Flame-retardant fabrics and work clothes using them

Abstract

This invention provides a flame-retardant fabric containing acrylic fibers and cellulose fibers. The cellulose fibers are selected from one or more types of regenerated cellulose fibers and natural cellulose fibers. The flame-retardant fabric contains 65-90% by weight of acrylic fibers and 10-35% by weight of cellulose fibers relative to the total weight of the fabric. The acrylic fibers contain magnesium compounds within the fibers, and the flame-retardant fabric contains 2.5-4.5% by weight of magnesium compounds. The afterflame time and afterglow time, as determined by a flammability test based on ISO 15025:2000, are both less than 2 seconds.

Description

Technical Field

[0001] This invention relates to flame-retardant fabrics and work clothes using the same. Background Technology

[0002] Firefighters and workers exposed to fire hazards in environments such as oil, petrochemical, coal mines, power plants, welding, and metal processing sites require flame-retardant work clothes. Various fabric compositions have been proposed as flame-retardant work clothes fabrics. For example, Patent Document 1 discloses a flame-retardant fabric containing 40–56% by weight of flame-retardant modified polyacrylonitrile fiber using antimony compounds as flame retardants, 5–25% by weight of natural cellulose fibers, and 20–40% by weight of flame-retardant viscose fiber.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: International Publication No. 2010 / 010369 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] However, in recent years, there have been concerns about the environmental impact of the leaching or emission of flame retardants, namely antimony compounds, and efforts have been made to improve them. Furthermore, from the perspective of ensuring excellent flame retardancy while allowing for repeated use as workwear, there are also efforts to improve quality, style, and washability. In addition, there is room for improvement from a cost perspective.

[0008] In order to solve the above-mentioned problems, the present invention provides a flame-retardant fabric and work clothes made thereto, which does not have concerns about environmental impact, has high flame retardancy, and thus has excellent washability and quality.

[0009] Methods for solving problems

[0010] One or more embodiments of the present invention relate to a flame-retardant fabric containing acrylic fibers and cellulose fibers, wherein the cellulose fibers are selected from one or more types of regenerated cellulose fibers and natural cellulose fibers, and the flame-retardant fabric contains, relative to the total weight of the fabric, 65-90% by weight of the acrylic fibers and 10-35% by weight of the cellulose fibers, wherein the acrylic fibers contain magnesium compounds within the fibers, and the flame-retardant fabric contains, relative to the total weight of the fabric, 2.5-4.5% by weight of magnesium compounds, and the flame-retardant fabric, as determined by a flammability test based on ISO 15025:2000, has an afterflame time of less than 2 seconds and an afterglow time of less than 2 seconds.

[0011] One or more embodiments of the present invention relate to workwear using the aforementioned flame-retardant fabric.

[0012] Invention Effects

[0013] According to the present invention, it is possible to provide flame-retardant fabrics and work clothes using the same, which reduce concerns about environmental impact, have good flame retardancy, washability, and quality style. Detailed Implementation

[0014] The inventors of this invention have achieved excellent flame retardancy while reducing environmental concerns by incorporating a specified amount of acrylic and cellulose fibers into fabrics containing a specified amount of magnesium compounds. This results in shorter afterflame and afterglow times in flaming tests, and remarkably, good wash durability and quality characteristics. In one or more embodiments of this invention, "afterflame time" and "afterglow time" can be measured separately using a flammability test based on ISO 15025:2000. In one or more embodiments of this invention, wash durability refers to good flame retardancy after washing. When flame retardants are applied to the surface of fibers and fabric, they tend to detach during washing, resulting in poor wash durability. However, in the flame-retardant fabrics of one or more embodiments of this invention, good wash durability is achieved by using acrylic fibers containing magnesium compounds within the fibers.

[0015] The flame-retardant fabrics of one or more embodiments of the present invention contain magnesium compounds but are substantially free of antimony compounds, thus reducing concerns about environmental impact and lowering costs. In this specification, "substantially free of antimony compounds" means that antimony compounds are not intentionally added to the fibers or fabrics as flame retardants.

[0016] In this specification, when “~” is used to represent a numerical range, the numerical range includes the two endpoints (upper limit and lower limit) stated before and after the “~”. For example, a numerical range called “A~B” is a range that includes the two endpoints A and B. Furthermore, in this specification, when a numerical range is stated multiple times, it includes a numerical range formed by appropriately combining the upper and lower limits of different numerical ranges.

[0017] <Magnesium compounds>

[0018] In one or more embodiments of the present invention, by containing magnesium compounds as flame retardants in the fabric, a carbonized layer is easily formed during combustion, thereby improving flame retardancy and washability.

[0019] In the flame-retardant fabrics of one or more embodiments of the present invention, the ratio of magnesium compounds relative to the total weight of the fabric is 2.5 to 4.5 wt%, preferably 2.6 to 4.5 wt%, 2.7 to 4.5 wt%, 2.8 to 4.5 wt%, 2.9 to 4.5 wt%, 3.0 to 4.5 wt%, 3.1 to 4.5 wt%, 3.2 to 4.5 wt%, 3.3 to 4.5 wt%, 3.4 to 4.4 wt%, 3.5 to 4.4 wt%, 3.6 to 4.4 wt%, 3.7 to 4.4 wt%, 3.8 to 4.3 wt%, or 3.9 to 4.3 wt%. When the ratio of magnesium compounds is less than 2.5 wt%, sufficient flame retardancy is not obtained; when it is greater than 4.5 wt%, although higher flame retardancy can be obtained, the quality, feel, fiber strength, and fabric strength are compromised.

