIG.

FIG. 14 is a graph comparing the electromagnetic wave shielding performance of a sheet material impregnated with synthetic resin and a sheet material not impregnated with synthetic resin.

FIG. 15 is a perspective view showing still another example of the sheet material for electromagnetic wave shielding according to the present invention.

FIG. 16 is a perspective view showing an example of an electromagnetic wave shielding construction method using the sheet material shown in FIG. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 2 is a perspective view showing one embodiment of the electromagnetic wave shielding sheet material 2 according to the present invention.

This sheet material 2 is formed of conductive fibers 4. Specifically, the sheet material 2 is formed by entanglement of a large number of ultrafine conductive fibers 4 having a diameter of several μπι to several 100 μπι in a cotton-like manner. The sheet material 2 to be formed is formed as a coarse, porous, flexible and elastic mat. The conductive fibers 4 are carbon fibers in the present embodiment, and the sheet material 2 is formed by entangled the carbon fibers in a curl shape. FIG. 3 is a graph showing the electromagnetic wave shielding performance when a sheet material 2 having a thickness of 6 to 7 mm is used as a sample. According to this sheet material 2, it is about 70 to 30 dB at 5 to 30 MHz corresponding to the HF band, and 40 to 100 dB at 100 to 100 MHz from the VHF band to the UHF band. : Attenuation of electromagnetic waves of about L 0 0 dB was obtained. The conductive fiber 4 may be any fiber having conductivity, and may be not only carbon fiber but also metal fiber such as stainless steel or steel.

Next, an example of a general electromagnetic wave shielding construction method using the sheet material 2 will be described. When shielding electromagnetic waves inside a building, etc., use sheet material 2 Cover the entire room. Specifically, the sheet material 2 is disposed on the back side of the finishing materials 12, 14, 16 attached to the surface of the structure that partitions the room, such as the wall 6, the floor 8, the ceiling 10, and the like. As shown in FIG. 4 to FIG. 7, the sheet material 2 is laid on the back side of the finishing material 16 of the ceiling 10 (FIG. 4), or on the back side of the finishing material 12 of the wall 6 (FIG. 5). (See Fig. 6) It is installed inside the double wall 18 that separates from other rooms (Fig. 6), or is set up on the back side of the finishing material 14 on the floor 8 (Fig. 7). Regarding the joining of the sheet materials 2, the peripheral edges of the sheet materials 2 are overlapped with each other. This overlapping margin may be about twice the thickness of the sheet material 2. The sheet material 2 can be joined without gaps only by the operation of simply overlapping the peripheral portions of the sheet material 2 with each other. Then, with such a simple operation, the entire room can be completely covered with the sheet material 2, and an electromagnetic wave shielding room can be obtained. That is, when the sheet material 2 of the present invention is used, there is no need to apply an electromagnetic wave shield using a conventional method such as a conductive sealing material. In particular, since the sheet material 2 is a molded material made of the conductive fiber 4, the electromagnetic wave shielding effect is essentially high. In addition to this, since the sheet material 2 is formed into a soft mat, the sheet material 2 is excellent in handleability, and such good handleability can save labor in construction.

Further, as described above, the sheet material 2 is formed into a coarse porous shape by entanglement of a large number of microfibers 4 in a cotton-like manner, and has essentially many voids, so that it has both excellent heat insulating performance and sound absorbing performance. I do. Therefore, the sheet material 2 according to the present invention can be used as a heat insulating material or a sound absorbing material, and a good heat insulating performance and a good sound absorbing performance can be obtained together with an electromagnetic wave shielding effect, thereby saving labor in the construction of the electromagnetic wave shielding room. And economic efficiency. That is, when the electromagnetic wave shielding room is constructed, if the sheet material 2 according to the present invention is used, it is not necessary to prepare another material for heat insulation and sound absorption. As a result, the material cost can be reduced, and the work for attaching the different material can be eliminated. Further, since the sheet material 2 is flexible and elastic, it does not cause damage such as cracks against vibration and thermal deformation, and can maintain the electromagnetic wave shielding performance almost permanently. The sheet material 2 according to the present invention is used in various ways, such as using it as a base for a carpet.

Next, an embodiment of a special electromagnetic wave shielding construction method using the sheet material 2 according to the present invention will be described. The sheet material 2 of this embodiment exhibits the performance described above. Is, of course. FIG. 8 shows a part of the wall surface 6 of the electromagnetic wave shielding room. The above-mentioned sheet material 2 is disposed on the wall 6 of the electromagnetic wave shielding room, and the electromagnetic wave shielding is performed. Electromagnetic shielding is also applied to the inside of the air-conditioning duct 20 that is provided through the wall 6 by a general method.

