JP5807456B2 - Polyamide 410 fiber and fiber structure comprising the same - Google Patents

Description

The present invention relates to a polyamide 410 fiber and a fiber structure comprising the same. More specifically, the present invention relates to a polyamide 410 fiber having good fiber properties such as tensile strength, tensile elongation, boiling water shrinkage, and fineness fluctuation value, and a fiber structure comprising the same.

  Polyamide fibers typified by nylon 6 and nylon 66 make use of properties such as good mechanical properties, excellent wear resistance, and excellent flexibility, and are used for clothing (for example, stockings, innerwear, swimwear, skiwear). It is used in a wide range of fields such as sports clothing), automobile materials, marine products, and industrial materials.

  Nylon 6 and nylon 66, which are currently widely used, generally have a high water absorption rate, have large physical property changes and dimensional changes due to water absorption, and cannot be used in specific environments such as underwater or in a high humidity environment. I was receiving. On the other hand, examples of the polyamide resin having a low water absorption include nylon 11 (melting point 187 ° C.), nylon 12 (melting point 178 ° C.), nylon 610 (melting point 225 ° C.) and the like. ) Or less, it has been restricted for use in high temperature environments.

  Patent Documents 1 and 2 exemplify polyamide 4N (N = 7 or more) resin containing tetramethylenediamine as a constituent component. This document mainly discloses injection molded articles of polyamide 49, 410, 412 resins. Moreover, in patent document 3, the polyamide fiber which uses sebacic acid as a structural component is illustrated.

JP 2011-94103 A International Publication No. 2010/098335 JP 2010-25518 A

  However, none of these Patent Documents 1 to 3 disclose a specific example of actually producing polyamide 410 fiber, nor does it disclose any fiber obtained by spinning polyamide 410 resin. .

  An object of the present invention is to provide a polyamide 410 fiber that is excellent in fiber physical properties and can be suitably used in apparel use, industrial material use, and the like, and a fiber structure composed thereof.

  As a result of intensive studies to solve the above problems, the present inventors have succeeded in obtaining polyamide 410 fibers excellent in fiber physical properties, heat resistance and the like, and have completed the present invention.

  That is, the gist of the present invention is as follows.

The first invention in the present invention is a fiber comprising a polyamide resin obtained by polycondensation of an aliphatic amine containing tetramethylenediamine as a main component and a carboxylic acid containing sebacic acid as a main component, Strength 3-10 cN / dtex, tensile elongation 15-50%, boiling water shrinkage 3-15%, fineness variation (U%) 0.1-3.0% , tensile strength and elongation values The polyamide 410 fiber is characterized in that the toughness obtained from the obtained toughness and knot strength and elongation value is 65 ≦ [(toughness at the time of knot) / (toughness at the time of tension)] × 100 ≦ 100 .

The second invention is a polyamide 410 fiber structure characterized by containing a polyamide 410 fibers according to the first invention.

  The polyamide 410 fiber of the present invention not only has excellent tensile strength, tensile elongation, boiling water shrinkage, and fineness variation, but also has very high heat resistance because of its high melting point. In addition, since the toughness drop in the nodule state is small, it has durability enough to withstand practical use. Furthermore, the physical properties of the fiber are not significantly lowered even under wet conditions or at high temperatures, and it has excellent durability even under harsh environments such as in water or high temperatures, and can be suitably used for clothing and industrial materials.

FIG. 1 is a view showing an embodiment of an apparatus used for producing the polyamide 410 fiber of the present invention. FIG. 2 is a view showing an embodiment of an apparatus used for producing the polyamide 410 fiber of the present invention.

  Hereinafter, the polyamide 410 fiber of the present invention and the fiber structure comprising the same will be described in detail.

  The polyamide 410 resin used in the present invention is obtained by polycondensation of an aliphatic amine containing tetramethylenediamine as a main component and a carboxylic acid containing sebacic acid as a main component.

  The polyamide 410 resin used in the present invention preferably contains polyamide 410 in which 90 mol% or more of repeating units are composed of tetramethylene sebacamide units. In the range not impairing the effects of the present invention, for example, other copolymer components of 10 mol% or less may be included, but by containing a large amount of tetramethylene sebacamide units, regularity of molecular chains of the resulting fiber Is increased, and orientation crystallization is facilitated in the yarn making process, so that the fiber is excellent in mechanical properties, boiling water shrinkage, and heat resistance. The tetramethylene sebacamide unit is more preferably 95 mol% or more, and still more preferably 98 mol% or more.

  In addition to tetramethylenediamine and sebacic acid, the polyamide 410 resin used in the present invention may be copolymerized with other compounds within a range that does not impair the object of the present invention. For example, a structure derived from the following components: Units may be included. For example, ethylenediamine, 1,3-diaminopropane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane 1,11-diaminoundecane, 1,12-diaminododecane, 1,13-diaminotridecane, 1,14-diaminotetradecane, 1,15-diaminopentadecane, 1,16-diaminohexadecane, 1,17-diaminohepta Aliphatic diamine such as decane, 1,18-diaminooctadecane, 1,19-diaminononadecane, 1,20-diaminoeicosane, 2-methyl-1,5-diaminopentane, cyclohexanediamine, bis- (4-amino Cyclohexyl) alicyclic diamines such as methane, xylile Aromatic diamines such as diamine, amino acids such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and paraaminomethylbenzoic acid, lactams such as ε-caprolactam and ω-laurolactam, oxalic acid and malonic acid Aliphatic dicarboxylic acids such as succinic acid, glutaric acid and adipic acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, etc. Can be mentioned.

  The polyamide 410 resin used in the present invention preferably has a relative viscosity of sulfuric acid of 2.0 to 5.0, which is an index of molecular weight. The higher the relative viscosity of sulfuric acid, that is, the higher the molecular weight, the higher the strength of the resulting fiber, which is preferable. This is not only because of the high molecular weight, but the amount of molecular chain ends per unit volume (which tends to cause structural defects in the fiber) is reduced, and because the molecular chain length is long, there is more one molecular chain. Interacts with the molecular chains (physical entanglement, hydrogen bonds, van der Waals forces, etc.), and the spinning and stretching stresses are transmitted uniformly, so the molecular chains are uniformly oriented in the fiber manufacturing process. This is probably because of this. On the other hand, when the relative viscosity of sulfuric acid is in an appropriate range, melt spinning at an appropriate spinning temperature is possible, and the thermal decomposition of the polymer in the spinning machine is suppressed, so that the spinning property is improved, and the fiber coloring and mechanical properties are improved. It is preferable because deterioration of the mechanical characteristics can be suppressed. The relative viscosity of sulfuric acid is more preferably 2.2 to 4.8, still more preferably 2.5 to 4.5. The sulfuric acid relative viscosity here is a value measured by a method described later.

  Furthermore, the polyamide 410 resin used in the present invention preferably has a dispersity (Mw / Mn), which is an index of molecular weight distribution, of 1.5 to 3.0. Here, Mw is a weight average molecular weight, Mn is a number average molecular weight, and the smaller the Mw / Mn that is the ratio of both, the narrower the molecular weight distribution is. In addition to the high relative viscosity of sulfuric acid as described above, it is preferable to use a resin having a narrow molecular weight distribution with a Mw / Mn of 3.0 or less because the fiber has good fiber properties and low boiling water shrinkage. This is because Mw / Mn is small, that is, the distribution of molecular chain length is small, the number of molecular chains that interact with each other and the interaction force (physical entanglement force, hydrogen bonding force, fan) (Derwals force, etc.) are almost equal, so in the spinning process, each molecular chain is equally spun and stretched. As a result, the amorphous molecular chains are uniformly oriented and highly oriented crystals. It is estimated that many phases are formed. Furthermore, due to the effect that the molecular chains are uniformly oriented, the amorphous phase has many amorphous chains (tie molecules) that connect the crystal phases, and the molecular chain lengths of the tie molecules are also relatively equal. Many of them are presumed to exist in a tension state (movement is restricted by the crystal phase). That is, since it contains a lot of densely oriented crystal phases and these crystal phases are connected by many tension tie molecules, these act synergistically and have high strength, and the boiling water shrinkage rate is small. Presumed to be polyamide 410 fiber. When Mw / Mn is 3.0 or less, generation of low molecular weight compounds such as oligomers and pyrolysis gas can be suppressed during fiber formation by melt spinning, and spinnability and production environment are not deteriorated. Mw / Mn is more preferably 2.8 or less, further preferably 2.6 or less. Mw / Mn is preferably as small as possible, but may be 1.5 or more.

