CONDUCTIVE FABRIC

Abstract

A conductive fabric in which variation in conductivity is suppressed is provided. A conductive fabric including a substrate formed by braiding or weaving a yarn, said substrate being coated with a metal, wherein the substrate has a substantially non-extending tissue and an opening formed in said tissue, and wherein the substrate is configured to extend by deformation of the opening when said substrate is pulled.

Claims

1. A conductive fabric comprising a substrate formed by braiding or weaving a yarn, said substrate being coated with a metal, wherein: the substrate has a substantially non-extending tissue and an opening formed in said tissue, and wherein the substrate is configured to extend by deformation of the opening when said substrate is pulled.

2. The conductive fabric according to claim 1, wherein the substrate has an opening rate of 40-95% when not extended.

3. The conductive fabric according to claim 1, wherein an extension ratio of a side of the opening of the substantially non-extending tissue at 20% extension relative to the substrate when not extended is set to from 0.90 to 1.10.

4. The conductive fabric according to claim 1, wherein a tension at 20% extension in at least one or more of a longitudinal direction, a latitudinal direction and an oblique direction of the substrate is 10 N/cm or less.

5. The conductive fabric according to claim 1, wherein an elongation rate, which is a ratio of a length when the substrate is pulled so that a resistance value with respect to a length of the substrate when not extended varies by 50%, is 15% or more in all of the longitudinal direction, the latitudinal direction and the oblique direction.

6. The conductive fabric according to claim 1, wherein the substrate has a surface resistivity (Rs) when not extended of 10/ or less in all of the longitudinal direction, the latitudinal direction and the oblique direction.

7. The conductive fabric according to claim 1, wherein the opening has a minimum inner diameter when not extended or contracted of from 0.5 to 5 mm.

8. The conductive fabric according to claim 1, wherein the substrate is a tulle mesh knit or a marquisette knit in which a portion of the yarn forms a loop and another portion of the yarn is inserted into the loop.

9. The conductive fabric according to claim 1, which is used as a sensor material, a monitoring material, a shielding material or an electrode material.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0038] Each of FIGS. 1A and 1B is a photograph illustrating the conductive fabrics of Examples 1 and 5 of the present invention.

BEST MODE FOR CARRYING OUT INVENTION

[0039] Hereinafter, the conductive fabric of the present invention will be described. However, the present invention is not intended to be limited to the configurations described below or the examples described below.

<Conductive Fabric>

[0040] The conductive fabric of the present embodiment is a conductive fabric in which a substrate formed by braiding or weaving is coated with a metal. It is also possible to use a substrate formed by braiding or weaving a metal-coated yarn without any change as a conductive fabric.

(Substrate)

[0041] The substrate is formed by braiding or weaving a yarn. That is, the substrate is a knit or a woven fabric. Such substrate has a substantially non-extending tissue and an opening formed in said tissue, and is configured so that the substrate extends by deformation of the opening when the substrate is pulled.

[0042] Here, the tissue does not substantially extend is not limited to tissues that do not extend completely, and extension to a degree that does not affect the conductivity may be allowed. Specifically, the case where an extension ratio (L1/L0) of a length (L1, i.e., a length at 20% extension) of each side configuring the opening of the substrate when the substrate is extended by 20% in the longitudinal, latitudinal and diagonal directions to a length (L0) before extension (when not extended) of each side is in a range of from 0.90 to 1.10 (i.e., an extension ratio (L1/L0) of each side of the opening at 20% extension relative to when not extended is from 0.90 to 1.10), then the tissue is encompassed in that the tissue does not substantially extend. Incidentally, when the substrate is extended by 20%, some of the sides may extend and others may contract, and such aspect is also encompassed in that the tissue does not substantially extend. Furthermore, depending on the knitted tissue, the substrate may not be able to be pulled in either of the longitudinal direction, latitudinal direction and oblique direction. Such aspect is deemed that the tissue does not substantially extend in that direction.

[0043] Examples of the compositional raw material of the yarn include polyester fibers, polyamide fibers, polyethylene fibers, polyolefin fibers, polyurethane fibers, etc. Among these, polyester fibers and polyamide fibers are preferable. These fibers may be used alone or used as spun fibers or filament fibers of two or more kinds.

