Electromagnetic wave shielding fabric and fabric with resin

Abstract

The problem to be solved by the present invention is to provide an electromagnetic wave shielding fabric capable of achieving excellent electromagnetic wave shielding properties while also obtaining superior resin affinity. The present invention provides an electromagnetic wave shielding fabric (1) comprising a plurality of warp threads (3) extending in the Y-axis direction and arranged in the X-axis direction intersecting the Y-axis direction, and a plurality of weft threads (5) extending in the X-axis direction and arranged in the Y-axis direction, wherein the warp threads (3) and weft threads (5) are formed from conductive threads (71) and non-combustible threads, a plurality of surrounding regions (A) are formed enclosed by the conductive threads (71) adjacent to each other in the Y-axis direction and the conductive threads (71) adjacent to each other in the X-axis direction, and the average area of the surrounding regions (A) as viewed from the Z-axis direction, which is orthogonal to both the X-axis direction and the Y-axis direction, is 0.075 to 2.000 mm2.

Description

Electromagnetic wave shielding fabric and resin-coated fabric

[0001] One aspect of the present invention relates to an electromagnetic wave shielding fabric, a resin-coated fabric, and the like.

[0002] In recent years, there has been concern about the effects of electromagnetic waves on the human body, and there is a demand for members for shielding electromagnetic waves. For example, Patent Document 1 listed below discloses a woven fabric using conductive yarn (conductive fiber) as a member for shielding electromagnetic waves.

[0003] Japanese Patent Application Publication No. 11-50352

[0004] Impregnating a substrate such as a woven fabric with a resin material can improve various properties, such as mechanical properties. However, according to the knowledge of the present inventors, it is sometimes difficult to obtain excellent resin affinity for resin materials in conventional members for shielding electromagnetic waves. Therefore, members for shielding electromagnetic waves are required to have excellent resin affinity while also obtaining excellent electromagnetic wave shielding properties.

[0005] An object of one aspect of the present invention is to provide an electromagnetic wave shielding fabric that can achieve excellent electromagnetic wave shielding properties and excellent resin affinity.An object of another aspect of the present invention is to provide a resin-coated fabric that includes such an electromagnetic wave shielding fabric.

[0006] In some aspects, the present invention relates to the following [1] to [6], etc. [1] A fabric comprising a plurality of warp yarns extending in a first direction and arranged in a second direction intersecting the first direction, and a plurality of weft yarns extending in the second direction and arranged in the first direction, the warp yarns and the weft yarns being formed of at least one of conductive yarns and non-flammable yarns, a plurality of surrounded regions are formed by the conductive yarns adjacent to each other in the first direction and the conductive yarns adjacent to each other in the second direction, and the average area of ​​the surrounded regions when viewed from a third direction perpendicular to both the first direction and the second direction is 0.075 to 2.000 mm ２ [2] The average area of ​​the surrounding region is 0.309 to 0.532 mm ２[3] The electromagnetic wave shielding fabric according to [1], wherein at least one of the warp yarns and the weft yarns is a plied yarn obtained by pliedly twisting the conductive yarn and the nonflammable yarn. [4] The electromagnetic wave shielding fabric according to [3], wherein the warp yarns and the weft yarns are the plied yarns, and the conductive yarns adjacent to each other in the first direction and the conductive yarns adjacent to each other in the second direction are the conductive yarns of the plied yarns. [5] The electromagnetic wave shielding fabric according to any one of [1] to [4], wherein at least one of the warp yarns and the weft yarns includes a metal-coated yarn in which a core yarn is coated with a metal material, the core yarn being made of an organic material, and the nonflammable yarn being made of glass. [6] A resin-attached fabric comprising the electromagnetic wave shielding fabric according to any one of [1] to [5], and a resin part attached to at least a part of the electromagnetic wave shielding fabric.

[0007] According to one aspect of the present invention, there is provided an electromagnetic wave shielding fabric that can achieve excellent electromagnetic wave shielding properties and excellent resin affinity. According to another aspect of the present invention, there is provided a resin-coated fabric that includes such an electromagnetic wave shielding fabric.

[0008] Fig. 1 is a plan view showing part of the configuration of one example of an electromagnetic shielding fabric. Fig. 2 is a plan view showing part of ply-twisted yarns forming the warp and weft yarns of the electromagnetic shielding fabric of Fig. 1. Fig. 3 is a view of part of a surrounded region formed on the front side of the electromagnetic shielding fabric of Fig. 1, viewed from above in the Z-axis direction. Fig. 4 is a view of part of a surrounded region formed on the back side of the electromagnetic shielding fabric of Fig. 1, viewed from above in the Z-axis direction. Fig. 5 is a plan view showing part of the configuration of another example of an electromagnetic shielding fabric.

[0009] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to these embodiments in any way.

[0010] In this specification, a numerical range indicated using "to" indicates a range that includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this specification, the upper or lower limit of a numerical range in a certain stage can be arbitrarily combined with the upper or lower limit of a numerical range in another stage. In the numerical ranges described in this specification, the upper or lower limit of the numerical range may be replaced with a value shown in the examples. "A or B" may include either A or B, or may include both. Unless otherwise specified, the materials exemplified in this specification can be used alone or in combination of two or more. "(Meth)acrylic" means at least one of acrylic and the corresponding methacrylic.

[0011] The electromagnetic wave shielding fabric (hereinafter sometimes simply referred to as "fabric") according to this embodiment comprises a plurality of warp yarns extending in a first direction and arranged in a second direction intersecting the first direction, and a plurality of weft yarns extending in the second direction and arranged in the first direction. In the fabric according to this embodiment, the warp yarns and weft yarns are formed of at least one of conductive yarns and non-flammable yarns, and a plurality of enclosed regions are formed by the conductive yarns adjacent to each other in the first direction and the conductive yarns adjacent to each other in the second direction. In the fabric according to this embodiment, the average area of ​​the enclosed regions when viewed from a third direction perpendicular to both the first direction and the second direction is 0.075 to 2.000 mm. ２ is.

[0012] The woven fabric according to this embodiment has excellent resin affinity for resin materials, and can satisfactorily impregnate the woven fabric with resin materials in the thickness direction or coat the woven fabric surface with resin materials. The woven fabric according to this embodiment can be rated, for example, as "A" in the evaluation described in the examples below.

[0013] The woven fabric according to this embodiment can be used to shield electromagnetic waves. The shielding mode may be absorption, scattering, reflection, etc. The electromagnetic wave shielding property can be measured by the KEC method, the DFFC method, or the free space method depending on the frequency of the electromagnetic waves.

[0014] The woven fabric according to this embodiment can achieve excellent electromagnetic wave shielding properties, and can achieve excellent electromagnetic wave shielding properties at 15 GHz. In the evaluation described in the Examples below, the woven fabric according to this embodiment can achieve an average electromagnetic wave shielding property in the warp direction and weft direction at 15 GHz of, for example, 18.0 dB or more (preferably, 20.0 dB or more, 22.0 dB or more, 24.0 dB or more, 25.0 dB or more, 26.0 dB or more, 28.0 dB or more, 28.5 dB or more, 30.0 dB or more, 31.0 dB or more, etc.).

[0015] According to one aspect of the woven fabric of this embodiment, excellent electromagnetic wave shielding properties can be obtained over a wide range of frequencies, including 100 KHz to 1 THz, 100 KHz to 200 GHz, 100 KHz to 100 GHz, 100 KHz to 30 GHz, 100 KHz to 10 GHz, 100 KHz to 500 MHz, 100 KHz to 10 MHz, 10 MHz to 1 THz, 10 MHz to 200 GHz, 10 MHz to 100 GHz, 10 MHz to 30 GHz, 10 MHz to 10 GHz, 10 MHz to 500 MHz, and 500 MHz to 1 It may be used for electromagnetic wave shielding in frequency bands such as 1 THz, 500 MHz to 200 GHz, 500 MHz to 100 GHz, 500 MHz to 30 GHz, 500 MHz to 10 GHz, 10 GHz to 1 THz, 10 GHz to 200 GHz, 10 GHz to 100 GHz, 10 GHz to 30 GHz, 30 GHz to 1 THz, 30 GHz to 200 GHz, 30 GHz to 100 GHz, 100 GHz to 1 THz, and 100 GHz to 200 GHz.

[0016] According to one aspect of the woven fabric of this embodiment, in the evaluation described in the examples below, the average value of the electromagnetic wave shielding properties in the warp direction and weft direction at 100 kHz can be, for example, 35 dB or more (preferably, 40.0 dB or more, 44.0 dB or more, 45.0 dB or more, 45.5 dB or more, 46.0 dB or more, etc.).

[0017] According to one aspect of the woven fabric of this embodiment, in the evaluation described in the examples below, the average value of the electromagnetic wave shielding properties in the warp direction and weft direction at 100 MHz can be, for example, 35 dB or more (preferably, 40.0 dB or more, 44.0 dB or more, 45.0 dB or more, 45.5 dB or more, 46.0 dB or more, etc.).

[0018] According to one aspect of the woven fabric of this embodiment, in the evaluation described in the examples below, the average value of the electromagnetic wave shielding properties in the warp direction and weft direction at 1 GHz can be, for example, 25 dB or more (preferably, 30.0 dB or more, 35.0 dB or more, 37.0 dB or more, 38.0 dB or more, 39.0 dB or more, etc.).

