JP2001320188A - Shielding material from electromagnetic wave - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shielding material which can shield the interface between two members requiring to be shielded from electromagnetic waves without using such a special mechanism as a clamping mechanism. SOLUTION: The shielding material from electromagnetic waves has a base material 1 disposed on the surface of a member having a conductivity, a conductive projection 2 formed out of conductive fibers 5 stood on the surface of the base material (3, 4), and a connective member 4 for connecting electrically the conductive projection 2 with the member having a conductivity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electromagnetic wave shielding material for shielding electromagnetic waves.

[0002]

2. Description of the Related Art For example, a shield door provided at a doorway of a shield room for blocking electromagnetic waves and the like is provided with a structure for blocking electromagnetic waves leaking through a gap between the door and a door frame.
The structure shown in FIG. 5 is known as such a structure. In the structure shown in FIG. 5, a metal shield piece 22 is attached to the door 20, and a conductive shield cushion material 32 is provided on the door frame 30. When the door 20 is closed, the shield piece 22 provided on the door 20 is closed.
Are pressed by the shield cushion material 32 provided on the door frame 30, and the both are brought into close contact with each other. Thereby, both are electrically connected, and the electromagnetic wave leaking through the gap between the door 20 and the door frame 30 is blocked.

[0003]

However, in the above-mentioned conventional structure, it is necessary to press the shield piece 22 against the shield cushion material 32 to such an extent that the shield cushion material 32 is deformed, so that the door 20 is pressed against the door frame 30. There is a problem that a tightening mechanism is required. As described above, in the conventional structure, a special mechanism (a tightening mechanism) is used to maintain the electrical connection between the shield members (the shield piece 22 and the shield cushion material 32) disposed on the two members (the door 20 and the door frame 30). ) Was required.

Therefore, the present invention has been made based on the above-mentioned circumstances, and an object of the present invention is to use an electromagnetic wave leaking between two members requiring a shield without using a special mechanism such as a tightening mechanism. Provided is an electromagnetic wave shielding material capable of shielding the electromagnetic wave.

[0005]

Means and Effects for Solving the Problems (1) The electromagnetic wave shielding material according to claim 1, which has been made to solve the above problems, comprises: a base material provided on the surface of a conductive member; A conductive member formed by conductive fibers erected on the surface of the base member; and a connecting member for electrically connecting the conductive member to the conductive member. In the above-mentioned electromagnetic wave shielding material, since the conductive projection provided on the surface of the base material is formed of conductive fibers, the conductive projection easily deforms according to the shape of the contacting member. Therefore, electrical connection can be easily obtained without using a special mechanism such as a fastening mechanism. Further, the electromagnetic wave absorbed without being reflected by the conductive protrusion flows to a conductive member via the connecting member and is discharged. For this reason,
Electromagnetic waves absorbed by the conductive projections do not leak.

(2) It is preferable that the conductive projection is formed so that the tip is widened as the distance from the surface of the base material increases. According to such a structure, the density of the conductive fiber decreases as the distance from the base material surface increases, and the impedance of the conductive protrusion gradually increases as the distance from the base material surface increases.
Therefore, the radio wave absorption of the conductive protrusion can be increased.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electromagnetic shielding material according to an embodiment of the present invention will be described with reference to FIGS. 1 is an overall perspective view of the electromagnetic wave shielding material according to the present embodiment, FIG. 2 is a side view of the electromagnetic wave shielding material shown in FIG. 1, and FIGS. 3 and 4 are electromagnetic wave shielding materials according to the present embodiment. It is a figure explaining an application example which shields a gap between a door and a door frame using a material. As shown in FIGS. 1 and 2, an electromagnetic wave shielding material 10 according to the present embodiment includes a base tape 1 (corresponding to a base material described in the claims) and a conductive radio wave protruding from the surface of the base tape 1. It is composed of an absorber 2 (corresponding to a conductive projection in the claims).

As shown in FIG. 2, the base tape 1 includes a sheet material 3 and an adhesive layer 4 provided on the back surface of the sheet material 3. Since the conductive fibers 5 described later penetrate the sheet material 3 and are connected to the adhesive layer 4 having conductivity, the sheet material 3 does not need to have conductivity. The sheet material 3 is formed of a synthetic fiber woven fabric (for example, polyester, acrylic, glass fiber, or the like) or a soft synthetic resin (for example, vinyl chloride, silicone rubber, chloroprene rubber, or the like). The adhesive layer 4 is formed by attaching a commercially available conductive double-sided tape (for example, 791, 792 of Teraoka Seisakusho) to the back surface of the sheet material 3.

The radio wave absorber 2 protruding from the above-described base tape 1 is composed of a large number of conductive fibers 5 as shown in FIG. Each conductive fiber 5 is fixed to the base tape 1 such that its fixed end is in the adhesive layer 4 and its tip protrudes from the surface of the sheet material 3 in a predetermined direction. Further, as is apparent from FIG. 2, since the conductive fibers 5 protrude in a predetermined direction, the radio wave absorber 2 spreads laterally as the distance from the surface of the sheet material 3 increases. For this reason,
The density of the conductive fibers 5 (the number per unit area) decreases as the distance from the surface of the sheet material 3 increases. The above-mentioned conductive fiber 5 may be a synthetic fiber (for example, polyamide, acrylic, aramid, polyethylene terephthalate, polyurethane, polypropylene, or the like) having a surface plated with silver, nickel, copper, or the like. It is possible to use a synthetic fiber obtained by mixing a conductive material such as carbon fiber into the synthetic fiber.

