Conductive cloth

Abstract

Provided is a conductive fabric in which fluctuations in conductivity are suppressed. The conductive cloth is formed by wrapping a base material formed by weaving or weaving a yarn with a metal, the base material has a substantially non-elongated structure and an opening part formed in the structure, and the conductive cloth is configured such that the base material is elongated by deformation of the opening part when the base material is stretched.

Description

Technical Field

[0001] The present invention relates to a conductive cloth. Background Art

[0002] Conventionally, conductive fabrics made by coating knitted fabrics or woven fabrics with metal have been used as electromagnetic wave shielding materials, sensor materials, electrode materials, etc. Such conductive fabrics have a problem in that the conductivity changes due to deformation such as bending or twisting, and a conductive fabric that can solve this problem has been proposed.

[0003] For example, a conductive mesh textile (conductive cloth) is proposed, in which a metal coating is formed on a textile (substrate) having twisted yarns (yarns) composed of synthetic fiber filaments as warp yarns and weft yarns, the opening ratio is 40 to 80%, and there are recessed portions on each surface of the warp yarn and the weft yarn at the portion where the warp yarn and the weft yarn intersect (see patent document 1).

[0004] Prior Art Literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2022 / 270461 Summary of the invention

[0007] Problems to be solved by the invention

[0008] In the textile of Patent Document 1, if the textile is stretched along with deformation such as bending or twisting, the warp and weft may be inadvertently sparse, and the position of the contact point (the crossing position of the yarn, the electrical contact point) may change due to the sparse warp and weft, and the conduction may become unstable. On the other hand, in the case where a metal coating is formed on the knitted fabric, if the knitted fabric is stretched along with deformation such as bending or twisting, the loop may be inadvertently loosened, and the position of the contact point may change due to the change in the shape of the loop, and the conduction may become unstable.

[0009] Furthermore, in these woven and knitted fabrics, if the warp and weft become sparse or the loops are deformed, there is a possibility that cracks or other damage will occur in the metal coating, and the resistance value will increase.

[0010] In this way, there is a possibility that the conductivity may fluctuate due to a change in conduction from the non-stretched state or an increase in resistance value, thereby causing a decrease in the quality of the conductive cloth.

[0011] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a conductive cloth in which the variation in conductivity is suppressed.

[0012] Solutions to Solve Problems

[0013] The characteristic structure of the conductive cloth of the present invention for solving the above-mentioned problems is that a base material formed by knitting or weaving yarns is coated with metal.

[0014] The substrate has a substantially non-stretchable structure and an opening formed in the structure.

[0015] The conductive cloth is configured so as to deform through the openings when the base material is stretched, thereby extending the base material.

[0016] According to the conductive cloth of this structure, when the conductive cloth is stretched, the yarns constituting the structure do not substantially stretch, and the conductive cloth is substantially stretched only by deformation of the openings, thereby suppressing the thinning of the warp and weft or the deformation of the coils accompanying the stretch, thereby suppressing the change of the position (electrical contact) where the yarns cross. In addition, since the structure does not substantially stretch, damage such as cracking of the metal coating accompanying the stretch is suppressed. Therefore, the conductive cloth suppresses the change of conductivity.

[0017] In the conductive cloth of the present invention,

[0018] Preferably, the opening ratio of the substrate when not stretched is 40 to 95%.

[0019] As described above, the degree of deformation of the opening portion is equivalent to the degree of elongation of the conductive cloth. According to the conductive cloth of this structure, by setting the opening ratio of the substrate in the non-elongated state within the above range, the degree of elongation of the conductive cloth can be made more appropriate, so that the change in the conductivity of the conductive cloth is further suppressed. In addition, the amount of metal coating can be relatively reduced.

[0020] In the conductive cloth of the present invention,

[0021] Preferably, in the substantially non-stretchable structure, an elongation ratio of the side of the opening when the substrate is elongated by 20% to the side of the opening when the substrate is not elongated is set to 0.90 to 1.10.