[0019] According to one aspect of the woven fabric of this embodiment, in the evaluation described in the examples below, the average value of the electromagnetic wave shielding properties in the warp direction and weft direction at 40 GHz can be, for example, 10 dB or more (preferably, 12.0 dB or more, 15.0 dB or more, 16.0 dB or more, 18.0 dB or more, etc.).

[0020] According to one aspect of the woven fabric of this embodiment, in the evaluation described in the examples below, the average value of the electromagnetic wave shielding property in the warp direction and weft direction at 110 GHz can be, for example, 3.0 dB or more (preferably, 4.0 dB or more, 5.0 dB or more, 6.0 dB or more, 7.0 dB or more, etc.).

[0021] According to one aspect of the woven fabric of this embodiment, it is possible to reduce the ratio D / A ([difference D / average value A] x 100) of the difference D in the electromagnetic shielding properties in the warp direction and the weft direction to the average value A of the electromagnetic shielding properties in the warp direction and the weft direction. The smaller the ratio D / A, the smaller the variation between the electromagnetic shielding properties in the warp direction and the electromagnetic shielding properties in the weft direction, making it easier to shield electromagnetic waves in a suitable manner. According to one aspect of the woven fabric of this embodiment, in the evaluation described in the examples below, it is possible to obtain a D / A ratio at 100 kHz of, for example, 5.0% or less (preferably, 4.0% or less, 3.0% or less, 2.0% or less, 1.0% or less, etc.), a D / A ratio at 100 MHz of, for example, 5.0% or less (preferably, 4.0% or less, 3.0% or less, 2.0% or less, 1.0% or less, etc.), and a D / A ratio at 1 GHz of, for example, 50.0% or less (preferably, 45.0% or less, 42.0% or less, 35.0% or less, 30.0% or less, etc.). It is possible to obtain a D / A ratio of, for example, 20.0% or less (preferably, 18.0% or less, 16.0% or less, 10.0% or less, 5.0% or less, etc.) at 15 GHz, it is possible to obtain a D / A ratio of, for example, 10.0% or less (preferably, 8.0% or less, 6.0% or less, 5.0% or less, etc.) at 40 GHz, and it is possible to obtain a D / A ratio of, for example, 20.0% or less (preferably, 18.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, etc.) at 110 GHz.

[0022] According to one aspect of the woven fabric of this embodiment, excellent flame retardancy can be obtained. According to one aspect of the woven fabric of this embodiment, a rating of "A" can be obtained in the evaluation described in the examples below.

[0023] The resin-coated fabric (resin composite) according to this embodiment includes the fabric (electromagnetic wave shielding fabric) according to this embodiment and a resin portion attached to at least a portion of the fabric. The resin portion is formed of a resin material. The resin portion may be attached to at least one surface of the electromagnetic wave shielding fabric. Furthermore, the resin portion may be impregnated into the electromagnetic wave shielding fabric, from the viewpoint of easily improving the mechanical strength, handleability, or weather resistance of the resin-coated fabric. Examples of resin materials include polyester, (meth)acrylic resin, polyurethane, polyamide, polyolefin, vinyl acetate resin, epoxy resin, polyvinyl alcohol, polyvinyl chloride, fluororesin, and silicone resin. The resin portion may contain components other than the resin material. Examples of such components include inorganic particles, thickeners, surfactants, lubricants, pigments, dyes, flame retardants, UV absorbers, antistatic agents, antibacterial agents, antifungal agents, plasticizers, curing accelerators, and polymerization initiators. The method for producing the resin-coated fabric (resin composite) according to this embodiment includes a step of bringing at least a portion of the fabric (electromagnetic wave shielding fabric) according to this embodiment into contact with a resin material.

[0024] The resin-coated fabric (resin composite) according to this embodiment has excellent electromagnetic wave shielding properties, and can therefore be used as an electromagnetic wave shielding material for buildings (sports facilities, event venues, airport facilities, etc.), an electromagnetic wave shielding material for structures, an electromagnetic wave shielding material for tents, an electromagnetic wave shielding material for preventing wireless interference, an electromagnetic wave shielding material for preventing electromagnetic waves at drone practice ranges, an electromagnetic wave sealing material for mobility (automobiles, airplanes, etc.), and the like.

[0025] The woven fabric according to this embodiment comprises a plurality of warp yarns extending in a first direction and arranged in a second direction, and a plurality of weft yarns extending in the second direction and arranged in the first direction, the warp yarns and the weft yarns being formed of at least one of conductive yarns and non-flammable yarns. The second direction intersects with the first direction and may intersect with the first direction at an angle of 60 to 90 degrees (acute angle or right angle). The second direction may be perpendicular to the first direction.

[0026] The conductive yarn is a yarn having electrical conductivity. The electrical resistance (25°C) of the conductive yarn may be in the following range. －５ Ω / m or more, 10 －３Ω / m or more, or 10 －１ The electrical resistance may be 10 Ω / m or more. ９ Ω / m or less, 10 ７ Ω / m or less, or 10 ５ From these viewpoints, the electrical resistance may be 10 －５ ~10 ９ Ω / m, 10 －３ ~10 ９ Ω / m, 10 －１ ~10 ９ Ω / m, 10 －５ ~10 ７ Ω / m, 10 －３ ~10 ７ Ω / m, 10 －１ ~10 ７ Ω / m, 10 －５ ~10 ５ Ω / m, 10 －３ ~10 ５ Ω / m or 10 －１ ~10 ５ The electrical resistance of the conductive yarn can be measured according to IEC 63203-201-1:2022.

[0027] The conductive yarn contains a conductive material. Examples of the conductive material include metal materials and carbon materials. Examples of the metal material include silver, copper, nickel, tin, and stainless steel. The conductive yarn may contain silver, which facilitates obtaining excellent electromagnetic wave shielding properties, conductivity, or biocompatibility.

[0028] The conductive yarn may be a metal-coated yarn in which a core yarn is coated with a metal material. The core yarn may be a conductive yarn or a non-conductive yarn. The core yarn may be made of an organic material. The core yarn made of an organic material may be an organic fiber multifilament yarn or an organic fiber spun yarn, and may be an organic fiber multifilament yarn from the viewpoint of ease of compounding with a non-flammable yarn. The core yarn may be made of an inorganic material from the viewpoint of ease of achieving non-flammability. The core yarn made of an inorganic material may be an inorganic fiber multifilament yarn or an inorganic fiber spun yarn, and may be an inorganic fiber multifilament yarn from the viewpoint of ease of compounding with a non-flammable yarn. Examples of metal materials for the metal-coated yarn include the metal materials exemplified above. Methods for coating metal materials include electroless plating and covering with metal fibers. Examples of organic materials include nylon, polyester, (meth)acrylic resin, rayon, aramid, polyurethane, polyolefin (polyethylene, polypropylene, etc.), and the like. The organic material may be nylon, which can easily achieve both excellent electromagnetic wave shielding properties and resin affinity. Examples of inorganic materials include glass, basalt, ceramic, etc. The core yarn of the metal-coated yarn may be made of an organic material, which is lightweight and flexible and therefore has excellent secondary processability, and may be made of at least one material selected from the group consisting of nylon, polyester, (meth)acrylic resin, and rayon, or may be made of nylon.

[0029] At least one of the warp and weft threads may include a metal-coated thread as a conductive thread, from the viewpoint of easily obtaining excellent electromagnetic wave shielding properties, or may include a metal-coated thread having a core thread formed from an organic material, or may include a metal-coated thread having a nylon thread coated with silver (e.g., silver-plated nylon thread).

[0030] The non-flammable yarn is a yarn that has non-flammability. The non-flammable yarn is a yarn that, in the evaluation of non-flammability according to ISO 5660-1 (heat generation test) in the examples described later, gives a grade of "A" to a fabric made only from the yarn to be evaluated (a fabric obtained by plain weaving the yarn to be evaluated as the warp and weft at a warp density of 28 / 25.4 mm and a weft density of 28 / 25.4 mm).

[0031] The non-combustible yarn may be a yarn that does not fall under the category of the conductive yarn described above, and may be a non-conductive yarn. The electrical resistance (25°C) of the non-combustible yarn may be in the following range. ９ Ω / m, and may exceed 10 １０ The electrical resistance may be 10 Ω / m or more. １4 From these viewpoints, the electrical resistance may be 10 ９ Ω / m over 10 １4 Ω / m or less, or 10 １０ ~10 １4 It may be Ω / m.

[0032] Examples of materials constituting the non-flammable yarn include glass and aramid. The non-flammable yarn may be made of glass from the viewpoint of excellent light transmittance. The non-flammable yarn made of glass may be a long glass fiber multifilament or a short glass fiber spun yarn, and from the viewpoint of ease of compounding with conductive yarn, may be a glass fiber multifilament yarn. From the viewpoint of easily achieving both excellent electromagnetic wave shielding properties and resin affinity, the woven fabric according to this embodiment may be in an embodiment in which at least one of the warp yarn and the weft yarn includes a metal-coated yarn in which a core yarn is coated with a metal material, the core yarn is made of an organic material, and the non-flammable yarn is made of glass.

