Antistatic warp-knitted fabric

Abstract

The present invention relates to a warp-knitted fabric having antistatic properties in any of the longitudinal, transverse and diagonal directions, and which can maintain the antistatic properties in any of the above directions effectively even if wearing or washing is repeated, and which can provide a workwear having stretchability and a good wearing feeling. The present invention relates to a warp-knitted fabric having antistatic properties, which is formed by knitting (a) a composite yarn comprising a conductive yarn and a first non-conductive yarn and (b) a second non-conductive yarn, characterized in that (1) the composite yarn is contained in the yarn of at least either of the surface and the back of the warp-knitted fabric formed by knitting; (2) the composite yarn has one or more stitches formed by overlapping the loops of the composite yarns adjacent to each other; (3) the variation value (MMD) of the surface friction in the transverse direction of the warp-knitted fabric is 0.01 to 0.10; and (4) the surface resistance values in the longitudinal, transverse and diagonal directions measured by IEC 61340-5-1 after washing 10 times are all 1.0 x 10 10 Ω or less. 10 Ω or less.

Description

Technical Field

[0001] This invention relates to antistatic warp-knitted fabrics suitable for wearing in environments requiring high antistatic properties, such as factories producing food, electrical products, and precision equipment, and to work garments made therefrom. Background Technology

[0002] Fabrics made from synthetic fibers typically possess excellent strength, durability, and low dust generation, and are widely used as workwear. In particular, high antistatic properties are required in operations involving electronic devices, components, or materials. However, synthetic fibers suffer from the problem of readily generating static electricity in low humidity conditions, which can easily damage workpieces during processing. Therefore, various antistatic fibers and fabrics have been developed as a solution to combat static electricity.

[0003] Currently, the antistatic properties of workwear used in the electronics industry are defined by quasi-international standards. More specifically, according to IEC 61340-5-1, 5-2, the preferred surface resistivity value is considered to be 1×10⁻⁶. 11 Below Ω. It should be noted that, as mentioned above, antistatic property refers to the excellent performance in preventing static electricity and other forms of charge.

[0004] Patent Document 1 describes an antistatic work garment that meets the required antistatic properties, suitable for workers handling electronic devices, electronic components, or electronic materials. The antistatic work garment described in Patent Document 1 is made by sewing together a fabric woven from conductive composite yarns containing conductive fibers into a mesh pattern.

[0005] However, while the antistatic workwear described in Patent Document 1 has excellent antistatic properties, it lacks stretchability and comfort as workwear because it is made of woven fabric. Furthermore, since the conductive composite yarn containing conductive fibers is woven into a mesh pattern, the antistatic properties in the diagonal direction are insufficient.

[0006] In addition, Patent Document 2 proposes a knitted fabric that has antistatic properties in any direction of the longitudinal, transverse, or diagonal direction.

[0007] However, in Patent Document 2, conductive fibers (monomers) are used directly. Therefore, during warping or knitting, the conductive fibers are prone to frequent breakage, making it difficult to obtain high-quality knitted fabric with good productivity. Consequently, the production of workwear is costly. Furthermore, the conductive fibers in this knitted fabric are prone to breakage during washing or wearing, resulting in poor durability of its antistatic properties.

[0008] As mentioned above, especially in workwear used in various businesses such as the electronics industry, due to the high frequency of wearing and washing, knitted fabrics with excellent antistatic properties that do not decrease even after repeated wearing and washing are required.

[0009] Existing technical documents

[0010] Patent documents

[0011] Patent Document 1: Japanese Patent Application Publication No. 2008-7869

[0012] Second Patent Document 2: Japanese Patent Application Publication No. 2005-344245 Summary of the Invention

[0013] The problem that the invention aims to solve

[0014] Therefore, the main objective of this invention is to solve the aforementioned problems and provide an antistatic warp-knitted fabric that is antistatic in any direction of the warp, transverse and diagonal of the fabric, and that the antistatic properties in any direction are highly maintained even after repeated wear or washing, and that work clothes with elasticity and good wearing comfort can also be obtained.

[0015] Methods for solving problems

[0016] In order to solve the above-mentioned problems, the inventors conducted in-depth research and discovered that the above-mentioned objectives could be achieved by using warp-knitted fabrics with a specific structure, thus completing the present invention.

[0017] That is, the present invention relates to the following antistatic warp-knitted fabric.

[0018] 1. An antistatic warp-knitted fabric, which is formed by knitting (a) a composite yarn comprising a conductive yarn and a first non-conductive yarn and (b) a second non-conductive yarn, characterized in that it satisfies the following conditions (1) to (4):

[0019] (1) The yarns on at least one side of the surface and back of the warp-knitted fabric contain composite yarns.

[0020] (2) The composite yarn has one or more stitches formed by the overlapping of loops of adjacent composite yarns.

[0021] (3) The variation value (MMD) of surface friction in the transverse direction of warp-knitted fabric is 0.01 to 0.10, and

[0022] (4) After 10 cleaning cycles, the surface resistivity values ​​in the longitudinal, transverse, and diagonal directions, as measured by IEC61340-5-1, were all 1.0 × 10⁻⁶. 10 Below Ω.