[0022] According to the conductive cloth of this structure, by setting the elongation ratio of the opening side when the substrate is stretched by 20% to that when not stretched within the above range, a substantially non-stretchable structure can be achieved, resulting in reliable suppression of damage such as cracking of the metal coating.

[0023] In the conductive cloth of the present invention,

[0024] Preferably, the tension of the substrate when stretched by 20% in at least one of the warp direction, the weft direction and the diagonal direction is 10 N / cm or less.

[0025] According to the conductive cloth of this structure, by setting the tension when the base material is stretched by 20% in at least one of the warp direction, the weft direction and the diagonal direction within the above range, the opening can be deformed with a smaller load. As a result, it is possible to avoid applying an excessive load to stretch the conductive cloth, thereby further suppressing damage to the metal coating.

[0026] In the conductive cloth of the present invention,

[0027] Preferably, the elongation of the substrate, which is a ratio of the length when stretched to change the resistance value by 50% to the length when not stretched, is 15% or more in any of the warp, weft, and diagonal directions.

[0028] According to the conductive cloth of the present structure, by setting the ratio of the length of the substrate when stretched in a manner that changes the resistance value by 50% to the length when not stretched, that is, the elongation, in any direction of the warp, weft and diagonal directions to the above-mentioned range, the change of the resistance value when stretched relative to that when not stretched can be further suppressed.

[0029] In the conductive cloth of the present invention,

[0030] Preferably, the surface resistivity (Rs) of the substrate in the non-stretched state in the longitudinal direction, the latitudinal direction and the oblique direction is 10Ω / □ or less.

[0031] According to the conductive cloth of this structure, by setting the surface resistivity (Rs) of the base material in the warp, weft and oblique directions when not stretched to the above range, it can more appropriately function as an electromagnetic wave shielding material, sensor material, electrode material, etc.

[0032] In the conductive cloth of the present invention,

[0033] Preferably, the minimum inner diameter of the opening when not telescoped is 0.5 to 5 mm.

[0034] According to the conductive cloth of this configuration, by setting the minimum inner diameter of the opening in the non-stretching state within the above range, the degree of stretching of the conductive cloth can be made more appropriate.

[0035] In the conductive cloth of the present invention,

[0036] Preferably, the base material is a tulle mesh or marquisette knitted fabric in which a part of the yarn forms a loop and another part of the yarn is inserted into the loop.

[0037] According to the conductive cloth of this structure, by selecting a hexagonal mesh knitted fabric or a gauze knitted fabric as a base material, even if the conductive cloth is stretched, the change in the position of the yarn crossing can be further suppressed, and thus the change in the position of the contact point can be further suppressed. Therefore, the conductive cloth further suppresses the change in conductivity.

[0038] In the conductive cloth of the present invention,

[0039] Preferably, the conductive cloth is used as a sensor material, a monitoring material, a shielding material or an electrode material.

[0040] According to the conductive cloth of this structure, it is possible to provide a sensor material, a monitoring material, a shielding material, or an electrode material in which the change of conductivity is suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 These are photographs showing the conductive cloths of Examples 1 and 5 of the present invention. DETAILED DESCRIPTION

[0042] Hereinafter, the conductive cloth of the present invention will be described. However, the present invention is not intended to be limited to the structure described below and the Examples described later.

[0043] <Conductive fabric>

[0044] The conductive cloth of the present embodiment is formed by coating a base material formed by knitting or weaving yarns with metal. It should be noted that the base material formed by knitting or weaving yarns coated with metal may be directly used as the conductive cloth.

[0045] (Base material)

[0046] The substrate is formed by knitting or weaving yarns. That is, the substrate is a woven fabric or a textile. The substrate has a substantially non-stretchable structure and an opening formed in the structure, and is configured so that when the substrate is stretched, the opening is deformed to stretch the substrate.

