JPS635265B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention comprises an antistatic fibrous material and a conductive powder material, in which the fibrous material accounts for at least 5 to 50% by volume.
An antistatic material with a thickness of 0.02 mm to 1.0 mm made by mixing fibrous substances in an elastic polymer material whose main component is rubber, thermoplastic rubber, latex, liquid rubber, etc. and arranging them in a certain direction so that the Relating to an electromagnetic wave shielding rubber material formed by forming a sheet into a laminate of two or more layers, a butt of two or more pieces, or a combination thereof so that the fibrous substances are arranged in different directions. It is something. [Prior Art] In recent years, various electronic devices, communication receivers, computers, etc. have become widespread, and are now being used not only for business purposes but also for home use. However, many electronic devices generate interfering electromagnetic waves that interfere with the functioning of other devices. In order to prevent such disturbances, it is necessary to shield the generated interfering electromagnetic waves from being radiated in all directions, and also to shield the interfering electromagnetic waves entering from the outside. Conventionally, in order to solve these problems, for example, in the case of computers, metal plates were used for the exterior material or housing, or when polymer plastics were used, zinc spraying or conductive paint was applied. shields from interfering electromagnetic waves. As another method, a method has been developed in which electromagnetic waves are shielded by mixing a metal substance into the polymer plastic itself to make it conductive. Furthermore, penetrations or gaps in computer exterior materials where electromagnetic waves are likely to leak or enter, joints between cases of electronic components and switching regulators equipped with high-frequency power supplies, and waveguides. Joints and the like are coated with conductive paint, conductive caulking material or conductive adhesive, or soldered with metal solder. However, all of these methods require time and effort to process, and the electromagnetic wave shielding effect is still not sufficient. In addition, as another method to improve the above method, a method using conductive gaskets and gaskets, which requires less time and effort to process, has been developed. These methods attempt to obtain an electromagnetic wave shielding effect by mixing a large amount of conductive powder, particularly metal powder, into rubber or plastic to increase the conductivity of the material. However, on the other hand, these methods use a large amount of conductive powder, resulting in a product with a high specific gravity, high hardness, and poor elasticity, which is one of the drawbacks when used for packing and gaskets. In addition, when a large amount of metal powder is mixed, during transportation,
During installation, use, etc., metal powder may fall out of the matrix, making it difficult to obtain stable conductivity. In order to improve the drawbacks caused by the use of large amounts of conductive substances, research has been underway in recent years to use flat metal objects or metal fibers with a short diameter of 1 mm or more as substances to replace metal powder. The advantage of these is that since the metal substance is flat or fibrous, high conductivity can be obtained with a small amount compared to conductive powder. However, there are problems when using these substances, and an immediate solution is desired. That is, the flat or fibrous shape makes mixing and dispersion difficult, and there are problems with the adhesion with the matrix or the physical strength of the mixed molded product, and the cost is high. [Summary of the Invention] The present invention has been made to solve the above-mentioned conventional problems. diameter
Antistatic fibrous material with self-discharge ability, i.e., corona discharge ability, such as surface-treated thin metal wire of 0.2 mm or less in length from 0.1 to 20 mm, metal-plated fiber, metal-deposited fiber, conductive metal compound, adsorption fiber, carbon composite synthetic fiber, etc. substance 5
~50% by volume and less than 100% gold, silver,
10 to 40 parts by weight of a conductive powder material such as copper, aluminum, nickel, ferrite compound, graphite, conductive carbon black, etc. is mixed and dispersed, and the antistatic fibrous material is arranged in a certain direction.
