JP5247315B2 - Translucent electromagnetic shielding plate - Google Patents

Description

The present invention relates to a translucent electromagnetic wave shielding plate, and more particularly to a translucent electromagnetic wave shielding plate in which a conductive fiber mesh is sandwiched between a pair of transparent plates.

In a building such as an intelligent building, there is a demand for the entire or part of the building to be an electromagnetic shielding space for the purpose of passively or actively shielding electronic devices such as computers. Recently, the use of strong magnetic devices such as MRI (Magnetic Resonance Imaging) apparatus is increasing in medical facilities and the like, and there is an increasing demand for an MRI examination room or the like as an electromagnetic shielding space. The electromagnetic shielding space basically has a structure that covers all the walls, floors, ceilings, etc. around the space using a conductive electromagnetic shielding plate. When providing windows, etc., a transparent electromagnetic shielding plate (hereinafter referred to as translucent property) It may be necessary to use a shield plate). As such a translucent shield plate, as shown in FIG. 5A, a transparent adhesive layer (for example, ethylene acetate) is interposed between a pair of transparent plates (for example, made of glass or transparent resin) 32 and 33. A shield plate is used in which a conductive mesh (for example, a metal fiber mesh or the like) 34 is sandwiched between vinyl resin (EVA-based adhesive layers) 35 and 36 (see Patent Documents 1 to 3).

The translucent shield plate 31 shown in FIG. 5A projects from the transparent plates 32 and 33 by projecting the tip (outer edge) of the conductive mesh 34 sandwiched between the transparent plates 32 and 33. The front end of each of the transparent plates 32, 33 is bent to the surface side of the transparent plate 32, 33, and the folded conductive mesh 34 is covered with a conductive coating material 37 (for example, conductive tape) straddling between the surfaces of both transparent plates 32. is there. Although the illustrated example shows only a cross-sectional view of one side, the other sides have the same structure. FIG. 5B shows a method of attaching the shield plate 31 of the illustrated example to the sash 20 such as a window frame in the electromagnetic wave shield space. The sash 20 in the illustrated example has a conductive coating 29 that is electrically connected to a surrounding wall or the like. For example, the pushing edge 21 of the sash 20 is removed and the shield plate 31 is placed on the setting block 22, and the mesh structure conductor (the conductive conductor 37 of the shield plate 31 and the conductive coating 29 of the sash 20 are placed between the conductive cover 37. For example, a mesh structure is formed by knitting a metal wire), and the shield plate 31 is electrically connected to surrounding walls and the like through the mesh structure conductor 26 and the sash 20. As described above, the shield plate 31 in the illustrated example is easy to attach to and remove from the sash 20, and has an advantage of facilitating the construction of the electromagnetic shielding space. In the figure, reference numeral 27 denotes a backup material for the sash 20, and reference numeral 28 denotes a sealing material.

In addition, in MRI examination rooms and the like, there is a demand to provide a relatively large window in the electromagnetic wave shielding space so that the subject can be assured and the subject can be observed from the outside. Patent Document 4 proposes a method of providing a translucent wall or a wide window as shown in FIG. 4 in an MRI examination room or the like using a translucent shield plate 31 as shown in FIG. In an MRI examination room or the like, a magnetic shield with a relatively low frequency is required together with a radio wave shield with a relatively high frequency. In the illustrated example, the translucent shield plates 31 are arranged in parallel to be doubled, and a plurality of magnetic plates 41 are arranged between the shield plates 31 so that the central axes in the length direction are arranged substantially in parallel at a predetermined interval on the same plane. A three-layer structure is formed by arranging a laminated body 40 (hereinafter also referred to as a magnetic shield enclosure). The magnetic shield housing 40 shown in the illustrated example has a sufficiently small cross-sectional area between the magnetic plates 41 with respect to the cross-sectional area and relative permeability of each magnetic plate 41 so that the magnetic flux in the magnetic plate 41 can be easily passed. By making the thickness (permeance of the magnetic plate) greater than the ease of passing the magnetic flux in the interval (permeance of the interval), a structure having both magnetic shielding performance and translucency can be obtained (Patent Document 5). reference). By arranging the translucent shield plate 31 and the magnetic shield housing 40 in parallel as in the illustrated example to form a triple structure, a wall or a wide window having both radio wave shielding, magnetic shielding, and translucency are provided. can do. Reference numeral 20 in the figure denotes a sash similar to that shown in FIG. 5B that allows the translucent shield plate 31 to conduct to the surrounding floor or ceiling, and reference numeral 39 designates a plurality of translucent shield plates 31 to conduct each other. The joining member connected in a row is shown.