[0047] Here, "the tissue does not substantially stretch" is not limited to no stretch at all, and stretching to a degree that does not affect conductivity is allowed. Specifically, when the length of each side of the opening that constitutes the substrate when the substrate is stretched by 20% in the warp, weft, and diagonal directions (L1, i.e., the length when stretched by 20%) to the length of each side before stretching (non-stretched) (L0) (L1 / L0) is in the range of 0.90 to 1.10 (i.e., the stretching ratio (L1 / L0) of each side of the opening when stretched by 20% to each side of the opening when non-stretched is 0.90 to 1.10) is included in "the tissue does not substantially stretch". It should be noted that when the substrate is stretched by 20%, sometimes part of each side stretches and the other part shrinks, but such a method is also included in "the tissue does not substantially stretch". In addition, depending on the weaving structure, the base material may not be stretched in any of the warp direction, the weft direction, and the diagonal direction. However, such a method means that "the structure does not substantially stretch" in the direction.

[0048] As the constituent material of the yarn, polyester fiber, polyamide fiber, polyethylene fiber, polyolefin fiber, polyurethane fiber, etc. can be cited, among which polyester fiber and polyamide fiber are preferred. These fibers can be used alone or in combination or in a blended or mixed form.

[0049] The fineness of the yarn is preferably 15 to 85 dtex, more preferably 20 to 60 dtex. By setting the fineness of the yarn to the above range, the strength of the conductive fabric can be increased, and the increase in the resistance value in the non-stretched state relative to the stretched state can be further suppressed.

[0050] The number of filaments of the yarn is preferably 2 to 40 f (filaments), more preferably 6 to 36 f (filaments). By setting the number of filaments of the yarn in the above range, the strength of the conductive fabric can be increased and the increase in the resistance value in the non-stretched state relative to the stretched state can be further suppressed.

[0051] As the yarn, raw yarn, crimped yarn, etc. can be used. Among them, crimped yarn is preferred. When crimped yarn is used as the yarn, the crimped yarn shrinks by heat shrinking, and the loops of the knitted structure are tightened, thereby suppressing the elongation of each side of the opening of the conductive cloth.

[0052] When the base material is a braided fabric, the base material can be braided using a tricot knitting machine, a raschel knitting machine, a circular knitting machine, etc. Among them, from the aspect of being able to make the opening larger, it is preferably braided using a tricot knitting machine or a raschel knitting machine. As the shape of the opening, a circle (such as a circle, an ellipse), a triangle, a quadrilateral, a pentagon, a hexagon (honeycomb structure), etc. can be cited. The base material is preferably a braided fabric formed by forming a coil with a part of the yarn and inserting the coil with another part of the yarn (inserted yarn), and as the braided fabric, a hexagonal mesh braided fabric with a hexagonal opening or a gauze braided fabric with a quadrilateral opening is preferably used.

[0053] The hexagonal mesh braid can be stretched in any direction of 360° by deformation of the opening. That is, it can be stretched at an angle other than the warp or weft of the braid (the angle intersecting the warp or weft). On the basis of being able to stretch in this way, the resistance value during stretching changes less than that during non-stretching. The gauze braid can be stretched obliquely by deformation of the opening. By thermally shrinking these hexagonal mesh braids and gauze braids, the coils of the woven structure are tightened, and the area outside the opening of the conductive cloth is further suppressed from stretching. As a result, the change of the intersection position (contact point) of the yarn accompanying the stretching can be further suppressed, and the damage of the metal coating accompanying the stretching can be further suppressed. In this way, by selecting the hexagonal mesh braid and the gauze braid as the base material, the conductive cloth further suppresses the change of conductivity. In addition, by selecting the hexagonal mesh braid and the gauze braid, the opening can be further enlarged, so the amount of metal coating can be reduced accordingly.

[0054] The yarn is preferably a yarn that does not stretch substantially. Specifically, it is preferably a yarn whose elongation ratio (L1 / L0) of each side of the opening when stretched 20% in the warp, weft, and oblique directions relative to each side of the opening when not stretched satisfies 0.90 to 1.10 as described above. The yarn is obtained by heat shrinking the base material. The conductive cloth is further stretched only by deformation of the opening, thereby further suppressing changes in conductivity.