[0044] The fineness of the yarn is preferably from 15 to 85 dtex and more preferably from 20 to 60 dtex. By setting the fineness of the yarn to the above-mentioned range, the increase in the resistance value when not extended with respect to that when extended can be further suppressed while increasing the strength of the conductive fabric.

[0045] The number of the filaments in the yarn is preferably from 2 to 40 f (pieces), and more preferably from 6 to 36 f (pieces). By setting the number of the filaments of the yarn to the above-mentioned range, an increase in the resistance value when not extended with respect to that when extended can be further suppressed while increasing the strength of the conductive fabric.

[0046] As the yarn, raw silk yarns, crimped yarns, etc. can be used. Among these, crimped yarns are preferred. When a crimped yarn is to be adopted as the yarn, by applying heat shrinkage, the crimped yarn shrinks, the loops of the knitted tissue are tightened, and the extension of each side of the opening of the conductive fabric is suppressed.

[0047] In the case when the substrate is a knit, such substrate can be knitted by a tricot knitting machine, a Russell knitting machine, a circular knitting machine, etc. Among these, it is preferable that the substrate is knitted by a tricot knitting machine or a Russell knitting machine in that the opening can be enlarged. The shape of the opening includes a circular (e.g., circle, ellipse) shape, a triangular shape, a quadrangular shape, a pentagonal shape, a hexagonal shape (honeycomb structure), etc. The substrate is preferably a knit in which a portion of the yarn forms a loop and another portion of the yarn (insertion yarn) is inserted into the loop, preferably a tulle mesh knit, which has hexagonal-shaped openings or a marquisette knit, which has square-shaped openings.

[0048] The tulle mesh knit can extend in any direction 360 by deformation of the opening. That is, it can be extended to an angle other than the longitudinal direction or the latitudinal direction (an angle intersected with the longitudinal direction or the latitudinal direction) of said knit. In addition to being able to extend in this way, there is a little change in the resistance value when extended relative to that when not extended. The marquisette knit can be extended in an oblique direction in accordance with deformation of the opening. By heat shrinking these tulle mesh knit and marquisette knit, the loops of the knitted tissue are tightened, and the areas other than the opening of the conductive fabric are more suppressed in extension. This results in more suppression of the change in the intersection position (contact) of the yarns in accordance with the extension, and more suppression of the damage to the metal coating with the extension. In this way, by selecting the tulle mesh knit or the marquisette knit as the substrate, the variation in the conductivity of said conductive fabric is further suppressed. Furthermore, by selecting the tulle mesh knit or the marquisette knit, the opening can be enlarged, and thus the amount of the metal coating can be reduced.

[0049] The yarn is preferably one that does not extend or contract substantially. Specifically, it is preferable that the yarn is such that an extension ratio (L1/L0) of each side of the opening at 20% extension relative to that when not extended satisfies from 0.90 to 1.10 in the longitudinal, latitudinal and diagonal directions as described above. Such yarn can be obtained by applying heat shrinkage to the substrate. Since the conductive fabric is extended more only by deformation of the opening, variation in conductivity is further suppressed.

[0050] As described above, when applying heat shrinkage to the substrate, the heating temperature and pressure may be appropriately set to conditions such that the yarn does not substantially extend, the yarn can tighten the loop, and the yarn is not damaged.

[0051] The opening, when not extended or contracted, preferably has a minimum inner diameter of from 0.5 to 5 mm. The minimum inner diameter of the opening is the diameter of the circle that is inscribed into the opening. By setting the minimum inner diameter of the opening when not extended or contracted to the above-mentioned range, the degree of extension of said conductive fabric can be made more appropriate.

[0052] The basis weight of the substrate is preferably from 1 to 50 g/m.sup.2, and more preferably from 6 to 42 g/m.sup.2. By setting the basis weight of the substrate to the above-mentioned range, the amount of the metal coating covering the substrate can be made appropriate while making the strength of the substrate appropriate. In the case where the substrate is heat shrinkable, the above-mentioned basis weight is a basis weight after the heat shrinkage.