[0023] 2. The antistatic warp-knitted fabric according to 1 above, wherein the composite yarn is selected from at least one of the group consisting of (i) twisted yarn, (ii) core-spun yarn and (iii) cross-linked yarn.

[0024] 3. The antistatic warp-knitted fabric according to 1 or 2 above, wherein the content of conductive yarn in the total mass of the warp-knitted fabric is 0.5 to 10.0% by mass.

[0025] 4. The antistatic warp-knitted fabric according to any one of 1 to 3 above, wherein, after 100 washes, the surface resistivity values ​​in the longitudinal, transverse, and twill directions, as measured by IEC 61340-5-1, are all 1.0 × 10⁻⁶. 11 Below Ω.

[0026] 5. The antistatic warp-knitted fabric according to 1 above, wherein the difference (AB) between the maximum total fineness (A) of the total fineness of the yarns knitted into the stitches formed by the overlap of the loops of the composite yarns and the minimum total fineness (B) of the total fineness of the yarns knitted into other stitches is 200 dtex or less.

[0027] 6. The antistatic warp-knitted fabric according to any one of 1 to 5 above, wherein the stitches formed by the overlap of loops of the composite yarns are included in a proportion of one or more per 2 cm in the transverse direction of the warp-knitted fabric.

[0028] 7. The antistatic warp-knitted fabric according to any one of 1 to 6 above, which is used for clothing applications.

[0029] 8. A work garment comprising the antistatic warp-knitted fabric described in any one of 1 to 7 above.

[0030] It should be noted that, in this invention, "after 10 washes" specifically refers to the state after repeatedly performing 10 washes according to the conditions of the Japanese Industrial Standard "JIS L 0217 103" (Household Electric Washing Machine Method). That is, it refers to the state after performing a series of operations including "washing," "rinsing," and "drying" under the above conditions as one cycle, and continuously performing this cycle 10 times. Similarly, "after 100 washes" specifically refers to the state after repeatedly performing 100 washes according to the conditions of the Japanese Industrial Standard "JIS L0217 103" (Household Electric Washing Machine Method). That is, it refers to the state after performing a series of operations including "washing," "rinsing," and "drying" under the above conditions as one cycle, and continuously performing this cycle 100 times.

[0031] Invention Effects

[0032] The present invention provides an antistatic warp-knitted fabric that exhibits antistatic properties in any direction of the warp, transverse, and diagonal of the fabric. Furthermore, the antistatic properties in any direction can be effectively maintained even after repeated wearing or washing. In addition, work clothes with elasticity and good wearing comfort can be obtained.

[0033] That is, the antistatic warp-knitted fabric of the present invention not only exhibits excellent initial antistatic properties, but also maintains good antistatic properties even after repeated wear or washing. In particular, the antistatic properties of the antistatic warp-knitted fabric of the present invention can also maintain the values ​​specified by quasi-international standards.

[0034] Furthermore, the antistatic warp-knitted fabric of the present invention is a knitted fabric, and therefore has superior elasticity compared to woven fabrics. In other words, the present invention achieves such high antistatic properties while retaining the original characteristics of knitted fabrics.

[0035] Furthermore, in the antistatic warp-knitted fabric of the present invention, the composite yarn has small unevenness and a smooth knitted fabric surface, thus providing clothing with a good wearing feel.

[0036] The antistatic warp-knitted fabric of the present invention, with these characteristics, can be suitable for use in various businesses that require methods to deal with static electricity, such as the electronics industry, and provides excellent comfort when worn. Attached Figure Description

[0037] Figure 1 This is a knitting pattern diagram illustrating one embodiment of the knitting structure of a "composite yarn comprising conductive yarn and a first non-conductive yarn" in the antistatic warp-knitted fabric of the present invention.

[0038] Figure 2This is a knitting pattern diagram illustrating another embodiment of the knitting structure of the antistatic warp-knitted fabric of the present invention, which is a "composite yarn comprising a conductive yarn and a first non-conductive yarn".

[0039] Figure 3 A knitting diagram illustrating the knitting structure of the "composite yarn containing conductive yarn and a first non-conductive yarn" in the warp-knitted fabric of Comparative Example 3.

[0040] Figure 4 This is a diagram illustrating an example of a cross-section of the conductive synthetic fiber used in the antistatic warp-knitted fabric of the present invention, wherein... Figure 4 A represents an embodiment in which a portion of the outer periphery of a conductive synthetic fiber has an exposed conductive polymer portion. Figure 4 B indicates an embodiment in which an exposed portion of conductive polymer is present on the entire outer periphery of the conductive synthetic fiber. Detailed Implementation

[0041] The antistatic warp-knitted fabric of the present invention is a warp-knitted fabric formed by knitting (a) a composite yarn containing conductive yarn and a first non-conductive yarn and (b) a second non-conductive yarn, characterized in that it satisfies the following conditions (1) to (4):

[0042] (1) The yarns on at least one side of the surface and back of the warp-knitted fabric contain composite yarns.

[0043] (2) The composite yarn has one or more stitches formed by the overlap of loops of adjacent composite yarns.

[0044] (3) The variation value (MMD) of surface friction in the transverse direction of warp-knitted fabric is 0.01 to 0.10, and

[0045] (4) After 10 cleaning cycles, the surface resistivity values ​​in the longitudinal, transverse, and diagonal directions, as measured by IEC61340-5-1, were all 1.0 × 10⁻⁶. 10 Below Ω.

