JPH0651378B2 - Coarse sheet with excellent transparency, breathability, sound transmission and electromagnetic wave shielding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic wave shielding coarse sheet. More specifically, the present invention has excellent transparency, air permeability, sound permeability, and stable electromagnetic wave shielding property, and also has excellent bending strength, flatness, low bulkiness, and installation surface. The present invention relates to a rough sheet which is excellent in conformability to.

[Prior art and problems to be solved by the invention]

Conventionally, flexible sheets made of various synthetic resins or natural or synthetic rubber materials have been used as covers for equipment, partitions, and other flexible covering materials. Among them, fiber materials are used. Many are also reinforced by. However, these conventional flexible sheets are generally electrically insulating and generally
It has a specific resistance value of 10 ¹⁰ to 10 ¹⁷ Ωcm, and most of these have a specific resistance value of 10 ¹² Ωcm or more. Therefore, when these conventional flexible sheets are rubbed, static electricity is generated, which makes it difficult to handle the flexible sheet, which may adversely affect electric and electronic devices.

Further, with the development and spread of electric and electronic devices, prevention of electric and electromagnetic interferences occurring in these devices and prevention of electrification have become important issues to be solved.

Conventionally, the electromagnetic wave shielding sheet material is generally a conductive non-permeable film or sheet having a flexible polymer material as a matrix, and these are not transparent, ventilated, and breathable, and also shield sound. It was a thing.

Wire mesh, metal mesh, etc. can be considered as another electromagnetic wave shielding sheet material, but these metallic materials are hard and have poor shape changeability, and moreover, they are easily cut by repeated bending, which makes the electromagnetic wave shielding property unstable. There is a problem such as becoming.

As another electromagnetic wave shielding sheet material, a fiber material obtained by plating or vapor depositing a conductive metal is also known, but these are extremely expensive and have limited practical applications. However, it was difficult to use as a partitioning material and a covering material.

Furthermore, conventional sheet materials for electromagnetic wave shielding are bulky and have poor flatness, and thus have a problem of low compatibility with an installation surface, and are often difficult to handle.

The subject of the present invention is excellent in transparency, breathability and sound permeability, and has stable electromagnetic wave shielding property, antistatic property and leakage preventive property, easy bending, and excellent in bending strength, and It is an object of the present invention to provide an electromagnetic wave shielding rough sheet which is inexpensive, has high flatness, is low in bulk, is easy to handle, and is easily adapted to the installation surface.

[Means and actions for solving the problem]

The rough sheet of the present invention, which is excellent in transparency, air permeability, sound permeability and electromagnetic wave shielding property, is composed of yarns including at least warp yarns arranged in parallel with each other with a gap between the yarns and weft yarns. Coarse woven base fabric, a matrix composed of a flexible polymer material, and a conductive coating layer containing a mixture of a conductive material as a main component and having a specific resistance value of 10 ⁵ Ωcm or less. In the sheet, the conductive coating layer covers at least the exposed surface of the yarns constituting the base fabric, and the yarns coated with the conductive coating layer are relative to the sheet plane. Has a flat cross-sectional shape, and the cross-sectional length (l ₁ ) of the covered yarn in a direction parallel to the sheet plane.
And the cross-sectional length (l ₂ ) in the direction perpendicular to the plane of the seat
The ratio (l ₁ ) / (l ₂ ) with the ratio is in the range of 1.3: 1 to 7: 1.

In the rough sheet of the present invention, the conductive coating layer may cover only the exposed surface of the yarn in the base fabric, and wrap around the intersections of the yarns and be integrally bound,
Alternatively, it may be one in which the entire surface of the yarn constituting the base cloth is covered.

Further, the rough sheet of the present invention contains a flexible polymer material having an insulating property as a main component, and an insulating coating layer having a specific resistance value of more than 10 ⁸ Ωcm is formed on the conductive coating layer. It may be

Further, the rough sheet of the present invention contains a mixture of a matrix made of a flexible polymer material and at least one selected from a conductive material and a semiconductive material as a main component, and 10 ² to 10 ⁸ A semiconductive coating layer having a specific resistance value in the range of Ωcm and higher than the specific resistance value of the conductive coating layer may be formed on the conductive coating layer.

