Conductive fabric

Abstract

To provide a conductive fabric in which fluctuation of conductivity is suppressed.SOLUTION: A conductive fabric is produced by coating a substrate formed by knitting or weaving yarns with metal, where the substrate has a fabric structure which substantially does not elongate and openings formed in the fabric structure, and the conductive fabric is constituted such that the substrate elongates by deformation of the openings when the substrate is pulled.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a conductive fabric. [Background technology]

[0002] Conventionally, conductive fabrics, which are knitted or woven fabrics coated with metal, have been used as electromagnetic wave shielding materials, sensor materials, electrode materials, etc. This type of conductive fabric has a problem in that its conductivity changes with deformation such as bending or twisting, and conductive fabrics that can solve this problem have been proposed.

[0003] For example, a conductive mesh fabric (conductive cloth) has been proposed in which a metal coating is formed on a woven fabric (substrate) having twisted yarns (threads) made of synthetic fiber filaments as warp and weft threads, the opening ratio is 40 to 80%, and the surfaces of the warp and weft threads have recesses at the points where the warp and weft threads intersect (see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2022 / 270461 Summary of the Invention [Problem to be solved by the invention]

[0005] In the woven fabric of Patent Document 1, when the woven fabric stretches due to deformation such as bending or twisting, the yarns may be suddenly distorted, and the position of the contact point (the intersection point of the yarns, which is the electrical contact point) may change due to the yarns being distorted, which may cause unstable conduction. On the other hand, when a metal coating is formed on a knitted fabric, when the knitted fabric stretches due to deformation such as bending or twisting, the loops may suddenly loosen, and the position of the contact point may change due to the change in shape of the loops, which may cause unstable conduction.

[0006] Furthermore, in these woven and knitted fabrics, if the yarn becomes distorted or the loop becomes deformed, the metal coating may be damaged, such as by cracking, and the resistance value may increase.

[0007] In this way, the change in conductivity and the increase in resistance value from the non-stretched state due to stretching can lead to fluctuations in conductivity, which may lead to a decrease in the quality of the conductive fabric.

[0008] The present invention has been made in consideration of the above circumstances, and has an object to provide a conductive cloth in which fluctuations in conductivity are suppressed. [Means for solving the problem]

[0009] The characteristic configuration of the conductive cloth of the present invention to solve the above problems is as follows: A conductive cloth in which a base material formed by knitting or weaving a yarn is coated with a metal, The substrate has a substantially inextensible structure and an opening formed in the structure; The opening is configured so that, when the base material is pulled, the opening is deformed, thereby causing the base material to extend.

[0010] According to the conductive cloth of this configuration, when the conductive cloth is pulled, the threads constituting the structure do not substantially stretch, and the conductive cloth stretches substantially only due to the deformation of the openings, so that the yarns are prevented from being distorted or the loops are prevented from being deformed due to such stretching, and thus the change in the position where the threads cross (electrical contacts) is prevented. In addition, because the structure does not substantially stretch, damage such as cracks in the metal coating caused by such stretching is prevented. Therefore, the conductive cloth has a suppressed change in conductivity.

[0011] In the conductive cloth according to the present invention, The base material preferably has an opening ratio of 40 to 95% when unstretched.

[0012] As described above, the degree of deformation of the opening corresponds to the degree of stretching of the conductive cloth. According to the conductive cloth of this configuration, by setting the opening ratio when the base material is not stretched within the above range, the degree of stretching of the conductive cloth can be made more appropriate, so that the conductive cloth has more suppressed fluctuations in conductivity. In addition, the amount of metal coating can be relatively reduced.

[0013] In the conductive cloth according to the present invention, The substrate preferably has a tension of 10 N / cm or less at 20% elongation in at least one of the warp direction, the weft direction, and the oblique direction.