Japanese Patent Laid-Open No. 09-1000014 JP 11-312893 A JP 2004-359517 A JP 2007-035767 A International Publication No. 2004/084603 JP 2003-025470 A Japanese Patent Laying-Open No. 2005-311189

For example, in an MRI examination room as shown in FIG. 4 and the like, the translucent shield plate 31 has a translucency for transmitting 50% or more visible light and a shielding performance for shielding an electromagnetic wave of 5 MHz to 1 GHz by 80 to 100 dB or more. May be required at the same time. In order to obtain the light-transmitting shield plate 31 having such a high light-transmitting property and shielding performance, it is effective to reduce the fiber diameter of the mesh 34 and increase the fiber density (weave density). However, the translucent shield plate 31 using the conductive mesh 34 made of metal fiber as shown in FIG. 5 has a problem that it is difficult to simultaneously improve translucency and shield performance.

That is, if the metal fiber has a fine wire diameter (for example, 50 μm or less), the fiber is likely to be twisted, and if the weaving density is high (for example, 100 fibers / 1 inch or more), the weaving property is deteriorated. This may cause a decrease in the translucency of the mesh 34. On the contrary, when a metal fiber having a certain strength with a thick wire diameter is used, light reflection is increased (dazzled) due to surface gloss, and the translucency is lowered. A technology for suppressing light reflection by providing a black oxide film on the surface of the metal fiber has also been developed. However, since the surface conductivity of the mesh 34 is lowered due to the insulating property of the black oxide film, it is conductive as shown in FIG. Before covering with the covering material 37, the operation | work etc. which thin or remove the black oxide film of the front-end | tip of the mesh 34 are needed (refer patent documents 1-3). Such an operation is very time consuming and it is difficult to stabilize the quality, which may cause a reduction in the shielding performance of the translucent shield plate 31.

On the other hand, by using a conductive mesh (hereinafter sometimes referred to as a conductive fiber mesh) provided with a metal coating on the surface of a mesh fabric in which synthetic fibers or natural fibers are woven at a required weaving density, a translucent shield is used. It can be expected that the electromagnetic wave shielding performance and translucency of the plate 31 are improved at the same time. For example, a black conductive fiber mesh having a fiber diameter of 20 to 50 μm and a weaving density of 50 to 300 / inch has been developed (see Patent Documents 6 and 7). It can be considered that the conductive mesh 34 made of 5 (A) metal fiber is used instead.

However, when an external force such as bending is applied to the conductive fiber mesh, the metal coating on the surface is easily peeled off, and there is a problem that the conductivity (conductivity with the outside) is likely to decrease due to the external force. For example, as shown in FIG. 5A, when the outer edge of the mesh protruding from the transparent plates 32 and 33 is folded and covered with a conductive coating material or the like, at least a part of the metal coating of the mesh is peeled off at the bent portion and becomes conductive. As a result, the translucent shield plate 31 may not be able to have the designed shielding performance. In order to manufacture the translucent shield plate 31 having a stable quality using the conductive fiber mesh, it is necessary to devise a technique for suppressing the external force applied to the mesh as small as possible to prevent the metal coating on the surface from peeling off.

Accordingly, an object of the present invention is to provide a translucent electromagnetic wave shielding plate having a stable quality using a conductive fiber mesh.

Referring to the embodiment of FIG. 1, the translucent electromagnetic wave shielding plate 1 of the present invention leaves strip-shaped non-overlapping portions S1 to S4 around the periphery of a similar large transparent plate 2 and small transparent plate 3. A pair of transparent plates (2 + 3) overlapped, the conductive fiber mesh 5 protruding outside the non-overlapping portions S1 to S4 and sandwiched between the two transparent plates 2 and 3, wider than the non-overlapping portions S1 to S4 A conductive tape 10a having a width and extending along the non-overlapping part S while projecting one end or both ends in the width direction from the non-overlapping parts S1 to S4 to cover the peripheral edge of the large transparent plate 2 Or 10b (see (B) and (C) in the same figure), the protruding portion of the conductive fiber mesh 5 and the conductive tape embedded in the steps of the transparent plates 2 and 3 along the non-overlapping portions S1 to S4. A strip-shaped conductive gasket 13 for surface-contacting the tape 10a or 10b , and the transparent plate pair 2, 3 is provided with a conductive frame 18 fitted into the transparent plate pair 2 and 3 and the conductive gasket 13 so as to be in close contact with the peripheral edge portion of 3 .