The coarse woven base fabric used in the coarse sheet of the present invention is composed of yarns including warp yarns and weft yarns arranged in parallel with each other with a gap between the yarns, without a cloth. That is, the coarse base cloth may be a biaxial cloth composed of warp threads and weft threads, a biaxial cloth including other yarns, or a tetraaxial cloth.

There is no particular limitation on the structure of the coarse base fabric as described above, and it can be selected from coarse woven fabrics, knitted fabrics and woven and knitted fabrics. As such a coarse cloth, for example, a plain weave composed of warp yarn 1 and weft yarn 2 as shown in FIG. 1 and two weft yarns 3 as shown in FIG. 2 are two warp yarns 4a and 4b. As shown in FIG. 3, the warp weaves which are connected while being entangled with each other, or as shown in FIG. A leno weave or the like in which the warp yarns 6 and the weft yarns 5 are superposed so as to be perpendicular to each other and the warp yarns 6 and the weft yarns 5 are connected to each other is preferable.

The base fabric used in the present invention is coarse, and the warp yarn and the weft yarn form a gap of about 0.1 to about 10 mm between the yarns which are adjacent to each other in parallel. It is more preferable that the yarn gap be 0.1 to 5 mm.

That is, the area of the gap space formed between the warp and the weft is preferably about 0.01 to 10 mm ² , and 0.01 to 25 m.
More preferably m ² . Of course, the shape of the inter-thread space is not limited to a square shape, and may be any shape according to the base fabric structure.

In general, the base fabric used in the present invention is preferably one having a basis weight of 20 to 500 g / m ^2, more preferably has a basis weight of 40~300g / m ^2.

There is no particular limitation on the yarns constituting the coarse base fabric of the present invention, and natural fibers such as cotton and hemp, inorganic fibers such as glass fiber, regenerated fibers such as viscose rayon and cupra, Semi-synthetic fibers such as G- and tri-acetate fibers, and synthetic fibers such as nylon 6 fibers, nylon 66 fibers, polyester (polyethylene terephthalate etc.) fibers, water insolubilized polyvinyl alcohol fibers (vinylon), aromatic polyamide fibers, A fiber made of at least one fiber selected from those that can be used for forming a knitted fabric, such as aromatic polyester fiber, acrylic fiber, polyvinyl chloride fiber, and polyolefin fiber, is used. Further, the fiber yarn may be any of short fiber spun yarn, long fiber yarn, split yarn, tape yarn, monofilament yarn, etc., but capable of effectively carrying the polymeric material coating agent in a large amount as much as possible. Is preferred.

When a multifilament yarn is used as the yarn for the coarse base cloth, polyethylene terephthalate multifilament yarn (melting point = about 260) of 100 to 5000 denier is used.
℃) and vinylon, multifilament yarn (about 22
Pyrolysis at 0 to 230 ° C) is preferable because it has excellent strength.

In the rough sheet of the present invention, the rough base cloth may be covered with a conductive coating layer. In this case, the yarn constituting the coarse base cloth has its exposed peripheral surface covered with the conductive coating layer, and the yarn crossing points are wrapped by the conductive coating layer and integrally bound.

In the coarse sheet shown in FIG. 4, the warp threads 11 and the weft threads 12 intersecting each other are in direct contact with each other. The exposed peripheral surfaces of the warp yarn 11 and the weft yarn 12 are covered with a conductive coating layer 13, and the intersecting portion of the warp yarn 11 and the weft yarn 12 is wrapped in the conductive coating layer and is embarrassed and integrally bound and fixed. Therefore, it has excellent conductivity and prevents misalignment and thread slippage.

The rough sheet of the present invention may be composed of a yarn whose entire surface is coated with a conductive coating layer. In this case, the yarns come into contact with each other at the intersections of the yarns via the conductive coating layers that cover the yarns.

In the coarse sheet shown in FIG. 5, the warp yarn 11 and the weft yarn 12 are entirely covered with a conductive coating layer 13, and the warp yarn 11 and the weft yarn 12 are covered with the conductive coating layer 13 at the intersections thereof. Are in contact with each other through the conductive coating layer 13.

The conductive coating layer contains, as a main component, a mixture of a matrix made of a flexible (easily bent) polymer material and a conductive material dispersed in the matrix.