An antistatic sheet of 0.02 to 1.0 mm is formed into a laminate of two or more layers, a butt of two or more pieces, or a combination thereof so that the antistatic fibrous materials are arranged in different directions. By this,
An object of the present invention is to provide an electromagnetic wave shielding rubber material that provides an excellent electromagnetic wave shielding effect. [Embodiments of the Invention] The present invention will be described below based on the drawings. The present invention is an electromagnetic wave shielding rubber material having the shapes as illustrated in FIGS. 1 to 11, but it goes without saying that it can be used in any desired shape according to the intended use, which is limited to those illustrated. . That is, FIG. 1 is a cutaway perspective view of an antistatic sheet 1 that constitutes a main part of the present invention. Here, the base material element of the antistatic sheet 1 is, for example, natural rubber and its latex, synthetic natural rubber and its latex, styrene-butadiene rubber and its latex, chloroprene rubber and its latex, acrylonitrile-butadiene rubber and its latex, Rubber elastic materials such as isobutylene-isoprene rubber, ethylene-propylene rubber, chlorosulfonated polyethylene rubber, fluorinated rubber, silicone rubber, polysulfide rubber, liquid silicone rubber, liquid urethane rubber, liquid butadiene rubber, liquid isoprene rubber, liquid chloroprene Rubber, liquid rubber elastic bodies such as liquid polysulfide rubber, styrene-isoprene terminal block copolymer, styrene-butadiene terminal block copolymer, EPDM polyolefin blend, ionomer, trans 1.4 polyisoprene,
1.2 Thermoplastic rubber that exhibits rubber elasticity at room temperature, such as polybutadiene, chlorinated polyethylene, epichlorohydrin rubber, thermoplastic urethane elastomer, ethylene-vinyl acetate copolymer, polyethylene-butyl rubber graft polymer, and elastic PVC. The main component is more than one type of polymer. Next, the antistatic sheet 1 contains gold, silver, copper, nickel,
Metal-deposited fibers, metal-plated fibers, conductive materials in which conductive metals such as aluminum or their compounds are vapor-deposited, plated, impregnated, or adsorbed on fibers such as cotton, cotton, rayon, acrylic, nylon, vinylon, polyester, polyethylene, polypropylene, etc. Thickness of 500 denier or less and length of 0.1 mm or more made by cutting fibers impregnated or adsorbed with a conductive metal compound, or carbon composite synthetic fibers mixed with conductive carbon into small pieces.
Antistatic fibrous material consisting of a carbon composite synthetic fibrous material with a corona discharge capacity of 20 mm, or a fine metal wire with a diameter of 0.2 mm or less and a length of 0.1 mm to 20 mm that has been surface-treated by pickling treatment, etc.2, 5- Metal powder such as gold, silver, copper, nickel, aluminum, ferrite compound, etc. with a volume resistivity of 50% by volume and 10 ⁸ Ω・cm or less, or conductive material such as graphite, conductive carbon, etc. of 100 mesh or less. 10 to 40 parts by weight of powder 3, preferably blended in advance, are added, dispersed almost uniformly, calendered,
The antistatic fibrous material 2 is formed into a sheet having a thickness of 0.02 mm to 1.0 mm and arranged in a certain direction by casting, dipping, and coating film. The antistatic fibrous material 2 has a thickness of 500 deniers or less and a length of 0.1 to 20 mm (for fine metal wires, a diameter of 0.2 mm or less and a length of 0.1 to 20 mm).