[0014] According to the conductive cloth of this configuration, by setting the tension at 20% elongation in at least one of the warp direction, weft direction, and diagonal direction of the base material within the above range, the opening can be deformed with less load. This makes it unnecessary to apply an excessive load to elongate the conductive cloth, and therefore damage to the metal coating can be further suppressed.

[0015] In the conductive cloth according to the present invention, It is preferable that the surface resistivity (Rs) of the substrate in the warp direction, weft direction and oblique direction when unstretched is 10 Ω / □ or less.

[0016] According to the conductive cloth of the present configuration, by setting the surface resistivity (Rs) of the substrate when unstretched in the warp direction, weft direction, and diagonal direction all within the above ranges, the cloth can more appropriately function as an electromagnetic wave shielding material, sensor material, electrode material, etc.

[0017] In the conductive cloth according to the present invention, It is preferable that the minimum inner diameter of the opening when not expanded or contracted is 0.5 to 5 mm.

[0018] According to the conductive cloth of this configuration, by setting the minimum inner diameter of the opening when not stretched within the above range, the degree of stretch of the conductive cloth can be made more appropriate.

[0019] In the conductive cloth according to the present invention, The base material is preferably a tulle mesh knit or marquisette knit in which a part of the yarn forms a loop and another part of the yarn is inserted into the loop.

[0020] According to the conductive cloth of this configuration, by selecting a tulle mesh fabric or a marquisette fabric as the base material, even if the conductive cloth is stretched, the change in the position where the yarns cross can be more effectively suppressed, and the change in the position of the contact can be more effectively suppressed. Therefore, the conductive cloth has more effectively suppressed fluctuations in conductivity. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is a photograph showing the conductive fabrics of Examples 1 and 5 of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The conductive cloth of the present invention will be described below. However, the present invention is not intended to be limited to the configuration described below or the examples described later.

[0023] <Conductive cloth> The conductive cloth of this embodiment is a conductive cloth in which a base material formed by knitting or weaving threads is coated with a metal. Note that a base material formed by knitting or weaving threads coated with a metal can also be used as the conductive cloth as it is.

[0024] (base material) The substrate is formed by knitting or weaving yarns. That is, the substrate is a knitted or woven fabric. Such a substrate has a substantially inelastic structure and openings formed in the structure, and is configured such that when the substrate is pulled, the openings deform, thereby allowing the substrate to stretch.

[0025] Here, "the texture does not substantially stretch" is not limited to complete stretching, and stretching that does not affect electrical conductivity is acceptable. Specifically, when the ratio (L1 / L0) of the length (L1, i.e., the length at 20% stretching) of each side constituting the opening of the substrate when the substrate is stretched by 20% in the warp direction, the weft direction, and the oblique direction to the length (L0) of each side before stretching (when not stretched) is in the range of 0.90 to 1.10 (i.e., when the stretch ratio (L1 / L0) of each side of the opening when stretched by 20% to when not stretched is 0.90 to 1.10), this is included in "the texture does not substantially stretch". Note that when the substrate is stretched by 20%, some of the sides may stretch and other parts may shrink, and such a mode is also included in "the texture does not substantially stretch". Depending on the knitting structure, the base material may not be able to be pulled in any of the warp, weft, and diagonal directions, and in such a case, the "structure does not substantially stretch" in that direction.

[0026] Examples of the raw materials for the yarn include polyester fibers, polyamide fibers, polyethylene fibers, polyolefin fibers, polyurethane fibers, etc., and among these, polyester fibers and polyamide fibers are preferred. These fibers may be used alone or in the form of a mixture or blend of two or more types.

[0027] The yarn fineness is preferably 15 to 85 dtex, more preferably 20 to 60 dtex. By setting the yarn fineness within the above range, the strength of the conductive cloth can be increased while further suppressing the increase in resistance value when not stretched relative to when stretched.

[0028] The number of filaments in the thread is preferably 2 to 40 f (pieces), and more preferably 6 to 36 f (pieces). By setting the number of filaments in the thread within the above range, it is possible to increase the strength of the conductive cloth while further suppressing the increase in resistance value when not stretched compared to when stretched.