  With respect to the polyamide 410 resin used in the present invention, when the relative viscosity of sulfuric acid after melting and staying at melting point + 20 ° C. for 30 minutes is B and the relative viscosity of sulfuric acid before staying is A, the B / A value is 0.7 to 1. 5 is preferable. The B / A value is an indicator of melt residence stability. When the B / A value is less than 0.7, the polyamide 410 resin undergoes significant thermal decomposition during melt spinning, resulting in coloration of the resulting fiber or degradation of fiber properties. Or melt spinnability is greatly reduced. Further, when the B / A value is larger than 1.5, the viscosity increases due to the melt retention, and therefore melt spinnability is greatly deteriorated by foreign matters such as gel generated during the retention. The B / A value is more preferably 0.8 to 1.3, and still more preferably 0.9 to 1.2.

  The polyamide 410 resin used in the present invention preferably has a high melting point that serves as an index of heat resistance. The melting point is preferably 230 ° C. or higher, and more preferably 240 ° C. or higher.

  Further, the polyamide 410 resin used in the present invention can contain other polyamide resins and other polymers depending on the required properties within the range not impairing the object of the present invention. Specific examples of other polyamide resins include polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polytetramethylene adipamide (nylon 46), polypentamethylene adipamide (nylon 56). , Polypentamethylene sebacamide (nylon 510), polyhexamethylene sebacamide (nylon 610), polyhexamethylene dodecamide (nylon 612), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (nylon 66 / 6T), polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6T / 6I), polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (Nylon 6T / 6I), polyxylylene adipamide (nylon XD6), and mixtures thereof or copolymers, and the like. Among them, preferred examples include nylon 6, nylon 66, nylon 610, nylon 6/66 copolymer, nylon 6/12 copolymer and the like. Specific examples of the other polymers include polyethylene, polypropylene, polyester, polycarbonate, polyphenylene ether, polyphenylene sulfide, liquid crystal polymer, polysulfone, polyethersulfone, ABS resin, SAN resin, and polystyrene.

  The polyamide 410 resin used in the present invention has other components such as antioxidants and heat stabilizers (hindered phenols, hydroquinones, phosphites, and substituted products thereof, as long as the object of the invention is not impaired. Copper halides, iodine compounds, etc.), weathering agents (resorcinol, salicylate, benzotriazole, benzophenone, hindered amine, etc.), lubricants (aliphatic alcohol, aliphatic amide, aliphatic bisamide, bisurea, polyethylene wax, etc.) ), Pigment (cadmium sulfide, phthalocyanine, carbon black, etc.), dye (nigrosine, aniline black, etc.), plasticizer (octyl p-oxybenzoate, N-butylbenzenesulfonamide, etc.), antistatic agent (alkyl sulfate anion) -Based antistatic agent, quaternary ammonia Salt-type cationic antistatic agents, nonionic antistatic agents such as polyoxyethylene sorbitan monostearate, betaine amphoteric antistatic agents), flame retardants (melamine cyanurate, magnesium hydroxide, aluminum hydroxide, etc.) Phosphorus flame retardants such as hydroxide, ammonium polyphosphate, melamine polyphosphate, metal phosphinate, brominated polystyrene, brominated polyphenylene oxide, brominated polycarbonate, brominated epoxy resins or their brominated flame retardants and trioxide A combination with antimony etc.) can be added at any time.

  As a method for producing the polyamide 410 resin used in the present invention, there is a method in which tetramethylenediamine and sebacic acid or a salt thereof are heated to synthesize a low-order condensate and then subjected to solid phase polymerization or melt high polymerization. Can be mentioned. In this method, a low-order condensate is taken out once, followed by a two-stage polymerization method in which solid-phase polymerization or a high degree of melt polymerization is performed. Either one-stage polymerization method may be used.

  The polyamide 410 resin obtained by melt polymerization has a narrow molecular weight distribution (Mw / Mn) compared to the polyamide 410 resin obtained by solid phase polymerization, and the content of low molecular weight components is relatively small. It is more preferable because mechanical properties such as tensile strength and tensile elongation are improved. The low-order condensate is defined as polyamide 410 resin having a sulfuric acid relative viscosity of 1.05-1.90. Heat polycondensation is defined as a production process that raises the maximum temperature of the polyamide 410 resin during production to 180 ° C. or higher. Solid-phase polymerization refers to a step of heating in a temperature range from 100 ° C. to the melting point under reduced pressure or in an inert gas, and melt-polymerization refers to a step of heating to a melting point or higher under normal pressure or reduced pressure.

  When the polyamide 410 resin used in the present invention is produced, the polymerization proceeds due to volatilization of tetramethylene diamine and pyrrolidine produced by the cyclization reaction or pyrrolidine as a terminal blocker. Along with this, the total amino group amount with respect to the total carboxyl group amount in the polymerization system decreases, and the polymerization rate tends to be delayed. In the present invention, in order to suppress the volatilization of tetramethylenediamine, it is preferable that the pressure in the polymerization system is high. However, when the volatilization of condensed water is suppressed, the cyclization reaction of tetramethylenediamine is promoted. In the present invention, the maximum pressure in the polymerization system is preferably 0.1 to 2.5 MPa. More preferably, it is 0.2-2.0 MPa, More preferably, it is 0.2-1.5 MPa, Most preferably, it is 0.3-1.0 MPa. When the pressure is less than 0.1 MPa, the volatilization of tetramethylenediamine cannot be sufficiently suppressed, and the equimolarity of the amino group and the carboxyl group tends to be greatly broken. On the other hand, when the pressure exceeds 2.5 MPa, water desorption due to polycondensation is suppressed, and the degree of polymerization tends not to increase. As the condensation reaction proceeds, condensed water is generated and the pressure in the system rises, so the pressure at the start of polymerization may be zero, but in order to minimize the volatilization of tetramethylenediamine, The pressure in the system can be adjusted to be high by a method of adding water or a method of pressurizing with an inert gas in advance at the start of polymerization.

  In addition, in order to obtain a high molecular weight polyamide 410 resin, it is preferable to add a specific amount of tetramethylenediamine in advance at the stage of charging the raw material to control the amount of amino groups in the polymerization system. It is preferable to adjust the raw material composition ratio so that the ratio a / b is 1.005 to 1.07, where a is the number of moles of tetramethylenediamine used as the raw material and b is the number of moles of sebacic acid. More preferably, the raw material composition ratio is adjusted to 1.01 to 1.06. When a / b is less than 1.005, the total amino group amount in the polymerization system is extremely smaller than the total carboxyl group amount, and it tends to be difficult to obtain a high molecular weight polymer. On the other hand, when a / b is larger than 1.07, the total amount of carboxyl groups in the polymerization system is extremely smaller than the total amount of amino groups, and it tends to be difficult to obtain a high molecular weight polymer. Furthermore, the volatilization amount of the diamine component increases, which is not preferable from the viewpoint of productivity and environment.