[0020] In one or more embodiments of the present invention, the average particle size of the magnesium compound is preferably 0.3 μm or more, more preferably 0.3 to 2.0 μm, and even more preferably 0.5 to 1.5 μm. If the average particle size is 0.3 μm or more, the surface area of ​​the magnesium compound particles will not be excessively increased, and static electricity can be suppressed in fiber processing steps such as spinning, making processing easier. If the average particle size is 2.0 μm or less, clogging of the spinning spinneret will not occur in the spinning process, which is preferred in manufacturing. In this specification, the average particle size of the magnesium compound can be measured, for example, by laser diffraction when it is a powder, and by laser diffraction or dynamic light scattering when it is a dispersion (dispersion liquid) dispersed in water or an organic solvent. The average particle size of the magnesium compound in the fiber can be determined, for example, by measuring the particle size of 100 magnesium compound particles in the fiber using a microscope and calculating the arithmetic mean diameter.

[0021] In one or more embodiments of the present invention, a magnesium compound is contained within the acrylic fiber. In the acrylic fiber, the magnesium compound preferably contains 2.8 to 6.9% by weight, more preferably 3.0 to 6.7% by weight, even more preferably 3.2 to 6.5% by weight, and most preferably 3.5 to 6.0% by weight, relative to the total weight of the fiber. When the content of the magnesium compound is less than 2.8% by weight, there is concern about insufficient flame retardancy. On the other hand, if the content of the magnesium compound exceeds 6.9% by weight, there are concerns about increased insulation resistance during fiber spinning and other processing, easy generation of static electricity, entanglement-like defects during carding processes, and difficulties in processing.

[0022] In one or more embodiments of the present invention, examples of magnesium compounds include magnesium oxide, magnesium peroxide, magnesium hydroxide, magnesium fluoride, magnesium chloride, magnesium bromide, magnesium iodide, magnesium hydride, magnesium diboride, magnesium nitride, magnesium sulfide, magnesium carbonate, calcium magnesium carbonate, magnesium nitrate, magnesium sulfate, magnesium sulfite, magnesium perchlorate, trimagnesium phosphate, magnesium permanganate, and magnesium phosphate. From the viewpoint of ease of operation, magnesium oxide and magnesium hydroxide are suitable for use. Furthermore, from the viewpoint of Mohs hardness, magnesium hydroxide is suitable for use.

[0023] In one or more embodiments of the present invention, the preferred Mohs hardness of the magnesium compound is less than 5, more preferably less than 4. Mohs hardness is an indicator of the hardness of a mineral. For example, a Mohs hardness of 5 refers to a degree of hardness where a blade can easily, but not severely, inflict a scratch, while a Mohs hardness of 6 refers to a degree of hardness where a blade is difficult to scratch and will damage the blade. Magnesium hydroxide and magnesium oxide can ensure flame retardancy equivalent to conventional flame retardants, namely antimony compounds. Furthermore, in fibers containing this magnesium compound, magnesium hydroxide is more stable for spinning compared to magnesium oxide. Although this is only a conjecture, the Mohs hardness of magnesium hydroxide is approximately 3, and that of magnesium oxide is approximately 7. Since magnesium hydroxide is softer than magnesium oxide, the abrasion of the cutter when cutting acrylic fibers containing magnesium hydroxide and woven fabrics containing such acrylic fibers is reduced, which presumably reduces the abrasion of the machinery used for spinning. Additionally, the minimum Mohs hardness is 1.

[0024] In one or more embodiments of the present invention, the magnesium hydroxide compound is not particularly limited, and examples include powder obtained by crushing natural brucite, powder obtained by neutralizing an aqueous solution of magnesium salt with alkali, powder obtained by treating magnesium hydroxide particles with phosphates, borates, etc., and magnesium hydroxide compounds obtained by a method of slowly generating magnesium hydroxide by hydrating magnesium oxide. Alternatively, magnesium hydroxide compounds with a coating can be obtained by adsorption with a substance that can be adsorbed around the magnesium hydroxide compound particles, or by surface treatment. Among these, magnesium hydroxide with a coating obtained by surface treatment with a silane coupling agent is preferred from the viewpoint of suppressing static electricity. While the reason for improving static electricity suppression by surface treatment with a silane coupling agent is only a conjecture, it is believed that: by performing silane coupling treatment on the surface of magnesium hydroxide particles, the dispersibility of acrylic fibers with silane-coupled magnesium hydroxide is improved, resulting in the suppression of static electricity. Furthermore, if an oiling process is performed on the fiber surface for the purpose of improving processability, the effect of the oiling agent can be fully obtained on the surface of the magnesium hydroxide particles, and processability can be significantly improved. As for the type of silane coupling agent, there is no particular limitation as long as it can improve the compatibility with the acrylonitrile copolymers described later, and there are no particular limitations on whether it is cross-linked or non-cross-linked.

[0025] <Acrylic Fibers>

[0026] In one or more embodiments of the present invention, from the viewpoint of flame retardancy, the acrylic fiber is preferably composed of an acrylonitrile copolymer obtained by copolymerizing 30-85% by weight of acrylonitrile and 15-65% by weight of other components. As other components, from the viewpoint of flame retardancy, for example, one or more halogenated monomers selected from halogenated vinyl monomers and halogenated vinylidene monomers are preferably used. The acrylonitrile content in the aforementioned acrylonitrile copolymer is more preferably 40-75% by weight. The content of the halogenated vinyl monomers and / or halogenated vinylidene monomers in the aforementioned acrylonitrile copolymer is more preferably 25-60% by weight. The aforementioned acrylonitrile copolymer may further contain monomers containing sulfonic acid groups as other components. The content of the monomers containing sulfonic acid groups in the aforementioned acrylonitrile copolymer is preferably 0-3% by weight.

