Polyester combined interlaced yarn

Abstract

To provide a polyester combined interlaced yarn allowing acquisition of a woven or knitted fabric having sufficient bulged and bulky feeling and excellent deep dyeing property.SOLUTION: A polyester combined interlace yarn is an interlaced yarn formed of a polyester yarn A and a polyester yarn B, includes 50 mass% or more of the polyester yarn A in the interlaced yarn, and satisfies following (1) and (2): (1) having 25 to 90 pieces of fiber-opening part X, which is 5.5 to 8.5 mm in length in a yarn longitudinal direction and 0.4 to 0.8 mm in height, per 1 m of yarn; (2) having 200 to 300 pieces of bulky part Z, which is 2 to 4 mm in length in the yarn longitudinal direction and 0.5 to 2.5 mm in height, per 1 m of yarn after being subjected to heat treatment at 130°C for 30 minutes.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a mixed-fiber entangled polyester yarn which is an entangled yarn made of two types of polyester yarns and has open portions in the longitudinal direction of the yarn. [Background technology]

[0002] With the recent trend toward luxury in the field of women's clothing (particularly in the field of formal black), there is a demand for textured yarns that have excellent deep dyeability when made into woven or knitted fabrics. In response to this demand, many textured yarns have been investigated, and the use of polyester filament yarns as textured yarns has been widely investigated.

[0003] Patent Document 1 describes that by interlacing polyester crimped yarn having an uneven surface or micropores with non-crimped drawn yarn using a Taslan nozzle, a polyester composite bulky textured yarn can be obtained that exhibits excellent deep dyeing effects and moderate volume.

[0004] Patent Document 2 describes a method for producing a woven fabric (polyester formal wear) with a deep dyeing effect, using a mixed-fiber entangled multifilament yarn obtained by interlacing a false-twisted polyester multifilament yarn, the cross section of which is gear-shaped when part of it is dissolved in alkali, and a side-by-side polyester multifilament yarn of a copolymer polyester and a homopolyester under specific conditions using an interlace nozzle.

[0005] However, the mixed entangled yarn of Patent Document 1 is entangled using a Taslan nozzle, and therefore, loop fluff and slack are formed throughout the yarn. When the mixed entangled yarn is heat-treated, the crimped yarn and the non-crimped yarn are in a disordered state throughout the yarn, and both types of yarn are mixed on the surface of the yarn. As a result, the woven or knitted fabric obtained by dyeing has insufficient deep dyeability.

[0006] Furthermore, in Patent Document 2, the side-by-side polyester multifilament yarn has a smaller hot water shrinkage rate than a high-shrinkage yarn, and therefore the shrinkage after heat treatment is not sufficiently large. Therefore, in the mixed-fiber entangled multifilament yarn after heat treatment, the false-twisted polyester multifilament yarn unevenly distributed in the sheath portion is not raised to the yarn surface to a large extent, and the deep dyeability and swelling when made into yarn or woven or knitted fabric are insufficient. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 7-324239 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-56484 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention solves the above-mentioned problems, and has as its technical object to provide a polyester mixed fiber interlaced yarn that makes it possible to obtain woven and knitted fabrics that have a fluffy and bulky feel. [Means for solving the problem]

[0009] The present inventors have conducted extensive research to solve the above-mentioned problems, and have found that the above-mentioned problems can be solved by subjecting the yarn to a heat treatment to form a mixed fiber entangled yarn in which a specific number of bulky portions having a specific length and height are formed in the yarn, thereby arriving at the present invention.

[0010] That is, the present invention provides the following. 1. A polyester mixed fiber entangled yarn consisting of polyester yarn A and polyester yarn B, in which the entangled yarn contains 50% by mass or more of polyester yarn A and satisfies the following (1) and (2). (1) The yarn has 25 to 90 spread portions per meter of the yarn, each having a length of 5.5 to 8.5 mm and a height of 0.4 to 0.8 mm in the longitudinal direction of the yarn. (2) After heat treatment at 130°C for 30 minutes, the yarn has 200 to 300 bulky portions per meter, each bulky portion having a length of 2 to 4 mm and a height of 0.5 to 2.5 mm in the longitudinal direction of the yarn. 2. A polyester mixed fiber entangled yarn according to 1., wherein the polyester yarn A is a core-sheath composite multifilament yarn containing, as a single yarn, a core-sheath composite fiber in which a poorly soluble polyester resin is arranged in the core and a readily soluble polyester resin is arranged in the sheath. 3. A woven or knitted fabric containing the polyester mixed fiber interlaced yarn described in 1. or 2. 4. A method for producing a polyester mixed fiber entangled yarn, comprising the following steps (a) and (b): (A) A process of false-twisting polyester yarn YA having a hot water shrinkage rate of 40% or more using a fluid swirl nozzle under conditions of a heater temperature of 260°C or more and a twist / untwist tension ratio of 0.8 to 1.2 to obtain polyester false-twist textured yarn FA having a hot water shrinkage rate of 5% or less. (b) A step of doubling the polyester false twist textured yarn FA with a polyester yarn YB having a hot water shrinkage rate of 15% or more, interlacing the yarn, and compounding the yarn. [Effects of the Invention]

[0011] The polyester mixed fiber entangled yarn of the present invention is one in which a specific number of bulky portions of a specific length and height are formed in the yarn by subjecting it to heat treatment. Therefore, after weaving and knitting, heat treatment can be performed to obtain a woven or knitted fabric that has sufficient volume and bulkiness and also has excellent deep dyeability. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing one embodiment of a cross section perpendicular to the fiber axis direction of a core-sheath composite fiber used in polyester yarn A of the present invention after alkali elution. [Figure 2] 1 is a schematic diagram (partially enlarged) showing the appearance of the polyester mixed fiber entangled yarn of the present invention before and after heat treatment. [Figure 3] 1 is a schematic process diagram showing an example of a method for producing a polyester mixed fiber entangled yarn of the present invention. [Figure 4] FIG. 2 is a schematic process diagram showing an example of a method for producing a polyester mixed fiber entangled yarn of Comparative Examples 2 and 4. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present invention will be described in detail below.

[0014] [Polyester blended interlaced yarn] The polyester mixed fiber entangled yarn of the present invention (hereinafter sometimes referred to as mixed fiber entangled yarn) is an entangled yarn made of polyester yarn A and polyester yarn B. Polyester yarn A and polyester yarn B are made of polyester filaments, and the polyester filaments may be made of polyesters such as polyalkylene terephthalate. Specific examples include polyethylene terephthalate (PET), polybutylene terephthalate, and polytrimethylene terephthalate. In addition, in consideration of viscosity, thermal properties, compatibility, and the like, aromatic dicarboxylic acids such as isophthalic acid and 5-sulfoisophthalic acid; aliphatic dicarboxylic acids such as adipic acid, succinic acid, suberic acid, sebacic acid, and dodecanedioic acid; aliphatic diols such as ethylene glycol, propylene glycol, 1,4-butanediol, and 1,4-cyclohexanedimethanol; hydroxycarboxylic acids such as glycolic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxycaproic acid, hydroxypentanoic acid, hydroxyheptanoic acid, and hydroxyoctanoic acid; and aliphatic lactones such as ε-caprolactone may be copolymerized.

