JPH0660196U - Flexible sheet to prevent electrical and electromagnetic interference - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a flexible sheet that prevents the generation of static electricity, charging, and damage due to electromagnetic waves. [Structure] Two or three layers of (semi) conductive flexible sheet portion having a specific resistance value of less than 10 ⁸ Ω · cm, and 10 ¹⁰
One or two layers of insulating flexible sheet parts having a specific resistance value of Ω · cm or more are alternately laminated, and both surfaces of this laminate are formed by (semi) conductive flexible sheet parts, and (semi) conductive The flexible flexible sheet portion includes a matrix made of rubber or synthetic resin and a conductive substance dispersed therein, and the insulating flexible sheet portion is an electrically insulating fibrous base fabric and impregnated, coated or attached thereto. A flexible sheet for preventing electric and electromagnetic interference, which is attached and formed of an electrically insulating material made of insulating rubber or synthetic resin.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a flexible sheet for preventing electric and electromagnetic interference.

[0002]

[Prior art]

Conventionally, flexible sheets made of various synthetic resins or synthetic or natural rubber have been used as flexible covering materials for equipment covers and the like, and many of them are reinforced with fiber materials. However, these sheets were electrically insulating in nature and generally had a resistivity value of 10 ¹⁰ to 10 ¹⁷ Ω · cm or more, often 10 ¹² Ω · cm or more. Therefore, these conventional sheets have a strong tendency to generate static electricity due to surface friction and become charged.

As various electric devices have been developed and spread in recent years, the occurrence of static electricity and electromagnetic interference due to static electricity generation and electrification of the flexible sheet has increased, and a drastic solution to this problem is strongly required. It's coming.

In the case of such a flexible sheet, it may be possible to achieve the object by applying a conductive paint or the like on the surface of an ordinary non-conductive sheet. Adhesion to the surface of the sheet becomes a problem, and the flexible sheet is easily bent due to severe bending, and it is difficult to obtain a sheet having a sufficient practical service life. In addition, when applying a conductive paint, there are many limitations on the hue, and it is difficult to obtain a colorful sheet, and there are problems such as the coating technique and the performance of the coating film. It was difficult to form a conductive film.

In addition, even if only one side of the sheet is made conductive, if the opposite side is insulative, the opposite side is easily charged with static electricity. In terms of antistatic properties, it could not be used in applications where static electrification is extremely disliked.

[0006]

[Problems to be solved by the device]

 The present invention is intended to provide an electric and electromagnetic wave interference prevention flexible sheet that does not generate static electricity and electrostatic charge, does not generate electric and electromagnetic wave interference, and has mechanical strength sufficient for practical use. .

[0007]

[Means for Solving the Problems]

The flexible sheet for preventing electric and electromagnetic interference according to the present invention comprises two or three layers of conductive or semi-conductive flexible sheet portion having a specific resistance value of less than 10 ⁸ Ω · cm, and the two or three layers. , Which is inserted or laminated between the conductive or semi-conductive flexible sheet parts and has a one-layer or two-layer electrically insulating flexible sheet part having a specific resistance value of 10 ¹⁰ Ω · cm or more. A laminated body, wherein both front and back surfaces of the laminated body are formed by the conductive or semiconductive flexible sheet portion, and the conductive or semiconductive flexible sheet portion is an electrically insulating rubber and A matrix component comprising at least one selected from synthetic resins and a conductive substance contained in the matrix component, and the insulating flexible system. The electrically conductive portion is formed of an electrically insulating fibrous base cloth and an electrically insulating material that is impregnated, coated or adhered to the electrically insulating fibrous base cloth and is made of at least one selected from an electrically insulating rubber and a synthetic resin. It is characterized by

[0008]

[Action]

The flexible sheet for preventing electric and electromagnetic interference of the present invention (hereinafter referred to as the flexible sheet of the present invention) has one or two layers of an electrically insulating flexible sheet portion and two layers which are alternately laminated and adhered thereto. Or a three-layer conductive or semi-conductive flexible sheet portion, and the front and back surfaces of this laminate each have one layer of the above-mentioned conductive or semi-conductive flexible sheet portion. It is formed by. The specific resistance value of the insulating flexible sheet portion used in the present invention is 10 ¹⁰ Ω · cm or more, preferably 10 ¹⁰ to 10 ¹⁸ Ω · cm.