[0055] As described above, when heat shrinking the base material, the heating temperature and the heating pressure can be appropriately set to the following conditions: the yarn does not substantially stretch, the loop can be tightened, and the yarn is not damaged.

[0056] When not stretched, the minimum inner diameter of the opening is preferably 0.5 to 5 mm. The minimum inner diameter of the opening refers to the diameter of a circle inscribed in the opening. By setting the minimum inner diameter of the opening when not stretched to the above range, the degree of elongation of the conductive fabric can be made more appropriate.

[0057] The weight per unit area of ​​the substrate is preferably 1 to 50 g / m2 , more preferably 6 to 42 g / m 2 By setting the weight per unit area of ​​the substrate within the above range, the strength of the substrate can be made appropriate, and the amount of the metal coating coated on the substrate can be made appropriate. It should be noted that, in the case of heat shrinkage of the substrate, the above weight per unit area is the weight per unit area after heat shrinkage.

[0058] The opening ratio (S0) of the substrate when not stretched is preferably 40 to 95%. As described above, the degree of deformation of the opening portion is equivalent to the degree of stretching of the conductive cloth. By setting the opening ratio of the substrate when not stretched to the above range, the degree of stretching of the conductive cloth can be made more appropriate, so the change in the conductivity of the conductive cloth is further suppressed. In addition, the amount of metal coating can be relatively reduced.

[0059] (Metal coating)

[0060] As the metal constituting the metal coating, gold, silver, copper, platinum, nickel, zinc, tin, etc. can be cited. The metal can be used alone or in combination. When using two or more metals, it can be divided into multiple layers for use, or it can be an alloy containing multiple metals. Among them, the metal is preferably copper or nickel, and more preferably a metal coating having a nickel coating laminated on a copper coating.

[0061] The amount of metal in the metal coating is preferably 2 to 30 g / m 2 When the metal coating is formed by laminating nickel on copper, the amount of copper is preferably 1.5 to 28 g / m 2 The nickel content is preferably 0.3 to 5 g / m 2 By setting the metal amount within the above range, the flexibility can be made more appropriate and the conductivity of the conductive cloth can be made more appropriate.

[0062] The thickness of the metal coating is preferably 0.5 to 2 μm. By setting the thickness of the metal coating to the above range, the flexibility can be made more appropriate and the conductivity of the conductive cloth can be made more appropriate.

[0063] As the method for forming the metal coating, the method of evaporation, sputtering, electroplating, chemical plating etc. can be cited. Among them, from the aspect of being able to form a more uniform metal coating in all directions on the surface of the substrate, chemical plating and / or electroplating are preferred. In addition, it is preferred that after chemical plating is initially performed on the substrate, electroplating is then performed, so that the metal coating becomes a multilayer structure, and more preferably, after chemical copper plating is performed, nickel electroplating is performed.

[0064] When performing chemical copper plating and electroplating nickel, first, a colloidal solution containing lead chloride (PbCl2) and tin chloride (SnCl2) is used to impart a catalyst for chemical plating to the substrate, and then chemical copper plating and then electroplating nickel can be performed continuously. For chemical copper plating, an electroplating solution containing copper chloride (CuCl2), formaldehyde, and sodium hydroxide can be used. For electroplating nickel, an electroplating solution containing nickel sulfate hexahydrate (NiSO4•6H2O) and sodium citrate can be used.

[0065] (Characteristics of conductive fabric)

[0066] The ratio (S1 / S0) of the opening ratio (S1) of the substrate (i.e., the conductive fabric) when stretched by 20% to the opening ratio (S0) when not stretched is preferably 0.5 to 1 in any one of the warp direction, the weft direction, and the diagonal direction. By setting the ratio (S1 / S0) within the above range, the degree of deformation of the opening portion accompanying the stretching can be made more appropriate.