[0015] The polyester filaments may also contain additives such as antistatic agents, antibacterial agents, and deodorants to provide functionality.

[0016] The polyester yarn A is preferably a sheath-core composite multifilament yarn containing, as single yarns, sheath-core composite fibers each having a poorly soluble polyester resin in the core and a readily soluble polyester resin in the sheath. The polyester yarn A may have a round cross-sectional shape or a modified cross-sectional shape. The polyester yarn A is treated with a solvent such as alkali (alkali elution treatment) to elute the readily soluble polyester component. The remaining poorly soluble polyester component is preferably used to form a polyester yarn having an uneven cross-section perpendicular to the fiber axis direction, with projections and narrow grooves as shown in Figure 1. The alkali-soluble polyester resin is a conventionally known resin, such as one obtained by copolymerizing polyester with 5-sodium sulfoisophthalic acid. If the fiber surface of the polyester yarn A has an uneven shape, when light is irradiated onto the fiber surface, the irregular surface shape causes repeated diffuse reflection of the light, which is then absorbed inside the fiber, reducing the light reflected to the outside. This enables the expression of deeper colors. Furthermore, the fabric can be woven or knitted with a silky and smooth feel.

[0017] The uneven shape referred to in the present invention refers to a fiber surface having minute uneven portions as described below, and does not simply refer to the cross-sectional shape of an irregular cross-section yarn (for example, a polygonal cross-sectional shape such as a triangular cross-section or a hexagonal cross-section).

[0018] As a specific example of a method for making the fiber surface of polyester yarn A have an uneven shape, other than the above-mentioned method (method (1)) of forming an uneven shape by dissolving the easily soluble polyester resin that forms the sheath part of polyester yarn A, there can be mentioned a method (method (2)) of adding fine particles inactive to polyester during polymerization or spinning of polyester, spinning the polyester, and removing the fine particles by alkali dissolution treatment to form an uneven shape. Such a cross-sectional shape having an uneven shape may be present at the stage of mixed fiber entangled yarn, or may be formed by processing treatment when this mixed fiber entangled yarn is knitted or woven to obtain a woven or knitted fabric.

[0019] The width of the protrusions is preferably 0.3 to 1.0 μm, and the height is preferably very small, about 0.4 to 3.0 μm. The number of protrusions is preferably 15 or more, more preferably 15 to 35. Furthermore, the shapes of the protrusions and fine grooves are not particularly limited, but are preferably gear-shaped cross-sectional shapes in which the protrusions and fine grooves are alternately and approximately uniformly distributed on the fiber surface, as in the cross section of the polyester yarn shown in FIG. 1, and the cross section of the protrusions may be rectangular or trapezoidal.

[0020] The above-mentioned method (2) is described below. By subjecting polyester filament yarn containing microparticles to an alkali elution treatment and removing the microparticles present on the fiber surface, polyester yarn having microcrater-like irregularities can be obtained. The content of the microparticles is preferably 1 to 15 mass% of the total amount of polyester, and the particle size of the microparticles is preferably 2 μm or less, but both may be within a range that does not cause problems during spinning.

[0021] Examples of the types of fine particles used above include inorganic compounds such as ceramics (for example, oxides, sulfates, carbonates, phosphates, or silica of barium, calcium, magnesium, aluminum, or the like).

[0022] The single yarn fineness of polyester yarn A is not particularly limited, but in order to obtain a silky and smooth texture, it is preferably 10 dtex or less, and more preferably 2.5 to 5 dtex. The total fineness of polyester yarn A is preferably 50 to 250 dtex, and more preferably 60 to 200 dtex.

[0023] The hot water shrinkage rate of polyester yarn A is preferably 0 to 10%, more preferably 0 to 5%. When the hot water shrinkage rate is within the above range, the difference in hot water shrinkage rate with polyester yarn B, which will be described later, becomes large. By making the hot water shrinkage rate of polyester yarn A smaller than that of polyester yarn B in this way, it is possible to make the polyester yarn A float to the fiber surface and be unevenly distributed when the mixed fiber entangled yarn is heat-treated, and therefore the mixed fiber entangled yarn of the present invention has an excellent deep dyeing effect and is also excellent in fluffiness and bulkiness. The method for measuring the hot water shrinkage rate will be described later.

[0024] The polyester yarn B is preferably a high-shrinkage yarn with a hot water shrinkage rate of 15% or more, and more preferably 20% or more. Examples of polyester resins constituting the polyester yarn B with a hot water shrinkage rate of 15% or more include those obtained by copolymerizing a copolymerization component with an acid component constituting a polyester. Examples of copolymerization components include 2,2-bis-[4-(β-hydroxyethoxy)phenyl]propane (BHPP), an ethylene oxide adduct of bisphenol A (BA-EO), and isophthalic acid (IPA). It is preferable to use fibers whose main constituent is a copolymerized polyester resin containing at least one of these copolymerization components.

[0025] If the hot water shrinkage rate is less than 15%, the difference in hot water shrinkage rate with the low-shrinkage polyester yarn A is small, and the shrinkage of polyester yarn B is small in the heat treatment step, so that when the mixed entangled yarn of the present invention is heat treated, the polyester yarn A does not rise to the surface of the mixed entangled yarn and is not unevenly distributed, and both the polyester yarn A and the polyester yarn B are present on the surface of the mixed entangled yarn. Therefore, when made into a woven or knitted fabric, the deep dyeability is insufficient and the fabric has poor fluffiness and bulkiness, which is undesirable.

[0026] In the present invention, the difference in hot water shrinkage rate between polyester yarn A and polyester yarn B is preferably 15% or more, more preferably 18% or more. If the difference in hot water shrinkage rate is within this range, when the mixed fiber entangled yarn of the present invention is heat-treated, polyester yarn A tends to protrude and be unevenly distributed on the surface of the mixed fiber entangled yarn, and polyester yarn B tends to be present in the center of the mixed fiber entangled yarn.

[0027] The hot water shrinkage percentage of the mixed fiber entangled yarn of the present invention is preferably 12 to 27%, more preferably 15 to 25%. If the hot water shrinkage percentage is within the above range, when the mixed fiber entangled yarn is heat-treated, the mixed fiber entangled yarn as a whole, and in particular the polyester yarn B, will be appropriately shrunk, and the polyester yarn A will be unevenly distributed and raised to the surface of the mixed fiber entangled yarn.

[0028] The single yarn constituting the polyester yarn B preferably has a single yarn fineness of 2 to 20 dtex, more preferably 2 to 8 dtex, and the total fineness of the polyester yarn B is preferably 20 to 100 dtex, more preferably 25 to 80 dtex.

[0029] The polyester thread B may have a round cross section or a modified cross section, but is preferably round.

[0030] The polyester mixed fiber entangled yarn of the present invention is obtained by entangling the above-mentioned polyester yarn A and polyester yarn B. In the present invention, it is important to use a fluid entanglement treatment using an interlace nozzle as a means for entangling the mixed fibers. The details of the production method will be described later.

