JP2010285706A - Electroconductive woven or knitted fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a woven or knitted fabric in which an electroconductive fiber is prevented from being protruded from the surface of the woven or knitted fabric, by which sufficient electroconductive properties are exhibited even when a sewn part is sandwiched, and of which the electroconductive properties can be maintained even after high-temperature washing. <P>SOLUTION: The electroconductive woven or knitted fabric is the woven or knitted fabric comprising a mixed yarn comprising an electroconductive fiber and a fiber except the fiber, and a yarn except the mixed yarn, and is regulated so that the ratio (A/B) of the total fineness A of the mixed yarn to the total fineness B of the yarn except the mixed yarn may be from 1.1 to 5.0, and surface leakage resistances while sandwiching the sewn part before and after wet heat treatment at 121°C for 25 h may be each 1×10<SP>9</SP>Ω or less. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a woven or knitted fabric excellent in electrical conductivity. More specifically, the present invention relates to a woven or knitted fabric that can be preferably used for uniform garments worn when manufacturing electronic devices, electronic components, electronic materials, chemicals, and the like.

  Fibers made of hydrophobic polymers such as polyester, polyamide, and polyolefin have many advantages such as mechanical properties, chemical resistance, and weather resistance, and are widely used not only for clothing but also for industrial materials. However, these fibers generate a large amount of static electricity due to friction, etc., and attract the dust in the air to impair the aesthetics, cause problems with electronic devices due to sparks, and flammable explosions to flammable substances. In some cases, many studies have been made to provide conductive performance to solve this problem.

  Patent Document 1 describes a core-sheath type composite fiber in which a conductive component containing conductive particles such as conductive carbon black and metal powder is wrapped with a non-conductive component. In such a core-sheath type composite fiber, the conductive particles are present only inside the fiber, so that trouble during operation is unlikely to occur and production with good operability is possible. However, since the conductive particles exist only inside the fiber, it is difficult to give sufficient conductive performance to the woven or knitted fabric.

  Patent Document 2 describes a core-sheath type conductive fiber in which a conductive component containing conductive particles is arranged in a sheath part. If such a conductive fiber is used, sufficient conductive performance can be imparted to the woven or knitted fabric, but on the other hand, smooth operation may be hindered.

  Usually, the conductive fiber contains conductive carbon black or the like, and therefore tends to have poor stretchability. Moreover, the woven or knitted fabric having conductive performance is not composed of only conductive fibers, and other fibers are often used in combination. For this reason, when such a woven or knitted fabric is applied to a uniform garment, although it depends on the degree of expansion and contraction of the entire woven or knitted fabric, a part of the conductive fiber having poor elasticity jumps out to the surface of the woven or knitted fabric and becomes conductive due to friction or wear There is a problem that the fiber is cut. At the same time, the conductive fibers are poor in stretchability, so that the elongation of the entire woven or knitted fabric is hindered, and as a result, the strong elongation characteristics of the woven or knitted fabric are easily impaired.

  Patent Document 3 discloses a double covering elastic yarn in which an elastic fiber is used as a core yarn and a synthetic fiber filament yarn is wound twice around the elastic yarn. In this yarn, a conductive yarn containing conductive inorganic powder is used as the lower winding yarn for covering, and a crimped yarn is used as the upper winding yarn for covering.

  However, the covering elastic yarn is intended to remove static electricity and is used for stockings and the like. For this reason, the conductive performance is insufficient to be applied to uniform clothing. Another problem remains in that it cannot be sufficiently prevented from jumping out onto the surface of the woven or knitted fabric.

  Therefore, in Patent Document 4, a synthetic composite long fiber yarn is used as a core yarn and a conductive composite spun yarn is double-covered around the synthetic yarn. A woven or knitted fabric is disclosed in which the yarn is arranged on the other side of the warp and weft.

  However, in this knitted or knitted fabric, depending on the difference in fineness between the conductive composite spun yarn and the other constituent fibers, or the constituent ratio of the conductive composite spun yarn, when the surface leakage resistance value was measured with the sewing part sandwiched, it was stable. There is a problem that it is difficult to obtain a resistance value. In particular, when applied to uniform clothing, there remains a problem that the difference in the surface leakage resistance value between the state where the sewing part is sandwiched and the state where the sewing part is not sandwiched becomes large.

