Textile and cable covers for robot arms

Abstract

In order to provide a fabric that has low frictional properties and can exhibit long-term slidability even after receiving high-speed frictional force under high load, this fabric is characterized in that a composite yarn of fluorine resin fibers A and fibers B other than fluorine resin fibers is used as at least a warp yarn or a weft yarn, the mass ratio α of the fluorine resin fibers A in the composite yarn is 5–70%, and the ratio of the area proportion X of the fluorine resin fibers at the surface of the fabric to the mass ratio Y of the fluorine resin fibers in the fabric is at least 1 and no more than 5. This fabric can be usefully used in a cable cover for a robot arm.

Description

[Technical Field]

[0001] The present invention relates to a wear-resistant fabric and a cable cover for a robot arm. [Background technology]

[0002] Taking advantage of the low coefficient of friction of fluororesin, sliding fabrics have been developed that improve friction durability by forming fluororesin into fibers and arranging them on the surface of sliding components as woven or nonwoven fabrics. Furthermore, because fluororesin fibers generally have low strength, a technique has been disclosed that improves sliding durability by interweaving fluororesin fibers with fibers stronger than the fluororesin fibers. Examples of the interweaving technique include a double-layered fabric in which fluororesin fibers are arranged on the sliding surface and fibers other than fluororesin fibers are arranged on the non-sliding surface, and a fabric made of composite yarns formed from fluororesin fibers and fibers other than fluororesin fibers.

[0003] For example, Patent Document 1 discloses a heat- and wear-resistant multilayer fabric comprising a sliding fabric containing fluororesin fibers and a base fabric, the base surface of which has an optimal configuration, resulting in high heat resistance and wear resistance and long-term sliding properties even when exposed to high-temperature environments. PTFE worn away by sliding is received at the entanglement bonding points (bonding points due to entanglement) between the sliding fabric and the base fabric and at the sliding surface side of the base fabric, with some PTFE coating the entanglement bonding points and the sliding fabric side surface of the base fabric, and the remaining PTFE accumulates in the uneven parts of the base fabric. Even when the entire multilayer fabric wears away, the PTFE accumulated in the uneven parts of the base fabric continues to coat the base fabric surface, resulting in a continuous PTFE-coated fabric surface, and the fabric surface is shown to maintain long-term sliding properties.

[0004] Patent Document 2 discloses a self-lubricating fabric that is a woven fabric containing a composite yarn formed from a fluororesin fiber and another fiber, in which the surface area of ​​the other fiber on one side of the fabric accounts for 0 to 30% of the surface area of ​​the entire composite yarn. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6398189 [Patent Document 2] International Publication No. 2017 / 020821 Summary of the Invention [Problem to be solved by the invention]

[0006] The fabric described in Patent Document 1 was a double-layered fabric in which the PTFE fiber and the other fiber were separately arranged in a sliding fabric layer and a base fabric layer, respectively. Therefore, when exposed to high-speed sliding under a high load, the fluororesin fiber was easily expelled, and there was a problem that sufficient long-term sliding durability could not be obtained.

[0007] The self-lubricating fabric described in Patent Document 2 uses a composite yarn made of a fluororesin fiber and other fibers, which makes it easy for fluorine wear particles to transfer to the other fibers adjacent to the fluororesin fiber, thereby improving sliding durability under high loads. However, because the ratio of fluororesin fiber in the composite yarn was made excessively high compared to the other fibers in order to achieve low friction, the discharge of wear particles from the fluororesin yarn could not be sufficiently suppressed when exposed to high-speed sliding under high loads, leaving room for improvement in long-term sliding durability.

[0008] Therefore, an object of the present invention is to provide a woven fabric that has low friction and can exhibit long-term sliding properties even when subjected to high-speed frictional force under a heavy load. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention has the following configuration.

[0010] A woven fabric using a composite yarn of a fluororesin fiber A and a fiber B other than a fluororesin fiber as at least one of the warp and weft, wherein the mass ratio α of the fluororesin fiber A in the composite yarn is 5 to 70%, and the ratio X / Y of the area ratio X of the fluororesin fiber on the surface of the woven fabric to the mass ratio Y of the fluororesin fiber in the woven fabric is 1 or more and 5 or less.

[0011] A composite yarn is used for either the warp or weft, and the composite yarn is directly Exchange The woven fabric is formed by using fiber B as either a weft or a warp.

[0012] The woven fabric, wherein the area ratio X is 10% or more and 60% or less.

[0013] The woven fabric, wherein the composite yarn is a plied yarn obtained by pliedly twisting a fluororesin fiber A and a fiber B other than a fluororesin fiber.

[0014] The woven fabric, wherein fiber B constituting the doubled and twisted yarn is a twisted yarn.

[0015] The woven fabric, wherein the fluororesin fiber A is made of polytetrafluoroethylene resin.

[0016] The woven fabric, wherein the fiber B is a fiber having a tensile strength of 7 cN / dtex or more.

[0017] The woven fabric, wherein the fiber B has a tensile strength of 15 to 50 cN / dtex.

[0018] The woven fabric, wherein the fiber B is a fiber having a heat resistance temperature of 280°C or higher.

[0019] The above woven fabric, wherein the fiber B is a fiber having a tensile modulus of elasticity of 450 to 800 cN / dtex.

