JPH0719994B2 - Electromagnetic wave shielding transparent plate - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electromagnetic wave shielding transparent plate 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 countermeasure against such electromagnetic noise, in order to prevent equipment inside the building from being damaged by external electromagnetic noise, we have developed technology that does not allow external electromagnetic waves to enter the building and affect other buildings by 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 in intelligent buildings, computer centers, buildings that use precision electronic devices, offices, hospitals, etc., where information network systems such as optical fiber cables, coaxial cables, or wireless communication are installed in buildings. From the standpoint of preventing 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 the need is expected to increase 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 performance of transmitting visible light of sunlight, Buildings that shield electromagnetic waves,
It is an object of the present invention to provide a transparent plate 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 a transparent plate, wherein a transparent conductive film and a conductive grid pattern are formed on the transparent plate, and the transparent conductive film and the conductive grid pattern are formed on the transparent plate. Relates to an electromagnetic wave shielding transparent plate, which is provided in a non-conducting state without a contacting portion.

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

1 and 6 to 9 are cross-sectional views of the electromagnetic wave shielding transparent plate according to the present invention, and FIGS. 2 to 5 are plan views of the electromagnetic wave shielding transparent plate according to the present invention. In the figure, 1 is an electromagnetic wave shielding transparent plate, 2, 3 and 4 are transparent plates, 5 and 6 are transparent conductive films, 7, 8 and 9 are conductive lattice patterns, 10 is a laminated interlayer film, and 11 is a multilayer. Spacer 12 for the inner hollow layer.

As the transparent body in the present invention, a transparent, semi-transparent, colored transparent or colored semi-transparent glass plate or various plastic plates can be used. Among them, the glass plate is preferable from the viewpoint of optical characteristics and durability. This transparent plate is
The transparent plate 2 may consist of one sheet as shown in FIGS. 1 and 6, or a combined type in which two transparent plates 2 and 4 are joined by an intermediate interlayer 10 as shown in FIG. It is also possible to use two transparent plates 2 and 4 with spacers 10 as shown in FIGS. 8 and 9.
A multi-layer type in which the inner hollow layers 12 are spaced apart from each other by a predetermined distance so that the inner hollow layers 12 are formed, or two transparent plates are arranged at a predetermined distance from each other so that the inner hollow layers can be formed by a frame body. It may be of a double type which is spaced apart. Alternatively, the transparent plate may be a laminated type in which three or more transparent plates are joined by a laminated interlayer film, or may be a multi-layer type in which three or more transparent plates are separated by a spacer. However, it may be a multiple type in which three or more transparent plates are separated by a frame.

In the present invention, the transparent conductive film formed on the transparent plate is, for example, a transparent tin oxide conductive film (tin oxide conductive film with antimony or fluorine boping) or a transparent indium oxide conductive film (tin-doped film). Indium oxide conductive film), etc., as well as single layer thin film type made of transparent metal or transparent alloy such as Cr, Ti, Ag, Au, Al, Cu, Ni,
Alternatively, these transparent metals may be used as, for example, ZnO, SnO ₂ , In _{2
O 3, TiO 2, Bi 2} O 3, Ta 2 O 5, WO 3, a multilayer thin film type comprising sandwiching a sandwich from above and below by a thin film made of ZnS, for example, TiO ₂ film / Ag film / TiO ₂ film , ZnO film / Ag film / ZnO
Film, 3-layer type such as SnO ₂ film / Ag film / SnO ₂ film, TiO ₂ film / Ag
Film / TiO ₂ film / Ag film / TiO ₂ film, ZnO film / Ag film / ZnO film / Ag film / ZnO
A five-layer type such as a 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 40MHz 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 formed on the transparent plate 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 as described above, the plurality of transparent conductive films formed on one transparent plate are electrically connected in parallel. The electric resistance value as a whole can be lowered, and the electromagnetic wave shielding property can be improved.

Such a transparent conductive film may be formed on the exposed surface of the transparent plate, or in the mating type, on the mating surface side of the transparent plate, or in the multi-layer type and the multiple type. May be formed on the surface of the transparent plate on the inner hollow layer side. When the transparent conductive film is formed on the mating surface side or the inner hollow layer side surface as described above, the transparent conductive film can be prevented from being exposed to the outside, and the transparent conductive film can be protected. It is advantageous in the case of a transparent conductive film which is insufficient in terms of. Of course, combined type, multi-layer type,
In the case of multiple types of transparency, a transparent conductive film may be formed on the exposed side surface.