Since it is a short fibrous surface-treated fiber (mm), it is easy to disperse in rubber, has excellent adhesion to rubber, and is effective as a fibrous reinforcing agent, as well as improving the texture of the polymer. There's nothing to lose. Furthermore, when adding the above-mentioned antistatic fibrous material 2 and conductive powder 3, flame retardants such as antimony-based flame retardants represented by diantimony trioxide, phosphoric acid esters and phosphorus compounds, chlorine-based flame retardants, The antistatic sheet 1 can also be made flame retardant by adding a brominated flame retardant or the like so that the total amount is 15 PHR or more (15 parts by weight per 100 parts by weight of the polymer). The necessity of adding 15 PHR or more is because 15 PHR or more is required as the total number of flame retardant additions to impart self-extinguishing properties. Further, the antistatic sheet 1 in the form of a sponge sheet can be prepared by adding the above-mentioned additives together with a necessary foaming agent. Furthermore, especially from the aspect of reinforcing effect, a compound containing the above-mentioned additives can be applied to gray fabrics such as cotton, nylon, vinylon, polyester, stapler, rayon, polyethylene, polypropylene, acrylic, etc. by pressing, date coating, coating, friction, etc. The base fabric-containing antistatic sheet 1 can also be obtained by coating by a method such as topping. In addition, the gray fabric includes a part or all of the above-mentioned fibers plated, vapor-deposited, adsorbed or impregnated with conductive metals or metal compounds thereof, or carbon composite synthetic fibers mixed with conductive carbon. It can also be used to further enhance the conductivity and electromagnetic wave shielding effect. In addition, the thickness of the antistatic sheet 1 in the present invention is
A range of 0.02mm to 1.0mm is most effective. In other words, when the sheet has a wall thickness of 1 mm or more, the antistatic fibrous material 2 is not uniformly dispersed on the surface and inside of the sheet, and there is less on the surface and more on the inside, so the arrangement of the fibrous material 2 is not uniform. I'm disgusted. For this reason, 1
In the case of a sheet having a wall thickness of mm or more, the amount of fibrous material 2 must be added in an amount larger than necessary, which is not only uneconomical, but also the sheet 1 itself is thick.
There is a drawback that the thickness of the shielding rubber material (molded product) obtained by laminating and/or butting is limited to a large thickness. Further, if the thickness of the sheet 1 is 0.02 mm or less, there will be disadvantages such as difficulty in forming the sheet into a sheet, weakening of strength and easy tearing, and failure to expect long-term effects regarding wear. On the other hand, when the thickness of the sheet 1 is between 0.02 mm and 1.0 mm, the non-uniform dispersion of the antistatic fibrous material 2 within the sheet layer, which occurs due to the thinness of the sheet 1, is eliminated, and at the same time, the arrangement state of the fibrous material 2 is also reduced. Since it is extremely good, the addition of unnecessary antistatic fibrous material 2 can be avoided, and an antistatic sheet 1 that is inexpensive and stable in physical properties can be obtained. In this case, the thickness of the fibrous substance 2 mixed in is 500 denier or less or the diameter
The length is preferably 0.2 mm or less, and the length is preferably in the range of 0.1 mm to 20 mm. Thickness of 500 denier or more or 0.2 mm in diameter
This is because dispersion in the rubber compound is poor, alignment is difficult, and strength cannot be expected. Regarding the length, if the length is less than 0.1 mm, the fibrous material 2 can be dispersed well in the rubber, but the orientation effect of the fibrous material 2 is poor, and if it is 20 mm or more, the fibrous material 2 cannot be dispersed in the rubber, and the fibrous material 2 is not easily dispersed in the compound. There is a risk that they will get stuck together and not be arranged at all. On the other hand, the amount of antistatic fibrous material 2 is 5 to 50% of the total volume.
A range of percentages is appropriate. If it is less than 5%, the volume resistivity of the molded product increases, resulting in poor conductivity and no electromagnetic wave shielding effect. Also
If it exceeds 50%, it will be difficult to mix and disperse into the rubber, and the hardness of the resulting molded product will be too high, making it difficult to maintain strength and rubber elasticity. In particular, the amount of the antistatic fibrous material 2 is preferably in the range of 5 to 30 percent by volume, especially for low hardness and high elastic product applications. Furthermore, in the present invention, the conductive powder 3 of 100 meshes or less of particles such as gold, silver, copper, nickel, aluminum, ferrite compound, graphite, conductive carbon black, etc. is preferably applied in advance to an antistatic fibrous material. The purpose of this method is to secondarily help the probability of contact between the fibrous substances 2 and increase the conductivity. The volume ratio of the fibrous material 2 may be 50% or less, and as mentioned above, if 50% or more is mixed, the mixing and dispersion that occurs is poor, and the hardness of the resulting molded product is too high, making it impossible to obtain good elasticity. can be prevented.