[0033] The fineness (unit [tex]: hereinafter, the unit will be omitted in some cases) of the conductive yarn (conductive fiber) may be within the following ranges, from the viewpoint of easily achieving both excellent electromagnetic wave shielding properties and resin affinity. The fineness of the conductive yarn may be 1.0 or more, 3.0 or more, 5.0 or more, 8.0 or more, 10.0 or more, or 12.0 or more. The fineness of the conductive yarn may be 60.0 or less, 55.0 or less, 50.0 or less, 45.0 or less, 40.0 or less, 35.0 or less, or 30.0 or less. From these viewpoints, the fineness of the conductive yarn may be 1.0 to 60.0, 1.0 to 55.0, 3.0 to 50.0, 5.0 to 45.0, 8.0 to 40.0, 10.0 to 35.0, or 12.0 to 30.0. The fineness of the conductive yarn may be an average fineness, which may be an average value of five measurement points. The plied yarn described below may contain conductive yarns having a fineness in the above-mentioned range in at least one of the warp and weft. The fineness of the conductive yarn can be measured in accordance with JIS L 1013:2010.

[0034] The fineness (unit [tex]: hereinafter, the unit will be omitted in some cases) of the nonflammable yarn (nonflammable fiber) may be within the following ranges, from the viewpoint of easily achieving both excellent electromagnetic wave shielding properties and resin affinity. The fineness of the nonflammable yarn may be 10.0 or more, 20.0 or more, 30.0 or more, 40.0 or more, 45.0 or more, 50.0 or more, 55.0 or more, or 60.0 or more. The fineness of the nonflammable yarn may be 100.0 or less, 90.0 or less, 85.0 or less, 80.0 or less, 75.0 or less, or 70.0 or less. From these viewpoints, the fineness of the nonflammable yarn may be 10.0 to 100.0, 30.0 to 100.0, 40.0 to 100.0, 10.0 to 80.0, 30.0 to 80.0, 40.0 to 80.0, 10.0 to 70.0, 30.0 to 70.0, or 40.0 to 70.0. The fineness of the nonflammable yarn may be an average fineness, which may be an average value of five measurement points. The doubled and twisted yarn described below may contain a nonflammable yarn having a fineness in the above-mentioned range in at least one of the warp and weft. When the doubled and twisted yarn described below contains multiple nonflammable yarns, the total fineness (unit [tex]: hereinafter, the unit will be omitted in some cases) of the multiple nonflammable yarns may be in the following range. The total fineness of the non-flammable yarns may be 20.0 or more, 40.0 or more, 60.0 or more, 80.0 or more, 90.0 or more, 100.0 or more, 110.0 or more, or 120.0 or more. The total fineness of the non-flammable yarns may be 500.0 or less, 400.0 or less, 300.0 or less, 200.0 or less, 150.0 or less, or 140.0 or less. From these viewpoints, the total fineness of the non-flammable yarns may be 20.0 to 500.0, 40.0 to 400.0, 60.0 to 300.0, 80.0 to 300.0, 100.0 to 300.0, 100.0 to 200.0, 110.0 to 200.0, 110.0 to 150.0, or 120.0 to 140.0. The fineness of the non-flammable yarn can be measured in accordance with JIS R 3420:2013.

[0035] At least one of the warp and weft yarns may be a yarn bundle (doubled yarn) composed of multiple yarns, or may be a doubled yarn obtained by double-twisting multiple yarns. Examples of doubled yarns include doubled yarns obtained by double-twisting a conductive yarn and a non-flammable yarn together, doubled yarns obtained by double-twisting the same type of conductive yarn together, doubled yarns obtained by double-twisting multiple types of conductive yarns together, doubled yarns obtained by double-twisting the same type of non-flammable yarn together, and doubled yarns obtained by double-twisting multiple types of non-flammable yarns together. From the viewpoint of easily achieving both excellent electromagnetic shielding properties and resin affinity, at least one of the warp and weft yarns may be a doubled yarn obtained by double-twisting a conductive yarn and a non-flammable yarn together. From the viewpoint of easily achieving both excellent electromagnetic shielding properties and resin affinity, the woven fabric according to the present embodiment may be an embodiment in which the warp and weft yarns are doubled yarns obtained by double-twisting a conductive yarn and a non-flammable yarn together, and the conductive yarns adjacent to each other in the first direction and the conductive yarns adjacent to each other in the second direction are doubled yarns. The conductive yarn of a plied and twisted yarn obtained by plying and twisting a conductive yarn and a non-flammable yarn together has a front side portion located on the front side of the non-flammable yarn and a back side portion located on the back side of the non-flammable yarn. A plied and twisted yarn obtained by plied and twisting a conductive yarn and a non-flammable yarn together can be obtained, for example, by plied and twisting 1 to 3 conductive yarns and 1 to 6 non-flammable yarns using a known twisting machine. The fineness of the plied or twisted yarn can be measured in accordance with JIS R 3420:2013. In addition, the conductive yarn and the non-flammable yarn can be separated from the plied or twisted yarn using an untwisting machine or the like, and the fineness of each can be determined using the method described above.

[0036] The number of twists of the doubled and twisted yarn (unit: [turns / 25.4 mm]; hereinafter, the unit may be omitted in some cases) may be in the following ranges: From the viewpoint of easily obtaining excellent resin affinity, the number of twists of the doubled and twisted yarn may be 1.0 or more, 1.5 or more, 2.0 or more, 2.1 or more, 2.2 or more, 2.4 or more, 2.5 or more, 3.0 or more, 3.3 or more, 3.5 or more, 4.0 or more, 4.1 or more, 4.5 or more, 5.0 or more, or 5.1 or more. From the viewpoint of easily obtaining excellent electromagnetic wave shielding properties, the number of twists of the doubled and twisted yarn may be 20.0 or less, 15.0 or less, 10.0 or less, 9.0 or less, 8.0 or less, 7.0 or less, 6.5 or less, 6.0 or less, 5.5 or less, 5.1 or less, 5.0 or less, 4.6 or less, 4.5 or less, 4.1 or less, 4.0 or less, 3.5 or less, 3.3 or less, 3.0 or less, 2.5 or less, or 2.4 or less. From these viewpoints, the number of twists of the doubled and twisted yarn may be 1.0 to 20.0, 1.0 to 6.0, 1.0 to 4.5, 1.0 to 4.0, 1.0 to 3.0, 2.1 to 5.1, 2.2 to 4.6, 3.0 to 20.0, 3.0 to 6.0, 3.0 to 4.5, 3.0 to 4.0, 4.0 to 20.0, 4.0 to 6.0, 4.0 to 4.5, 4.5 to 20.0, or 4.5 to 6.0. The number of twists of the doubled and twisted yarn can be determined in accordance with JIS R 3912:2014 using a twist detector, by calculating from the number of turns required to untwist the test piece and the length of the test piece under standard tension before untwisting.

[0037] In at least one of the warp and weft yarns, the ratio M2 / M1 of the mass (fineness) M2 of the conductive yarn to the mass (fineness) M1 of the nonflammable yarn may be in the following range. From the viewpoint of easily obtaining excellent electromagnetic wave shielding properties, the ratio M2 / M1 may be 0.01 or more, 0.03 or more, 0.05 or more, 0.06 or more, 0.08 or more, or 0.10 or more. From the viewpoint of easily obtaining excellent resin affinity, the ratio M2 / M1 may be 0.24 or less, 0.20 or less, 0.18 or less, 0.15 or less, 0.12 or less, 0.11 or less, or 0.10 or less. From these viewpoints, the ratio M2 / M1 may be 0.01 to 0.24, 0.01 to 0.12, 0.01 to 0.11, 0.05 to 0.24, 0.05 to 0.12, 0.05 to 0.11, 0.06 to 0.24, 0.06 to 0.12, 0.06 to 0.11, or 0.06 to 0.10. When the warp or weft yarn is a doubled yarn or a doubled-twisted yarn, the mass M1 of the nonflammable yarn indicates the total mass (total fineness) of the nonflammable yarns constituting the doubled yarn or doubled-twisted yarn, and the mass M2 of the conductive yarn indicates the total mass (total fineness) of the conductive yarns constituting the doubled yarn or doubled-twisted yarn.

[0038] The weave density (unit [counts / 25.4 mm]: hereinafter, the unit may be omitted in some cases) of at least one of the warp and weft threads, from the viewpoint of easily achieving both excellent electromagnetic wave shielding properties and resin affinity, may be 15 to 100, 15 to 80, 15 to 40, 20 to 100, 20 to 80, 20 to 40, 25 to 100, 25 to 80, or 25 to 40. The weave density of the warp threads and weft threads can be measured using a fabric disassembly speculum in accordance with JIS R 3420:2013.

[0039] The weave of the woven fabric according to this embodiment is not particularly limited. Examples of weaves include plain weave, twill weave, satin weave, and rib weave. The weave may be a multiple weave such as a double weave (biaxial weave) or a triple weave. The weave may be a varied weave such as a basket weave or a rib weave. The weave may be a special weave such as a twill weave or a sand weave. The weave may be any other weave.

