Woven fabrics and heat protective clothing

Abstract

To provide a woven or knitted fabric excellent in flame retardancy, heat insulating property and comfort, and to provide thermal protective clothing.SOLUTION: There is provided a woven or knitted fabric comprising a spun yarn obtained by blending a meta-type wholly aromatic polyamide fiber with a para-type wholly aromatic polyamide, wherein the woven or knitted fabric has a basis weight of 100-200 g / m2 and a thickness of 0.6 to 1.1 mm under a load of 7 g / cm2.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a woven or knitted fabric and a heat protective garment that are excellent in flame retardancy, heat insulation and comfort. [Background technology]

[0002] Knitted fabrics have excellent elasticity and are therefore used as sportswear and workwear. For heat protection purposes, knitted fabrics using flame-retardant fibers and having excellent heat shielding properties have been proposed (see, for example, Patent Documents 1 to 4).

[0003] However, while these technologies have excellent heat insulation properties, they also have high heat retention properties, which means that heat does not easily escape when worn, making them less comfortable and increasing the risk of heat stroke.In particular, the international standard ISO21942 has been established in recent years for the so-called station wear worn by firefighters under their firefighting suits, but the requirements include heat resistance to evaluate heat loss from the body and water vapor transmission resistance, and the above-mentioned prior art was not sufficient to meet these requirements. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2010-242239 A [Patent Document 2] JP 2019-090120 A [Patent Document 3] JP 2019-127657 A [Patent Document 4] JP 2020-193422 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in consideration of the above background, and an object of the present invention is to provide a woven or knitted fabric and a heat protective garment that are excellent in flame retardancy, heat shielding properties, and comfort. [Means for solving the problem]

[0006] The present inventors have conducted extensive research to achieve the above object and have thus completed the present invention.

[0007] Thus, according to the present invention, there is provided a woven or knitted fabric comprising a spun yarn in which meta-type wholly aromatic polyamide fiber and para-type wholly aromatic polyamide fiber are blended, the fabric having a basis weight of 100 to 200 g / m 2 , and 7g / cm 2 A woven or knitted fabric having a thickness under load of 0.6 to 1.1 mm is provided.

[0008] In this case, it is preferable that all of the following requirements (1) to (8) are satisfied. (1) In the flame resistance test specified in ISO 15025 Procedure A, all of the following are satisfied: a) No flame b) No flaming or molten falling objects c) No holes larger than 5 mm d) Residual light lasts for 2 seconds or less e) Afterflame lasts less than 2 seconds (2) In the heat resistance test specified in ISO 17493, the material satisfies all of the following conditions when exposed to 260 to 265°C for 5 minutes. a) Does not melt b) No dripping c) No flame d) Shrinkage rate is less than 10% (3) HTI in the flame exposure test specified in ISO 9151 24 is more than 4 seconds. (4) 20 kW / m as specified in ISO 6942 METHOD B 2 In a radiant heat exposure test with a heat flux of RHTI 24 is more than 7 seconds. (5) The dimensional change after five washes as specified in ISO 5077 is less than 8%. (6) The bursting strength specified in ISO 13938-1 or ISO 13938-2 is 50 cm 2If the pressure exceeds 100 kPa, the test piece is 7.3 cm 2 In this case, it exceeds 200 kPa. (7)Thermal resistance value specified in ISO 11092 is 0.055m 2 Less than K / W. (8) Water vapor transmission resistance value specified in ISO 11092 is 7m 2 Less than Pa / W. Effect of the Invention

[0009] According to the present invention, there are provided woven and knitted fabrics and heat protective clothing that are excellent in flame retardancy, heat insulation properties, and comfort. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. First, the spun yarn contains meta-type wholly aromatic polyamide fibers and para-type wholly aromatic polyamide fibers, which are blended together. Here, the meta-type wholly aromatic polyamide fiber is a fiber made of a polymer in which 85 mol % or more of the repeating units are m-phenylene isophthalamide. Such a meta-type wholly aromatic polyamide may be a copolymer containing a third component within the range of less than 15 mol %.