Further, the transparent conductive film may be formed on one surface of the transparent plate, but may be formed on two or more surfaces as necessary. The example shown in FIGS. 1, 2, and 6 is an example in which the transparent conductive film 5 is formed on one surface of the transparent plate 2, and the example shown in FIG. 7 constitutes one mating type transparent plate 2. This is an example in which transparent conductive films 5 and 6 are formed on both sides of one transparent plate.
FIGS. 8 and 9 show an example in which transparent conductive films 5 and 6 are formed on one surface of one transparent plate of a multi-layer type composed of two transparent plates or each transparent plate 2 and 4, respectively.

As the conductive grid pattern formed on the transparent plate of the present invention, a grid pattern made of a material having excellent conductivity is used so as to shield electromagnetic waves. This conductive grid pattern, for example, Ag, Al, Au, those formed by printing a conductive paste containing a metal powder such as Cu and a binder in a predetermined grid pattern, cured or baked, or Al foil. Or a foil formed by pasting a Ni foil on a predetermined lattice pattern, or a lattice pattern made of a conductive metal formed on the surface or by pasting or sandwiching a plastic film formed on the intermediate layer. Things are used. As the transparent plate on which the conductive grid pattern is formed, a mesh glass plate in which metal wires are encapsulated in a grid pattern or a mesh plastic plate can be used. Alternatively,
It is also possible to use a transparent plate obtained by inserting metal wires in a lattice pattern between two transparent plates and combining them. Alternatively, the grid body is made of metal or alloy of good electric conductor (for example, Al, Cu, stainless steel, brass, etc.) or other conductive material, or the grid body is made of plastic or the like, and the good electric conductor is formed on the surface of the grid body. Which is formed by forming a coating layer of the above metal or alloy or other conductive material, or a metal or alloy of a good electric conductor, or other conductive material to form a lattice, and a coating layer or an insulating layer on the surface thereof. The grid pattern may be formed by pasting, adhering, or fixing the applied product on a transparent plate.
The lattice pattern may be formed on one surface of the transparent plate, but may be provided on two or more surfaces or inside if necessary.

The front shape of the grid of each unit of the conductive grid pattern is not particularly limited, triangle, quadrangle, pentagon,
A polygonal pattern such as a hexagon or any other arbitrary pattern 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 in terms of transparency and light transmission.

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

In the example shown in FIGS. 2 and 4, a glass plate is used as a transparent plate, and a silver paste is print-printed on a grid pattern in which the shape of the unit grid is a square on the surface of the glass plate, and the conductive grid pattern is printed by baking. The square lattice has a diagonal length of 10 cm and the lattice pattern has a thickness of 20 μm.
By setting m and the line width to 1 mm, it is possible to effectively shield electromagnetic waves of 400 MHz or less.

The example shown in FIG. 3 uses a glass plate as a transparent plate,
Silver paste is printed and printed on a grid pattern in which the shape of the unit grid is rectangular on this glass plate surface, and baked to form a conductive grid pattern.The diagonal length of the rectangular grid is 20 cm. The film thickness of 20 μm makes it possible to effectively shield electromagnetic waves below 300 MHz.

The example shown in FIG. 5 uses a glass plate as a transparent plate,
A silver paste is printed and printed on a lattice pattern in which the shape of the unit lattice is a triangle on this glass plate surface, and a conductive lattice pattern is formed by baking.The height of the triangular lattice is 10 cm, and the lattice length is 10 cm. By making the pattern film thickness 20 μm and the line width 1 mm, it is possible to effectively shield electromagnetic waves of 400 MHz or less.

In the electromagnetic wave shielding transparent plate having the transparent conductive film and the conductive grid pattern of the present invention, the transparent conductive film and the grid pattern may be respectively formed on different surfaces of the transparent plate.

In the electromagnetic wave shielding transparent plate of the present invention, the transparent conductive film and the conductive lattice pattern may be in a conductive state when they are formed in an overlapping manner, but the transparent conductive film is an electromagnetic wave in a higher frequency range (for example, 100 The transparent conductive film and the conductive grid pattern are made non-conductive so that the electromagnetic wave in the low frequency region (for example, 400 MHz or less) can be effectively shielded. In this case, the transparent conductive film and the conductive grid pattern may be formed on different surfaces of the transparent plate to be in a non-conducting state, or the transparent conductive film and the grid of a good electrical conductor may be in a non-conducting state. In addition, an electrically insulating layer may be interposed between at least the portions in contact with each other.