[0046] The antistatic warp-knitted fabric of the present invention is formed by knitting (a) a composite yarn comprising a conductive yarn and a first non-conductive yarn and (b) a second non-conductive yarn.

[0047] First, the conductive yarn will be explained. The conductive yarn mainly functions to give the antistatic warp-knitted fabric of this invention its antistatic properties.

[0048] As conductive yarn, synthetic fibers composed of conductive polymers (conductive synthetic fibers) are preferred. A conductive polymer is generally a material obtained by combining conductive microparticles with a thermoplastic resin used to form the fiber. That is, a resin composition containing a thermoplastic resin and conductive microparticles can be used as the conductive polymer.

[0049] There are no limitations on the conductive particles; examples include powders of carbon materials such as conductive carbon black, various powders, and powders of metals or their compounds such as copper sulfide, zinc sulfide, and copper iodide. Conductive carbon black is preferred. The size of the conductive particles can also be appropriately set according to the fiber size, etc., and there are no particular limitations. Furthermore, the content of the conductive particles can also be appropriately set according to the desired conductivity, and therefore there are no particular limitations.

[0050] As thermoplastic resins, for example, polyolefin polymers such as polyethylene and polypropylene, polyamide polymers such as nylon 6, nylon 66, nylon 4, and nylon 12, and polyester polymers such as polyethylene terephthalate, polybutylene terephthalate, and polytetramethylene terephthalate can be used. Among these, considering heat resistance and other factors, at least one of polyester polymers and polyamide polymers is preferred.

[0051] As a conductive synthetic fiber, it can be a fiber formed from a single conductive polymer, but preferably a fiber having a composite cross-sectional shape consisting of a conductive polymer portion formed from a conductive polymer and a non-conductive polymer portion formed from a thermoplastic resin that does not contain conductive particles. In this case, the aforementioned thermoplastic resin can be used in either the conductive polymer portion or the non-conductive polymer portion.

[0052] If the content of conductive particles is increased to improve conductivity, there is a tendency to impair the strength or feel of the resulting fiber. However, by forming fibers with a composite cross-sectional shape as described above, the strength or feel can be well maintained. As for the shape of the composite cross-section, in order to improve conductivity, it is preferable that the conductive polymer is exposed on the fiber surface in the cross-sectional shape of the single fiber.

[0053] In this regard, the cross-section of the conductive synthetic fiber is illustrated in... Figure 4 . Figure 4 The conductive synthetic fiber 10 shown in Figure A includes a conductive polymer portion 10a and a non-conductive polymer portion 10b. As described above, it is preferable that the conductive polymer portion 10a is exposed on the surface of the conductive synthetic fiber. As an indicator of the degree of exposure, it is expressed as the ratio of the exposed portion of the conductive polymer portion (the sum of arcs C1, C2, C3, and C4) to the outer perimeter C of the conductive synthetic fiber [(C1+C2+C3+C4) / C]×100 (%). Figure 4 The conductive synthetic fiber 10' shown in B includes a conductive polymer portion 10'a and a non-conductive polymer portion 10'b. Since the conductive polymer portion is exposed throughout the entire periphery of the conductive synthetic fiber 10', its proportion is 100%.

[0054] In this invention, the exposed portion of the conductive polymer portion preferably accounts for more than 30% of the outer perimeter, more preferably more than 50% of the outer perimeter, and most preferably 100% of the outer perimeter.

[0055] In this invention, commercially available products can also be used as conductive yarns (especially conductive yarns with composite cross-sectional shapes). Examples include "Clacarbo" (trade name) manufactured by Kuraray Co., Ltd., "Belltron" (trade name) manufactured by KB SEIREN Co., Ltd., "LUANA" (trade name) manufactured by Toray Industries, Ltd., and "MEGANA" (trade name) manufactured by Unitika Trading Co., Ltd.

[0056] Typically, by placing conductive yarn on the surface of knitted fabric, good results can be obtained according to the surface resistivity values ​​of IEC 61340-5-1 and 5-2. However, conductive yarn is usually not only fine in texture but also weak in strength. Therefore, when used alone, it is prone to yarn breakage during warping and weaving processes, making stable implementation difficult. In view of this, in the present invention, since the conductive yarn is used together with a first non-conductive yarn to produce composite yarns such as twisted yarn, blended yarn, and core-spun yarn, the above-mentioned problems do not occur.

[0057] Next, the non-conductive yarns (first non-conductive yarn and second non-conductive yarn) will be described. The non-conductive yarn is preferably a yarn obtained from a thermoplastic resin. For example, it can be formed from a resin composition that does not contain conductive particles but contains a thermoplastic resin. There are no particular limitations on the thermoplastic resin; for example, polyolefin polymers such as polyethylene and polypropylene, polyamide polymers such as nylon 6, nylon 66, nylon 4, and nylon 12, and polyester polymers such as polyethylene terephthalate, polybutylene terephthalate, and tetramethylene terephthalate can be used. Among these, polyester polymers are preferred from the perspective of heat resistance, etc.