[0020] The woven fabric, wherein the fiber B is an organic fiber.

[0021] The woven fabric, wherein the fiber B is a fiber selected from the group consisting of a liquid crystal polyester fiber, a para-aramid fiber, and a polyparaphenylene benzobisoxazole fiber.

[0022] A cable cover for a robot arm, at least part of which uses the above-mentioned woven fabric. [Effects of the Invention]

[0023] According to the present invention, there is provided a woven fabric which has low friction and can exhibit long-term sliding properties even when subjected to high-speed frictional force under a high load. DETAILED DESCRIPTION OF THE INVENTION

[0024] The woven fabric according to the present invention uses a composite yarn of fluororesin fiber A and a fiber B other than fluororesin fiber as at least one of the warp and weft yarns, and is characterized in that the mass ratio α of fluororesin fiber A in the composite yarn is 5 to 70%, and the ratio of the area ratio X of fluororesin fiber A on the surface of the fabric to the mass ratio Y of fluororesin fiber A in the woven fabric is 1 to 5. By arranging the fluororesin fiber in the woven fabric as a composite yarn with a fiber other than fluororesin fiber, the fluororesin fiber and fiber B are adjacent to each other in the woven fabric, facilitating the transfer of fluorine wear powder generated by wear of fluororesin fiber A due to sliding to fiber B, forming a self-lubricating film, thereby achieving excellent wear resistance under high loads. Furthermore, for high-speed sliding under high loads, the mass ratio of the fluororesin fiber in the composite yarn, the area ratio of the fluororesin fiber, and the mass ratio of the fluororesin fiber in the woven fabric can be optimized, with the fiber other than fluororesin fiber acting as a skeletal fiber to support the fabric, ensuring long-term sliding performance even when subjected to high-speed friction under high loads.

[0025] The woven fabric of the present invention uses a composite yarn of fluororesin fiber A and fiber B other than fluororesin fiber as at least one of the warp and weft. More preferably, the composite yarn is used as either the warp or weft, and the composite yarn is OrthogonalFiber B is used for either the weft or warp yarns. By using such a configuration, it is possible to more easily obtain a woven fabric with an appropriate value for X / Y, which will be described later. Furthermore, a particularly preferred embodiment is one in which the warp yarn is a composite yarn and the weft yarn is fiber B. Generally, the crimp of a woven yarn is large in the warp yarn and small in the weft yarn, so by using such a configuration, the composite yarn containing fluororesin fiber A is easily exposed on the surface of the fabric, and fiber B is arranged linearly in the woven fabric, improving the strength utilization efficiency of fiber B. Note that, when the crimp of the weft yarn is larger than that of the warp yarn, it is also a preferred embodiment to use fiber B for the warp yarn and composite yarn for the weft yarn. When a composite yarn is used for either the warp or weft yarn, the composite yarn Orthogonal It is preferable that the weft or warp yarn used in the composite yarn is the same type of fiber as fiber B. The same type of fiber here means fibers made of the same polymer, and the number of filaments and fineness do not have to be the same. The same polymer here means that the polymers constituting the fibers are substantially the same, and the presence or absence of additives and the type of additives added may be different. Furthermore, "substantially the same" does not necessarily mean that the fibers are strictly the same, and may be a combination of a homopolymer and a copolymer, or a copolymer and another copolymer, as long as the main repeating unit is the same and the resulting woven fabric does not significantly impair the anisotropy of wrinkle formation and sliding durability described below. For composite yarns Orthogonal By using the same type of fiber as fiber B used in the composite yarn as the weft or warp yarn, it is possible to suppress the occurrence of wrinkles caused by the difference in thermal shrinkage between the warp and weft yarns, and to reduce the anisotropy in sliding durability caused by the difference in yarn strength.

[0026] The mass ratio α of fluororesin fiber A in the composite yarn is 5 to 70%. By setting the mass ratio α of fluororesin fiber A in the composite yarn to this value, it is possible to achieve an optimal balance between low friction, transfer of fluorine wear powder to fiber B, and the strength of fiber B as an aggregate. A more preferred range is 25 to 60%, and from the viewpoint of the balance between strength and sliding properties, a range of 40 to 55% is particularly preferred. If the mass ratio α of fluororesin fiber A in the composite yarn is less than 5%, low friction is significantly impaired. If it is more than 70%, breakage of the fluororesin fiber and discharge of fluorine wear powder become significant, making it impossible to obtain the desired durability.

[0027] The means for obtaining a composite yarn from fluororesin fiber A and fiber B is not particularly limited, and can be selected from means such as plying, blending, and blended spinning. When plying and blending are used, filament yarns can be selected as fluororesin fiber A and fiber B, which is preferable because it increases the strength of the composite yarn. When blending is used, the fluororesin fiber A single yarn and fiber B single yarn that make up the composite yarn can be more uniformly blended, resulting in a composite yarn that is uniform in the cross-sectional direction. When plying and twisting are used, a composite yarn can be obtained without entanglement, resulting in a composite yarn that is uniform in the longitudinal direction.