Preferably, as shown to FIG. 1 (A), the outer edge of the conductive fiber mesh 5 is made to protrude over the full width of the non-overlapping part S1-S4. The conductive fiber mesh 5 can be, for example, a black conductive fiber mesh in which fine irregularities are formed on the surface of a metal-coated mesh fabric and a black conductive coating is plated on the fine irregularities. Desirably, as shown in FIG. 2 (A), conductive tape 10a covering both the non-overlapping portions S1 to S4 and the peripheral portions of the transparent plates 2 and 3 by projecting both ends in the width direction from the non-overlapping portions S1 to S4. Is used . Alternatively, as shown in FIG. 2B, one end of the large transparent plate 2 is formed by extending one end in the width direction over the entire width on the non-overlapping portions S1 to S4 and projecting the other end in the width direction from the non-overlapping portions S1 to S4. You may use the conductive tape 10b which coat | covers a peripheral part.

More preferably, as shown in FIGS. 2 and 3, the large transparent plate 2 (thickness W2) is a thicker transparent plate than the small transparent plate 3 (thickness W3). As shown in FIG. 2A and FIG. 3A, the translucent electromagnetic wave shield plate 1 of the present invention has a conductive sash 20 into which the peripheral portion of the shield plate 1 is fitted, and the shield plate 1 and the sash 20. It is possible to include a conductive elastic member 23 or 24 that is embedded in a gap between the conductive elastic member 23 and the conductive elastic member 23 and 24.

The translucent electromagnetic wave shielding plate 1 of the present invention overlaps a large transparent plate 2 and a small transparent plate 3 having a similar shape with the non-overlapping portions S1 to S4 at the periphery, and both the transparent plates 2, 3, the conductive fiber mesh 5 is sandwiched while protruding the outer edge of the non-overlapping portions S <b> 1 to S <b> 4 over the entire space between the three, and the conductive tape 10 a or 10 b having a width wider than the non-overlapping portions S <b> 1 to S <b> 4 Alternatively, both ends protrude from the non-overlapping portions S1 to S4 and extend along the non-overlapping portion S while covering the peripheral edge of the large transparent plate 2, and both the transparent plates along the non-overlapping portions S1 to S4. A strip-shaped conductive gasket 13 is embedded in the two or three steps to bring the protruding portion of the conductive fiber mesh 5 into surface contact with the conductive tape 10a or 10b . Further, the conductive frame 18 is attached to the transparent plate pair 2, The transparent plate pairs 2 and 3 and the conductive gaskets are in close contact with the peripheral edge of 3 Because fitted 3 and the like are integrated, the following effects.

(A) Since the conductive fiber mesh 5 and the conductive tapes 10a and 10b are pressed and brought into surface contact with each other on the non-overlapping portions S1 to S4 on the periphery of the large transparent plate 2, the bending external force applied to the conductive fiber mesh 5 is It is possible to prevent the metal coating from being peeled down, and to obtain a light-transmitting shield plate 1 having a stable quality in terms of conductivity and shielding performance.
(B) Further, the outer edge of the conductive fiber mesh 5 protrudes over the entire width of the non-overlapping portions S1 to S4 , and the contact area between the mesh 5 and the conductive tapes 10a and 10b is increased as much as possible, thereby making the conductive fiber mesh 5 can be prevented from being deteriorated due to poor contact between the tape 5 and the conductive tapes 10a and 10b .
(C) By using the conductive fiber mesh 5 in which fine unevenness is formed on the surface and the black conductive coating is plated on the fine unevenness, the reflected light is reduced by light scattering of the unevenness and black light absorption. It can be set as the translucent electromagnetic wave shielding board 1 with high translucency.
(D) By embedding a strip-shaped conductive gasket 13 along the step between the two transparent plates 2 and 3, the translucent shield plate 1 can be connected to the outside through the gasket 13 as well as the conductive tapes 10 a and 10 b. be able to.
(E) By using the conductive tapes 10a and 10b covering the peripheral edge of the transparent plates 2 and / or 3, the translucent shield plate 1 can be easily manufactured or installed, and attached to and removed from the sash. An easy translucent shield plate 1 can be obtained.

FIG. 1 shows an embodiment of a translucent electromagnetic wave shielding plate 1 of the present invention in which a conductive fiber mesh 5 is sandwiched between a pair of similar large transparent plate 2 and small transparent plate 3. The transparent plates 2 and 3 in the illustrated example are respectively rectangular transparent glass or transparent resin plate. For example, when the center points are aligned and overlapped as shown in FIG. Band-shaped non-overlapping portions d1 to d4 (portions made only of the large transparent plate 2 that does not overlap the small transparent plate 2) S1 to S4 are formed. However, the shape of the transparent plates 2 and 3 is not limited to a rectangle, and may be a circle or a polygon. In addition, the conductive fiber mesh 5 in the illustrated example has substantially the same shape as the large transparent plate 2, and is overlapped with the large transparent plate 2 and sandwiched between the small transparent plate 3 so that the outer edge of the mesh 5 is not covered. The superimposing portions S1 to S4 are caused to protrude. The widths d1 to d4 of the non-overlapping portions S1 to S4 on the four sides are, for example, about 5 to 10 mm, but are appropriately determined in consideration of the contact area between the conductive strip 10 and the protruding portion of the mesh 5 described later. The widths d1 to d4 of the non-overlapping portions S1 to S4 may be slightly different.