[0058] As a non-conductive yarn, textile yarns obtained from long or short fibers of multifilaments or monofilaments, obtained by melt spinning a resin composition containing a thermoplastic resin as described above, can be suitable. By using long fibers as the fibers constituting the antistatic warp-knitted fabric of the present invention, less dust is generated from the fibers. Among them, polyester long fibers are preferred. As polyester long fibers, for example, long fibers obtained by melt spinning a resin composition containing a polyester polymer can be suitable.

[0059] Furthermore, there are no restrictions on the use of non-conductive yarns, as long as the yarn uses the aforementioned thermoplastic resin. Additionally, non-conductive yarns can be core-sheath type, side-by-side type, or other composite fibers. In the case of composite fibers, in addition to composite fibers using two or more different types of resins, composite fibers using two or more resins of the same type but different compositions and property values ​​can also be used.

[0060] In the case of conductive synthetic fibers with a composite cross-section, the combination of the polymer forming the conductive polymer portion and the polymer forming the non-conductive polymer portion can be a combination of polymers of the same type or a combination of polymers of different types. In this invention, from the perspective of compatibility, a combination of polymers of the same type is preferred. Among them, at least one of polyester polymers, polyamide polymers, etc., is preferably used as the thermoplastic resin.

[0061] Next, the composite yarn formed by the conductive yarn and the first non-conductive yarn will be described. As the form of the composite yarn, it is preferably any one of twisted yarn, core-spun yarn, or cross-woven yarn.

[0062] There are no restrictions on the type of yarn used. For example, yarn obtained by twisting the conductive yarn and the first non-conductive yarn using a known twisting machine such as a ring twister is preferred, with a twist of 200 to 700 t / M.

[0063] There are no restrictions on the type of core-spun yarn. For example, a single-core or double-core-spun yarn with a twist of 200 to 700 t / M, using a conductive yarn as the core yarn and a first non-conductive yarn as the sheath yarn, is preferred.

[0064] There are no restrictions on the type of interlaced yarn. For example, it is preferable to use a conductive yarn as the core yarn, a first non-conductive yarn as the float yarn, and an interlaced yarn with an interlacing degree of 30 to 100 interlacing points / m formed by using air force to tie the two yarns together with an interlaced nozzle.

[0065] In this invention, by using conductive yarn together with non-conductive yarn in the form of a composite yarn as described above, rather than using conductive yarn alone, yarn breakage of the conductive yarn can be reduced. This improves the workability of the resulting knitted fabric and effectively maintains the quality and antistatic properties of the fabric.

[0066] There are no restrictions on the fineness of the individual fibers of the conductive yarn used in the composite yarn, but it is preferably 4 to 20 dtex. There are no particular restrictions on the total fineness, but it is preferably 20 to 35 dtex.

[0067] The fineness of the single fiber of the first non-conductive yarn used in the composite yarn is not limited, but is preferably 1 to 5 dtex. The total fineness is not limited, but is preferably 30 to 120 dtex. The total fineness of the composite yarn is not limited, but is preferably 50 to 150 dtex.

[0068] The antistatic warp-knitted fabric of the present invention is a warp-knitted fabric formed by knitting the aforementioned composite yarn and a second non-conductive yarn. To fully exhibit antistatic properties, the composite yarn is included in the yarn on at least one side of the surface and back of the warp-knitted fabric. That is, the antistatic warp-knitted fabric of the present invention is configured such that the composite yarn is exposed on the surface and / or back of the antistatic warp-knitted fabric. The degree of exposure is as described below, provided that the surface resistivity values ​​in the longitudinal, transverse, and diagonal directions, measured according to IEC61340-5-1, are 1.0 × 10⁻⁶ after 10 washes. 10 The surface resistivity should be below Ω. However, the more the composite yarn is exposed, the more easily it wears away, which can lead to a decrease in conductivity. Therefore, it is desirable that the antistatic warp-knitted fabric of the present invention has the above-mentioned surface resistivity value while satisfying the variation value (MMD) shown below being in the range of 0.01 to 0.10.

[0069] Here, there is no limitation on the fineness of the single fiber of the second non-conductive yarn, as long as it meets the (AB) described later, and it is usually preferred to be 1 to 10 dtex. In addition, the total fineness is usually preferred to be 20 to 150 dtex.

[0070] In the antistatic warp-knitted fabric of the present invention, the composite yarn has one or more stitches formed by the overlapping of loops of adjacent composite yarns (hereinafter also referred to as "stitch X"). Regarding this point, using... Figure 1 Please provide an explanation. Figure 1 A knitting pattern diagram illustrating one embodiment of the antistatic warp-knitted fabric of the present invention. Figure 1 A, Figure 1 In the knitting diagram shown in B, for adjacent composite yarns (a) and (b), the overlapping of the loops of the two composite yarns forms two consecutive stitches (circular symbols) in the longitudinal direction. In this invention, the arrangement of stitch X is not particularly limited, such as... Figure 1 As shown, stitch X (e.g.) Figure 1 A, Figure 1 The circular symbol portion in B can be formed continuously, as in other implementations, such as Figure 2 As shown, stitch X (e.g.) Figure 2 The circular symbol portion in the middle) can also be separated by other stitches (hereinafter also referred to as "stitch Y"). (For example) Figure 2 It is formed by the square symbol part in the middle.