[0053] It is preferable that the substrate has an opening rate (S0) when not extended of from 40 to 95%. As described above, the degree of deformation of the opening corresponds to the degree of extension of the conductive fabric. By setting the opening rate of the substrate when not extended to the above-mentioned range, the degree of extension of said conductive fabric can be more appropriate, and thus the variation in conductivity of said conductive fabric is further suppressed. Furthermore, the amount of the metal coating can be relatively reduced.

(Metal Coating)

[0054] Examples of the metal that constitutes the metal coating include gold, silver, copper, platinum, nickel, zinc, tin, etc. One kind of metal may be used alone, or two or more kinds of metals may be used. When two or more metals are used, they may be used by dividing into multiple layers, or they may be an alloy containing multiple metals. Among these, the metal is preferably copper or nickel, and a metal coating on which a nickel coating is laminated on a copper coating is more preferable.

[0055] The amount of the metal in the metal coating is preferably from 2 to 30 g/m.sup.2. Furthermore, when a metal coating is laminated with nickel on copper, the amount of the copper is preferably 1.5 to 28 g/m.sup.2, and the amount of the nickel is preferably 0.3 to 5 g/m.sup.2. By setting the metal amount to the above-mentioned range, the conductivity of the conductive fabric can be made more appropriate while making the flexibility more appropriate.

[0056] The thickness of the metal coating is preferably from 0.5 to 2 m. By setting the thickness of the metal coating to the above-mentioned range, the conductivity of the conductive fabric can be made more appropriate while making the flexibility more appropriate.

[0057] The method for forming the metal coating includes methods such as vapor deposition, sputtering, electroplating, electroless plating, etc. Among these, electroless plating and/or electroplating are preferred in that a more uniform metal coating can be formed in all directions of the surface of the substrate. Furthermore, the metal film is preferably made into a multilayer structure by first applying electroless plating to the substrate, and then electroplating, and it is more preferable to apply electro-nickel plating after applying electroless copper plating.

[0058] When performing electroless copper plating and electro-nickel plating, a catalyst for electroless plating may first be applied to the substrate in a colloidal solution containing lead chloride (PbCl.sub.2) and tin chloride (SnCl.sub.2), thereafter electroless copper plating, then electro-nickel plating may be sequentially performed. In electroless copper plating, a plating solution containing copper chloride (CuCl.sub.2), formaldehyde and sodium hydroxide may be used. In electro-nickel plating, a plating solution containing nickel sulfate hexahydrate (NiSO.sub.4.Math.6H.sub.2O) and sodium citrate may be used.

(Characteristics of Conductive Fabric)

[0059] It is preferable that a ratio (S1/S0) of an opening rate (S1) at 20% extension to an opening rate (S0) when not extended of the substrate (i.e., the conductive fabric) is from 0.5 to 1 in either of the longitudinal direction, the latitudinal direction and the diagonal direction. By setting the ratio (S1/S0) to be in the above-mentioned range, the degree of deformation of the opening in accordance with the extension can be made more appropriate.

[0060] The tension at 20% extension in at least one of the longitudinal direction, the latitudinal direction and the oblique direction of the substrate is preferably 10 N/cm or less. By setting the tension at 20% extension in at least one or more of a longitudinal direction, a latitudinal direction and an oblique direction of the substrate to the above-mentioned range, the opening can be deformed with a lesser load. As a result, it is not necessary to apply an excessive load to extend said conductive fabric, and thus damages to the metal coating can be further suppressed.

[0061] An elongation rate E (W1/W0100), which is a ratio of a length (W1) when the substrate is pulled so that a resistance value with respect to a length (W0) of the substrate when not extended varies by 50%, is preferably 15% or more in all of the longitudinal direction, the latitudinal direction and the oblique direction. That is, the elongation E when the resistance value with respect to that when not extended varies by 50% is preferably 15% or more in all of the longitudinal direction, the latitudinal direction and the oblique direction. By setting the elongation rate E to the above-mentioned range, variation in the resistance value when extended with respect to that when not extended can be further suppressed. Furthermore, depending on the knitted tissue, the substrate may not be able to be pulled in either of the longitudinal direction, latitudinal direction and oblique direction. In such a case, there shall be no variation in resistance value in the direction to which the substrate cannot be pulled.

