JPH0685473B2 - Electromagnetic wave shielding multilayer transparent body - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electromagnetic wave shielding multilayer transparent body having excellent electromagnetic wave shielding performance and suitable for use in windows, doors and the like.

[Prior Art] In recent years, noise due to electromagnetic waves has become a serious problem in buildings and various other buildings. As a measure against such electromagnetic noise, in order to prevent equipment inside the building from being disturbed by external electromagnetic noise, we have developed technology to prevent external electromagnetic waves from entering the building and affect other buildings with electromagnetic waves. To prevent this, there is a demand for the development of technology that does not emit electromagnetic waves from inside the building to the outside. In particular, noise generation and malfunctions occur in intelligent buildings, computer centers, buildings that use precision electronic equipment, offices, hospitals, etc., where information network systems such as optical fiber cables, coaxial cables, or wireless communication are spread throughout the building. In order to prevent information leakage or wiretapping of information, there is a need for a technology that does not emit electromagnetic waves and a technology that does not allow electromagnetic waves, and it is expected that the need will increase even more in the future. Further, in a place where the electromagnetic environment is bad, such as a train or a high-voltage power transmission line, there is a demand for an electromagnetically shielded building that does not allow electromagnetic waves to enter.

When building such a building that does not let in or does not emit such electromagnetic waves, various buildings, offices, etc., there are openings such as windows and entrances and exits at the site where the electromagnetic wave shielding performance is required most. However, in the past, materials for openings such as windows or doorways, in particular, materials for windows and openings such as glass, which are required to be transparent, have no electromagnetic wave shielding performance, and therefore electromagnetic wave shielding cannot be performed. . Therefore, until now, a building with a high degree of electromagnetic wave shielding performance is a building without windows,
The sunlight was not coming in and the work environment was not favorable. Alternatively, in a normal building, if a space that shields electromagnetic waves is required, it is necessary to create an electromagnetic wave shielded room without a window in the building or in the room, and in this case also there are the disadvantages described above. . From this point of view, it has been required to develop a transparent material such as glass having a high electromagnetic wave shielding performance and a sufficient transmission performance in the visible light region of sunlight.

BACKGROUND ART Conventionally, a window glass having a high electromagnetic wave shielding performance and having a transmission performance in the visible light range of sunlight has a cloth-like shape woven by fine wires having a high electromagnetic wave shielding performance, for example, two mesh cloths. It is something that is sandwiched between glass plates, or one that attaches a large metal film to the glass surface.The former is not satisfactory in terms of electromagnetic wave shielding performance, and it is not visible in the sunlight. There is a problem in the transparency of the light range.
In addition, the latter has a drawback that it has a big problem in the transmittance of sunlight in the visible light region.

[Problems to be Solved by the Invention] The present invention does not have the drawbacks described above, has a high electromagnetic wave shielding performance, and a transparent material such as glass having a sufficient visible light transmission performance of sunlight, Buildings that shield electromagnetic waves,
It is an object of the present invention to provide a transparent body suitable for use in openings such as windows and doorways of buildings and rooms.

[Means for Solving Problems] The present invention has been invented based on the above-mentioned object,
The gist thereof is that at least one transparent plate of the above-mentioned transparent plate of a multi-layer transparent body is formed by holding a plurality of transparent plates facing each other with a space provided therebetween, and forming an inner hollow layer between the transparent plates by hermetically sealing the periphery. The present invention relates to an electromagnetic wave shielding multilayer transparent body, wherein a transparent conductive film is formed on a plate surface, and a grid, at least a part of which is a good electric conductor, is provided in the inner hollow layer.