[0011] Such meta-type wholly aromatic polyamides can be produced by a conventionally known interfacial polymerization method, and the degree of polymerization of the polymer is preferably such that the intrinsic viscosity (IV) of the polymer, measured in an N-methyl-2-pyrrolidone solution having a concentration of 0.5 g / 100 ml, is in the range of 1.3 to 1.9 dl / g.

[0012] The meta-type wholly aromatic polyamide may contain an alkylbenzenesulfonate onium salt. Preferred examples of the alkylbenzenesulfonate onium salt include hexylbenzenesulfonate tetrabutylphosphonium salt, hexylbenzenesulfonate tributylbenzylphosphonium salt, dodecylbenzenesulfonate tetraphenylphosphonium salt, dodecylbenzenesulfonate tributyltetradecylphosphonium salt, dodecylbenzenesulfonate tetrabutylphosphonium salt, and dodecylbenzenesulfonate tributylbenzylammonium salt. Among them, dodecylbenzenesulfonate tetrabutylphosphonium salt or dodecylbenzenesulfonate tributylbenzylammonium salt is particularly preferred because it is easily available, has good thermal stability, and has high solubility in N-methyl-2-pyrrolidone.

[0013] In order to obtain a sufficient effect of improving dyeability, the content of the alkylbenzenesulfonic acid onium salt is preferably 2.5 mol % or more, and more preferably in the range of 3.0 to 7.0 mol %, based on the poly-m-phenyleneisophthalamide.

[0014] As a method for mixing poly-m-phenylene isophthalamide and an alkylbenzene sulfonate onium salt, a method for mixing and dissolving poly-m-phenylene isophthalamide in a solvent, and a method for dissolving an alkylbenzene sulfonate onium salt in the solvent, etc., may be used. The dope thus obtained is formed into fibers by a conventionally known method.

[0015] For the purpose of improving dyeability and resistance to fading, the polymer used for the meta-type wholly aromatic polyamide fiber may have an aromatic polyamide skeleton containing a repeating structural unit represented by the following formula (1) in which an aromatic diamine component different from the main structural unit of the repeating structure or an aromatic dicarboxylic acid halide component is copolymerized as a third component in an amount of 1 to 10 mol % relative to the total amount of the repeating structural units of the aromatic polyamide. -(NH-Ar1-NH-CO-Ar1-CO)- Formula (1) Here, Ar1 is a divalent aromatic group having a linking group in a meta-coordinated or non-parallel axial direction.

[0016] Also, it can be copolymerized as a third component, and specific examples of the aromatic diamines shown in formulas (2) and (3) include p-phenylenediamine, chlorophenylenediamine, methylphenylenediamine, acetylphenylenediamine, aminoanisidine, benzidine, bis(aminophenyl)ether, bis(aminophenyl)sulfone, diaminobenzanilide, diaminoazobenzene, etc. Specific examples of the aromatic dicarboxylic acid dichlorides shown in formulas (4) and (5) include terephthalic acid chloride, 1,4-naphthalenedicarboxylic acid chloride, 2,6-naphthalenedicarboxylic acid chloride, 4,4'-biphenyldicarboxylic acid chloride, 5-chloroisophthalic acid chloride, 5-methoxyisophthalic acid chloride, bis(chlorocarbonylphenyl)ether, etc.

[0017] H2N-Ar2-NH2...Formula (2) H2N-Ar2-Y-Ar2-NH2... formula (3) XOC-Ar3-COX...Formula (4) XOC-Ar3-Y-Ar3-COX...Formula (5) Here, Ar2 is a divalent aromatic group different from Ar1, Ar3 is a divalent aromatic group different from Ar1, Y is at least one atom or functional group selected from the group consisting of an oxygen atom, a sulfur atom, and an alkylene group, and X is a halogen atom.

[0018] The degree of crystallinity of the meta-type wholly aromatic polyamide fiber is preferably 5 to 35% in terms of good dye exhaustion and easy adjustment to a target color with less dye or under weak dyeing conditions, and more preferably 15 to 25% in terms of low surface uneven distribution of the dye, high resistance to discoloration, and dimensional stability required for practical use.