The flexible polymer material used as the matrix contains at least one selected from a flexible synthetic resin, a synthetic rubber, and a natural rubber, and a preferable synthetic resin is polyvinyl chloride. (PVC), polyurethane, ethylene-vinyl acetate copolymer, isotactic polypropylene, polyethylene, polyacrylonitrile, polyester, silicone, fluorine-containing polymer, polyamide and other known materials. Further, examples of preferable synthetic rubber include styrene-butadiene rubber (SB
R), chlorosulfonated polyethylene rubber, polyurethane rubber, butyl rubber, silicone rubber, fluorine-containing polymer rubber, isoprene rubber and other known materials.
The most preferred synthetic resin is PVC, which is a flexibilizer,
It may contain fillers, colorants, stabilizers and / or other modifiers.

Generally, the polymer material constituting the matrix preferably has a melting point at least 5 ° C., preferably 10 ° C. to 20 ° C. lower than the melting point or thermal decomposition temperature of the base fabric yarn.

The conductive material mixed in the matrix may be in the form of liquid, powder, fibrous, foil or cotton, and is generally carbon black, graphite, carbon fiber, metal such as Al, Au, Ag, Pt, Cu, Cr, Ni, Z
n, Ti, Pb, Sn, Pd, and alloys containing at least one of these, and powders of compounds, fibers, conductive compounds such as indium oxide powder, and various conductive amorphous metals and conductive metals It can be selected from plated amorphous metal powder, fibers and the like.

The content of the conductive material in the conductive coating layer is not particularly limited as long as the obtained conductive coating layer has the desired conductivity, but the specific conductivity, property, and desired conductivity value of the material. In general, it is preferably 5% by weight or more, and more preferably 10 to 70% by weight.
Of course, the content of the conductive material may be more than 70% by weight as long as the performance of the obtained conductive coating layer is not impaired.

The weight of the conductive coating layer is not particularly limited as long as it exhibits the desired performance, but it is generally 50% to 300% of the weight of the coarse base fabric.
%, And more preferably 70 to 200%.

To form a conductive coating layer, a coating solution containing a predetermined amount of a matrix polymer material and a conductive material, or a dipping method of immersing the coarse base cloth in an emulsion, and squeezing to a predetermined degree,
Alternatively, a spraying method, a coating method, a brushing method, or another known method can be used.

The coating solution or emulsion contains, in addition to the matrix polymer material and the conductive material, conventional additives such as flame retardants (eg antimony trioxide), antifouling color pigments,
It may contain an antioxidant, an ultraviolet absorber, and other additives. Further, desired characters and patterns may be imparted to the rough sheet of the present invention with ink, pigment, dye or the like. Furthermore, it is easy to apply various chemicals such as antifouling agents to the sheet of the present invention to add desired performance.

In the rough sheet of the present invention, the conductive coating layer is 10 ⁵ Ωcm
The following, preferably 10 ¹ Ωcm or less, more preferably 10 ⁰
Has a specific resistance value of Ωcm or less, and is generally 10 ⁰ to 10 ^-3 Ωcm
It has a specific resistance value of.

When the resistivity of the conductive coating layer is higher than 10 ⁵ Ωcm,
The resulting rough sheet has insufficient electromagnetic wave shielding properties.

In the rough sheet of the present invention, the conductive coating layer 13 may be further coated with an insulating coating layer 14 as shown in FIG. 6, for example. The insulative coating layer is formed from an electrically insulative flexible polymer material as a main component, and the polymer material is selected from the polymer materials forming the matrix of the electrically conductive coating layer. be able to. The insulating coating layer may be formed only on the exposed surface of the conductive coating layer-covered yarn, or may be formed on the entire surface thereof. Generally, the former is preferable.

Insulating coating layer is higher than 10 ⁸ Ωcm, preferably 10 ¹⁰ Ωcm
Above, more preferably, it has a specific resistance value of 10 ¹² Ωcm or more. The insulating coating layer is effective for preventing electric leakage in the rough sheet of the present invention. If the specific resistance value of the insulating coating layer is 10 ⁸ Ωcm or less, the effect of preventing leakage of electric current from the resulting rough sheet becomes insufficient.