An example of the conductive fiber mesh 5 is a mesh fabric obtained by plain weaving long fibers having a wire diameter of about 20 to 50 μm which are synthetic fibers such as polyester fibers and polyamide fibers or natural fibers such as silk at a density of about 50 to 300 / inch. In addition, a metal coating (for example, copper coating) is formed on the surface of the mesh fabric after weaving by an electroless plating method or the like. Preferably, a black conductive coating is provided on the metal coated surface of such a mesh fabric. For example, fine unevenness of about 0.1 to 1 μm is formed on the surface of a metal-coated mesh fabric by etching or uneven plating, and further black conductive coating (for example, black nickel zinc alloy is formed on the fine unevenness by plating. , Black nickel tin alloy, etc.) to form a black conductive fiber mesh 5. Alternatively, the surface of the metal-coated mesh fabric is oxidized to form fine irregularities, and the black conductive fibers are formed by forming a black conductive film on the irregular surface by an anti-migration process or an anti-rust film forming process. A mesh 5 can also be used. By forming fine irregularities on the surface of the conductive fiber mesh 5, the reflected light of the incident light can be scattered to provide antiglare properties. Further, by forming a black conductive coating on the uneven surface, light reflection can be suppressed without reducing the conductivity. The manufacturing method of such a conductive fiber mesh 5 is described in detail in Patent Document 7 and Patent Document 6. However, it is not an essential condition for the present invention to form fine irregularities on the surface of the conductive fiber mesh 5 (see Example 3 described later).

In the illustrated example, the mesh 5 and the large transparent plate 2 have substantially the same area so that the outer edge of the conductive fiber mesh 5 protrudes over the entire width of each of the non-overlapping portions S1 to S4. May be slightly smaller than the large transparent plate 2 or larger than the small transparent plate 3, and conversely, a part of the outer edge of the mesh 5 (for example, 10 to 20 mm) may protrude from the periphery of the large transparent plate 2. . As shown in FIG. 2A, the outer edge of the mesh 5 protruding from the periphery of the large transparent plate 2 is bent. However, as will be described later, in the present invention, the mesh 5 in the non-overlapping portions S1 to S4 is electrically conductive. Since sufficient electrical conductivity can be ensured by surface contact with the strip 10, there is no problem of reduced conductivity even if the metal coating on a part of the mesh 5 is peeled off at the bent portion.

Both the transparent plates 2 and 3 and the conductive fiber mesh 5 are respectively transparent adhesive layers (for example, between the transparent plates 2 and 3 and the mesh 5, for example, similarly to the conventional transparent electromagnetic wave shield plate 31 shown in FIG. 5. EVA adhesive layer or the like) can be provided and bonded together by a vacuum thermocompression bonding method or the like. Furthermore, the translucent electromagnetic wave shielding plate 1 of the present invention includes the conductive strip 10 extending along the non-overlapping portions S1 to S4 of the transparent plates 2 and 3 bonded together, and the non-overlapping portion S1. It has the pressing member 12 which presses to S4 and makes the protruding part of the mesh 5 and the strip | belt-shaped piece 10 surface-contact. The strip 10 is wider than the non-overlapping portions S1 to S4, and one end or both ends in the width direction are projected from the non-overlapping portions S1 to S4 as shown in the illustrated example.

For example, as shown in FIG. 2 (A), the conductive strip 10 has both ends in the width direction projecting on both sides of the non-overlapping portions S1 to S4, and the peripheral portions of the non-overlapping portions S1 to S4 and the transparent plates 2 and 3. It can be set as the electroconductive tape 10a which coat | covers. In the illustrated example, a conductive tape 10a such as a copper foil tape having conductivity is also used for the adhesive surface, and the conductive portion of the adhesive surface of the conductive tape 10a that protrudes to the non-overlapping portions S1 to S4. It sticks in contact with the fiber mesh 5, and the both ends in the width direction are bent and attached to the peripheral portion including the surfaces of the transparent plates 2 and 3 on both sides. The strip 10 is for electrically connecting the mesh 5 to the outside (for example, the conductive elastic members 23 and 24 in the figure) so that the peripheral edges of the transparent plates 2 and 3 are covered to the surface as shown in the illustrated example. It is desirable to use a sufficiently wide conductive tape 10a.