[0028] When a composite yarn is obtained by plying and twisting fluororesin fiber A and fiber B, the number of twists during plying and twisting is preferably such that the twist factor k is 1,000 or more and 25,000 or less. Here, the twist factor k is calculated by the following formula, where T [t / m] is the number of twists per meter and D [dtex] is the fineness of the composite yarn. k=T×D 0.5 More preferably, it is 1,000 or more and 10,000 or less, and particularly preferably 2,000 or more and 7,000 or less.

[0029] When a composite yarn is obtained by plying and twisting fluororesin fiber A and fiber B, it is preferable that fiber B be twisted before plying and twisting. Twisting can suppress the opening of fiber B due to abrasion during weaving, thereby preventing the phenomenon in which the opened fiber B covers the fluororesin fiber A in the composite yarn, impairing low friction. In this case, the twist coefficient of fiber B before plying and twisting is preferably 500 to 5,000. Furthermore, if it is 500 to 3,000, in addition to the above effects, the twisting improves the strength of fiber B, and when a woven fabric is made, fiber B exists more firmly as a skeletal fiber, improving sliding durability. A twist coefficient of 900 to 3,000 is particularly preferable. If the twist coefficient of fiber B is greater than 5,000, the strength may be lower than before twisting. When twisting fiber B, a process of simply twisting raw yarn of the desired fineness may be used, or a process of twisting yarns of a fineness smaller than the desired fineness may be used. For example, when preparing fiber B with a twist number of 33 [t / m] and a fineness of 850 [dtex], a raw yarn of fiber B with a fineness of 850 [dtex] may be twisted at 33 [t / m], or two raw yarns of fiber B with a fineness of 425 [dtex] may be ply-twisted at 33 [t / m].

[0030] In the woven fabric of the present invention, the ratio X / Y, where X is the area ratio of the fluororesin fiber A on the surface of the woven fabric and Y is the mass ratio of the fluororesin fiber A in the woven fabric, is 1 or more and 5 or less. The area ratio of the fluororesin fiber A on the surface of the woven fabric referred to here is the ratio of the photographed area S when the surface of the fabric is photographed with a microscope. tot The area S occupied by fluororesin fiber A A This means the ratio of

[0031] Area ratio of fluororesin fiber A X=S A / S tot ×100[%] X / Y represents the degree to which fluororesin fibers A present in the woven fabric are distributed on the surface of the woven fabric; a larger X / Y ratio means that the fluororesin fibers are concentrated on the surface of the woven fabric. To achieve excellent abrasion resistance, it is important to strike a balance between low friction at the initial stage of sliding and low friction as the woven fabric wears due to sliding. X / Y is preferably 1 to 2, and even more preferably 1.2 to 1.65. A ratio of 1.2 to 1.6 is particularly preferable, as it can achieve particularly excellent sliding durability while maintaining initial sliding properties. When X / Y is less than 1, the amount of fluororesin fibers A present on the surface of the woven fabric is reduced relative to the mass ratio of fluororesin fibers A in the woven fabric. Therefore, when subjected to high-speed sliding under a high load, the frictional resistance relative to the fabric strength is relatively high at the initial stage of sliding, which makes it prone to early breakage initiation and results in insufficient abrasion resistance. The larger the X / Y ratio, the greater the amount of fluororesin fiber A present on the surface of the fabric relative to the mass ratio of fluororesin fiber A in the fabric. When X / Y is greater than 5, the amount of fluororesin fiber A present on the surface of the fabric becomes excessively large. Therefore, when exposed to high-speed sliding under a high load, frictional resistance can be reduced in the early stages of sliding. However, the fluororesin fiber wear generates fluorine wear dust, which is quickly expelled and the fluororesin fiber remaining in the fabric is depleted. As a result, frictional resistance becomes relatively high compared to the fabric strength in the middle to late stages of sliding, and sufficient wear resistance cannot be achieved.

[0032] The area ratio X of the fluororesin fiber A on the surface of the woven fabric is preferably 10% or more and 60% or less. If the area ratio X of the fluororesin fiber A on the surface of the woven fabric is 10% or more, the frictional resistance force at the initial stage of sliding can be reduced to a certain extent and abrasion resistance can be ensured. If the area ratio X of the fluororesin fiber A on the surface of the woven fabric is 60% or less, fibers other than the fluororesin fiber can be present to a certain extent as skeletal fibers in the woven fabric, and abrasion resistance can be ensured. From the viewpoints of reducing the frictional resistance force at the initial stage of sliding and arranging skeletal fibers in the fabric, the area ratio X is more preferably 20% or more and 55% or less, and 40% or more and 55% or less is particularly preferred.

[0033] The mass ratio Y of the fluororesin fiber in the woven fabric is preferably 5% or more and 55% or less, more preferably 15% or more and 55% or less, and particularly preferably 25% or more and 45% or less.

[0034] For X / Y to satisfy the above range, it is preferable to arrange more of the fluororesin fiber on the surface of the woven fabric. That is, to make X / Y fall within the above range, when the composite yarn is made, more of the fluororesin fiber may be arranged near the surface layer of the composite yarn, or the weave may be controlled so that more of the fluororesin fiber is exposed on the surface of the woven fabric.