  In the heat polycondensation of the polyamide 410 resin used in the present invention, in order to prevent coloration in addition to the volatilization of tetramethylenediamine and the suppression of cyclization due to the deammonification reaction, the thermal history that the polymer undergoes throughout the polymerization process. It is important to make the temperature as small as possible, and as a means for this, it is effective to lower the maximum temperature reached in the polymerization system. In the present invention, when the low-order condensate is melted and highly polymerized, the maximum temperature within the polymerization system is preferably not less than the melting point of the polyamide resin and not more than 285 ° C., more preferably not less than the melting point and melting point +30. It is below ℃. When the temperature is higher than 285 ° C., volatilization and cyclization of tetramethylenediamine are promoted, and the resulting polyamide 410 resin tends to be colored. In the case of increasing the degree of polymerization in the solid phase, it is preferable to perform solid phase polymerization at a melting point of −40 ° C. or higher and lower than the melting point under reduced pressure or in an inert gas atmosphere.

  The tensile strength of the polyamide 410 fiber of the present invention is 3 to 10 cN / dtex. If the tensile strength is 3 cN / dtex or more, the passability and handleability of high-order processing processes such as weaving and knitting are improved, and even if the weaving tension in the weaving process is increased, fluff is less likely to occur and the density is high. This is preferable because a woven fabric can be obtained with good processability. The tensile strength is more preferably 3.5 cN / dtex or more, and further preferably 4.0 cN / dtex or more. Higher strength is more preferable, but if an excessively high strength fiber is to be produced, yarn breakage or fluff tends to occur easily in the spinning process or the drawing process. Therefore, the tensile strength is more preferably 9.5 cN / dtex or less, and further preferably 9.0 cN / dtex or less.

  The tensile elongation of the polyamide 410 fiber of the present invention is 15-50%. By setting the tensile elongation to 15% or more, generation of fluff can be suppressed in the spinning and drawing processes, and the processability such as twisting, warping, weaving, and knitting processes after the spinning and drawing processes can be suppressed. Will improve. Further, it is preferably 50% or less in order to suppress deformation of the fiber under low stress and to prevent dyeing defects in the final product due to wetting marks during weaving. The tensile elongation is more preferably 17 to 48%, still more preferably 20 to 45%.

  The boiling water shrinkage of the polyamide 410 fiber of the present invention is 3 to 15%. It is preferable that the boiling water shrinkage is 15% or less because the degree of orientation of molecular chains is not extremely reduced during the treatment with boiling water, and the strength is not lowered after the treatment. Moreover, since the fiber can be sufficiently shrunk by the process of thermally shrinking the fabric, it is preferable because a flexible fabric can be obtained. On the other hand, since the boiling water shrinkage rate is 3% or more, it is possible to increase the weaving density by heat shrinking the fabric, and to produce a high-density fabric while keeping the weaving tension in the weaving process within an appropriate range. preferable. This eliminates the need for weaving under high tension in the production of a high-density fabric, so that the generation of fluff and sink marks in the weaving process can be suppressed, and a fabric with few defects can be produced with good processability.

  The fineness fluctuation value (U%: Normal mode) of the polyamide 410 fiber of the present invention is 0.1 to 3.0%. The fineness variation value (U%) is an index of thickness unevenness in the fiber longitudinal direction, and can be obtained by a Worcester tester manufactured by Zerbegger Worcester. The smaller the fineness variation value (U%), the smaller the thickness unevenness in the longitudinal direction of the fiber. If it is 3.0% or less, the uniformity in the longitudinal direction of the fiber is excellent, and the warping process or weaving Because it is possible to suppress fluctuations in processing tension during the knitting process, fluff and thread breakage are less likely to occur, and even when dyeing is performed, defects such as partially strong dyed spots and dyed streaks may occur. It becomes a high-grade fabric. The fineness variation value (U%) is preferably as small as possible, more preferably 2.5% or less, and still more preferably 2.0% or less. On the other hand, regarding the lower limit, it is practically difficult to obtain fibers of less than 0.1%.

The polyamide 410 fiber of the present invention is preferable in that it has not only good toughness but also has a property of suppressing a decrease in toughness even in a knotted state. In a preferred embodiment, the toughness obtained from the tensile strength / elongation value and the knot strength / elongation value can satisfy the following formula (1).
Formula (1) 65 ≦ [(toughness at the time of knot) / (toughness at the time of tension)] × 100 ≦ 100

  Toughness simply indicates the energy when the fiber breaks. If the toughness is high, the fiber is difficult to break, and the toughness is represented by the product of the square root of the strength [cN / dtex] and the elongation [%] (that is, the strength × the 0.5th power of the elongation). In the test in the nodule state, unlike the simple tensile test, the elements of tension, compression, bending and torsion are intertwined in a complicated way, and the strength (nodule strength) and elongation (nodule elongation) obtained from this measurement are practically important. In particular, the knot strength is an index representing the “brittleness” of the fiber. If the value of the above formula (1) is 65% or more, the brittleness of the fiber is low, and it has durability enough to withstand practical use. The value of formula (1) is preferably as high as possible, but is preferably 70% or more, and more preferably 75% or more.

  The polyamide 410 fiber of the present invention is preferable in that it has a property of suppressing a decrease in tensile strength when wet. In a preferred embodiment, the dry / wet tensile strength ratio can be 90% or more. The dry / wet tensile strength ratio [%] is a value obtained from {(wet tensile strength ratio) / (tensile strength ratio)} × 100. The higher this number is, the smaller the decrease in strength when wet. When it is 90% or more, strength reduction is sufficiently suppressed even under water or in a high humidity environment, and it becomes possible to impart excellent durability to the product. The dry / wet tensile strength ratio is preferably 93% or more, more preferably 95% or more. The term “wet” as used above refers to a wet test in JIS L1013 (1999) 8.5.2, and a fiber sample (40 cm in length, the number corresponding to the number of measurements) used for measurement is placed in a container ( It is placed in a stainless steel vat) and immersed in 1 liter of water (temperature 20 ± 2 ° C.) for 60 minutes to mean that the fiber sample has been sufficiently wetted.

  The polyamide 410 fiber of the present invention is preferable in that it has a characteristic that a decrease in tensile strength is suppressed even after dry heat treatment. In a preferred embodiment, the strength retention after the dry heat treatment can be 45% or more. The strength retention [%] after dry heat treatment is a value obtained from [(tensile strength after 180 ° C. dry heat treatment) / (tensile strength before treatment)] × 100. The higher this number, the smaller the rate of strength reduction at high temperatures. Since the strength retention of the existing polyamide 66 fiber is about 40%, when the strength retention is 45% or more, it is possible to impart excellent high temperature durability to the product even at high temperatures. The strength retention after the dry heat treatment is preferably 50% or more, more preferably 55% or more. The dry heat treatment referred to here means that a casserole made with 10 turns using a 1 m / circular measuring instrument is stored in an environment of a temperature of 20 ° C. and a relative humidity of 65% for 24 hours or more, and then a temperature of 180 °. It means heat treatment with a hot air dryer at 15 ° C. for 15 minutes.

  Although the total fineness of the polyamide 410 fiber of this invention can be arbitrarily set according to the objective use in garment use and industrial material use, it is preferable that it is 20-600 dtex. When the total fineness is 600 dtex or less, even a high-density fabric is a thin fabric with high flexibility. On the other hand, a total fineness of 20 dtex or more is preferable because it can sufficiently withstand practical use. The total fineness is more preferably 25 to 550 dtex, and further preferably 30 to 500 dtex.

  About the fineness of the single fiber of the polyamide 410 fiber of this invention, although it can set arbitrarily according to a required characteristic, it is preferable that it is 0.1-20.0 dtex. As the fineness of the single fiber is smaller, the bending rigidity of the single fiber is lowered, so that the bending rigidity of the fiber (multifilament) is lowered. As a result, the knitted or knitted fabric is also increased in flexibility, so that it is 20.0 dtex or less. It is preferable. On the other hand, when the fineness of the single fiber is 0.1 dtex or more, it becomes possible to perform high-magnification drawing while suppressing the generation of fuzz in the yarn production process, so that it has high strength and shrinks even in boiling water treatment. Since it becomes difficult fiber, it is preferable. The fineness of the single fiber is more preferably 0.5 to 15.0 dtex, and further preferably 1.0 to 10.0 dtex.