[0031] The interlacing number of the mixed fiber interlaced yarn is preferably 25 to 90 / m. If the interlacing number is less than 25 / m, polyester yarn A and polyester yarn B are likely to separate, and the two fibers may come apart during the knitting and weaving process. If the two fibers come apart, not only are problems likely to occur during the knitting and weaving process, but the difference in hot water shrinkage rate will prevent polyester yarn A from floating on the surface of the mixed fiber interlaced yarn or woven or knitted fabric, or from forming sufficient loops, making it difficult to achieve deep dyeability, fullness, and bulkiness, which is undesirable. Furthermore, if the interlacing number exceeds 90 / m, the yarns will be too tightly entangled, resulting in a stiff texture and poor drapeability of the resulting woven or knitted fabric. Furthermore, the interlacing will be more noticeable, which may reduce the aesthetic appeal of the appearance.

[0032] In the polyester mixed and entangled yarn of the present invention, which is obtained by mixedly entangling polyester yarn A and polyester yarn B, the polyester yarn A must be contained in an amount of 50% by mass or more, and preferably 60% by mass or more. If the content of polyester yarn A is less than 50% by mass, the deep dyeing effect will be reduced. On the other hand, if the content of polyester yarn A is too high, the content of polyester yarn B will be reduced, which may reduce the firmness and stiffness of the resulting woven or knitted fabric, so the upper limit is preferably 90% by mass.

[0033] On the other hand, in the polyester mixed fiber entangled yarn, all the remaining parts other than the polyester yarn A may be the polyester yarn B, and the polyester yarn B is preferably contained in an amount of 20 to 50 mass %.

[0034] The torque of the polyester mixed fiber entangled yarn is not particularly limited, but may be, for example, 45 T / M or more, preferably 50 T / M or more, and more preferably 55 T / M or more. If the torque is 45 T / M or more, it is possible to obtain a woven or knitted fabric having excellent bundling properties due to twisting and a firm and resilient feel.

[0035] Next, the entangled state of the mixed fiber entangled yarn of the present invention will be explained with reference to the drawings.

[0036] Figure 2(a) is a schematic diagram (partially enlarged) showing the appearance of the mixed fiber entangled yarn of the present invention (before heat treatment), and Figures 2(c) and (d) are schematic diagrams (partially enlarged) showing the appearance of the mixed fiber entangled yarn after heat treatment.

[0037] The mixed entangled yarn before heat treatment of the present invention is obtained by interlacing a raw yarn (mixed yarn) made of polyester yarn A and polyester yarn B, so that spread portions (unentangled portions) and bundled portions (entangled portions) are alternately formed in the longitudinal direction of the yarn.

[0038] The spread region X as shown in Fig. 2(a) is a portion where the polyester yarn A and the polyester yarn B are not bundled and remain in a spread state during interlace entanglement in the mixed entangled yarn manufacturing process, and where the spaces between the single yarns are expanded, resulting in a bulge. On the other hand, the bundled region Y is a portion where the polyester yarn A and the polyester yarn B are bundled by interlace entanglement.

[0039] The spread regions X and bundle regions Y are alternately present in the longitudinal direction of the yarn. The mixed fiber entangled yarn of the present invention has 25 to 90 spread regions X per 1 m of the yarn, each having a length of 5.5 to 8.5 mm in the longitudinal direction of the yarn and a height (yarn width) of 0.4 to 0.8 mm. If the number of spread regions X having the above length and height is less than 25 / m, the spread regions (bulky portions) will not protrude sufficiently from the yarn surface after heat treatment, resulting in poor deep dyeability and fluffiness / bulkiness. On the other hand, if the number exceeds 90 / m, entanglement will be noticeable in the obtained woven or knitted fabric, resulting in a poor appearance. In particular, to obtain a woven or knitted fabric excellent in deep dyeability and fluffiness / bulkiness, it is preferable that the number of spread regions be 35 to 85 / m per 1 m of the yarn. The length of the spread portion in the polyester mixed entangled yarn of the present invention refers to the length in the yarn longitudinal direction of the bulge formed by the expansion of the intervals between the single yarns in the mixed entangled yarn, as shown by the arrow in Fig. 2(a). Moreover, the height of the spread portion refers to the length to the lowest single yarn among the single yarns that exist at the point where a perpendicular line intersects with the single yarn at the highest position in the bulge formed by the single yarns in the mixed entangled yarn, as shown by the arrow in Fig. 2(b).

[0040] The length and height (yarn width) of the spread portions in the yarn longitudinal direction and the number of the spread portions in the mixed entangled yarn are measured as follows. (Measurement method) An initial load of 0.0882 cN / dtex is applied to the mixed entangled yarn, and a mark is made at 1 m. Next, under a light load of 0.00882 cN / dtex, the length and height of the spread portions are measured using an optical microscope (Keyence Corporation's "Microscope VHX-900"), and the number of spread portions with a length of 5.5 to 8.5 mm and a height (yarn width) of 0.4 to 0.8 mm per 1 meter of yarn is calculated. At this time, the measurement is made with N=10, and the average value is calculated.

[0041] Next, the mixed and entangled yarn of the present invention after heat treatment will be described.

[0042] When the mixed entangled polyester yarn of the present invention, which is obtained by mixedly entangled polyester yarn A and polyester yarn B, is heat-treated, polyester yarn B undergoes greater heat shrinkage due to the difference in hot water shrinkage rate between polyester yarn A and polyester yarn B, resulting in a mode in which a large amount of polyester yarn B is arranged at the center of the mixed entangled yarn, while a large amount of polyester yarn A is arranged on the surface. Specifically, as exemplified in Fig. 2, the mixed entangled yarn of Fig. 2(a) before heat treatment becomes a mode such as Fig. 2(c) or 2(d) after heat treatment, in which polyester yarn A, which has less heat shrinkage, rises to the yarn surface mainly between each bundled portion, forming bulky portions Z. After heat treatment, bulky portions Z and bundled portions Y' are alternately present in the yarn longitudinal direction, but the bulky portions Z are shorter in length in the yarn longitudinal direction and larger in height (yarn width) than the spread portions X before heat treatment. Furthermore, since the overall length of the mixed and entangled yarn is shortened due to the thermal shrinkage of at least the polyester yarn B, the number of bulky portions Z and bundled portions Y' present per meter of yarn tends to increase.

[0043] The mixed entangled yarn of the present invention, after heat treatment at 130°C for 30 minutes, has 200 to 300 bulky portions per meter of yarn, each having a length of 2 to 4 mm in the yarn longitudinal direction and a height of 0.5 to 2.5 mm. In the present invention, the mixed entangled yarn before heat treatment has specific spread portions, and polyester yarn A and polyester yarn B have different heat shrinkage rates, so that the mixed entangled yarn can have the specific bulky portions after heat treatment. When the number of bulky portions is within the above range, the yarn is sufficiently raised on the yarn surface and the woven / knitted fabric surface, resulting in excellent deep dyeability and fluffy / bulky feel. In particular, to obtain woven / knitted fabrics excellent in deep dyeability and fluffy / bulky feel, it is preferable that the number of bulky portions be 220 to 280 per meter.