JP 09-143821 A WO2002 / 075030 JP-A-11-279881 Japanese Patent No. 3880743

  All of the knitted and knitted fabrics described in each of the above patent documents are applied to uniform garments worn when manufacturing electronic parts, chemicals, and the like. These uniform garments are required to have heat and moisture resistance sufficient to withstand washing at high temperatures, unlike ordinary uniform garments. However, in each patent document, although improvement of conductive performance has been studied, none of them is intended for high-temperature washing, and in this case, appropriate conductive performance is considered in consideration of the use of the woven or knitted fabric. It is hard to say that you are doing.

  The present invention solves the above-mentioned problems, can suppress the jumping out of conductive fibers on the surface of the woven or knitted fabric, and can exhibit sufficient conductive performance even when the sewing part is sandwiched between them. It is a technical problem to provide a woven or knitted fabric that can be maintained later.

The inventors of the present invention have arrived at the present invention as a result of studies to solve the above problems. That is, the present invention is a woven or knitted fabric composed of a blended yarn composed of conductive fibers and other fibers and a yarn other than the blended yarn, and the total fineness A of the blended yarn and the blended yarn. The ratio (A / B) to the total fineness B of the yarns other than the yarn is 1.1 to 5.0, and the surface leakage resistance value in the state where the sewing part is sandwiched is wet at 121 ° C. for 25 hours. The gist is a woven or knitted fabric characterized by being 1 × 10 ⁹ Ω or less before and after the heat treatment.

  According to the present invention, it is possible to provide a woven or knitted fabric that can prevent the conductive fibers from jumping out on the surface of the woven or knitted fabric, can exhibit sufficient conductive performance even when the sewing portion is sandwiched, and can maintain the conductive performance even after high-temperature washing. Can do.

  However, the woven or knitted fabric of the present invention is suitable for uniform garments worn when manufacturing electronic devices, electronic components, electronic materials, chemicals, and the like.

  Hereinafter, the present invention will be described in detail.

  In the woven or knitted fabric of the present invention, a mixed yarn composed of conductive fibers and other fibers is used. As the conductive fiber, a fiber composed of only a single component of a conductive component can be used, but a composite fiber composed of a non-conductive component and a conductive component is preferably used. In this case, the former is generally composed of a fiber-forming polymer, and examples of the fiber-forming polymer include synthetic resins such as polyester resins and nylon resins, and polyester resins are particularly preferable. On the other hand, the fiber-forming polymer is also used for the latter, but the conductive performance cannot be exhibited only by this, so that it is used, for example, by containing conductive particles described later.

  The shape of the conductive fiber is generally preferably a filament (long fiber), and in actual use, it is preferably used in the form of a so-called filament yarn in which a plurality of filaments are bundled.

  When the conductive fiber is a composite fiber, any combination of the above two components can be adopted as long as the conductive performance can be kept good, but preferably in the longitudinal direction of the fiber. On the other hand, a mode is adopted in which a part of the conductive component is exposed on the fiber surface in a cross section cut perpendicularly. In particular, an embodiment in which the conductive component communicates near the center of the fiber and a plurality of conductive components are exposed on the fiber surface is preferable. As a result, there are conductive contacts on the surface of the fiber, and the electrical flow between the contacts through the central part enables multi-directional flow. it can. However, when the number of exposed portions of the conductive component increases, the exposed area of the conductive component on the fiber surface increases, and as a result, cracks and omissions tend to occur after the wet heat treatment.

  The number of conductive components exposed on the fiber surface is preferably about 2 to 20 locations, and more preferably 3 to 8 locations. When the portion exposed on the fiber surface of the conductive component is one place, the portion exposed on the fiber surface is subjected to a wet heat treatment, and when cracks occur or are damaged or missing, There is a tendency that the conductive performance becomes insufficient and the original conductive performance cannot be maintained. On the other hand, when there are more than 20 exposed portions of the conductive component on the fiber surface, the exposed portion on the fiber surface tends to increase, and cracks and missing after the wet heat treatment tend to occur.