  In addition, what is necessary is just to select the filament number of the polyamide 410 fiber of this invention according to the objective use in the range used as said total fineness and single fiber fineness, but it is preferable that it is the range of 5-1000.

  The cross-sectional shape of the polyamide 410 fiber of the present invention can be arbitrarily set according to the required characteristics, but typically, a perfect circular shape or an elliptical shape having substantially no unevenness can be employed. Various irregular cross-sectional shapes such as polygonal cross sections such as trilobes, four lobes, five lobes, six lobes, and eight lobes, flat cross sections, and hollow cross sections having one or more hollow portions inside the fibers can also be adopted. .

  Next, the method for producing polyamide 410 fibers of the present invention will be described.

  Using the polyamide 410 resin produced as described above, an undrawn yarn can be obtained by a specific spinning method, and then subjected to drawing to obtain the polyamide 410 fiber of the present invention.

  In the present invention, it is preferable that the polyamide 410 resin is heat-dried to have a moisture content of 1000 ppm or less before melt spinning before melt spinning. By the way, in a normal polyamide 66 resin, if the moisture content is excessively low, gelation is induced in melt storage, and there is a tendency to cause yarn breakage. However, in polyamide 410 resin, gelation is unlikely to occur, and heat deterioration in melt storage is caused. In order to suppress it, the moisture content is preferably as low as possible. The moisture content is more preferably 600 ppm or less, and further preferably 400 ppm or less. The reason why the polyamide 410 resin is less likely to be gelled at the time of melt storage than the polyamide 66 resin is not clear, but is thought to be due to the short number of carbon atoms in the methylene chain to which the amino terminal group is bonded. In other words, in the polyamide 66 resin, since the amino terminal group is bonded to the methylene chain having 6 carbon atoms, the molecular chain in the vicinity of the amino terminal is easy to return, and when it is thermally decomposed, the returned product is released and induces gelation. On the other hand, in the polyamide 410 resin, since the methylene chain has 4 carbon atoms, it is estimated that gelation hardly occurs due to steric hindrance and hardly gels.

  Next, the dried pellet is fiberized in a spinning process. 1 and 2 are views showing an embodiment of an apparatus used for producing the polyamide 410 fiber of the present invention. After the polyamide 410 resin is melted by the extruder 1 and weighed by the metering pump 2, it is sent to the spinning pack 4 built in the spinning block 3, the polymer is filtered in the pack, and then spun from the spinneret 5. Obtain the thread 6 The spun yarn 6 that has been spun is once cooled and solidified by a cooling device 7, and then an oil agent is applied by an oil supply device 8, and then taken up by a first godet roll 10, and wound through a second godet roll 11. A take-up yarn (undrawn yarn) 13 can be obtained by being taken up by the take-up machine 12. The fibers may be entangled using the entanglement imparting device 9 at any stage before winding, for example, above the first godet roll 10 or between the first godet roll 10 and the second godet roll 11. What is necessary is just to adjust the frequency | count of a confounding process and process pressure so that CF value of a fiber may be set to 3-30.

  Thereafter, the undrawn yarn 13 is drawn in a range of 2.0 to 5.0 times using a drawing machine having a configuration as shown in FIG. That is, the undrawn yarn 13 is heated through the supply roll 14 and then heated on the first heating roll 15 set to a predetermined temperature, using the speed ratio with the second heating roll 16 set to the predetermined temperature. Stretched (stretching: first stage). Subsequently, the film is stretched using a speed ratio between the second heating roll 16 and the third heating roll (final heating roll) 17 set to a predetermined temperature (stretching: second stage). The fiber that has exited the third heating roll (final heating roll) 17 is wound up as a drawn yarn pann 19 via an unheated final roll (cold roll) 18. Thus, when extending | stretching by 2 steps | paragraphs, the last heating roll becomes the 3rd heating roll (final heating roll) 17. FIG. Moreover, when extending | stretching only one step between a 1st heating roll and a 2nd heating roll, since a 3rd heating roll is not used, a final heating roll turns into a 2nd heating roll. Moreover, when extending | stretching by 3 steps | paragraphs or more, the heating roll before a last roll (cold roll) turns into a final heating roll. The number of stretching stages may be one or more, and the stretching may be performed in two or more stages, and may be appropriately selected according to the intended use.

  The spinning temperature in melt spinning is preferably 260 to 320 ° C. It is preferable to set the spinning temperature to 320 ° C. or lower because thermal decomposition of the polyamide 410 resin can be suppressed. More preferably, it is 310 degrees C or less, More preferably, it is 300 degrees C or less. On the other hand, by setting the spinning temperature to 260 ° C. or higher, the polyamide 410 resin exhibits sufficient melt fluidity, the discharge amount between the discharge holes is made uniform, high-stretching is possible, and the spinnability is also improved. preferable. The spinning temperature is more preferably 270 ° C. or higher, and further preferably 280 ° C. or higher. Here, the spinning temperature refers to the temperature of the spinning block 3.

  The shape of the discharge hole in the spinneret may be selected according to the cross-sectional shape of the single fiber that constitutes the fiber to be manufactured.For example, in the case of a round cross-sectional yarn, the hole diameter is required to uniformly discharge the polymer between the single fibers. It is preferable to select 0.1 to 1.0 mm and the hole length in the range of 0.2 to 5.0 mm. It is also possible to take measures such as increasing the polymer meterability with the first die, with a plurality of spinnerets.

  As a method of cooling the spun yarn, a method of solidifying with a cooling air is preferable. The wind speed of the cooling air is preferably 0.3 to 1 m / sec. If the wind speed is within this range, the cooling spots of the yarn, the yarn swaying, etc. do not occur, and the fineness variation value is good. In addition, the spinning property is improved.

  The cooling start distance is preferably 3 to 30 cm from the die surface. A longer cooling start distance is preferable because the strength of the fiber increases. On the other hand, if the cooling start distance is excessively long, the cooling of the fiber becomes non-uniform and the fineness variation value (U%) is deteriorated. The cooling start distance is more preferably 5 to 20 cm. The cooling start distance refers to the distance from the base surface to the cooling air blowing part (uppermost part) of the cooling device.

  Alternatively, a heating cylinder may be provided between the base surface and the cooling start point to reheat the spun yarn, and then cooling with cooling air may be performed. Reheating with a heating cylinder is preferable because thinning in the high temperature range is induced and more uniform alignment occurs, and if the temperature of the heating cylinder is (spinning temperature + 20) ° C. to (spinning temperature + 100) ° C., spinning is performed. This is preferable because reheating of the yarn can be performed efficiently and thermal decomposition of the spun yarn can be suppressed.

  The spinning oil may be adhered straight to the yarn, but in order to adhere more uniformly, it is dispersed in water in an amount of 1 to 50% by weight, preferably 5 to 30% by weight and adhered to the fiber as a water emulsion oil. preferable. By attaching the spinning oil within this range, it is possible to suppress the abrasion resistance with the oiling device and the guide, etc., so that not only can the strength decrease of the resulting fiber and the occurrence of fluff be suppressed, but also the spinnability is dramatically improved. To do.

  An undrawn yarn can be obtained by taking out the spun yarn to which the oil agent is adhered, and the take-up speed at this time is preferably 300 to 2000 m / min. A take-up speed of 300 m / min or more is preferable because the spinning tension is moderately increased and the yarn fluctuation of the spun yarn is reduced. On the other hand, it is preferable to set the take-up speed within an appropriate range because drawing at a high magnification is possible and a fiber having high strength is obtained. The take-up speed is more preferably 500 to 1500 m / min, and further preferably 700 to 1200 m / min.