In addition, the conductive or semi-conductive flexible sheet portion used in the present invention has a specific resistance value of less than 10 ⁸ Ω · cm, and particularly has a specific resistance value of 10 ⁵ Ω · cm or less. The flexible sheet portion is preferable, and in this case, the specific resistance value thereof may be 10 ¹ Ω · cm or less, if necessary.

In the flexible sheet of the present invention, each of the insulating sheet and the conductive or semi-conductive sheet needs to be flexible. In the flexible sheet of the present invention, both front and back surfaces are formed by conductive or semi-conductive flexible sheet portions, and between the front and back conductive or semi-conductive flexible sheet portions, 1 It consists of a sheet-like base cloth consisting of two layers of insulating flexible sheet parts, or two layers of insulating flexible sheet parts, and one layer of conductive or semi-conductive flexible sheet parts inserted and laminated between them. Sheet-like base fabrics are sandwiched and laminated.

The conductive or semi-conductive flexible sheet portion used in the present invention is prepared by blending a conductive material in a matrix made of synthetic resin, synthetic rubber or natural rubber, and setting the specific resistance value of this blend to a predetermined value. It is adjusted and formed.

In the flexible sheet of the present invention, the electrically insulative flexible sheet portion is selected from electrically insulative fibrous base cloth, impregnated, coated or adhered thereto, and electrically insulative rubber and synthetic resin. It is made of at least one electrically insulating material.

As described above, an electrically insulating synthetic resin, synthetic rubber or natural rubber is used for the matrix of the conductive flexible sheet portion and the insulating flexible sheet portion which constitute the flexible sheet of the present invention. Examples of preferable synthetic resins include polyvinyl chloride (PVC), polyurethane, ethylene-vinyl acetate copolymer, isotactic polypropylene, polyethylene, polyacrylonitrile, polyester and polyamide, and other known materials. Examples of preferable synthetic rubber include styrene-butadiene rubber (SBR), chlorosulfonated polyethylene rubber, polyurethane rubber, butyl rubber and isoprene rubber, and other known materials. The most preferred synthetic resin is PVC, which may contain plasticizers, fillers, colorants, stabilizers, blowing agents and / or other modifiers. Further, these rubbers or synthetic resin materials may contain air bubbles or may be porous depending on the use and purpose.

The conductive material mixed in the matrix of the conductive or semi-conductive flexible sheet portion to control its specific resistance value to a predetermined value includes liquid, powder, fibrous and foil. -Shaped, linear or sheet-shaped conductive substances such as carbon black, metals such as Al, Au, Ag, Pt, Cu, Cr, Ni, Zn, Ti, Pb, Sn, Pd and their compounds or Ni -Cr alloys, or other conductive compounds such as indium oxide. The blending amount of the conductive substance is determined in consideration of the inherent conductivity, properties and desired degree of conductivity of the substance, but it is preferably at least 5% by weight, and 10 to 70% by weight. It is more preferable that there is. Of course, the compounding amount of the conductive substance is not limited to 70% by weight or less, and particularly in the case of the conductive flexible sheet portion, it has a desired flexible sheet property (strength, flexibility, appearance, etc.). As long as it is, it may be more than 70% by weight. For reference, the specific resistance values of various materials are shown below.

Material resistivity (Ω · cm) Natural asphalt 10 ¹⁵ to 10 ¹⁷ Vulcanized natural rubber 10 ¹⁵ to 10 ¹⁷ Butyl rubber 10 ¹⁵ to 10 ¹⁶ SBR 10 ¹² Polyisoprene 10 ¹⁵ Ethylene-propylene rubber 10 ¹⁵ to 10 ¹⁶ Neoprene 10 ¹⁰ to 10 ¹² Chlorosulfonated polyethylene rubber 10 ¹⁴ Urethane rubber 10 ¹⁴ to 10 ¹⁵ Polyethylene terephthalate 10 ¹⁹ Nylon 6 10 ¹² to 10 ¹⁵ Nylon 66 10 ¹³ to 10 ¹⁴ Polypropylene 10 ¹⁶ Polyvinyl chloride 10 ¹⁶ to 10 ¹⁷ Nomec paper 10 ¹⁶ cotton 10 ^{7 -10 12} carbon black, graphite 100 ^{0 -10 -3} stainless steel 10 ^{-4 -10 -6}