[0027] Examples of halogenated monomers include halogenated vinyl monomers and halogenated vinylidene monomers. Examples of halogenated vinyl monomers include vinyl chloride and vinyl bromide, and examples of halogenated vinylidene monomers include vinylidene chloride and vinylidene bromide. One or more of these halogenated monomers can be used. Vinyl chloride monomers are preferred over vinylidene chloride monomers. When vinyl chloride monomers are used, by selecting magnesium compounds as flame retardants and compounding them in a specific amount, a char layer is easily formed during combustion, achieving high flame retardancy. The mechanism is not entirely clear, but it is speculated that in the presence of vinyl chloride, magnesium compounds function as intumescent flame retardants, easily forming a char layer, i.e., expansion, during combustion. Furthermore, when using vinylidene chloride, if magnesium compounds are selected as flame retardants, the acrylonitrile copolymer is colored, limiting its use in clothing applications. However, when using vinyl chloride, the acrylonitrile copolymer is not colored, making it preferable.

[0028] There are no particular limitations on the monomers containing sulfonic acid groups mentioned above. For example, unsaturated carboxylic acids represented by acrylic acid and methacrylic acid and their salts, methacrylates represented by methyl methacrylate, esters of unsaturated carboxylic acids represented by glycidyl methacrylate, vinyl esters represented by vinyl acetate and vinyl butyrate, and monomers containing sulfonic acid can be used. There are also no particular limitations on the monomers containing sulfonic acid mentioned above. Allyl sulfonic acid, methyl allyl sulfonic acid, styrene sulfonic acid, isoprene sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid, and their sodium salts and other metal salts and amine salts can be used. These monomers containing other copolymerizable sulfonic acid groups can be used alone or in combination of two or more. Monomers containing sulfonic acid groups can be used as needed, but if the content of monomers containing sulfonic acid groups in the above acrylonitrile copolymer is 0-3% by weight, the production stability of the spinning process is excellent.

[0029] In one or more embodiments of the present invention, from the viewpoint of improving the flame retardancy and spinning processability of acrylic fibers, the acrylonitrile copolymer preferably contains 30-85% by weight of acrylonitrile, 15-65% by weight of halogenated monomers and 0-3% by weight of monomers containing sulfonic acid groups; more preferably, it contains 35-80% by weight of acrylonitrile, 20-65% by weight of halogenated monomers and 0-3% by weight of monomers containing sulfonic acid groups; even more preferably, it contains 40-75% by weight of acrylonitrile, 25-60% by weight of halogenated monomers and 0-3% by weight of monomers containing sulfonic acid groups; and particularly preferably, it contains 40-70% by weight of acrylonitrile, 30-60% by weight of halogenated monomers and 0-3% by weight of monomers containing sulfonic acid groups.

[0030] In one or more embodiments of the present invention, from the viewpoint of improving not only the flame retardancy and spinning processability of acrylic fibers, but also the brightness, the acrylonitrile copolymer preferably contains acrylonitrile: 30-85% by weight, vinyl chloride: 15-65% by weight, and monomers containing sulfonic acid groups: 0-3% by weight; more preferably, it contains acrylonitrile: 35-80% by weight, vinyl chloride: 20-65% by weight, and monomers containing sulfonic acid groups: 0-3% by weight; even more preferably, it contains acrylonitrile: 40-75% by weight, vinyl chloride: 25-60% by weight, and monomers containing sulfonic acid groups: 0-3% by weight; particularly preferably, it contains acrylonitrile: 40-70% by weight, vinyl chloride: 30-60% by weight, and monomers containing sulfonic acid groups: 0-3% by weight.

[0031] In one or more embodiments of the present invention, the acrylic fibers contain the aforementioned acrylonitrile copolymer and magnesium compounds to improve the flame retardancy of the flame-retardant fabric. Carbonization during combustion creates an oxygen-deficient environment inside the flame-retardant fabric, which also helps prevent flame penetration onto the surface. Furthermore, because the acrylic fibers contain magnesium compounds within the fibers, the fabrics containing these acrylic fibers exhibit good wash durability, i.e., good flame retardancy after washing.

[0032] In one or more embodiments of the present invention, by using acrylic fibers containing magnesium compounds, the generation of harmful gases, namely carbon monoxide, during combustion can be suppressed compared with the use of antimony compounds. This allows for the production of flame-retardant fabrics with excellent flame retardancy and low coloring (high brightness) while suppressing environmental impact.

[0033] In one or more embodiments of the present invention, for example from the viewpoint of durability, the acrylic fiber preferably has a single fiber strength of 1.0 to 4.0 cN / dtex, more preferably 1.5 to 3.5 cN / dtex. For example from the viewpoint of practicality, the acrylic fiber preferably has an elongation of 15 to 40%, more preferably 20 to 30%. The single fiber strength and elongation can be measured according to JIS L 1015:2010.