[0035] In the present invention, the means for obtaining a composite yarn is not particularly limited. However, in order to arrange a large amount of fluororesin fiber near the surface layer of the composite yarn, it is possible to relatively easily employ a plying / twisting process and control the plying / twisting conditions. Specifically, methods that can be employed include covering fiber B with fluororesin fiber A, plying a ply-twisted yarn of fiber B and fluororesin fiber A with fluororesin fiber A again, and applying high tension to fiber B during plying / twisting to arrange fluororesin fiber A on the sheath side of the composite yarn. When a composite yarn is obtained by plying / twisting fluororesin fiber A and fiber B without using the special methods described above, the volume ratio and area ratio of fluororesin fiber A in the composite yarn are approximately equal. Increasing the area ratio of fluororesin fiber in the composite yarn also increases the mass ratio Y of fluororesin fiber A in the woven fabric. Therefore, other means, such as controlling the weave, are usually used to control X / Y within the range of 1 to 5.

[0036] In the present invention, the weave is not particularly limited, but examples of means for controlling the weave to expose a large amount of fluororesin fiber on the surface of a fabric include adopting a 3 / 1 twill weave, a 2 / 1 twill weave, a satin weave, etc., and changing the exposed ratio of warp and weft on the surface. By arranging yarns containing a large amount of fluororesin fiber A in either the warp or weft that is more exposed on the surface, it is possible to control X / Y within the range of 1 or more and 5 or less. However, in a 2 / 2 twill weave or a simple plain weave, the warp and weft are exposed to the same extent on the surface, making it difficult to expose a large amount of fluororesin fiber on the surface of a fabric when a normal composite yarn is used.

[0037] In the present invention, the fluororesin that is a component of the fluororesin fiber may be any fluororesin composed of monomer units containing one or more fluorine atoms in the main chain or side chain, and among these, those composed of monomer units with a large number of fluorine atoms are preferred.

[0038] The monomer units containing one or more fluorine atoms preferably account for 70 mol % or more of the repeating structural units of the polymer, more preferably 90 mol % or more, and even more preferably 95 mol % or more.

[0039] Examples of the monomer containing one or more fluorine atoms include fluorine atom-containing vinyl monomers such as tetrafluoroethylene, hexafluoropropylene, and chlorotrifluoroethylene, and among these, it is preferable to use at least tetrafluoroethylene.

[0040] As the fluororesin, for example, polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-p-fluoroalkyl vinyl ether copolymer (PFA), polychlorotrifluoroethylene (PCTFE), ethylene-tetrafluoroethylene copolymer (ETFE), etc. can be used alone or in a blend of two or more types.

[0041] In fluororesins containing tetrafluoroethylene units, a higher content of tetrafluoroethylene units is preferable in terms of sliding properties, and copolymers in which 90 mol % or more, preferably 95 mol % or more of the total is tetrafluoroethylene are preferred, and it is most preferred to use polytetrafluoroethylene fibers as a tetrafluoroethylene homopolymer.

[0042] The fluororesin fiber A used in the present invention may be in the form of either a monofilament consisting of one filament or a multifilament consisting of multiple filaments, but is preferably a multifilament from the viewpoints of weaving properties and surface irregularities when made into a fabric.

[0043] The total fineness of the fluororesin fiber A used in the present invention is preferably within the range of 50 to 6000 dtex, more preferably within the range of 500 to 5500 dtex, and even more preferably within the range of 400 to 1500 dtex. If the total fineness of the fibers constituting the fabric is 50 dtex or more, the strength of the fibers can be ensured to a certain extent, and thread breakage during weaving can be reduced, improving processability. If it is 6000 dtex or less, good processability during weaving can be obtained.

[0044] Examples of fibers B that can be used include organic fibers such as cotton, polyester fibers, polyamide fibers, polyparaphenylene terephthalamide (para-aramid) fibers, polymetaphenylene isophthalamide (meta-aramid) fibers, polyphenylene sulfide (PPS) fibers, polyparaphenylene benzobisoxazole (PBO) fibers, ultra-high molecular weight polyethylene (UHMWPE) fibers, and liquid crystal polyester fibers, and inorganic fibers such as glass fibers, carbon fibers, and silicon carbide fibers, but from the viewpoint of processability, organic fibers are preferred.

[0045] From the viewpoint of improving the abrasion resistance of the woven fabric, it is preferable that Fiber B has a tensile strength of 7 cN / dtex or more. The tensile strength of Fiber B is more preferably 15 to 50 cN / dtex, and even more preferably 18 to 50 cN / dtex. This can further suppress fiber breakage even when high-speed sliding is applied under high load, and can help form a self-lubricating film due to wear of the fluororesin fiber.

[0046] From the viewpoint of durability in an environment where frictional heat is generated due to sliding, it is preferable that fiber B has a heat resistance temperature of 280°C or higher. Here, "heat resistance temperature" means that the melting point, softening point, or decomposition point is equal to or higher than that temperature. If fiber B has two or more of the melting point, softening point, and decomposition point, the lower temperature is used. It is more preferable that the heat resistance temperature of the fiber be 300°C or higher. Furthermore, by using a fiber that does not have a melting point, softening due to frictional heat can be suppressed, resulting in excellent wear resistance.

