JP2012207328A - Protective fabric excellent in contact cool feeling and cut resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a protective fabric excellent in cut resistance, and excellent in cool feeling when worn.SOLUTION: The protective fabric excellent in contact cool feeling and cut resistance is composed of a duplex coat yarn constituted by covering a core yarn with a filament yarn selected from a para-aramid fiber, a wholly aromatic polyester fiber, and a polyparaphenylenebenzobisoxazole fiber, as a sheath fiber 1(2a), and further covering the core yarn with a high strength polyethylene fiber as a sheath fiber 2(2b). The sheath fiber 1 is preferably a crimped yarn of a para-aramid fiber.

Description

  The present invention relates to a protective fabric that is light and flexible, unprecedented, and has a refreshing feeling and excellent cut resistance when worn.

  A light and flexible fabric can be obtained by selecting the material and basis weight of the fibers to be used, but a fabric having cut resistance has not been easily obtained. In order to obtain a fabric with excellent cut resistance, particles such as colloidal silica are mixed in the resin and processed into resin, or other fibers with excellent cut resistance are knitted and used. Means have been taken, and fibers having high tensile strength represented by aramid fibers, wholly aromatic polyester fibers, high-strength polyethylene fibers, etc., and particularly high Young's modulus have been used.

  In particular, para-aramid fibers are widely used as protective fabrics having excellent cut resistance. For example, it is preferably used as protective clothing such as fire fighting clothes, racing suits for automobile races, work clothes for iron making or welding, and gloves. Above all, para-aramid fibers, which have both high heat resistance and heat resistance, are used in sports clothing, work clothes, ropes, tire cords, etc. that require tear strength and heat resistance, and because they are difficult to cut with a knife, they are wounded. It is also used for work gloves for prevention.

  As the para-aramid fiber, polyparaphenylene terephthalamide (PPTA) fiber is well known. For example, US Pat. No. 3,767,756 and Japanese Patent Publication No. 56-128312 describe a method for producing PPTA fiber. It is disclosed. On the other hand, meta-aramid fibers do not have cut resistance and high tensile strength like para-aramid fibers, but their heat resistance makes them suitable for fire fighting clothes, heat insulating filters, heat-resistant dust filters, and electrical insulating materials. It is used.

  Conventionally, when producing textile products such as clothing products using these heat-resistant and high-performance filament yarns, the fibers have only been used in the form of filament yarns and spun yarns that are not stretchable. However, even if a non-stretchable yarn such as filament yarn or spun yarn is processed into a fabric to produce a clothing product such as a fire fighting suit, racing suit or work clothes, the stretchability of the clothing product is inferior. When the apparel product is worn, there are disadvantages that it is not comfortable to wear and is difficult to act. Similarly, conventional work gloves made from non-stretchable yarns have a poor feeling of wear and have been a cause of lowering work efficiency.

  In view of such market demands, many studies and proposals have been made on methods for imparting crimps to heat-resistant and highly functional filament yarns. For example, a method in which a low elastic modulus fiber is mixed with a high elastic modulus fiber such as a para-aramid fiber and crimped by an indentation method (Patent Document 1). In the case of a system aramid fiber, after a false twist crimping process using a non-contact heater heated to 390 ° C. or more and less than 460 ° C., a method of imparting crimp by relaxing heat treatment (Patent Document 2), para system aramid fiber, etc. A method of performing a heat setting by hydrothermal treatment at 130 to 250 ° C. or a dry heat treatment at 140 to 390 ° C., and then untwisting the twist after adding twist to the heat-resistant and high-performance fiber yarn (Patent Document 3) Etc. are known.

  Also, protective gloves with excellent combustion resistance, heat resistance, and stretchability can be obtained by forming a woven or knitted fabric using covered yarn made by winding crimped yarn around elastic fiber with stretchability. It has also been reported (Patent Documents 4 to 6).

  However, in protective gloves obtained by the above method, although good heat resistance and cut resistance can be obtained, the thermal conductivity of the aramid fiber itself is low, so the cool feeling when worn is poor and it is easy to get stuffy There were drawbacks. Protective gloves using high-strength polyethylene fibers, on the other hand, are characterized by their high thermal conductivity, so they have a refreshing feeling when worn and are not easily stuffy even when worn for a long time, but their cut resistance is not as good as that of aramid fibers. A sufficient cut resistance was not obtained (for example, Patent Document 7).