[0044] The length and height (yarn width) of the bulky portion in the yarn longitudinal direction and the number thereof are measured in the same manner as the measuring method for the spread portion of the mixed entangled yarn before the heat treatment described above.

[0045] The total fineness of the mixed fiber entangled yarn of the present invention is preferably 50 to 200 dtex, more preferably 80 to 150 dtex. The strength of the mixed fiber entangled yarn is preferably 1.0 cN / dtex or more. The elongation is preferably 5% to 30%, more preferably 10% to 22%.

[0046] The mixed fiber entangled yarn of the present invention has excellent deep dyeability when used as a woven or knitted fabric, and in particular, when the fiber surface of the polyester yarn A has an uneven shape, the unevenness of the surface makes the deep dyeability even better. Therefore, the mixed fiber entangled yarn of the present invention has an L* value of preferably less than 11.8, more preferably less than 11.5, when dyed as a tubular knitted fabric using a specific dyeing recipe. The knitting and dyeing recipe of the tubular knitted fabric will be described later in the examples.

[0047] [Woven and knitted fabrics] The woven or knitted fabric of the present invention is obtained by knitting or weaving the mixed fiber entangled yarn of the present invention. The mixing ratio of the mixed fiber entangled yarn in the woven or knitted fabric of the present invention is, for example, preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and particularly preferably 100% by mass.

[0048] The woven or knitted fabric of the present invention may be used without heat treatment, or may be heat treated to develop bulky portions in the mixed and intertwined yarns in the woven or knitted fabric.

[0049] When the woven or knitted fabric of the present invention is heat-treated before use, the woven or knitted fabric may be immersed in hot water for a predetermined period of time to sufficiently heat-shrink the polyester yarn B. Heat treatment conditions include, for example, about 80 to 135°C for about 10 to 30 minutes. By sufficiently heat-shrinking the polyester yarn B through such heat treatment, the polyester yarn B is largely arranged at the center of the mixed and entangled yarn, while the polyester yarn A is unevenly distributed on the surface of the fiber, resulting in a woven or knitted fabric with excellent deep dyeability, volume, and bulkiness. The heat treatment may be carried out on the grey fabric of a woven or knitted fabric, or may be carried out during the scouring and dyeing processes. The heat shrinkage treatment of this embodiment will be described below with an example. First, the grey fabric is scoured. Scouring may be carried out by a continuous or batch method at a temperature of 80 to 130°C. Usually, it is preferably carried out by a batch method at 100°C or less, and it is particularly preferably carried out using a high-pressure liquid jet dyeing machine equipped with a jet nozzle. After scouring, presetting may be carried out as necessary. Presetting is usually carried out by dry heat treatment at 170 to 200°C for 30 to 120 seconds using a pin tenter. Thereafter, dyeing is carried out according to a conventional method. Final setting may be carried out as necessary.

[0050] Furthermore, when the polyester yarn A in the mixed entangled yarn is one that forms an uneven shape on the fiber surface by alkali elution treatment, for example, the above-mentioned grey fabric may be scoured and then immersed in an alkali solution to elute the alkali-soluble polyester component and fine particles in the polyester yarn A, thereby forming protrusions and fine grooves on the fiber surface. By carrying out the alkali elution treatment in addition to the heat treatment in this way, the polyester yarn A in the woven or knitted fabric obtained after the treatment will develop bulky parts with an uneven shape on the fiber surface, and therefore the woven or knitted fabric can be made to have even better deep dyeability, volume, and bulkiness.

[0051] The woven or knitted fabric of the present invention may be a woven fabric or a knitted fabric. The weave is not particularly limited; for example, woven fabrics may be plain weave, twill weave, satin weave, or a multi-layer weave as needed, while knitted fabrics may be circular knit jersey, smooth, or warp knit tricot, or a multi-layer weave as needed. Furthermore, various known post-treatments such as water-repellent finishes, softening finishes, and anti-static finishes may be applied depending on the purpose. Furthermore, for the purpose of improving the texture, etc., the deep-dyeable textured yarn of the present invention may be subjected to additional twisting or plying to form a woven or knitted fabric.

[0052] Furthermore, the woven or knitted fabric of the present invention is not limited in terms of yarn density, etc., as long as it achieves the effects of the present invention, but the CF (cover factor) when protrusions and narrow grooves are formed on the surface of polyester yarn A by alkali weight reduction treatment is preferably 1000 to 3500, more preferably 1500 to 3000. When the CF is in the above range, it becomes possible to achieve stretchability and a silky, smooth texture suitable for clothing applications.

[0053] By subjecting the woven or knitted fabric of the present invention to heat treatment as described above, bulky portions appear in the mixed fiber entangled yarn, giving the fabric a fluffy feel and bulkiness. The thickness of the woven or knitted fabric before and after heat treatment is not limited because it varies depending on the fineness of the mixed fiber entangled yarn and the density of the woven or knitted fabric, but it is preferable that the change in thickness between before and after heat treatment is large, and for example, the rate of change (thickness after heat treatment / thickness before heat treatment) is preferably 1.5 times or more, more preferably 1.8 times or more, and even more preferably 1.9 times or more.

[0054] The woven or knitted fabric of the present invention is heat-treated to develop bulky portions in the mixed fiber entangled yarn, forming voids, which give the fabric a fluffy feel and result in a soft texture and excellent drape. Furthermore, since the mixed fiber entangled yarn of the present invention does not have excessive crimp, stretchability can be suppressed. Therefore, the woven or knitted fabric of the present invention can be used for clothing applications, and is particularly suitable for applications such as blouses, dresses, and black formal wear.

[0055] [Method of manufacturing mixed fiber entangled yarn] The method for producing the mixed entangled yarn of the present invention is not limited as long as it is a method that can produce the mixed entangled yarn having the above-mentioned specific spread portions and bulky portions, but it is preferable to produce it by carrying out the following steps (a) and (b). (A) A process of false-twisting polyester yarn YA having a hot water shrinkage rate of 40% or more using a fluid swirl nozzle under conditions of a heater temperature of 260°C or more and a twist / untwist tension ratio of 0.8 to 1.2 to obtain polyester false-twist textured yarn FA having a hot water shrinkage rate of 5% or less. (b) A step of doubling the polyester false twist textured yarn FA with a polyester yarn YB having a hot water shrinkage rate of 15% or more, interlacing the yarn, and compounding the yarn.

[0056] Hereinafter, one embodiment of a preferred method for producing the mixed and entangled yarn of the present invention will be described.

[0057] In the method for producing a mixed entangled yarn of the present invention, first, a polyester yarn YA is prepared as a supply yarn, and polyester false twist textured yarn FA is obtained through the above-mentioned step (A). Next, polyester false twist textured yarn FA and polyester yarn YB are prepared as supply yarns for interlacing, and through the interlacing process, polyester false twist textured yarn FA becomes polyester yarn A, and polyester yarn YB becomes polyester yarn B, thereby obtaining a mixed entangled yarn. The above step (A) will be explained below.