[0071] In composite yarns, without stitch X, conductivity exists in the longitudinal (wale) direction but not in the transverse (course) direction, resulting in high surface resistance in both the transverse and diagonal directions. In contrast, in this invention, each composite yarn (all composite yarns) has one or more stitch X, allowing the conductive yarns within the composite yarn to contact each other and conduct electricity. Therefore, conductivity exists not only in the longitudinal direction but also in the transverse and diagonal directions, resulting in lower surface resistance.

[0072] In the antistatic warp-knitted fabric of the present invention, it is preferable that the stitch X is included at a ratio of 5 or more per 10 cm in the longitudinal direction of the warp-knitted fabric (5 stitches / 10 cm), and more preferably at a ratio of 10 or more per 10 cm (10 stitches / 10 cm). This ensures higher conductivity.

[0073] Furthermore, the antistatic warp-knitted fabric of the present invention has the above-described properties. Figure 1 A, Figure 1 B or Figure 2 The structure shown is preferably such that there is one or more stitches X per 2 cm (1 stitch / 2 cm) in the transverse direction of the knitted fabric. More preferably, there are 2 to 5 stitches X per 2 cm (2 to 5 stitches / 2 cm) in the transverse direction of the warp-knitted fabric.

[0074] The variation value (MMD) of surface friction in the transverse direction of the antistatic warp-knitted fabric of the present invention is preferably in the range of 0.01 to 0.10, and more preferably 0.015 to 0.06. Furthermore, the variation value (MMD) of surface friction in the longitudinal direction is also preferably within the above range.

[0075] This value represents the degree of unevenness of the warp-knitted fabric. By making the variation value of surface friction (MMD) in the transverse direction 0.0J to 0.10, the warp-knitted fabric has less unevenness and is a smooth warp-knitted fabric. At the same time, it can make the surface resistivity value measured by IEC61340-5-1 low.

[0076] Furthermore, due to its smooth surface with minimal unevenness, the conductive yarn is less prone to breakage even during wear due to friction, thus maintaining antistatic properties more reliably. It should be noted that the difficulty of breakage of the conductive yarn due to friction during wear can be evaluated using a snag test, with a snag test rating preferably of 3 or higher, and more preferably 4 or higher. In addition, the smooth surface with minimal unevenness also results in a warp-knitted fabric with excellent wearing comfort.

[0077] For surface resistivity values ​​measured according to IEC 61340-5-1, there is a tendency that the more exposed conductive yarns on the surface of the knitted fabric, forming larger protrusions, the greater the current flowing between the electrodes, and the lower the surface resistivity. In other words, the smoother the surface of the knitted fabric, the smaller the current flowing between the electrodes, and the higher the surface resistivity. Therefore, if the variation in surface friction (MMD) is less than 0.01, the surface resistivity values ​​in the longitudinal, transverse, and diagonal directions tend to be higher.

[0078] For the antistatic warp-knitted fabric of the present invention, by making the variation value of surface friction (MMD) in the transverse direction meet 0.01 to 0.10, it becomes an antistatic warp-knitted fabric with low surface resistance, durability against friction during wear, and excellent wearing comfort.

[0079] It should be noted that, in this invention, the variation value (MMD) of surface friction of warp-knitted fabric is determined as follows: The warp-knitted fabric used as the sample is measured using a KES surface property testing machine (manufactured by Kato Tech Co., Ltd., "KESFB2-A") under the conditions of a load MIU: 50 gf, contact pressure: 10 gf, sample tension: 20 gf / cm, and speed: 1 mm / sec.

[0080] To ensure that the variation value (MMD) of surface friction of the antistatic warp-knitted fabric of the present invention is 0.01 to 0.10, it is preferable to reduce the unevenness of the knitted fabric. More specifically, the antistatic warp-knitted fabric of the present invention is a warp-knitted fabric formed by knitting a composite yarn formed from conductive yarn and a first non-conductive yarn, and a second non-conductive yarn. The difference (AB) between the total total fineness of the stitch with the largest total fineness of the yarns woven into each stitch (maximum total fineness: A) and the total total fineness of the stitch with the smallest total fineness of the yarns woven into each stitch (minimum total fineness: B) is generally preferably 200 dtex or less, more preferably 150 dtex or less, and most preferably 100 dtex or less. It should be noted that the lower limit value of the above-mentioned (AB) can be set to, for example, 5 dtex, but is not limited thereto.

[0081] In particular, in the antistatic warp-knitted fabric of the present invention, the maximum total fineness is often the total fineness of the yarns already knitted into stitch X. Therefore, the difference (AB) between the maximum total fineness (A) of the yarns already knitted into stitch X and the minimum total fineness (B) of the yarns already knitted into other stitches (stitch Y) is preferably 200 dtex or less. The lower limit of (AB) may be, for example, 5 dtex, but is not limited thereto.

[0082] It should be noted that, regarding the maximum total fineness (A) and the minimum total fineness (B), for example, when each stitch X has a different total fineness, the total fineness of the stitch Xmax with the largest total fineness is taken as A. Similarly, when each stitch Y has a different total fineness, the total fineness of the stitch Ymin with the smallest total fineness is taken as B.