The rough sheet of the present invention has a semiconductive coating layer covering the conductive coating layer 13 as shown in FIG. 6, for example.
It may have 14. Of course, the semiconductive coating layer may be formed only on the exposed surface of the conductive coating layer,
Alternatively, it may be formed on the entire surface of the yarn.

The semiconductive coating layer contains, as a main component, a mixture of a matrix made of a flexible polymer material and at least one kind selected from a conductive material and a semiconductive material dispersed in the matrix. The flexible polymer material can be selected from the flexible polymer materials for forming the matrix of the conductive coating layer, and the conductive material can be selected from the conductive material for the conductive coating layer. it can. Further, the semiconductive material can be selected from liquid, powder, fibrous and foil silver bromide, silicon, germanium, conductive organic compounds and the like.

The conductive organic compound is, for example, a polycarboxylic acid ester compound of mono- and poly-alkylene glycol monoalkyl ether, and includes, for example, the following general formulas (I), (II) and (III): (However, in the above formula, X represents a member selected from aliphatic, alicyclic and aromatic polybasic acid residues with and without a substituent having 2 to 8 carbon atoms, and Y is an epoxy. Represents a member selected from a cyclohexane ring having a substituted or not, wherein Z is selected from an aliphatic, alicyclic and aromatic polybasic carboxylic acid residue having 2 to 22 carbon atoms. A ₁ , A ₂ , A ₃ , A ₄ and A
₅ each independently represents a member selected from an alkylene group having 2 to 4 carbon atoms, and R ₁ , R ₂ , R ₃ , R ₄ and R ₅ each independently represent a straight chain having 1 to 15 carbon atoms. Represents a member selected from chain and branched chain alkyl groups,
However, the total number of carbon atoms N of A ₁ and R ₂ , A ₂ , R ₂ and R ₃ and R ₃ is 5 to 17, and m ₁ , m ₂ , m ₃ and m ₄ are independently of each other. , An integer of 1 to 7,
n ₁ represents an integer of ₁ to 5, n ₂ is 1 or 3 to
Represents an integer of 6, l represents an integer of 1 to 7, n ₂
Is 3 to 6, 1 and R ₅ in the n ₂ COO (A ₅ O) lR ₅ groups may be the same or different from each other. ) Includes a group of compounds.

The mono- and poly-alkylene glycol monoalkyl ethers used in the production of the above conductive ester compounds include propanol and 1 to 7 mol of ethylene oxide, propylene oxide 1 to 4 or butylene oxide 1.
Addition compound with 3 to 3 mol: butanol with 1 to 6 mol of ethylene oxide, 1 to 4 mol of propylene oxide or 1 to 3 mol of butylene oxide: hexanol with 1 to 5 mol of ethylene oxide, 1 to 3 mol of propylene oxide or Addition compound with 1 to 2 mol of butylene oxide: 1 to 5 mol of heptanol and ethylene oxide, 1 to 3 mol of propylene oxide or 1 to 1 of butylene oxide.
Addition compound with 2 moles: Addition compound with octanol and ethylene oxide 1 to 4 moles, propylene oxide 1 to 3 moles or butylene oxide 1 to 2 moles: nonanol and ethylene oxide 1 to 4 moles, propylene oxide 1 to
Addition compound of 2 mol or 1 to 2 mol of butylene oxide: Decanol and 1 to 3 mol of ethylene oxide, 1 to 2 mol of propylene oxide or 1 mol of butylene oxide: Dodecanol and 1 to 2 ethylene oxide.
Addition compound with 1 mol of propylene oxide or 1 mol of propylene oxide: 1-2 mol of tridecanol and ethylene oxide, 1 mol of propylene oxide or 1 mol of butylene oxide: tetradecanol and 1 mol of ethylene oxide, 1 mol of propylene oxide And an addition compound of pentadecanol and 1 mol of ethylene oxide.

Examples of the dicarboxylic acid used in the production of the conductive ester compound of the above formula (I) include adipic acid, azelaic acid, sebacic acid, succinic acid, brassic acid, tetrahydrophthalic acid and phthalic acid.

