JP7762026B2 - Composite false twist blended yarn and woven/knitted fabric - Google Patents

Description

The present invention relates to composite false-twist blended yarns and woven and knitted fabrics made therefrom.

Composite false-twist textured yarns have traditionally been widely used in the clothing industry, and various proposals have been made to achieve a smooth texture and a natural, heathered appearance.

For example, a composite textured yarn has been proposed in which a false-twisted crimped multifilament yarn and a non-crimped multifilament yarn are used, and an air control valve that controls the injection of compressed air from an air tank is connected to the fluid treatment, and computer control is used to create composite textured yarn in which entanglement-concentrated areas and untangled areas alternate in the longitudinal direction of the composite textured yarn, and the lengths of these areas are random (see Patent Document 1).

In addition, to provide knitted fabrics with excellent snagging resistance without compromising soft texture or stretchability, low-torque, low-interlace processed yarns composed of two or more types of false-twisted crimped processed yarns have been proposed (see Patent Document 2).

Japanese Patent Application Laid-Open No. 2005-307382 Patent No. 5155162

However, in the composite false twist blended yarn proposed in Patent Document 1 above, in which entanglement-concentrated sections and non-entangled sections alternate in the longitudinal direction, entanglement-concentrated sections and short non-entangled sections alternate at approximately equal intervals. As a result, the cycle between the darkly dyed and lightly dyed sections relative to the yarn length after blending is short, resulting in a marbled appearance in the areas where entanglement is concentrated, and it was not possible to achieve a kasuri-style appearance with an excellent high-level gradation effect.

Furthermore, Patent Document 2 proposes an entangled yarn made up of two or more types of false-twisted crimped yarn and subjected to interlacing processing. However, the entanglement process (interlacing) is carried out using a normal interlacing nozzle, and entangled sections and short, unentangled sections alternate at approximately equal intervals. As a result, the cycle between darkly and lightly dyed sections relative to the length of the blended yarn becomes shorter, resulting in a marbled appearance in areas where the entanglement is concentrated, and it is not possible to achieve a kasuri-style appearance with an excellent, highly gradational effect.

The present invention aims to solve the above-mentioned problems by providing a composite false-twist blended yarn and woven/knitted fabrics that do not fade between the darkly and lightly dyed portions even after blending, and that, when used in woven/knitted fabrics and dyed, have a soft, smooth feel and excellent texture, as well as a kasuri-style appearance with an excellent gradation effect that could not be achieved with conventional false-twist blended yarns.

As a result of further investigations, the inventors discovered that by processing two types of thermoplastic multifilament yarns using a false-twist entanglement method that controls the entanglement spacing and entangles the yarns with a small number of entanglements, and using the resulting composite false-twist blended yarn in woven or knitted fabrics, it is possible to impart a handle and surface feel that could not be achieved with conventional blended yarns, thereby arriving at the present invention. Furthermore, in this invention, the inventors discovered that by weaving and knitting a specific thick and thin cationic dyeable polyester multifilament yarn and a thick and thin polyester side-by-side (polyethylene terephthalate) multifilament yarn, controlling the thick and thin patterns of the cationic dyeable polyester and the entanglement spacing, and dyeing the fabric with a cationic dye using a blended entanglement method with a low number of entanglements, it is possible to obtain blended yarns and woven or knitted fabrics that have a softer, smoother handle and a color that changes from dark to light over a long period, resulting in a more natural gradation effect when combined with the colors of polyester multifilament yarns with different dyeabilities.

The composite false twist blended yarn of the present invention is a composite false twist blended yarn composed of at least two types of thermoplastic multifilament yarn, has a false twist crimp overall, and among 30 spread portions, there are 1 to 15 spread portions with an entanglement interval of 1 mm or more and less than 25 mm, 1 to 15 spread portions with an entanglement interval of 25 mm or more and less than 50 mm, and 1 to 10 spread portions with an entanglement interval of 50 mm or more.