[0029] As the thread, raw silk, crimped yarn, etc. can be used. Among these, crimped yarn is preferred. When crimped yarn is used as the thread, the crimped yarn is shrunk by heat shrinking, the loops of the knitted structure are tightened, and the extension of each side of the opening of the conductive cloth is suppressed.

[0030] When the substrate is a knitted fabric, the substrate can be knitted by a tricot knitting machine, a raschel knitting machine, a circular knitting machine, or the like. Of these, it is preferable to knit the substrate by a tricot knitting machine or a raschel knitting machine, since the opening can be made larger. The shape of the opening can be a circle (e.g., a circle or an ellipse), a triangle, a square, a pentagon, a hexagon (honeycomb structure), or the like. The substrate is preferably a knitted fabric in which a part of the yarn forms a loop and another part of the yarn (insertion yarn) is inserted into the loop, and such a knitted fabric is preferably a tulle mesh knitted fabric having a hexagonal opening, or a marquisette knitted fabric having a square opening.

[0031] The tulle mesh knitted fabric can be stretched in any direction of 360° by deformation of the opening. In other words, it can be stretched in an angle other than the warp or weft direction of the knitted fabric (an angle intersecting the warp or weft direction). In addition to being stretchable in this way, there is little change in resistance value when stretched compared to when not stretched. The marquisette knitted fabric can be stretched in an oblique direction by deformation of the opening. By thermally shrinking these tulle mesh knitted fabrics and marquisette knitted fabrics, the loops of the knitted fabric are tightened, and the stretch of the conductive cloth in the areas other than the openings is further suppressed. This further suppresses the change in the intersection position (contact point) of the yarns due to stretching, and also further suppresses damage to the metal coating due to stretching. In this way, by selecting the tulle mesh knitted fabric or marquisette knitted fabric as the base material, the conductive cloth has a further suppressed change in conductivity. In addition, by selecting the tulle mesh knitted fabric or marquisette knitted fabric, the opening can be made larger, and the amount of metal coating can be reduced accordingly.

[0032] The thread is preferably one that does not substantially stretch. Specifically, as described above, the thread is preferably one that satisfies an elongation ratio (L1 / L0) of each side of the opening when stretched by 20% relative to when not stretched in the warp direction, weft direction, and oblique direction of 0.90 to 1.10. Such thread is obtained by subjecting the substrate to heat shrinkage. The conductive cloth stretches only due to deformation of the opening, and therefore fluctuations in conductivity are further suppressed.

[0033] As described above, when the substrate is subjected to heat shrinkage, the heating temperature and pressure can be appropriately set under conditions such that the yarn is not substantially stretched, the loop can be tightened, and the yarn is not damaged.

[0034] The minimum inner diameter of the opening when not stretched is preferably 0.5 to 5 mm. The minimum inner diameter of the opening is the diameter of a circle inscribed in the opening. By setting the minimum inner diameter of the opening when not stretched within the above range, the degree of stretch of the conductive cloth can be made more appropriate.

[0035] The weight of the base material is 1 to 50 g / m 2 is preferable, and 6 to 42 g / m 2 It is more preferable that the weight per unit area of ​​the substrate is set within the above range, so that the strength of the substrate can be appropriately controlled and the amount of the metal coating film coated on the substrate can be appropriately controlled. Note that, in the case where the substrate is heat-shrunk, the above weight per unit area is the weight per unit area after heat shrinkage.

[0036] 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 corresponds to the degree of stretch of the conductive cloth. By setting the opening ratio of the substrate when not stretched within the above range, the degree of stretch of the conductive cloth can be made more appropriate, so that the conductive cloth has more suppressed fluctuations in conductivity. In addition, the amount of metal coating can be relatively reduced.

