JPH07221485A - Electromagnetic wave shielding material for window, and its manufacture - Google Patents

Abstract

PURPOSE:To provide a transparent or semitransparent electromagnetic wave shielding material for a window, which is light and excellent in electromagnetic wave shielding capacity and is easy to line a glass board, and its manufacture. CONSTITUTION:Both sides of woven fabric 1 high in numerical aperture consisting of fibers plated with metal are covered with transparent or semitransparent soft vinyl chloride resin 2 reaching to both surfaces through apertures. Moreover, soft vinyl chloride resin is made to pierce the aperture of the woven fabric to cover both sides of the woven fabric with soft vinyl chloride resin by arranging the transparent or semitransparent soft vinyl chloride resin sheet on one side of the woven fabric high in numerical aperture consisting of fibers plated with metal, and heating and fusing the soft vinyl chloride resin under pressurization.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent or translucent electromagnetic wave shielding material for windows for achieving electromagnetic wave shielding in windows.

[0002]

2. Description of the Related Art In recent years, with the development of electronic devices, there has been a problem of electromagnetic interference caused by various electromagnetic noises and the magnitude of the influence of electromagnetic waves on the human body. Further, leakage of electromagnetic waves from various information devices and computers, that is, leakage of information, is becoming a serious problem. In order to prevent these electromagnetic interference and leakage, various measures have been taken conventionally.

For example, a casing of electronic equipment is coated with a conductive paint, aluminum is vapor-deposited on the casing, an electroless plated material is used, or metal fibers or copper powder is mixed. For example, plastic materials are used for the case. However, these are all opaque materials and are not suitable as an electromagnetic wave shielding material for windows which are required to be transparent or translucent.

Further, as a transparent electromagnetic wave shielding material, ITO is formed on the surface of glass or a transparent plastic film.
There is a thin film of (indium tin oxide) deposited by sputtering. Further, a laminated sheet in which a hard transparent plastic sheet is arranged on both sides of a metal net or a copper fiber-dyed acrylic fiber woven cloth and laminated in a sandwich using an adhesive is also used.

[0005]

However, since a thin film of ITO is sputter-deposited on the surface of glass or a transparent plastic film, the thin film has a low electromagnetic wave shielding performance and, in view of the manufacturing method, has a large size like a window. Those (for example, 1200 × 900 mm) are difficult to make inexpensively.

A laminated sheet in which a metal net or a woven acrylic fiber cloth dyed with copper ions is sandwiched between hard transparent plastic sheets is mainly used for a personal computer CR.
A small one is used such as placed in front of T to prevent influence on the human body. If this is made large, it is too heavy to be attached to the window glass. Also, it is not flexible, so it is difficult to attach it to the window glass.

It is also conceivable that one side of a hard transparent plastic sheet is covered with a metal net or an acrylic fiber woven cloth dyed with copper ions, but the woven cloth is evenly spread on the hard plastic sheet without any unevenness. Quite difficult. Further, when the metal net or the woven fiber cloth comes to the outside of the window or the inside of the room, the net or the woven cloth may be frayed by the impact of a bird or an object touching it. Also, dust collects easily, which reduces transparency and makes it easier to clean.
Sometimes the nets and woven fabrics are frayed and cleaning is not possible. Further, when the metal net or the woven fiber cloth is attached to the glass plate of the window, the metal net or the woven fiber cloth is difficult to stick to the glass surface, and even if it is stuck, it easily falls.

An object of the present invention is to provide a transparent or semitransparent electromagnetic wave shielding material for windows, which is lightweight, has excellent electromagnetic wave shielding performance, and can be easily attached to a glass plate, and a method for producing the same.