[0019] The amount of the remaining solvent in the meta-type wholly aromatic polyamide fibers is preferably 0.1 mass % or less (more preferably 0.001 to 0.1 mass %) so as not to impair the excellent flame retardant performance of the meta-type wholly aromatic polyamide fibers.

[0020] As such a meta-type wholly aromatic polyamide fiber, in order to obtain excellent light fastness, a spun-dyed meta-type wholly aromatic polyamide fiber as described in WO 2013 / 061901 is preferable.

[0021] That is, examples of pigments that can be used in the present invention include organic pigments such as azo pigments, phthalocyanine pigments, perinone pigments, perylene pigments, and anthraquinone pigments, and inorganic pigments such as carbon black, ultramarine blue, red iron oxide, titanium oxide, and iron oxide, but are not limited to these.

[0022] In addition, the method of mixing the meta-type wholly aromatic polyamide and the pigment may be, but is not limited to, a method of preparing an amide solvent slurry in which the pigment is uniformly dispersed in an amide solvent, and then adding the amide solvent slurry to a solution in which the meta-type wholly aromatic polyamide is dissolved in an amide solvent, or a method of directly adding a pigment powder to a solution in which the meta-type wholly aromatic polyamide is dissolved in an amide solvent.

[0023] The amount of pigment to be blended is 10.0% by mass or less, preferably 5.0% by mass or less, based on the meta-type wholly aromatic polyamide. If the amount of pigment added is more than 10.0% by mass, the physical properties of the resulting fiber may be deteriorated.

[0024] The meta-type wholly aromatic polyamide fibers as described above can be produced by the following method, and in particular, the crystallinity and the amount of remaining solvent can be adjusted to the above-mentioned ranges by the method described below. The polymerization method for the meta-type wholly aromatic polyamide polymer is not particularly limited, and for example, the solution polymerization method or interfacial polymerization method described in JP-B-35-14399, U.S. Pat. No. 3,360,595, JP-B-47-10863, etc. may be used.

[0025] The spinning solution is not particularly limited, but may be an amide-based solvent solution containing an aromatic copolyamide polymer obtained by the above-mentioned solution polymerization or interfacial polymerization, or may be a solution obtained by isolating the polymer from the above-mentioned polymerization solution and dissolving it in an amide-based solvent.

[0026] Examples of the amide solvent used here include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and dimethylsulfoxide, with N,N-dimethylacetamide being particularly preferred.

[0027] The copolymerized aromatic polyamide polymer solution obtained as described above is stabilized by further containing an alkali metal salt or an alkaline earth metal salt, and can be used at a higher concentration and at a lower temperature, which is preferable. The alkali metal salt and the alkaline earth metal salt are preferably 1% by mass or less, more preferably 0.1% by mass or less, based on the total mass of the polymer solution. In this case, it is preferable to contain a flame retardant such as the one described above.

[0028] In the spinning and coagulation step, the spinning solution (meta-type wholly aromatic polyamide polymer solution or spun-dyed meta-type wholly aromatic polyamide polymer solution) obtained above is spun into a coagulation solution and coagulated.

[0029] The spinning device is not particularly limited, and a conventionally known wet spinning device can be used. In addition, as long as it can perform stable wet spinning, there is no need to particularly limit the number of spinning holes, the arrangement state, the hole shape, etc. of the spinneret, and for example, a multi-hole spinneret for staple fibers having 1000 to 30000 holes and a spinning hole diameter of 0.05 to 0.2 mm may be used. The temperature of the spinning solution (meta-type wholly aromatic polyamide polymer solution) when it is spun out from the spinneret is suitably in the range of 20 to 90°C.

[0030] The coagulation bath used to obtain the fibers is an aqueous solution of an amide solvent, preferably NMP, containing substantially no inorganic salts and having a concentration of 45 to 60% by mass, with the bath temperature in the range of 10 to 50°C. If the concentration of the amide solvent (preferably NMP) is less than 45% by mass, the skin will be thick, which may reduce the washing efficiency in the washing step and make it difficult to reduce the amount of solvent remaining in the fibers. On the other hand, if the concentration of the amide solvent (preferably NMP) exceeds 60% by mass, uniform coagulation cannot be achieved even in the interior of the fibers, which also makes it difficult to reduce the amount of solvent remaining in the fibers. The appropriate immersion time of the fibers in the coagulation bath is in the range of 0.1 to 30 seconds.