[0062] It is preferable that the surface resistivity (Rs) of the substrate when not extended in all of the longitudinal direction, the latitudinal direction and the oblique direction is 10/ or less. Here, the unit of surface resistivity (Rs) / means ohm per square (surface resistance value per unit area (1 cm.sup.2)). By setting all of the surface resistivity (Rs) of the substrate when not extended in the longitudinal direction, the latitudinal direction and the oblique direction to be in the above-mentioned range, variation in the resistance value when not extended with respect to when the substrate is extended can be further suppressed.

Preparation of Conductive Fabric

[0063] The conductive fabric of the present embodiment is obtained, for example, as follows.

Preparation of Substrate

[0064] A knitting machine or weaving machine is used to knit or weave a yarn to obtain a knit or textile (a substrate) having a desired knitted tissue or woven tissue.

Pre-Processing

[0065] Refining processing and heat shrink (heat set) processing are performed on the obtained substrate. Specifically, first, a refining step is performed to wash the substrate by using a predetermined aqueous agent solution, setting liquid temperature conditions appropriately, and washing off an oil adhering to a yarn of the substrate. The heat shrink process is then performed for a predetermined time at a predetermined temperature so as to give desired course and well.

Plating Processing

[0066] A catalyst for electroless plating is then applied to the heat-shrunk substrate in a predetermined colloidal solution, and plating processing is then performed. For example, electroless plating, and then electroplating are sequentially performed.

[0067] In this way, a conductive fabric can be obtained.

Applications of Conductive Fabric

[0068] Although the applications of the conductive fabric are not particularly limited, it can be utilized as sensor materials for touch sensors, etc., monitoring materials for monitoring systems, etc., shielding materials, electrode materials, etc.

EXAMPLES

Example 1

(Preparation of Knit)

[0069] As shown in Table 1, a crimped yarn of polyethylene terephthalate filaments (PET, 33 dtex/12f) was used as a yarn, and a single tricot machine was used to obtain a tulle mesh knit having a tulle mesh knit tissue with a course of 70 C and a well of 30 W.

(Pre-Processing)

[0070] The obtained knit was subjected to refining processing and heat shrink (heat set) processing. Specifically, first, a refining step for washing the knit was performed by using an aqueous agent solution 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.), setting a liquid temperature condition to 80 C., and washing off an oil agent adhering to the yarn of the knit. The heat shrink process was then performed for 1 minute at a temperature of 200 C. so that the knit had a course of 78 C and a well of 20 W.

(Plating Processing)

[0071] A catalyst for electroless plating was then applied to the heat-shrunk knit in a colloidal solution containing lead chloride (PbCl.sub.2) and tin chloride (SnCl.sub.2), electroless copper (Cu) plating, and electro-nickel (Ni) plating were sequentially performed to achieve the metal amount shown in Table 1. In the electroless copper plating, a plating solution containing copper chloride (CuCl.sub.2), formaldehyde and sodium hydroxide was used. In the electro-nickel plating, a plating solution containing nickel sulfate hexahydrate (NiSO.sub.4.Math.6H.sub.2O) and sodium citrate was used.

[0072] In this way, the conductive fabric of Example 1 was obtained. A photograph of the conductive fabric of said Example 1 is shown in FIG. 1A.

Examples 2-4

[0073] The conductive fabrics of Examples 2-4 were obtained in a similar manner to that of Example 1, except that the conditions were changed to that shown in Table 1.

Example 5

(Preparation of Knit)

[0074] As shown in Table 2, a crimped yarn of polyethylene terephthalate filaments (PET, 33 dtex/6f) was used as a yarn, and a single Russell machine was used to obtain a marquisette knit having a marquisette knit tissue with a course of 50 C and a well of 6 W.

(Pre-Processing)

[0075] The obtained knit was subjected to refining processing and heat shrink (heat set) processing in a manner similar to that of Example 1. In the heat shrink process, the heat shrinking was performed so that the knit had a course of 52 C and a well of 6 W.