[0037] (Metal Film) Examples of metals constituting the metal coating include gold, silver, copper, platinum, nickel, zinc, and tin. The metals may be used alone or in combination. When two or more metals are used, they may be used in a plurality of layers or in the form of an alloy containing a plurality of metals. Of these, the metal is preferably copper or nickel, and more preferably a metal coating in which a nickel coating is laminated on a copper coating.

[0038] The amount of metal in the metal coating is 2 to 30 g / m 2 In addition, when the metal coating is made of nickel laminated on copper, the amount of copper is preferably 1.5 to 28 g / m 2 The amount of nickel is preferably 0.3 to 5 g / m 2 By setting the amount of metal within the above range, it is possible to make the flexibility more appropriate and the conductivity of the conductive cloth more appropriate.

[0039] The thickness of the metal coating is preferably 0.5 to 2 μm. By setting the thickness of the metal coating within the above range, the flexibility can be made more appropriate and the conductivity of the conductive cloth can be made more appropriate.

[0040] Methods for forming the metal coating include vapor deposition, sputtering, electroplating, electroless plating, etc. Among these, electroless plating and / or electroplating are preferred because they can form a more uniform metal coating in all directions on the surface of the substrate. It is also preferred to first apply electroless plating to the substrate and then electroplating to form a multi-layered metal coating, and it is more preferred to apply electroless copper plating and then electrolytic nickel plating.

[0041] When performing electroless copper plating or nickel electroplating, the base material is first coated with lead chloride (PbCl 2 ) and tin chloride (SnCl 2 The electroless plating catalyst is applied using a colloidal solution containing copper chloride (CuCl), and then electroless copper plating and then electrolytic nickel plating can be carried out in succession. 2), formaldehyde, and sodium hydroxide. In electroplating nickel, nickel sulfate hexahydrate (NiSO 4 6H 2 O) and sodium citrate may be used.

[0042] (Characteristics of conductive fabric) The ratio (S1 / S0) of the opening ratio (S1) when the substrate (i.e., the conductive cloth) is stretched by 20% to the opening ratio (S0) when the substrate is not stretched is preferably 0.5 to 1 in any one of the warp direction, weft direction, and oblique direction. By setting the ratio (S1 / S0) in the above range, the degree of deformation of the openings due to stretching can be made more appropriate.

[0043] The tension of the substrate at 20% elongation in at least one of the warp, weft, and diagonal directions is preferably 10 N / cm or less. By setting the tension of the substrate at 20% elongation in at least one of the warp, weft, and diagonal directions within the above range, the opening can be deformed with less load. This makes it unnecessary to apply an excessive load to elongate the conductive cloth, and therefore damage to the metal coating can be further suppressed.

[0044] The elongation rate E (W1 / W0 × 100), which is the ratio of the length (W1) when the base material is stretched so that the resistance value changes by 50% to the length (W0) when the base material is not stretched, is preferably 15% or more in any of the warp, weft, and diagonal directions. That is, the elongation rate E when the resistance value when the base material is not stretched changes by 50% is preferably 15% or more in any of the warp, weft, and diagonal directions. By setting the elongation rate E within the above range, the change in the resistance value when stretched compared to when the base material is not stretched can be further suppressed. Depending on the knitting structure, the base material may not be able to be pulled in any of the warp, weft, and diagonal directions. In such a case, it is assumed that there is no change in the resistance value in the direction in which the base material cannot be pulled.

[0045] The surface resistivity (Rs) of the substrate in the warp direction, weft direction, and oblique direction when unstretched is preferably 10 Ω / □ or less. By setting the surface resistivity (Rs) of the substrate in the warp direction, weft direction, and oblique direction when unstretched within the above ranges, the variation in the resistance value when unstretched relative to when stretched can be further suppressed.

[0046] (Making conductive cloth) The conductive cloth of this embodiment can be obtained, for example, as follows.

[0047] - Preparation of substrate The yarn is knitted or woven using a knitting machine or a loom to obtain a knitted or woven fabric (substrate) having a desired knitted or woven structure.