Further, as the carboxylic acid used in the production of the conductive ester compound of the formula (II) and (III), a monocarboxylic acid, a trivalent or higher polycarboxylic acid or a divalent carboxylic acid having an epoxycyclohexane ring is used. is there. These carboxylic acids may have a lower alkyl group such as a methyl group and an ethyl group, a hydroxyl group, and a substituent containing a hetero atom such as oxygen, silicon and halogen.

As the monocarboxylic acid, an aliphatic monocarboxylic acid having 2 to 22 carbon atoms can be used. Further, the polybasic acid is an aliphatic, alicyclic or aromatic polybasic acid consisting of a carboxylic acid residue having 3 to 8 carbon atoms, and specifically, citric acid, aconitic acid, butanetricarboxylic acid, butane. Aliphatic carboxylic acids such as tetracarboxylic acids, alicyclic carboxylic acids such as epoxyhexahydrophthalic acid, aromatic polycarboxylic acids such as trimellitic acid and pyromellitic acid, and acid anhydrides of these carboxylic acids Etc. can be used. These carboxylic acids may be used alone or as a mixture of two or more kinds.

The semiconductive coating layer is effective for both the leakage prevention and the electrostatic electrification prevention of the coarse sheet of the present invention, and 10 ⁸ to 1
0 ² Ωcm, preferably 10 ⁸ to 10 ⁵ Ωcm, more preferably 10 ⁷
It has a specific resistance value of ~ 10 ⁶ Ωcm. When the specific resistance value of the semiconductive coating layer is higher than 10 ^8, it exhibits electrical insulation and the antistatic effect is insufficient, and 10 ² Ωc
If it is lower than m, the whole will show conductivity and the effect of preventing leakage will be insufficient.

There is no particular limitation on the weight and thickness of the insulating coating layer and the semiconductive coating layer as long as they meet the intended use and purpose. Generally, the weight is preferably in the range of 1 to 50%, and more preferably 5 to 30%, based on the weight of the base fabric.

The rough sheet of the present invention, as described above, has a rough base cloth and at least a conductive coating layer, and generally,
A base cloth made of a coarse cloth is coated with a conductive coating material to be manufactured. However, the sackcloth sheet of the present invention has at least a conductive coating layer formed on the entire surface of the yarn, and the obtained conductive coating layer-coated yarn is woven / knitted into a coarse sheet having a desired coarse structure. -Or may be woven or knitted.

Generally, the insulating coating layer or the semiconductive coating layer is preferably formed on the exposed surface of the conductive coating layer of the base fabric having the conductive coating layer.

In the rough sheet of the present invention, at least one of the conductive coating layer and, if necessary, the insulating coating layer and the semiconductive coating layer may be a porous body. The porous coating layer is
It is effective in controlling the flexibility, flexibility and cushioning property of the coarse sheet to desired levels.

In the coarse sheet of the present invention, the yarn covered with the coating layer containing the flexible polymer material has a flat cross-sectional shape with respect to the plane of the sheet. In this flat cross-sectional shape, the cross-sectional length (l ₁ ) in the direction parallel to the seat plane,
The ratio (l ₁ ) / (l ₂ ) to the sectional length (l ₂ ) in the direction perpendicular to the sheet plane is within the range of 1.3: 1 to 7: 1. The sheet having such a flat cross section is excellent in handleability due to its excellent flatness, low bulkiness, and excellent conformability to an installation surface.
Such a flat yarn sheet may be obtained by applying a pressure flattening treatment to a coating sheet obtained by coating the coarse base cloth with a predetermined coating layer. Further, in order to achieve the flattening of the yarn without positively pressing and flattening the yarn, a yarn suitable for the flattening, for example, a non-twisted yarn composed of multifilaments or a sweet twisted yarn, or 2 The number of twists may be equal to or more than one of these yarns, or a twisted yarn.
Multifilament yarn of 120 t / m or less, especially 100 twists
It is preferable to use one having a t / m or less, for example, one having 50 to 100 t / m. However, the yarn suitable for flattening is not limited to the above, and may be, for example, a spun yarn, or one originally having a flat cross-sectional shape as a fiber assembly, that is, two or more. Alignment thread of the yarn,
Alternatively, a sweet twisted yarn or the like may be used to produce a coarse base fabric using an uncoated yarn having the flat cross-sectional shape as described above, and a predetermined coating may be applied to the coarse base fabric.