[0067] The tension when the substrate is stretched by 20% in at least one of the warp, weft and diagonal directions is preferably 10 N / cm or less. By setting the tension when the substrate is stretched by 20% in at least one of the warp, weft and diagonal directions to the above range, the opening can be deformed with less load. As a result, an excessive load is not applied to stretch the conductive cloth, and damage to the metal coating can be further suppressed.

[0068] The ratio of the length (W1) of the substrate when stretched in a manner in which the resistance value changes by 50% to the length (W0) when it is not stretched, i.e., the elongation E (W1 / W0×100), is preferably 15% or more in any direction among the warp, weft, and diagonal directions. That is, the elongation E relative to the non-stretched state when the resistance value changes by 50% is preferably 15% or more in any direction among the warp, weft, and diagonal directions. By setting the elongation E to the above range, the change in the resistance value during stretching relative to that during non-stretching can be further suppressed. It should be noted that, depending on the weaving structure, it is sometimes impossible to stretch the substrate in any direction among the warp, weft, and diagonal directions, but in such a case, the resistance value does not change in the direction that cannot be stretched.

[0069] The surface resistivity (Rs) of the substrate in the non-stretched state in the longitudinal, latitudinal and oblique directions is preferably 10Ω / □ or less. Here, the unit of surface resistivity (Rs) "Ω / □" refers to ohms per square (ohms per unit area (1cm 2 By setting the surface resistivity (Rs) of the substrate in the non-stretched state in the longitudinal direction, the latitudinal direction and the oblique direction to the above range, the variation of the resistance value in the non-stretched state relative to the stretched state can be further suppressed.

[0070] (Production of conductive fabric)

[0071] The conductive cloth according to the present embodiment is obtained, for example, as follows.

[0072] •Making of substrate

[0073] The yarns are braided or woven using a braiding machine or a textile machine to obtain a woven fabric or a textile (base material) having a desired braided or woven structure.

[0074] •Preparation

[0075] The obtained base material is subjected to a scouring process and a heat shrinking (heat setting) process. Specifically, first, a scouring process is performed to clean the base material by washing off the oil agent attached to the yarn using a predetermined chemical aqueous solution and appropriately setting the liquid temperature conditions. Then, a heat shrinking process is performed at a predetermined temperature for a predetermined time so as to obtain the desired course and wale.

[0076] •Electroplating

[0077] Next, a catalyst for chemical plating is applied to the heat-shrunk substrate using a predetermined colloidal solution, and then electroplating is performed. For example, chemical plating and then electroplating are performed continuously.

[0078] In this way, a conductive cloth can be obtained.

[0079] (Application of conductive fabric)

[0080] The use of the conductive cloth is not particularly limited, and the conductive cloth can be used as a sensor material such as a touch sensor, a monitoring material such as a monitoring system, a shielding material, an electrode material, and the like.

[0081] [Example]

[0082] [Example 1]

[0083] (Making of knitted fabrics)

[0084] As shown in Table 1, a crimped yarn of polyethylene terephthalate filament (PET, 33 dtex / 12f) was used as the yarn, and a single bar tricot machine was used to obtain a hexagonal mesh knitted fabric with a course of 70C and a length of 30W by a hexagonal mesh knitting structure.

[0085] (Preparatory processing)

[0086] The obtained knitted fabric was subjected to a scouring process and a heat shrinking (heat setting) process. Specifically, first, a chemical aqueous solution containing 0.3% by mass of a soaping agent (LIPOTOL TC-350, manufactured by Nikka Chemical Co., Ltd.) and 0.1% by mass of a chelating agent (SJ Chelate A, manufactured by Seiren Shoji Co., Ltd.) was used, and the liquid temperature condition was set to 80°C to perform a scouring process to clean the knitted fabric by washing away the oil agent attached to the yarn of the knitted fabric. Then, a heat shrinking process was performed at a temperature of 200°C for 1 minute in a manner that the row of stitches was 78C and the length of stitches was 20W.