[0034] In one or more embodiments of the present invention, the acrylic fiber is a solution-dyed fiber. Solution dyeing refers to coloring a chemical fiber by adding dyeing materials such as pigments or dyes to the raw materials (spinning solution, polymer-containing solution, polymer) of the chemical fiber. This acrylic fiber is capable of solution dyeing. Through solution dyeing, the desired color can be easily obtained without adding new manufacturing processes, and fibers that are less prone to color migration and fading during washing can be obtained.

[0035] In one or more embodiments of the present invention, the acrylic fibers may also contain, as needed, other flame retardants besides magnesium compounds that do not pose environmental risks due to leaching or emission. Furthermore, other additives may be included, as needed, such as antistatic agents, heat-resistant agents, lightfastness improvers, whiteness improvers, devitrification preventers, and colorants. Additionally, there are no particular limitations on the coating method; it can be spray coating or coating after cutting.

[0036] In one or more embodiments of the present invention, the method for manufacturing acrylic fibers is not particularly limited, and they can be manufactured by heat treatment after spinning a composition containing an acrylonitrile copolymer (preferably an acrylonitrile copolymer containing acrylonitrile and vinyl chloride) and a magnesium compound. Specific manufacturing methods include known methods such as wet spinning, dry spinning, and semi-dry / semi-wet spinning. For example, when using wet spinning, except for using a spinning solution obtained by dissolving the aforementioned acrylonitrile copolymer in an organic solvent and adding a magnesium compound, similar to using general acrylic fibers, the spinning solution can be extruded into a coagulation bath through a nozzle and coagulated, followed by stretching, washing, drying, heat treatment, and, if necessary, crimping, and then cutting. Stretching can be performed simultaneously with or before washing, or before or after drying. Furthermore, an oiling agent can be applied to the fibers as needed before crimping or before drying. Examples of organic solvents mentioned above include dimethylformamide, dimethylacetamide, acetone, and dimethyl sulfoxide, but inorganic solvents such as aqueous solutions of thiocyanate and nitric acid can also be used.

[0037] Cellulose-based fibers

[0038] In one or more embodiments of the flame-retardant fabric of the present invention, for the purpose of providing excellent quality or wash durability, the fabric contains 10 to 35% by weight of cellulose-based fibers, more preferably 15 to 30% by weight, and even more preferably 20 to 30% by weight, relative to the total weight of the fabric. The aforementioned cellulose-based fibers can be at least one selected from natural cellulose-based fibers and regenerated cellulose-based fibers. Furthermore, these fibers can be used alone or in combination of two or more.

[0039] Examples of natural cellulose fibers include cotton fiber, kapok fiber, flax fiber, hemp fiber, ramie fiber, jute fiber, Manila hemp fiber, kenaf fiber, and other natural cellulose fibers.

[0040] Examples of regenerated cellulose fibers include rayon fibers, flame-retardant rayon fibers, lyocell fibers, and flame-retardant lyocell fibers.

[0041] The aforementioned rayon fiber can be obtained by reacting alkali and carbon disulfide in cellulose raw materials to generate cellulose xanthate, dissolving the cellulose xanthate in caustic soda, and then performing wet spinning.

[0042] The above-mentioned lyocell fiber does not require a process of modifying the cellulose raw material. It can be obtained by dissolving the cellulose raw material in N-methylmorpholine N-oxide and then performing dry and wet spinning.

[0043] The aforementioned flame-retardant rayon fiber is preferably a rayon fiber containing a phosphorus-based flame retardant. The phosphorus-based flame retardant is not particularly limited, and examples include phosphate ester compounds, halophosphate ester compounds, condensed phosphate ester compounds, polyphosphate compounds, and polyphosphate ester compounds. While the aforementioned flame-retardant rayon fiber containing a phosphorus-based flame retardant is not particularly limited, from the viewpoint of improving flame retardancy, it is preferable to contain at least 0.5% by weight of phosphorus derived from the aforementioned phosphorus-based flame retardant relative to the total weight of the fiber, more preferably at least 0.8% by weight. On the other hand, from the viewpoint of fiber strength, the aforementioned flame-retardant rayon fiber containing a phosphorus-based flame retardant preferably contains at least 10% by weight of phosphorus derived from the aforementioned phosphorus-based flame retardant relative to the total weight of the fiber. Commercially available flame-retardant rayon fibers, such as Lenzing FR (flame-retardant lyocell) manufactured by Lenzing Corporation and JWELL FR (flame-retardant rayon) manufactured by Jilin Chemical Fiber Co., Ltd., can also be used as the aforementioned flame-retardant rayon fiber containing a phosphorus-based flame retardant. The phosphorus content can be determined by fluorescence X-ray analysis.

[0044] The aforementioned flame-retardant lyocell fiber is preferably a lyocell fiber containing a phosphorus-based flame retardant. The aforementioned phosphorus-based flame retardant is not particularly limited, and examples include phosphate ester compounds, halophosphate ester compounds, condensed phosphate ester compounds, polyphosphate compounds, and polyphosphate ester compounds.

[0045] Flame-retardant fabrics

[0046] In one or more embodiments of the present invention, the flame-retardant fabric contains 65 to 90% by weight of the aforementioned acrylic fibers relative to the total weight of the fabric. When the content of acrylic fibers is less than 65% by weight, the flame retardancy is poor; if it exceeds 90% by weight, the quality and style of the fabric are poor due to the insufficient content of cellulose fibers.