(Plating Processing)

[0076] Plating processing was performed by sequentially performing electroless copper (Cu) plating and then electro-nickel (Ni) plating on the heat-shrunk knit in a similar manner to that in Example 1 to achieve the metal amount shown in Table 2.

[0077] In this way, the conductive fabric of Example 5 was obtained. A photograph of the conductive fabric of said Example 5 is shown in FIG. 1B.

Examples 6-9

[0078] The conductive fabrics of Examples 6-9 were obtained in a similar manner to that of Example 5, except that the conditions were changed to that shown in Table 2.

Comparative Example 1

(Preparation of Knit)

[0079] As shown in Table 3, a crimped yarn of polyethylene terephthalate filaments (PET, 33 dtex/12f) was used as a yarn, and a round knitting machine was used to obtain a plain knit having a plain knit tissue with a course of 85 C and a well of 60 W.

(Pre-Processing)

[0080] The obtained knit was subjected to refining processing and heat shrink (heat set) processing in a manner similar to that of Example 1. In the heat shrink process, the heat shrink process was performed so that the knit had a course of 90 C and a well of 42 W.

(Plating Processing)

[0081] Plating processing was then performed so as to give the metal amount shown in Table 3 by sequentially performing electroless copper (Cu) plating and then electro-nickel (Ni) plating on the heat-shrunk knit in a similar manner to that in Example 1.

Comparative Examples 2-4

(Preparation of Knit)

[0082] As shown in Table 3, a crimped yarn of polyethylene terephthalate filaments (PET, 33 dtex/12f) was used as a yarn, and a knitting machine shown in Table 3 was used to obtain the knit shown in Table 3 with the knit tissue shown in Table 3.

(Pre-Processing)

[0083] The obtained knit was subjected to refining processing and heat shrink (heat set) processing in a manner similar to that of Example 1. In the heat shrink process, the heat shrink process was performed so as to have the course and well shown in Table 3.

(Plating Processing)

[0084] Plating processing was performed so as to give the metal amount shown in Table 3 by sequentially performing electroless copper (Cu) plating and then electro-nickel (Ni) plating on the heat-shrunk knit in a similar manner to that in Example 1.

[0085] The conductive fabrics of Examples 1-9 and Comparative Examples 1-4 were evaluated as follows. The results are shown in Tables 1-3. Incidentally, in Table 2, the marquisette tissues of Examples 5 to 9 do not extend in the longitudinal and latitudinal directions, so these directions are not evaluated and are denoted as . In Table 3, since the plain tissue and half-tricot tissue in Comparative Example 1 do not have openings, the opening ratios are not evaluated, and are denoted as .

[Opening Rate]

[0086] The surface of the conductive fabric was photographed at 50 using a microscope (product name: Dino-Lite, manufactured by AnMo Electronics). For the obtained image, the area of the fibers in the image and the area of the opening were measured using image processing software (product name: Dino Capture 2.0, manufactured by AnMoElectronics), and the opening rate was calculated according to the following equation (1).

[00001]$\begin{array}{cc}\mathrm{Opening}\mathrm{rate}\left(\%\right)=\left(\mathrm{Area}\mathrm{of}\mathrm{opening}\right)/\left(\mathrm{Area}\mathrm{of}\mathrm{opening}+\mathrm{Area}\mathrm{of}\mathrm{fibers}\right)100& \left(1\right)\end{array}$

[0087] In this way, in each of the directions shown in Tables 1-3, an opening rate (S0) when not extended and an opening rate (S1) at 20% extension were measured, and a ratio (S1/S) of the opening rate (S1) at 20% extension to the opening rate (S0) when not extended was calculated. Incidentally, since it was impossible to pull the marquisette tissues of Examples 5 to 9 in the longitudinal and latitudinal directions, the ratio (S1/S0) of the opening rates was measured only for the diagonal direction. Since openings were not formed (the opening rate (S0) was 0%) in the plain tissue of Comparative Example 1 and the half-tricot tissue of Comparative Example 2, the ratio (S1/S0) of the opening rates was not measured.