[0031] Next, the film is stretched at a stretch ratio of 3 to 4 in a plastic stretching bath containing an amide solvent, preferably an aqueous solution of NMP with a concentration of 45 to 60% by mass, and the bath temperature is set in the range of 10 to 50° C. After stretching, the film is thoroughly washed by passing it through an aqueous solution of NMP with a concentration of 20 to 40% by mass at 10 to 30° C., and then through a warm water bath at 50 to 70° C. The washed fibers are subjected to a dry heat treatment at a temperature of 270 to 290° C., whereby meta-type wholly aromatic aramid fibers that satisfy the above ranges of the degree of crystallinity and the amount of remaining solvent can be obtained.

[0032] In the meta-type wholly aromatic aramid fiber, the fiber may be a long fiber (multifilament) or a short fiber. In particular, in order to blend with other fibers, a short fiber having a fiber length of 25 to 200 mm is preferable. The single fiber fineness is preferably in the range of 1 to 5 dtex.

[0033] Furthermore, as the para-type wholly aromatic polyamide fiber, paraphenylene terephthalamide fiber or coparaphenylene-3,4'-oxydiphenylene terephthalamide fiber is more preferable.

[0034] If meta-type wholly aromatic polyamide is used alone, there is a risk of holes being generated in the flame resistance test specified in ISO 15025 Procedure A. If para-type wholly aromatic polyamide is used alone, there is a risk of flame catching.

[0035] The blend ratio of the meta-type wholly aromatic polyamide fiber and the para-type wholly aromatic polyamide fiber is preferably 95 to 40% by weight of the meta-type wholly aromatic polyamide fiber based on the total weight of the meta-type wholly aromatic polyamide fiber and the para-type wholly aromatic polyamide fiber.

[0036] The blended yarn may further contain other synthetic fibers such as conductive fibers, etc. In this case, the conductive fibers are preferably fibers containing at least one of carbon black, conductive titanium oxide, conductive whiskers, and carbon nanotubes as a conductor in the conductive portion of the conductive fibers.

[0037] The form of the conductive fiber may be a structure in which the entire fiber is made of a conductive part, or the non-conductive part and the conductive part may have a cross-sectional shape such as a core-sheath, sandwich, or eccentric. The resin forming the conductive part and the non-conductive part is not particularly limited as long as it has fiber-forming properties. Specifically, examples of nylon resins include nylon 6, nylon 11, nylon 12, and nylon 66. Examples of polyester resins include polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycyclohexane terephthalate, and copolymers thereof, as well as those in which a part of the acid component (terephthalic acid) is replaced with isophthalic acid.

[0038] Examples of commercially available conductive fibers include "Metarian" (trade name) manufactured by Teijin Limited, "Megana" (trade name) manufactured by Unitika Fibers, "Luana" (trade name) manufactured by Toray Industries, Inc., and "Clacarbo" (trade name) manufactured by Kuraray Co., Ltd. In particular, core-sheath type composite fibers in which a conductive component is disposed in the sheath portion are preferred. As such a core-sheath type composite fiber, "NO SHOCK (registered trademark)" manufactured by Solcia Corporation is preferred.

[0039] The yarn constituting the woven or knitted fabric of the present invention is preferably a spun yarn in which the above-mentioned fibers are blended. In this case, due to restrictions on basis weight and thickness, it is preferable to use spun yarns of British cotton count 40 to 80 alone or in combination. The spun yarn may be used as a single yarn or after twisting, but in the case of a two-ply yarn, it is preferable that the yarn is not thicker than the equivalent of count 20.

[0040] In addition, the woven or knitted fabric of the present invention is preferably made of the above-mentioned blended yarn, but it is preferable to use a blended yarn of 100% meta-type wholly aromatic polyamide having a count of 60 to 80, with the blended yarn accounting for up to 35% of the entire woven or knitted fabric, as a means of adjusting the basis weight.