FIGS. 3 and 4 show a case in which a gap between a door (made of steel) and a door frame (made of steel) of a shield door provided in a shield room is shielded by using the electromagnetic wave shielding material 10 configured as described above. This will be described with reference to FIG. 3 and 4
As shown in FIG. 2, in order to shield electromagnetic waves leaking from a gap between the door frame 6 and the door 7, for example, an electromagnetic wave shielding material 10 is attached to the door frame 6, and the door frame 6 and the door 7 are Make an electrical connection. Specifically, the electromagnetic wave shielding material 10 is attached to the door frame 6 from the adhesive layer 4 side,
The radio wave absorber 2 made of the conductive fiber 5 is brought into contact with the door 7. At this time, the radio wave absorber 2 is formed of the conductive fiber 5 and therefore has flexibility and easily deforms when it comes into contact with the door 7 to maintain its posture. Here, since the adhesive layer 4 is provided with conductivity by mixing a conductive material, the conductive fibers 5 are electrically connected to the door frame 6 (made of steel) via the adhesive layer 4, In addition, the tip of the conductive fiber 5 is a door 7.
The door 7 and the door frame 6 are electrically connected via the electromagnetic wave shielding member 10 by contact with the door 7. Therefore, the electromagnetic wave leaking into the gap between the door 7 and the door frame 6 is reflected or absorbed by the electromagnetic wave shielding material 10. Then, the electromagnetic waves absorbed by the electromagnetic wave shielding material 10 are discharged to a shield layer (earth wire) provided on the door 7 or the door frame 7.

As is apparent from the above description, the electromagnetic wave shielding material according to the present embodiment is a base tape 1
Since the electromagnetic wave absorber 2 protruding from is made of the conductive fiber 5 and is flexible, when it comes into contact with the door 7, it is easily deformed and its posture is maintained. Therefore, the conventionally required door 7
No need for a tightening mechanism for pressing the door against the door frame 6.

In the examples of FIGS. 3 and 4 described above, the radio wave absorber 2 of the electromagnetic shielding material 10 is brought into contact with the door 7 (a member on which the electromagnetic shielding material 10 is not provided). According to the electromagnetic wave shielding material 10 described above, even when the radio wave absorber 2 is not in contact with the door 7, a sufficient shielding effect can be achieved by the electromagnetic wave absorbing effect. That is, as described above, the radio wave absorber 2 of the electromagnetic wave shielding material 10 according to the present embodiment spreads laterally as the distance from the surface of the sheet material 3 increases (see FIG. 2). Therefore, the density of the conductive fibers 5 (the number per unit area)
Decreases as the distance from the surface of the sheet material 3 increases, and the impedance increases as the distance from the surface of the sheet material 3 increases. Therefore, the radio wave absorber 2 is configured so that the impedance gradually decreases from the tip side, and exhibits a good radio wave absorption ability. Therefore, according to the electromagnetic wave shielding material 10 according to the present embodiment, the radio wave absorber 2
Can be provided with a sufficient shielding effect even when the door is not in contact with the door 7. Further, in the above-described examples of FIGS. 3 and 4, the electromagnetic wave shielding material is attached to the door frame 6, but it goes without saying that the electromagnetic wave shielding material may be attached to the door 7 side. There is no. In addition, the conductive fibers 5 constituting the electromagnetic wave absorber 2 of the electromagnetic wave shielding material 10 are:
In addition to the state shown in FIG. 2, for example, a loop shape, a cilia shape,
It can be configured in the shape of a seal. Furthermore, by providing a release paper on the adhesive layer 4 side, an electromagnetic wave shielding effect can be easily imparted by peeling the release paper on a steel door (or door frame) and attaching it from the adhesive layer 4 side. . The examples shown in FIGS. 3 and 4 described above are examples in which the gap between the door and the door frame is shielded. However, the electromagnetic wave shielding material according to the present embodiment has various types of shielding electromagnetic waves leaking between the two members. (For example, a case for storing an electronic device that requires an electromagnetic wave shield).

Although the embodiment of the electromagnetic wave shielding material according to the present invention has been described in detail above, this is merely an example, and the present invention is implemented in various modified and improved forms based on the knowledge of those skilled in the art. can do.

[Brief description of the drawings]

FIG. 1 is a perspective view of an electromagnetic wave shielding material according to an embodiment of the present invention.

FIG. 2 is a side view of the electromagnetic wave shielding material shown in FIG. 1;

FIG. 3 is a view for explaining an example in which the electromagnetic wave shielding material shown in FIG. 1 is used to shield a gap between a door and a door frame.

FIG. 4 is a view for explaining another example in which the electromagnetic wave shielding material shown in FIG. 1 is used to shield a gap between a door and a door frame.

FIG. 5 is a diagram showing a conventional structure for shielding a gap between a door and a door frame.

[Explanation of symbols]

 1: base tape 2: radio wave absorber 3: sheet material 4: adhesive layer 5: conductive fiber 6: door frame 7: door

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5E321 AA14 AA42 AA45 BB41 BB44 CC16 GG01 GG05 GG11

Claims (2)

[Claims] 1. A base member provided on a surface of a member having conductivity, a conductive protrusion formed by conductive fibers erected on the surface of the base material, and a conductive protrusion An electromagnetic wave shielding material comprising a connection member for electrically connecting the conductive member. 2. The electromagnetic wave shielding material according to claim 1, wherein the conductive projection is formed so that a tip thereof is widened as the distance from the surface of the base material increases.