Japanese Patent Laid-Open No. 1-192839 (Claims) JP-A-6-280120 (Claims, [0024]) JP 2001-248027 A (Claims) JP 2004-011060 A (Claims) JP 2003-193345 A (Claims) JP 2003-193314 A (Claims) Japanese Patent No. 4513929 (Claims)

  In view of the background of such prior art, the present invention is intended to provide a protective fabric that is excellent in cut resistance and excellent in a refreshing feeling when worn.

The present invention employs the following means in order to solve such problems. That is, the present invention is as follows.
(1) A sheath yarn 1 is covered with a filament yarn selected from para-aramid fiber, wholly aromatic polyester fiber, and polyparaphenylenebenzobisoxazole fiber as sheath yarn 1, and further as sheath yarn 2, A protective fabric excellent in contact cooling feeling and cut resistance using a double-coated yarn formed by covering a high-strength polyethylene fiber.
(2) The protective fabric according to (1), wherein the sheath yarn 1 is a crimped yarn of a para-aramid fiber.
(3) The protective fabric according to (1) or (2), wherein the core yarn is an elastic fiber.

  The protective fabric of the present invention has high cutability, which has not been obtained in the past, is excellent in a refreshing feeling when worn, and has good fit when used for gloves and workability when worn.

It is a schematic side view which shows an example of the double covering yarn used by this invention. It is a schematic diagram which shows an example of the manufacturing method of the double covering yarn used by this invention.

  Hereinafter, the details of the protective fabric of the present invention will be described. FIG. 1 is a schematic side view showing an example of the double coated yarn of the present invention. The double coated yarn (A) is covered around the core yarn (1) by the sheath yarn 1 (2a) and further covered by the sheath yarn 2 (2b).

  In the double coated yarn used for knitting the protective fabric of the present invention, elastic fibers having elasticity are preferably used as the core yarn from the viewpoint of imparting elasticity to the coated yarn. The elastic fiber is preferably a polyurethane elastic fiber having high stretchability. Such polyurethane-based elastic fibers are not particularly limited in cross-sectional shape, and may be circular or flat, and the fibers may be monofilaments or welded multifilaments. .

  The fineness of the elastic fiber is preferably in the range of 11 to 940 dtex, and more preferably in the range of 22 to 350 dtex. If it is less than 11 dtex, it will cause thread breakage in the covering and glove knitting process, and it will not be possible to obtain a product with sufficient fit when worn on the glove. On the other hand, if it exceeds 940 dtex, it will not match the gauge number of the glove knitting machine. Moreover, it is preferable that breaking elongation is 300% or more, and when it is less than 300%, sufficient stretchability cannot be obtained when a glove is formed.

  In the double coated yarn used in the protective fabric of the present invention, the sheath yarn 1 is selected from para-aramid fibers, wholly aromatic polyester fibers, and polyparaphenylene benzobisoxazole fibers. Each of these fibers has a high tensile strength of 1.75 N / tex or more as measured by JIS L 1013 8.5 as a property of the raw yarn, and has a decomposition start temperature higher than 400 ° C. and heat resistance. It is an excellent one. When the tensile strength is less than 1.75 N / tex, the fabric using the coated yarn cannot be imparted with high durability such as bending resistance and wear resistance, and is not suitable for a protective fabric. It will be a thing. Preferably, the tensile strength is about 1.75 to 3.5 N / tex.

  Here, as the para-aramid fiber, polyparaphenylene terephthalamide fiber (manufactured by Toray DuPont, trade name “Kevlar”) and copolyparaphenylene-3,4′-diphenyl ether terephthalamide fiber (manufactured by Teijin Techno Products) , Trade name “Technora”). Examples of the wholly aromatic polyester fiber include a product name “Vectran” manufactured by Kuraray Co., Ltd., and examples of the polyparaphenylene benzobisoxazole fiber include a product name “Zylon” manufactured by Toyobo Co., Ltd. Among these fibers, a para-aramid fiber is preferable, and a polyparaphenylene terephthalamide fiber is particularly preferable because it has high strength, a high elastic modulus, and excellent cut resistance.