[0083] Regarding this point, Example 1 described later is given as an example. The stitch (stitch X) formed by L1, L2(A), and L3(A) is the coarsest, with a maximum total fineness of 188 dtex. On the other hand, the stitch (stitch Y) formed by L1, L2(B), and L3(B) is the finest, with a minimum total fineness of 168 dtex. Therefore, the value of (AB) above becomes 188 - 168 = 20 dtex.

[0084] For the antistatic warp-knitted fabric of the present invention, by using the yarn described above for knitting, not only is the initial antistatic property excellent, but the antistatic property is also excellent after 10 washes, and preferably excellent after 100 washes. Specifically, after 10 washes, the surface resistivity values ​​in the longitudinal, transverse, and diagonal directions, as measured by IEC61340-5-1, are 1.0 × 10⁻⁶. 10 Ω or less, wherein, preferably 1.0 × 10 Ω 9 Ω or less, and more preferably 1.0 × 10 Ω. 8 Below Ω.

[0085] Furthermore, the initial longitudinal, transverse, and diagonal surface resistivity values ​​measured according to IEC61340-5-1 are preferably 1.0 × 10⁻⁶. 10 Ω or less, wherein, more preferably, is 1.0 × 10 Ω. 9 Below Ω, especially the optimal value is 1.0 × 10⁻⁶. 8 Below Ω.

[0086] Furthermore, the surface resistivity values ​​in the longitudinal, transverse, and oblique directions after 100 cleaning cycles, as measured by IEC61340-5-1, are preferably 1.0 × 10⁻⁶. 11 Ω or less, wherein, more preferably, is 1.0 × 10 Ω. 10 Below Ω, especially the optimal value is 1.0 × 10⁻⁶. 9 Below Ω.

[0087] It should be noted that for surface resistivity values ​​measured according to IEC61340-5-1, the lower the value, the better the antistatic properties of the knitted fabric. However, this can sometimes cause problems with fiber strength and hand feel. Therefore, there is no particular limitation on the lower limit of the surface resistivity value, but 1.0 × 10⁻⁶ is preferred. 4 Around Ω.

[0088] In addition, it is preferable that not only the longitudinal direction, transverse direction and diagonal direction fall within the above-mentioned range, but also the surface resistance values at the initial stage, after 10 washes and after 100 washes between the seams when sewing the warp-knitted fabric all satisfy the above-mentioned range.

[0089] In the present invention, the surface resistance value is measured according to IEC61340-5-1. More specifically, "PORSTAT Resistance System PRS-801" is used as the measuring device, and the surface resistance value is measured under the conditions of a measurement environment of 23°C × 12% RH and a measurement spacing of 250 mm. In addition, the washing conditions comply with the Japanese Industrial Standards JIS L 0217 Method 103.

[0090] The antistatic warp-knitted fabric of the present invention has the above-mentioned antistatic property, and the content of the conductive yarn in the warp-knitted fabric is usually preferably 0.5 to 10 mass%, particularly more preferably 1 to 8 mass%. When the content of the conductive yarn is less than 0.5 mass%, it is difficult to obtain the target antistatic property of the present invention. On the other hand, when it exceeds 10 mass%, there is a tendency to impair the strength or hand feel of the warp-knitted fabric, and the cost may also be high.

[0091] For the conductive warp-knitted fabric of the present invention, after weaving, various processes such as dyeing processing, water-absorbing processing, and electrification processing can be performed, for example.

[0092] The antistatic warp-knitted fabric of the present invention can be suitably used for clothing applications, and the type of clothing is not particularly limited. In addition to upper-body garments, lower-body garments and the like, it also includes socks, gloves, scarves, hats and the like.

[0093] Moreover, the antistatic warp-knitted fabric of the present invention can be used as work clothing used in various businesses represented by the electronics industry, and can be used for work clothing applications used in clean room applications requiring excellent antistatic properties, food processing applications, and general electrical work applications. For the above-mentioned work clothing, the antistatic warp-knitted fabric of the present invention can be used at least in a part thereof, and can be obtained by using ordinary knitting techniques, sewing techniques and the like.

[0094] Examples

[0095] Examples and comparative examples are shown below to more specifically describe the features of the present invention. However, the scope of the present invention is not limited to the Examples. It should be noted that various values in the Examples are measured in the following manner.

[0096] 〔Snagging〕

[0097] According to the Japanese Industrial Standard JIS L 1058 2011 D-3, four test pieces were collected from the obtained warp-knitted fabric, and the test results of the four pieces were judged and the average value was calculated. A grade of 3 or above was considered acceptable.

[0098] [Variation value of surface friction]

[0099] The measurements were performed using the methods described above. It should be noted that both longitudinal and transverse variation values ​​(MMD) were measured.

[0100] [Surface resistivity]

[0101] The surface resistivity of the obtained warp-knitted fabric in the longitudinal, transverse, and diagonal directions was measured using IEC 61340-5-1, initially, after 10 washes, and after 100 washes. Washing was performed according to JIS L 0217 103. Then, the obtained warp-knitted fabric was prepared to be cut into rectangles with a length of 35 cm and a short length of 30 cm under the conditions shown in (a) to (c) below, resulting in three samples.

[0102] (a) The longer side is vertical and the shorter side is horizontal.

[0103] (b) The longer side is horizontal and the shorter side is vertical.

[0104] (c) The longer side is diagonal, and the shorter side is diagonal.