[0040] The adjacent warp yarns may be the same type of yarn, may be the same type of plied yarn, may be different types of yarn, or may be different types of plied yarn. The adjacent weft yarns may be the same type of yarn, may be the same type of plied yarn, may be different types of yarn, or may be different types of plied yarn. At least one of the warp yarns and the weft yarns may be composed of the same type of plied yarn including a conductive yarn. At least one of the warp yarns and the weft yarns may be composed of conductive yarns and non-flammable yarns arranged alternately, or may be composed of one type of conductive yarn and another type of conductive yarn arranged alternately, or may be composed of one type of plied yarn including a conductive yarn and another type of plied yarn including a conductive yarn arranged alternately. When at least one of the warp and weft threads is formed by alternately arranging conductive yarns and non-flammable yarns, the conductive yarn may be a single conductive yarn, a twisted yarn formed from a single conductive yarn, a doubled yarn formed from multiple conductive yarns, or a doubled / twisted yarn formed from multiple conductive yarns, and the non-flammable yarn may be a single non-flammable yarn, a twisted yarn formed from a single non-flammable yarn, a doubled yarn formed from multiple non-flammable yarns, or a doubled / twisted yarn formed from multiple non-flammable yarns. At least one of the warp and weft threads may include yarns that do not fall under the category of conductive yarns or non-flammable yarns.

[0041] The thickness of the woven fabric according to this embodiment may be within the following ranges. From the viewpoint of easily obtaining excellent mechanical strength or excellent electromagnetic shielding properties, the thickness of the woven fabric may be 100 μm or more, 150 μm or more, 200 μm or more, 250 μm or more, 280 μm or more, or 290 μm or more. The thickness of the woven fabric may be 500 μm or less, 450 μm or less, 400 μm or less, 350 μm or less, or 320 μm or less. From the viewpoint of easily obtaining excellent resin affinity, the thickness of the woven fabric may be 100 to 500 μm, 100 to 400 μm, 100 to 350 μm, 200 to 500 μm, 200 to 400 μm, 200 to 350 μm, 250 to 500 μm, 250 to 400 μm, or 250 to 350 μm. The thickness of the woven fabric may be an average thickness, which can be determined as the average value of measurements taken at 15 points in the woven fabric using a micrometer in accordance with JIS R 3420:2013.

[0042] The mass per unit area of ​​the woven fabric according to this embodiment (unit: g / m ２ ] (hereinafter, the unit indication may be omitted in some cases) may be in the following ranges. The mass per unit area may be 100 or more, 150 or more, 200 or more, 250 or more, 300 or more, or 350 or more. The mass per unit area may be 500 or less, 450 or less, 400 or less, 380 or less, or 350 or less. The mass per unit area may be 100 to 500, 100 to 400, 100 to 380, 200 to 500, 200 to 400, 200 to 380, 300 to 500, 300 to 400, or 300 to 380. The mass per unit area is measured by measuring the mass of three points of a woven fabric cut into a size of 200 mm x 200 mm using a scale conforming to JIS R 3420:2013, and dividing each of the three points by 1 m ２ It can be calculated as the average value converted into mass per unit.

[0043] In the woven fabric according to the present embodiment, a plurality of enclosed regions are formed, each surrounded by conductive yarns adjacent to each other in a first direction and conductive yarns adjacent to each other in a second direction intersecting (for example, perpendicular to) the first direction. The enclosed regions may have a portion where at least one of the warp yarns and the weft yarns is exposed, or may have a portion where an opening is formed without the presence of the warp yarns and the weft yarns.

[0044] When at least one of the warp and weft yarns is a plied yarn obtained by plying and twisting a conductive yarn and a non-flammable yarn together, the enclosed area on the front side (front surface side and one surface side) of the woven fabric according to this embodiment is defined by a front-side position portion of the conductive yarn on at least one of the four sides of the enclosed area. The front-side position portion of the conductive warp yarn that defines the enclosed area may be covered by a weft yarn, and the front-side position portion of the conductive weft yarn that defines the enclosed area may be covered by a warp yarn. Similarly, when at least one of the warp and weft yarns is a plied yarn obtained by plied and twisting a conductive yarn and a non-flammable yarn together, the enclosed area on the back side (back surface side and other surface side) of the woven fabric according to this embodiment is defined by a back-side position portion of the conductive yarn on at least one of the four sides of the enclosed area. The back side position portion of the warp conductive yarn that defines the surrounding area may be covered with the weft yarn, and the back side position portion of the weft conductive yarn that defines the surrounding area may be covered with the warp yarn.

[0045] The average area of ​​the enclosed region when the woven fabric according to this embodiment is viewed from a third direction perpendicular to both the first direction and the second direction is 0.075 to 2.000 mm ２ The average area of ​​the surrounding region is 0.075 mm from the viewpoint of obtaining excellent resin affinity. ２ The average area of ​​the surrounding region is set to 2,000 mm from the viewpoint of obtaining excellent electromagnetic wave shielding properties. ２ The following is the result.

[0046] Average area of ​​the enclosed region (unit: mm ２] (hereinafter, the unit indication may be omitted in some cases) may be in the following range from the viewpoint of easily achieving both excellent electromagnetic wave shielding properties and resin affinity. The average area of ​​the surrounding region is 0.080 or more, 0.090 or more, 0.100 or more, 0.110 or more, 0.120 or more, 0.130 or more, 0.140 or more, 0.150 or more, 0.160 or more, 0.170 or more, 0.180 or more, 0.190 or more, 0.200 or more, 0.210 or more, 0.220 or more, 0.230 or more, 0.240 or more, 0.250 or more, 0.260 or more, 0.270 or more, 0.280 or more, 0.290 or more, 0.300 or more, 0.305 or more, 0.306 or more, 0.307 or more, 0.308 or more, 0.309 or more, 0.310 or more, 0.315 or more, 0.320 or more, 0.3 0.25 or more, 0.330 or more, 0.335 or more, 0.340 or more, 0.345 or more, 0.350 or more, 0.355 or more, 0.358 or more, 0.360 or more, 0.370 or more, 0.380 or more, 0.390 or more, 0.400 or more, 0.410 or more, 0.420 or more, 0.430 or more, 0.440 or more, 0.450 or more, 0.460 or more, 0.470 or more, 0.475 or more, 0.480 or more, 0.485 or more, 0.490 or more, 0.495 or more, 0.500 or more, 0.505 or more, 0.510 or more, 0.515 or more, 0.520 or more, 0.525 or more, or 0.530 or more.The average area of ​​the surrounding region is 1.900 or less, 1.800 or less, 1.700 or less, 1.600 or less, 1.500 or less, 1.400 or less, 1.300 or less, 1.200 or less, 1.100 or less, 1.000 or less, 0.900 or less, 0.800 or less, 0.700 or less, 0.650 or less, 0.600 or less, 0.590 or less, 0.580 or less, 0.570 or less, 0.565 or less, 0.560 or less, 0.555 or less, 0.550 or less, 0.545 or less, 0.540 or less, 0.535 or less, 0.532 or less, 0.530 or less, 0.5 0.25 or less, 0.520 or less, 0.515 or less, 0.510 or less, 0.505 or less, 0.500 or less, 0.495 or less, 0.490 or less, 0.485 or less, 0.480 or less, 0.475 or less, 0.470 or less, 0.460 or less, 0.450 or less, 0.440 or less, 0.430 or less, 0.420 or less, 0.410 or less, 0.400 or less, 0.390 or less, 0.380 or less, 0.370 or less, 0.360 or less, 0.350 or less, 0.340 or less, 0.330 or less, 0.320 or less, or 0.310 or less. In view of the above, the average area of ​​the surrounding region may be 0.075 to 1.000, 0.075 to 0.535, 0.075 to 0.532, 0.075 to 0.470, 0.075 to 0.400, 0.309 to 2.000, 0.309 to 0.535, 0.309 to 0.532, 0.309 to 0.470, 0.309 to 0.400, 0.358 to 2.000, 0.358 to 0.535, 0.358 to 0.532, 0.358 to 0.470, 0.500 to 2.000, 0.500 to 0.535, 0.500 to 0.532, 0.532 to 2.000, or 0.532 to 0.535. When the average area of ​​the surrounding region is 0.309 to 0.532, the average values ​​of the electromagnetic shielding properties in the warp and weft directions are, for example, 45.5 dB or more at 100 kHz, 45.5 dB or more at 100 MHz, 38.0 dB or more at 1 GHz, and 30.0 dB or more at 15 GHz. When the average area of ​​the surrounding region is 0.358 to 0.470, the average values ​​of the electromagnetic shielding properties in the warp and weft directions are, for example, 39.0 dB or more at 1 GHz and 31.0 dB or more at 15 GHz.

[0047] The average area of ​​the enclosed region is the average value of the area of ​​the enclosed region on the front side of the woven fabric according to this embodiment and the area of ​​the enclosed region on the back side of the woven fabric according to this embodiment. If the total number of enclosed regions on the front and back sides of the woven fabric is 200 or more, the average area of ​​the enclosed region is the average value of the areas of 100 enclosed regions on the front side and 100 enclosed regions on the back side. If the total number of enclosed regions on the front and back sides of the woven fabric is less than 200, the average area of ​​the enclosed region is the average value of the areas of all enclosed regions on the front and back sides. A method for deriving the average area of ​​the enclosed region will be described later using drawings.