[Tension at 20% Extension]

[0088] The conductive fabric was cut in the longitudinal direction, the latitudinal direction and the oblique direction so as to have a size with a width of 2.5 cm and a length of 15 cm, respectively, to obtain a test specimen. The test specimen was set into chucks of an autograph (product name: AG-IS, manufactured by Shimadzu Corporation) at a distance between chucks of 10 cm, pulled in each of the directions shown in Tables 1-3 at a speed of 100 mm.sup.2/min, and the strength N when the test specimen was extended by 20% was measured. The tension at 20% extension (N/cm) was calculated by dividing the measured value by 2.5 cm. Incidentally, since it was impossible to pull the marquisette tissues of Examples 5 to 9 in the longitudinal and latitudinal directions, the tension at 20% extension was measured only for the diagonal direction.

[Extension Ratio (L1/L0) of Each Side of Opening at 20% Extension Relative to when not Extended]

[0089] A test specimen (width: 2.5 cmlength: 15 cm) obtained in a similar manner to that mentioned in the above-mentioned [Tension at 20% extension] was photographed at a factor of 50 using a microscope in the same manner as the above-mentioned [Opening rate], and the length of each side in the obtained image was measured to measure the length of each side (L0) when not extended. The test specimen was then pulled in a similar manner to that mentioned in the above-mentioned [Tension at 20% extension], and the test specimen when the test specimen was extended by 20% was photographed in a similar manner to that of the test specimen when not extended, and the length of each side in the obtained image was measured to obtain the length of each side at 20% extension. Then, an extension ratio (L1/L0) of each side of the opening at 20% extension with respect to when not extended was calculated. Incidentally, since the length of one of the opposing sides in the opening is the same as the length of the other side, only one of the lengths was measured. That is, the lengths of three sides were measured in the case of a tulle mesh knitted tissue, and the lengths of two sides were measured in the case of a marquisette knitted tissue. Incidentally, since it was impossible to pull the marquisette tissues of Examples 5 to 9 in the longitudinal and latitudinal directions, the extension ratio (L1/L0) was measured only for the diagonal direction. Since the plain tissue of Comparative Example 1 and the half-tricot tissue of Comparative Example 2 did not form an opening (the opening rate (S0) was 0%), the extension ratio (L1/L0) was not measured.

[Surface Resistivity (Rs)]

[0090] The surface resistivity (Rs) when not extended was measured by a low-resistivity meter (product name: Loresta MCP-T360, manufactured by Mitsubishi Chemical Corporation).

[Elongation E when Resistance Value with Respect to that when not Extended Varies by 50%]

[0091] Copper foil tapes were attached to a test specimen (width: 2.5 cmlength: 15 cm) obtained in a similar manner to that mentioned in the above-mentioned [Tension at 20% extension] in the width direction so that the gaps in the lengthwise direction became 10 cm. The test specimen was set on the chuck of the above-mentioned autograph at a gripping width of 12 cm, and a resistance value () between the copper foil tapes was measured using a tester while pulling the test specimen, and the length of the test specimen (W1, that is, a gripping width) when the resistance value varied by 50% from that before pulling (when not extended, that is, at the start of the measurement) was obtained. Then, the ratio of the length when the resistance value varies by 50% with respect to the length of the test specimen (W0, that is, 12 cm, which is the grip width) when the length of the test specimen when not extended was calculated as the extension rate E (W1/W0100). Incidentally, since it was impossible to pull the marquisette tissues of Examples 5 to 9 in the longitudinal and latitudinal directions, the extension rate E was measured only for the diagonal direction.