By the way, considering the case where the air conditioning duct 20 is attached to the through hole formed in the wall 6, as described in the related art, there is a gap between the duct 20 and the wall 6, and the gap exists. Therefore, electromagnetic wave shield construction is complicated. This embodiment is an example of construction in which the gap is filled with the sheet material 2 of the present invention. Since the sheet material 2 according to the present invention is porous and flexible and easily deformed, it can be filled in gaps or the like and filled with various shapes and dimensions simply by pasting. This makes it possible to easily apply electromagnetic wave shielding to narrow places and gaps ₍ Fig. 9 shows an example of applying electromagnetic wave shielding to the opening and closing portions of doors 22 and the like. in _c the embodiment cram sheet one preparative material 2 in the gap between the door 2 2 and the door frame 2 4, the door frame 2. 4, part 2 6 door 2 2 abuts the sheet material 2 is Zhang Since the sheet material 2 of the present invention is a flexible cotton-like material and has elasticity, it is extremely preferable to use the sheet material 2 for electromagnetic wave shielding in a gap portion that may move in this manner. The figure shows the case where sheet material 2 is attached to door frame 24 and Fig. 4 is a graph showing the electromagnetic wave shielding performance of the electromagnetic wave shielding room for comparison with the case where the sheet material 2 is not adhered to the door frame 24 than the case where the sheet material 2 is not attached. It is large and has a high shielding effect. In particular, an attenuation of about 40 to 60 dB can be obtained at 30 MHz to 100 MHz.

By the way, in the electromagnetic wave shielding sheet material 2 described above, since the conductive fibers 4 such as carbon fibers are simply entangled and formed in a mat shape, the tensile strength of the mat is relatively weak, and the roll sheet is formed. It can be considered that it may be difficult to handle due to breakage of its own weight when it is formed to be 3 m or longer as in . Further, when the sheet material 2 is cut at the site, there is a possibility that the fiber 4 scatters about 5 to 10 g Zm ² and the working environment is deteriorated.

Hereinafter, another example of the present invention which is improved in consideration of the above circumstances will be described. Fig. 11 to Fig. 14 show the sheet 28 for electromagnetic wave shielding of the other embodiment and the method of applying the electromagnetic wave shielding by using the same, and Fig. 11 shows the mat shown in Fig. 2 above. A perspective view showing the sheet material 28 impregnated with the synthetic resin 34, FIG. 12 and FIG. 13 are explanatory diagrams sequentially showing the process of applying the sheet material 28, and FIG. 14 shows the electromagnetic wave shielding performance. FIG.

That is, the sheet material 28 for electromagnetic wave shielding of the present embodiment is formed by curling a single material of the carbon fiber 4 described with reference to FIG. Both surfaces or one surface of a mat 32 of 0 g / m ² are impregnated with a synthetic resin 34 as shown in FIG. By impregnating the surface of the mat 32 with the synthetic resin 34 in this manner, the entire sheet material 28 is cured to have a panel shape. Since the sheet material 28 of this embodiment is based on the mat shown in FIG. 2, it is a matter of course that the same performance can be obtained.

The paneled sheet material 28 is cut into a predetermined rectangular shape, and as shown in FIG. 12, a base material panel is formed inside a light iron base material 36 which forms a framework of a room to be shielded one after another. To cover walls, floors and ceilings. At this time, a gap is provided between each of the adjacent sheet members 28 and the joining portion, and as shown in FIG. 13, a string-like member 38 in which conductive fibers such as carbon fibers are converged in these gaps. Pack without gaps. As the cord-like member 38, a felt-like cord made of a conductive fiber, which is cut in advance by size so that it can be inserted into the gap, and formed into a cord-like shape having elasticity is used.

Therefore, by covering the entire inner surface of the room with the paneled sheet material 28 and filling the string-shaped member 38 between the joints, it is possible to completely shield the room, thereby preventing leakage and penetration of electromagnetic waves. Can be shut off. Fig. 14 is a graph showing the electromagnetic wave shielding performance of 100 to 100 MHZ in the UHF band as an example, compared with sheet material 2 not impregnated with synthetic resin. It was confirmed that almost the same electromagnetic wave shielding performance can be obtained in the case of the above.