  In the stretching step, stretching is performed so that the obtained fiber has an elongation of 15 to 50%. What is necessary is just to select a draw ratio in the range of 2.0-5.0 times. By setting the draw ratio to 2.0 times or more, the tensile strength becomes sufficiently high, and stable drawing can be performed without deterioration of the fineness fluctuation value. Further, by setting the draw ratio to 5.0 times or less, it is possible to suppress a decrease in the tensile elongation of the obtained fiber and the generation of fluff, and stable drawing becomes possible. The stretching ratio refers to the ratio between the first heating roll and the final heating roll (that is, the stretching ratio is the ratio of final heating roll speed / first heating roll speed). The number of stretching steps may be one or may be stretched in multiple stages of two or more, and may be appropriately selected according to the intended use. Moreover, the temperature of a heating roll shall be 30-240 degreeC, and it is preferable that the temperature of a final heating roll is 150-240 degreeC especially. By setting the temperature of the final heating roll to 150 ° C. or higher, the molecular mobility of the oriented amorphous part can be increased and the molecular orientation can be effectively reconstructed. In addition, when the temperature is 240 ° C. or lower, fiber fusion on the heating roll does not occur, so that stretchability does not deteriorate, and excessive molecular mobility is suppressed, thereby suppressing molecular alignment spots in the fiber longitudinal direction. can do.

  After extending | stretching, it is preferable that a relaxation process is carried out by the speed ratio between the last heating roll and the last roll (cold roll). The relaxation treatment refers to a case where the relaxation magnification defined by the final roll speed / final heating roll speed is less than 1.00, and the relaxation magnification is preferably 0.85 to 0.99 times. When the relaxation ratio is 0.99 times or less, non-uniform distortion applied to the amorphous chain in the stretching process is averaged and the amorphous chain is stabilized, so the boiling water shrinkage of the resulting fiber is low. Therefore, it is preferable. More preferably, it is 0.97 times or less. The lower the relaxation magnification, the better. However, it is preferable to set the relaxation magnification to 0.85 or more because an appropriate yarn tension is expressed between the rolls and process passability is improved. More preferably, it is 0.87 or more.

  The polyamide 410 fiber of the present invention not only has excellent tensile strength, tensile elongation, boiling water shrinkage, and fineness variation, but also has very good heat resistance. In addition, since the toughness drop in the nodule state is small, it has durability enough to withstand practical use. In addition, the fiber physical properties decrease even under wet and high temperatures, which is small compared to existing polyamide fibers and has excellent durability even under harsh environments such as water and high temperatures, so it can be used as a wide variety of fiber structures. Out. For example, it can be a fabric (woven fabric, knitted fabric, non-woven fabric, pile fabric, etc.) or a string-like product (dip cord, rope, tape, fishing net, braided string, etc.), and is widely used in industrial materials and clothing. Also, for example, it is suitably used as a fiber structure (airbag, rubber reinforcing fiber, seat belt, seat, mat, etc.) constituting vehicle interior and exterior materials such as automobiles and aircrafts and safety parts. It is also suitable for industrial applications such as fishing nets, ropes, safety belts, slings, tarpaulins, tents, anchorages, braids, curing sheets, canvas, sewing threads, agricultural herbicidal sheets, and building material waterproof sheets. In addition, it is also suitably used in apparel applications that require strength and wear resistance, such as outdoor wear and sportswear.

  The fiber structure may contain fibers other than the polyamide 410 fiber. However, when the fiber structure is formed, the polyamide 410 fiber may be formed as a main component. It is preferable at the point which can provide a characteristic. That is, when only a polyamide 410 fiber is used to form a fiber structure, or the fiber structure is composed of a plurality of types of fibers, the polyamide 410 fiber has excellent characteristics among the plurality of fibers constituting the fiber structure. In order to make the most of it, it is preferable to contain 50% by weight or more of the polyamide 410 fiber, more preferably 70% by weight or more, and still more preferably 90% by weight or more.

  Examples of fiber structures composed of a plurality of types of fibers include fabrics mixed with elastic fibers such as polyurethane to give stretch properties, woven fabrics using polyamide 410 fibers only for warps or wefts, and cotton, silk, Natural fibers such as hemp and wool, recycled fibers such as viscose rayon and cupra rayon, semi-synthetic fibers such as cellulose acetate, synthetic fibers such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, nylon, acrylic, vinylon, polyolefin and polyurethane And twisting and composite processing.

  Hereinafter, the present invention will be described in detail with reference to examples. In addition, the measuring method in an Example used the following method.

A. Sulfuric acid relative viscosity Flowing time (T1) at 25 ° C. was measured using an Ostwald viscometer in 98% sulfuric acid at a concentration of 0.01 g / ml. Subsequently, the flow-down time (T2) of only 98% by weight sulfuric acid was measured. The ratio of T1 to T2, that is, T1 / T2, was defined as sulfuric acid relative viscosity. The number of measurements was three, and the average value was defined as sulfuric acid relative viscosity.

B. Melt retention stability evaluation (B / A)
It calculated | required using the sulfuric acid relative viscosity (B) of the sample obtained by hold | maintaining for 30 minutes at the temperature of melting | fusing point +20 degreeC in nitrogen atmosphere, and the sulfuric acid relative viscosity (A) before a test. The number of measurements was 3, and the average value was B / A.

C. Mw / Mn
Using Gel Permeation Chromatography (GPC), 2.5 mg of polyamide 410 resin was dissolved in 4 ml of hexafluoroisopropanol (0.005N sodium trifluoroacetate added) and filtered through a 0.45 μm filter. Was used for measurement, and the weight average molecular weight Mw and the number average molecular weight Mn were measured to calculate Mw / Mn. The number of measurements was 3, and the average value was Mw / Mn. The measurement conditions are as follows.
GPC device: Waters 515 (manufactured by Waters)
Column: Shodex HFIP-806M (two linked) + HFIP-LG
Solvent: hexafluoroisopropanol (0.005N-sodium trifluoroacetate added)
Temperature: 30 ° C
Flow rate: 0.5 ml / min Injection amount: 0.1 ml
Detector: Differential refractometer Waters 410 (manufactured by Waters)
Molecular weight calibration: polymethylmethacrylate.

D. Melting point The melting point was measured using a differential scanning calorimeter DSC-7 manufactured by Perkin Elmer. That is, 10 mg of the sample is heated up to 280 ° C. at a temperature rising rate of 16 ° C./min, and held for 5 minutes after the temperature rising. Thereafter, the sample was rapidly cooled and cooled to room temperature, and then again heated to 280 ° C. at a temperature rising rate of 16 ° C./min. In the differential calorimetric curve obtained by raising the temperature again, the peak showing the extreme value on the endothermic side was judged as the melting peak, and the temperature giving the extreme value was taken as the melting point (° C.). When a plurality of extreme values exist, the extreme value on the high temperature side was taken as the melting point. The number of measurements was 3, and the average value was taken as the melting point.

E. Moisture content The Karl Fischer coulometric titration moisture meter (Hiranuma Sangyo Co., Ltd. trace moisture measuring device AQ-2000 and the company's moisture vaporizer EV-200) was used. Using about 0.5 g of the sample, dry nitrogen gas was allowed to flow at a water vaporization temperature of 180 ° C., and the moisture content was measured. The number of measurements was 3, and the average value was taken as the moisture content.

F. Fineness [dtex] was obtained by collecting a skein having a total length of 100 m using a measuring machine having a fineness of 1 m / round, measuring the weight of the skein and multiplying it by 100. The number of measurements was 3, and the average value was defined as the fineness.