On the other hand, since the conductive powder 3 is also used for the purpose of increasing the probability of contact between the fibrous materials 2, there is no need to use a large amount, but rather 10 to 40 parts by weight of the elastic polymer material. A small amount of range is desirable. In addition, if the fibrous material 2 and the conductive powder 3 are blended in advance and used, the fibrous material 2 will be coated with the conductive powder 3, which will prevent the fibrous material 2 from forming hair clumps. . As a result, the dispersion is extremely good and the arrangement of the fibrous material 2 is good, so it is possible to obtain good conductivity even with the addition of a small amount of both materials, and the molding has a relatively light specific gravity without impairing the rubber elasticity. You can get the goods. Note that blending the fibrous material 2 and the conductive powder 3 can be done relatively easily using a normal blender machine, but it is necessary to blend the fibrous material 2 and the powder 3 until they are sufficiently mixed. Good dispersion is obtained when blended with a softening agent such as some oil or plasticizer. Each of the antistatic sheets 1 thus obtained is laminated and/or butt-molded into a desired shape and thickness so that the antistatic fibrous substances 2 contained therein are arranged in different directions. Ru. In order to enhance the electromagnetic wave shielding effect, the arrangement of the antistatic fibrous material 2 contained in the molded product is important. That is, by arranging the fibrous substances 2, the volume resistivity in the arrangement direction decreases,
Improves conductivity. Therefore, when the fibers 2 are arranged in the direction in which electromagnetic waves enter, the shielding effect is greatest. Further, according to experiments, it has been found that if there is no or a small number of fibers 2 arranged, a sufficient shielding effect cannot be obtained unless the thickness of the molded product is at least 1 mm or more in the direction of propagation of electromagnetic waves. Therefore, if the fibers of a molded product are arranged in only one direction, electromagnetic waves in the same direction as the fiber arrangement can be shielded regardless of the thickness of the molded product, but against electromagnetic waves entering from multiple directions, the thickness must be kept at 4 mm or more. In other words, the most appropriate method for shielding electromagnetic waves is to use a molded product in which the fibrous materials 2 are arranged in the same direction with respect to the direction of ingress of electromagnetic waves. Therefore, if the direction of the incoming electromagnetic waves is always constant, the antistatic fibrous material 2 may be arranged in one direction. However, normally the electromagnetic waves do not always enter in the same direction. Taking these points into consideration, the present invention, as shown in FIG. By laminating and/or butt-molding the material 2 so that it is arranged in two or more directions, it is possible to effectively shield electromagnetic waves without worrying about the directionality of the incoming electromagnetic waves. For example, Figure 2 shows 2 pieces cut to the desired size.
This is an example of the electromagnetic wave shielding rubber material of the present invention, in which two antistatic sheets 1 are laminated so that the fibrous substances 2 contained in each sheet are arranged substantially perpendicular to the other sheet. Here, the effect of the multidirectional arrangement of the molded product is not only the electromagnetic wave absorption effect due to the same directionality of the fibrous material 2 as described above with the electromagnetic waves entering in two directions, but also the effect of quickly catching and absorbing the internally reflected entering electromagnetic waves in other layers. This has the effect of attenuating electromagnetic wave energy due to repeated internal reflections. Figure 3 shows an electromagnetic wave of the present invention in which the antistatic sheet 1 obtained as described above is laminated in three layers so that the antistatic fibrous material 2 contained therein is arranged in different directions in the same manner as in Figure 2. This is another example of the shielding rubber material. That is, in the case of FIG. 3, the arrangement direction of each of the fibrous substances 2 included in the first layer, second layer, and third layer is X.
The angles are 0°, 90°, and 45° to the axis, respectively. These 3
The effect of the electromagnetic wave shielding rubber material having the antistatic fibrous material 2 arranged in the direction is that if the ingress of electromagnetic waves is
When viewed from the axis, the electromagnetic waves undergo complicated reflections by the fibrous materials 2 because the fibers are arranged at different angles in the third layer, second layer, and first layer.