[Examples] Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially omitted schematic illustration of an electromagnetic wave shielding multilayer transparent body according to the present invention, wherein 1 is a multilayer transparent body, 2 and 3 are transparent plates, 4
Indicates an inner hollow layer, 5 indicates a transparent conductive film, and 6 indicates a lattice which is a good electric conductor. In the multi-layer transparent body 1, two transparent plates 2 and 3 are spaced at a predetermined interval in parallel with each other by a spacer 7 containing a desiccant arranged in the periphery thereof, and a sealant 8 is arranged in the peripheral portion of the transparent plate 2 and 3 for sealing. However, the inner hollow layer 4 is provided between the two transparent plates 2 and 3. As the transparent plate in this multilayer transparent body, a transparent, translucent, colored transparent, or colored translucent glass plate or various plastic plates can be used. Among them, the glass plate has optical characteristics and durability. It is preferable from the points such as. The multi-layer structure type of the multi-layer transparent body is not limited to the type shown in FIG. 1, but as shown in FIG. 2, a window frame 9 in which two transparent plates 2 and 3 are arranged in the periphery thereof. According to the above, types of those spaced in parallel with each other so as to provide an internal hollow layer having a predetermined width, or types similar to these can also be used.
The above example shows a multi-layer transparent body using two transparent plates, but one or two transparent plates may be added to form a three-layer or four-layer structure. You can also

In the multilayer transparent body of the present invention, a transparent conductive film is formed on at least one of the transparent plates 2 and 3 constituting the multilayer transparent body. Examples of the transparent conductive film include a transparent tin oxide conductive film (tin oxide conductive film doped with antimony or fluorine) and a transparent indium oxide conductive film (indium oxide conductive film doped with tin). , Cr, Ti,
A single-layer thin film type of a transparent metal or a transparent alloy such as Ag, Au, Al, Cu, Ni, etc., or these transparent metals are, for example, ZnO, SnO ₂ , In ₂ O ₃ , TiO ₂ , Ta ₂ O ₅ , Bi
Multi-layer thin film type sandwiched from the top and bottom with thin films of ₂ O ₃ , WO ₃ , ZnS, etc., eg TiO ₂
Film / Ag film / TiO ₂ film, ZnO film / Ag film / ZnO film, SnO ₂ film / Ag film / Sn
3-layer type such as O ₂ film, TiO ₂ film / Ag film / TiO ₂ film / Ag film / Ti
A five-layer type such as an O ₂ film, a ZnO film / Ag film / ZnO film / Ag film / ZnO film, or any other suitable structure can be used. These transparent conductive films are illustrated as examples in which those having a property of high heat ray reflectivity are illustrated, but a film having a property of relatively low heat ray reflectivity other than the above is used as necessary. You can also When the transparent conductive film is formed using a film having a high heat ray reflectivity, it can also be used as a window material having a cooling and heating load reducing function and a high heat insulating property.

Further, the transparent conductive film having the above-mentioned structure can be formed by using an appropriate film forming method such as a vacuum vapor deposition method, a sputtering method, a CVD method, a spray method, a CLD method, and a print printing method. In this case, the transparent conductive film is preferably formed by directly laminating it on the transparent plate surface. For example, a transparent conductive plastic formed by laminating the transparent conductive film on a plastic film surface such as polyester film. It is also possible to use the film as a transparent conductive film and stack it on a transparent plate for use.

The transparent conductive film used in the present invention preferably has a sheet resistance of 20 Ω / □ or less so that a high electromagnetic wave shielding effect can be obtained. In particular, it is optimal to be 10Ω / □ or less so that electromagnetic waves in a wide high frequency region of 400MHz or more can be effectively shielded. The film thickness of the transparent conductive film is appropriately determined so that the desired resistance value and the desired visible light transmittance as described above can be obtained and a desired color tone can be obtained.

The transparent conductive film may be formed on at least one transparent plate surface of the multilayer transparent body, and may be formed on only one transparent plate, or two or more transparent plates. You may form in a board. Further, the transparent conductive film formed on one or more transparent plates may be of a type divided into two or more, and may be composed of a plurality of transparent conductive films. In this case, the distance between the transparent conductive films is preferably 1 cm or less so that electromagnetic waves do not leak. When a plurality of transparent conductive films are formed on one transparent plate in this manner, they are electrically connected in parallel to
The electric resistance value of the plurality of transparent conductive films formed on one transparent plate can be reduced, and the electromagnetic wave shielding performance can be improved.

The surface of the transparent plate on which the transparent conductive film is formed may be the inner hollow layer side of the multilayer transparent body, the outdoor side surface, or the indoor side surface. When the durability of the transparent conductive film is not sufficient, it is advantageous to use the transparent plate on the inner hollow layer side from the viewpoint of durability.