[0048] ·Preparation processing The obtained substrate is subjected to a refining process and a heat shrinking (heat setting) process. Specifically, a refining process is performed by using a predetermined aqueous solution of chemicals, setting the liquid temperature conditions appropriately, and washing off the oil agent adhering to the yarn of the substrate to clean the substrate. Next, the substrate is subjected to a heat shrinking process at a predetermined temperature for a predetermined time so as to obtain the desired course and well.

[0049] Plating Next, a catalyst for electroless plating is applied to the heat-shrunk substrate using a predetermined colloidal solution, and then plating is performed. For example, electroless plating and then electroplating are performed in succession.

[0050] In this manner, a conductive cloth can be obtained.

[0051] (Applications of conductive fabric) The applications of the conductive cloth are not particularly limited, but it 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. EXAMPLES

[0052] [Example 1] (Knitted Fabric Production) As shown in Table 1, a crimped yarn of polyethylene terephthalate filament (PET, 33 dtex / 12f) was used as the yarn, and a single tricot machine was used to obtain a tulle mesh knitted fabric with a course of 70C and a wale of 30W.

[0053] (Preparation) The obtained knitted fabric was subjected to a refining process and a heat shrinking (heat setting) process. Specifically, a refining process was carried out by washing off the oil agent attached to the yarn of the knitted fabric using an aqueous solution of a chemical containing 0.3% by mass of a soaping agent (Lipotol TC-350, manufactured by NICCA Chemical Co., Ltd.) and 0.1% by mass of a chelating agent (SJ Chelate A, manufactured by SEIREN SHOJI CO., LTD.) at a liquid temperature of 80°C and washing the knitted fabric. Next, a heat shrinking process was carried out at a temperature of 200°C for 1 minute with a course of 78C and a well of 20W.

[0054] (plating) The heat-shrunk fabric was then subjected to a lead chloride (PbCl 2 ) and tin chloride (SnCl 2 ), a catalyst for electroless plating was applied using a colloidal solution containing copper chloride (CuCl), and then electroless copper (Cu) plating and then electrolytic nickel (Ni) plating were carried out in succession to obtain the metal amounts shown in Table 1. 2 ), formaldehyde, and sodium hydroxide were used in the plating solution. 4 6H 2 O) and a plating solution containing sodium citrate was used.

[0055] In this way, the conductive cloth of Example 1 was obtained. A photograph of the conductive cloth of Example 1 is shown in Figure 1(a).

[0056] [Examples 2 to 4] Conductive cloths of Examples 2 to 4 were obtained in the same manner as in Example 1, except that the conditions were changed as shown in Table 1.

[0057] [Example 5] (Knitted Fabric Production) As shown in Table 2, a crimped yarn of polyethylene terephthalate filament (PET, 33 dtex / 6f) was used as the yarn, and a single Russell machine was used to obtain a marquisette knitted fabric with a course of 50C and a wale of 6W.

[0058] (Preparation) The obtained knitted fabric was subjected to refining and heat shrinking (heat setting) in the same manner as in Example 1. In the heat shrinking, the course was 52C and the welting was 6W.

[0059] (plating) Next, the heat-shrunk knitted fabric was plated in the same manner as in Example 1 by successively performing electroless copper (Cu) plating and then electrolytic nickel (Ni) plating to obtain the metal amounts shown in Table 2.

[0060] In this way, the conductive cloth of Example 5 was obtained. A photograph of the conductive cloth of Example 5 is shown in Figure 1(b).

[0061] [Examples 6 to 9] Conductive cloths of Examples 6 to 9 were obtained in the same manner as in Example 5, except that the conditions were changed as shown in Table 2.

[0062] [Comparative Example 1] (Knitted Fabric Production) As shown in Table 3, crimped yarn of polyethylene terephthalate filament (PET, 33 dtex / 12f) was used as the yarn, and a plain knit fabric with a plain knit structure, a course of 85C, and a wale of 60W was obtained using a circular knitting machine.