[0009]

DISCLOSURE OF THE INVENTION The present inventors have as an electromagnetic wave shielding material for windows 1) transparent or semi-transparent, 2) excellent in electromagnetic wave shielding effect (for example, 50 dB or more), 3 We made an earnest effort to create an electromagnetic shielding material that satisfies the requirements of 4) being flexible and easy to attach to window glass, 4) being able to manufacture large products of 1 square meter or more, and 5) being inexpensive. As a result, they have found that by coating a metal-plated woven fabric with a soft vinyl chloride resin, all the above-mentioned requirements can be satisfied, and the present invention has been completed. That is,

In the electromagnetic wave shielding material for a window according to the first aspect of the present invention, both sides of a woven fabric having a high porosity, which is composed of fibers whose surfaces are metal-plated, are transparent or semi-permeable and reach both sides through the perforations. It was constructed such that it was coated with a transparent soft vinyl chloride resin.

According to a second aspect of the present invention, in the electromagnetic wave shielding material for a window according to the first aspect, the fiber whose surface is plated with a metal is a nickel-plated polyester fiber or polyamide fiber. .

According to a third aspect of the present invention, in the electromagnetic wave shielding material for a window according to the first or second aspect, the woven fabric has a porosity of 30 to 80%, and the soft vinyl chloride resin has a light transmittance. It was configured to be 30% or more.

In the method for producing an electromagnetic wave shielding material for windows according to the present invention, a transparent or translucent soft vinyl chloride resin is provided on one surface of a woven fabric having a high porosity, the surface of which is made of metal-plated fibers. A sheet is placed, and the soft vinyl chloride resin is heated and melted under pressure so that the soft vinyl chloride resin penetrates through the openings of the woven cloth and covers both sides of the woven cloth with the soft vinyl chloride resin. did.

A woven fabric made of fibers having a surface plated with a metal (hereinafter referred to as a metal-plated woven fabric) is a flexible fiber plated with a metal (nickel, copper, etc.), for example, a synthetic fiber such as polyester or polyamide. However, other fibers (including natural fibers) may be used or used in combination. Plain weave, taffeta, or the like can be used as the form of the woven fabric.

To be transparent or translucent, a woven fabric is used that is roughly woven so that the other side can be seen through.
The porosity is preferably 30 to 80% from the viewpoint of transparency, strength of the woven fabric and electromagnetic wave shielding property, and 30 to 50.
% Is semitransparent, and 50% or more is almost transparent.
The porosity here means the ratio of the open area of the woven cloth to the whole when the plane of the mesh structure is viewed vertically.

There is no limitation on the thickness of the woven cloth, but since the thickness affects transparency and flexibility, a thickness of 50 to 250 μm is preferable.

Such metal-plated woven fabrics are already available on the market, for example PMO from DEVEX in Switzerland.
100, 200, 300, 400, 500, PMX22
5,250, etc. can be used.

As the soft vinyl chloride resin, a transparent or translucent colored or uncolored one containing a so-called softening agent or plasticizer in pure soft vinyl chloride resin is used. The flexibility of the resin, that is, the hardness of the resin changes depending on the addition amount of the softening agent or the plasticizer, and the soft vinyl chloride resin used in the present invention is, for example, JIS specified in JIS K6301.
The hardness A is preferably 30 or more and less than 80, and more preferably 30 or more and less than 50 and having a flexible property.

The light transmittance of the soft vinyl chloride resin is preferably 30% or more because it needs to be transparent or translucent.

The soft vinyl chloride resin is previously formed into a sheet by a technique such as calender molding. The soft vinyl chloride resin sheet is preferably smooth and flexible, and can be wet with water and stick tightly to the window glass. Therefore, the thickness is preferably 0.1 to 1.0 mm, more preferably 0.2 to 0.5 mm. The width and length are appropriately set according to the size of the product.

To cover the metal-plated woven fabric with the soft vinyl chloride resin, for example, pressure bonding by heating is performed. A continuous laminator is used for hot pressing, but a compression molding machine can be used when continuous pressing is difficult due to the difference in heat shrinkage between the soft vinyl chloride resin sheet and the metal-plated woven cloth.