[0048] The coefficient of variation of the area of ​​the surrounding region may be in the following ranges: from the viewpoint of easily ensuring excellent electromagnetic shielding properties over a wide range of frequencies, the coefficient of variation may be 20.0% or more, 25.0% or more, 30.0% or more, 32.0% or more, 34.0% or more, 36.0% or more, 38.0% or more, 40.0% or more, 42.0% or more, 43.0% or more, 44.0% or more, 45.0% or more, 46.0% or more, 47.0% or more, 48.0% or more, 49.0% or more, 50.0% or more, 51.0% or more, 52.0% or more, 53.0% or more, or 54.0% or more. When the coefficient of variation is 42.0% or more, the average values ​​of the electromagnetic shielding properties in the warp and weft directions are, for example, 45.0 dB or more at 100 kHz, 45.0 dB or more at 100 MHz, 37.0 dB or more at 1 GHz, and 28.5 dB or more at 15 GHz. When the coefficient of variation is 50.0% or more, the average values ​​of the electromagnetic shielding properties in the warp and weft directions are, for example, 45.5 dB or more at 100 kHz, 45.5 dB or more at 100 MHz, 38.0 dB or more at 1 GHz, and 30.0 dB or more at 15 GHz. From the viewpoint of easily ensuring excellent resin affinity throughout the entire woven fabric, the coefficient of variation is set to 80.0% or less, 78.0% or less, 76.0% or less, 74.0% or less, 72.0% or less, 70.0% or less, 69.0% or less, 68.0% or less, 67.0% or less, 66.0% or less, 65.0% or less, 64.0% or less, 63.0% or less, 62.0% or less, 61.0% or less, 60. It may be 0% or less, 58.0% or less, 56.0% or less, 55.0% or less, 54.0% or less, 53.0% or less, 52.0% or less, 51.0% or less, 50.0% or less, 49.0% or less, 48.0% or less, 47.0% or less, 46.0% or less, 45.0% or less, 44.0% or less, 43.0% or less, 42.0% or less, 40.0% or less, or 38.0% or less. From these viewpoints, the coefficient of variation may be 20.0 to 80.0%, 20.0 to 63.0%, 20.0 to 60.0%, 20.0 to 50.0%, 20.0 to 42.0%, 42.0 to 80.0%, 42.0 to 63.0%, 42.0 to 60.0%, 42.0 to 50.0%, 50.0 to 80.0%, 50.0 to 63.0%, or 50.0 to 60.0%.The coefficient of variation of the area of ​​the enclosed region is the ratio of the standard deviation of the group of areas giving the above-mentioned average area to the above-mentioned average area (standard deviation of the group of areas / average area).

[0049] Examples of electromagnetic shielding fabrics will now be described with reference to the drawings. FIG. 1 is a plan view showing a portion of the configuration of one example of an electromagnetic shielding fabric. FIG. 2 is a plan view showing a portion of ply-twisted yarns forming the warp and weft yarns of the electromagnetic shielding fabric of FIG. 1. FIG. 3 is a view of a portion of a surrounding region formed on the front side of the electromagnetic shielding fabric of FIG. 1, viewed from above in the Z-axis direction. FIG. 4 is a view of a portion of a surrounding region formed on the back side of the electromagnetic shielding fabric of FIG. 1, viewed from above in the Z-axis direction. FIGS. 3 and 4 illustrate different portions of the electromagnetic shielding fabric of FIG. 1. FIG. 5 is a plan view showing a portion of the configuration of another example of an electromagnetic shielding fabric. In the description of the drawings, identical elements are designated by the same reference numerals, and redundant description will be omitted. For ease of description, mutually orthogonal X-, Y-, and Z-axes are set in FIGS. 1 to 5. The dimensional proportions in the drawings do not necessarily correspond to those in the description.

[0050] In the electromagnetic shielding fabric 1 shown in Fig. 1, warp yarns 3 and weft yarns 5 are woven in a plain weave. Fig. 1 shows a portion of the electromagnetic shielding fabric 1 laid flat on the XY plane so that the warp yarns 3 extend in the Y-axis direction (first direction) and the weft yarns 5 extend in the X-axis direction (second direction). The warp yarns 3 are formed from conductive yarns 71 and non-flammable yarns 73, and extend in the Y-axis direction while being arranged in multiple numbers in the X-axis direction. The weft yarns 5 are formed from conductive yarns 71 and non-flammable yarns 73, and extend in the X-axis direction while being arranged in multiple numbers in the Y-axis direction.

[0051] Each of the multiple warp threads 3 is formed from a doubled / twisted yarn 7 obtained by twisting together a conductive thread 71 and a non-flammable thread 73. For example, each of the multiple warp threads 3 is formed from a doubled / twisted yarn 7 obtained by twisting together one conductive thread 71 and two non-flammable threads 73, 73. The doubled / twisted yarn 7 shown in FIG. 2 is an example in which the twist direction is right-handed (S twist), but it may also be left-handed (Z twist). Like each of the multiple warp threads 3, each of the multiple weft threads 5 is formed from a doubled / twisted yarn 7 obtained by twisting together a conductive thread 71 and a non-flammable thread 73.

[0052] 3, the electromagnetic shielding fabric 1 has a plurality of surrounding areas A formed therein, each surrounded by conductive yarns 71, 71 adjacent to each other in the Y-axis direction and conductive yarns 71, 71 adjacent to each other in the X-axis direction. More specifically, the electromagnetic shielding fabric 1 has a plurality of surrounding areas A formed therein, each surrounded by conductive yarns 71, 71 of doubled and twisted yarns 7, 7 included in warp yarns 3, 3 adjacent to each other in the X-axis direction and conductive yarns 71, 71 of doubled and twisted yarns 7, 7 included in weft yarns 5, 5 adjacent to each other in the Y-axis direction.

[0053] 2, the doubled / twisted yarn 7, which is made by plying and twisting one conductive yarn 71 and two non-combustible yarns 73, 73, has the conductive yarn 71 and the non-combustible yarns 73, 73 spirally wound around each other. Therefore, when the doubled / twisted yarn 7 laid flat on the XY plane and viewed from above in the Z-axis direction, there are portions where the conductive yarn 71 is located on the front side of the non-combustible yarn 73 and portions where the conductive yarn 71 is located on the back side of the non-combustible yarn 73 (portions where the conductive yarn 71 is hidden by the non-combustible yarn 73 and is not visible: portions where the conductive yarn 71 is visible from below in the Z-axis direction, opposite to above in the Z-axis direction). Thus, when the doubled / twisted yarn 7 is viewed from above in the Z-axis direction, the portion where the conductive yarn 71 is located on the front side of the non-combustible yarn 73 is referred to as the "front side position portion FS," and the portion where the conductive yarn 71 is located on the back side of the non-combustible yarn 73 is referred to as the "back side position portion BS." The surrounding area A formed on the front side of the electromagnetic shielding fabric 1 (the surrounding area A when viewed from above in the Z-axis direction) is an area surrounded by the front-side position portions FS of the conductive yarns 71, 71 adjacent to each other in the Y-axis direction and the front-side position portions FS of the conductive yarns 71, 71 adjacent to each other in the X-axis direction. The surrounding area A formed on the back side of the electromagnetic shielding fabric 1 (the surrounding area A when viewed from below in the Z-axis direction) is an area surrounded by the back-side position portions BS of the conductive yarns 71, 71 adjacent to each other in the Y-axis direction and the back-side position portions BS of the conductive yarns 71, 71 adjacent to each other in the X-axis direction.

[0054] When the electromagnetic shielding fabric 1, which includes warp yarns 3 and weft yarns 5 formed from such a double-twisted yarn 7, is laid flat on the XY plane and viewed from above in the Z-axis direction, as shown in FIG. 3 , there are portions of the conductive yarns 71 on the front side of the electromagnetic shielding fabric 1 where the conductive yarns 71 are located on the front side of the non-flammable yarns 73, and portions where the conductive yarns 71 are located on the back side of the non-flammable yarns 73. The portion where the conductive thread 71 is located on the front side of the non-flammable thread 73 includes an overlapping portion where the conductive thread 71 overlaps with the weft thread 5 and the front side position portion FS of the warp thread 3 is not exposed (the portion between the colored portions in the conductive thread 71 in Figure 3), an overlapping portion where the conductive thread 71 overlaps with the warp thread 3 and the front side position portion FS of the weft thread 5 is not exposed (the portion between the colored portions in the conductive thread 71 in Figure 3), an exposed portion where the front side position portion FS of the warp thread 3 is exposed without overlapping with the weft thread 5 (the colored portion in the conductive thread 71 in Figure 3), and an exposed portion where the front side position portion FS of the weft thread 5 is exposed without overlapping with the warp thread 3 (the colored portion in the conductive thread 71 in Figure 3). In Figure 3, the portion where the conductive thread 71 is located on the back side of the non-flammable thread 73 is indicated by a dashed dotted line area.