The thickness of each of the insulating flexible sheet portion and the conductive or semi-conductive flexible sheet portion is not particularly limited as long as the flexibility of the flexible sheet of the present invention is not impaired, but it is generally 1 μm or more. Is preferable, and it is more preferable that the thickness is 10 to 1,000 μm, but of course, it may be thicker than this.

As described above, the flexible sheet of the present invention made of the above-mentioned materials is a combination of the conductive or semi-conductive flexible sheet portion and the insulating flexible sheet portion. The structure of the invented flexible sheet will be described in more detail with reference to the attached drawings.

1 and 2 are cross-sectional views schematically showing an example of an electric and electromagnetic wave interference prevention flexible sheet according to the present invention in the accompanying drawings. The flexible sheet of the present invention shown in FIG. 1 comprises a sheet-like substrate composed of an insulating flexible sheet portion 1 and conductive or semi-conductive flexible sheet portions 2 formed on both surfaces thereof.

In the flexible sheet shown in FIG. 2, the insulating flexible sheet portion 1 having two layers and the conductive or semi-conductive flexible sheet portion 2a having one layer inserted and laminated between them are formed into a sheet shape. The base 1a is configured, and the conductive or semiconductive flexible sheet portion 2 is arranged on both front and back surfaces thereof, and these are integrated. The flexible sheet of the present invention having the configuration shown in FIG. 2 is able to improve the safety and reliability even when the usage environment conditions on the front and back surfaces are different, so that a particularly preferred embodiment. Is.

The insulative flexible sheet 1 shown in FIGS. 1 and 2 comprises an electrically insulative fibrous base cloth and an electrically insulative material made of an electrically insulative rubber and / or a synthetic resin. The insulating material may be impregnated into the fibrous base cloth, may be applied in the form of a film, or may be adhered in the form of a film.

In the production of the flexible sheet of the present invention, a conductive or semi-conductive flexible sheet (or film) may be laminated on both surfaces of the insulating flexible sheet portion and combined, or the insulating flexible sheet portion. A conductive or semi-conductive coating film forming liquid may be applied to both surfaces of the above and solidified.

In order to form an insulative flexible sheet portion by impregnating, coating or adhering an electrically insulative material on a fibrous base fabric, and also on the insulative flexible sheet portion, conductive or semi-conductive In order to form the flexible sheet part, calender method (sticking), topping method (sticking), dipping method (impregnation), coating method (coating), laminating method (sticking), extrusion molding method (sticking) ), Sprinkling method (application), and any other method can be used.

The insulative flexible sheet portion of the flexible sheet of the present invention includes an electrically insulative fibrous base cloth. Useful fibrous base fabrics include natural fibers such as cotton and hemp, inorganic fibers such as glass fibers, regenerated fibers such as viscose rayon and cupra, semi-synthetic fibers such as di- and At least one selected from triacetate fibers and the like, and synthetic fibers such as nylon 6, nylon 66, polyester (polyethylene terephthalate etc.) fibers, aromatic polyamide fibers, acrylic fibers, polyvinyl chloride fibers and polyolefin fibers. There are things that consist of. The fibers in the base cloth may be any shape such as short fiber spun yarn, long fiber yarn, split yarn, tape yarn, etc., and the base fabric may be woven fabric, knitted fabric, non-woven fabric, paper-like product or these It may be any of composite fabrics. Generally, it is preferable to use polyester fibers as the fibers constituting the insulating fibrous base fabric, and the fibers are preferably in the form of long fibers (filaments). The fibrous base fabric is useful for maintaining the mechanical strength of the obtained flexible sheet of the present invention at a high level. Examples of useful woven fabrics include twill woven fabrics, plain woven fabrics and other woven fabrics having a general design.