  The fineness of the sheath yarn 1 may be appropriately selected in consideration of the surface appearance, stretchability, texture and the like according to the purpose of use. The fineness of the sheath yarn 1 is preferably in the range of 20 to 1600 dtex depending on the purpose of use.

  Furthermore, the single fiber fineness of the sheath yarn 1 is preferably in the range of 0.1 to 10 dtex, more preferably in the range of 0.4 to 5 dtex, depending on the application. If it is less than 0.1 dtex, the yarn-making efficiency is low and the cost increases. If it exceeds 10 dtex, the rigidity is high and it is not suitable for a glove that requires flexibility.

  The sheath yarn 1 is preferably a filament yarn that hardly generates fluff and dust, and a crimped yarn obtained by crimping the filament yarn is preferably used from the viewpoint of imparting flexibility to the protective fabric. The crimped yarn is dried using, for example, a twisting process in which a high-strength fiber such as para-aramid fiber is twisted, followed by wet heat treatment using high-temperature high-pressure steam or high-temperature high-pressure water, or an electric heater. It manufactures by implementing the heating process which heat-processes, and also the untwisting process which unwinds the said twist. Examples of the production method include a continuous false twisting method or a batch (non-continuous) production method, and more preferably, the crimped yarn has good bulkiness and the fibers of the crimped yarn are scattered. The continuous false twisting method is used from the point that the untwisted state is good.

  More specifically, a manufacturing method using the continuous false twisting method will be described.

In this false twisting method, the yarn drawn from the supply yarn cheese by the feed roller is wound up on a take-up bobbin through a heater, a false twist device, and a take-up roller. For example, a false twisting spindle can be equipped with a spinner in a false twisting device. When a spinner is wound around a pin of the spinner and the spindle is rotated, the yarn between the feed roller and false twisting spindle is subjected to, for example, S twisting. The twisted yarn is heat set (dry heat treatment) with a heater, and the twist is reversed by adding, for example, a Z twist opposite to the above between the false twist spindle and the take-up roller. When it is unwound (untwisting step), it becomes a crimped yarn. A space between the false twisting device and the take-up roller is a cooling zone, which is preferably left to air cooling. In addition to the above-mentioned false twist spindle, the false twisting method is a method in which the yarn is brought into contact with the inner wall of a cylinder that rotates at high speed, the outer periphery of a disk, or the surface of a belt that runs at high speed, and the false twist is applied by friction, i.e. A friction disk or the like is used.

  In the production method by the false twisting method, when producing a crimped yarn of para-aramid fiber, the moisture content is preferably 20% or less, more preferably 15%, as the para-aramid fiber before false twisting. In the following, it is particularly preferable to use 1 to 10%. If the moisture content before twisting exceeds 20%, heat is not efficiently transferred to the yarn in the dry heat treatment and the heat setting effect cannot be obtained, so that it is difficult to obtain a good crimped yarn. If the moisture content is less than 1%, the yarn may fibrillate due to rubbing of the yarn path guide or the like.

  When crimped yarn is used as the sheath yarn 1, when the sheath yarn 1 is a para-aramid fiber, the stretch / elongation rate measured according to the JIS L 1013 8.11 A method is preferably 20% or more. More preferably, it is 20 to 70%. If the stretch / extension rate is 20% or more, the fabric is excellent in stretchability and flexibility, so that the workability is good. On the other hand, if it is 70% or less, the fabric is well harmonized with the core yarn, particularly elastic fibers. As a result, the appearance quality is improved without unevenness.

  In the double-coated yarn used in the protective fabric of the present invention, the sheath yarn 2 is made of high-strength polyethylene fiber that is excellent in thermal conductivity in terms of contact cooling. The high-strength polyethylene fiber has a high thermal conductivity of 5 W / m · K (watt per meter per kelvin) or higher. When the thermal conductivity is less than 5 W / m · K, it becomes impossible to impart a feeling of contact cooling to the fabric using the coated yarn. Preferably, the thermal conductivity is about 8 to 80 W / m · K. Here, examples of the high-strength polyethylene fiber include Toyobo Co., Ltd., trade names “Dyneema” “Tunuga”, DSM Corp., trade name “Dyneema”, Honeywell Corp., trade name “Spectra”, and the like.