[0047] In one or more embodiments of the present invention, from the viewpoint of balancing flame retardancy and quality, the flame-retardant fabric preferably contains 70-90% by weight of the above-mentioned acrylic fibers and 10-30% by weight of the above-mentioned natural cellulose fibers, and more preferably contains 80-90% by weight of the above-mentioned acrylic fibers and 10-20% by weight of the above-mentioned natural cellulose fibers.

[0048] As another embodiment of the present invention, the flame-retardant fabric may also contain the above-mentioned acrylic fibers: 65-90% by weight and the above-mentioned rayon fibers: 10-35% by weight, and particularly preferably contains the above-mentioned acrylic fibers: 65-85% by weight and the above-mentioned rayon fibers: 15-35% by weight.

[0049] As another embodiment of the present invention, the flame-retardant fabric may also contain the above-mentioned acrylic fibers: 65-90% by weight and the above-mentioned lyocell fibers: 10-35% by weight, and particularly preferably contains the above-mentioned acrylic fibers: 65-85% by weight and the above-mentioned lyocell fibers: 15-35% by weight.

[0050] As another embodiment of the present invention, the flame-retardant fabric may also contain the above-mentioned acrylic fibers: 65-90% by weight and the above-mentioned flame-retardant rayon fibers: 10-35% by weight, and particularly preferably contains the above-mentioned acrylic fibers: 70-80% by weight and the above-mentioned flame-retardant rayon fibers: 20-30% by weight.

[0051] As another embodiment of the present invention, the flame-retardant fabric may also contain the above-mentioned acrylic fibers: 65-90% by weight and the above-mentioned flame-retardant lyocell fibers: 10-35% by weight, and particularly preferably contains the above-mentioned acrylic fibers: 65-85% by weight and the above-mentioned flame-retardant lyocell fibers: 15-35% by weight.

[0052] As another embodiment of the present invention, the flame-retardant fabric may also contain two or more cellulose fibers selected from rayon fibers, flame-retardant rayon fibers, lyocell fibers and flame-retardant lyocell fibers.

[0053] In the flame-retardant fabrics of one or more embodiments of the present invention, natural cellulose fibers and regenerated cellulose fibers can be used alone or in combination. When used in combination, the preferred weight ratio is natural cellulose fibers: regenerated cellulose fibers = 1:2 to 3:1.

[0054] In one or more embodiments of the present invention, the flame-retardant fabric may contain other fibers besides acrylic fibers and cellulose fibers, without hindering the purpose and effect of the present invention. Examples of other fibers include conductive fibers, heat-resistant fibers, and high-strength, high-elasticity fibers. For example, conductive fibers may include metal fibers, metal-plated fibers, copper compound-coated fibers, and fibers with conductive additives; heat-resistant fibers may include meta-aromatic polyamide fibers, polyoxadiazole fibers, polyimide fibers, and polyamide-imide fibers; and high-strength, high-elasticity fibers may include nylon fibers, polyester fibers, para-aromatic polyamide fibers, and polyaromatic fibers. In the above-mentioned flame-retardant fabric, the other fibers may contain 10% or less by weight, 8% or less by weight, or 1% or less by weight in the total fabric.

[0055] In the flame-retardant fabrics of one or more embodiments of the present invention, from the viewpoint of strength, the aforementioned acrylic fibers, cellulose fibers, and other fibers can be either short or long fibers, and can be appropriately selected according to the method of use. The fineness of a single fiber can be appropriately selected according to the intended use of the workwear, but is preferably 1 to 50 dtex, more preferably 1.5 to 30 dtex, and even more preferably 1.7 to 15 dtex. The cut length can be appropriately selected according to the intended use of the workwear. For example, examples include sheared fibers (e.g., fiber length 0.1 to 5 mm), short fibers (e.g., fiber length 38 to 128 mm), or completely uncut long fibers (filaments).

[0056] The flame-retardant fabrics of one or more embodiments of the present invention are not particularly limited, but from the viewpoint of quality, a weight per unit area of ​​200 to 400 g / m² is preferred. 2 More preferably, it is 220–380 g / m 2 More preferably 250–350 g / m 2 .

[0057] There are no particular limitations on the form of the flame-retardant fabric; examples include woven fabrics and knitted fabrics. There are no particular limitations on the weave of the aforementioned woven fabrics; for example, it can be a plain weave, twill weave, satin weave, or other three-part weaves, or a variable weave using special looms such as multi-arm looms or jacquard looms. Furthermore, there are no particular limitations on the weave of the aforementioned knitted fabrics; it can be any of circular knit, weft knit, or warp knit. From the viewpoint of excellent durability, the aforementioned flame-retardant fabric is preferably a woven fabric, and more preferably a twill weave fabric.

[0058] In one or more embodiments of the present invention, the flame-retardant fabric exhibits excellent flame retardancy, with an afterflame time of 2 seconds or less and an afterglow time of 2 seconds or less, as determined by a flammability test based on ISO 15025:2000; preferably, the afterflame time is 0 seconds and the afterglow time is 0 seconds. In one or more preferred embodiments of the present invention, from the viewpoint of excellent flame retardancy, the aforementioned flame-retardant fabric preferably has a limiting oxygen index of 27 or more, more preferably 28 or more, 29 or more, 30 or more, 31 or more, 32 or more, 33 or more, 34 or more, 35 or more, or 36 or more, as determined by JIS L 1091E method (E-1):1999. In one or more preferred embodiments of the present invention, wash durability can also be confirmed, for example, by measuring the limiting oxygen index of flame-retardant fabric washed according to the washing method based on ISO 6330:2012, as determined by JIS L 1091:1999. The limiting oxygen index of flame-retardant fabric washed 30 times according to the washing method based on ISO 6330:2012, as determined by JIS L 1091E method (E-1):1999, is preferably 27 or more, 28 or more, 29 or more, 30 or more, 31 or more, 32 or more, 33 or more, 34 or more, 35 or more, or 36 or more.

