Composite false twisted yarn

Abstract

To provide a composite false twisted yarn having soft stretchability causing no binding feeling, high hygroscopic property, and dry touch while stretching according to motion of a body.SOLUTION: A composite false twisted yarn is constituted of a core part and a sheath part and has two-layer structure. The core part is polyamide-based filament and the sheath part is polyester-based filament. Stretch elongation rate of the composite false twisted yarn is 50 to 200%.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a composite false twist textured yarn which, when made into fabric, has soft stretchability that stretches in accordance with body movements without a feeling of restriction, and also has high moisture absorption and a dry feel against the skin. [Background technology]

[0002] Synthetic fibers, such as polyamide and polyester, have many excellent properties, including mechanical properties, and are widely used in various fields, from general clothing applications to industrial applications and functional products. Synthetic fibers are more durable and easier to handle than natural fibers such as cotton and wool, and are therefore suitable for use in sportswear, outdoor clothing, innerwear, and other applications.

[0003] Furthermore, for applications such as sportswear, outdoor jackets, and innerwear, materials must have just the right amount of stretch to expand and contract with the body's movements without feeling restrictive, high moisture absorption to regulate the humidity inside the garment when sweating, and a dry feel that does not cause stress when it comes into contact with the skin.

[0004] Polyamide-based long fibers have higher moisture absorption and mechanical strength than polyester-based long fibers, and therefore are suitable for use in sportswear. However, polyamide-based long fibers have a unique slimy feel when they come into contact with the skin, and this poses a problem in terms of texture.

[0005] To solve this problem, Patent Document 1 proposes a two-layer false-twisted yarn in which a polyamide long fiber with thick and thin spots and high elongation and a thermoplastic synthetic fiber with low elongation are false-twisted simultaneously, so that the polyamide long fiber with thick and thin spots wraps around the thermoplastic synthetic fiber with low elongation so as to cover it. The fine irregularities caused by the thick and thin spots reduce the slimy feeling of the polyamide long fiber and give it a dry feel. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2002-115131 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the two-layer false-twisted yarn of polyamide long fiber described in Patent Document 1, although the slimy feeling is reduced by the unevenness of the surface, it still feels slimier than polyester long fiber and cannot be said to have a dry feel to the skin. In addition, because the false-twisting process is performed using a low-elongation thermoplastic synthetic fiber as the core, it is difficult for the core yarn to become crimped by the false-twisting process, and sufficient stretchability cannot be obtained for sports clothing applications.

[0008] A common method for imparting high stretchability is to combine it with polyurethane-based elastic yarn. However, the stretch of polyurethane-based elastic yarn is very tight, and when made into a fabric and worn, it feels restrictive. In addition, polyurethane-based elastic yarn has issues with light resistance, so it is common to use it after covering it with polyamide-based long fibers or polyester-based long fibers, which leaves issues such as the weight of the product being heavy and the cost of the product being high due to the cost of the covering process.

[0009] The present invention is intended to solve the above-mentioned conventional problems, and provides a composite false twist textured yarn which, when made into fabric, has soft stretchability that stretches in accordance with body movements without a feeling of restriction, and also has high moisture absorption and a dry feel against the skin. [Means for solving the problem]

[0010] In order to solve the above problems, the present invention has the following configuration. (1) A composite false twist textured yarn having a two-layer structure composed of a core yarn and a sheath yarn, the core yarn being a polyamide-based filament and the sheath yarn being a polyester-based filament, and having a stretch elongation rate of 50 to 200%. (2) A composite false twist textured yarn according to (1), in which the polyamide long fiber of the core yarn is a latent crimped yarn having a composite cross section of a side-by-side or eccentric core-sheath type. (3) A composite false twist textured yarn as described in (1) or (2), in which the mass ratio of the polyester long fiber to the polyamide long fiber and the polyester long fiber constituting the composite false twist textured yarn is 50 to 80%. (4) A composite false twist textured yarn as described in (1) or (2), in which the single fiber fineness of the polyamide long fiber core yarn is 1.0 dtex to 5.0 dtex. (5) A composite false twist textured yarn according to (1) or (2), in which the single yarn fineness of the polyester filament of the sheath yarn is 0.5 dtex to 3.0 dtex. (6) A composite false twist textured yarn according to (1) or (2), having a degree of entanglement of 150 to 350. Effect of the Invention

[0011] According to the present invention, it is possible to provide a composite false twist textured yarn which, when made into fabric, has soft stretchability that stretches in accordance with body movements without a feeling of restriction, and also has high moisture absorption and a dry feel against the skin. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram showing an example of a composite cross section of a polyamide-based long fiber core yarn in the present invention. [Diagram 2] Schematic side view of composite false twist textured yarn of the present invention. [Diagram 3] Image diagram of the composite false twist textured yarn of the present invention when tension is applied in the yarn longitudinal direction [Figure 4] Schematic diagram of a composite false twist texturing device according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described in detail. The present invention relates to a composite false twist textured yarn having a polyamide long fiber as a core yarn and a polyester long fiber as a sheath yarn. Polyamides may be any polyamide produced by repeated condensation polymerization of amide bonds, such as nylon 6, nylon 66, nylon 12, and nylon 610, and may also contain a small amount of a third component. Polyamides have hydrophilic amide groups in the main chain of the molecule, making them a material with relatively excellent moisture absorption properties among synthetic fibers. Moisture absorption varies depending on the type of polyamide and fiber modification, but the ΔMR of preferred polyamide long fibers is 2.0 or more.