[0047] From the viewpoint of dimensional stability of the woven fabric, it is preferable that fiber B has a tensile modulus of 20 to 800 cN / dtex. Furthermore, if fiber B has a tensile modulus in the range of 450 to 800 cN / dtex, the fabric structure can be maintained even when subjected to high-speed sliding under high load, resulting in particularly excellent abrasion resistance. If fiber B has a tensile modulus of 20 cN / dtex or more, the dimensional stability of the fabric is improved, resulting in a fabric with excellent abrasion resistance. If the tensile modulus is 800 cN / dtex or less, the rigidity of the fiber is not too high, and weaving properties are not impaired even when interwoven with low-rigidity fluororesin fibers, which is preferable. The elongation of fiber B is preferably 1 to 15%, more preferably 1 to 5%. Among these, a value of 1 to 3% is particularly preferable because it can reduce dimensional change of the fabric when frictional force is applied. If fiber B has an elongation of 1% or more, thread breakage during weaving is reduced, improving processability. If the thickness is within the range of 1 to 15%, the dimensional stability of the fabric is improved, and the fabric can be used in areas where dimensional accuracy is required as a sliding fabric.

[0048] In view of the above, it is particularly preferable that fiber B is a fiber selected from liquid crystal polyester fiber, para-aramid fiber, and polyparaphenylene benzobisoxazole fiber.

[0049] The form of fiber B is not particularly limited, and either filament (long fiber) or spun (spun yarn) may be used, but filament is preferred from the viewpoint of tensile strength and tensile rigidity. Furthermore, either a monofilament consisting of one filament or a multifilament consisting of multiple filaments can be used, but multifilament is particularly preferred because it has a large surface area and fluorine abrasion powder generated by abrasion of fluororesin fiber A can easily be transferred to fiber B.

[0050] The total fineness of fiber B is preferably within the range of 200 to 4000 dtex, more preferably within the range of 4000 to 4000 dtex, and even more preferably within the range of 800 to 2000 dtex. When the total fineness of the fibers constituting the fabric is 200 dtex or more, the strength of the fibers is high, fiber breakage during abrasion can be suppressed, and thread breakage during weaving can be reduced, improving processability. When the total fineness is 4000 dtex or less, unevenness on the fabric surface can be reduced, minimizing the impact on low friction properties.

[0051] To further enhance the abrasion resistance of the woven fabric obtained by the above-described method, the woven fabric can be impregnated with a resin. Here, the resin to be impregnated can be a thermosetting resin or a thermoplastic resin. Thermosetting resins include, but are not limited to, phenolic resin, melamine resin, urea resin, unsaturated polyester resin, epoxy resin, polyurethane resin, diallyl phthalate resin, silicone resin, polyimide resin, vinyl ester resin, and modified resins thereof. Thermoplastic resins include vinyl chloride resin, polystyrene resin, ABS resin, polyethylene resin, polypropylene resin, fluororesin, polyamide resin, polyacetal resin, polycarbonate resin, and polyester resin. Furthermore, synthetic rubbers or elastomers such as thermoplastic polyurethane, butadiene rubber, nitrile rubber, neoprene, and polyester elastomers are preferred. Among these, resins primarily composed of phenolic resin and polyvinyl butyral resin, polyolefin resins such as unsaturated polyester resin, vinyl ester resin, polyethylene, and polypropylene, and polyester resins are preferred due to their impact resistance, dimensional stability, strength, and cost. These thermosetting and thermoplastic resins may contain various additives that are commonly used industrially for their purpose, application, productivity in the manufacturing and processing steps, or to improve properties. For example, modifiers, plasticizers, fillers, release agents, colorants, diluents, etc. may be added. Note that the term "major component" as used herein refers to the component with the largest mass ratio among the components excluding the solvent. In the case of a resin whose main components are a phenolic resin and a polyvinyl butyral resin, this means that the mass ratios of these two resins are first and second (in no particular order).

[0052] As a method for impregnating the woven fabric with a resin, when a thermosetting resin is used, a method is generally used in which the thermosetting resin is dissolved in a solvent to prepare a varnish, and the varnish is impregnated and coated onto the fabric by knife coating, roll coating, comma coating, gravure coating, etc. When a thermoplastic resin is used, melt extrusion lamination, etc. is generally used.

[0053] If necessary, a lubricant or the like can be added to the woven fabric of the present invention. The type of lubricant is not particularly limited, but a silicon-based lubricant or a fluorine-based lubricant is preferred.

[0054] The woven fabric of the present invention thus obtained is a ply-twisted woven fabric with an optimized composition of fluororesin fiber A and non-fluororesin fiber B. Therefore, even when subjected to high-speed sliding under high load, it suppresses the emission of fluorine wear particles. Furthermore, fiber B functions as a skeletal fiber supporting fluororesin fiber A, resulting in long-term sliding durability. Therefore, the woven fabric of the present invention can exhibit high sliding durability in applications that have traditionally been difficult to use for long periods due to high-speed sliding under high load, achieving extremely high industrial practicality. Therefore, it exhibits high durability in applications requiring sliding properties, such as sliding fabrics. It is particularly preferred for use in cable covers for robot arms. A cable cover for a robot arm using at least a portion of the woven fabric of the present invention has low friction and fabric strength, resulting in a long product life even in usage environments where it rubs against parts of equipment at high speed under high load. [Example]

[0055] Examples of the present invention will be described below together with comparative examples.

[0056] The methods for measuring various properties used in the present examples are as follows.