TABLE-US-00001 TABLE 1 Example 1 Example 2 Example 3 Example 4 Substrate Yarn Material PET PET PET PET Fineness (dtex) 33 33 16 84 Number of filaments 12f 12f 6f 36f Process Crimped yarn Raw silk yarn Crimped yarn Crimped yarn Knit Knitting Machine Tricot machine Tricot machine Tricot machine Tricot machine Gauge 28G 28G 28G 28G Name of knitted tissue Tulle mesh Tulle mesh Tulle mesh Tulle mesh Braided yarn tissue Insertion yarn Insertion yarn Insertion yarn Insertion yarn Loop yarn Loop yarn Loop yarn Loop yarn Knit after Basis weight (g/m.sup.2) 18 18 12 42 heat Characteristic Course 78C 78C 80C 70C shrinkage Well 20W 20W 20W 20W Metal Metal Cu (g/m.sup.2) 9.2 9.0 6.6 21.0 Coating amount Ni (g/m.sup.2) 1.6 1.5 1.3 2.2 Total (g/m.sup.2) 10.8 10.5 7.9 23.2 Opening Presence or absence of Present Present Present Present opening Minimum inner diameter 0.9 0.9 1.0 0.7 of opening (mm) Opening ratio S0 (%) 69 71 74 54 Ratio (S1/S0) of opening Longitudinal 0.73 0.75 0.76 0.67 rates at 20% extension Transversal 0.75 0.76 0.73 0.64 with respect to that Oblique 0.73 0.77 0.75 0.64 when not extended Tension at 20% extension Longitudinal (N/cm) 4.3 4.1 3.8 7.7 Transversal (N/cm) 2.4 2.4 2.2 6.7 Oblique (N/cm) 3.7 3.6 3.3 6.9 Extension ratio (L1/L0) Longitudinal Side 1 1.01 1.02 1.03 1.01 of each side of opening Side 2 0.97 0.98 1.00 0.96 at 20% extension with Side 3 0.96 0.97 0.98 0.96 respect to when not Transversal Side 1 0.98 0.98 0.97 0.98 extended Side 2 1.01 1.02 1.01 1.02 Side 3 1.04 1.03 1.03 1.03 Oblique Side 1 0.95 0.97 0.96 0.95 Side 2 1.04 1.02 1.03 1.02 Side 3 1.02 1.01 1.03 1.02 Surface resistivity Rs Longitudinal (/) 0.0509 0.0515 0.0432 0.0355 when not extended Transversal (/) 0.0567 0.0555 0.0405 0.0385 Oblique (/) 0.0524 0.0533 0.0454 0.0347 Elongation rate E when Longitudinal (%) 30 33 35 33 resistance value varies Transversal (%) 32 35 32 34 by 50% with respect to Oblique (%) 35 35 33 35 that when not extended

TABLE-US-00002 TABLE 2 Example 5 Example 6 Example 7 Example 8 Example 9 Substrate Yarn Material PET PET PET PET PET Fineness (dtex) 33 33 33 16 84 Number of filaments 6f 6f 6f 6f 36f Process Crimped Raw silk Crimped Crimped Crimped yarn yarn yarn yarn yarn Knit Knitting Machine Russell Russell Russell Russell Russell machine machine machine machine machine Gauge 6G 6G 12G 6G 6G Name of knitted tissue Marquisette Marquisette Marquisette Marquisette Marquisette Braided yarn tissue Insertion Insertion Insertion Insertion Insertion yarn yarn yarn yarn yarn Loop yarn Loop yarn Loop yarn Loop yarn Loop yarn Knit after Basis weight (g/m.sup.2) 8 8 16 6 22 heat Characteristic Course 52C 52C 50C 52C 40C shrinkage Well 6W 6W 12W 6W 6W Metal Metal Cu (g/m.sup.2) 2.5 2.5 5.0 2.0 21.0 Coating amount Ni (g/m.sup.2) 0.5 0.5 1.0 0.4 2.2 Total (g/m.sup.2) 3.0 3.0 6.0 2.4 23.2 Opening Presence or absence of Present Present Present Present Present opening Minimum inner diameter 4.2 4.2 2.0 4.3 4.1 of opening (mm) Opening ratio S0 (%) 90 92 81 93 88 Ratio (S1/S0) of opening Longitudinal rates at 20% extension Transversal with respect to that Oblique 0.93 0.95 0.88 0.93 0.86 when not extended Tension at 20% extension Longitudinal (N/cm) Transversal (N/cm) Oblique (N/cm) 0.1 0.1 0.1 0.1 0.1 Extension ratio (L1/L0) Longitudinal Side 1 of each side of opening Side 2 at 20% extension with Side 3 respect to when not Transversal Side 1 extended Side 2 Side 3 Oblique Side 1 1.01 1.00 1.01 1.00 1.01 Side 2 0.98 0.99 0.98 0.99 0.98 Side 3 Surface resistivity Rs Longitudinal (/) 0.2850 0.2590 0.2020 0.2950 0.1530 when not extended Transversal (/) 0.2770 0.2330 0.1970 0.3030 0.1750 Oblique (/) 0.2640 0.2440 0.2000 0.3110 0.1650 Elongation rate E when Longitudinal (%) resistance value varies Transversal (%) by 50% with respect to Oblique (%) 39 37 43 35 43 that when not extended