[0014] The core yarn constituting the composite false twist textured yarn of the present invention is not particularly limited as long as it is a polyamide-based long fiber. From the viewpoint of soft stretchability, it is preferably a polyamide-based latent crimped yarn. Examples of polyamide-based latent crimped yarn include polyamide-polyamide composite cross section fiber, polyamide-polyurethane composite cross section fiber, and polyamide-polyester composite cross section fiber. It is preferably a polyamide-polyamide composite cross section fiber, which is a composite cross section fiber in which two types of polyamide components are composited in a laminated or eccentric core-sheath type in the fiber cross section. By using a latent crimped yarn, a three-dimensional coil crimp (latent crimp) is imparted, resulting in good soft stretchability.

[0015] More preferably, the eccentric sheath-core composite cross section fiber has a core component A of nylon 610 or nylon 612 and a sheath component B of nylon 6, which can exhibit excellent soft stretchability, texture, and durability. FIG. 1 is a schematic diagram illustrating the cross section of an eccentric sheath-core composite cross section fiber. Furthermore, the interface of the laminated composite cross section fiber may be straight or curved, and is not limited, as long as it does not impair the effects of the present invention. The composite ratio is preferably component A:component B=2:1 to 1:2 (area ratio).

[0016] Polyester is a material with excellent quick-drying properties, and the sheath yarn of the composite false twist textured yarn of the present invention is made of polyester long fibers, which provide a dry feel to the skin, a smooth feel to the skin, and a refreshing feel to the touch.

[0017] The polyester is preferably polyethylene terephthalate (PET) in which 80 mol % or more of the repeating units are ethylene terephthalate, polybutylene terephthalate (PBT) in which 80 mol % or more of the repeating units are butylene terephthalate, or polytrimethylene terephthalate (PTT) in which 80 mol % or more of the repeating units are trimethylene terephthalate.

[0018] In addition, as a third component, aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalene 2,6-dicarboxylic acid, phthalic acid, and 5-sodium sulfoisophthalic acid, and aliphatic dicarboxylic acids such as adipic acid and sebacic acid may be copolymerized to an extent that does not impair the fiber-forming properties of the homopolymer.

[0019] A preferred polyester-based filament is a cationic dyeable PET filament, the third component of which is an isophthalic acid component containing a metal sulfonate group, and the content of the third component is 0.8 mol% to 2.5 mol%. In recent years, fashionable sports and outdoor clothing has become mainstream, and materials with good color development have become mainstream, so cationic dyeable PET filament is preferred, which can provide high color development. In addition, washing fastness is required for innerwear applications, and it can be dyed with cationic dyes that are compatible with polyamide dyeing, and a composite false twist textured yarn with good washing fastness can be obtained.

[0020] In addition, as environmental issues have been attracting attention, plant-derived biopolymers and recycled polymers are also suitable for the present invention in terms of reducing the environmental load. The polyester polymer and polyamide polymer in the present invention may be recycled polymers that have been recycled by any of chemical recycling, material recycling, and thermal recycling.

[0021] The composite false twist textured yarn of the present invention has a stretch extension rate of 50% to 200%, preferably 70% to 120%. By setting the stretch extension rate to 50% to 200%, when the fabric is made, it is possible to obtain soft stretchability without a feeling of restriction while stretching in accordance with the movement of the body. When the stretch extension rate is less than 50%, when the fabric is made, the soft stretchability is insufficient. The higher the stretch extension rate, the better the stretchability, but when the stretch extension rate exceeds 200%, processing wrinkles are likely to occur when the fabric is made into a woven or knitted fabric. In order to suppress the wrinkles, the fabric is heat-set under high tension in the warp direction, which results in a loss of stretchability of the woven or knitted fabric.

[0022] The composite false twist textured yarn of the present invention, as shown in FIG. 2, has a two-layer structure in which a polyester long fiber sheath yarn is wrapped around a polyamide long fiber core yarn. By winding more of the sheath yarn around the core yarn, the area of ​​the core yarn that is covered by the sheath yarn increases, and when the fabric is made, the area of ​​the polyamide long fiber core yarn that comes into contact with the skin is reduced, resulting in the dry feel of polyester long fiber.