Alternatively, as shown in FIG. 2B, the conductive strip 10 is extended with one end in the width direction overlapped with the non-overlapping portions S1 to S4 and the other end in the width direction is projected from the non-overlapping portions S1 to S4. It is good also as the electroconductive tape 10b which coat | covers the peripheral part of the large transparent board 2. FIG. For example, one end in the width direction of the conductive tape 10b is inserted between the conductive fiber mesh 5 that protrudes into the non-overlapping portions S1 to S4 and the large transparent plate 2, and the adhesive surface is not overlapped with the transparent plate 2. The non-adhesive surface is attached to the part S and brought into contact with the mesh 5, and the other end in the width direction is bent to cover the peripheral part including the surface of the transparent plate 2. Thus, when making the non-adhesion surface of the electroconductive tape 10b contact the mesh 5, the electroconductivity of the adhesion surface of the electroconductive tape 10b is not required. Further, as compared with the case where the conductive tape 10a and the mesh 5 are brought into contact with each other through an adhesive surface having a relatively low conductivity as shown in FIG. According to the configuration of FIG. 2B in which the adhesive surface is brought into contact with the mesh 5, high conductivity between the conductive tape 10b and the mesh 5 can be ensured. When the conductive tape 10a and the mesh 5 are brought into contact with each other through the adhesive surface, it is necessary to press the two with a large pressing force in order to ensure conduction, and there is a risk of damaging the mesh 5, but FIG. According to the configuration of B), the conductive tape 10b and the mesh 5 can be reliably conducted with a relatively small pressing force, and the risk of damage to the mesh 5 is eliminated.

Preferably, as shown in FIG. 2C, the conductive strip 10 is constituted by both of the conductive tapes 10a and 10b. In the illustrated example, the conductive tape 10b provided in the same manner as in FIG. 2 (B) is brought into contact with the mesh 5 to conduct both, and the non-overlapping portion S1 is formed by the conductive tape 10a disposed in the same manner as in FIG. 2 (A). The mesh 5 is sandwiched and fixed between the conductive tapes 10a and 10b by covering S4 and the peripheral portions of the transparent plates 2 and 3. In this case, the conductive tape 10a having a conductive adhesive surface may be used as in FIG. 2A, but the mesh 5 is electrically connected to the non-adhesive surface of the conductive tape 10b. The conductivity of the adhesive surface 10a may not be present. By covering the mesh 5 (see FIG. 2B) exposed on the surface of the conductive tape 10b with the conductive tape 10a as in the illustrated example, there is no risk of the mesh 5 being damaged by the pressing member 12 to be described later. The easy handling of the conductive shield plate 1 and the quality stability of the shielding performance can be enhanced.

The pressing member 12 presses the protruding portion of the conductive fiber mesh 5 and the conductive strip 10 against the non-overlapping portions S1 to S4 of the large transparent plate 2 to bring them into surface contact. As shown, it can be set as the strip | belt-shaped gasket 13 embedded in the level | step difference of both the transparent plates 2 and 3 along the non-overlapping part S1-S4. By pressing the strip 10 on a part of the mesh 5 with the non-overlapping portions S1 to S4 and making it conductive, there is no need to bend the mesh 5 as shown in FIG. 5, and the external force applied to the mesh 5 is suppressed to a small level. Peeling can be prevented. Preferably, the pressing member 12 is a conductive gasket 13, and the mesh 5 is electrically connected to the outside (for example, the conductive elastic member 23 in the figure) through the gasket 13 as well as the conductive strip 10. However, the pressing member 12 is not limited to the gasket 13, and is inserted into and fixed to the through holes 2a provided in the non-overlapping portions S1 to S4 of the large transparent plate 2, for example, as shown in FIG. The bolt 16 to be used may be the pressing member 12.

In the embodiment of FIG. 2 (B), in order to prevent a lateral displacement or the like between the conductive fiber mesh 5 and the conductive strip 10 (conductive tape 10b) when the pressing member 12 is pressed, After the mesh 5 and the strip 10 are pasted by the plate material 14 with the adhesive 15, the pressing member 12 is pressed onto the plate material 14. By preventing a lateral shift between the mesh 5 and the strip 10, the external force applied to the mesh 5 can be further reduced. However, such a plate material 14 is not essential to the present invention. For example, when the strip 10 (conductive tape 10a) is attached to the mesh 5 as shown in FIG. The plate material 14 can be omitted because a lateral shift or the like with the belt-like piece 10 hardly occurs.