[0063] (Preparation) The obtained knitted fabric was subjected to refining and heat shrinking (heat setting) in the same manner as in Example 1. In the heat shrinking, the course was heat-shrunk at 90C and the welted at 42W.

[0064] (plating) Next, the heat-shrunk knitted fabric was plated in the same manner as in Example 1 by successively performing electroless copper (Cu) plating and then electrolytic nickel (Ni) plating to obtain the metal amounts shown in Table 3.

[0065] [Comparative Examples 2 to 4] (Knitted Fabric Production) 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.

[0066] (Preparation) The obtained knitted fabric was subjected to refining and heat shrinking (heat setting) in the same manner as in Example 1. In the heat shrinking, the heat shrinking was performed so as to obtain the courses and wells shown in Table 3.

[0067] (plating) Next, the heat-shrunk knitted fabric was plated in the same manner as in Example 1 by successively performing electroless copper (Cu) plating and then electrolytic nickel (Ni) plating to obtain the metal amounts shown in Table 3.

[0068] 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. In Table 2, the marquisette weaves of Examples 5 to 9 do not stretch in the warp and weft directions, so evaluations in these directions are not performed and are indicated as "-". In Table 3, the plain weave and half tricot weave of Comparative Example 1 do not have openings, so evaluations of the opening ratio ratio are not performed and are indicated as "-".

[0069] [Opening ratio] The surface of the conductive cloth was photographed at 50x magnification using a microscope (product name: Dino-Lite, manufactured by Anmo Electronics). The area of ​​the fibers and the area of ​​the openings in the obtained image were measured using image processing software (product name: Dino Capture 2.0, manufactured by Anmo Electronics), and the opening ratio was calculated according to the following formula (1). Opening rate (%) = (opening area) / (opening area + fiber area) × 100 (1) In this manner, the opening rate (S0) when not stretched and the opening rate (S1) when stretched by 20% were 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 was calculated. Note that the marquisette knitted fabrics of Examples 5 to 9 could not be pulled in the warp and weft directions, so the opening rate ratio (S1 / S0) was measured only in the diagonal direction. The plain knitted fabric of Comparative Example 1 and the half tricot knitted fabric of Comparative Example 2 did not have openings (opening rate (S0) was 0%), so the opening rate ratio (S1 / S0) was not measured.

[0070] [Tension at 20% elongation] The conductive cloth was cut in the warp direction, the weft direction, and the diagonal direction to obtain test pieces with a size of 2.5 cm wide x 15 cm long. The test pieces were set in the chucks of an autograph (product name: AG-IS, manufactured by Shimadzu Corporation) with a chuck distance of 10 cm, and cut by 100 mm in each direction shown in Tables 1 to 3. 2 The test piece was pulled at a speed of 100 / min, and the strength N was measured when the test piece was stretched by 20%. The measured value was divided by 2.5 cm to calculate the tension (N / cm) at 20% stretch. Note that, since the marquisette knitted structure of Examples 5 to 9 cannot be stretched in the warp and weft directions, the tension at 20% stretch was measured only in the diagonal direction.

[0071] [Stretch ratio of each side of the opening when stretched 20% to when not stretched (L1 / L0)] A test piece (width 2.5 cm x length 15 cm) obtained in the same manner as in the above [tension at 20% elongation] was photographed at 50 times magnification using a microscope in the same manner as in the above [opening ratio], and the length of each side in the obtained image was measured to measure the length of each side when not stretched (L0). Next, the test piece was pulled in the same manner as in the above [tension at 20% elongation], and the test piece when it was stretched by 20% was photographed in the same manner as in the above non-stretched state, and the length of each side in the obtained image was measured to obtain the length of each side when it was stretched by 20%. Then, the elongation ratio (L1 / L0) of each side of the opening when stretched by 20% relative to when it was not stretched was calculated. Note that the length of one of the opposing sides in the opening was the same as the length of the other side, so only the length of one of them was measured. That is, in the case of a tulle mesh knitted structure, the lengths of three sides were measured, and in the case of a marquisette knitted structure, the lengths of two sides were measured. In addition, the stretch ratio (L1 / L0) was measured only in the diagonal direction for the marquisette knitted fabrics of Examples 5 to 9, since they could not be stretched in the warp and weft directions. The stretch ratio (L1 / L0) was not measured for the plain knitted fabric of Comparative Example 1 and the half tricot knitted fabric of Comparative Example 2, since no openings were formed (opening ratio (S0) was 0%).