[0023] Furthermore, the shrinkage caused by false twisting enters the core yarn and the sheath yarn, creating a gap between them, which further reduces the area of ​​the polyamide filament of the core yarn that comes into contact with the skin when made into a fabric, providing a dry feel to the skin. In addition, the shrinkage caused by false twisting also provides soft stretchability.

[0024] In addition, by winding more of the sheath yarn around the core yarn, the sheath yarn becomes longer than the core yarn. When the core yarn has more crimp than the sheath yarn, if the difference in yarn length between the sheath yarn and the core yarn is not sufficient, when tension is applied to the composite false twisted yarn in the yarn longitudinal direction, the sheath yarn will stretch before the crimp of the core yarn stretches to its full extent, and soft stretchability will not be achieved. By winding more of the sheath yarn around the core yarn and increasing the difference in yarn length between the sheath yarn and the core yarn, the composite false twisted yarn can also stretch until the crimp of the core yarn stretches to its full extent, as shown in Figure 3, and soft stretchability can be achieved.

[0025] The degree of entanglement of the composite false twist textured yarn of the present invention is preferably 150 to 350. The entangled portion is a state in which the yarns are entangled and converged. The entanglement of the yarns restricts the stretching of the yarn. The more entangled portions there are, the lower the soft stretchability of the yarn. In particular, when the core yarn has more crimp than the sheath yarn, the sheath yarn becomes entangled with the core yarn due to entanglement, which inhibits the stretching of the core yarn and reduces the soft stretchability. By setting the degree of entanglement to 350 or less, the sheath yarn and core yarn are less entangled, and soft stretchability is obtained. By setting the degree of entanglement to 150 or more, the sheath yarn and core yarn do not come apart, and good processability is obtained.

[0026] Of the polyamide long fiber and polyester long fiber constituting the composite false twist textured yarn of the present invention, the mass ratio of the polyester long fiber is preferably 50% to 80%, more preferably 50% to 75%. By making the mass ratio of the polyester long fiber in the sheath yarn 50% or more, the polyester long fiber sufficiently covers the polyamide long fiber, and when the fabric is made, the polyester long fiber comes into contact with the skin, giving a dry feel. By making the mass ratio of the polyester long fiber in the sheath yarn 80% or less, sufficient moisture absorption is obtained when the fabric is made.

[0027] The single yarn fineness of the polyamide long fiber core yarn is preferably 1.0 dtex to 5.0 dtex. By making the single yarn fineness of the core yarn 1.0 dtex or more, even if the processing temperature and draw ratio during the composite false twist processing are set high and a lot of false twist crimp is introduced, there is little single yarn breakage and good soft stretchability is obtained. By making the single yarn fineness of the core yarn 5.0 dtex or less, the stiffness and stiffness of the core yarn are reduced, resulting in a soft texture.

[0028] The single yarn fineness of the polyester long fiber sheath yarn is preferably 0.5 dtex to 3.0 dtex. By setting the single yarn fineness of the sheath yarn to 0.5 dtex or more, even if the processing temperature and the draw ratio during the composite false twist processing are set high and many false twist crimps are introduced, single yarn breakage is reduced and good soft stretchability is obtained. By setting the single yarn fineness of the sheath yarn to 3.0 dtex or less, the sheath yarn can easily cover the core yarn uniformly, which enhances the smooth texture of the polyester long fiber and provides a dry feel to the skin.

[0029] The total fineness of the composite false twist textured yarn of the present invention is preferably 20 dtex to 200 dtex, taking into consideration its use in clothing.

[0030] An example of the method for producing the composite false twist textured yarn of the present invention will now be described in detail. The composite false twist textured yarn of the present invention is produced by obtaining partially oriented undrawn yarns of polyamide long fibers and polyester long fibers by a known melt spinning method, and then using each partially oriented undrawn yarn, a composite false twist textured yarn is produced by a known composite false twist texture method.

[0031] The melt spinning method for polyamide-polyamide composite cross section fiber as the polyamide-based continuous fiber that is the core yarn of the composite false twist textured yarn of the present invention will be exemplified. The melt spinning method is similar for polyamide single component fiber.

[0032] Two types of polyamides, A and B, with different viscosities, are arranged in a laminated or eccentric core-sheath arrangement and spun. The melt viscosity ratio of the polyamides A and B is preferably 0.3 to 3.0, more preferably 0.5 to 2.0. By setting the ratio in this range, a shrinkage difference appears between the polyamides A and B, and the coil crimpability is increased, resulting in good soft stretchability. In addition, the yarn discharged from the spinneret does not bend, and spinning stability is good. In the polyamide-based long fiber of the core yarn of the composite false twist textured yarn of the present invention, the shape of the interface between the A and B components is not particularly limited. In addition, the composite ratio of the A and B components is preferably A:B=2:1 to 1:2 (area ratio).