The rough sheet of the present invention can be heat bonded depending on the characteristics of the polymer material in the coating layer forming the surface thereof.
Further, the density of the warp yarns and / or the weft yarns of both ears of the coarse sheet or the portion to be sewn may be made higher than the densities of the other portions to increase the shear adhesive strength of this portion.

Further, the weft yarns of the coarse sheet of the present invention may be curved in an arc shape, thereby increasing the shear adhesive strength of the heat-bonded portion.

〔Example〕

The electromagnetic wave shielding rough sheet of the present invention will be further described by the following examples.

Example 1 Polyester multifilament yarn Two warp yarns were used as wefts to prepare a warp weave having a design as shown in FIG. The structure is as follows, and the size of the inter-filament gap was 3.5 mm × 3.5 mm on average.

This rough base cloth is made up of the following composition: PVC 100 parts by weight Copper powder 50 〃 DOP (plasticizer) 80 〃 Stabilizer 1 〃 Antimony oxide (flame retardant) 30 〃 Pigment (green) 2 〃 Triclen 50 〃 Polymer composition The composition was immersed in a treatment liquid, squeezed, dried and gelled, and the composition was sufficiently adhered to the rough base cloth. As a result, 100% by weight of the conductive cloth was attached to the base cloth.

The specific resistance value of this conductive coating layer is 10 ^-2 Ωcm, and the ratio (l ₁ ) / (l ₂ ) in the cross section of the coated yarn is 2.0: 1.
Met.

The obtained rough sheet not only showed good electromagnetic wave shielding properties, but also had good ventilation / ventilation properties, see-through properties and sound permeability properties, and was easy to fit on the installation surface and easy to handle.

Example 2 The same operation as in Example 1 was performed. However, an insulating coating composition having the following composition: 100 parts by weight of PVC DOP 80 〃 stabilizer 1 〃 antimony oxide 30 〃 green pigment 2 〃 trichlene 50 〃 is formed on the conductive coating layer. Solidify to 15
% Insulating coating layer was formed.

The specific resistance value of the obtained insulating coating layer is 10 ¹⁴ Ωcm,
The ratio (l ₁ ) / (l ₂ ) in the cross section of the coated yarn is 2.
It was 4: 1.

Further, the obtained rough sheet showed a good electromagnetic wave shielding property, a further excellent ventilation / ventilation property, a see-through property and a sound permeability property, and was easy to be fitted to the installation surface and easy to handle.

Example 3 The same operation as in Example 1 was performed. However, a semiconductive coating liquid having the following composition: 100 parts by weight of PVC DOP 80 〃 stabilizer 1 〃 antimony oxide 30 〃 green pigment 2 〃 carbon black 8 〃 trichlene 50 〃 is formed on the conductive coating layer. 15% of the weight of the base cloth
The semiconductive coating layer of was formed. The specific resistance value of this semiconductive coating layer was 10 ⁶ Ωcm, and the ratio (l ₁ ) / (l ₂ ) in the cross section of the coated yarn was 2.5: 1.

The obtained rough sheet has good electromagnetic wave shielding properties, satisfactory leakage preventive property and antistatic property, and further has good ventilation, transparency and sound permeability, and fits well on the installation surface. However, it was easy to handle.

Example 4 The same operation as in Example 1 was performed. However, as a coarse base fabric,
The following structure consisting of water-insolubilized polyvinyl alcohol fiber (vinylon) spun yarn: The coarse plain weave fabric of was used. In the obtained coarse sheet,
The adhesion weight of the conductive coating layer was as high as 120% of the weight of the base cloth, and its specific resistance value was 10 ^-2 Ωcm. The coated coarse sheet was flattened by a pair of squeezing rolls in the step of applying the conductive coating layer. The ratio (l ₁ ) / (l ₂ ) in the cross section of the coated yarn was 4: 1.

In addition, this rough sheet has good electromagnetic shielding properties, ventilation and
It had ventilation, transparency, and sound permeability, had good compatibility with the installation surface, was easy to handle, and had high durability.

Example 5 Polyester multifilament yarn (1000d / 192
A thread having a conductive coating layer was obtained by squeezing f) through a melt having the following composition with a die.