Through repeated internal reflections and absorption, electromagnetic wave energy decreases. In addition, when electromagnetic waves enter in the Z-axis direction, the A plane,
When surface A' is clamped by a metal clamp, part of the energy of the incoming electromagnetic waves is absorbed by the shielding rubber material and converted into thermal energy, which is immediately discharged from the first layer through the metal clamp. Furthermore, even if the surface of the shielding rubber material is charged with electrostatic energy due to the concentrated electromagnetic energy, it will be discharged through the metal clamp. Further, when the B side and the B' side are held together by a metal holding member, heat is quickly radiated and discharged from the second layer. FIG. 4 is an example of the molded product obtained in FIG. 2 being punched out. In this case, in order to prevent the separation of the fibrous material 2 exposed on the front and back surfaces and cut surfaces during vulcanization and punching and to prevent fuzzing, spraying or dipping is performed using emulsion, latex rubber solution, liquid rubber, etc. Coating film 4 on part or all of the front and back surfaces and/or side surfaces of the molded product.
was formed. The effect of coating the front and back surfaces and/or the sides is to eliminate the causes of dust caused by the fluffing of the fibrous material 2 and dirt caused by separation, and also to improve the texture. Fig. 5 shows the antistatic sheet 1 of Fig. 1 being cut to a desired size in the length and width directions, and the resulting sheets are butted and pasted together, and then press molded. This is another example of the obtained planar body having fibers arranged in different directions. As mentioned repeatedly, the most appropriate method when using the fibrous material 2 as an effective means for shielding electromagnetic waves is to arrange the fibrous material 2 in the same direction with respect to the direction of ingress of electromagnetic waves. The method is to use molded products that are However, in their research, the inventors of the present application found that when the antistatic fibrous material 2 included in an area corresponding to about 1/4 of the total area of the molded product that receives electromagnetic waves is arranged in the same direction as the electromagnetic waves enter, , even if the fibrous materials 2 included in other areas are in different directions, when they coexist, the electromagnetic wave shielding effect is almost unchanged compared to when the fibrous materials 2 are all arranged in the same direction. I discovered a surprising fact. This consists of an antistatic fibrous material 2 in which incoming electromagnetic waves are arranged in different directions, and a conductive powder 3 mixed at the same time.
It is thought that this is because complex reflections are repeated and energy attenuation occurs, and heat is dissipated and discharged more quickly than the fibrous material 2 arranged in the same direction. Although Fig. 5 shows an example of a molded product made by bonding two sheets together, it is also possible to bond three sheets together,
It is also possible to obtain a laminated molded product having fibers arranged in multiple directions by bonding four sheets together. Furthermore, it is of course possible to similarly provide a surface coating layer as shown in FIG. FIGS. 6 and 7 show other examples of molded products pressed into cylindrical bodies. Note that the cylindrical molded product can be cut into rings and used in the desired size. Of course, it is also possible to mold it into other desired shapes. Furthermore, regarding the manufacturing method of the cylindrical product, it is possible to vulcanize the fibrous material 2 by partially overlapping it so that it faces in different directions as shown in Fig. 6, or by vulcanizing all of the fibrous material 2 as shown in Fig. 7. It may also be made by stacking and pressing. FIG. 8 shows an example of the present invention in which an adhesive layer 5 is provided on a part or the entire surface of a molded product. In other words, it is a molded product coated with or laminated with a normal adhesive, adhesive, sealant, or conductive adhesive, adhesive, or sealant, which facilitates the work of attaching it to other objects. . Note that 6 in the figure is a release paper. FIGS. 9 and 10 show an example of the use of the present electromagnetic shielding rubber material in cases 7 and 8 of electronic parts. Note that 9 is earth. FIG. 11 shows an application example in which the electromagnetic wave shielding rubber material shown in FIG. 5 is used in the power plug 10. Needless to say, this example has the purpose of preventing noise generated when a plug is inserted into a power source, and has a good effect. Regarding the laminating and/or butting method in the present invention, after cutting each sheet 1, only a part thereof may be laminated and/or butted, or all of the sheets may be laminated and/or butted. good. In the case of vulcanization molding, pre-vulcanized antistatic sheets may be bonded together with an adhesive, or may be bonded together while unvulcanized and then vulcanized. When an unvulcanized sheet is used, the sponge sheet is foamed at the same time as vulcanization, or a semi-vulcanized sponge sheet that has been foamed in advance is used. As described above, the present invention is an electromagnetic wave shielding rubber material that has both high self-discharge ability (corona discharge ability) and good conductive performance. That is, as a result of various experiments, the present inventors have found that by combining an antistatic sheet with self-discharge ability and a conductive sheet with a conductive effect into one composition, it is possible to In comparison, the laminated sheet of the present invention has several times the electromagnetic wave shielding effect, and furthermore, the self-discharge ability of the laminated sheet of the present invention is several times higher than that of thin metal wires, metal-plated fibrous materials, metal-deposited fibrous materials, and carbon composite synthetic fibrous materials. By directly adding conductive substances such as conductive carbon to the mixed and dispersed antistatic sheet, these self-discharge abilities (corona discharge abilities) can be improved.