Moreover, as shown in FIG. 2, in order to give sufficient intensity | strength to the non-overlapping part S1-S4 which presses the press member 12, it is desirable to make the large transparent board 2 into sufficient thickness. The thicknesses W2 and W3 of the large and small transparent plates 2 and 3 need to be determined in accordance with the overall thickness of the translucent electromagnetic wave shielding plate 1, but the large pressing force of the pressing member 12 is taken into consideration. It is desirable to make the thickness W2 of the large transparent plate 2 relatively larger than the thickness W3 of the small transparent plate 3 (W2> W3). For example, the thickness W2 of the large transparent plate 2 is set to the thickness of the small transparent plate 3. W3 is 1.5 to 3 times, preferably about 2 times.

FIG. 2A shows a method of attaching the translucent electromagnetic wave shielding plate 1 of the present invention to the sash 20 (see FIG. 4). In the illustrated example, a metallic sash 20 that conducts to the surrounding floor or the like is used, and the shield plate 1 is placed on the setting block 22 in the sash 20, and then the conductive strip 10 and the pressing member of the shield plate 1. By embedding a conductive elastic member 23 such as a conductive backer between the sash 20 and the sash 20, the pressing member 12 is pressed against the non-overlapping portions S1 to S4 of the transparent plate 2, and the strip 10 (and the conductive The conductive fiber mesh 5 and the sash 20 are conducted through the pressed member 12). Alternatively, instead of or in addition to the conductive elastic member 23, a conductive elastic member 24 such as a conductive tube is embedded between the shield plate 1 and the sash 20 as shown in the figure, and the elastic member 24 and the belt-like deformation 10 are embedded. The mesh 5 and the sash 20 may be electrically connected via each other.

The translucent electromagnetic wave shielding plate 1 of the present invention brings the conductive fiber mesh 5 and the conductive strip 10 into surface contact at the non-overlapping portions S1 to S4 on the periphery of the large transparent plate 2, and the strip 10 is not overlapped. Since it protrudes from the parts S1 to S4 and comes into contact with the outside (for example, the conductive elastic members 23 and 24 in FIG. 2A), it is possible to suppress the bending external force applied to the mesh 5 and prevent the metal coating from peeling off. It can be set as the translucent shield board 1 with the quality of shield performance stable.

Thus, the “translucent electromagnetic wave shielding plate having a stable quality using the conductive fiber mesh” which is an object of the present invention can be provided.

Preferably, the transparent electromagnetic wave shielding plate 1 of the present invention is pressed against the transparent plate pairs 2 and 3 in close contact with the peripheral portions of the transparent plate pairs 2 and 3 as shown in FIGS. A conductive frame 18 that integrates the member 12 is included. As shown in FIG. 4A, the conductive frame 18 is fitted around the periphery of the shield plate 1 to bring the conductive strip 10 (and the pressing member 12 made conductive) into contact with the frame 18. By simply fitting the frame 18 of the shield plate 1 into the sash 20 and embedding the conductive elastic members 23 and 24 between them, fixing of the shield plate 1 and securing of electrical conductivity can be achieved simultaneously. The handling of the shield plate 1 and the construction of the electromagnetic wave seal space using the shield plate 1 can be facilitated. Further, the shield plate 1 provided with the frame 18 on the periphery can be easily detached from the sash 20 in accordance with the change in the layout of the electromagnetic wave seal space and can be reused. Can increase the sex. When the conductive frame 18 is fitted, it is desirable to insert or fill a gap filling material 18a between the shield plate 1 and the frame 18 to prevent intrusion of water or the like.

FIG. 3C shows a plurality of through-holes 2a penetrating the transparent plate 2 in the thickness direction along the non-overlapping portions S1 to S4 of the large transparent plate 2, and the peripheral edge surface of the large transparent plate 2 and A conductive frame 19 having an L-shaped cross section with a through-hole that is in close contact with the surface is fitted, and the bolt 16 inserted from the non-overlapping portions S1 to S4 of the transparent plate 2 is inserted into the through-hole 2a of the transparent plate 2 and the frame 19. An embodiment in which the protruding portion of the conductive fiber mesh 5 of the non-overlapping portions S1 to S4 and the conductive strip 10 are brought into surface contact by fixing with the nut 17 is shown. In this case, the pressing member 12 is constituted by the bolt 16 and the nut 17. Further, in this case, as in the example shown in the figure, the lateral displacement or the like is not generated between the conductive fiber mesh 5 and the conductive strip 10 when the bolt 16 is pressed, as in the case of FIG. It is desirable that the mesh 5 and the strip 10 are attached in advance to the plate material 14 with the adhesive 15 and the bolts 16 are inserted through the through holes of the plate material 14.