PVC 100 parts by weight Copper powder 50 〃 The solid weight of the conductive coating layer was 70% with respect to the yarn weight, and its specific resistance value was 10 ^-2 Ωcm. Using this coated yarn, a plain woven fabric having a density of 7 × 7 yarns / inch was prepared. (Gap between yarns 3.5mm x 3.5mm) This plain fabric is heated to about 140 ° C and lightly pressed through a pair of press rolls at room temperature to flatten the yarns and press the joining points of the yarns. I temporarily fixed it. The obtained coarse sheet has a yarn-to-yarn gap of about 3.0 mm × 3.0 mm, the ratio (l ₁ ) / (l ₂ ) in the cross section of the coated yarn is 3: 1, and the fixing of the yarn is also performed. It was good, and the handling property of the rough sheet, the conformability to the installation surface, and the electromagnetic wave shielding property were also good.

Example 6 With respect to the plain woven fabric having the conductive coating layer obtained in Example 5, an insulating coating layer having the same composition as that described in Example 2 was formed with an adhesion amount of 10% (weight). The ratio (l ₁ ) / (l ₂ ) in the cross section of the coated yarn was 2.8: 1. The properties of the obtained rough sheet, particularly the conformability to the installation surface and the electromagnetic wave shielding property were good as in Example 2.

Example 7 With respect to the plain woven fabric having the conductive coating layer obtained in Example 5, a semiconductive coating layer having the same composition as that described in Example 3 was formed with an adhesion amount of 10% (weight). The ratio (l ₁ ) / (l ₂ ) in the cross section of the coated yarn was 2.5: 1.
The properties of the obtained rough sheet, particularly the electromagnetic wave shielding property, were good as in Example 3.

[Brief description of drawings]

FIG. 1, FIG. 2 and FIG. 3 are explanatory views showing an example of the structure of the rough base cloth of the rough sheet of the present invention, and FIG. 4, FIG. 5 and FIG. FIG. 7 is a cross-sectional explanatory view showing a covering state of a covering layer at a yarn intersection of one embodiment of the electromagnetic wave shielding coarse sheet, and FIG. 7 is a flat cross section of the covering yarn of the electromagnetic wave shielding coarse sheet of the present invention. It is explanatory drawing which shows an example. 1, 4a, 4b, 6, 11 ... Warp, 2, 3, 5, 12 ... Weft, 7 ... Entangled thread, 13 ... Conductive coating layer, 14 ... Insulating or semi-conductive coating layer.

Claims (5)

[Claims] 1. A coarse woven fabric-like base fabric composed of yarns including at least warp yarns arranged in parallel with each other with a yarn gap therebetween and weft yarns, and a matrix made of a flexible polymer material. And a conductive sheet containing a mixture of a conductive material as a main component, and a conductive coating layer having a specific resistance value of 10 ⁵ Ωcm or less, wherein the conductive coating layer constitutes the base fabric. A yarn that covers at least the exposed surface of the yarn that is covered with the conductive coating layer has a flat cross-sectional shape with respect to the plane of the sheet, and the coated yarn is a sheet. The ratio (l ₁ ) / (l ₂ ) of the sectional length (l ₁ ) in the direction parallel to the plane to the sectional length (l) ₂ in the direction perpendicular to the sheet plane is 1.3: 1 to 7: 1.
Coarse sheet with excellent transparency, breathability, sound permeability and electromagnetic wave shielding property within the range of. 2. The rough sheet according to claim 1, wherein the conductive coating layer covers only the exposed surface of the yarn in the base fabric, and wraps around the intersection of the yarn and is integrally bound. . 3. The rough sheet according to claim 1, wherein the conductive coating layer covers the entire surface of the yarns constituting the base cloth. 4. An insulating coating layer containing a flexible polymer material having an insulating property as a main component and having a specific resistance value larger than 10 ⁸ Ωcm is formed on the conductive coating layer.
The coarse sheet according to claim 1. 5. A mixture containing, as a main component, a matrix made of a flexible polymer material and at least one selected from a conductive material and a semiconductive material, and 10 ² to 10 ⁸
A semi-conductive coating layer having a specific resistance value in the range of Ωcm and higher than the specific resistance value of the conductive coating layer,
The rough sheet according to claim 1, which is formed on the conductive coating layer.