FIGS. 15 and 16 show still another example. In the electromagnetic shielding sheet 40 of this example, the synthetic resin 42 is coated on both surfaces or one surface of the mat 32. To form a sheet. Therefore, the sheet material 40 for electromagnetic wave shielding of this embodiment is formed in a sheet shape and has flexibility, and the sheet material 40 is bonded to the wall, floor and ceiling of the room. That is, as shown in FIG. 16, the sheet material 40 is attached with a base board 44 inside a light iron base material 36 and sequentially attached inside the base board 44. At this time, the adjacent ones of the sheet materials 40 are overlapped with each other (overlap width of about 10 Omm) to prevent the generation of a gap.

Therefore, in this embodiment, the same electromagnetic wave attenuation characteristics as those of the above embodiment can be obtained by bonding the sheet-shaped sheet material 40 to the inner surface of the room without any gap. Since the sheet materials 40 can be superimposed on each other and stuck together without any gaps by making the sheet shape, the construction can be greatly simplified. Incidentally, even in the case of such a sheet-like sheet material 40, when a gap is provided between the joining portions of the pieces to be joined, and the sheets are sequentially bonded, the bonding is performed in the same manner as in the above embodiment. It can be constructed by filling the joint gap with a string-like member.

By the way, in each of the above-described embodiments, the sheet material 28, 40 is formed by impregnating or coating the synthetic resin 34, 42 with the mat 32 in which the conductive fiber 4 is entangled. Since the bonding force of each fiber 4 is increased, the scattering of the fiber 4 when cut can be reduced to 1 g Zm ² or less, and especially when the sheet 4 is formed into a sheet shape, the sheet material 40 Can be formed as a long object of 10 m or more. In addition, since the entire inner surface of the room is made of sheet material 28 and 40, there is no problem of corrosion resistance in the gaps, and it is semi-permanently maintained with excellent earthquake resistance, heat resistance, and weather resistance. can do.

• Comparative Example 1

When using the carbon fiber sheet material shown in Fig. ^{2 with} a thickness of 7 mm and a basis weight of 300 g Zm ² by the conventional construction method, carbon fibers of 9 g Zm ² are scattered during cutting and pasting work. However, the sheet materials shown in FIGS. 11 and 15 could reduce the scattering.

Comparative Example 2

The sheet material shown in Fig. 2 was formed as a 3.5 m long object, and the construction was attempted.However, the sheet material was broken by its own weight and construction was impossible. Shi The coating material has made it possible to form long objects.

'' Industrial applicability

As described above, the sheet material for electromagnetic wave shielding of the present invention can be used not only as an original electromagnetic wave shielding function but also as a heat insulating material, a sound absorbing material, and also as a carpet base, etc. In this way, insulation and sound absorption can be performed simultaneously.

Claims

The scope of the claims

1. A sheet material for electromagnetic wave shielding, characterized in that a large number of conductive fibers are entangled in a cotton-like shape to form a coarse porous, flexible and elastic mat.

2. A sheet material for electromagnetic wave shielding, characterized in that synthetic resin is impregnated on both sides or one side of the sheet material for electromagnetic wave shield according to claim 1.

3. A sheet material for electromagnetic wave shielding, characterized in that a synthetic resin is coated on both sides or one side of the sheet material for electromagnetic wave shield according to claim 1.

4. The sheet material for an electromagnetic wave shield according to claim 1, wherein the diameter of the conductive fiber is a number to a number 100 / m.

5. The sheet material for electromagnetic wave shielding according to claim 1, wherein the conductive fiber is a carbon fiber.

6. The sheet material for electromagnetic wave shielding according to claim 1, wherein the conductive fiber is a steel metal fiber.

7. The sheet material for electromagnetic wave shielding according to claim 1, wherein the conductive fiber is a metal fiber made of stainless steel.

8. A sheet material for electromagnetic wave shielding, wherein the sheet material according to claim 1 is disposed on an indoor surface and used as a heat insulating material.

9. A sheet material for electromagnetic wave shielding, wherein the sheet material according to claim 1 is disposed on an indoor surface and used as a sound absorbing material.

10. A sheet material for electromagnetic wave shielding, wherein the sheet material according to claim 1 is used as a carpet base.

1 1. A large number of conductive fibers, which are carbon fibers, are entangled in a cotton-like shape, and are formed into a coarse, porous, flexible and elastic mat, and sound is absorbed on the surface of a member that defines a chamber in which an electromagnetic wave shield is to be formed. A sheet material for electromagnetic shielding, which is also provided as a material and a heat insulating material.