A copper coating is provided on the surface of a mesh fabric woven from polyester monofilaments with a fineness of 8 dtex at a weaving density of 132 pieces / inch by electroless plating, and fine unevenness is formed on the surface of the copper coating by uneven plating treatment. A translucent electromagnetic wave shielding plate 1 according to the present invention was prototyped using a black conductive fiber mesh 5 plated with a black nickel zinc alloy. In this experiment, the conductive fiber mesh 5 is interposed between a pair of large transparent glass 2 (thickness W2 = 8 mm) and small transparent glass 3 (thickness W3 = 4 mm) via an EVA adhesive layer (400 μm). The shield plate 1 was created by sandwiching and bonding by vacuum thermocompression bonding. The length of one side of the large transparent glass 2 was made 1 cm larger than that of the small transparent glass 3, and a band-shaped non-overlapping portion S having a width of 5 mm was provided on the periphery of the pair of glasses 2 and 3 to give a step. The size of the conductive fiber mesh 5 was determined so that the outer edge protruded 18 mm from the periphery of the large transparent glass 3.

As shown in FIG. 3 (A), a conductive tape 10a covering the non-overlapping portion S and the peripheral portions of both transparent glasses 2 and 3 was used as the conductive strip 10 and protruded into the non-overlapping portion S. The conductive fiber mesh 5 was fixed to the large transparent glass 2 and the small transparent glass 3 on both sides with a conductive tape 10a. Further, the transparent gasket 2 and 3 and the conductive gasket 12 are integrated by pressing the conductive gasket 12 from above the conductive tape 10a and fitting the conductive frame 18 on the outside thereof. An electromagnetic wave shielding plate 1 was obtained. The shield plate 1 was fitted into the metallic sash 20 in the electromagnetic wave shielding space, and the shield plate 1 and the sash 20 were fixed by embedding the electric packer 23 and the conductive tube 24 in the gap between the shield plate 1 and the sash 20. After fixing the shield plate 1 and measuring the shielding performance and translucency in the shielding space, a shielding effect of 100 dB or more for electromagnetic waves of 10 to 150 MHz and a transmissivity of 50% or more for visible light can be obtained. It was confirmed that the performance was as expected. From this, it was confirmed that the metal coating of the conductive fiber mesh 5 was not peeled off in the transparent shield plate 1 of the present invention.

The surface of the mesh fabric coated with copper as in Example 1 is oxidized to form fine irregularities, and the surface of the irregularities is subjected to migration prevention treatment or antirust coating formation treatment (see Patent Document 6). A translucent electromagnetic wave shielding plate 1 of the present invention was prototyped using a matte black conductive fiber mesh 5 with a coating formed thereon. As in Experimental Example 1, the black conductive mesh 5 is sandwiched between a pair of large transparent glass 2 (thickness 8 mm) and small transparent glass 3 (thickness 4 mm), and bonded together by a vacuum thermocompression bonding method. The shield plate 1 is formed, and the conductive fiber mesh 5 that protrudes into the non-overlapping portion S as shown in FIG. 3A is fixed to the transparent glasses 2 and 3 with the conductive tape 10a and on the conductive tape 10a. A conductive gasket 12 was pressed, and a conductive frame 18 was fitted on the outer side thereof to obtain a translucent electromagnetic wave shielding plate 1. When this shield plate 1 was fixed to the sash 20 in the electromagnetic wave shielding space in the same manner as in Experimental Example 1 and the shielding performance and translucency were measured, the same shielding performance and translucency as in Example 1 were obtained. It was confirmed that both performances were as designed. From this, even when unevenness is formed by performing an oxidation treatment on the copper coating surface, the metal coating of the conductive fiber mesh 5 is not peeled off by the transparent shield plate 1 of the present invention, and the conductivity is maintained. It could be confirmed.

Furthermore, a copper conductive coating is provided on the surface of a mesh woven fabric of polyester monofilament having a fineness of 13 dtex at a weaving density of 135 / inch, and a black conductive fiber plated with black nickel tin alloy without forming fine irregularities on the surface of the copper coating. A light-transmitting electromagnetic wave shielding plate 1 of the present invention was prototyped using a mesh 5. As in Experimental Example 1, the black conductive mesh 5 is sandwiched and bonded between the transparent glasses 2 and 3, and the conductive fiber mesh 5 protruding to the non-overlapping portion S is transparent glass 2 with the conductive tape 10 a. 3, the conductive gasket 12 was pressed onto the conductive tape 10 a, and the conductive frame 18 was fitted on the outer side to form the translucent electromagnetic wave shielding plate 1. When this shield plate 1 was fixed to the sash 20 in the electromagnetic wave shielding space in the same manner as in Experimental Example 1 and the shielding performance and translucency were confirmed by experiments, the appearance was slightly reduced compared to the shielding plate 1 of Example 1. However, almost the same shielding performance and translucency were obtained, and it was confirmed that both performances were as designed. From this, it was confirmed that even when the conductive fiber mesh 5 having no fine irregularities formed on the surface was used, it was possible to prevent peeling of the metal coating of the conductive fiber mesh 5 by the transparent shield plate 1 of the present invention.