[0033] Next, an example of the manufacturing process will be described. Polyamide component A and polyamide component B are melted separately at a temperature 20°C to 60°C higher than their melting points and extruded from a laminated or eccentric core-sheath type composite spinneret. The extruded yarn is uniformly cooled to room temperature by a cooling device installed downstream of the spinneret, and then an oil is applied in an oiling device, entangled in an entanglement device, and a second oil is applied in an oiling device. The yarn is then passed through a take-up roller and a stretching roller and wound up on a winding device.

[0034] At this time, the peripheral speed of the take-up roller (hereinafter referred to as the take-up speed) is preferably 2500 m / min to 4500 m / min. By setting the take-up speed to 2500 m / min or more, the wound package does not swell, and the form collapses, the loop is removed, and the winding is less likely to occur. By setting the take-up speed to 4500 m / min or less, many unoriented parts of the partially oriented undrawn yarn remain, which is preferable because crystallization in the twisted state during false twist processing tends to progress and crimping tends to occur. In addition, it is preferable to draw at 1.0 times to 1.1 times according to the ratio of the peripheral speeds of the take-up roller and the drawing roller.

[0035] The polyamide long fiber core yarn of the composite false twist textured yarn of the present invention exhibits two types of crimp after composite false twist processing: coil crimp (latent crimp) and false twist crimp (manifest crimp). In order to make both types of crimp dense and uniform, it is preferable to reduce the degree of entanglement of the polyamide long fiber core yarn before crimping occurs, within the range that does not cause yarn unraveling.

[0036] In the manufacturing method of the present invention, it is preferable to carry out oiling for the purpose of adding moisture before the entanglement treatment, and then carry out two-stage oiling for the purpose of adding oil after the entanglement treatment. By adopting such a manufacturing process, there are fewer entanglement points, and the filaments converge in an untangled state.

[0037] The oil applied before the interlacing treatment is preferably a water-containing oil. The amount of the water-containing oil applied before the interlacing treatment is preferably 5% by weight to 15% by weight based on the amount of polymer passing through. The amount of moisture applied is adjusted by the amount of polymer discharged, the oil concentration, and the amount of oil applied. For oiling after the interlacing treatment, a known oil suitable for false twisting is used.

[0038] The entanglement pressure is preferably 0.1 MPa to 0.3 MPa. By setting the entanglement pressure to 0.1 MPa or more, entanglement can be imparted and yarn loosening can be suppressed, and by setting the pressure to 0.3 MPa or less, the degree of entanglement can be reduced.

[0039] The polyester-based continuous fiber used as the sheath yarn of the composite false twist textured yarn of the present invention is exemplified by a method for melt spinning cationic dyeable PET continuous fiber.

[0040] The polyester is melted at a temperature 20°C to 60°C higher than its melting point, metered and transported by a gear pump, and discharged from a spinneret. The discharged yarn is uniformly cooled to room temperature by a cooling device installed downstream of the spinneret, and then oiled by an oiling device. The yarn is then taken up by a take-up roller at a specified peripheral speed and a winding device.

[0041] The take-up speed is preferably 2000 m / min to 3500 m / min. By setting the take-up speed to 2000 m / min or more, the orientation is stabilized, the orientation variation in the yarn length direction is reduced, and uniform yarn quality is obtained. By setting the take-up speed to 3500 m / min or less, many unoriented portions remain in the obtained yarn, which makes it easier for crystallization to proceed in the twisted state during false twist processing, and makes it easier for fine crimps to occur.

[0042] An appropriate cooling method is selected depending on the polymer, single fiber fineness, and cross-sectional shape, but when making cationic dyeable PET filament finer, it is preferable to uniformly cool the filament over an appropriate cooling start distance using a circular cooling device because the cooling and solidification point after discharge from the spinneret is short.

[0043] In the production of the composite false twist textured yarn of the present invention, the difference in breaking elongation between the polyamide-based partially oriented undrawn yarn used for the core yarn and the polyester-based partially oriented undrawn yarn used for the sheath yarn is preferably 70 to 300%. By false twisting partially oriented undrawn yarns with different breaking elongations, the yarn on the higher elongation side is wound around the yarn on the lower elongation side and drawn with a yarn length difference, resulting in a composite false twist textured yarn with a two-layer structure composed of the core yarn and the sheath yarn. The greater the difference in breaking elongation between the partially oriented undrawn yarns used for the core yarn and the sheath yarn, the more the sheath yarn is wound around the core yarn, and when the fabric is made, the area of ​​the polyamide-based long fiber of the core yarn that touches the skin is reduced, resulting in a dry feel.