In a particularly preferred embodiment, the transparent conductive film and the conductive grid pattern are separately provided on different surfaces of the transparent plate. By doing so, a high electromagnetic wave shielding performance in a wide frequency band can be obtained by the synergistic effect of the electromagnetic wave shielding performance of the transparent conductive film and the conductive lattice pattern.

Provide at least one of the transparent conductive film and the electrically conductive grid pattern with an earth connection end for earth so that the electromagnetic waves incident on these are dropped to the earth and electromagnetic wave shielding performance is exerted. You can The transparent conductive film and the grid pattern are separately provided with ground connection ends. In the case of transparent conductive film and / or lattice pattern, conductive paste containing conductive metal powder such as Ag or Al is usually printed and printed on a suitable peripheral portion on the surface of the transparent conductive film with a predetermined pattern, baked or cured. To form a busbar, or to form a predetermined pattern of Al
A foil or Cu foil is attached to form a bus bar, and an earth connection end is provided at an appropriate position on the bus bar. If desired, a terminal can be attached to this ground connection end to facilitate the connection of the ground wire. The ground connection end may be provided at one place or at a plurality of places.

It should be noted that the transparent conductive film and / or the grid pattern does not necessarily have to be provided with the ground connection end. For example, exposing a predetermined portion of the transparent conductive film and / or the lattice pattern,
When the transparent plate is attached to the sash or the like, a conductive sealant may be provided on the exposed portion of the transparent conductive film and / or the lattice pattern, and the conductive sealant may be used to establish electrical connection with the sash.

[Operation and Effect] According to the present invention, since the transparent conductive film and the conductive grid pattern are formed on the transparent plate, a high electromagnetic wave shielding effect is achieved by the functions of both the transparent conductive film and the conductive grid pattern. Is obtained. In particular, the transparent conductive film has a high shielding performance for high frequency electromagnetic waves of 300 MHz or higher, and the grid pattern, which is a good conductor, has a high shielding performance for low frequency electromagnetic waves of 400 MHz or lower. When used in combination, electromagnetic waves in the frequency range radiated from computers, word processors, measuring instruments, robots, and other electronic devices to which various digital technologies are applied to the surrounding environment, and malfunctions and adverse effects on these types of electronic devices and information networks, etc. Electromagnetic waves in the frequency range that gives, for example, 10MHz to 1000M
It is possible to effectively shield electromagnetic waves in a wide band above Hz.

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

[Brief description of drawings]

1 and 6 to 9 are cross-sectional views of the electromagnetic wave shielding transparent body according to the present invention, and FIGS. 2 to 5 are plan views of the electromagnetic wave shielding transparent plate according to the present invention. 1; Electromagnetic wave shielding transparent plate, 2, 3, 4; Transparent plate, 5, 6; Transparent conductive film, 7, 8, 9; Conductive grid pattern.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location E06B 9/24 A (72) Inventor Masatake Nakamura 2-16-1 304 Kinuta, Setagaya-ku, Tokyo ( 72) Inventor Toshiyuki Ishikawa 3-2-18 Ainokawa, Ichikawa City, Chiba Prefecture (56) References: 62-199999 (JP, U) JP 56-39038 (JP, B1)

Claims (5)

[Claims] 1. A transparent plate, wherein a transparent conductive film and a conductive grid pattern are formed on the transparent plate, and the transparent conductive film and the conductive grid pattern are formed on the transparent plate. An electromagnetic wave shielding transparent plate, which is provided in a non-conducting state without having a portion in contact with. 2. The electromagnetic wave shield according to claim 1, wherein a transparent conductive film is formed on one surface of the transparent plate, and a conductive grid pattern is formed on the opposite surface. Transparent plate. 3. A transparent conductive film and a conductive grid pattern are laminated on one surface of a transparent plate in an electrically non-conductive state with an electrically insulating layer interposed therebetween. The electromagnetic wave shielding transparent plate according to item 1. 4. A transparent conductive film is formed on both surfaces of the transparent plate, and a conductive grid pattern is formed in a non-conductive state on at least one surface of the transparent plate via an electrically insulating layer. An electromagnetic wave shielding transparent plate according to claim 1. 5. The electromagnetic wave shielding transparent plate according to claim 1, wherein the transparent plate is a glass plate.