The present invention was achieved by discovering that this can be synergistically enhanced. Example 1

[Table] Antistatic sheet (sheet thickness 0.5 mm) made by mixing the formulation according to Table 1 above using a mixing roll and arranging fibrous substances in the longitudinal direction using a calender.
I got it. The thickness of the antistatic fibrous material used
It was 50 denier and 3mm long. Next, as shown in Figure 3, the antistatic sheet thus obtained was heated and formed by overlapping press molding so that the fibrous material arrangement direction was 0°, 90°, and 45° with respect to the Z axis. As a result, the characteristic values were as shown in Table 2.

[Table] The shielding effect was as shown in Figure 12.
The electromagnetic wave shielding effect was measured as follows (frequency band 100 to 1000 KHz).The electromagnetic wave measurement was performed using a spectrum analyzer TR4172 (manufactured by Takeda Riken), and the shielding effect was calculated using the following formula. Shielding effect (shielding effect) = 20log Incident electric field strength / transmitted electric field strength Electric field strength (V/m) Unit (dB) As shown in the above results, the molded product according to the present invention has an extremely good electromagnetic wave shielding effect and good rubber elasticity. and physical properties. Experimental example 2

[Table] The formulations shown in Table 3 above were mixed using a mixing roll and then sheeted using a calendar to obtain an antistatic sheet (thickness 1.0 mm) as shown in Figure 1. Two of these sheets were laminated so that the fibers were oriented in the same direction, and then butt-molded as shown in FIG. 5 and press-vulcanized. (Press conditions: 130° C. x 30 minutes, 4.2 Kg/cm ² ) The antistatic fiber used had a thickness of 30 denier and a length of 3 mm. The molded product thus obtained was a thin rubber plate in which the antistatic fibrous material was arranged on a plane in approximately half each in the vertical and horizontal directions. The physical properties and electromagnetic wave shielding effect of this thin rubber plate were measured in the same manner as in Experimental Example 1, and the results were as shown in Table 4.

【table】

〔Effect of the invention〕

As described above, the electromagnetic wave shielding rubber material of the present invention is
Wave guides, flange gaskets,
It can be used in a wide range of applications, such as box sealers and gaskets for electronic equipment, and noise filters for power plugs and sockets, to prevent electromagnetic interference (EMI) and radio frequency interference (RFI). Furthermore, depending on the frequency characteristics, it can be fully utilized as a magnetic shielding material and a radio wave absorber. Furthermore, the present invention is characterized in that it exhibits a shielding effect against electromagnetic waves entering from multiple directions. Furthermore, since the antistatic fibrous material and the conductive powder are used in combination in the present invention, it is difficult to cause fiber clumps or poor dispersion, and the fibrous material is oriented smoothly, and the powder comes into contact with the fibers. While the amount of conductive material is small and has a good shielding effect, especially compared to conventional gaskets used for this type of application,
It is possible to obtain an innovative electromagnetic shielding rubber material that has a low specific gravity and high elasticity and is sufficiently effective as a normal gasket. Furthermore, the present invention allows the surface to be coated, and as a result, it is possible to obtain stable quality that is less difficult to remove than molded products of fibrous materials and does not generate dust or dirt. Furthermore, by providing an adhesive or an adhesive layer on the front and back surfaces, it also has the advantage that it can be easily attached to other objects. In addition to being used in wave guides, flange gaskets, plugs, electronic equipment boxes, etc., the present invention can be used in a variety of products to prevent electromagnetic waves, and in terms of manufacturing costs, special equipment and machinery are not required. It has many advantages such as being inexpensive because it is not necessary.