[0059] <Work clothes>

[0060] In one or more embodiments of the present invention, the aforementioned flame-retardant fabric is suitable for use as workwear fabric requiring flame retardancy. In one or more embodiments of the present invention, the workwear can be made using the aforementioned flame-retardant fabric and a known sewing method. In one or more embodiments of the present invention, the aforementioned flame-retardant fabric, due to its excellent flame retardancy and wash durability, also gives the workwear excellent flame retardancy and wash durability. Furthermore, even after repeated washing of the aforementioned flame-retardant fabric, it maintains excellent quality and style; therefore, the aforementioned workwear can maintain its flame retardancy and quality and style even after repeated washing. In one or more embodiments of the present invention, the aforementioned workwear is suitable for use as workwear for all types of work requiring flame retardancy. For example, although not particularly limited, it can be used as protective clothing (firefighting suit) worn by firefighters, as protective clothing worn in work sites prone to fire such as oil, petrochemical, coal mines, power plants, and welding, and as workwear worn in work sites where dust explosions are anticipated, such as metal processing.

[0061] Example

[0062] The present invention will now be described in detail through examples. However, the present invention is not limited to these examples.

[0063] The following fibers were used in the examples and comparative examples.

[0064] <fiber>

[0065] Acrylic Fiber I: This acrylic fiber contains 100 parts by weight of an acrylonitrile copolymer formed from 49.5 wt% acrylonitrile, 49.5 wt% vinyl chloride, and 1.0 wt% sodium styrene sulfonate, and 5 parts by weight of magnesium compound. It also contains 4.8 wt% magnesium hydroxide (manufactured by Kyowa Chemical Industry Co., Ltd., trade name "Kisma5", average particle size 2 μm, Mohs hardness 3) relative to the total fiber weight. The single fiber fineness is 1.7 dtex, and the fiber length is 51 mm.

[0066] Acrylic Fiber II: An acrylic fiber containing 100 parts by weight of an acrylonitrile copolymer formed from 49.5 wt% acrylonitrile, 49.5 wt% vinylidene chloride, and 1.0 wt% sodium styrene sulfonate, and 9.5 parts by weight of antimony pentoxide, containing 8.7 wt% antimony pentoxide relative to the total fiber weight. The single fiber fineness is 1.7 dtex, and the fiber length is 51 mm.

[0067] Flame-retardant Lyocell fiber: "Lenzing FR (registered trademark)" manufactured by Lenzing, containing phosphorus-based flame retardants, with a single fiber fineness of 2.2 dtex and a fiber length of 51 mm.

[0068] Lyocell fiber: "Tencel (registered trademark)" manufactured by Lenzing, with a single fiber fineness of 1.3 dtex and a fiber length of 51 mm.

[0069] Natural cellulose fibers: cotton fibers with a cut length of less than 31mm

[0070] Meta-aromatic polyamide fiber: "Newstar" (registered trademark) manufactured by Yantai Tayho Advanced Materials Co., Ltd., with a fineness of 1.7 dtex and a fiber length of 51 mm.

[0071] (Examples 1-7, Comparative Examples 1-2, Reference Example 1)

[0072] Using the fiber blending ratios shown in Table 1 below, short fiber yarns with the counts shown in Table 1 are manufactured by conventional ring spinning. Using these short fiber yarns, knitted fabrics with plain knit weave structures having the unit area weights shown in Table 1 are produced.

[0073] (Comparative Example 3)

[0074] Using 100% by weight of natural cellulose fibers, staple yarns with the counts shown in Table 1 below are manufactured through conventional ring spinning. Using these staple yarns, plain knit fabrics with the area weights shown in Table 1 below are produced. The resulting fabrics are then subjected to the following processing.

[0075] A phosphorus-based compound was used for flame retardant treatment via Pyrovatex processing. First, a flame retardant treatment solution (processing agent) was prepared containing 400 g / L of a phosphorus-based compound (trade name "Pyrovatex CP NEW", manufactured by Huntsmans, N-hydroxymethyldimethylphosphopropionic acid amide), 60 g / L of a crosslinking agent (trade name "Bekkamin J-101", manufactured by DIC, hexamethoxyhydroxymethyl melamine), 30 g / L of a softener (trade name "ULTRATEX FSA NEW", manufactured by Huntsmans, silicone-based softener), 20.7 g / L of 85% phosphoric acid, and 5 ml / L of a penetrating agent (trade name "Inbajin PBN", manufactured by Huntsmans). After the flame-retardant treatment liquid was fully impregnated into the woven fabric, it was rolled in using a dewatering machine at a roll-in rate of 80±2%. Then, it was pre-dried at 110°C for 5 minutes and heat-treated at 150°C for 5 minutes. Next, the woven fabric was washed with a sodium carbonate aqueous solution and water, neutralized with hydrogen peroxide water, and after washing and dehydration, dried in a rotary dryer at 60°C for 30 minutes to obtain the flame-retardant woven fabric.

[0076] The flame retardancy, quality style, and wash durability of the woven fabrics obtained according to the examples and comparative examples were evaluated below. The results are shown in Table 2 below.