According to a preferred embodiment of the present invention, the thermoplastic multifilament yarn of the composite false twist blended yarn comprises cationic dyeable polyester multifilament yarn A and cationic non-dyeable multifilament yarn B, and contains 20% by mass or more and 80% by mass or less of the cationic dyeable polyester multifilament yarn A.

According to a preferred embodiment of the present invention, the composite false twist blended yarn is made of thermoplastic multifilament yarns, at least one of which has latent crimping properties.

According to a preferred embodiment of the present invention, the composite false twist blended yarn has at least two types of thermoplastic multifilament yarns each having uneven thickness in the fiber axis direction, with the thick portions of the yarns being out of phase with each other, and the yarn structure has a partially reversible yarn length difference, with the actual yarn length difference between the yarns being 3% or less.

According to a preferred embodiment of the present invention, the composite false twist blended yarn has an entanglement count of 2 or more and 45 or less entanglements under a load of 0.1 g/dtex, and an entanglement count of 0 or more and 30 or less entanglements under a load of 0.5 g/dtex.

The woven or knitted fabric of the present invention is a woven or knitted fabric made in part using the composite false twist blended yarn.

The woven or knitted fabric of the present invention also comprises, at least in part, a composite false twist blended yarn composed of at least two types of thermoplastic multifilament yarn, which has a false twist crimp overall, and in which, among 30 spread portions, there are 1 to 15 spread portions with an entanglement interval of 1 mm or more but less than 25 mm, 1 to 15 spread portions with an entanglement interval of 25 mm or more but less than 50 mm, and 1 to 10 spread portions with an entanglement interval of 50 mm or more.

According to a preferred embodiment of the present invention, the woven or knitted fabric is a woven or knitted fabric in which the number of entanglements of the composite false twist blended yarn is 1 or more per meter and 35 or less per meter.

The composite false-twist blended yarn of the present invention is composed of at least two types of thermoplastic multifilament yarn, has a false-twist crimp overall, and by controlling the interlaced and open portions, it is woven into a woven or knitted fabric. When dyed, it has a soft, smooth feel, an excellent texture, and a kasuri-style appearance with an excellent gradation effect, something that could not be achieved with conventional composite false-twist blended yarns.

FIG. 1 is a conceptual diagram for explaining one embodiment of a preferred method for producing a false-twisted blended yarn of the present invention. FIG. 2 is a conceptual diagram for explaining one embodiment of a preferred method for producing the false twisted blended yarn of the present invention. FIG. 3 is a conceptual diagram for explaining one embodiment of a preferred method for producing the false twisted blended yarn of the present invention. FIG. 4 is a photograph of the surface of the circular knitted fabric obtained in Example 2. FIG. 5 is a photograph, used as a drawing, of the surface of the circular knitted fabric obtained in Comparative Example 2.

The false twist blended yarn of the present invention is a composite false twist blended yarn composed of at least two types of thermoplastic multifilament yarn, has a false twist crimp overall, and when the entanglement spacing of 30 spread portions in the false twist blended yarn is measured, the number of spread portions with an entanglement spacing of 1 mm or more but less than 25 mm is 1 to 15, the number of spread portions with an entanglement spacing of 25 mm or more but less than 50 mm is 1 to 15, and the number of spread portions with an entanglement spacing of 50 mm or more is 1 to 10, so that the yarns are appropriately blended, and when woven or knitted into a woven or knitted fabric and dyed, a scraped appearance can be obtained.