[0058] Process (A) In step (a), polyester yarn YA having a hot water shrinkage of 40% or more is false-twisted using a fluid swirl nozzle at a heater temperature of 260°C or higher and a twist / untwist tension ratio of 0.8 to 1.2, to obtain polyester false-twist textured yarn FA having a hot water shrinkage of 5% or less. The hot water shrinkage of the polyester yarn YA is preferably 40% or higher, more preferably 45% or higher. As the polyester yarn YA, it is preferable to use a partially oriented undrawn yarn (POY) obtained by melt-spinning a polyester raw polymer and then winding it up, preferably at a spinning speed of 2000 m / min to 3500 m / min.

[0059] Hereinafter, one embodiment of the manufacturing method in which POY is used as the polyester yarn YA will be described. Generally, false-twisting while drawing is used as a method for obtaining false-twisted yarn from POY. The spindle and friction methods are generally used for false-twisting while drawing, but both methods require a certain level of draw ratio and processing tension because lowering the draw ratio can affect operability, causing yarn breakage due to ballooning and leaving the yarn untwisted. This promotes yarn orientation, resulting in poor dyeability and a tendency for the resulting yarn to crimp. On the other hand, in the present invention, false twisting is performed using a fluid swirl nozzle under specific conditions, which suppresses the progression of the orientation degree of the supplied yarn, and also results in a yarn with a high thermal shrinkage rate and significantly improved deep dyeability.

[0060] The false twisting conditions using a fluid swirl nozzle are as follows: polyester yarn YA (POY) with a hot water shrinkage of 40% or more is false twisted at a heater temperature of 260°C or higher and a twist / untwist tension ratio of 0.8 to 1.2. The heater temperature is preferably 265°C or higher, and more preferably 270 to 300°C. A heater temperature within this range ensures that the polyester yarn YA does not have an excessively high degree of orientation, and that the polyester yarn YA is heat-shrunk, resulting in a false twisted yarn FA with a low heat shrinkage. Furthermore, a twist / untwist tension ratio of 0.8 to 1.2 allows the polyester yarn YA to be false twisted with an appropriate amount of tension applied without substantial stretching. The twist / untwist tension ratio can be calculated using the following formula. The fluid swirl nozzle may be, for example, the fluid swirl nozzle shown in FIG. 9 of JP-A-4-214431. Twist / untwist tension ratio = untwist tension (T2) / twist tension (T1)

[0061] In the present invention, by performing false twisting under the above conditions, the resulting polyester false twist textured yarn FA can have a heat shrinkage of 5% or less, and since the degree of orientation is not too high compared to the spindle and friction methods, it can have better deep dyeability. Furthermore, because false twisting is performed without substantial stretching, the resulting false twist textured yarn FA does not have too strong crimp and can be made into a yarn similar to raw silk.

[0062] The false twist coefficient is preferably 2000 to 22000, and more preferably 3000 to 20000. A false twist coefficient of less than 2000 is undesirable because the fiber-opening effect during fluid swirl processing is poor and poor entanglement is likely to occur. A false twist coefficient of more than 22000 is undesirable because the twisting action of the fibers due to twisting becomes excessively strong and the internal orientation of the fibers progresses too far, which leads to a change in the direction of decreasing deep dyeability. The false twist coefficient is calculated by the following formula using the number of false twists (unit: T / M) and the yarn fineness T (unit: denier). Twist coefficient = number of twists × T 1 / 2

[0063] Furthermore, when the above-mentioned POY is used as the polyester yarn YA to obtain the polyester false twist textured yarn FA, the single yarn fineness of the POY is preferably 10 dtex or less, more preferably 2 to 7 dtex, and even more preferably 3 to 5 dtex. The total fineness is preferably 50 to 250 dtex, and more preferably 70 to 200 dtex. By setting the single yarn fineness and total fineness of the POY within these ranges, the single yarn fineness and total fineness of the polyester false twist textured yarn FA obtained through the false twisting process can be set within the above ranges. The elongation of the POY is preferably 100 to 200%, more preferably 120 to 170%. The preferred cross-sectional shape of the single yarn of the polyester yarn YA is the same as that of the polyester yarn A.

[0064] The polyester false twist textured yarn FA obtained after false twist texture preferably has a hot water shrinkage rate of 5% or less, more preferably 4% or less. If the hot water shrinkage rate is as low as 5% or less, polyester yarn A is less likely to shrink in heat than polyester yarn B when the mixed fiber entangled yarn of the present invention is heat treated, and therefore polyester yarn A can be unevenly distributed on the surface of the mixed fiber entangled yarn.

[0065] The polyester false twist textured yarn FA preferably has a single yarn fineness of 10 dtex or less, and more preferably 2.5 to 5 dtex. The total fineness is preferably 50 to 250 dtex, and more preferably 60 to 200 dtex. By setting the single yarn fineness and total fineness of the polyester false twist textured yarn FA within these ranges, when the mixed fiber entangled yarn is produced through the process described below, the single yarn fineness of the polyester yarn A can be set within the above range. Furthermore, the polyester yarn A is well entangled with the polyester yarn YB during the mixed fiber entanglement, and the woven or knitted fabric can have sufficient deep dyeability and appropriate volume and bulk.

[0066] The elongation of the polyester false twist textured yarn FA is preferably 10 to 30%, more preferably 15 to 28%. When the elongation of the polyester false twist textured yarn FA is within the above range, yarn breakage during false twist texture is unlikely to occur, and a mixed fiber entangled yarn can be obtained with good operability.

[0067] Next, step (b) will be described.

[0068] Process (b) In step (b), the polyester false twist textured yarn FA obtained above is combined with a polyester yarn YB having a hot water shrinkage rate of 15% or more, interlaced, and composited to obtain a polyester mixed entangled yarn of the present invention. In the present invention, it is necessary to perform interlacing in the composite step to form bundled portions and spread portions in the yarn length direction of the mixed entangled yarn and to obtain the mixed entangled yarn of the present invention having the above-mentioned properties. When a method other than interlacing is used, for example, mixed entanglement using a Taslan nozzle, loop fuzz and slack are formed throughout the mixed entangled yarn. Therefore, when the mixed entangled yarn is heat-treated, the polyester yarn A and the polyester yarn B are in a disordered state throughout the yarn, and both yarns are mixed on the surface of the yarn, resulting in a yarn that does not have the configuration of the polyester mixed entangled yarn of the present invention.

[0069] The hot water shrinkage rate of polyester yarn YB, which is the supply yarn for polyester yarn B, is preferably 15% or more, and more preferably 20% or more. If the hot water shrinkage rate of polyester yarn YB is as high as 15% or more, polyester yarn B is more likely to be heat-shrunk than polyester yarn A when the mixed fiber entangled yarn of the present invention is heat-treated, and therefore, a state in which polyester yarn A is unevenly distributed on the surface of the mixed fiber entangled yarn and polyester yarn B is present at the center of the mixed fiber entangled yarn is easily formed.