[0077] (Flame retardancy evaluation 1)

[0078] Flammability tests were conducted based on ISO 15025:2000A, measuring afterflame time and afterglow time. The acceptable criteria for flame retardancy were that the flame did not reach either the top or left or right end of the test piece, the afterflame time and afterglow time were both less than 2 seconds, and there were no openings in the fabric. When these criteria were met, the flame retardancy was considered good.

[0079] (Flame retardancy evaluation 2)

[0080] The limiting oxygen index (LOI) of the woven fabric was determined according to the method based on JIS L 1091E (E-1): 1999. A LOI value of 27 or higher is considered to indicate good flame retardancy.

[0081] (Washability)

[0082] The fabric was washed 30 times according to ISO 6330:2012, and the limiting oxygen index (LOI) of the washed fabric was determined according to JIS L 1091E (E-1):1999. A wash durability of 27 or higher after 30 washes was considered good.

[0083] (Quality Style)

[0084] The softness of the knitted fabric is evaluated by a professional sensory evaluator, and the quality style is determined according to the following criteria.

[0085] Good: The fabric is soft.

[0086] Defect: Stiff fabric

[0087] Table 1

[0088]

[0089] Table 2

[0090]

[0091] The results in Table 2 above clearly show that the woven fabrics of the embodiments exhibit excellent flame retardancy and good quality. The woven fabrics of the embodiments using acrylic fibers containing magnesium compounds as flame retardants, like the woven fabrics of Reference Example 1 using acrylic fibers containing antimony compounds as flame retardants, also demonstrate good flame retardancy. Furthermore, in the woven fabrics of the embodiments, because the magnesium compounds are contained within the acrylic fibers, the LOI value after 30 washes remains the same as before washing, indicating good wash durability, i.e., good flame retardancy after washing.

[0092] On the other hand, the woven fabric of Comparative Example 1, which does not contain cellulose fibers, developed holes in the flammability test based on ISO 15025:2000A, and its flame retardancy (more specifically, flame shielding) was poor.

[0093] The woven fabric of Comparative Example 2, which has a lower content of acrylic fibers and magnesium compounds, exhibited a flame time of 54 seconds in the flammability test based on ISO 15025:2000A, indicating poor flame retardancy (more specifically, flame shielding). Furthermore, its limiting oxygen index (LOI), determined using JIS L 1091E (E-1):1999, was only 24, also indicating poor flame retardancy.

[0094] The woven fabric of Comparative Example 3, which does not contain acrylic fibers or magnesium compounds, has good flame retardancy due to the presence of a phosphorus-based flame retardant. However, the quality is poor because the phosphorus-based compounds adhere to the fabric (fiber). Furthermore, because the phosphorus-based compounds adhere to the fibers and are not contained within them, the LOI value after 30 washes is significantly lower than before washing, resulting in poor wash durability, i.e., poor flame retardancy after washing.

[0095] The present invention is not particularly limited, but is suitable to include the following embodiments.

[0096] [1] A flame-retardant fabric, comprising acrylic fibers and cellulose fibers, wherein,

[0097] The cellulose-based fiber is selected from one or more types of regenerated cellulose-based fibers and natural cellulose-based fibers.

[0098] The flame-retardant fabric contains, relative to the total weight of the fabric, 65-90% by weight of the acrylic fibers and 10-35% by weight of the cellulose fibers.

[0099] The acrylic fiber contains magnesium compounds inside the fiber.

[0100] The flame-retardant fabric contains 2.5 to 4.5% by weight of magnesium compounds relative to the total weight of the fabric.

[0101] The flame-retardant fabric, as determined by the flammability test based on ISO 15025:2000, has an afterflame time of less than 2 seconds and an afterglow time of less than 2 seconds.

[0102] [2] According to the flame-retardant fabric described in [1] above, wherein the acrylic fiber comprises an acrylonitrile copolymer, the acrylonitrile copolymer comprising acrylonitrile: 30-85% by weight, one or more halogenated monomers selected from halogenated vinyl monomers and halogenated vinylidene monomers: 15-65% by weight, and sulfonated vinyl monomers: 0-3% by weight.

[0103] [3] According to the flame-retardant fabric described in [1] or [2] above, wherein the acrylic fiber contains 2.8 to 6.9% by weight of magnesium compound inside the fiber.

[0104] [4] The flame-retardant fabric according to any one of [1] to [3] above, wherein the regenerated cellulose fiber is selected from one or more of rayon fiber, flame-retardant rayon fiber, lyocell fiber and flame-retardant lyocell fiber.

[0105] [5] The flame-retardant fabric according to any one of [1] to [4] above, wherein the flame-retardant fabric contains, relative to the total weight of the fabric, 65 to 90% by weight of the acrylic fibers and 10 to 35% by weight of the regenerated cellulose fibers.

[0106] [6] The flame-retardant fabric according to any one of [1] to [4] above, wherein the flame-retardant fabric contains, relative to the total weight of the fabric, 65 to 90% by weight of the acrylic fiber, 10 to 35% by weight of the regenerated cellulose fiber, and 0 to 10% by weight of other fibers.

[0107] [7] According to the flame-retardant fabric described in [5] or [6] above, wherein the regenerated cellulose fiber is selected from one or more of lyocell fiber and flame-retardant lyocell fiber.

[0108] [8] The flame-retardant fabric according to any one of [1] to [4] above, wherein the flame-retardant fabric contains, relative to the total weight of the fabric, 80 to 90% by weight of the acrylic fibers and 10 to 20% by weight of the natural cellulose fibers.