In the flexible sheet of the present invention, as shown in FIG. 1, two outer surfaces are formed by a conductive or semi-conductive flexible sheet portion 2, and the sheet-like substrate inside thereof is formed by the insulating flexible sheet portion 1 only. It can also be formed by. In this case, the flexible sheet has a structure that conforms to the required performance of the upper surface and the lower surface when in use, and does not cause problems such as clinging during handling.

In addition, as shown in FIG. 2, from the two-layer insulating flexible sheet portion 1 and the one-layer conductive or semi-conductive flexible sheet portion 2a sandwiched between them. In the case of the flexible sheet of the present invention, which is composed of the sheet-like substrate 1a configured and the conductive or semi-conductive flexible sheet part layer covering both front and back surfaces, the conductive flexible sheet on the outermost surface on both front and back sides is used. Each of the parts 2 has an antistatic function and an electromagnetic wave shielding function, the insulating flexible sheet part 1 underneath prevents leakage, and the conductive flexible sheet part 2a (center layer) underneath blocks the electromagnetic wave. And the insulating flexible sheet portion 1 thereunder further improves the electrical insulation of the flexible sheet of the present invention. Therefore, the electrical conditions applied to (or generated by) one of the conductive or semi-conductive flexible sheet parts on the outermost surfaces of the front and back do not interlock with the other, and electrostatic charge prevention and electromagnetic wave The effect of obstacle prevention can be improved. Therefore, the flexible sheet of the present invention having this configuration may be used by making the electrical conditions on the front and back sides different from each other. For example, even when the flexible sheet of the present invention is used as a work sheet, it is possible to prevent electrical changes or troubles on the outer surface from affecting electric equipment or human bodies in contact with the inner surface side.

[0026]

【Example】

The present invention will be described below with reference to examples. Example 1 In Example 1, a plain weave fabric was prepared by weaving 250 denier polyester filaments in the warp and weft yarns at a density of 45 filaments / 25.4 mm, respectively. Resin, 60 parts by weight of dioctyl phthalate, and a predetermined amount of stabilizer are dipped and impregnated in an insulating working liquid, squeezed to a pick-up rate of 100% of the working liquid, dried, and gelled at 180 ° C to heat the resin. Fixed. This formed a reinforced insulating flexible sheet. The insulating flexible sheet had a thickness of about 0.25 mm. The specific resistance value of the insulating flexible sheet was 10 ¹⁶ Ω · cm.

Next, a conductive processing liquid containing 100 parts by weight of polyvinyl chloride resin and 250 parts by weight of carbon black is applied to both surfaces of the above-mentioned insulating flexible sheet, dried, and subjected to gelation heat treatment at 180 ° C. Then, a conductive flexible sheet portion having a thickness of 0.1 mm on each of the front and back sides and a specific resistance of 10 ⁴ to 10 ⁶ Ω · cm was formed. The total thickness of the obtained flexible sheet of the present invention was about 0.5 mm.

When a simple box was made in the laboratory using the flexible sheet of the present invention, and sewing work was performed using a high-frequency sewing machine in the box, no noise was generated on the television screen that was lit just outside. It was For comparison, a similar test was performed using a conventional PVC sheet, and the same test was performed using a conventional PVC sheet that had only an antistatic treatment that caused the TV screen to be disturbed. The screen is disturbed.

In addition, the flexible sheet of the present invention does not generate static electricity and is not charged on either of the front and back surfaces of the flexible sheet. For example, it was possible to block troubles such as electric discharge and electric leakage, and as a whole, it was possible to use it safely and effectively without troubles such as electrification, electric discharge and electric leakage.