[0044] In addition, by winding the sheath yarn around the core yarn more, the yarn length of the sheath yarn becomes longer than that of the core yarn. When the crimp of the core yarn is more than that of the sheath yarn, if the yarn length difference between the sheath yarn and the core yarn is insufficient, when tension is applied to the composite false twisted yarn in the yarn longitudinal direction, the sheath yarn will fully stretch before the crimp of the core yarn is fully stretched, and soft stretchability will not be obtained. By winding the sheath yarn around the core yarn more and increasing the yarn length difference between the sheath yarn and the core yarn, the composite false twisted yarn can also stretch until the crimp of the core yarn is fully stretched, as shown in Figure 3, and soft stretchability is obtained. Therefore, from the viewpoint of soft stretchability, it is better to have a large difference in breaking elongation between the partially oriented undrawn yarn used for the core yarn and the sheath yarn. Although it depends on the constituent polymers and false twisting conditions, it is preferable that the difference in breaking elongation is 70% or more. On the other hand, if the difference in breaking elongation is more than 300%, many yarn breaks occur during composite false twist texturing, resulting in low productivity. Therefore, it is appropriate that the difference in breaking elongation is 300% or less.

[0045] Next, a preferred false twisting method will be described. The composite false twist textured yarn of the present invention can be obtained by a conventionally known composite false twist texture technique, and preferably, false twist texture is applied using a draw-friction false twist texture device. As an example of a draw-friction false-twisting method, as shown in Fig. 4, two partially oriented undrawn yarns (a, b) supplied to a draw-friction false-twisting device are sent to a first feed roller e via a zeroth feed roller c and an interlace nozzle d. The yarn is then guided to a second feed roller i through a heated first heater f, a cooling plate g, and a twisting body h that performs draw-friction false-twisting, and wound up as a false-twisted yarn. As for the draw-friction false-twisting, the yarn may be subjected to drawing using a hot pin or a hot plate before the zeroth feed roller, and then subjected to friction false-twisting.

[0046] The core yarn and the sheath yarn are entangled with air by an interlace nozzle between the 0th feed roller and the 1st feed roller. The compressed air pressure is preferably 0.05 MPa to 1.0 MPa, more preferably 0.1 MPa to 0.5 MPa. If it is less than 0.05 MPa, the yarn will not be mixed sufficiently, and if it exceeds 1.0 MPa, the yarn will be rubbed and fuzzed. In addition, the yarn is overfed and fed due to the speed difference between the 0th feed roller and the 1st feed roller, thereby reducing the tension of the yarn entering the interlace nozzle and making it easier to entangle the yarn. The overfeed rate is preferably 0.0 to 5.0%, more preferably 0.1 to 1.0%. If the overfeed rate is increased, entanglement will be achieved even with a low compressed air pressure, thereby saving the amount of air. If the overfeed rate is increased above 5.0%, the occurrence of loops and slack will increase. If the overfeed rate is too high, the variation in the degree of entanglement in the longitudinal direction of the yarn will increase. The ease of entanglement varies depending on the fineness composition and the type of polymer, but is adjusted appropriately to obtain the required degree of entanglement.

[0047] The heating method includes high-temperature contact heaters and high-temperature non-contact heaters, but is not limited thereto. It is necessary to apply heat firmly to the yarn with a high-temperature contact heater to rearrange the molecules in the fiber and relieve the distortion in order to obtain high shrink performance. Therefore, a high-temperature contact heater is preferable, and its processing temperature (heater setting temperature with a contact hot plate) is preferably 160°C to 190°C. Both contact and non-contact heaters can be used as heater heating methods. In order to impart shrinkage, it is preferable that the temperature of the yarn passing through the inside of the heater is above the crystallization temperature and below the melting point of the polymer used, and for polyester and polyamide, the contact heater temperature is preferably in the range of 160°C to 190°C. A high heater temperature increases the shrinkage rate, but since the sheath yarn is not under tension and polymer fusion due to heat is likely to occur, a temperature of 190°C or less is preferable. The behavior differs depending on the heating method, processing speed, and total fineness of the yarn, so it is adjusted appropriately to obtain the desired shrinkage (shrinkage rate).

[0048] The twisting body is not limited to a pin type, a friction type, a belt nip type, etc. When it is desired to strengthen the crimp, it is preferable to use a pin type, and when it is desired to increase the processing speed and reduce the production cost, it is preferable to use a friction type or a belt nip type. In the present invention, in order to obtain a composite false twist yarn with a two-layer structure in which the sheath yarn is wound around the core yarn, the friction type is preferably used. The material, diameter (40 to 60 mm), number (4 to 12), interval (0.4 to 0.6 mm), and rotation speed of the friction disk are appropriately adjusted to obtain the desired crimp (crimp rate).

[0049] It is preferable that the false twist coefficient K is 1500≦K≦4000. By setting the false twist number K to 1500 or more, sufficient crimp can be imparted while winding the sheath yarn around the core yarn. Also, a high false twist number K is preferable because it allows more crimp to be imparted and more sheath yarn to be wound around the core yarn. However, even if the false twist number K is set to more than 4000, the number of crimps will not change and yarn breakage will become more likely, so a false twist number K of 4000 or less is preferable. However, false twist coefficient K = false twist number T × (total fineness) 1 / 2(Number of false twists T: Number of twists per meter in twisted state (turns / m)) The processing speed is preferably in the range of 300 m / min to 650 m / min. When the yarn is produced in this range, yarn breakage does not occur frequently, and the yarn can be produced at a high yield. More preferably, the processing speed is set to 300 m / min to 450 m / min, which extends the time the yarn passes through the heater in a twisted state, and improves the heat setting property of the crimp.