[0041] In the woven or knitted fabric of the present invention, the basis weight is 100 to 200 g / m 2 It is important that the thickness is 100g / m 2 If the thickness is less than 200 g / m, sufficient burst strength, heat insulation and flame resistance as exemplified by ISO 9151 and ISO 6942 Method B may not be obtained. 2 If it exceeds this value, the heat dissipation properties, such as the thermal resistance and water vapor transmission resistance, may be impaired.

[0042] The woven or knitted fabric of the present invention has a g / cm 2 It is important that the thickness under load is 0.6 to 1.1 mm. If it is less than 0.6 mm, the heat shielding property may be impaired, and if it exceeds 1.1 mm, the heat dissipation property may be impaired. In order to achieve both heat shielding property and heat dissipation property, the air permeability should be 160 to 350 cm. 2 / cm 2 / sec (preferably 200-260 cm 3 / cm 2 ·sec).

[0043] The woven or knitted fabric of the present invention can be woven or knitted by a conventional method. Either a circular knit structure or a warp knit structure may be used. In the case of circular knitting, single knits such as plain stitch, pearl knitting, and rib knitting, and double knit warp knits such as smooth knitting are preferably used, such as denbi, double denbi, half, and reverse half. In particular, in order to increase thermal conductivity, knitted fabrics with as few air layers, i.e., gaps or unevenness as possible are more preferable. Knitted structures that do not include tucks in the structure are preferable. The gauge number is preferably 22G (gauge) or less due to restrictions on basis weight and thickness.

[0044] It is preferable to color such a fabric. In this case, the coloring method can be a known method. That is, the wholly aromatic polyamide fiber (aramid fiber) may be dyed either in its original form or with a carrier agent.

[0045] Since the woven or knitted fabric of the present invention has the above-mentioned configuration, it is excellent in terms of comfort such as flame retardancy, heat insulation, and heat dissipation. In this regard, it is preferable that the fabric satisfies all of the following in the flame resistance test specified in ISO 15025 Procedure A. a) No flame b) No flaming or molten falling objects c) No holes larger than 5 mm d) Residual light lasts for 2 seconds or less e) Afterflame lasts less than 2 seconds

[0046] In addition, in the heat resistance test specified in ISO 17493, it is preferable that all of the following be satisfied when exposed to 260 to 265° C. for 5 minutes. a) Does not melt b) No dripping c) No flame d) Shrinkage rate is less than 10%

[0047] In addition, in the flame exposure test specified in ISO 9151, HTI 24 It is preferable that the heat transfer time is 4 seconds or more. 2 In a radiant heat exposure test with a heat flux of RHTI 24It is preferable that the dimensional change before and after five washings as specified in ISO 5077 is 8% or less. It is also preferable that the burst strength as specified in ISO 13938-1 or ISO 13938-2 is 50 cm 2 If the pressure exceeds 100 kPa, the test piece is 7.3 cm 2 In the case of , it is preferable that the thermal resistance value exceeds 200 kPa. 2 It is preferable that the water vapor transmission resistance value specified in ISO 11092 is less than 7m 2 It is preferably less than Pa / W.

[0048] Next, the heat protective clothing of the present invention is a heat protective clothing made of the above-mentioned woven or knitted fabric.Specific examples include station wear, or work clothes, worn by firefighters under their fireproof clothing.Since the heat protective clothing uses the above-mentioned woven or knitted fabric, it has excellent comfort, such as flame retardancy, heat shielding, and heat dissipation. EXAMPLES

[0049] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. (1) Weight Measurement was performed according to JIS L 1096 A method. (2) Thickness 7g / cm 2 The measurements were carried out with a load of 100 mm. (3) Breathability Measured according to JIS L1096-1990 Air Permeability Method A (Fragile method). (4) Flame resistance test Measurements were performed according to ISO 15025 Procedure A. (5) Heat resistance test The heat resistance test was performed according to ISO 17493, with the specimen exposed to temperatures of 260 to 265°C for 5 minutes. (6) Flame exposure test Measured based on ISO9151. (7) Radiant heat exposure test 20kW / m based on ISO 6942 Method B 2 The measurements were performed at a heat flux of 1000 MPa. (8) Dimensional change after washing Measured before and after five washes according to ISO 5077. (9) Bursting strength Test piece 7.3cm according to ISO 13938-1 2 was measured. (10) Thermal resistance value Measured according to ISO 11092. (11) Water vapor permeation resistance Measured according to ISO 11092.