[0072] [Surface resistivity (Rs)] The surface resistivity (Rs) in the unstretched state was measured using a low resistivity meter (product name: Loresta MCP-T360, manufactured by Mitsubishi Chemical Corporation).

[0073] [Elongation rate E when resistance value changes by 50% compared to when not stretched] A copper foil tape was attached to the test piece (width 2.5 cm × length 15 cm) obtained in the same manner as in the above [Tension at 20% elongation] in the width direction so that the interval in the length direction was 10 cm. The test piece was set in the chuck of the above autograph with a gripping width of 12 cm, and the resistance value (Ω) between the copper foil tapes was measured using a tester while pulling the test piece, and the length of the test piece when the resistance value changed by 50% from before pulling (non-stretched, i.e., at the start of measurement) (W1, i.e., gripping width) was obtained. The ratio of the length when the resistance value changed by 50% to the length of the test piece when not stretched (W0, i.e., gripping width of 12 cm) was calculated as the elongation rate E (W1 / W0 × 100). Note that the marquisette knitting structure of Examples 5 to 9 cannot be pulled in the warp and weft directions, so the elongation rate E was measured only in the diagonal direction.

[0074] [Table 1]

[0075] [Table 2]

[0076] [Table 3]

[0077] As shown in Tables 1 and 2, the conductive cloths of Examples 1 to 4 had elongation rates E of 15% or more in all directions, warp, weft, and diagonal, in which the conductive cloths can be pulled, when the resistance value changed by 50% relative to when they were not stretched, and this indicated that the change in conductivity was suppressed when they were stretched.The conductive cloths of Examples 5 to 9 had elongation rates E of 15% or more in all diagonal directions in which the conductive cloths can be pulled, in which the resistance value changed by 50% relative to when they were not stretched, and this indicated that the change in conductivity was suppressed when they were stretched.

[0078] In contrast, as shown in Table 3, the conductive fabrics of Comparative Examples 1 to 4, which have no openings or have openings but whose structure is substantially stretchable, have an elongation rate E of less than 15% in at least two of the warp, weft, and diagonal directions when the resistance value changes by 50% compared to when not stretched, indicating that the change in conductivity during stretching is not suppressed. [Industrial Applicability]

[0079] The conductive cloth of the present invention can be suitably used, for example, as a sensor material, a monitoring material, a shielding material, and an electrode material.

Claims

1. A conductive cloth in which a base material formed by knitting or weaving a yarn is coated with a metal, The substrate has a substantially inextensible structure and an opening formed in the structure; The conductive cloth is configured such that when the substrate is pulled, the openings are deformed, thereby causing the substrate to stretch.

2. The conductive cloth according to claim 1, wherein the opening ratio of the substrate when unstretched is 40 to 95%.

3. 2. The conductive cloth according to claim 1, wherein the substrate has a tension of 10 N / cm or less at 20% elongation in at least one of the warp direction, weft direction, and diagonal direction.

4. 2. The conductive cloth according to claim 1, wherein the surface resistivity (Rs) of the substrate in the warp direction, weft direction and oblique direction when unstretched is 10 Ω / □ or less.

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

6. The conductive cloth according to any one of claims 1 to 5, wherein the substrate is a tulle mesh fabric or a marquisette fabric in which a part of the yarn forms a loop and another part of the yarn is inserted into the loop.

Images