  The high-strength polyethylene fiber has a high tensile strength of 1.2 N / tex or more as a property of the raw yarn measured according to JIS L 1013 8.5. When the tensile strength is less than 1.2 N / tex, the fabric using the coated yarn cannot be imparted with high durability such as high bending resistance and wear resistance, and is not suitable for a protective fabric. Become. Preferably, the tensile strength is about 1.2 to 3.5 N / tex.

  The sheath yarn 2 is preferably a filament yarn that is less likely to generate fluff and dust. Either a filament raw yarn or a crimped yarn obtained by crimping the filament raw yarn may be used, but the filament raw yarn is preferably used from the viewpoint of efficiently obtaining a cool contact feeling in the form of the yarn.

  The fineness of the sheath yarn 2 may be appropriately selected in consideration of the surface appearance, stretchability, texture, etc., depending on the purpose of use, but is the same as or more than the fineness of the sheath yarn 1, and a range of 50 to 1600 dtex. It is preferable to do this. If it is smaller than the fineness of the sheath yarn 1, it is necessary to increase the number of twists of the cover ring of the sheath yarn 2 in order to improve the covering, which causes problems in terms of overload to the covering processing equipment and production efficiency.

  In the double coated yarn of the present invention, from the viewpoint of obtaining excellent stretchability, first, the sheath yarn 1 covers the periphery of the core yarn in a single layer, and the sheath yarn 2 covers the periphery of the covering yarn in a single layer. To do. In this covering yarn, the sheath yarn 1 used for the first covering is called the lower twisted yarn, and the sheath yarn 2 used for the double covering is called the upper twisted yarn. The twisting direction of the upper twisted yarn cover ring is preferably applied in the direction opposite to the twisted direction of the lower twisted yarn cover ring in order to cancel the torque.

  Specifically, a sheathed yarn 1 is covered with para-aramid fiber, wholly aromatic polyester fiber or polyparaphenylene benzobisoxazole fiber, which has high strength and excellent heat resistance, around a polyurethane-based elastic fiber as a core yarn. Further, the sheath yarn 2 is a double-covered yarn covering high-strength polyethylene fibers having high thermal conductivity, and the double-covered yarn is used as a fabric such as a knitted fabric or a woven fabric. Thus, the protective fabric of the present invention having excellent cut resistance can be obtained.

  Next, the manufacturing method of the double coated yarn of this invention is demonstrated. FIG. 2 is a schematic diagram showing an example of a method for producing a double-coated yarn of the present invention.

  In covering, a commercially available covering machine or the like is preferably used.

  FIG. 2 is an example in which the sheath yarn 1 (2a) is covered around the core yarn (1) in a single layer and the sheath yarn 2 (2b) is covered in a single layer. In FIG. 2, the polyurethane elastic fiber used as the core yarn (1) is positively fed by the rolling yarn feeding roller (3), predrafted with the feed roller (4), and then the feed roller (4) and the deli Draft further between Verirollers (11).

  The sheath thread 1 (2a) and the sheath thread 2 (2b) are wound around the H bobbin by a commercially available high-speed winder and then installed on the lower spindle (5) and the upper spindle (7) as shown in FIG. Then, it is wound around the core yarn (1) by rotating the spindle to form the double coated yarn (A).

  The obtained double-coated yarn (A) is wound around cheese (14) by a take-up roller (13).

  At this time, the twist direction of the cover ring of the sheath yarn 2 is preferably applied in the direction opposite to the twist direction of the cover ring of the sheath yarn 1 in order to cancel the torque.

  When covering the sheath yarn 1 and the sheath yarn 2 with the core yarn, the number of twists of the covering of the sheath yarn 1 and the sheath yarn 2 may be appropriately selected depending on the fineness of the sheath yarn, but is represented by the following formula (1). The value of the twist coefficient (K) is about 500 to 5,000, preferably about 1,000 to 3,000.