[0057] (1) Fineness The fabric was disassembled and the fineness of the disassembled yarn was measured in accordance with 8.3.B (simplified method) of JIS L1013:2010 "Testing methods for chemical fiber filament yarn." However, if the amount of disassembled yarn required for the above measurement method cannot be secured, the results of testing with the maximum length and number of trials that can be secured shall be used instead.

[0058] (2) Tensile strength of the fiber The fabric was disassembled and the breaking strength of the disassembled yarn was measured in accordance with 8.5 of JIS L1013:2010 "Testing Methods for Chemical Fiber Filament Yarns." However, if the amount of disassembled yarn required for the above measurement method cannot be secured, the results of the test using the maximum length and number of trials that can be secured shall be used instead.

[0059] (3) Fiber elongation The fabric was disassembled, and the elongation (elongation rate) of the disassembled yarn was measured in accordance with 8.5 of JIS L1013:2010 "Testing methods for chemical fiber filament yarn." However, if the amount of disassembled yarn required for the above measurement method cannot be secured, the results of the test using the maximum length and number of trials that can be secured shall be used instead.

[0060] (4) Tensile modulus In the measurement of (3), the elastic modulus was calculated from the modulus at an elongation of 0.5% (the average slope from an elongation of 0.45% to an elongation of 0.55%).

[0061] (5) Mass ratio α of fluororesin fiber A in the composite yarn After cutting the fabric into a 200mm x 200mm length, the warp and weft yarns were separated to obtain separated yarns. Five composite yarns were randomly selected from the obtained separated yarns for each of the warp separated yarns and weft separated yarns, and they were separated into fluororesin fiber A and other fibers, and the mass of each was measured. The total mass of the five composite yarns was W, and the total mass of the fluororesin fiber A in the five composite yarns was W. F The mass ratio α of the fluororesin fiber A in the composite yarn was calculated using the following formula. α=W F / W×100[%] However, if the amount of yarn required for the above measurement method cannot be secured for the disassembled yarn, the results of the test using the maximum length and number of trials that can be secured shall be used instead.

[0062] (6) Weave density In accordance with 8.6.1 of JIS L1096:2010 "Testing methods for woven and knitted fabrics," the sample was placed on a flat table, and unnatural wrinkles and tension were removed. The number of warp and weft threads within 50 mm intervals at different points was counted, and the average value for each was calculated for each unit length.

[0063] (7) Area ratio X of fluororesin fiber A on the fabric surface The fabric was photographed at 50x magnification using a Keyence microscope, VHX-2000, and the photographed area was measured as S tot , and the area occupied by fluororesin fiber A is S A The area ratio of fluororesin fiber A was calculated using the following formula: However, if X differs between the front and back surfaces, the larger X value is used as the representative value. Area ratio of fluororesin fiber A X=S A / S tot ×100[%] In addition, the shooting area S tot and the area S occupied by fluororesin fiber A A was calculated using the image analysis software "WinR00F2015" manufactured by Mitani Corporation.

[0064] (8) Mass ratio Y of fluororesin fiber A in the fabric After cutting the woven fabric into a 200mm x 200mm length, the warp and weft yarns were separated and the total mass W of the separated yarns was measured. Next, only the composite yarns were selected from the separated yarns, and the total mass W1 of the composite yarns in the woven fabric was measured. Next, the fluororesin fiber that was present alone in the woven fabric, rather than the composite yarns, was selected and its total mass W2 was measured. The mass ratio Y of fluororesin fiber A in the woven fabric was calculated using the following formula. Y = (W1 × α / 100 + W2) / W × 100 [%] However, if the amount of yarn required for the above measurement method cannot be secured for the disassembled yarn, the results of the test using the maximum length and number of trials that can be secured shall be used instead.

[0065] (9) Number of twists The fabric was disassembled, and the twist number of the disassembled yarn was measured in accordance with 8.13.1 of JIS L1013:2010 "Testing method for chemical fiber filament yarn." However, if the amount of yarn required for the above measurement method cannot be secured for the disassembled yarn, the results of testing using the maximum length and number of trials that can be secured may be used instead.

[0066] (10) Coefficient of dynamic friction Measurement was carried out by the ring wear test shown below.

[0067] According to Method A of JIS K7218:1986 "Sliding abrasion test method for plastics," the fabric was sampled to a length of 30 mm and a width of 30 mm, placed on a SUS plate of the same size and approximately 3 mm thick, and fixed in a sample holder.

[0068] The mating material was a hollow cylindrical ring made of S45C with an outer diameter of 25.6 mm, an inner diameter of 20 mm, and a length of 15 mm. The surface of the ring was polished with a sandpaper to adjust the surface roughness to Ra = 0.8 μm ± 0.1. A roughness measuring instrument (Mitutoyo "SJ-201") was used to measure the roughness.

[0069] The ring wear tester used was an A&D Model EFM-III-EN, and tests were conducted under a friction load of 20 MPa and a friction speed of 400 mm / s. The sliding torque was measured and the average friction coefficient up to break was calculated. Since the static friction coefficient is included immediately after the start of sliding, the average friction coefficient from 1 second after the start of sliding (sliding distance 0.4 m) to break was calculated as the dynamic friction coefficient.