Further, as the grid provided in the inner hollow layer of the multilayer transparent body of the present invention, a grid of a good electric conductor is used so as to shield electromagnetic waves. The grid of the good electrical conductor may be a grid made of a metal or an alloy of the good electrical conductor (for example, Al, Cu, stainless steel, brass, etc.) or other conductive material, or a grid made of plastic or the like. It may be a grid formed by forming a coating layer of a metal or alloy of a good electric conductor or other conductive substance on the surface, or a grid of a metal or alloy of a good electric conductor, or another conductive substance. Configure
The surface may be coated with an insulating layer or an insulating layer. The front shape of the lattice of each unit of this lattice is not particularly limited, and may be a triangle, a quadrangle, a pentagon, a hexagon,
Other various arbitrary shapes can be adopted. The longer length (inner dimension) of the diagonal line of the lattice of each unit is determined from the viewpoint of desired translucency, electromagnetic wave shielding performance, design and the like. Generally, it is suitable that the lengths of the diagonal lines are 1 cm to 30 cm, respectively.

If it is larger than 30 cm, the electromagnetic wave shielding performance in the low frequency band is deteriorated, which is not preferable, and if it is smaller than 1 cm, the lattice pattern becomes dense and it is not preferable from the viewpoint of transparency and light transmission.

By using a grid of an electric conductor having the above-described structure and dimensions, it is possible to effectively shield the electromagnetic wave by repeating the reflection of the electromagnetic wave on each grid surface. In particular, it is possible to effectively shield electromagnetic waves on a lower frequency side, for example, electromagnetic waves of 400 MHz or less.

The example shown in FIG. 1 is for a metal grid made of aluminum whose unit grid shape is a square. By setting the diagonal length to 5 cm to 15 cm, 400MH
It is designed to shield electromagnetic waves below z.

In the electromagnetic wave shielding multilayer transparent body of the present invention, the transparent conductive film and the grid of a good electrical conductor may be in a conductive state. However, if the transparent conductive film is an electromagnetic wave in a higher frequency range (for example,
A transparent conductive film and a grid of a good electrical conductor are formed of at least a transparent conductive film so that the high frequency band of 300 MHz or more) and the low frequency electromagnetic wave (for example, 400 MHz or less) can be effectively shielded by the grid. It is more preferable that the formed transparent plate has a non-conductive state in the central region thereof. In this case, in the peripheral portion of the transparent plate, the transparent conductive film and the grid of the good electrical conductor may be in a conductive state. In order to bring the transparent conductive film and the grid of a good electrical conductor into a non-conducting state, an electrically insulating layer may be formed between at least the contacting portions of the two, or they may be separated from each other so that they are not conducting. You may make it a state. Alternatively, it is also possible to bring both of them into a non-conducting state by selecting the surface on which the transparent conductive film is formed as a surface that is not in contact with the grid of the good electrical conductor.

At least one of the transparent conductive film and the electrically conductive grating should be provided with a ground connection end for ground so that the electromagnetic waves incident on these are dropped to the ground and electromagnetic wave shielding performance is exerted. it can. When the transparent conductive film and the grid are in the non-conducting state, the ground connection ends are provided separately, and when the conductive film is in the conducting state, the ground connection ends are provided separately or in one of them. In a transparent conductive film, a conductive paste containing a conductive metal powder such as Ag or Al is usually printed and printed on an appropriate peripheral portion on the surface of the transparent conductive film in a predetermined pattern and baked or cured to form a busbar. Or, or form a bus bar by pasting a predetermined pattern of Al foil or Cu foil,
An earth connection end is provided at an appropriate position on this bus bar. If desired, a terminal can be attached to this ground connection end to facilitate the connection of the ground wire.

The transparent conductive film does not necessarily have to be provided with a ground connection end. For example, when a predetermined part of the transparent conductive film is exposed and the transparent body is attached to the sash or the like, a conductive sealant is arranged on the exposed part of the transparent conductive film, and the conductive sealant is used to establish conduction with the sash. You may Further, in the electrically conductive grid, the ground connection end is provided at an appropriate position in the peripheral portion of the grid, either directly or through a connecting metal fitting. This ground connection end may be provided at one place or at a plurality of places.