  And as a ratio of the exposed area of the electroconductive component in the fiber surface, it is preferable to set it as 3/4 or less of a circumference, and 1/2 or less especially, More preferably, it is 1/3 to 1/10.

  The composite ratio of the non-conductive component and the conductive component is preferably 60 to 90% by mass of the non-conductive component and 40 to 10% by mass of the conductive component, more preferably in the fiber. The non-conductive component is 70 to 85% by mass, and the conductive component is 30 to 15% by mass. If the composite ratio of the conductive component is less than 10% by mass, the conductive performance may not be sufficiently exhibited. On the other hand, if the composite ratio of the conductive component exceeds 40% by mass, the yarn quality performance such as the strength elongation property may be deteriorated. Neither is inferior, or troubles during operation and cracks after wet heat treatment are likely to occur.

  Moreover, in this invention, the electroconductive performance of an electroconductive fiber is evaluated by an electrical resistance value. The electrical resistance value is measured as follows according to the AATCC76 method. That is, the conductive fiber (the number of filaments is not limited) is cut to about 15 cm in the length direction, and 10 samples are collected. Apply keratin cream to the surface of both ends of this sample, connect this surface part to a metal terminal, apply a 50V direct current with a sample measurement length of 10 cm, and measure the current value. Is calculated. The arithmetic average value of the calculated electric resistance values of 10 samples is used.

Electric resistance value = E / (I × L)
However, E: Voltage (V) I: Measurement current (A) L: Measurement length (cm)

The conductive fiber according to the present invention preferably has an electrical resistance value of 1 × 10 ⁴ to 1 × 10 ⁷ Ω / cm, preferably 1 × 10 ⁴ to 1 × 10 ⁶ Ω / cm, as the conductive performance. Is more preferable. When the electric resistance value exceeds 1 × 10 ⁷ Ω / cm, the conductive performance becomes insufficient depending on the application used, which is not preferable. On the other hand, if it is attempted to make the electric resistance value less than 1 × 10 ⁴ Ω / cm, a large amount of conductive particles are contained in the polymer. As a result, not only the physical properties of fibers are adversely affected, but also spinning and drawing are hindered. This is not preferable.

  The woven or knitted fabric of the present invention is suitable for surgical gowns and lab coats used in pharmaceutical factories, IT-related offices, hospitals, etc., uniforms for food factories, and the like. These garments are usually periodically (repeatedly) subjected to wet heat treatment using high-pressure steam for sterilization purposes. Therefore, it can be said that it is preferable to provide the conductive fiber itself with appropriate heat and moisture resistance. As described later, it is possible to provide the conductive fiber itself with desired moisture and heat resistance, for example, an antimony compound and a phosphorus compound in the fiber. It is possible by adding a specific amount of. In this respect, it has already been described that the polyester-based resin can be preferably applied to the fiber-forming polymer of the conductive fiber. However, when such a compound is contained in the fiber, the carboxyl end group concentration of the polyester polymer can be reduced, Thereby, good wet heat resistance can be maintained even if wet heat treatment is repeated.

  The index of the heat and moisture resistance of the conductive fiber itself is determined based on general wet heat treatment conditions for the uniform clothing. The wet heat treatment conditions in this case are usually about 5 to 15 minutes at a temperature of 121 to 135 ° C., but in the present invention, a temperature of 121 ° C., which is the most common wet heat treatment condition, and a treatment time of 15 minutes are adopted. Assuming that this process is repeated 100 times, an index to be adopted is determined. That is, in the present invention, the wet heat resistance is evaluated by comparing before and after the wet heat treatment at 121 ° C. for 25 hours. As specific evaluation items of the heat and moisture resistance, the conductive performance deterioration rate and the strength retention rate are adopted from the viewpoint of including main physical properties in the evaluation items.

  Here, the rate of decrease in conductive performance after the wet heat treatment (treatment at 121 ° C. for 25 hours) of the conductive fiber is calculated as follows.