In the case of a continuous type laminator, conditions such as roller temperature, pressure and running speed, and in the case of a compression molding machine, such as temperature, pressure and pressurizing time are important. These conditions depend on the properties of the soft vinyl chloride resin used. Differently, it is necessary to select the conditions suitable for each resin. The temperature is experimentally determined to be an appropriate temperature range for obtaining a desired structure while avoiding thermal decomposition of the resin.
° C., more preferably 150-170 ° C., the pressure in the case of compression molding machine 10 to 50 kg / cm ^2, more preferably 20
-40 Kg / cm ² is preferable. If the pressure is too high, the resin adheres to the rollers and the like and does not run smoothly, and the desired structure cannot be obtained. Also, if the pressure is too low, the desired structure cannot be obtained.

[0023]

[Example 1] P manufactured by DEVEX as a metal-plated woven fabric
MX225 was used. This woven fabric is a polyester fiber woven fabric with nickel plating and has a thickness of 140μ.
m, porosity 55%, DC resistance 80 to 110 mΩ / squ
are, shielding level 66 dB (400 MH
z).

As shown in FIG. 1, the metal-plated woven fabric 1 is made into 30
It was cut into a rectangle of 0 × 300 mm, and a soft vinyl chloride resin sheet 2a (plasticizer 30%, JIS hardness A40,
Thickness 0.3 mm, light transmittance 90%) 280 x 280
As shown in FIG. 2, the metal-cut woven fabric cut into squares of 10 mm is placed on one side of the metal-plated woven fabric so that the blanks 3 are left on each side by 10 mm.

This is inserted into a compression molding machine and the pressure is set to 30K.
g / cm ² , gradually heat up to 160 ° C in about 15 minutes
When the temperature was raised to, the mixture was gradually cooled, and after about 30 minutes, the temperature was returned to room temperature to release the pressure. When this was taken out from the compression molding machine, as shown in FIGS. 1 and 3 to 5, the soft vinyl chloride resin 2 passed through the openings 4 of the metal-plated woven fabric 1 and spreads around both sides 5, 6 of the metal-plated woven fabric. A sheet of metal-plated woven cloth uniformly coated on both sides with soft vinyl chloride resin,
That is, the electromagnetic wave shielding material 7 for windows of the present invention was obtained. In FIG. 4, 8 is a warp thread of the metal-plated woven fabric 1, 9 is a weft thread, 10 is a fiber constituting the thread, and 11 is a nickel plating layer.

This electromagnetic wave shielding material for windows is a direct reading haze computer HGM-2D type (C manufactured by Suga Test Instruments Co., Ltd.
It was 60% when the total light transmittance was measured with a light source.

To use this electromagnetic wave shielding material for windows, it is adhered to the window glass with an adhesive, and the metal-plated woven fabric exposed in the periphery is brought into contact with the window frame made of metal to be grounded. As a result, electromagnetic waves that try to pass through the window glass are blocked by the metal-plated woven cloth. The window electromagnetic wave shielding material may be attached to the glass plate at the stage of manufacturing the window glass.

[0028]

[Example 2] A large-sized electromagnetic wave shielding material for windows was prepared in the same manner as in Example 1 except that the size of the metal-plated woven fabric and the soft vinyl chloride resin sheet was used, using a compression molding machine for 900 x 900 mm flat plates. Got

[0029]

[Embodiment 3] As shown in FIG. 6, a long width 1.3 m and a length 2
A 0 m metal-plated woven fabric 12 (the same as in Example 1) was installed in a continuous heating laminator, and a soft vinyl chloride resin sheet 13 having a width of 1 m and a length of 20 m (the same as in Example 1).
Was placed on the metal-plated woven fabric so as to form a blank 12a of 15 cm on each side and heated and pressure-bonded by a heating roll. 170 sheets by preheating and roll heating
Both sides of the metal-plated woven cloth were uniformly coated with soft vinyl chloride resin by heating to ℃ and rolled to obtain a long-sized electromagnetic wave shielding material for windows.