[0105] Then, following the order of (a), (b), and (c), two points are sewn together using double stitches on one side of the long side of (a) and (b) and two points are sewn together using double stitches on one side of the long side of (b) and (c) to form sample (d).

[0106] For the longitudinal surface resistivity, the sample in (a) was used, and measurements were taken at intervals of 25 cm along the long side.

[0107] For the lateral surface resistance value, the sample in (b) was used, and measurements were taken at intervals of 25 cm along the long side.

[0108] For the oblique surface resistivity value, the sample (c) is used, and the measurement is performed at a measurement interval of 25 cm along the long side.

[0109] For the surface resistivity between seams, the sample (d) was used, and the measurements were taken at 60cm intervals along the short side, with two seams sewn together by double stitches through a single-sided flange.

[0110] Example 1

[0111] (Use of yarns)

[0112] L1 yarn guide reed (original Japanese text: 箴): Polyester multifilament (56dtex / 36f) formed from polyethylene terephthalate (second non-conductive yarn)

[0113] L2 yarn guide reed: (A): Composite yarn formed from the first non-conductive yarn and conductive yarn shown below (twist: Z twist, 400T / m doubled and twisted yarn)

[0114] First non-conductive yarn… Polyester multifilament (33dtex / 12f) formed from polyethylene terephthalate

[0115] Conductive yarn… "Belltron" manufactured by KB SEIREN Co., Ltd. (33dtex / 6f, the conductive polymer in the sheath accounts for 100% of the outer perimeter)

[0116] (B): Polyester multifilament (56dtex / 36f) formed from polyethylene terephthalate (second non-conductive yarn)

[0117] One (A) is arranged every 6 courses, and the rest are arranged with (B) to achieve full set. (Original Japanese text: (A)を6コ一スに1本配列し、それ以外は(B)を配列し、フルセシトとした。)

[0118] L3 yarn guide reed: (A) uses the same composite yarn as (A) of the L2 yarn guide reed, (B) uses the same polyester multifilament (second non-conductive yarn) as (B) of the L2 yarn guide reed, and the arrangement is performed in the same manner as the L2 yarn guide reed.

[0119] (Knitting structure)

[0120] The back yarn is arranged in the L1 yarn guide reed, the middle yarn is arranged in the L2 yarn guide reed, and the front yarn is arranged in the L3 yarn guide reed. Using these yarns, a tricot warp knitting machine (manufactured by Karl MAYER Co., Ltd.) with a gauge of 28 is used to Figure 1 knit to form a warp-knitted fabric with the structure shown in A (only the L2 yarn guide reed and L3 yarn guide reed are illustrated).

[0121] For the obtained warp-knitted fabric, using a circular flow dyeing tester, a surfactant (manufactured by Nicca Chemical Co., Ltd., SUNMORL (original Japanese text: サンモ一ル) FL) is used at a concentration of 1g / L, and relaxation scouring is performed at 90°C for 30 minutes.

[0122] Next, using the same circular flow dyeing tester as described above, water absorption and dyeing processing is performed at 130°C for 30 minutes, and then finish setting (original Japanese text: 仕上げセツト) is performed to obtain an antistatic warp-knitted fabric.

[0123] Example 2

[0124] For the arrangement of L2 and L3 reeds, one yarn (A) is arranged in 14 loop rows, and the rest are arranged with yarn (B), and then fully threaded through to form... Figure 1 The fabric shown in B (only L2 and L3 reeds are illustrated) is knitted into a warp-knitted fabric in the same manner as in Example 1. The obtained warp-knitted fabric is then subjected to water absorption, dyeing, and finishing processes in the same manner as in Example 1 to obtain an antistatic warp-knitted fabric.

[0125] Example 3

[0126] Regarding the arrangement of L2 and L3 reeds, one reed (A) is arranged in 14 loop rows, and the (B) yarn is not arranged. Otherwise, the operation is the same as in Example 2 to knit a warp-knitted fabric. The obtained warp-knitted fabric is subjected to water absorption, dyeing, and finishing to obtain an antistatic warp-knitted fabric.

[0127] Example 4

[0128] (Use of yarn)

[0129] L2 reed, L3 reed: (A): The same composite yarn (twisted yarn) as in Example 1.

[0130] (B): The same polyester multifilament yarn (56 dtex / 36f) as in Example 1 (second non-conductive yarn)

[0131] Arrange one coil (A) in six horizontal rows of coils, and the rest in rows (B), and thread them through the coils completely.

[0132] (Knitted structure)

[0133] The center yarn is placed on reed L2, and the front yarn is placed on reed L3. Using these yarns, a size 28 Trico warp knitting machine (made by Karl Mayer) is used. Figure 2 The structure shown is knitted to form a warp-knitted fabric. Following the same procedure as in Example 1, the obtained warp-knitted fabric is subjected to water absorption, dyeing, and finishing processes to obtain an antistatic warp-knitted fabric.

[0134] It should be noted that the obtained warp-knitted fabric contains stitches X at a ratio of 50 stitches per 10cm (50 stitches / 10cm) in the longitudinal direction.