It is explanatory drawing of one Example of the translucent shield board of this invention. It is an example of the vertical sectional view which shows the structure of the non-overlapping part of the translucent shield board of this invention. It is another example of the vertical sectional view which shows the structure of the non-overlapping part of the translucent shield board of this invention. It is explanatory drawing of the electromagnetic wave shield wall which combined the translucent shield board and the translucent magnetic shield housing. It is explanatory drawing of an example of the conventional translucent shield board.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Translucent electromagnetic wave shield board 2 ... Large transparent board 2a ... Through-hole 3 ... Small transparent board 5 ... Conductive fiber mesh 10 ... Conductive strip 10a, 10b ... Conductive tape 12 ... Pressing member 13 ... Conductivity Gasket (or packing)
DESCRIPTION OF SYMBOLS 14 ... Plate material 15 ... Adhesive 16 ... Bolt 17 ... Nut 18 ... Conductive frame 18a ... Gap filling material 19 ... Conductive frame 20 ... Conductive sash 21 ... Push edge 22 ... Setting block 23 ... Conductive elastic member (Packer)
DESCRIPTION OF SYMBOLS 24 ... Conductive elastic member (tube) 25 ... Supporting protrusion 26 ... Mesh structure conductor 27 ... Backup material 28 ... Sealing material 29 ... Conductive coating 31 ... Translucent electromagnetic shielding plate 32 ... Transparent plate 33 ... Transparent plate 34 ... Conductive mesh 35 ... Adhesive layer 36 ... Adhesive layer 37 ... Conductive coating material (conductive tape) 39 ... Joint member 39a ... Supporting protrusion 40 ... Magnetic shield housing 41 ... Magnetic plate S ... Non-overlapping part d ... Non Overlap width

Claims (7)

A pair of transparent plates in which a large transparent plate of similar shape and a small transparent plate are overlapped at the periphery, leaving a strip-like non-overlapping part, and the outer edge protrudes into the non-overlapping part and is sandwiched between the two transparent plates. The conductive fiber mesh has a width wider than the non-overlapping part and extends along the non-overlapping part while covering one edge or both ends in the width direction from the non-overlapping part to cover the peripheral edge of the large transparent plate. A conductive tape , a strip-shaped conductive gasket embedded in the steps of both transparent plates along the non-overlapping portion and in contact with the conductive tape and the conductive tape , and the transparent tape. A light- transmitting electromagnetic wave shielding plate comprising a conductive frame that is fitted in close contact with a peripheral portion of a plate pair so that the transparent plate pair and the conductive gasket are integrated . 2. The light-transmitting electromagnetic wave shielding plate according to claim 1, wherein an outer edge of the conductive fiber mesh protrudes over the entire width of the non-overlapping portion. 3. The shield plate according to claim 1 or 2, wherein the conductive fiber mesh is a black conductive fiber mesh in which fine irregularities are formed on the surface of a metal-coated mesh fabric, and a black conductive coating is plated on the fine irregularities. Translucent electromagnetic shielding plate. 4. The shield plate according to claim 1, wherein the conductive tape is formed as a conductive tape that protrudes at both ends in the width direction from the non-overlapping portion and covers the non-overlapping portion and the peripheral portions of both transparent plates. Translucent electromagnetic shielding plate. The shield plate according to any one of claims 1 to 3, wherein the conductive tape has a large transparent portion with one end in the width direction extending over the entire width on the non-overlapping portion and the other end in the width direction protruding from the non-overlapping portion. A light-transmitting electromagnetic wave shielding plate as a conductive tape covering the peripheral edge of the plate. 6. The light-transmitting electromagnetic wave shielding plate according to claim 1 , wherein the large transparent plate is a thicker transparent plate than the small transparent plate. The shield plate according to any one of claims 1 to 6 , further comprising a conductive sash that fits a peripheral portion of the electromagnetic wave shield plate, and a conductive elastic member that is buried in a gap between the shield plate and the sash to make both conductive. A translucent electromagnetic wave shielding plate.

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