Conductive performance reduction rate = (Y / X)
X: Electrical resistance value (Ω / cm) of the conductive fiber before wet heat treatment
Y: Electrical resistance value after wet heat treatment of conductive fiber (Ω / cm)

  The rate of decrease in the conductive performance of the conductive fiber is preferably 20 or less, and more preferably 10 or less. Normally, when the rate of decrease in conductivity performance exceeds 100, the fiber becomes a fiber whose electric resistance value is greatly reduced by wet heat treatment such as sterilization treatment. Even if it has conductivity performance before treatment, it has conductivity performance after treatment. In other words, the durability is inferior and the conductive performance cannot be sufficiently exhibited in each application. In this respect, by setting it to 20 or less, the woven or knitted fabric is less deteriorated in conductive performance and excellent in durability.

  On the other hand, the strength retention of the conductive fiber is calculated based on the tensile strength of the fiber. That is, the strength of the untreated fiber is measured at a gripping interval of 20 cm using a constant-speed extension type tester according to the standard time test of tensile strength and elongation described in JIS L1013. Next, after performing wet heat treatment at 121 ° C. for 25 hours, the strength of the fiber is obtained again by the same method. And it calculates based on the following formula | equation.

Strength retention (%) = (S / M) × 100
S: Tensile strength after wet heat treatment of conductive fibers (cN / dtex)
M: Tensile strength (cN / dtex) of the conductive fiber before wet heat treatment

  The strength retention of the conductive fibers is preferably 70% or more, and more preferably 75% or more. In the fiber obtained by a conventional method, the strength retention is 50% or less. In this case, as the sterilization process is repeated, the decrease in strength increases, and damage is caused by a load caused by wearing, so that the fibers are cut or the quality deteriorates, and at the same time, the conductive performance also decreases. In this respect, if the strength retention is 70% or more, it is advantageous in that a decrease in strength is suppressed in the woven or knitted fabric after the wet heat treatment.

  The conductive fiber used in the present invention preferably has predetermined moisture and heat resistance as described above. However, as one means for realizing this, an antimony compound and a phosphorus compound are represented by the following formula ( A means for containing 1) to (2) in a satisfactory amount at the same time is mentioned.

(1) 0.5 × 10 ⁻⁴ ≦ [Sb] ≦ 3.0 × 10 ⁻⁴
(2) 0.1 × 10 ⁻⁴ ≦ [P] ≦ 20.0 × 10 ⁻⁴
[Sb] represents the content of the antimony compound, [P] represents the content of the phosphorus compound, and the unit is "mol / acid component mole".

  Examples of the antimony compound include antimony trioxide, antimony chloride, and antimony acetate. Among them, antimony trioxide is preferably used from the viewpoint of polycondensation catalytic activity, physical properties of the resulting polyester fiber and cost.

  A characteristic of the antimony compound is that it exhibits sufficient polycondensation activity, but has an action of promoting thermal decomposition in the latter stage of the polycondensation reaction. However, when it is added in a large amount, the amount of carboxyl end groups in the polyester is increased, and the fiber tends to have a reduced wet heat resistance.

  The addition amount of the antimony compound is preferably reduced within a range in which a sufficient polycondensation reaction rate is exhibited, and the content of the antimony compound in the conductive fiber preferably satisfies the formula (1).

The content of the antimony compound in the fiber is preferably 0.8 × 10 ⁻⁴ ≦ [Sb] ≦ 2.5 × 10 ⁻⁴ among the range defined by the formula (1). When the value is less than the value determined by the formula (1), sufficient polycondensation activity is not exhibited, and the polycondensation reaction time becomes longer, so that the thermal decomposition reaction proceeds, the carboxyl end group concentration increases, and as a result, the heat and humidity resistance becomes poor It tends to be unfavorable. On the other hand, when the content of the antimony compound in the fiber is larger than the value determined by the formula (1), not only the color tone of the fiber is deteriorated, but also the thermal decomposition reaction is promoted, so that the carboxyl end group concentration is high. Similarly, the heat and heat resistance tends to be poor, which is not preferable.

In addition, the conductive fiber in the present invention preferably contains a phosphorus compound in addition to the antimony compound. The content of the phosphorus compound in the fibers, more be (2) is preferably limited to an amount which satisfies the equation, among others 0.5 × ^{10 -4} ≦ [P] ≦ 10.0 × ^{10 -4} preferable. As the phosphorus compound, phosphoric acid or its ester (mono-, di- and tri-ester) derived from phosphoric acid or its ester is preferable, and specifically, trimethyl phosphate, triethyl phosphate, triphenyl phosphate. And tris-2-hydroxyethyl phosphate and the like.