[0050] The draw ratio needs to be optimized depending on the spinning conditions and processing conditions, but a range of 1.1 to 1.7 times is appropriate. By setting it to 1.1 times or more, it is possible to stably add twist to the yarn. In addition, by drawing at 1.1 times or more, a difference in yarn length occurs between the core yarn and the sheath yarn, resulting in a core-sheath structure. By setting it to 1.7 times or less, it is possible to obtain yarn that is free of yarn breakage and fluff. However, the draw ratio should be appropriately adjusted depending on the elongation of the partially oriented undrawn yarn used.

[0051] In the case of single-yarn false twisting, it is common to pass the yarn through an interlace nozzle between the third feed roller j and the fourth feed roller k after drawing to impart entanglement in order to improve unwinding properties, but the composite false twisted yarn of the present invention is sufficiently entangled before drawing, so entanglement after drawing is not necessary. Even if the filaments are passed through an interlace nozzle after drawing, they do not open up, but simply rotate inside the interlace nozzle, which can cause yarn breakage due to abrasion.

[0052] Before the composite false twist textured yarn is wound into a package n by a drive roller m, it is preferable to bring the yarn into contact with an oiling roller l and apply an oil to the yarn, which improves the unwinding property and improves the processability during knitting and weaving. EXAMPLES

[0053] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. The measurement methods of the property values ​​in the examples are as follows.

[0054] Telescopic elongation rate The stretching and elongation rates were measured according to JIS L 1013 (Method C) (2010 edition), except that the heat treatment method was to treat the material in hot water at a temperature of 90°C for 20 minutes without applying a load.

[0055] Crimp rate CR The composite false twist textured yarn is wound 10 times on a measuring machine with a circumference of 1.0 m, and then the skein is taken. An initial load of 0.002 x number of turns x 2 / 1.111g is applied to this skein. Hot water treatment at 90℃ for 20 minutes, Leave it for at least 12 hours after dehydration. After being left standing, a measurement load of fineness×0.1×winding number×2 / 1.111 g is applied to the skein in addition to the initial load, and the skein is then dangled in water and left for 2 minutes. Measure the length of the spool that has been left as it is and call it L. Then, remove the measurement load and leave it for 3 minutes with only the initial load applied, measure the length of the spool and call it L1. Calculate the crimp rate CR from the following formula. Crimp rate (%)=(L-L1) / L×100 Intertwining degree The spread length (mm) was measured under the following conditions using an automatic entanglement tester (Entanglement Tester R-2040 manufactured by Rothschild) with performance equivalent to that described in JIS L 1013 (2010). The spread length is the distance from the needle point of the measured yarn to the point where the trip level tension is reached and tripped. [Setting conditions] Yarn feeding tension: 0.09 (g / dtex) Trip level tension: 0.18 / filament number + feed tension (g / dtex) The spread length was measured 50 times, and the average spread length was calculated. The degree of entanglement was calculated from the average spread length using the following formula. Degree of entanglement = 1000 / average opening length.

[0056] Single yarn size The composite false twist textured yarn is wound 100 times at a yarn feed tension of 0.09 (g / dtex) on a measuring machine with a frame circumference of 1.0 m to create a skein. The weight of the skein is measured and multiplied by 100, and the result is divided by the filament number of the false twist textured yarn to obtain the single yarn fineness.

[0057] Soft and stretchy The manufactured composite false twist textured yarn was supplied as warp and weft to weave a plain weave (warp and weft density 70 threads / 2.54 cm), with a basis weight of 30 g / cm 2 The resulting fabric was scoured by a conventional method, dried in a cylinder dryer at 120°C, and then pre-set at 170°C. It was then cationic dyed under the following conditions to obtain a fabric with a warp and weft density of 75 threads / 2.54 cm. The elongation of the obtained woven fabric was measured according to the constant speed elongation method (Method A) of JIS L1096 (2010). Using a tensile tester, a woven fabric sample with a width of 5 mm and a width of 300 mm was stretched to 14.7 N in the warp direction of the fabric at a tensile speed of 200 mm / min with a gripping distance of 200 mm, and the elongation was measured. The soft stretchability was evaluated on a three-level scale. A (Good): 20% or more B (Acceptable): 15% or more but less than 20% C (unacceptable): Less than 15% [Dyeing conditions] Dye: Eisen Carotene Blue GLH 0.7wt% Dyeing Aid 1: Sodium acetate 0.15g / L Dyeing Aid 2: Acetic acid 0.5mL / L Dyeing temperature: 98℃ x 20 minutes.