1 2. A large number of conductive fibers, which are carbon fibers, are entangled in a cotton-like shape to form a coarse, porous, flexible and elastic mat, and both or one surface thereof is impregnated or coated with a synthetic resin. Should be formed to form an electromagnetic wave shield A sheet material for electromagnetic wave shielding, which is also provided as a sound absorbing material and a heat insulating material on the surface of a member that partitions a room.

1 3. In the electromagnetic wave shield construction method,

A step of pre-forming a coarse porous, flexible and resilient mat-shaped electromagnetic wave shielding sheet material by entanglement of a large number of conductive fibers in a cotton-like manner;

A step of forming an electromagnetic wave shield by arranging the sheet material on a surface of a member defining a chamber in which an electromagnetic wave shield is to be formed and covering the entire surface of the member to cover the entire room;

A method for constructing an electromagnetic wave shield, comprising:

14. The method according to claim 13, wherein the step of forming the electromagnetic wave shielding sheet material includes a step of impregnating both sides or one side of the sheet material with a synthetic resin to form a panel. Electromagnetic wave shield construction method.

15. The electromagnetic wave shielding construction method according to claim 13, wherein the step of forming the electromagnetic wave shielding sheet material includes a step of coating a synthetic resin on both surfaces or one surface of the sheet material.

1 6. After the step of arranging the sheet material to form an electromagnetic wave shield, a step of attaching a finishing material to the member to conceal the sheet material from the surface of the member. The electromagnetic wave shielding construction method according to claim 13, which is characterized in that:

17. The electromagnetic wave shielding construction method according to claim 13, wherein the step of arranging the sheet material to form an electromagnetic wave shield includes a step of overlapping peripheral portions of adjacent sheet materials with each other. .

18. The method according to claim 17, wherein an overlap margin in the superimposing step is at least twice a thickness of the sheet material to be arranged.

19. The electromagnetic wave shielding method according to claim 13, wherein the step of arranging the sheet material to form an electromagnetic wave shield is also a heat insulating operation.

20. The method according to claim 13, wherein the step of arranging the sheet material to form an electromagnetic wave shield is also a sound absorbing operation.

21. A step of arranging the sheet material to form an electromagnetic wave shield, and filling the sheet material so as to cover a narrow portion and a gap portion of the chamber. 14. The method according to claim 13, wherein the step is performed.

22. The electromagnetic wave shielding construction method according to claim 21, wherein the gap portion is a gap between a wall of the chamber and a duct provided in the chamber.

23. The method according to claim 21, wherein the narrow portion is a space between a door of the room and a door frame.

2 4. In the electromagnetic wave shield construction method,

A process in which several conductive fibers, which are carbon fibers, are entangled in a cotton-like shape to preliminarily form a coarse, porous and flexible mat-like electromagnetic shielding sheet material; and A step of forming the electromagnetic wave shield by arranging the sheet material on the surface of the member forming the chamber to cover the entire surface of the member and covering the entire room;

A step of filling the sheet material so as to close a narrow portion and a gap portion of the chamber,

Consisting of

The step of arranging the sheet material to form an electromagnetic wave shield includes a step of overlapping peripheral portions of adjacent sheet materials with each other,

Furthermore, the electromagnetic wave shielding construction method characterized in that the above-mentioned steps are insulation construction and sound absorption construction.

2 5. In the electromagnetic wave shield construction method,

A step of preliminarily forming a coarse porous soft and resilient mat-shaped sheet for electromagnetic wave shielding by entanglement of several conductive fibers which are carbon fibers in a cotton-like manner; A step of impregnating the synthetic resin on both sides or one side of the panel to form a panel,

A step of arranging the above-mentioned paneled sheet material so as to cover the entire surface of the member and to cover the entire room on the surface of the member that defines the room in which the electromagnetic wave shield is to be formed; and forming an electromagnetic wave shield. ,

Filling a string-like member having carbon fibers converged so as to close a gap between adjacent sheet materials;

Consisting of An electromagnetic shielding method, wherein the above-mentioned process is also a heat insulating work and a sound absorbing work.

2 6. In the electromagnetic wave shield construction method,

A step of preliminarily forming a coarse porous soft and resilient mat-shaped electromagnetic wave shielding sheet material by entanglement of several conductive fibers which are carbon fibers in a cotton-like manner;

Coating a synthetic resin on both sides or one side of the sheet material;

Consisting of

Further, an electromagnetic wave shielding construction method characterized in that the above-mentioned steps are insulation construction and sound absorption construction.