If the number of spread parts with an entanglement interval of 1 mm or more and less than 25 mm, 25 mm or more and less than 50 mm, or 50 mm or more is less than 1, a scraped appearance can be obtained, but the fiber mixing ability decreases, and there are concerns about poor processability and poor quality during the production of woven or knitted fabrics. Furthermore, if the number of spread parts with an entanglement interval of 1 mm or more and less than 25 mm, 25 mm or more and less than 50 mm, or 50 mm or more exceeds 15, stable processability and quality can be obtained, but a marbled appearance occurs and a scraped appearance cannot be obtained. A more preferable number of spread parts is one or more and 10 or less spread parts with an entanglement interval of 1 mm or more and less than 25 mm, one or more and 10 or less spread parts, one or more and 10 or less spread parts, one or more and 10 or less spread parts, and one or more and 10 or less spread parts with an entanglement interval of 50 mm or more. To measure the lengths of 30 spread portions in the false twist blended yarn, one end of a randomly sampled textured yarn is fixed to a clamp and hung vertically, and an initial load (0.002 g/dtex) is applied to the other 1 m end and left to stand for 2 minutes. If the load touches the floor, it is excluded from the measurement. The intertwined points are confirmed visually and marks are placed at the centers of the intertwined points with a marker. The area sandwiched between adjacent intertwined points (marks) is considered to be the spread portion, and the length between the intertwined points is considered to be the intertwining spacing. The number of spread portions (pieces) and the length (mm) between the intertwined points are measured from the fixed end, and the intertwining spacing of the 30 spread portions is measured.

The false-twist blended yarn of the present invention is composed of at least two types of thermoplastic multifilament yarns. The thermoplastic multifilament yarns are thermoplastic synthetic fibers, which are generally classified as fibers.

As for at least two or more types of thermoplastic multifilament yarn, it is preferable to combine composite textured yarns of thermoplastic multifilaments with different dyeabilities, and it is preferable to use a fiber yarn dyeable with a cationic dye, such as a cationic dyeable polyester multifilament yarn, as one type. Other polymers that can be used for thermoplastic multifilament yarn include, for example, polyalkylene terephthalates such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, and polytrimethylene terephthalate; polyesters such as polylactic acid; polyolefins such as polypropylene; polymers such as polycarbonate, polyacrylate, polyamide, polylactic acid, polyurethane, and polyphenylene sulfide, as well as copolymers thereof.

In the above, "different dyeability" means that color differences emerge between fiber types when different types of fibers are dyed under dyeing conditions that dye at least one type of fiber. Furthermore, "cationic dye-dyable fiber yarn" refers to fiber yarn that can be dyed with cationic dyes (hereinafter, "cationic dye-dyable" may also be referred to as "cationic dyeable"). Thermoplastic multifilament yarns other than cationic dye-dyable fiber yarns may be referred to as other thermoplastic multifilament yarns or, for convenience, "cationic dye-non-dyable yarns," and "cationic dye-non-dyable" may also be referred to simply as "cationic non-dyable."

These thermoplastic multifilament yarn materials may contain various additives in the polymer, such as inorganic substances such as titanium oxide, silica, and barium oxide, colorants such as carbon black, dyes, and pigments, flame retardants, fluorescent brighteners, antioxidants, or ultraviolet absorbers.

The cross-sectional shape of the fiber can be a perfect circle, as well as a variety of other shapes, including flat, polygonal (triangle, square, hexagon, octagon, etc.), daruma (with uneven parts), Y-shaped, and star-shaped.

Preferred examples of polymers constituting the cationic dyeable polyester multifilament yarn include those typically used as cationic dyeable polyesters. Specifically, cationic dyeable polyethylene terephthalate, such as copolymerized polyethylene terephthalate, which is obtained by copolymerizing polyethylene terephthalate with an isophthalic acid component having a sulfonate group, can be used. A commonly used isophthalic acid component having a sulfonate group may be used. Specific examples include 5-sodium sulfoisophthalic acid, 5-sodium sulfoisophthalic acid dimethyl ester, 5-sodium sulfoisophthalic acid diethyl ester, 5-sodium sulfoisophthalic acid diglycol ester, 5-lithium sulfoisophthalic acid, 5-lithium sulfoisophthalic acid dimethyl ester, 5-lithium sulfoisophthalic acid diethyl ester, and 5-lithium sulfoisophthalic acid diglycol ester. Mixtures of these are also acceptable, but 5-sodium sulfoisophthalic acid dimethyl ester and 5-sodium sulfoisophthalic acid diglycol ester are preferred due to their improved dyeability and ease of availability.