Example 2 The same operation and test as in Example 1 were carried out except for the following matters. An insulating flexible sheet was coated on both sides of the polyester filament plain weave fabric described in Example 1 with 100 parts by weight of polyvinyl chloride resin, 60 parts by weight of dioctyl phthalate, and a stabilizer having a thickness of 0.2 mm of transparent. This film was prepared by heating and pasting with a calendar method. The specific resistance value of this insulating flexible sheet was 10 ¹⁶ Ω · cm. The obtained flexible sheet of the present invention showed the same electric and electromagnetic wave interference preventing effects as in Example 1. Further, the conductive flexible sheet portion contains 100 parts by weight of polyvinyl chloride resin and 10 parts by weight of tin oxide, and has a thickness of 0.1 mm and a solid resistance value of 10 ⁴ to 10 ⁶ Ω · cm. The transparent conductive flexible sheet was formed by heating and pasting on both sides of the insulating flexible sheet by a calendar method. The flexible sheet of the present invention produced in this way also showed the same electric and electromagnetic wave interference preventing effects as in Example 1.

[0031]

[Effects of the Invention] The flexible sheet for preventing electric and electromagnetic interference of the present invention prevents electrostatic charging on both front and back surfaces, does not cause electromagnetic interference, has no risk of leakage to the back side, and has a surface friction. Even if it is used for, it has an extremely epoch-making composite effect that can maintain the above electrical characteristics with good durability. Therefore, the flexible sheet of the present invention has an amazing advantage that it is suitable for versatile use by itself, which is of great industrial value. Furthermore, since the flexible sheet of the present invention has a high flexibility, it can be applied to any article in accordance with its shape, and can be sewn into any shape for use. Therefore, it is possible to easily supply an extremely wide variety of products.

[Brief description of drawings]

FIG. 1 is an explanatory cross-sectional view of an example of a flexible sheet of the present invention.

FIG. 2 is a cross sectional view showing another example of the flexible sheet of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating flexible sheet portion 1a ... Sheet-shaped substrate 2, 2a ... Conductive or semi-conductive flexible sheet portion

Claims (8)

[Scope of utility model registration request] 1. A two-layer or three-layer conductive or semi-conductive flexible sheet portion having a specific resistance value of less than 10 ⁸ Ω · cm and the two-layer or three-layer conductive or semi-conductive. 1 layer or 2 which is inserted / laminated between layers of the flexible sheet and has a specific resistance value of 10 ¹⁰ Ω · cm or more
A laminate having an electrically insulating flexible sheet portion of a layer, wherein the front and back surfaces of the laminate each have one layer of the conductive material,
Or a semiconductive flexible sheet portion, wherein the conductive or semiconductive flexible sheet portion is a matrix component composed of at least one selected from an electrically insulating rubber and a synthetic resin, and a matrix component in the matrix component. And a conductive material contained therein, and the insulating flexible sheet portion is an electrically insulating fibrous base cloth, impregnated, coated or affixed thereto, and made of an electrically insulating rubber and a synthetic resin. A flexible sheet for preventing electrical and electromagnetic interference, which is formed of an electrically insulating material of at least one selected from the above. 2. The flexible sheet for preventing electric and electromagnetic interference according to claim 1, wherein the conductive flexible sheet portion has a specific resistance value of 10 ⁵ Ω · cm or less. 3. The flexible sheet for preventing electric and electromagnetic interference according to claim 1, wherein the insulating flexible sheet portion has a specific resistance value of 10 ¹⁰ to 10 ¹⁸ Ω · cm. 4. The electric and electromagnetic interference prevention flexible according to claim 1, wherein the insulating rubber is selected from natural rubber, styrene butadiene rubber (SBR), chlorosulfonated polyethylene rubber, polyurethane rubber, butyl rubber, and isoprene rubber. Sheet. 5. The electric and electrical products according to claim 1, wherein the insulating synthetic resin is selected from polyvinyl chloride (PVC), polyurethane, ethylene-vinyl acetate copolymer, polypropylene, polyethylene, polyacrylonitrile, polyester, and polyamide. Electromagnetic interference prevention flexible sheet. 6. The flexible sheet for preventing electrical and electromagnetic interference according to claim 1, wherein the content of the conductive material is at least 5% by weight based on the conductive or semiconductive flexible sheet portion. 7. The flexible sheet for preventing electric and electromagnetic interference according to claim 6, wherein the content of the conductive material is 10 to 70% by weight. 8. The conductive material is carbon black,
The flexible sheet for preventing electric and electromagnetic interference according to claim 1, which is selected from a conductive metal, a conductive alloy and a conductive metal compound.