  The phosphorus compound not only suppresses the deterioration of the color tone of the fiber due to the antimony compound, but also has an effect of suppressing thermal decomposition. When the content of the phosphorus compound in the fiber is less than the value determined by the formula (2), these effects become insufficient, and even if the formula (1) is satisfied, the color tone of the fiber is sufficiently improved, It may be difficult to improve the heat and humidity resistance, which is not preferable. On the other hand, when the content of the phosphorus compound in the fiber is larger than the value determined by the formula (2), for example, when the conductive fiber is composed of a polyester resin, the inside of the polyester system becomes acidic during the polycondensation reaction. As a result, an ether bond as a side reaction product is generated, which may cause a decrease in heat and humidity resistance and strength, which is not preferable.

  In the conductive fiber, by adjusting the content of the antimony compound and the phosphorus compound to an appropriate amount (amount shown by the formulas (1) and (2)), a fiber with improved wet heat resistance can be obtained. is there.

  Furthermore, in the present invention, from the viewpoint of further promoting the above effect, it is preferable that the contents of the antimony compound and the phosphorus compound satisfy the formula (3) at the same time.

(3) [P] / [Sb] ≧ 0.2

  As described above, since the phosphorus compound has the effect of suppressing the deterioration of the color tone of the fiber and the thermal decomposition action by the antimony compound, it is preferable to satisfy the formula (3) indicating the ratio with the antimony compound.

  When the conductive fiber of the present invention is composed of a polyester-based resin, in order to obtain a fiber having a low carboxyl end group concentration and excellent heat and heat resistance, in the polycondensation reaction of polyester, melt polymerization and solid phase polymerization I do. At this time, by adding the antimony compound and the phosphorus compound during the polycondensation reaction as described above, a polyester having a low carboxyl end group concentration and excellent heat and humidity resistance can be obtained only by melt polymerization.

  As described above, the method for adding the antimony compound and the phosphorus compound during the polycondensation reaction as a means for providing the conductive fiber with predetermined heat and moisture resistance has been described. A method of adding, a method of adjusting and changing polymerization conditions (amount of catalyst, temperature, etc.) at the time of melt polymerization may be employed. Needless to say, these methods can also reduce the carboxyl end group concentration of the polyester polymer, thereby realizing desired wet heat resistance.

  Specific examples of the terminal blocking agent include carbodiimide compounds such as N, N-bis (2,6-diisopropylphenyl) carbodiimide, and epoxy compounds such as phenyl glycidyl ether.

  Then, in the conductive fiber in the present invention, for example, the antimony compound and the phosphorus compound are included in one of the conductive component and the non-conductive component, thereby forming a polyester having a low carboxyl end group concentration, and the other component is It is also possible to obtain a polyester having a low carboxyl end group concentration by adding a terminal blocking agent as described above or adjusting the polymerization conditions.

  Here, the carboxyl end group concentration of the conductive fiber is preferably 25 geq / t or less, more preferably 20 geq / t or less, and further preferably 18 geq / t or less. When the carboxyl end group concentration is higher than 25 geq / t, it becomes inferior in heat-and-moisture resistance, and it tends to be unsatisfactory in terms of the decrease in conductivity performance and strength retention.

  The carboxyl end group concentration of the conductive fiber is obtained by dissolving 0.1 g of conductive fiber in 10 ml of benzyl alcohol, adding 10 ml of chloroform to this solution, and titrating with 1/10 N potassium hydroxide benzyl alcohol solution. .

  The conductive fiber may contain a compound other than the antimony compound and the phosphorus compound. In this case, for example, a titanium compound or a cobalt compound used as a polycondensation catalyst can be used.

  As the titanium compound, tetra n-butyl titanate, tetra n-propyl titanate, tetraisopropyl titanate, tetraethyl titanate, etc. are used, and tetra n-butyl titanate is preferable from the viewpoint of polycondensation catalytic activity and physical properties of the resulting fiber. .