G. Tensile strength and tensile elongation Measured using JIS L1013 (1999), 8.5 tensile strength and elongation, 8.5.1 standard time test method, Shimadzu Autograph AG-50NISMS type did. A load-elongation curve was obtained with a gripping interval of 200 mm and a tensile speed of 200 mm / min. Next, the load value indicating the maximum point is divided by the fineness to obtain the tensile strength, the elongation at the maximum point load is divided by the initial sample length to obtain the tensile elongation, and the measurement is performed 10 times. Strength and tensile elongation were used. The measurement environment was a temperature of 20 ° C. and a relative humidity of 65%.

H. Nodule Strength and Nodular Elongation Measured using JIS L1013 (1999), nodule strength of 8.6, test method of 8.6.1 standard time test, using Autograph AG-50NISMS type manufactured by Shimadzu Corporation. A load-elongation curve was obtained with a gripping interval of 200 mm and a tensile speed of 200 mm / min. Next, the load value indicating the maximum point is divided by the fineness to obtain the nodule strength, the elongation at the maximum point load is divided by the initial sample length to obtain the nodule elongation, the measurement is performed 10 times, and the average value is calculated as the nodule. Strength and nodule elongation were used. The measurement environment was a temperature of 20 ° C. and a relative humidity of 65%.

I. (Toughness at the time of nodule) / (Toughness at the time of tension) × 100 value Using the tensile strength / elongation and the knot strength / elongation obtained in the G and H terms, the calculation was performed according to the following equation.
[{(Nodule strength) × (nodule elongation) ^1/2 } / {(tensile strength) × (tensile elongation) ^1/2 }] × 100

J. et al. Wet / wet tensile strength ratio Measured according to JIS L1013 (1999), 8.5 tensile strength and elongation, 8.5.2 wet test method using autograph AG-50NISMS type manufactured by Shimadzu Corporation . A fiber sample (length 40 cm, number corresponding to the number of measurements) to be measured is put in a container (stainless steel vat) and immersed in 1 liter of water (temperature 20 ± 2 ° C.) for 60 minutes to fully Moistened. Then, the load-elongation curve was calculated | required by setting the holding | grip space | interval to 200 mm and the tensile speed to 200 mm / min. Next, the load value indicating the maximum point was divided by the fineness to obtain the wet tensile strength, the measurement was performed 10 times, and the average value was taken as the wet tensile strength. The measurement environment was a temperature of 20 ° C. and a relative humidity of 65%. Using this wet tensile strength and the tensile strength obtained by the above G term, the dry / wet tensile strength ratio was calculated by the following equation.
Dry / wet tensile strength ratio [%] = {(wet tensile strength ratio) / (tensile strength ratio)} × 100

K. Boiling water shrinkage In an environment with a temperature of 20 ° C. and a relative humidity of 65%, a casserole (10 turns) was prepared using a measuring instrument of 1 m / lap and stored for 24 hours or more. Thereafter, the raw length L0 was measured under the environment, and then treated with boiling (98 ° C.) water for 15 minutes under no weight. The treated casserole was air-dried overnight, and then L1 was measured. The boiling water shrinkage was determined. The number of measurements was 3, and the average value was defined as the boiling water shrinkage.
Boiling water shrinkage [%] = [(L0−L1) / L0)] × 100
L0: Raw sample measured with sample taken and measured under initial load of 0.09 cN / dtex L1: Case with measured load of L0 treated in boiling water for 15 minutes, air-dried overnight, then initial load of 0. Length of casserole under 09 cN / dtex.

L. Fineness variation (U%)
The U% measurement was obtained by measuring under the following conditions using a Worcester tester 4-CX manufactured by Zerbegger Worcester. The number of measurements was 5, and the average value was U%.
Measurement speed: 200 m / min Measurement time: 2.5 minutes Measurement fiber length: 500 m
Twist: S twist, 12000 / m

M.M. Strength retention after dry heat treatment In an environment with a temperature of 20 ° C and a relative humidity of 65%, a casserole (10 turns) was prepared using a measuring machine of 1 m / lap, stored for 24 hours or more, and then 180 ° C Was subjected to a dry heat treatment for 15 minutes under no load in a hot air dryer set to 1. Thereafter, the fineness and tensile strength / elongation values of the treated casserole were determined by the following methods. The number of tensile strength / elongation measurements was 10, and the average value was taken as the strength after dry heat treatment.
Fineness of casserole after treatment: The weight per meter was measured, and a value obtained by multiplying the value by 10,000 was defined as fineness.
Tensile strength / elongation: measured by the same method as G term

From the obtained characteristic values, the strength retention after the dry heat treatment was calculated using the following formula.
Strength retention [%] = [(Tensile strength after 180 ° C. dry heat treatment) / (Tensile strength before treatment)] × 100

N. Evaluation of the number of fluffs of the drawn yarn A fluff tester (DT-104 type) manufactured by Toray Industries, Inc. was used to measure the number of fluffs per 10,000 m.
○: The number of fluff is 0.
Δ: The number of fluff is 1-2.
X: The number of fluff is 3 or more.

O. Evaluation of spinnability When melt-spinning 3 kg of polymer, three-stage evaluation was performed based on the number of yarn breaks.
○: No thread breakage occurred.
Δ: Yarn breakage occurred once or twice.
X: The yarn breakage occurred 3 times or more.

P. Evaluation of stretchability A three-stage evaluation was performed based on the number of yarn breaks that occurred when 100 g of drawn yarn was prepared.
○: No thread breakage occurred.
Δ: Yarn breakage occurred once or twice.
X: The yarn breakage occurred 3 times or more.

Reference Example 1 Preparation of Nylon 410 Salt 15 parts by weight of sebacic acid (Tokyo Kasei) was added to 150 parts by weight of ethanol and dissolved by being immersed in a 60 ° C. water bath. A solution prepared by dissolving 6.54 parts by weight of tetramethylenediamine (Kanto Chemical) in 80 parts by weight of ethanol was added dropwise over 1 hour. After stirring for 3 hours, the mixture was left standing at room temperature to precipitate the deposited salt. Thereafter, filtration and ethanol washing were performed, followed by vacuum drying at 50 ° C. for 24 hours to obtain nylon 410 salt.

Example 1
10 parts by weight of nylon 410 salt prepared in Reference Example 1 and 0.612 parts by weight of tetraethylenediamine 10% by weight aqueous solution are placed in a test tube, charged in a pressure vessel and purged with nitrogen, and then the pressure in the can is 0.59 MPa with nitrogen. Pressurized. The sealed pressure vessel was set to a heater temperature of 235 ° C. and heating was started. After 5 hours, the internal temperature of the can reached 191 ° C. and the internal pressure of the can reached 1.10 MPa. Subsequently, the heater set temperature was changed to 270 ° C., the pressure release was started, and the pressure inside the can was made zero over 2 hours while distilling water. At this time, the inside temperature of the can was 230 ° C. Furthermore, the temperature in the can reached 254 ° C. by holding for 2 hours under a nitrogen flow. The pressure vessel was cooled to room temperature, and the solid content was pulverized with a freezer mill to obtain nylon 410 resin (sulfuric acid relative viscosity 3.50).

  This nylon 410 resin was vacuum dried at 105 ° C. for 12 hours (moisture content after drying: 220 ppm), then supplied to a twin screw extruder and melted, and a spinneret (discharge hole diameter 0.3 mm, hole length at a spinning temperature of 290 ° C. 0.75 mm, 18 holes). The spun yarn is cooled by cooling air having a wind temperature of 20 ° C. and a wind speed of 0.5 m / second, and is made to converge by applying an oil agent with an oil supply device, and taken up by a first godet roll (spinning speed of 750 m / min). It wound up with the winder via the 2nd godet roll rotated at the same speed as the 1st godet roll (undrawn yarn: Fineness 350dtex).