[0087] (Electroplating processing)

[0088] Next, a catalyst for chemical plating is applied to the heat-shrunk braid using a colloidal solution containing lead chloride (PbCl2) and tin chloride (SnCl2), and then chemical copper (Cu) plating and then nickel (Ni) electroplating are successively performed to perform electroplating processing to achieve the metal amount shown in Table 1. In chemical copper plating, a plating solution containing copper chloride (CuCl2), formaldehyde, and sodium hydroxide is used. In nickel electroplating, a plating solution containing nickel sulfate hexahydrate (NiSO4•6H2O) and sodium citrate is used.

[0089] Thus, the conductive cloth of Example 1 was obtained. A photograph of the conductive cloth of Example 1 is shown in FIG. Figure 1 As shown in (a).

[0090] [Examples 2 to 4]

[0091] Except having changed into the conditions shown in Table 1, it carried out similarly to Example 1, and obtained the conductive cloth of Examples 2-4.

[0092] [Example 5]

[0093] (Making of knitted fabrics)

[0094] As shown in Table 2, a crimped yarn of polyethylene terephthalate filament (PET, 33 dtex / 6f) was used as the yarn, and a single bar raschel warp knitting machine was used to obtain a gauze leno knitted fabric with a course of 50C and a warp of 6W through a gauze leno knitting structure.

[0095] (Preparatory processing)

[0096] The obtained knitted fabric was subjected to scouring and heat shrinking (heat setting) in the same manner as in Example 1. In the heat shrinking, the knitted fabric was subjected to heat shrinking so that the course was 52C and the length was 6W.

[0097] (Electroplating processing)

[0098] Next, electroless copper (Cu) plating and then nickel (Ni) electroplating were successively performed on the heat-shrunk braid in the same manner as in Example 1, thereby performing electroplating processing so that the metal amounts shown in Table 2 were obtained.

[0099] Thus, the conductive cloth of Example 5 was obtained. A photograph of the conductive cloth of Example 5 is shown in Figure 1 (b).

[0100] [Examples 6 to 9]

[0101] Except having changed into the conditions shown in Table 2, it carried out similarly to Example 5, and obtained the conductive cloth of Examples 6-9.

[0102] [Comparative Example 1]

[0103] (Making of knitted fabrics)

[0104] As shown in Table 3, crimped yarn of polyethylene terephthalate filament (PET, 33 dtex / 12f) was used as the yarn, and a plain knitted fabric with a course of 85C and a length of 60W was obtained by a circular knitting machine through plain knitting structure.

[0105] (Preparatory processing)

[0106] The obtained knitted fabric was subjected to a scouring process and a heat shrinking (heat setting) process in the same manner as in Example 1. In the heat shrinking process, the heat shrinking process was performed so that the course was 90C and the length was 42W.

[0107] (Electroplating processing)

[0108] Next, electroless copper (Cu) plating and then nickel (Ni) electroplating were continuously performed on the heat-shrunk braid in the same manner as in Example 1, thereby performing electroplating processing so that the metal amounts shown in Table 3 were obtained.

[0109] [Comparative Examples 2 to 4]

[0110] (Making of knitted fabrics)

[0111] As shown in Table 3, crimped yarn of polyethylene terephthalate filament (PET, 33 dtex / 12f) was used as the yarn, and the knitting machine shown in Table 3 was used to obtain the knitted fabric shown in Table 3 with the knitting structure shown in Table 3.

[0112] (Preparatory processing)

[0113] The obtained knitted fabric was subjected to scouring and heat shrinking (heat setting) in the same manner as in Example 1. In the heat shrinking, the knitted fabric was subjected to the heat shrinking so as to have the courses and wales shown in Table 3.

[0114] (Electroplating processing)

[0115] Next, electroless copper (Cu) plating and then nickel (Ni) electroplating were continuously performed on the heat-shrunk braid in the same manner as in Example 1, thereby performing electroplating processing so that the metal amounts shown in Table 3 were obtained.