  Examples of the cobalt compound include cobalt acetate, cobalt chloride, and cobalt benzoate, and cobalt acetate is preferred from the viewpoint of the physical properties of the resulting fiber.

    The content of the antimony compound and the phosphorus compound in the conductive fiber is determined by forming the molded product having a flat surface with a compression press machine after the conductive fiber is heated and melted on an aluminum plate. It can be measured by subjecting it to Denki Kogyo Co., Ltd. Model 3270) and quantitative analysis.

  Next, components constituting the conductive fiber will be described.

  The conductive fiber in the present invention may be composed of a uniform component only of a conductive component, but preferably adopts a composite form consisting of a non-conductive component and a conductive component, as a fiber-forming polymer of both components. In general, a polyester resin is used, and a conductive component is contained in a portion serving as a conductive component.

  In this case, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), etc. can be used as the polyester-based resin preferably used as the fiber-forming polymer, and these may be used singly or in a blend or copolymer. it can.

  Among these, as a copolymerization component, PET obtained by copolymerizing at least one component among isophthalic acid (IPA), cyclohexanedimethanol (CHDM), and cyclohexanedicarboxylic acid (CHDA) is preferable. The copolymerization amount is preferably 5 to 20 mol%, and more preferably 5 to 10 mol%.

  By applying PET copolymerized with the copolymer component as a non-conductive component, not only the compatibility with the conductive component is improved, but also the reaction temperature during the polycondensation reaction can be lowered, The temperature during spinning can also be lowered. Therefore, since the thermal decomposition reaction of the polymer at the time of polycondensation reaction and spinning can be suppressed, it is possible to obtain conductive fibers having excellent moisture and heat resistance.

  If the copolymerization amount is less than 5 mol%, the melting point does not drop much compared to ordinary PET, so it is difficult to lower the polycondensation reaction temperature and spinning temperature, and the effect of improving moist heat resistance tends to be insufficient. On the other hand, if the copolymerization amount exceeds 20 mol%, the amorphous region in the fiber increases, so not only the operability is deteriorated, but also the structure is susceptible to hydrolysis reaction, so that the heat and humidity resistance is likely to be lowered. It is not preferable.

  On the other hand, also for the conductive component, a polyester-based resin is suitable as the fiber-forming polymer as with the non-conductive component. As mentioned above, examples of the polyester-based resin include PET, PBT, and the like. Of course, these can be used alone or blended or copolymerized.

  In this case, it is preferable to use PBT as the polyester resin. This is because PBT is a resin having a very high crystallinity, which reduces the number of alignment defects of the conductive particles, and can maximize the performance of the conductive particles. Furthermore, by containing a specific copolymer component in the PBT, the content of the conductive particles can be increased, and the area contributing to further improvement of the conductive performance is increased.

  Even in the case of PBT, the copolymer component is preferably IPA, CHDM, CHDA, etc., and these may be used alone or in combination. Thereby, the compatibility (surface wettability) between the conductive component and the conductive particles can be improved, the mixing amount of the conductive particles can be increased, and excellent conductive performance can be exhibited. Furthermore, the flexibility of the polymer is improved, the spinning and drawing process can be performed smoothly, and the conductive performance can be uniform in the length direction.

  Further, when one or more of the above-mentioned CHDM, CHDA, and IPA are used in combination as the copolymer component, the copolymerization amount is preferably 5 to 55 mol% in any case, and more preferably 10 to 50 mol%. If the copolymerization amount is less than 5 mol%, the effect of improving the compatibility (surface wettability) with the conductive particles as described above, the effect of improving the flexibility of the polymer, and the effect of improving the durability may be insufficient. Yes, not preferred. On the other hand, if it exceeds 55 mol%, the polymer itself becomes completely amorphous, and thus it is difficult to disperse the conductive particles in the polymer.

  Examples of the conductive particles contained in the conductive component include conductive carbon black, metal powder (silver, nickel, copper, iron, tin, or alloys thereof), copper sulfide, copper iodide, zinc sulfide, sulfide. Examples thereof include metal compounds such as cadmium. In addition, a small amount of antimony oxide is added to tin oxide, or a small amount of aluminum oxide is added to zinc oxide to form conductive particles.