[0070] The single yarn fineness of the polyester yarn YB is preferably 2 to 20 dtex, more preferably 2 to 8 dtex. By setting the single yarn fineness of the polyester yarn YB within this range, when the polyester yarn YB is made into a mixed fiber entangled yarn through the process described below, the single yarn fineness of the polyester yarn YB can be set within the above range. Furthermore, during the mixed fiber entanglement, the polyester yarn YB is well entangled with the polyester false twist textured yarn FA, and the woven or knitted fabric can have sufficient deep dyeability and appropriate fullness and bulkiness. From the viewpoint of further improving the firmness and body, the total fineness of the polyester yarn YB is preferably 20 to 100 dtex, more preferably 25 to 80 dtex. Furthermore, the preferred cross-sectional shape of the single yarn of the polyester yarn YB is the same as that of the polyester yarn B described above.

[0071] The elongation of the polyester yarn YB is preferably 10 to 30%, more preferably 15 to 28%. When the elongation of the polyester yarn YB is within the above range, yarn breakage is unlikely to occur during false twisting, and a mixed fiber entangled yarn can be obtained with good operability.

[0072] Next, in the combining step, the polyester false twist textured yarn FA and the polyester yarn YB are combined and combined using an interlace nozzle to obtain the polyester mixed fiber entangled yarn of the present invention.

[0073] Overview of the manufacturing process Next, one embodiment of the method for producing the mixed and entangled yarn of the present invention will be described with reference to FIG.

[0074] First, the polyester yarn YA is false-twisted using a fluid rotation nozzle under specified conditions. Specifically, the polyester yarn YA is false-twisted under conditions of a heater temperature of 260°C or higher and a twist / untwist tension ratio of 0.8 to 1.2. Specifically, the polyester yarn YA is introduced into the supply roller 1, passes through the heat treatment heater 2 and the fluid rotation nozzle 3, and is drawn out from the first take-up roller 4 to obtain the polyester false-twist textured yarn FA (step (a)). Here, the space between the supply roller 1 and the first take-up roller 4 is the false-twist region. Specifically, the space between the supply roller 1 and the fluid rotation nozzle 3 is the twist region T1, and the space between the fluid rotation nozzle 3 and the first take-up roller 4 is the untwist region T2.

[0075] The false twisting speed is preferably 200 to 700 m / min from the viewpoint of suppressing yarn breakage and poor entanglement, and it is preferable to specify the processing speed, draw ratio, etc. The processing speed refers to the yarn speed when the yarn is drawn out from the first take-up roller 4, i.e., the surface speed of the first take-up roller 4. The draw ratio is preferably 1.3 or less. Here, the draw ratio refers to the ratio between the surface speed of the supply roller 1 and the surface speed of the first take-up roller 4. If the draw ratio is 1.3 or less, a polyester false twisted yarn FA can be obtained that has a degree of orientation that is not too high and has little crimp.

[0076] Next, the polyester yarn YB is introduced from the first take-up roller 4, and the polyester false twist textured yarn FA and the polyester yarn YB are aligned and guided to the fluid treatment processing area by the first take-up roller 4, where they are mixed and entangled by fluid injection from the interlace nozzle 5 (step (b)), thereby obtaining the polyester mixed and entangled yarn of the present invention.

[0077] The overfeed rate in the combining step is not particularly limited, but is preferably 1.0 to 3.0%. In the present invention, the overfeed rate is a value calculated by the formula: overfeed rate = (V1 - V2) / V2 × 100 (%), where V1 is the yarn speed immediately before being introduced into the interlace nozzle and V2 is the yarn speed immediately after passing through the interlace nozzle.

[0078] The air pressure conditions in the combining step are not particularly limited, but may be, for example, 0.1 to 0.5 MPa, and preferably 0.15 to 0.4 MPa. The resulting polyester mixed entangled yarn passes through a second take-up roller 6 and is wound into a package by a winding roller 7. [Example]

[0079] The present invention will be described in more detail below with reference to examples, in which various property values ​​are measured and evaluated.

[0080] (1) Length, height (yarn width), and number of spread and bulky parts in the yarn longitudinal direction Using the obtained polyester mixed entangled yarn, the spread portions before the heat treatment and the bulky portions after the heat treatment were measured by the above-mentioned method.

[0081] (2) Single yarn size, total size The single yarn fineness and total fineness of the polyester yarn YA and polyester yarn YB, and the total fineness of the resulting polyester mixed fiber entangled yarn were measured in accordance with JIS L10138.3.1. (3) Number of confounds The obtained polyester mixed and intertwined yarn was measured according to the following method. A stand approximately 100 cm long was prepared, with a chuck at the top and 1 cm below it as the origin. One end of the sample was clamped in the chuck at the top of the scale, and the sample was hung vertically. A load of 0.1 cN / dtex was applied to the bottom of the sample, and marks were made at the top and bottom with a marking length of 50 cm. Next, a hook was inserted into the marking at the top of the sample so as to divide the yarn bundle in two, and the hook was lowered. The part where the hook stopped due to entanglement of the yarn was considered to be the entangled part. This process was repeated to count the number of entanglements in the 50 cm marking length. Five measurements were made in this manner, and the average number of entanglements was calculated, which was then used to calculate the number of entanglements per meter using the following formula: Number of interlaces (pieces / m) = (average number of interlaces / 50cm) x 2

[0082] (4) Torque A 200 cm section of the obtained polyester mixed fiber entangled yarn is used as a sample, and the sample is hung in a U-shape using a pin as a fulcrum (positioned so that both ends of the sample are at the top and the pin acting as the fulcrum is at the bottom). An initial load of 0.33 cN / dtex is applied to both upper ends of the sample to fix it in place. A load of 0.003 cN / dtex is applied to the sample part of the pin acting as the fulcrum, and then the pin is removed and the sample is allowed to self-rotate while suspended. When the self-rotation stops, the twist is detected, the number of rotations is found, and the number of twists per meter is calculated as torque (T / M).

[0083] (5) Elongation The elongation of the polyester yarn YA, polyester yarn YB, and the obtained polyester mixed fiber entangled yarn was measured according to the elongation measurement method specified in "8.5.2 Standard time test" of "JISL1013:2021 Chemical fiber filament yarn test method."

[0084] (6) Hot water shrinkage The hot water shrinkage rates of polyester yarn YA, polyester yarn YB, polyester yarn A, polyester yarn B, and the resulting polyester mixed and interlaced yarn were measured according to the measurement method for dimensional change rate specified in "JISL1013:2021 Test Methods for Chemical Fiber Filament Yarns," "8.18.1 Hot Water Dimensional Change Rate, Method A (Hank Dimensional Change Rate)." Note that the hot water shrinkage rates of polyester yarn A and polyester yarn B were measured by removing the yarn just before it was inserted into the interlace nozzle during the manufacturing process, and separating the combined yarn into polyester false-twisted yarn FA and polyester yarn YB.