At this time, the width is 30 cm in advance as shown in FIG.
When the heat-resistant tape 14 of No. 1 is pasted on the metal-plated woven cloth 12 at intervals of 2 m, the soft vinyl chloride resin 13 is not covered in that portion, and the tape 14 is cut later at a width of 1.3 mm, It is possible to obtain ten large-sized electromagnetic shielded materials for windows, each of which is conductive on four sides and has a central portion covered with a soft vinyl chloride resin.

[0031]

The electromagnetic wave shielding material for windows according to the first aspect of the present invention has excellent electromagnetic wave shielding performance, is thin and flexible, and is easily attached to the window glass, and its surface is coated with a soft vinyl chloride resin. Therefore, it has good compatibility with adhesives. Further, since the surface is protected by the soft vinyl chloride resin, the woven cloth inside is not easily damaged. Furthermore, since the soft vinyl chloride resin reaches both sides through the openings, it does not peel off.

According to the second aspect of the present invention, since it is a polyester fiber or a polyamide fiber, a woven fabric that is tough, flexible and has a high porosity can be obtained. Also, nickel plating is excellent in conductivity and therefore has an excellent electromagnetic wave shielding performance. An excellent and flexible electromagnetic wave shielding material for windows can be obtained.

According to the third aspect of the invention, the woven fabric has a porosity of 30 to 80% and the soft vinyl chloride resin has a light transmittance of 30.
%, It is possible to obtain a highly transparent electromagnetic wave shielding material for windows.

In the invention according to claim 4, the soft vinyl chloride resin sheet is placed on one surface of the woven fabric and heated under pressure, whereby the soft vinyl chloride resin is melted and penetrates through the openings of the woven fabric. Since it reaches the opposite side of the woven cloth and covers both sides of the woven cloth, it is extremely easy to manufacture, and the soft vinyl chloride resin is coated to a uniform thickness. No bubbles will get into the vinyl chloride resin.

[Brief description of drawings]

FIG. 1 is a plan view showing an example of an electromagnetic wave shielding material for a window of the present invention.

FIG. 2 is a diagram showing a stage in the middle of manufacturing an electromagnetic wave shield material for windows.

FIG. 3 is a front view of an electromagnetic wave shielding material for a window of the present invention.

FIG. 4 is a plan view of a part of the electromagnetic wave shielding material for windows.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is a diagram showing a process of manufacturing an elongated electromagnetic wave shielding material for windows.

[Explanation of symbols]

 1 Metal Plated Woven Fabric 2 Soft Vinyl Chloride Resin 2a Soft Vinyl Chloride Resin Sheet 3 Margin 4 Opening 5 Side 6 Side 7 Electromagnetic Wave Shielding Material for Window 8 Warp 9 Weft 10 Fiber 11 Nickel Plated Layer 12 Metal Plated Woven 12a Margin 13 Soft Vinyl chloride resin sheet 14 tape

Claims (4)

[Claims] 1. A woven fabric having a high porosity composed of metal-plated fibers on both surfaces, which is covered on both sides with a transparent or translucent soft vinyl chloride resin reaching both sides through the openings. Characteristic electromagnetic wave shielding material for windows. 2. The electromagnetic wave shielding material for windows according to claim 1, wherein the fiber whose surface is plated with metal is a nickel-plated polyester fiber or polyamide fiber. 3. The electromagnetic wave shield for windows according to claim 1, wherein the woven cloth has a porosity of 30 to 80% and the soft vinyl chloride resin has a light transmittance of 30% or more. Material. 4. A transparent or translucent soft vinyl chloride resin sheet is arranged on one side of a woven fabric having a high porosity, the surface of which is made of metal-plated fibers, and the soft vinyl chloride resin is heated under pressure. A method for producing an electromagnetic wave shield material for windows, characterized in that the soft vinyl chloride resin is melted to penetrate through the openings of the woven cloth and both sides of the woven cloth are covered with the soft vinyl chloride resin.