  Furthermore, it is also possible to use a conductive particle obtained by coating the surface of titanium oxide with tin oxide and mixing and baking antimony oxide. Among them, preferred is conductive carbon black (acetylene black, ketjen black, etc.) that is generally used for improving the performance of conductive fibers and does not hinder polymer fluidity compared to other metal particles.

  The particle diameter of the conductive particles is not particularly limited, but the average particle diameter is preferably 1 μm or less. When it exceeds 1 μm, the dispersibility of the conductive particles in the polymer tends to be deteriorated, and the fiber tends to have a deteriorated conductive performance and high elongation property.

  The content of the conductive particles in the conductive component may be appropriately selected depending on the type of conductive particles, conductive performance, particle diameter, particle chain-forming ability, and characteristics of the polymer used. It is preferable to set it as -50 mass%, More preferably, it is 10-40 mass%. If the content is less than 5% by mass, the conductive performance may be insufficient. If the content exceeds 50% by mass, it is difficult to disperse the conductive particles in the polymer.

  In addition, when adopting the above-described composite fiber as the conductive fiber, it is preferable to consider the compatibility with the conductive component from the viewpoint of preventing the peeling of both components. It is preferably formed from a resin.

  And since it is preferable that the antimony compound and the phosphorus compound are contained in the conductive fiber in the present invention as described above, naturally the same compound is contained in the conductive component and the non-conductive component. It is preferable. However, since the said compound is not an essential component, the aspect in which the said compound is contained only in one of an electroconductive component and a nonelectroconductive component is not excluded at all. For example, when a specific amount of the compound is contained with respect to the non-conductive component, cracks are less likely to occur in the conductive component even after repeated wet heat treatment, and the loss and dropout of the conductive particles are less likely to occur. It can be set as the conductive fiber which has no heat-and-moisture resistance performance. In particular, as the exposure of the conductive component to the fiber surface increases, the conductive component of the fiber surface is more likely to be damaged by wet heat treatment. In such a case, both components have a specific amount of antimony compound and phosphorus compound. It is good to contain.

  And in both components, as long as the effects are not impaired, waxes, polyalkylene oxides, various surfactants, dispersants such as organic electrolytes, antioxidants, ultraviolet absorbers, etc. Stabilizers, colorants, pigments, fluidity improvers, and other additives can also be added.

  Next, the mixed yarn used for the woven or knitted fabric of the present invention will be described.

  In the present invention, it is necessary to use the above-mentioned conductive fiber as a mixed yarn with a fiber other than the conductive fiber, instead of using the conductive fiber alone. This is because when conductive fibers are used alone, the conductive fibers are generally poor in stretchability, but the conductive fibers pop out on the surface of the woven or knitted fabric. Because it ends up. In addition, since conductive fibers are often inferior in strength and elongation characteristics as compared with general fibers, if the conductive fibers jump out on the surface of the woven or knitted fabric, they are easily cut and the desired conductive performance cannot be obtained. Therefore, when using conductive fibers, they are preferably fixed to other fibers, and from this point, mixed yarn is adopted in the present invention. Furthermore, in the present invention, it is necessary not to form a woven or knitted fabric only with the mixed yarn, but also to include a mixed yarn and other yarns. This is because blended yarn alone is disadvantageous in terms of strength, manufacturing cost, and the like.

  Note that interlace processing using compressed air is common as the fiber mixing means.

  Arrangement of the mixed yarn in the woven or knitted fabric may be arbitrary. However, if the blended yarn is biased and arranged at a specific location in the knitted or knitted fabric, the conductive performance of the woven or knitted fabric tends to be biased. Is preferred. Specifically, it is preferable to arrange the mixed yarns in a lattice pattern at intervals of 10 mm or less, more preferably 5 mm or less.

  Moreover, the blended yarn needs to be thicker than the other yarns from the viewpoint of enhancing the conductive performance of the woven or knitted fabric. Specifically, the ratio (A / B) of the total fineness A of the mixed yarn and the total fineness B of the yarn other than the mixed yarn is 1.1 to 5.0. When the fineness ratio is less than 1.1, the conductive fibers exposed on the surface of the woven or knitted fabric are reduced, and stable conductive performance cannot be obtained. On the other hand, if the fineness ratio exceeds 5.0, the conductive fibers may be broken only by being slightly rubbed and worn when being made into clothing, and stable conductive performance cannot be maintained.