[0116] The conductive fabrics of Examples 1 to 9 and Comparative Examples 1 to 4 were evaluated as follows. The results are shown in Tables 1 to 3. It should be noted that in Table 2, the gauze fabrics of Examples 5 to 9 were not stretched in the warp and weft directions, so these directions were not evaluated and recorded as "-". In Table 3, the plain needle fabric and warp-pile plain fabric of Comparative Example 1 did not have openings, so the opening ratio was not evaluated and recorded as "-".

[0117] [Aperture ratio]

[0118] The surface of the conductive fabric was photographed at 50 times magnification using a microscope (product name: Dino-Lite, manufactured by Anmo Electronics). The obtained image was used to measure the area of ​​the fibers and the area of ​​the openings in the image using image processing software (product name: Dino Capture 2.0, manufactured by Anmo Electronics), and the aperture ratio was calculated according to the following formula (1).

[0119] Opening ratio (%) = (opening area) / (opening area + fiber area) × 100••• (1)

[0120] In this way, the opening rate (S0) when not stretched and the opening rate (S1) when stretched by 20% are measured in each direction shown in Tables 1 to 3, and the ratio (S1 / S0) of the opening rate (S1) when stretched by 20% to the opening rate (S0) when not stretched is calculated. It should be noted that the gauze knitted structure of Examples 5 to 9 cannot be stretched in the warp and weft directions, so the opening rate ratio (S1 / S0) is only measured in the oblique direction. The plain knitted structure of Comparative Example 1 and the warp plain knitted structure of Comparative Example 2 do not form an opening (the opening rate (S0) is 0%), so the opening rate ratio (S1 / S0) is not measured.

[0121] [Tension at 20% elongation]

[0122] The conductive fabric was cut into a size of 2.5 cm in width and 15 cm in length in the warp direction, weft direction, and diagonal direction to obtain test pieces. The test pieces were placed on the chucks of an Autograph (product name: AG-IS, manufactured by Shimadzu Corporation) with a chuck distance of 10 cm, and the distance between the chucks was 100 mm in each direction shown in Tables 1 to 3. 2The test piece was stretched at a speed of 20% / min, and the strength N when the test piece was stretched by 20% was measured. The tension (N / cm) when stretched by 20% was calculated by dividing the measured value by 2.5 cm. It should be noted that the gauze woven structures of Examples 5 to 9 cannot be stretched in the warp and weft directions, so the tension when stretched by 20% was measured only in the oblique direction.

[0123] [Elongation ratio of each side of the opening when stretched by 20% to each side of the opening when not stretched (L1 / L0)]

[0124] Similar to the above-mentioned "opening ratio", a test piece (width 2.5 cm × length 15 cm) obtained in the same manner as the above-mentioned "tension at 20% elongation" is photographed at 50 times using a microscope, and the length of each side in the obtained image is measured, thereby measuring the length of each side when not stretched (L0). Next, the test piece is stretched in the same manner as the above-mentioned "tension at 20% elongation", and the test piece is photographed when the test piece is stretched by 20% in the same manner as the above-mentioned non-stretched state, and the length of each side in the obtained image is measured, thereby obtaining the length of each side when stretched by 20%. Then, the elongation ratio (L1 / L0) of each side of the opening portion at 20% elongation relative to each side of the opening portion at non-stretching is calculated. It should be noted that the length of one of the opposing sides in the opening portion is the same as the length of the other side, so only the length of any one side is measured. That is, the lengths of three sides are measured in the case of a hexagonal mesh woven structure, and the lengths of two sides are measured in the case of a gauze woven structure. It should be noted that the gauze leno knitted structures of Examples 5 to 9 cannot be stretched in the warp and weft directions, so the elongation ratio (L1 / L0) was only measured in the diagonal direction. The plain knitted structure of Comparative Example 1 and the warp plain knitted structure of Comparative Example 2 did not form an opening (the opening ratio (S0) was 0%), so the elongation ratio (L1 / L0) was not measured.

[0125] [Surface resistivity (Rs)]

[0126] The surface resistivity (Rs) in the non-stretched state was measured using a low resistivity meter (product name: Lorestar MCP-T360, manufactured by Mitsubishi Chemical Corporation).