[0055] Similarly, when the electromagnetic shielding fabric 1, which includes warp yarns 3 and weft yarns 5 formed from the doubled-and-twisted yarn 7, is laid flat on the XY plane and viewed from below in the Z-axis direction, there are portions of the conductive yarn 71 on the back side of the electromagnetic shielding fabric 1 where the conductive yarn 71 is located behind the noncombustible yarn 73 and portions where the conductive yarn 71 is located on the front side of the noncombustible yarn 73. The portions where the conductive yarn 71 is located behind the noncombustible yarn 73 (the dashed-dotted line areas shown in FIG. 4 ) have an overlapping portion where the back side portion BS of the warp yarn 3 overlaps with the weft yarn 5 and is not exposed, an overlapping portion where the back side portion BS of the weft yarn 5 overlaps with the warp yarn 3 and is not exposed, an exposed portion where the back side portion BS of the warp yarn 3 is exposed without overlapping with the weft yarn 5, and an exposed portion where the back side portion BS of the weft yarn 5 is exposed without overlapping with the warp yarn 3.

[0056] In the electromagnetic wave shielding fabric 1, the position, size, shape, etc. of the surrounded regions A differ from each other on the front side and back side of the electromagnetic wave shielding fabric 1. In Fig. 3, the surrounded regions A are surrounded by front side non-intersecting portions FP where the conductive yarns 71 are located on the front side with respect to the non-flammable yarns 73 and do not intersect with the warp yarns 3 and weft yarns 5, and seven surrounded regions A are shown. In Fig. 4, the surrounded regions A are surrounded by back side non-intersecting portions BP where the conductive yarns 71 are located on the back side with respect to the non-flammable yarns 73 and do not intersect with the warp yarns 3 and weft yarns 5, and three surrounded regions A are shown.

[0057] The enclosed area A on the front side of the electromagnetic wave shielding fabric 1 is an area defined by the front side position portions FS of the conductive threads 71, 71 adjacent to each other in the X-axis direction and the front side position portions FS of the conductive threads 71, 71 adjacent to each other in the Y-axis direction (an area whose four sides are formed by the front side position portions FS (front side non-intersecting portions FP)). On the front side of the electromagnetic wave shielding fabric 1, the area that is not defined by the front side position portions FS of the conductive yarns 71, 71 adjacent to each other in the X-axis direction (the area where one or two sides extending in the Y-axis direction are not defined by the front side position portions FS of the conductive yarns 71, 71 adjacent to each other in the X-axis direction) and the area that is not defined by the front side position portions FS of the conductive yarns 71, 71 adjacent to each other in the Y-axis direction (the area where one or two sides extending in the X-axis direction are not defined by the front side position portions FS of the conductive yarns 71, 71 adjacent to each other in the Y-axis direction) do not fall under the enclosed area A.

[0058] Similarly, the enclosed area A on the back side of the electromagnetic wave shielding fabric 1 is an area defined by the back side position portions BS of the conductive threads 71, 71 adjacent to each other in the X-axis direction and the back side position portions BS of the conductive threads 71, 71 adjacent to each other in the Y-axis direction (an area whose four sides are formed by the back side position portions BS (back side non-intersecting portions BP)). On the back side of the electromagnetic wave shielding fabric 1, the area that is not defined by the respective back position portions BS of the conductive threads 71, 71 that are adjacent to each other in the X-axis direction (the area where one or two sides extending in the Y-axis direction are not defined by the respective back position portions BS of the conductive threads 71, 71 that are adjacent to each other in the X-axis direction) and the area that is not defined by the respective back position portions BS of the conductive threads 71, 71 that are adjacent to each other in the Y-axis direction (the area where one or two sides extending in the X-axis direction are not defined by the back position portions BS of the conductive threads 71, 71 that are adjacent to each other in the Y-axis direction) do not fall under the enclosed area A.

[0059] The area of ​​one surrounding region A in the electromagnetic shielding fabric 1 can be calculated, for example, as the product of the X-direction distance between adjacent conductive yarns 71, 71 in the X-axis direction and the Y-direction distance between adjacent conductive yarns 71, 71 in the Y-axis direction. If the shape of the surrounding region A is not rectangular or square, the shortest distance between adjacent conductive yarns is used as the X-direction distance and the Y-direction distance. The area of ​​the surrounding region A may be calculated using a known area calculation method based on the lengths of the four sides forming the surrounding region A. The X-direction distance and the Y-direction distance can be measured by observing the electromagnetic shielding fabric 1 from the front or back side using a microscope (e.g., VHX-600, manufactured by Keyence Corporation). Alternatively, the area of ​​the surrounding region A may be measured (calculated) using area calculation software built into the microscope.

[0060] When calculating the product of the X-direction distance and the Y-direction distance, for example, the area of ​​the enclosed region A on the front side of the electromagnetic shielding fabric 1 shown in FIG. 3 can be calculated as the product of the X-direction distance (Xsa, Xsb, Xsc, Xsd, etc.) between adjacent conductive threads 71, 71 in the X-axis direction and the Y-direction distance (Ysa, Ysb, etc.) between adjacent conductive threads 71, 71 in the Y-axis direction. That is, the area of ​​the surrounding region A1 on the front side of the electromagnetic shielding fabric 1 is obtained as the product of the X-direction distance Xsa and the Y-direction distance Ysa, the area of ​​the surrounding region A2 is obtained as the product of the X-direction distance Xsb and the Y-direction distance Ysa, the area of ​​the surrounding region A3 is obtained as the product of the X-direction distance Xsb and the Y-direction distance Ysb, the area of ​​the surrounding region A4 is obtained as the product of the X-direction distance Xsc and the Y-direction distance Ysa, the area of ​​the surrounding region A5 is obtained as the product of the X-direction distance Xsc and the Y-direction distance Ysb, the area of ​​the surrounding region A6 is obtained as the product of the X-direction distance Xsd and the Y-direction distance Ysa, and the area of ​​the surrounding region A7 is obtained as the product of the X-direction distance Xsd and the Y-direction distance Ysb. Similarly, for example, the area of ​​the surrounding area A11 on the back side of the electromagnetic shielding fabric 1 as shown in FIG. 4 is obtained as the product of the X-direction distance Xba and the Y-direction distance Yba, the area of ​​the surrounding area A12 is obtained as the product of the X-direction distance Xba and the Y-direction distance Ybb, and the area of ​​the surrounding area A13 is obtained as the product of the X-direction distance Xba and the Y-direction distance Ybc.

[0061] The average area of ​​the surrounded region A when the electromagnetic shielding fabric 1 is viewed from the Z-axis direction is the average value of the area of ​​the surrounded region A on the front side of the electromagnetic shielding fabric 1 and the area of ​​the surrounded region A on the back side of the electromagnetic shielding fabric 1. If the total number of surrounded regions A on the front and back sides of the electromagnetic shielding fabric 1 is 200 or more, the average area of ​​the surrounded region A is the average value of the areas of 100 surrounded regions A on the front side and 100 surrounded regions A on the back side. If the total number of surrounded regions A on the front and back sides of the electromagnetic shielding fabric 1 is less than 200, the average area of ​​the surrounded region A is the average value of the areas of all the surrounded regions A on the front and back sides. When the total number of enclosed areas A on the front and back sides of the electromagnetic wave shielding fabric 1 is 200 or more, the enclosed area A used to calculate the average area is preferentially selected from the enclosed area A in the center of the electromagnetic wave shielding fabric 1, and the enclosed areas A can be selected in order from the center toward the periphery.

[0062] The area of ​​the enclosed region A can be calculated not only by the method of individually calculating each actually existing enclosed region A as described above, but also by measuring the X-direction distances (Xsa, Xsb, Xsc, Xsd, etc.) between adjacent conductive yarns 71, 71 in the X-axis direction at multiple locations (e.g., 10 locations) on each of the front and back sides of the electromagnetic shielding fabric 1, and measuring the Y-direction distances (Ysa, Ysb, etc.) between adjacent conductive yarns 71, 71 in the Y-axis direction at multiple locations (e.g., 10 locations), and calculating the products of each combination of these X-direction distances and Y-direction distances (e.g., 100 combinations = 10 locations x 10 locations). In this case, the average of the sums of the products calculated for the front and back sides of the electromagnetic shielding fabric 1 (e.g., the sum of 100 products on the front side and the sum of 100 products on the back side) can be used as the average area of ​​the enclosed region A.

[0063] Although an example of an electromagnetic wave shielding fabric has been described above, the configuration of the electromagnetic wave shielding fabric is not limited to the above configuration, and various modifications are possible within the scope of the invention.

[0064] The electromagnetic wave shielding fabric 1 described above is composed of warp threads 3 and weft threads 5 made of a double-twisted yarn 7 formed from one conductive thread 71 and two non-flammable threads 73, but the configuration of the electromagnetic wave shielding fabric is not limited to this configuration.