K = T × D ^1/2 (1)
[However, T represents the number of twists (times / m) of the cover ring, and D represents the fineness (tex). ]

  Further, the number of twists of the cover ring of the sheath yarn 2 is preferably equal to or less than the number of twists of the cover ring of the sheath yarn 1. If it is larger than the number of twists of the cover ring of the sheath yarn 1, it is not good in terms of overloading to the covering processing equipment and production efficiency.

  When the twist coefficient (K) is too small, particularly when the core yarn is a polyurethane elastic fiber, the amount of fibers per unit area of the sheath yarn 1 and the sheath yarn 2 is reduced when a fabric such as a woven fabric or a knitted fabric is formed, The cut resistance of the sheath yarn 1 and the good thermal conductivity of the sheath yarn 2 are not reflected.

  On the other hand, if the twist coefficient (K) is too large, the number of windings of the sheath yarn 1 with respect to the core yarn is increased, so that the core yarn and the sheath yarn constituting the coated yarn, the gap between the sheath yarns, and the individual sheath yarns. Since the interval between the fibers becomes narrow, the flexibility of the fabric is inferior.

  When covering the sheath yarn 1 and the sheath yarn 2 with the core yarn, the draft ratio of the core yarn is about 1.5 to 5.0, preferably 2.0 to 4.0. If it is less than 1.5, it will be difficult to cover the sheath yarn in the covering step, and if it exceeds 5.0, it will be easy to break the yarn in the covering step, resulting in poor productivity. The draft magnification in this case refers to the entire draft, that is, the draft between the yarn feeding roller (3) and the delivery roller (11) in FIG.

  In the present invention, the protective fabric using the double-coated yarn is a knitted fabric, a woven fabric, a braided fabric or other braided fabric, a knitted fabric such as a rope, or a woven fabric and a string-like material. It can be produced by a known processing apparatus.

Cool contact feeling of the protective fabric of the present invention, qmax obtained by the test method described below is not less 0.08 W / cm ² or more, preferably 0.10 W / cm ^2. When qmax is less than 0.08 W / cm ² , a sufficient refreshing feeling cannot be obtained.

  Further, the cut resistance of the protective fabric of the present invention is such that the cutting force obtained by the JIS T 8052: 2005 test method is 4N or more, preferably 6N or more. When the cutting force is less than 4N, sufficient cutting resistance performance cannot be obtained.

  A rubber or resin coating material can be applied to the surface of the protective fabric as long as the contact cooling sensation and cut resistance are not impaired.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

  The evaluation method of each physical property was based on the following method.

[Fineness]
JIS L 1013: 2010 Chemical fiber filament yarn test method 8.3 Measured by B method (simple method).

[Tensile strength]
The tensile strength was measured by JIS L 1013: 2010 chemical fiber filament yarn test method 8.5.

[Elasticity]
JIS L 1013: 2010 Chemical fiber filament yarn test method 8.11. The stretch / elongation rate was measured by A method. As a pretreatment before the measurement, the measurement sample was skeined and wrapped in gauze, followed by a hot water treatment at 90 ° C. for 20 minutes, followed by natural drying at room temperature.

[Contact sensation]
The feeling of contact cooling of the fabric was made by Kato Tech Co., Ltd., KES-F7, Thermolab II, environmental temperature 20 ° C., humidity 65% RH, contact pressure 98 cN / cm ² , contact area 9 cm ² (3 cm × 3 cm) The peak value qmax (W / cm ² ) of the heat transfer amount was measured under the measurement conditions. In addition, the larger the value of qmax, the better the cool feeling of contact.

[Cut resistance]
JIS T 8052: 2005 Protective clothing-Mechanical properties-Cutting force (N) was measured by a cutting resistance test method for sharp objects. It should be noted that the greater the value of the cutting force, the more difficult it is to cut.