3 to 6 are cross-sectional views of a multilayer transparent body having a transparent conductive film 5 according to another embodiment of the present invention and a grid 6 which is a good electric conductor, and FIG. This is an example in which transparent conductive films 5 are formed on both sides of the inner hollow layer 4 of the transparent plates 2 and 3 and are separately grounded. 5 is an example in which the conductive conductive film 5 is formed and is grounded separately. In FIG. 5, the transparent conductive film 5 is formed on the side surface of the inner hollow layer 4 of the transparent plate 3 on the indoor side. It is an example of dropping to the ground,
Further, FIG. 6 shows an example in which the transparent conductive film 5 is formed on the indoor side surface of the transparent plate 3 on the indoor side, and they are separately grounded.

[Operation] According to the present invention, since the transparent conductive film is formed on the inner hollow layer side of the transparent plate constituting the multi-layer transparent body, and the grid, which is a good electric conductor, is provided in the inner hollow layer, A high electromagnetic wave shielding effect can be obtained by the actions of both the transparent conductive film and the lattice. In particular, the transparent conductive film has a high shielding performance against electromagnetic waves of high frequency of 300 MHz or more, and the grid, which is a good conductor, is 400M.
Since it has a high shielding performance for electromagnetic waves of low frequency below Hz, by using a combination of a transparent conductive film and a lattice, it radiates to the surroundings from computers, word processors, measuring instruments, robots, and other electronic devices to which various digital technologies are applied. It is possible to effectively shield an electromagnetic wave in a frequency range that operates, and an electromagnetic wave in a frequency range that malfunctions or adversely affects various electronic devices and information networks, for example, an electromagnetic wave in a wide band of 10 MHz or more.

Further, the electromagnetic wave shielding multilayer transparent body of the present invention has transparency and the periphery of the transparent plate is sealed, and since the inner hollow layer is formed, the sound insulating effect is high and the heat insulating effect is high. It is possible to save the heating energy, and also to suppress the inflow of outdoor heat even in the summer so that the cooling load can be reduced. Furthermore, since the transparent conductive film usually also has infrared reflection performance, by utilizing its characteristics,
It has the effect of suppressing the inflow of heat rays of sunlight into the room in the summer and the outflow of heat in the room in the winter, and is useful as a multifunctional glass.

The electromagnetic wave shielding multilayer transparent body of the present invention is required to have transparency, translucency, and a high electromagnetic wave shielding performance, such as an intelligent building or computer center, a building in which precision electronic devices are used, office, hospital or It is also useful as a window glass for various other buildings.

[Brief description of drawings]

FIG. 1 is a partially omitted schematic explanatory view of an electromagnetic wave shielding multilayer transparent body according to a specific example of the present invention, and FIGS. 2 to 6 are partial sectional views of electromagnetic wave shielding multilayer transparent bodies according to other specific examples. Indicates. 1; multilayer transparent body, 2, 3; transparent plate, 4; internal hollow layer, 5; transparent conductive film, 6; lattice

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-62-230098 (JP, A) Actually opened 60-176596 (JP, U) Actually opened 60-183497 (JP, U)

Claims (3)

[Claims] 1. At least one of the transparent plates of a multi-layered transparent body, wherein a plurality of transparent plates are held facing each other with a space provided therebetween, and an inner hollow layer is formed between the transparent plates by hermetically sealing the periphery. An electromagnetic wave shielding multilayer transparent body, characterized in that a transparent conductive film is formed on the surface of a transparent plate, and a grid, at least a part of which is a good electric conductor, is provided in the inner hollow layer. 2. The electromagnetic wave shield according to claim 1, wherein the transparent conductive film formed on the side surface of the inner hollow layer of the transparent plate and the lattice in the inner hollow layer are in a non-conductive state. Multi-layer transparent body. 3. An electromagnetic wave shielding multilayer transparent body according to claim 1, wherein a ground connection end is provided on at least one of the transparent conductive film and the grid.