[0127] [Elongation E relative to non-stretching when resistance value changes by 50%]

[0128] With respect to the test piece (width 2.5cm×length 15cm) obtained in the same manner as the above-mentioned "tension at 20% elongation", a copper foil tape is pasted in the width direction at intervals of 10cm in the length direction. The test piece is set on the chuck of the above-mentioned automatic plotter with a clamping width of 12cm, and the resistance value (Ω) between the copper foil tapes is measured using a tester while the test piece is stretched to obtain the length of the test piece (W1, i.e., the clamping width) when the resistance value changes by 50% from before stretching (non-stretching, i.e., at the beginning of the measurement). Then, the ratio of the length when the resistance value changes by 50% to the length of the test piece when it is non-stretched (W0, i.e., the clamping width of 12cm) is calculated as the elongation E (W1 / W0×100). It should be noted that the gauze woven structure of Examples 5 to 9 cannot be stretched in the warp and weft directions, so the elongation E is only measured in the diagonal direction.

[0129] [Table 1]

[0130]

[0131] [Table 2]

[0132]

[0133] [Table 3]

[0134]

[0135] As shown in Tables 1 and 2, the conductive fabrics of Examples 1 to 4 showed that the elongation E relative to the non-stretching state when the resistance value changed by 50% was 15% or more in any of the warp, weft, and diagonal directions in which these conductive fabrics can be stretched, and the change in conductivity during stretching was suppressed. The conductive fabrics of Examples 5 to 9 showed that the elongation E relative to the non-stretching state when the resistance value changed by 50% was 15% or more in the diagonal directions in which these conductive fabrics can be stretched, and the change in conductivity during stretching was suppressed.

[0136] In contrast, as shown in Table 3, the conductive cloths of Comparative Examples 1 to 4, which have no openings or are substantially stretched even if they have openings, show that when the resistance value changes by 50%, the elongation E relative to the non-stretched state is less than 15% in at least two directions of the warp, weft, and diagonal directions, and the change in conductivity is not suppressed during stretching.

[0137] [Industrial Applicability]

[0138] The conductive cloth of the present invention can be suitably used as, for example, a sensor material, a monitoring material, a shielding material, or an electrode material.

Claims

1. A conductive cloth, which is formed by coating a base material formed by knitting or weaving yarns with a metal, wherein: The substrate has a substantially non-stretchable structure and an opening formed in the structure. The conductive cloth is configured so as to deform through the openings when the base material is stretched, thereby extending the base material.

2. The conductive cloth according to claim 1, wherein The opening ratio of the substrate when not stretched is 40 to 95%.

3. The conductive cloth according to claim 1, wherein In the substantially non-stretchable structure, the elongation ratio of the side of the opening when the substrate is elongated by 20% to the side of the opening when the substrate is not elongated is set to 0.90 to 1.

10.

4. The conductive cloth according to claim 1, wherein The tension of the substrate when stretched 20% in at least one of the warp direction, the weft direction, and the diagonal direction is 10 N / cm or less.

5. The conductive cloth according to claim 1, wherein The elongation of the substrate, which is a ratio of the length when stretched so that the resistance value changes by 50% to the length when not stretched, is 15% or more in any of the warp direction, the weft direction, and the diagonal direction.

6. The conductive cloth according to claim 1, wherein The surface resistivity Rs of the substrate in the non-stretched state in the longitudinal direction, the latitudinal direction and the oblique direction is 10Ω / □ or less.

7. The conductive cloth according to claim 1, wherein The minimum inner diameter of the opening when not telescoped is 0.5 to 5 mm.

8. The conductive cloth according to claim 1, wherein The base material is a hexagonal mesh knitted fabric or a tulle knitted fabric in which a part of the yarn forms a loop and another part of the yarn is inserted into the loop.

9. The conductive cloth according to any one of claims 1 to 8, wherein The conductive cloth is used as a sensor material, a monitoring material, a shielding material, or an electrode material.

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