[0050] The following materials were used in the examples and comparative examples. (Meta-type fully aromatic polyamide dyed staple fiber) "Conex" (registered trademark) manufactured by Teijin Limited, average single fiber fineness 2.2 dtex, fiber length 51 mm (Meta-type fully aromatic polyamide short fibers) "Conex" (registered trademark) manufactured by Teijin Limited, average single fiber fineness 2.2 dtex, fiber length 51 mm (Para-type fully aromatic polyamide staple fiber) "Technora" (registered trademark), manufactured by Teijin Limited, average single fiber fineness 1.7 dtex, fiber length 51 mm (No. 40 dope dyed blended staple fiber) 95% meta-type wholly aromatic polyamide dope-dyed staple fibers and 5% para-type wholly aromatic polyamide staple fibers were ring-spun in a conventional manner to obtain single yarns of British cotton count 40. (No. 40 unbleached staple fiber) 100% meta-type wholly aromatic polyamide staple fibers were ring spun in the usual manner to obtain single yarns of British cotton count 40. (60th grade unbleached staple fiber) 100% meta-type wholly aromatic polyamide staple fibers were ring spun in the usual manner to obtain single yarns of British cotton count 60. (40-count double yarn dyed blended staple fiber) British cotton number 40 dope-dyed staple fibers were twisted in the S direction into two-ply yarn at 19.8T / 2,54cm, and steam-set at 100℃ for 30 minutes. (Circular knitting machine) Circular knitting machines with 20, 22, and 28 gauge and a 33-inch bobbin diameter were used. (Warp knitting machine) A 28 gauge, 2 bar tricot machine was used.

[0051] [Examples 1 to 3, Comparative Examples 1 to 7] The knitted fabrics were obtained with the knitting type, knitting structure, yarn usage, and gauge shown in Table 1. The evaluation results are shown in Table 1.

[0052] [Table 1] [Industrial Applicability]

[0053] INDUSTRIAL APPLICABILITY According to the present invention, there are provided woven or knitted fabrics and heat protective clothing which are excellent in terms of comfort, such as flame retardancy, heat shielding properties and heat dissipation properties, and the industrial value thereof is extremely great.

Claims

1. A woven or knitted fabric is made of a circular knitted fabric containing a spun yarn in which meta-type wholly aromatic polyamide fiber and para-type wholly aromatic polyamide fiber are blended, and has a basis weight of 100 to 163 g / m ２ , and 7 g / cm ２ The thickness under load is 0.6 to 1.1 mm, and the air permeability is 160 to 350 cm ３ / cm ２ / sec and satisfies all of the following requirements (1) to (8). (1) In the flame resistance test specified in ISO 15025 Procedure A, Satisfy all of the following: a) No flame b) No flaming or molten falling objects c) No holes larger than 5 mm d) Residual light lasts for 2 seconds or less e) Afterflame lasts less than 2 seconds (2) In the heat resistance test specified in ISO 17493, the material satisfies all of the following requirements when exposed to 260-265°C for 5 minutes. a) Does not melt b) No dripping c) No flame d) Shrinkage rate is less than 10% (3) In the flame exposure test specified in ISO 9151, HTI24 is 4 seconds or more. (4) According to the heat flux of 20 kW / m 2 specified in ISO 6942 METHOD B In a radiant heat exposure test, RHTI24 is 7 seconds or more. (5) The dimensional change after five washes as specified in ISO 5077 is 8% or less. (6) The bursting strength as specified in ISO 13938-1 or ISO 13938-2 exceeds 100 kPa for a 50 cm 2 test piece, and exceeds 200 kPa for a 7.3 cm 2 test piece. (7) The thermal resistance value as defined in ISO 11092 is less than 0.055 m 2 K / W. (8) The water vapor transmission resistance value as defined in ISO 11092 is less than 7 m 2 Pa / W.

2. A thermal protective garment comprising the woven or knitted fabric described in claim 1.

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