[0109] [9] The flame-retardant fabric according to any one of [1] to [4] above, wherein the flame-retardant fabric contains, relative to the total weight of the fabric, 70 to 90% by weight of the acrylic fiber, 10 to 20% by weight of the natural cellulose fiber, and 0 to 10% by weight of other fibers.

[0110]

[10] According to the flame-retardant fabric described in [6] or [9] above, wherein the other fibers are selected from one or more of metal fibers, metal-plated fibers, copper compound coated fibers, conductive material added fibers, meta-aromatic polyamide fibers, polyoxadiazole fibers, polyimide fibers, polyamide-imide fibers, nylon fibers, polyester fibers, para-aromatic polyamide fibers and polyaromatic fibers, preferably meta-aromatic polyamide fibers.

[0111]

[11] The flame-retardant fabric according to any one of [1] to [4] above, wherein the flame-retardant fabric contains the acrylic fiber, the regenerated cellulose fiber and the natural cellulose fiber, and the weight ratio of the regenerated cellulose fiber and the natural cellulose fiber is regenerated cellulose fiber: natural cellulose fiber = 1:2 to 3:1.

[0112]

[12] The flame-retardant fabric according to any one of [1] to

[11] above, wherein the acrylic fiber is a solution-dyed fiber.

[0113]

[13] The flame-retardant fabric according to any one of [1] to

[12] above, wherein the magnesium compound contains one or more selected from magnesium oxide and magnesium hydroxide.

[0114]

[14] The flame-retardant fabric according to any one of [1] to

[13] above, wherein the flame-retardant fabric is a woven fabric.

[0115]

[15] A work garment that uses the flame-retardant fabric described in any one of [1] to

[14] above.

Claims

1. A flame-retardant fabric, comprising acrylic fibers and cellulose fibers, wherein, The cellulose-based fiber is selected from one or more types of regenerated cellulose-based fibers and natural cellulose-based fibers. The flame-retardant fabric contains, relative to the total weight of the fabric, 80-90% by weight of the acrylic fibers and 10-15% by weight of the cellulose fibers. The acrylic fiber contains magnesium hydroxide inside the fiber. The flame-retardant fabric contains 2.5 to 4.5% by weight of magnesium hydroxide relative to the total weight of the fabric. The flame-retardant fabric, as determined by the flammability test based on ISO 15025:2000, has an afterflame time of less than 2 seconds and an afterglow time of less than 2 seconds.

2. The flame-retardant fabric according to claim 1, wherein, The acrylic fiber comprises an acrylonitrile copolymer, wherein the acrylonitrile copolymer contains acrylonitrile: 30-85% by weight, one or more halogenated monomers selected from halogenated vinyl monomers and halogenated vinylidene monomers: 15-65% by weight, and sulfonic acid-containing vinyl monomers: 0-3% by weight.

3. The flame-retardant fabric according to claim 1 or 2, wherein, The acrylic fiber contains 2.8 to 6.7% by weight of magnesium hydroxide inside the fiber.

4. The flame-retardant fabric according to claim 1 or 2, wherein, The regenerated cellulose fiber is selected from one or more of the following: rayon fiber, flame-retardant rayon fiber, lyocell fiber, and flame-retardant lyocell fiber.

5. The flame-retardant fabric according to claim 1 or 2, wherein, The flame-retardant fabric contains, relative to the total weight of the fabric, 80-90% by weight of the acrylic fibers and 10-15% by weight of the regenerated cellulose fibers.

6. The flame-retardant fabric according to claim 1, wherein, The flame-retardant fabric contains, relative to the total weight of the fabric, 80-90% by weight of the acrylic fibers, 10-15% by weight of the regenerated cellulose fibers, and 0-10% by weight of other fibers.

7. The flame-retardant fabric according to claim 5, wherein, The regenerated cellulose fiber is selected from one or more types of lyocell fiber and flame-retardant lyocell fiber.

8. The flame-retardant fabric according to claim 1 or 2, wherein, The flame-retardant fabric contains, relative to the total weight of the fabric, 80-90% by weight of the acrylic fibers and 10-15% by weight of the natural cellulose fibers.

9. The flame-retardant fabric according to claim 1, wherein, The flame-retardant fabric contains, relative to the total weight of the fabric, 80-90% by weight of the acrylic fibers, 10-15% by weight of the natural cellulose fibers, and 0-10% by weight of other fibers.

10. The flame-retardant fabric according to claim 6 or 9, wherein, The other fibers are selected from one or more of the following: metal fibers, metal-plated fibers, copper compound coated fibers, conductive material-added fibers, meta-aromatic polyamide fibers, polyoxadiazole fibers, polyimide fibers, polyamide-imide fibers, nylon fibers, polyester fibers, para-aromatic polyamide fibers, and polyaromatic fibers.

11. The flame-retardant fabric according to claim 1 or 2, wherein, The flame-retardant fabric contains the acrylic fiber, the regenerated cellulose fiber, and the natural cellulose fiber, wherein the weight ratio of the regenerated cellulose fiber to the natural cellulose fiber is 1:2 to 3:

1.

12. The flame-retardant fabric according to claim 1 or 2, wherein, The acrylic fiber is a solution-dyed fiber.

13. The flame-retardant fabric according to claim 1 or 2, wherein, The flame-retardant fabric is a woven material.

14. A work garment that uses the flame-retardant fabric as described in any one of claims 1 to 13.

Images