[0085] (7) L* value The resulting cylindrical knit fabric was scoured, alkaline eluted, and dyed using the following dyeing formula. It was then heat-treated at 180°C for 30 seconds to obtain a black cylindrical knit fabric. This cylindrical knit fabric was used as a sample, and its reflectance was measured using a Macbeth MS-CE3100 spectrophotometer, and the L* value was calculated using the CIE Lab color difference formula. The smaller the L* value, the deeper the color. <Dyeing formula> (scouring) Scouring agent: Sunmol FL (Nicca Chemical Co., Ltd.) 2g / L ·Temperature x time: 80℃ x 20 minutes (Alkaline elution) Caustic soda: 10g / L ·Temperature x time: 98℃ x 30 minutes (staining) Dye: Dianix Black HG-FS (Mitsubishi Chemical Hoechst, disperse dye) 15% owf Auxiliary agent: Nikka Sunsalt SN-130 (manufactured by Nicca Chemical Co., Ltd.) 0.5g / L : Acetic acid 0.2cc / L ·Temperature x time: 135℃ x 30 minutes ·Bath ratio: 1:50

[0086] (8) Thickness The thickness of the obtained tubular knitted fabric (before heat treatment) and the knitted fabric after dyeing and heat treatment (after heat treatment) was measured at 10 points each using a thickness measuring device (manufactured by Ozaki Seisakusho Co., Ltd.: product name Peacock H), and the average values ​​were used as the thickness (mm) of the knitted fabric before and after heat treatment.

[0087] (9) Fullness The knitted fabrics obtained in the examples and comparative examples after dyeing and heat treatment were evaluated for fluffiness by touch according to the following criteria. ○: Very fluffy, the bulky part does not collapse when the knitted fabric surface is touched, the knitted fabric does not collapse, and the fluffy feeling is maintained △: When the knitted surface is touched, the bulky part is slightly crushed and the fluffy feeling is slightly lacking. ×: When the knitted fabric surface is touched, the bulky part is crushed, the knitted fabric is sagging, and the fluffy feeling is lacking.

[0088] Example 1 For the polyester yarn YA, an 84 dtex, 24 filament polyester sheath-core composite yarn (a multifilament yarn consisting of polyester sheath-core composite fibers in which the sheath is made of alkali-soluble polyester resin and the core is made of alkali-insoluble polyester resin, with 20 protrusions on the core cross section; hot water shrinkage rate: 50%) was prepared, and for the polyester yarn YB, a 32 dtex, 12 filament copolymer polyester yarn (a multifilament yarn whose main component is a copolymer polyester resin containing BHPP, BA-EO, and IPA as copolymer components; hot water shrinkage rate: 24%) was prepared.

[0089] Next, false twisting and mixed entanglement were performed under the conditions shown in Table 1. That is, according to the manufacturing process shown in Fig. 3, polyester yarn YA was introduced into supply roller 1 and false twisted using fluid swirl nozzle 3 at a heater temperature of 280°C and a twist / untwist tension ratio of 1.1, to obtain polyester false twist textured yarn FA. Next, polyester yarn YB was introduced through first take-up roller 4, and the polyester false twist textured yarn FA and polyester yarn YB were led into the fluid treatment processing zone in an aligned state, where they were mixed entangled by fluid spray from interlace nozzle 5 ("P-212" manufactured by Heberlein), to obtain a polyester mixed entangled yarn. The obtained polyester mixed entangled yarn contained 70% by mass of polyester yarn A and included entangled portions (concentrated portions) and non-entangled portions (open portions) in the yarn longitudinal direction.

[0090] Next, using only the obtained mixed interlaced yarn, a cylindrical knitted fabric (approximately 30 cm) was made using a cylindrical knitting machine (boiler diameter: 3.5 inches, number of needles: 260N) manufactured by Eiko Sangyo Co., Ltd. Next, after scouring, alkali elution and dyeing using the same dyeing recipe and conditions as above, the fabric was heat-treated at 180°C for 30 seconds to obtain a knitted fabric.

[0091] Example 2 A polyester mixed entangled yarn was obtained by carrying out false twisting and mixed entanglement treatment under the conditions shown in Table 1 in the same manner as in Example 1, except that a polyester core-sheath composite yarn of 168 dtex and 48 filaments was used as the polyester yarn YA. Next, a tubular knitted fabric was obtained using the obtained polyester mixed entangled yarn in the same manner as in Example 1, and then the fabric was subjected to scouring, alkali elution, dyeing and heat treatment to obtain a dyed and heat-treated knitted fabric.

[0092] Comparative Example 1 A polyester mixed entangled yarn was obtained by carrying out false twisting and mixed entanglement treatment under the conditions shown in Table 1 in the same manner as in Example 1, except that a 56 dtex 24 filament polyester drawn yarn (multifilament yarn mainly composed of polyethylene terephthalate resin, hot water shrinkage of 7%) was used as the polyester yarn YB. Next, a tubular knitted fabric was obtained using the obtained polyester mixed entangled yarn in the same manner as in Example 1, and then the fabric was subjected to scouring, alkali elution, dyeing and heat treatment to obtain a dyed and heat-treated knitted fabric.

[0093] Comparative Example 2 Instead of using an interlace nozzle for mixed fiber entanglement, a Taslan nozzle ("T-341" manufactured by Heberlein) was used, and false twisting and mixed fiber entanglement were performed under the conditions shown in Table 1 and according to the manufacturing process shown in Figure 4. That is, polyester yarn YA was introduced into supply roller 1, and false twisting was performed using fluid swirl nozzle 3 under conditions of a heater temperature of 210°C and a twist / untwist tension ratio of 1.1, to obtain polyester false twist textured yarn FA. Next, polyester yarn YB was introduced from second take-up roller 8, and the polyester false twist textured yarn FA and polyester yarn YB were led into the fluid treatment processing zone in an aligned state, where they were mixed entangled by fluid spray from the Taslan nozzle, to obtain a polyester mixed fiber entangled yarn. The obtained polyester mixed fiber entangled yarn was in a state where it was entirely entangled in the yarn longitudinal direction, and entangled portions (concentrated portions) and unentangled portions (spread portions) were not alternately formed. Next, a cylindrical knit fabric was obtained in the same manner as in Example 1 using the obtained polyester mixed interlaced yarn, and then the fabric was subjected to scouring, alkali elution, dyeing and heat treatment to obtain a dyed and heat treated knit fabric.

[0094] Comparative Example 3 A polyester mixed entangled yarn was obtained in the same manner as in Example 1, except that false twisting and mixed entanglement treatment were carried out under the conditions shown in Table 1. Next, a tubular knitted fabric was obtained using the obtained polyester mixed entangled yarn in the same manner as in Example 1, and then the fabric was subjected to scouring, alkali elution, dyeing and heat treatment to obtain a dyed and heat-treated knitted fabric.

[0095] Comparative Example 4 False twisting and mixed entanglement treatment were carried out using a Taslan nozzle under the conditions shown in Table 1 in the same manner as in Comparative Example 2, except that a 156 dtex, 48 filament polyester core-sheath composite yarn was used as the polyester yarn YA and an 83 dtex, 24 filament polyester drawn yarn (a multifilament yarn mainly composed of polyethylene terephthalate resin, hot water shrinkage of 7%) was used as the polyester yarn YB, to obtain an entangled polyester mixed yarn. The obtained entangled polyester mixed yarn was in an entangled state overall in the longitudinal direction of the yarn, and entangled portions (concentrated portions) and unentangled portions (open portions) were not alternately formed. Next, a tubular knitted fabric was obtained using the obtained entangled polyester mixed yarn in the same manner as in Example 1, and then the fabric was scoured, alkali eluted, dyed, and heat-treated to obtain a dyed and heat-treated knitted fabric.