[0065] For example, an electromagnetic wave shielding fabric may include a warp thread group in which warp threads (hereinafter sometimes referred to as "conductive warp threads") made of one conductive yarn, a twisted yarn made of one conductive yarn, a doubled yarn made of multiple conductive yarns, or a doubled-and-twisted yarn made of multiple conductive yarns, and warp threads (hereinafter sometimes referred to as "non-flammable warp threads") made of one non-flammable yarn, a twisted yarn made of one non-flammable yarn, a doubled yarn made of multiple non-flammable yarns, or a doubled-and-twisted yarn made of multiple non-flammable yarns are alternately arranged in the X-axis direction; The fabric may be composed of a warp thread (hereinafter sometimes referred to as a "conductive weft thread") consisting of a single conductive yarn, a twisted yarn formed from a single conductive yarn, a doubled yarn formed from multiple conductive yarns, or a doubled-and-twisted yarn formed from multiple conductive yarns, and a weft thread (hereinafter sometimes referred to as a "non-flammable weft thread") consisting of a single non-flammable yarn, a twisted yarn formed from a single non-flammable yarn, a doubled yarn formed from multiple non-flammable yarns, or a doubled-and-twisted yarn formed from multiple non-flammable yarns, arranged alternately in the Y-axis direction.

[0066] 5 , a plurality of enclosed areas A are formed on the front and back sides of an electromagnetic shielding fabric configured in this manner (hereinafter also referred to as an "alternately arranged electromagnetic shielding fabric"), each surrounded by conductive warp threads 3, 3 adjacent to each other in the X-axis direction (second direction) and conductive weft threads 5, 5 adjacent to each other in the Y-axis direction (first direction). In the alternately arranged electromagnetic shielding fabric, conductive warp threads 3, 3 adjacent to each other in the X-axis direction are arranged with one non-flammable warp thread 3 therebetween, and conductive weft threads 5, 5 adjacent to each other in the Y-axis direction are arranged with one non-flammable weft thread 5 therebetween. Therefore, a non-flammable warp thread 3 and a non-flammable weft thread 5 are arranged in each of the plurality of enclosed areas A.

[0067] The conductive warp yarns 3 and conductive weft yarns 5 that make up the alternately arranged electromagnetic shielding fabric do not contain any non-flammable yarns, and therefore, unlike the plied yarns 7 of the electromagnetic shielding fabric 1 shown in Fig. 2, there are no portions where the conductive yarns 71 are hidden by the non-flammable yarns 73 when the electromagnetic shielding fabric is viewed from the Z-axis direction. In such an alternately arranged electromagnetic shielding fabric, there is no difference in the appearance of the conductive yarns 71 when viewed from above in the Z-axis direction and when viewed from below in the Z-axis direction. In other words, in such an alternately arranged electromagnetic shielding fabric, the position, size, shape, etc. of the enclosed area A are substantially identical on the front and back sides of the electromagnetic shielding fabric.

[0068] In the electromagnetic shielding fabric 1 described above, the plied yarns 7 forming the warp yarns 3 and the weft yarns 5 include one conductive yarn 71, but the configuration of the electromagnetic shielding fabric is not limited to this configuration. For example, the plied yarns 7 forming the warp yarns 3 and the weft yarns 5 may include a plurality of conductive yarns 71.

[0069] When the doubled and twisted yarn 7 of the warp thread 3 includes a plurality of conductive threads 71, the conductive threads 71, 71 adjacent to each other in the X-axis direction (second direction) refer to the conductive thread 71 included in one of the adjacent warp threads 3, 3, and the conductive thread 71 included in the other of the adjacent warp threads 3, 3. Furthermore, when the doubled and twisted yarn 7 in each of one warp thread 3 and the other warp thread 3 includes a plurality of conductive threads 71, the adjacent conductive threads 71, 71 refer to a combination of conductive threads 71, 71 in which one of the plurality of conductive threads 71 ​​included in one warp thread 3 and one of the plurality of conductive threads 71 ​​included in the other warp thread 3 are at the shortest distance in the X-axis direction (second direction).

[0070] Similarly, when the doubled and twisted yarn 7 of the weft yarn 5 includes multiple conductive threads 71, the conductive threads 71, 71 adjacent to each other in the Y-axis direction (first direction) refer to the conductive thread 71 included in one of the adjacent weft yarns 5, 5, and the conductive thread 71 included in the other of the adjacent weft yarns 5, 5. Furthermore, when the doubled and twisted yarn 7 in each of one weft yarn 5 and the other weft yarn 5 includes multiple conductive threads 71, the adjacent conductive threads 71, 71 refer to a combination of conductive threads 71, 71 in which one of the multiple conductive threads 71 ​​included in one weft yarn 5 and one of the multiple conductive threads 71 ​​included in the other weft yarn 5 are at the shortest distance in the Y-axis direction (first direction).

[0071] EXAMPLES The present invention will be explained in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[0072] <Preparation of Evaluation Fabrics> (Example 1) One conductive yarn (silver-plated nylon yarn, AGposs (registered trademark), manufactured by Mitsufuji Corporation, average fineness 15.0 tex, hereinafter referred to as "AgPA") and two non-flammable yarns (E-glass fiber yarn, ECDE75-1 / 0 1.0Z, manufactured by Nitto Boseki Co., Ltd., average fineness 67.5 tex, hereinafter referred to as "GF") were ply-twisted using a twisting machine to obtain ply-twisted yarn 1, which was twisted 2.4 times / 25.4 mm. The mass ratio of the conductive yarn to the non-flammable yarn (ratio "conductive yarn / non-flammable yarn": the same applies hereinafter) was 0.11.

[0073] Using this plied yarn 1 as the warp and weft, a plain weave was performed with a warp density of 28 / 25.4 mm and a weft density of 28 / 25.4 mm to obtain a woven fabric for evaluation. The woven fabric for evaluation had an average thickness of 295 μm and a mass per unit area of ​​350 g / m ２ and the average area of ​​the surrounding region is 0.310 mm ２ The coefficient of variation of the area of ​​the surrounded region was 54.4%.

[0074] Example 2 One AgPA strand and two GF strands were ply-twisted using a twisting machine to obtain ply-twisted yarn 2 having a twist of 3.3 turns / 25.4 mm. The mass ratio of the conductive yarn to the non-flammable yarn was 0.11.

[0075] Using this plied yarn 2 as the warp and weft, a plain weave was performed with a warp density of 28 / 25.4 mm and a weft density of 28 / 25.4 mm to obtain a woven fabric for evaluation. The woven fabric for evaluation had an average thickness of 308 μm and a mass per unit area of ​​343 g / m ２ and the average area of ​​the surrounding region is 0.405 mm ２ The coefficient of variation of the area of ​​the surrounded region was 50.3%.

[0076] Example 3: One AgPA strand and two GF strands were twisted together using a twisting machine to obtain plied and twisted yarn 3-1 with a twist of 2.4 turns / 25.4 mm. Furthermore, one AgPA strand and two GF strands were twisted together using a twisting machine to obtain plied and twisted yarn 3-2 with a twist of 4.1 turns / 25.4 mm. The mass ratio of conductive yarn to non-flammable yarn in plied and twisted yarn 3-1 and plied and twisted yarn 3-2 was 0.11.

[0077] Using the above-mentioned plied yarn 3-1 as the warp yarn and the above-mentioned plied yarn 3-2 as the weft yarn, a plain weave was performed with a warp density of 28 / 25.4 mm and a weft density of 28 / 25.4 mm to obtain a woven fabric for evaluation. The woven fabric for evaluation had an average thickness of 307 μm and a mass per unit area of ​​355 g / m ２ and the average area of ​​the surrounding region is 0.531 mm ２ The coefficient of variation of the area of ​​the surrounded region was 51.5%.

[0078] Example 4 One AgPA strand and two GF strands were ply-twisted using a twisting machine to obtain ply-twisted yarn 4 having a twist of 4.1 turns / 25.4 mm. The mass ratio of the conductive yarn to the non-flammable yarn was 0.11.

[0079] Using this plied yarn 4 as the warp and weft, a plain weave was performed with a warp density of 28 / 25.4 mm and a weft density of 28 / 25.4 mm to obtain a woven fabric for evaluation. The woven fabric for evaluation had an average thickness of 307 μm and a mass per unit area of ​​358 g / m ２ and the average area of ​​the surrounding region is 0.535 mm ２ The coefficient of variation of the area of ​​the surrounded region was 47.7%.

[0080] Example 5: One AgPA strand and two GF strands were twisted together using a twisting machine to obtain plied and twisted yarn 5-1 with a twist of 5.1 turns / 25.4 mm. Furthermore, one AgPA strand and two GF strands were twisted together using a twisting machine to obtain plied and twisted yarn 5-2 with a twist of 2.4 turns / 25.4 mm. The mass ratio of conductive yarn to non-flammable yarn in plied and twisted yarn 5-1 and plied and twisted yarn 5-2 was 0.11.

[0081] Using the above-mentioned plied yarn 5-1 as the warp yarn and the above-mentioned plied yarn 5-2 as the weft yarn, a plain weave was performed with a warp density of 28 / 25.4 mm and a weft density of 28 / 25.4 mm to obtain a woven fabric for evaluation. The woven fabric for evaluation had an average thickness of 303 μm and a mass per unit area of ​​358 g / m ２ and the average area of ​​the surrounding region is 0.534 mm ２ The coefficient of variation of the area of ​​the surrounded region was 36.2%.