[0070] The coefficient of dynamic friction was rated as A if it was less than 0.055, B if it was 0.055 or more and 0.060 or less, C if it was more than 0.060 and 0.065 or less, and D if it was greater than 0.065.

[0071] (11) Sliding durability distance In the ring abrasion test, sliding was continued until the fabric broke. Those that did not break after 60 m of sliding were rated A, those that broke after 50 m or more but less than 60 m were rated B, those that broke after 40 m or more but less than 50 m were rated C, those that broke after 25 m or more but less than 40 m were rated D, and those that broke after a sliding distance of less than 25 m were rated E.

[0072] Example 1 A composite yarn was obtained by plying and twisting a PTFE fiber ("Toyoflon" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 880 dtex, 120 filaments per single yarn, and 33 t / m twist with a liquid crystal polyester fiber ("Scivelas" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 850 dtex, 144 filaments per single yarn, and 33 t / m twist at a twist of 167 t / m. A 3 / 1 twill fabric was then produced on a loom using the ply and twisted yarn as the warp and a liquid crystal polyester fiber ("Scivelas" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 1700 dtex and 288 filaments per single yarn as the weft. The fabric was then scoured in a scouring tank at 80°C and heat-set at 180°C.

[0073] Example 2 A woven fabric was obtained in the same manner as in Example 1, except that the composite yarn used in Example 1 was used as the warp and weft.

[0074] Comparative Example 1 A woven fabric was obtained in the same manner as in Example 1, except that PTFE fiber ("Toyoflon" (registered trademark), manufactured by Toray Industries, Inc.) with a total fineness of 1760 dtex and a single filament count of 240 was used for the weft.

[0075] Example 3 A liquid crystal polyester fiber ("Scivellus"®, Toray Industries, Inc.) with a total fineness of 425 dtex and a single filament count of 72 filaments was plied and twisted with a PTFE fiber ("Toyoflon"®, Toray Industries, Inc.) with a total fineness of 880 dtex and a single filament count of 120 filaments. The plied and twisted yarn was then plied and twisted with a liquid crystal polyester fiber with a total fineness of 425 dtex and a single filament count of 72 filaments at a twist rate of 167 t / m to obtain a plied and twisted yarn. A 3 / 1 twill fabric was produced on a loom using the plied and twisted yarn as the warp and liquid crystal polyester fiber ("Scivellus"®, Toray Industries, Inc.) with a total fineness of 1700 dtex and a single filament count of 288 filaments as the weft. The fabric was then scoured in a scouring tank at 80°C and heat-set at 180°C.

[0076] Example 4 A liquid crystal polyester fiber ("Scivellus"®, manufactured by Toray Industries, Inc.) with a total fineness of 850 dtex and a single filament count of 144 filaments was plied and twisted with a PTFE fiber ("Toyoflon"®, manufactured by Toray Industries, Inc.) with a total fineness of 440 dtex and a single filament count of 60 filaments. The plied and twisted yarn was then plied and twisted with a PTFE fiber ("Toyoflon"®, manufactured by Toray Industries, Inc.) with a total fineness of 440 dtex and a single filament count of 60 filaments at a twist rate of 167 t / m to obtain a plied and twisted yarn. A 3 / 1 twill fabric was produced on a loom using the plied and twisted yarn as the warp and liquid crystal polyester fiber ("Scivellus"®, manufactured by Toray Industries, Inc.) with a total fineness of 1700 dtex and a single filament count of 288 filaments as the weft. The fabric was then scoured in a scouring tank at 80°C and heat-set at 180°C.

[0077] Example 5 A woven fabric was obtained in the same manner as in Example 1, except that the twist number of fiber B before plying was set to 0 t / m.

[0078] Example 6 A PTFE fiber ("Toyoflon" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 440 dtex, a single yarn count of 60 filaments, and a twist count of 33 t / m was plied with a liquid crystal polyester fiber ("Scivelas" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 1275 dtex, a single yarn count of 216 filaments, and a twist count of 33 t / m at a twist count of 167 t / m to obtain a plied and twisted yarn. A 3 / 1 twill fabric was then produced on a loom using the plied and twisted yarn as the warp and liquid crystal polyester fiber ("Scivelas" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 1700 dtex and a single yarn count of 288 filaments as the weft. The fabric was then scoured in a scouring tank at 80°C and heat-set at 180°C.

[0079] Example 7 A woven fabric was obtained in the same manner as in Example 6, except that the composite yarn used in Example 6 was used as the warp and weft.

[0080] Comparative Example 2 A woven fabric was obtained in the same manner as in Example 6, except that the warp yarn used in Example 6 was used as the weft yarn, and the weft yarn used in Example 6 was used as the warp yarn.

[0081] Example 8 A PTFE fiber ("Toyoflon"®, manufactured by Toray Industries, Inc.) with a total fineness of 880 dtex, 120 filaments per filament, and 33 t / m twist was plied with a polyparaphenylene terephthalamide fiber ("Kevlar"®, manufactured by DuPont-Toray Co., Ltd.) with a total fineness of 850 dtex, 144 filaments per filament, and 33 t / m twist, at a twist of 167 t / m to obtain a plied and twisted yarn. A 3 / 1 twill fabric was then woven on a loom using the plied and twisted yarn as the warp and polyparaphenylene terephthalamide fiber ("Kevlar"®, manufactured by DuPont-Toray Co., Ltd.) with a total fineness of 1700 dtex and 288 filaments per filament as the weft. The fabric was then scoured in a scouring tank at 80°C and heat-set at 180°C.