[Example 1]
Polyparaphenylene terephthalamide fiber (hereinafter referred to as PPTA) having a total fineness of 440 dtex, a single fiber fineness of 1.7 dtex, a tensile strength of 2.0 N / tex, and a moisture content of 7% (made by Toray DuPont Co., Ltd., trade name “Kevlar” "(Registered trademark)" filament yarn was subjected to false twisting in which the twisting direction was S direction to obtain a crimped yarn of PPTA filament. The stretched elongation rate of the obtained crimped yarn was 22%.
Using the covering process shown in FIG. 2, a polyurethane elastic fiber having a fineness of 117 dtex and a breaking elongation of 530% (trade name “Lycra” (registered trademark), manufactured by Toray Operontex Co., Ltd.) is used as the core yarn. In addition, the crimped yarn of the para-aramid fiber obtained above is spirally wound as the sheath yarn 1 (bottom twisted yarn), and the total fineness is 440 dtex, the single fiber fineness is 1.1 dtex, the tensile strength as the sheath yarn 2 (upper twisted yarn) 2.7 N / tex, thermal conductivity 50 W / m · K high-strength polyethylene fiber (manufactured by Toyobo Co., Ltd., trade name “Dyneema” (registered trademark), SK60) filament yarn crimped with para-aramid fiber It was wound in a spiral shape in the opposite direction to the yarn, and a coated yarn was obtained under the following processing conditions.

Spindle speed: 5000rpm
Draft of core yarn: Covering twist number T of 3.0 times sheath yarn 1 (bottom twisted yarn) and its twist direction: 350 times / m, Covering twist number T of S direction sheath yarn 2 (upper twisted yarn) and its twist Direction: 350 times / m, Z direction

One of the obtained coated yarns was supplied to a 13 gauge type glove knitting machine (Shimane Seiki Seisakusho Co., Ltd.), and a glove having a weight of 26 g / sheet and a palm weight per unit area of 360 g / m ² was knitted. This glove has a soft and voluminous texture, is highly stretchable and has a good fit, cool contact feeling (qmax: 0.17 W / cm ² ), cut resistance (cutting force: 6.5 N) Both were excellent.

[Example 2]
High-strength polyethylene fiber having a total fineness of 440 dtex, a single fiber fineness of 1.2 dtex, a tensile strength of 1.4 N / tex, and a thermal conductivity of 10 W / m · K (trade name, manufactured by Toyobo Co., Ltd.) A glove was produced in the same manner as in Example 1 except that a filament thread of “Tunuga” (registered trademark) was used.
The glove thus obtained has a weight of 25.5 g / sheet, a weight per unit area of 350 g / m ² , has a soft and voluminous texture, is highly stretchable, has a good fit, and has a cool feeling of contact (qmax : 0.14 W / cm ² ) and cut resistance (cutting force: 7.2 N).

[Comparative Example 1]
As the sheath yarn 2 (top twisted yarn), a filament yarn of nylon fiber (manufactured by Toray Industries, Inc.) with a total fineness of 470 dtex, a tensile strength of 0.7 N / tex, and a thermal conductivity of 1.5 W / m · K is used. A glove was produced in the same manner as in Example 1 except that the number T was set to 335 times / m.

The glove thus obtained has a weight of 27 g / sheet, a palm weight of 370 g / m ² , has a soft and voluminous texture, is highly stretchable, and has a cut resistance (cutting force: 6.0 N). ) Was excellent, but lacked contact cooling sensation (qmax: 0.06 W / cm ² ) and was inferior in cooling sensation.

  Since the protective fabric of the present invention is excellent in refreshing feeling and cut resistance, it is useful as a protective glove for work or a protective glove for sports in fisheries, agriculture, food industry, medical care, high-tech industry and the like.

A: Coated yarn 1: Core yarn 2a: Sheath yarn 1
2b: sheath thread 2
3: Rolling roller 4: Feed roller 5: Lower spindle 6: Lower belt 7: Upper spindle 8: Upper belt 9: H bobbin 10: Snell guide 11: Delivery roller 12: Guide bar 13: Take-up roller 14: cheese

Claims (3)

  Around the core yarn, a sheath yarn 1 is covered with a filament yarn selected from para-aramid fiber, wholly aromatic polyester fiber, polyparaphenylene benzobisoxazole fiber, and further, a sheath yarn 2 is used as a high-strength polyethylene fiber. A protective fabric excellent in contact cooling feeling and cut resistance using a double-coated yarn formed by covering the material.   The protective fabric according to claim 1, wherein the sheath yarn 1 is a crimped yarn of para-aramid fiber. The protective fabric according to claim 1 or 2, wherein the core yarn is an elastic fiber.