  Subsequently, the undrawn yarn was set to a first heating roll 40 ° C., a second heating roll 150 ° C., and a third heating roll 220 ° C., and the draw ratio between the 1-2 heating rolls was 1.824 times, Stretching was performed with a draw ratio between 3 heating rolls of 2.000 times and a relaxation rate between 3rd heating rolls and cold rolls of 0.93 times, and wound at 500 m / min to obtain polyamide 410 fibers ( (Two-stage stretching, stretching ratio 3.648 times).

  In the spinning and drawing processes, thread breakage did not occur and operability was extremely good.

  The properties of the fiber obtained by spinning and drawing are as shown in Table 1. It has very good tensile strength, tensile elongation, boiling water shrinkage, and fineness fluctuation value, and extremely toughness in the knot state. It was good. Furthermore, the wet / wet tensile strength ratio and the strength retention after the dry heat treatment were extremely high, and the change in fiber properties under wet and high temperatures was small.

  When the number of fluffs of the drawn yarn was evaluated, the occurrence of fluff was not observed at all, and the quality of the drawn yarn was extremely excellent.

Example 2
10 parts by weight of nylon 410 salt prepared in Reference Example 1 and 0.304 parts by weight of tetraethylenediamine 10% by weight aqueous solution are placed in a test tube, charged in a pressure vessel and purged with nitrogen, and the pressure in the can is 0.59 MPa with nitrogen. Pressurized. The sealed pressure vessel was set to a heater temperature of 275 ° C. and heating was started. After 3 hours, the internal temperature of the can reached 211 ° C., and the internal pressure of the can reached 1.09 MPa. Subsequently, the heater set temperature was changed to 295 ° C., pressure release was started, and the internal pressure of the can was reduced to zero over 1 hour and 10 minutes while distilling water. At this time, the inside temperature of the can was 258 ° C. Furthermore, by holding for 2 hours 30 minutes under a nitrogen flow, the temperature in the can reached 280 ° C. The pressure vessel was cooled to room temperature, and the solid content was pulverized with a freezer mill to obtain nylon 410 resin (sulfuric acid relative viscosity 2.64).

  This nylon 410 resin was vacuum dried at 105 ° C. for 12 hours (moisture content after drying: 280 ppm), then supplied to a twin screw extruder and melted, and a spinneret (discharge hole diameter 0.23 mm, hole length at a spinning temperature of 285 ° C. 0.30 mm, 12 holes). The spun yarn is cooled by cooling air having a wind temperature of 20 ° C. and a wind speed of 0.6 m / sec, applied with an oil agent by a lubricating device, converged, and taken up by a first godet roll (spinning speed of 600 m / min), It wound up with the winder via the 2nd godet roll rotated at the same speed as the 1st godet roll (undrawn yarn: fineness 145 dtex).

  Subsequently, the unstretched yarn was set to 45 ° C. for the first heating roll and 200 ° C. for the second heating roll, the stretching ratio between the first and second heating rolls was 2.950 times, and between the second heating roll and the cold roll. Stretching was performed at a relaxation rate of 0.98 times, and winding was performed at 600 m / min to obtain polyamide 410 fiber. (One-stage stretching, stretching ratio 2.950 times).

In the spinning and drawing processes, thread breakage did not occur and operability was extremely good.
The properties of the fiber obtained by spinning and drawing are as shown in Table 1. It has very good tensile strength, tensile elongation, boiling water shrinkage, and fineness fluctuation value, and extremely toughness in the knot state. It was good. Furthermore, the wet / wet tensile strength ratio and the strength retention after the dry heat treatment were extremely high, and the change in fiber properties under wet and high temperatures was small.

  When the number of fluffs of the drawn yarn was evaluated, the occurrence of fluff was not observed at all, and the quality of the drawn yarn was extremely excellent.

Example 3
The polyamide 410 resin (sulfuric acid relative viscosity 2.64) obtained in Example 2 was subjected to solid phase polymerization under the conditions of a temperature of 200 ° C. and a pressure of 15 Pa to obtain polyamide 410 having a sulfuric acid relative viscosity of 3.90.

  This polyamide 410 resin was vacuum dried at 105 ° C. for 12 hours (water content after drying 200 ppm), then supplied to a twin screw extruder and melted, and a spinneret (discharge hole diameter 0.3 mm, hole length at a spinning temperature of 295 ° C. 0.75 mm, 18 holes). The spun yarn is cooled by cooling air having a wind temperature of 20 ° C. and a wind speed of 0.7 m / sec, and is converged by applying an oil agent with an oil supply device, and is taken up by a first godet roll (spinning speed of 750 m / min). It wound up with the winder via the 2nd godet roll rotated at the same speed as a 1st godet roller (undrawn yarn: Fineness 350dtex).

  Subsequently, the undrawn yarn was set to a first heating roll 30 ° C., a second heating roll 160 ° C., and a third heating roll 230 ° C., and the draw ratio between the first and second heating rolls was 2.093 times, Stretching was performed with a draw ratio between 3 heating rolls of 2.000 times and a relaxation rate between 3rd heating rolls and cold rolls of 0.94 times, and wound at 500 m / min to obtain polyamide 410 fibers ( (Two-stage stretching, stretch ratio 4.186 times).

  In the spinning and drawing processes, thread breakage did not occur and operability was extremely good.

  The properties of the fibers obtained by spinning and drawing are as shown in Table 1. The tensile elongation is a good value of 17.5%, and the tensile strength, boiling water shrinkage, and fineness variation are extremely good. Had characteristics. The toughness in the nodule state was also good. Furthermore, the wet / wet tensile strength ratio and the strength retention after the dry heat treatment were extremely high, and the change in fiber properties under wet and high temperatures was small.

  When the number of fluffs of the drawn yarn was evaluated, one fluff was generated, but the quality of the drawn yarn was excellent.

Comparative Example 1
8 parts by weight of nylon 410 salt prepared in Reference Example 1 and 0.490 parts by weight of a 10% by weight aqueous solution of tetraethylenediamine are placed in a test tube, charged in a pressure vessel and purged with nitrogen, and then the pressure inside the can is 0.59 MPa with nitrogen. Pressurized. The sealed pressure vessel was set to a heater temperature of 235 ° C. and heating was started. After 6 hours, the internal temperature of the can reached 193 ° C., and the internal pressure of the can reached 1.17 MPa. The pressure vessel was cooled to room temperature, and the obtained solid content was pulverized by a freezer mill to obtain nylon 410 resin (sulfuric acid relative viscosity 1.56).

  This nylon 410 resin was vacuum dried at 105 ° C. for 12 hours (water content after drying: 250 ppm), supplied to a twin screw extruder and melted, and spinneret (discharge hole diameter 0.3 mm, hole length at a spinning temperature of 280 ° C. 0.75 mm, 18 holes). The spun yarn is cooled by cooling air having a wind temperature of 20 ° C. and a wind speed of 0.5 m / second, and is made to converge by applying an oil agent with an oil supply device, and taken up by a first godet roll (spinning speed of 750 m / min). It wound up with the winder via the 2nd godet roll rotated at the same speed as a 1st godet roller (undrawn yarn: Fineness 350dtex).

Subsequently, this undrawn yarn was drawn under the same conditions as in Example 2 to obtain polyamide 410 fibers.
In the spinning process, due to the thermal decomposition of the polyamide 410 resin, the surface of the die was severely soiled and thread breakage occurred twice, and the spinning stability was slightly inferior. In the drawing process, single yarn breakage occurred four times, and the drawability was poor. The destabilization of the spinning process and the drawing process is presumed to be caused by the low relative viscosity of sulfuric acid of the polyamide 410 resin.

  The properties of the fiber obtained by spinning and drawing are as shown in Table 2, and the tensile strength was inferior. When the number of fluffs of the drawn yarn was evaluated, eight fluffs were generated, and the quality of the drawn yarn was extremely poor.

Comparative Example 2
The polyamide 410 resin obtained in Example 2 was subjected to solid phase polymerization under the conditions of a temperature of 200 ° C. and a pressure of 15 Pa to obtain a polyamide 410 resin having a sulfuric acid relative viscosity of 5.20.