[0082] Comparative Example 1: AgPA and GF were alternately arranged in the warp and AgPA and GF were alternately arranged in the weft, and a plain weave was performed with a warp density of 28 / 25.4 mm and a weft density of 28 / 25.4 mm to obtain a fabric for evaluation. The mass ratio of the conductive yarn to the non-flammable yarn was 0.10. The average thickness of the fabric for evaluation was 300 μm, and the mass per unit area was 250 g / m. ２ and the average area of ​​the surrounding area is 2.431 mm ２ It was.

[0083] Comparative Example 2 Two strands of AgPA and one strand of GF were ply-twisted using a twisting machine to obtain ply-twisted yarn X with a twist of 3.3 turns / 25.4 mm. The mass ratio of the conductive yarn to the non-flammable yarn was 0.25.

[0084] This plied yarn X was used as the warp and weft to form a plain weave with a warp density of 28 / 25.4 mm and a weft density of 28 / 25.4 mm, to obtain a woven fabric for evaluation. The woven fabric for evaluation had an average thickness of 324 μm and a mass per unit area of ​​370 g / m ２ and the average area of ​​the surrounding region is 0.070 mm ２ It was.

[0085] <Measurement of the Area of ​​the Surrounded Region> The average area of ​​the above-mentioned surrounded region (the region surrounded by the conductive yarn) was obtained using the method described above with reference to the drawings. On each of the front and back sides of the evaluation fabric, the X-direction distance between adjacent conductive yarns in the X-axis direction (the direction of the warp yarns) was measured at 10 locations, and the Y-direction distance between adjacent conductive yarns in the Y-axis direction (the direction of the weft yarns) was measured at 10 locations. The product of each combination of these X-direction distances and Y-direction distances (100 combinations) was calculated. The average value of the sum of the products calculated for the front and back sides of the evaluation fabric (the sum of the 100 products on the front side and the 100 products on the back side) was used as the average area of ​​the surrounded region. The coefficient of variation of the area of ​​the above-mentioned surrounded region was obtained as the "standard deviation of the area group used to calculate the average area / average area."

[0086] <Measurement of Electromagnetic Wave Shielding Property> The electromagnetic wave shielding properties (unit: dB) of the above-described evaluation fabrics were measured in the warp direction and weft direction. The electromagnetic wave shielding properties in the frequency range of 100 kHz to less than 1 GHz (Examples 1 to 5 and Comparative Examples 1 and 2) were measured by the KEC method using a spectrum analyzer (Keysight Technologies, N9000A, equipped with a signal generator) and a measuring jig (Anritsu Corporation, MA86C2B). The electromagnetic wave shielding properties in the frequency range of 1 to 15 GHz (Examples 1 to 5 and Comparative Examples 1 and 2) were measured by the DFFC method using a vector network analyzer (Keysight Technologies, N5222A) and a measuring jig (Sanken Electric Co., Ltd., DFFC-18). The electromagnetic wave shielding properties at 40 GHz and 110 GHz (Examples 1 and 5) were measured by the free space method using the following equipment. (Free space method measuring equipment) [Vector network analyzer] MS4647B (VNA main unit) 1 unit (Anritsu Corporation) 3739B (millimeter wave test head) 1 unit (Anritsu Corporation) 3743A (millimeter wave module) 2 units (Anritsu Corporation) [Free space method device] BD1-26.5A (device main unit) 1 unit (Keycom Corporation) [Antenna group (2 units each)] RH42S (18-26.5 GHz) (Keycom Corporation) RH28S (26.5-40 GHz) (Keycom Corporation) RH19R (40-60 GHz) (Keycom Corporation) RH12R (60-90 GHz) (Keycom Corporation) RH10R (75-110 GHz) (Keycom Corporation)

[0087] The electromagnetic shielding property in the warp direction, the electromagnetic shielding property in the weft direction, the average value A of the electromagnetic shielding property in the warp direction and the electromagnetic shielding property in the weft direction, and the ratio of the difference in the electromagnetic shielding property in the warp direction and the weft direction to the average value A of the electromagnetic shielding property ([(difference in electromagnetic shielding property in the warp direction and the weft direction) / (average value A of the electromagnetic shielding property in the warp direction and the weft direction)]×100) are shown in Tables 1 and 2. The measurement results at 100 KHz, 100 MHz and 1 GHz in Examples 1 to 5, and the measurement results at 15 GHz in Examples 1 to 5 and Comparative Examples 1 and 2 are shown in Table 1. The measurement results at 40 GHz and 110 GHz in Examples 1 and 5 are shown in Table 2. The average value A of the electromagnetic shielding property in the warp direction and the electromagnetic shielding property in the weft direction at 15 GHz in Examples 1 to 5 was 18.0 dB or more.

[0088] <Evaluation of Resin Affinity> Resin affinity was evaluated using the following procedure. First, a 0.2 mm-thick soft vinyl chloride resin film (a film obtained by calendering a soft vinyl chloride resin composition containing 100 parts by mass of soft vinyl chloride resin with a degree of polymerization of 1050 and 50 parts by mass of plasticizer (diisononyl 1,2-cyclohexanedicarboxylate) at a temperature of 180 to 190°C) was placed on both sides of the above-mentioned evaluation fabric, and then heat-pressed using a laminator at a temperature of 180 to 190°C to obtain an evaluation film material. Furthermore, a reference fabric was prepared by replacing the conductive yarn used in the evaluation fabric with a nonflammable yarn having the same average fineness as the conductive yarn (a nonflammable yarn made of the same material as the nonflammable yarn used in the evaluation fabric). The above-mentioned soft vinyl chloride resin film was placed on both sides of the reference fabric, and then heat-pressed using a laminator at a temperature of 180 to 190°C to obtain a reference film material. The tensile strength of the above-mentioned evaluation membrane material and reference membrane material was measured using the coating layer adhesion strength measurement method stipulated by the Japan Membrane Structures Association, which is based on the quality standards for membrane materials. When the tensile strength of the reference membrane material was used as the standard, and the variability of the tensile strength of the evaluation membrane material ([(tensile strength of reference membrane material - tensile strength of evaluation membrane material) / tensile strength of reference membrane material] x 100) was 30% or less, the resin affinity of the evaluation fabric was judged to be "A." When the variability was greater than 30%, the resin affinity of the evaluation fabric was judged to be "B." The results are shown in Table 1.

[0089] <Evaluation of Non-flammability> Using a cone calorimeter (manufactured by Toyo Seiki Seisakusho, Ltd.), the non-flammability of the evaluation fabrics (size: 99 mm x 99 mm) described above in Examples 1 to 5 was evaluated in accordance with ISO 5660-1 (heat generation test). Specifically, based on the total heat generation amount, heat generation rate, and deformation of the evaluation fabric for 20 minutes from the start of heating, a "total heat generation amount of 2 MJ / m ２ "heat generation rate is 200kW / m or less" ２ A case where all three requirements, "the time for which the temperature continuously exceeds the specified value is less than 10 seconds" and "there is no harmful deformation that would allow the flame to penetrate," were met was rated as "A," and a case where even one of the three requirements was not met was rated as "B." The results are shown in Table 1.

[0090]

[0091]

[0092] 1...electromagnetic wave shielding fabric, 3...warp yarns (conductive warp yarns, non-flammable warp yarns), 5...weft yarns (conductive weft yarns, non-flammable weft yarns), 7...plied and twisted yarns, 71...conductive yarns, 73...non-flammable yarns, A, A1, A2, A3, A4, A5, A6, A7, A11, A12, A13...surrounding areas, FS...front side position portion, BS...back side position portion, FP...front side non-intersecting portion, BP...back side non-intersecting portion.

Claims

1. A textile fabric comprising a plurality of warp threads extending in a first direction and arranged in a second direction intersecting the first direction, and a plurality of weft threads extending in the second direction and arranged in the first direction, the warp threads and the weft threads being formed of at least one of conductive threads and non-flammable threads, a plurality of surrounding regions being formed by the conductive threads adjacent to each other in the first direction and the conductive threads adjacent to each other in the second direction, and the average area of ​​the surrounding regions when viewed from a third direction perpendicular to both the first direction and the second direction is 0.075 to 2.000 mm ２ It is an electromagnetic wave shielding fabric.

2. The average area of ​​the surrounding region is 0.309 to 0.532 mm ２ The electromagnetic wave shielding fabric according to claim 1 , 3. The electromagnetic shielding fabric according to claim 1, wherein at least one of the warp yarns and the weft yarns is a ply-twisted yarn obtained by plying the conductive yarn and the non-flammable yarn.

4. An electromagnetic wave shielding fabric as described in claim 3, wherein the warp yarns and the weft yarns are ply-twisted yarns, and the conductive yarns adjacent to each other in the first direction and the conductive yarns adjacent to each other in the second direction are the conductive yarns of the ply-twisted yarns.

5. The electromagnetic shielding fabric according to claim 1, wherein at least one of the warp yarns and the weft yarns includes a metal-coated yarn having a core yarn coated with a metal material, the core yarn is made of an organic material, and the non-flammable yarn is made of glass.

6. A resin-attached fabric comprising: an electromagnetic wave shielding fabric according to any one of claims 1 to 5; and a resin portion attached to at least a portion of the electromagnetic wave shielding fabric.

Images