[0135] Comparative Example 1

[0136] L1 reed: Polyester multifilament (84 dtex / 36f) formed from polyethylene terephthalate (second non-conductive yarn)

[0137] L2 reed: (A): A composite yarn formed by the first non-conductive yarn and the conductive yarn shown below (twist (Z twist) 400T / m)

[0138] The first non-conductive yarn...is a polyester multifilament (84 dtex / 36f) formed from polyethylene terephthalate.

[0139] Conductive yarn… "Belltron" (33 dtex / 6f, conductive polymer in the sheath accounts for 100% of the outer circumference) manufactured by KB SEIREN.

[0140] (B): No yarn arrangement.

[0141] L3 reed: (A) Use the same yarn as L2 reed (A), (B) Do not arrange the yarn, and make the same arrangement as L2 reed.

[0142] In addition, the process is the same as in Example 1, to knit a warp-knitted fabric. Similarly to Example 1, the obtained warp-knitted fabric is subjected to water absorption, dyeing, and finishing processes to obtain an antistatic warp-knitted fabric.

[0143] Comparative Example 2

[0144] L2 and L3 reeds (A) use only conductive yarn and do not form a composite yarn with the first non-conductive yarn. Otherwise, the process is the same as in Example 3, and the warp-knitted fabric is formed. The obtained warp-knitted fabric is subjected to water absorption, dyeing, and finishing processes as in Example 1 to obtain an antistatic warp-knitted fabric.

[0145] Comparative Example 3

[0146] like Figure 3 As shown, in L2 and L3, the structure of each composite yarn is changed to not have stitch X. Otherwise, the operation is the same as in Example 3 to knit a warp-knitted fabric. The obtained warp-knitted fabric is subjected to water absorption, dyeing and finishing processes in the same way as in Example 1 to obtain an antistatic warp-knitted fabric.

[0147] Experimental Example 1

[0148] The property values ​​of the antistatic warp-knitted fabrics obtained in Examples 1-4 and Comparative Examples 1-3 are shown in Table 1.

[0149] [Table 1]

[0150]

[0151] As shown in Table 1, the warp-knitted fabrics obtained in Examples 1 to 4 meet all the conditions (1) to (4) specified in this invention. They have low surface resistivity based on IEC61340-5-1 and excellent washability of surface resistivity. In addition, they have less surface roughness and high snagging evaluation, thus maintaining high antistatic performance.

[0152] On the other hand, regarding the warp-knitted fabric obtained in Comparative Example 1, it can be seen that due to the large surface unevenness, the condition (3) is not met, and therefore the snagging evaluation is low. That is, the risk of breakage of the conductive yarn is high, and there is concern that repeated wear may lead to a decrease in antistatic properties. In addition, due to the large surface unevenness, it may become a warp-knitted fabric with poor wearing comfort.

[0153] As for the warp-knitted fabric obtained in Comparative Example 2, since it uses a single conductive yarn (not a composite yarn formed by conductive and non-conductive yarns), its antistatic properties decrease with repeated washing, and it does not meet the condition (4). In addition, the conductive yarn breaks during warping and knitting, resulting in poor operability.

[0154] For the warp-knitted fabric obtained in Comparative Example 3, the composite yarns do not have stitches X with each other, which does not satisfy condition (2). Therefore, the surface resistance values ​​(initial values) in the transverse and oblique directions are high, which does not satisfy condition (4).

Claims

1. An antistatic warp-knitted fabric, comprising (a) a composite yarn including a conductive yarn and a first non-conductive yarn and (b) a second non-conductive yarn, characterized in that, It satisfies the following conditions (1) to (4): (1) The yarns on at least one side of the surface and back of the warp-knitted fabric contain composite yarns. (2) The composite yarn has one or more stitches formed by the overlapping of loops of adjacent composite yarns. (3) The variation value of surface friction in the transverse direction of warp-knitted fabric, i.e., MMD, is 0.01 to 0.10, and (4) After 10 cleaning cycles, the surface resistivity values ​​in the longitudinal, transverse, and oblique directions, as measured by IEC61340-5-1, were all 1.0 × 10⁻⁶. 10 Below Ω.

2. The antistatic warp-knitted fabric according to claim 1, wherein, The composite yarn is selected from at least one of the group consisting of (i) twisted yarn, (ii) core-spun yarn and (iii) cross-linked yarn.

3. The antistatic warp-knitted fabric according to claim 1, wherein, The content of conductive yarn in the total mass of warp-knitted fabric is 0.5% to 10.0% by mass.

4. The antistatic warp-knitted fabric according to claim 1, wherein, After 100 cleaning cycles, the surface resistivity values ​​in the longitudinal, transverse, and diagonal directions, measured according to IEC61340-5-1, were all 1.0 × 10⁻⁶. 11 Below Ω.

5. The antistatic warp-knitted fabric according to claim 1, wherein, The difference AB between the maximum total fineness A of the yarns that have been woven into the stitches formed by the overlapping loops of the composite yarns and the minimum total fineness B of the yarns that have been woven into other stitches is less than 200 dtex.

6. The antistatic warp-knitted fabric according to claim 1, wherein, The stitches formed by the overlap of loops of the composite yarns in the transverse direction of the warp-knitted fabric are such that there is more than one stitch every 2 cm.

7. The antistatic warp-knitted fabric according to any one of claims 1 to 6, for use in clothing.

8. A work garment comprising the antistatic warp-knitted fabric as described in any one of claims 1 to 6.

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