[0058] Moisture absorption and release (ΔMR) The manufactured composite false twist textured yarn is cut into skeins using a measuring machine, and a sample of about 1 to 2 g is placed in a weighing bottle. It is kept at 110°C for 2 hours to dry and the weight is measured (W0). Next, the target substance is kept at 20°C and a relative humidity of 65% for 24 hours, after which the weight is measured (W65). This is then kept at 30°C and a relative humidity of 90% for 24 hours, after which the weight is measured (W90). The calculation was then performed according to the following formula. MR1 = [(W65-W0) / W0] x 100% MR2 = [(W90-W0) / W0] x 100% ΔMR = MR2 - MR1 A ΔMR of 0.3 or more was considered to be acceptable.

[0059] Dry feeling As described above in the "Soft stretchability" section, the manufactured composite false twist textured yarn was supplied as warp and weft yarns to weave a plain weave, and a cationic dyed woven fabric was obtained. The resulting woven fabric was evaluated for texture by 10 experienced inspectors. The fabric made from composite false twist textured yarn (Comparative Example 2) in which the core yarn and sheath yarn are polyamide long fibers was used as the standard, and the dry feel was evaluated on the following three-point scale. A total of 21 points or more was considered to pass. 3 points: Very good 2 points: Good 1 point: Equivalent.

[0060] Example 1 A partially oriented undrawn composite polyamide yarn for the core was prepared by the following method. Nylon 6 (relative viscosity ηr: 3.3, melting point 222°C, no titanium oxide) was used as polyamide component A, and nylon 610 (relative viscosity ηr: 2.7, melting point 225°C) was used as polyamide component B. Component A chips and component B chips were melted at 290°C and 270°C, respectively, using a pressure melter, and melt-extruded at a component A / component B composite ratio of 50 / 50 using an eccentric core-sheath type composite spinneret (10 holes) (spinning temperature 285°C). The yarn discharged from the spinneret was cooled and solidified in a yarn cooling device, an aqueous oil was added to the yarn by an oiling device, the yarn was passed through a fluid entangling nozzle device and entangled at an entangling air pressure of 0.15 MPa, an oil for false twist processing was then added by an oiling device, the yarn was taken up by an unheated take-up roller, and after being stretched to 1.07 times between heated stretching rollers, it was wound onto a package at a take-up speed of 4200 m / min to obtain a partially oriented undrawn yarn of composite polyamide having 31 dtex 10 filaments, an elongation of 75%, and a stretch elongation rate of 18%.

[0061] A partially oriented undrawn polyester sheath yarn was prepared by the following method. Cationic dyeable PET containing 1.6 mol% of an isophthalic acid component containing a metal sulfonate group was melted at 284°C in a single-screw extrusion kneader and melt extruded at 285°C using a die with 96 holes. The yarn extruded from the die was cooled and solidified in a yarn cooling device, divided into two 48 filament yarns, and oiled with a high-friction oil agent for false twisting using an upper oiling device. The yarn was wound around a drum at a winding speed of 2000 m / min to obtain a cationic dyeable polyester partially oriented undrawn yarn with 65 dtex, 48 filaments, and an elongation of 210%.

[0062] Next, the composite false twist texturing method will be described. A composite false twisting process was carried out using a three-axis friction type friction disk type stretch friction false twisting machine. The obtained composite polyamide partially oriented unstretched yarn and cationic dyeable polyester partially oriented unstretched yarn were simultaneously fed to the 0th feed roller and fed to the 1st feed roller through an interlace nozzle. The overfeed rate of the 0th feed roller was 1.0%, and the interlace nozzle interlace pressure was 0.25 MPa. The stretch ratio due to the speed difference between the 1st feed roller and the 2nd feed roller was 1.35 times, and the false twist heater temperature was 180 ° C. Stretch false twisting was carried out with a urethane disk diameter of 51 mm, 9 disks, and a disk distance of 0.4 mm, with a false twist number of 25,000, and a false twist oil was applied and wound on a paper tube. The obtained composite false twist textured yarn was 77 dtex 58 filament, and had good properties as shown in Table 1.

[0063] [Table 1]

[0064] Example 2 A composite false twist textured yarn was obtained in the same manner as in Example 1, except that the spinneret used to spin the composite polyamide partially oriented undrawn yarn for the core yarn was changed to 31 dtex, 20 filaments. As shown in Table 1, the composite false twist textured yarn obtained had good properties.

[0065] Example 3 A composite false twist textured yarn was obtained in the same manner as in Example 1, except that the spinneret used to spin the composite polyamide partially oriented undrawn yarn for the core yarn was changed to 31 dtex 6 filaments. As shown in Table 1, the obtained composite false twist textured yarn had good properties.

[0066] Example 4 A composite false twist textured yarn was obtained in the same manner as in Example 1, except that the spinneret used to spin the polyester partially oriented undrawn yarn for the sheath yarn was changed to 84 dtex 72 filaments. As shown in Table 1, the composite false twist textured yarn obtained had good properties.