[Brief explanation of the drawing]

Fig. 1 is a cutaway perspective view of an antistatic sheet according to the present invention, Figs. 2 and 3 are partially cutaway perspective views of a laminated electromagnetic shielding rubber material of the present invention, and Fig. 4 is a partially cutaway perspective view of an antistatic sheet according to the present invention. A partially cutaway perspective view of the electromagnetic wave shielding rubber material of the present invention, FIG. 5 is a perspective view of the electromagnetic wave shielding rubber material of the present invention formed by butt molding in which fibrous substances are arranged in two directions in a plane, and FIG. 6 is a molded product. FIG. 7 is a partially cutaway perspective view of a partially laminated cylindrical electromagnetic shielding rubber material of the present invention obtained by molding, and FIG. FIG. 8 is a perspective view of the electromagnetic shielding rubber material of the present invention obtained by coating the thin plate-shaped molded product shown in FIG. FIG. 11 is a diagram showing an application example of the electromagnetic shielding rubber material of the invention used in a power plug, and FIG. 12 is a diagram showing the shielding effect. In the figure, 1 is an antistatic sheet, 2 is an antistatic fibrous material, 3 is a conductive powder, 4 is a coating film, and 5
is the adhesive layer.

Claims (1)

[Scope of Claims] 1. A surface-treated fine metal wire with a thickness of 500 denier or less or a diameter of 0.2 mm or less and a length of 0.1 to 20 mm in an elastic polymer material whose main component is rubber, thermoplastic rubber, liquid rubber, or latex. Metal-plated fiber, metal-deposited fiber, conductive metal compound adsorption fiber,
5 to 50 volume percent of an antistatic fibrous material having self-discharge ability, i.e., corona discharge ability, such as carbon composite synthetic fibers, and 10 to 40 percent by volume of a conductive powder material of not more than 100 meshes.
Parts by weight are mixed and dispersed, and the antistatic fibrous material is arranged in a certain direction and has a thickness of 0.02 mm to 1.0 mm.
mm antistatic sheet is formed into a laminate of two or more layers, a butt of two or more pieces, or a combination thereof so that the antistatic fibrous materials are arranged in different directions. An electromagnetic wave shielding rubber material featuring: 2. The electromagnetic wave shielding rubber material according to claim 1, wherein the antistatic sheet is a flame retardant antistatic sheet containing 15 PHR or more of a flame retardant. 3. The electromagnetic wave shielding rubber material according to claim 1, wherein the antistatic sheet is a sponge-like antistatic sheet. 4 Pressing the antistatic sheet composition onto a fabric made of natural or synthetic fibers (gray fabric), preferably a fabric in which an antistatic fibrous substance is used as a part of the fabric.
The electromagnetic wave shielding rubber material according to any one of claims 1 to 3, which is made into an antistatic coated fabric sheet by dipping, coating, friction coating, and topping. 5. Claim 1, in which a latex or liquid rubber coating layer is provided on the front and back layers and/or the side surfaces.
The electromagnetic wave shielding rubber material according to any one of Items 1 to 4. 6. The electromagnetic wave shielding rubber material according to any one of claims 1 to 5, wherein a pressure-sensitive adhesive layer or an adhesive layer is provided on a part or all of the front and back layers. 7. The electromagnetic wave shielding rubber material according to any one of claims 1 to 6, which is molded into a cylindrical body.