  Here, the area ratio of the conductive fibers exposed on the surface of the woven or knitted fabric is preferably 1 to 30% with respect to the total surface area of the woven or knitted fabric. If the area ratio of the conductive fibers is less than 1%, stable conductive performance cannot be obtained. On the other hand, if it exceeds 30%, stable conductive performance can be obtained, but the cost increases and the woven / knitted fabric obtained. Are unfavorable because they tend to have poor performance such as pilling and snacking.

  As the yarn other than the mixed yarn, basically any yarn can be used. Specific examples include natural fibers such as cotton and wool, regenerated fibers such as rayon, and synthetic fibers such as esters and nylon, which can be appropriately selected according to the purpose. Since the woven or knitted fabric of the present invention is often applied to uniform garments and the like worn in a clean room or the like, it is preferable to employ synthetic fiber filament yarn instead of spun yarn from the viewpoint of dust generation.

  At this time, as the polymer forming the synthetic fiber filament yarn, for example, polyethylene terephthalate, polybutylene terephthalate, polyoxyethoxybenzoate, polyethylene naphthalate, cyclohexane dimethylene terephthalate, and these polyesters as an additional portion, isophthalic acid, sulfo In addition to polyesters copolymerized with diol components such as isophthalic acid, propylene glycol, butylene glycol, cyclohexane dimethanol, and diethylene glycol, polyamides such as nylon-6, nylon-6.6, and aromatic nylon, polypropylene, acrylic, or polycarbonate A compound such as pololactone or polybutylene succinate. An aliphatic polyester compound is decomposed into water and the like. In the present invention, among these, polyester is preferably employed from the viewpoint of dimensional stability.

  Examples of the cross-sectional shape of the filament include a round cross section, a triangular cross section, a square cross section, a pentagon cross section, a flat cross section, a wedge-shaped cross section, a C-shaped cross section, an H-shaped cross section, an I-shaped cross section, and the like.

  The woven or knitted fabric of the present invention is constituted by using the yarn as described above, and the woven structure is not particularly limited. In the case of a woven fabric, for example, plain weave, twill weave, satin weave, entanglement For example, a circular knitting, a weft knitting, and a warp knitting can be employed.

The woven or knitted fabric of the present invention exhibits excellent electrical conductivity as described above, and can maintain such performance even after wet heat treatment. Specifically, the surface leakage resistance value in a state where the sewing part is sandwiched needs to be 1 × 10 ⁹ Ω or less both before and after the wet heat treatment at 121 ° C. for 25 hours. The surface leakage resistance value is measured according to JIS L 1094 “Reference Surface Leakage Resistance Measurement Method / Kringing Measurement Method”.

When the surface leakage resistance value is reduced, charging of the woven or knitted fabric can be suppressed. Therefore, the woven or knitted fabric is more suitable for clothing used in a clean room for manufacturing semiconductors, various IT-related devices and precision parts. In the case of the present invention, when the surface leakage resistance value exceeds 1 × 10 ⁹ Ω, the conductive performance of the woven or knitted fabric becomes insufficient. The lower limit of the surface leakage resistance value is not particularly limited, but if it is less than 1 × 10 ⁴ Ω, the conductive fiber must contain a large amount of conductive particles. Not only does it adversely affect the properties, but it may also hinder spinning and stretching, which is not preferable. From this point, as a result, the surface leakage resistance value is preferably 1 × 10 ⁴ to 1 × 10 ⁹ Ω before and after the wet heat treatment.

Claims (1)

A woven or knitted fabric comprising a mixed yarn composed of conductive fibers and other fibers and a yarn other than the mixed yarn, wherein the total fineness A of the mixed yarn and the yarn other than the mixed yarn The ratio (A / B) to the total fineness B is 1.1 to 5.0, and the surface leakage resistance value with the sewing part sandwiched is 1 both before and after the wet heat treatment at 121 ° C. for 25 hours. A woven or knitted fabric characterized in that it is 10 ⁹ Ω or less.