[0096] Comparative Example 5 False twisting and mixed fiber entanglement were performed under the conditions shown in Table 1 in the same manner as in Example 1, except that an 84 dtex 24 filament polyester sheath-core composite yarn (a multifilament yarn consisting of polyester sheath-core composite fibers in which the sheath was made of an alkali-soluble polyester resin and the core was made of a poorly alkali-soluble polyester resin, and the number of protrusions on the cross section of the core was 20; hot water shrinkage: 50%) was used as the polyester yarn YA, and a 58 dtex 24 filament polyester conjugate yarn (a drawn yarn (elongation: 23%; hot water shrinkage: 5%), obtained by side-by-side conjugate spinning using PET, a copolymer of 8 mol% isophthalic acid and 5 mol% 2,2-bis[4-(2-hydroxyethoxy)phenyl]propane, with an intrinsic viscosity [η] of 0.63 as the first component and PET with an intrinsic viscosity [η] of 0.53 as the second component) was used as the polyester yarn YB. Next, a cylindrical knit fabric was obtained in the same manner as in Example 1 using the obtained polyester mixed interlaced yarn, and then the fabric was subjected to scouring, alkali elution, dyeing and heat treatment to obtain a dyed and heat treated knit fabric.

[0097] The results of Examples 1 and 2 and Comparative Examples 1 to 5 are shown in Table 1.

[0098] [Table 1]

[0099] As is clear from Table 1, the polyester mixed entangled yarns obtained in Examples 1 and 2 contained 50% by mass or more of polyester yarn A and had specific numbers or more of spread portions (before heat treatment) and bulky portions (after heat treatment) having specific lengths and heights. Furthermore, after heat treatment, a large amount of polyester yarn B was located at the center of the mixed entangled yarn, while polyester yarn A was unevenly distributed on the fiber surface. Therefore, the resulting dyed knitted fabrics had volume and bulkiness, and almost no loop fuzz or slack was formed. Even when the knitted fabric surface was touched, the specific bulky portions were maintained, so the bulky portions were not crushed and the knitted fabric did not sag, maintaining the volume. Furthermore, because polyester yarn A had an uneven fiber surface, the deep dyeability was even better.

[0100] On the other hand, in the polyester mixed entangled yarn obtained in Comparative Example 1, since the heat shrinkage rate of polyester yarn B was small, the polyester yarn A was not lifted much on the yarn surface after heat treatment, and polyester yarn B also partially appeared on the yarn surface. Therefore, there were few bulky parts having a specific length and height, and the obtained knitted fabric was inferior in volume and bulkiness, and also in deep dyeability.

[0101] The polyester mixed entangled yarn obtained in Comparative Example 2 was in a state where the entire yarn was entangled by the taslan processing, the number of spread portions having a specific length and height was small, and both polyester yarn A and polyester yarn B appeared on the yarn surface after heat treatment, so bulky portions having a specific length and height were hardly formed. Therefore, although the obtained knitted fabric had a bulky feel, the bulky portions were crushed when touched with the knitted fabric surface, the knitted fabric sagged, and the fluffiness was poor. In addition, the deep dyeability was also poor. Furthermore, because loop fuzz and slack were formed throughout the yarn, the loops got caught on each other, resulting in poor operability during weaving.

[0102] The polyester mixed fiber entangled yarn obtained in Comparative Example 3 had a small number of entanglements (bundle parts) and a small number of spread parts, and therefore had a small number of bulky parts having a specific length and height after heat treatment. As a result, loop fluff was generated on the yarn surface, and the bulky parts of the obtained knitted fabric were easily crushed by touching the knitted fabric surface, and the knitted fabric was easily worn down. In addition, the deep dyeability was also poor.

[0103] The polyester mixed entangled yarn obtained in Comparative Example 4 was in a state where the entire yarn was entangled by the taslan processing, the number of spread portions having a specific length and height was small, and both polyester yarn A and polyester yarn B appeared on the yarn surface after heat treatment, so bulky portions having a specific length and height were hardly formed. Therefore, although the obtained knitted fabric had a bulky feel, the bulky portions were crushed when touched with the knitted fabric surface, the knitted fabric sagged, and the fluffiness was poor. In addition, the deep dyeability was also poor. Furthermore, because loop fuzz and slack were formed throughout the yarn, the loops got caught on each other, resulting in poor operability during weaving.

[0104] In the polyester mixed entangled yarn obtained in Comparative Example 5, since polyester yarn B was a side-by-side type yarn, polyester yarn B formed crimps after heat treatment, and the amount of polyester yarn A lifted from the yarn surface was small. As a result, there were few bulky parts with a specific length and height after heat treatment, and loop fuzz was also formed, so the obtained knitted fabric was inferior in bulkiness and had insufficient deep dyeability. [Explanation of symbols]

[0105] X Spreading section Y, Y' focusing section Z Bulky part 1 Supply roller 2 Heat treatment heater 3 Fluid Swirl Nozzle 4 First take-off roller 5 interlaced nozzles 6 Second take-off roller 7 Winding roller 8 Second supply roller 9 Taslan nozzle

Claims

1. A polyester mixed fiber entangled yarn comprising polyester yarn A and polyester yarn B, wherein the entangled yarn contains 50% by mass or more of polyester yarn A and satisfies the following (1) and (2): (1) The yarn has 25 to 90 spread portions each having a length of 5.5 to 8.5 mm and a height of 0.4 to 0.8 mm in the longitudinal direction of the yarn. (2) After heat treatment at 130°C for 30 minutes, the yarn has 200 to 300 bulky portions per meter, each bulky portion having a length of 2 to 4 mm and a height of 0.5 to 2.5 mm in the longitudinal direction of the yarn.

2. The polyester mixed fiber entangled yarn according to claim 1, wherein the polyester yarn A is a core-sheath composite multifilament yarn containing, as a single yarn, a core-sheath composite fiber in which a poorly soluble polyester resin is arranged in the core and a readily soluble polyester resin is arranged in the sheath.

3. A woven or knitted fabric comprising the polyester mixed fiber interlaced yarn according to claim 1 or 2.

4. A method for producing a polyester mixed fiber entangled yarn, comprising the following steps (a) and (b): (A) A step of false-twisting polyester yarn YA having a hot water shrinkage rate of 40% or more using a fluid swirl nozzle under conditions of a heater temperature of 260°C or more and a twist / untwist tension ratio of 0.8 to 1.2 to obtain polyester false-twist textured yarn FA having a hot water shrinkage rate of 5% or less. (b) A step of doubling the polyester false twist textured yarn FA with a polyester yarn YB having a hot water shrinkage rate of 15% or more, interlacing the yarn, and compounding the yarn.

Images