  This nylon 410 resin was vacuum-dried at 105 ° C. for 12 hours (moisture content after drying: 210 ppm), then supplied to a twin screw extruder and melted, and a spinneret (discharge hole diameter 0.3 mm, hole length at a spinning temperature of 305 ° C. 0.75 mm, 18 holes). The spun yarn is cooled by cooling air with a wind temperature of 20 ° C. and a wind speed of 0.5 m / second, and is made to converge by applying an oil agent with an oil supply device, and taken up with a first godet roll (spinning speed of 750 m / min). Attempts were made, but the relative viscosity of sulfuric acid of the polyamide 410 resin was so high that the spinnability was low, the yarn breakage occurred frequently, and an undrawn yarn could not be obtained.

Comparative Example 3
The polyamide 410 resin (sulfuric acid relative viscosity 3.90) obtained in Example 3 was vacuum-dried at 105 ° C. for 12 hours (moisture content after drying: 200 ppm), then fed to a twin screw extruder and melted, and a spinning temperature of 295 It was discharged from a spinneret (discharge hole diameter: 0.3 mm, hole length: 0.75 mm, hole number: 18 holes) at 0 ° C. The spun yarn is cooled by cooling air having a wind temperature of 20 ° C. and a wind speed of 0.7 m / sec, applied with an oil agent to be converged, and taken up by a first godet roll (spinning speed of 350 m / min), It wound up with the winder via the 2nd godet roll rotated at the same speed as a 1st godet roller (undrawn yarn: Fineness 620dtex).

  Subsequently, this unstretched yarn was set to a first heating roll 30 ° C., a second heating roll 160 ° C., and a third heating roll 230 ° C., and the draw ratio between the first and second heating rolls was 2.750 times, Stretching was performed with a draw ratio between 3 heating rolls of 2.000 times and a relaxation rate between 3rd heating rolls and cold rolls of 0.94 times, and winding was performed at 200 m / min to obtain polyamide 410 fibers ( (Two-stage stretching, stretch ratio 5.500 times).

  During drawing, single yarn breakage occurred frequently, and it was difficult to perform stable drawing. It is presumed to be due to the high stretch ratio.

  When the number of fluffs of the drawn yarn was evaluated, 15 fluffs were generated, and the quality was extremely poor.

Comparative Example 4
Using the unstretched yarn obtained in Example 1, only the temperature of the third heating roll in Example 1 was changed to perform stretching. That is, the first heating roll 30 ° C., the second heating roll 160 ° C., the third heating roll 245 ° C., the stretching ratio between the 1-2 heating rolls is 2.093 times, and the stretching is between the 2-3 heating rolls. When the stretching was performed with a magnification of 2.000 times and a relaxation rate between the third heating roll and the cold roll being 0.94 times, the single yarns were fused to each other on the third heating roll. Since it was difficult to carry out stable drawing, a drawn yarn could not be obtained.

Reference example 1
Polyamide 66 resin (sulfuric acid relative viscosity 3.80) was vacuum-dried at 105 ° C. for 12 hours, then fed to a twin screw extruder and melted, and spinneret (discharge hole diameter 0.3 mm, hole length 0 at a spinning temperature of 295 ° C. .75 mm, 18 holes). The spun yarn is cooled by cooling air having a wind temperature of 20 ° C. and a wind speed of 0.7 m / sec, and is converged by applying an oil agent with an oil supply device, and is taken up by a first godet roll (spinning speed of 750 m / min). It wound up with the winder via the 2nd godet roll rotated at the same speed as a 1st godet roller (undrawn yarn: Fineness 350dtex).

  Subsequently, the undrawn yarn was set to a first heating roll 40 ° C., a second heating roll 150 ° C., and a third heating roll 220 ° C., and the draw ratio between the 1-2 heating rolls was 1.955 times, Stretching was performed with a draw ratio between 3 heating rolls of 2.000 times and a relaxation rate between 3rd heating rolls and cold rolls of 0.93 times, and wound at 500 m / min to obtain polyamide 66 fibers ( (Two-stage stretching, stretching ratio 3.910 times).

  In the spinning and drawing processes, thread breakage did not occur and operability was extremely good.

  The properties of the fibers obtained by spinning and drawing are as shown in Table 3, and had extremely good tensile strength, tensile elongation, boiling water shrinkage, and fineness fluctuation value, but the toughness in the knot state is inferior. It was a thing.

  Furthermore, the wet / wet tensile strength ratio and the strength retention after the dry heat treatment were inferior, and the fiber property changes under wet and high temperatures were large.

  When the number of fluffs of the drawn yarn was evaluated, the occurrence of fluff was not observed at all, and the quality of the drawn yarn was extremely excellent.

Reference example 2
Polyamide 610 resin (CM2001) manufactured by Toray Industries, Inc. was vacuum-dried at 105 ° C. for 12 hours, then supplied to a twin screw extruder and melted, and a spinneret (discharge hole diameter 0.23 mm, hole length at a spinning temperature of 260 ° C. 0.30 mm, 12 holes). The spun yarn is cooled by cooling air having a wind temperature of 20 ° C. and a wind speed of 0.5 m / sec, applied with an oil agent to be converged, and taken up by a first godet roll (spinning speed of 500 m / min). It wound up with the winder via the 2nd godet roll rotated at the same speed as the 1st godet roll (undrawn yarn: fineness 150dtex).

  Subsequently, the unstretched yarn is set to a first heating roll of 60 ° C. and a second heating roll of 160 ° C., a stretching ratio between the first and second heating rolls is 3.600 times, and between the second heating roll and the cold roll. The relaxation rate was 0.98 times and the film was stretched and wound at 600 m / min to obtain polyamide 610 fiber. (One-stage stretching, stretch ratio 3.600 times).

  In the spinning and drawing processes, thread breakage did not occur and operability was extremely good.

  The properties of the fiber obtained by spinning and drawing are as shown in Table 3, and had very good tensile strength, tensile elongation, boiling water shrinkage, and fineness fluctuation value. Moreover, the toughness drop in the nodule state was also small. In addition, the wet / wet tensile strength ratio was high and the change in fiber physical properties under wet conditions was small, but the strength retention after dry heat treatment was very low, and the change in fiber physical properties at high temperatures was extremely large. there were.

  When the number of fluffs of the drawn yarn was evaluated, the occurrence of fluff was not observed at all, and the quality of the drawn yarn was extremely excellent.

1: Extruder 2: Metering pump 3: Spinning block 4: Spinning pack 5: Spinneret 6: Spinning yarn 7: Cooling device 8: Oil supply device 9: Entangling device 10: First godet roll
11: Second godet roll 12: Winding machine 13: Winding yarn (undrawn yarn)
13: Undrawn yarn 14: Supply roll 15: First heating roll
16: Second heating roll
17: Third heating roll (final heating roll)
18: Final roll (cold roll)
19: drawn yarn pan

Claims (2)

It is a fiber made of a polyamide resin obtained by polycondensation of an aliphatic amine containing tetramethylenediamine as a main component and a carboxylic acid containing sebacic acid as a main component, and satisfies the following formulas (1) to ( 5 ) Polyamide 410 fiber characterized by that.
(1) 3 ≦ tensile strength [cN / dtex] ≦ 10
(2) 15 ≦ tensile elongation [%] ≦ 50
(3) 3 ≦ Boiling water shrinkage [%] ≦ 15
(4) 0.1 ≦ Fineness variation value (U%) [%] ≦ 3.0
(5) The toughness obtained from the tensile strength / elongation value and the toughness obtained from the nodule strength / elongation value are 65 ≦ [(toughness during knot) / (toughness during tension)] × 100 ≦ 100 Polyamide 410 fiber structure characterized by containing a polyamide 410 fibers of claim 1 Symbol placement.

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