TABLE-US-00003 TABLE 3 Comparative Comparative Comparative Comparative Example 1 Example 2 Example 3 Example 4 Substrate Yarn Material PET PET PET PET Fineness (dtex) 33 33 22 33 Number of filaments 12f 12f 12f 12f Process Crimped yarn Crimped yarn Crimped yarn Crimped yarn Knit Knitting Machine Round knitting Tricot machine Tricot machine Tricot machine machine Gauge 44G 28G 14G 7G Name of knitted tissue Plain Half- 4c mesh 8c mesh tricot Braided yarn tissue Loop yarn Loop yarn Loop yarn Loop yarn Loop yarn Loop yarn Loop yarn Loop yarn Knit after Basis weight (g/m.sup.2) 30 41 20 10 heat Characteristic Course 90C 55C 70C 70C shrinkage Well 42W 30W 14W 7W Metal Metal Cu (g/m.sup.2) 27.5 41.1 30.0 13.3 Coating amount Ni (g/m.sup.2) 2.1 3.0 2.8 1.9 Total (g/m.sup.2) 29.6 44.1 32.8 15.2 Opening Presence or absence of Absent Absent Present Present opening Minimum inner diameter 0 0 0.9 2.1 of opening (mm) Opening ratio S0 (%) 0 0 45 82 Ratio (S1/S0) of opening Longitudinal 0.78 0.93 rates at 20% extension Transversal 0.75 0.92 with respect to that Oblique 0.78 0.93 when not extended Tension at 20% extension Longitudinal (N/cm) 6.2 8.4 3.6 0.3 Transversal (N/cm) 1.1 7.5 3.3 0.4 Oblique (N/cm) 4.6 8.0 3.6 0.4 Extension ratio (L1/L0) Longitudinal Side 1 0.78 0.76 of each side of opening Side 2 0.82 0.83 at 20% extension with Side 3 respect to when not Transversal Side 1 0.94 0.96 extended Side 2 1.11 1.09 Side 3 Oblique Side 1 1.19 1.21 Side 2 0.82 0.80 Side 3 Surface resistivity Rs Longitudinal (/) 0.0342 0.0366 0.0566 0.1990 when not extended Transversal (/) 0.0322 0.0384 0.0515 0.2010 Oblique (/) 0.0311 0.0365 0.0519 0.1750 Elongation rate E when Longitudinal (%) 2 6 11 12 resistance value varies Transversal (%) 55 40 5 4 by 50% with respect to Oblique (%) 2 3 5 3 that when not extended

[0092] As shown in Tables 1-2, the conductive fabrics of Examples 1-4 showed that the elongation rate E when the resistance value with respect to that when not extended varies by 50% is 15% or more in all of the longitudinal direction, the latitudinal direction and the oblique direction in which it was possible to pull these conductive fabrics, and thus it was shown that the variation in conductivity was suppressed during the extension. The conductive fabrics of Examples 5-9 showed that the elongation rate E when the resistance value with respect to that when not extended varies by 50% was 15% or more in the oblique direction in which it was possible to pull these conductive fabrics, and thus the variation in conductivity was suppressed during extension.

[0093] In contrast, as shown in Table 3, the conductive fabrics of Comparative Examples 1-4, where the tissue substantially extends even without or with an opening, showed that the elongation rate E when the resistance value with respect to when not extended varies by 50% was less than 15% in at least two or more of the longitudinal direction, the latitudinal direction and the oblique direction, and thus the variation in conductivity was not suppressed during extension.

INDUSTRIAL APPLICABILITY

[0094] The conductive fabric of the present invention can be preferably used for, for example, sensor materials, monitoring materials, shielding materials, and electrode materials.