[0082] Example 9 A PTFE fiber ("TOYOFLON" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 880 dtex, 120 filaments per single yarn, and 33 t / m twist was plied with a polyester fiber ("TETORON" polyethylene terephthalate fiber manufactured by Toray Industries, Inc.) with a total fineness of 850 dtex, 144 filaments per single yarn, and 33 t / m twist at a twist of 167 t / m to obtain a plied and twisted yarn. A 3 / 1 twill fabric was then produced on a loom using the plied and twisted yarn as the warp and polyester fiber ("TETORON" polyethylene terephthalate fiber manufactured by Toray Industries, Inc.) with a total fineness of 1700 dtex and 288 filaments per single yarn as the weft. The fabric was then scoured in a scouring tank at 80°C and heat-set at 180°C.

[0083] Example 10 A PTFE fiber ("TOYOFLON" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 880 dtex, a single filament count of 120 filaments, and a twist count of 33 t / m was plied with a polyphenylene sulfide fiber ("TORCON" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 850 dtex, a single filament count of 144 filaments, and a twist count of 33 t / m at a twist count of 167 t / m to obtain a plied and twisted yarn. A 3 / 1 twill fabric was then produced on a loom using the plied and twisted yarn as the warp and polyphenylene sulfide fiber ("TORCON" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 1700 dtex and a single filament count of 288 filaments as the weft. The fabric was then scoured in a scouring tank at 80°C and heat-set at 180°C.

[0084] Comparative Example 3 A PTFE fiber ("Toyoflon" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 440 dtex, single yarn count of 60 filaments, and twist count of 33 t / m was plied with a polyester fiber ("Tetoron" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 44 dtex and single yarn count of 18 filaments at a twist count of 210 t / m to obtain a plied yarn. Then, a five-ply satin fabric was produced on a loom using the plied yarn as the warp and polyester fiber ("Tetoron" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 26 s / 2 (454 dtex) as the weft. The fabric was then scoured in a scouring tank at 80°C and heat-set at 180°C.

[0085] Comparative Example 4 A PTFE fiber ("Toyoflon" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 2660 dtex, 360 filaments per single yarn, and 33 t / m twist was ply-twisted with a carbon fiber ("Torayca" (registered trademark) manufactured by Toray Industries, Inc.) with a total fineness of 1980 dtex, 3000 filaments per single yarn, and 33 t / m twist, at a twist of 167 t / m to obtain a ply-twisted yarn. A 2 / 2 twill fabric was then produced on a loom using this ply-twisted yarn as the warp and weft. The fabric was then scoured in a scouring tank at 80°C and heat-set at 180°C.

[0086] Tables 1 and 2 show the evaluation results of the composite yarn configuration, fabric configuration, dynamic friction coefficient, and sliding durability distance for the woven fabrics described in the Examples and Comparative Examples.

[0087] [Table 1]

[0088] [Table 2]

Claims

1. A woven fabric using a composite yarn of a fluororesin fiber A and a fiber B other than the fluororesin fiber as at least one of the warp and weft, wherein the mass ratio α of the fluororesin fiber A in the composite yarn is 5 to 60%, and the ratio X / Y, where X is an area ratio of the fluororesin fiber on the surface of the woven fabric and Y is a mass ratio of the fluororesin fiber in the woven fabric, is 1 or more and 1.65 or less.

2. 2. The woven fabric according to claim 1, wherein a composite yarn is used as either the warp or weft yarn, and fiber B is used as either the weft or warp yarn perpendicular to the composite yarn.

3. The woven fabric according to claim 1 or 2, wherein the area ratio X is 10% or more and 60% or less.

4. The woven fabric according to any one of claims 1 to 3, wherein the composite yarn is a plied yarn obtained by plied-twisting a fluororesin fiber A and a fiber B other than a fluororesin fiber.

5. The woven fabric according to claim 4, wherein the fiber B constituting the ply-twisted yarn is a twisted yarn.

6. The woven fabric according to any one of claims 1 to 5, wherein the fluororesin fiber A is made of polytetrafluoroethylene resin.

7. The woven fabric according to any one of claims 1 to 6, wherein the fiber B is a fiber having a tensile strength of 7 cN / dtex or more.

8. The woven fabric according to claim 7, wherein the fiber B has a tensile strength of 15 to 50 cN / dtex.

9. The woven fabric according to any one of claims 1 to 8, wherein the fiber B is a fiber having a heat resistance temperature of 280°C or higher.

10. The woven fabric according to any one of claims 1 to 9, wherein the fiber B has a tensile modulus of 450 to 800 cN / dtex.

11. The woven fabric according to any one of claims 1 to 10, wherein the fiber B is an organic fiber.

12. The woven fabric according to any one of claims 1 to 11, wherein the fiber B is a fiber selected from the group consisting of a liquid crystal polyester fiber, a para-aramid fiber, and a polyparaphenylene benzobisoxazole fiber.

13. A cable cover for a robot arm, at least part of which uses the woven fabric according to any one of claims 1 to 12.

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