[0067] Example 5 A composite false twist textured yarn was obtained in the same manner as in Example 1, except that the spinneret used for spinning the polyester partially oriented undrawn yarn for the sheath yarn was changed to 33 dtex, 24 filaments. As shown in Table 1, the composite false twist textured yarn obtained had good properties.

[0068] Example 6 A composite false twist textured yarn was obtained in the same manner as in Example 1, except that the spinneret used for spinning the polyester partially oriented undrawn yarn for the sheath yarn was changed to 66 dtex 18 filaments. As shown in Table 1, the composite false twist textured yarn obtained had good properties.

[0069] Example 7 A composite false twist textured yarn was obtained by processing in the same manner as in Example 1 using a partially oriented undrawn yarn obtained by the same method as in Example 1, except that the entanglement air pressure was set to 0.1 MPa. The obtained composite false twist textured yarn had good properties as shown in Table 1.

[0070] Example 8 A composite false twist textured yarn was obtained by processing in the same manner as in Example 1 using a partially oriented undrawn yarn obtained by the same method as in Example 1, except that the entanglement air pressure was set to 0.5 MPa. As shown in Table 1, the obtained composite false twist textured yarn had good properties.

[0071] Example 9 Except for using a single-component PET sheath yarn that did not contain an isophthalic acid component, a composite false twist textured yarn was obtained in the same manner as in Example 1. As shown in Table 1, the obtained composite false twist textured yarn had good properties.

[0072] Comparative Example 1 The core yarn was made by combining polytrimethylene terephthalate and polyethylene terephthalate in a side-by-side type in a combination ratio (weight ratio) of 5:5, and the composite was spun at a spinning speed of 5,000 m / min to obtain a highly oriented undrawn yarn of 33 dtex, 12 filaments, and an elongation of 20%. The sheath yarn was a cationic dyeable polyester partially oriented undrawn yarn having 65 dtex, 48 filaments, and an elongation of 210%, obtained in the same manner as in Example 1. A composite false twist textured yarn was obtained by composite false twist texturing in the same manner as in Example 1, except that the draw ratio during composite false twist texturing was 1.10 and the false twist heater temperature was 160° C. As shown in Table 2, the obtained composite false twist textured yarn had good soft stretchability and dry feel, but did not have moisture absorption.

[0073] Comparative Example 2 The core yarn was prepared in the same manner as in Example 1 to obtain a partially oriented undrawn yarn of a composite polyamide having 31 dtex, 10 filaments, and an elongation of 75%. The sheath yarn was a polyamide partially oriented undrawn yarn having a 70 dtex, 48 filament and an elongation of 60% obtained by spinning nylon 6 at 4,500 m / min. A composite false twist textured yarn was obtained by composite false twist texturing in the same manner as in Example 1. The composite false twist textured yarn obtained had high moisture absorption but did not have sufficient stretchability, resulting in a fabric with a strong slimy feel.

[0074] Comparative Example 3 A composite false twist textured yarn was obtained by processing in the same manner as in Example 1 using a partially oriented undrawn yarn obtained by the same method as in Example 1, except that the false twist heater temperature was set to 130° C. The composite false twist textured yarn obtained had high moisture absorption and a good dry feel, but lacked soft stretchability.

[0075] [Table 2] [Explanation of symbols]

[0076] 1: Polyamide A component 2: Polyamide B component A: Core thread B: Sheath thread a: Partially oriented undrawn yarn for core yarn b: Partially oriented undrawn yarn for sheath yarn c: No. 0 feed roller d: Interlace nozzle e: 1st feed roller f: 1st heater g:Cooling plate h: Twisted body i: Second feed roller j: 3rd feed roller k: 4th feed roller l: Oiling roller m: Drive roller n:Package

Claims

1. The composite false twist textured yarn has a two-layer structure composed of a core yarn and a sheath yarn, the core yarn being a polyamide-based long fiber and the sheath yarn being a polyester-based long fiber, and has a stretch elongation rate of 50% to 200%.

2. 2. A composite false twist textured yarn according to claim 1, wherein the polyamide long fiber core yarn is a latent crimped yarn having a composite cross section of a side-by-side or eccentric core-sheath type.

3. 3. The composite false twist textured yarn according to claim 1, wherein the mass ratio of the polyester long fibers to the polyamide long fibers and the polyester long fibers constituting the composite false twist textured yarn is 50% to 80%.

4. 3. The composite false twist textured yarn according to claim 1, wherein the single filament fineness of the polyamide long fiber core yarn is 1.0 dtex to 5.0 dtex.

5. 3. The composite false twist textured yarn according to claim 1, wherein the polyester filament sheath yarn has a single filament fineness of 0.5 dtex to 3.0 dtex.

6. 3. The composite false twist textured yarn according to claim 1 or 2, wherein the degree of entanglement is 150 to 350.

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