The above-mentioned composite false twist blended yarn has a false twist crimp throughout, and is preferably a composite false twist blended yarn with a crimp configuration of 60% or more and 100% or less. A composite false twist blended yarn with a crimp configuration of 60% or more provides particularly excellent crimp properties, good processability during the production of woven or knitted fabrics, excellent quality, and a more desirable smooth feel. To measure the crimp configuration of the composite false twist blended yarn, a 30 cm length of composite false twist blended yarn is taken from the warp or weft direction of a woven or knitted fabric that has been dyed and finished, and a digital microscope VHX-500 (manufactured by Keyence Corporation) is used to apply a load of 1/30 g of the total fineness (D) to the polyester composite false twist blended yarn of the present invention and observe it from the side in the longitudinal direction of the polyester composite false twist blended yarn. All multifilaments are measured, and the number of all multifilaments is defined as A, and the number of multifilaments with crimps is defined as B, to define the false twist crimp percentage ((B÷A)×100(%)). When evaluating using a composite false twist mixed yarn, it is treated in hot water at 98°C for 30 minutes without applying a load, and one 30 cm sample is taken from the treated mixed yarn and evaluated. The reason for the hot water treatment here is that when the composite false twist mixed yarn contains fibers with latent crimping properties, the crimps become apparent during heat treatment in the process of manufacturing woven or knitted fabrics after knitting, weaving, dyeing, and finishing processes, and the product has crimps, so it is appropriate to treat it as a multifilament yarn with crimps. Therefore, the hot water treatment is performed as a simulation to make the crimps apparent, and this is evaluated as a multifilament yarn with crimps. In the present invention, the thermoplastic multifilament yarn preferably comprises a fiber yarn dyeable with a cationic dye and a fiber yarn that is not dyeable with a cationic dye. In particular, it preferably comprises a cationic dyeable polyester multifilament yarn A and a cationic non-dyeable multifilament yarn B.

The proportion of the cationic dyeable polyester multifilament yarn A in the composite false twist blended yarn is preferably 10% by mass or more and 90% by mass or less, and more preferably 20% by mass or more and 80% by mass or less. The preferred proportions of other cationic dyeable fiber yarns are the same as above.

If the proportion of cationic dye-dyeable fiber yarns is less than this, the cationic dye-dyeable fiber yarns will be hidden by the entangled mixed fibers, making it difficult to achieve a multicolor effect. Conversely, if the proportion of cationic dye-dyeable fiber yarns is greater than this, the cationic dye-undyeable fiber yarns will also be hidden by the entangled mixed fibers, making it difficult to achieve a multicolor effect. From the perspective of processability, a high proportion of cationic dye-dyeable fiber yarns is also undesirable, as the thermoplastic multifilament yarn is more likely to fluff and its strength decreases significantly as the proportion increases.

Similarly, when this method is applied to at least two types of thermoplastic multifilament yarns with different dyeabilities, the proportion of one type of thermoplastic multifilament yarn is preferably 10% by mass or more, and more preferably 20% by mass or more. The upper limit is preferably 90% by mass or less, and more preferably 80% by mass or less. This prevents the one type of thermoplastic multifilament yarn and the other type of thermoplastic multifilament yarn from being overly hidden by interlacing, resulting in a better gradation effect.

It is preferable that at least one of the thermoplastic multifilament yarns of the present invention has latent crimping properties. In composite false-twist blended yarns, the cationic non-dyeable multifilament yarn usually has the form of a multifilament and may be a fiber composed of a single component, i.e., a single fiber, or a conjugate fiber composed of two or more components. In the case of a conjugate fiber composed of two or more components, it is preferable that it is a conjugate fiber obtained by side-by-side conjugation. By using a conjugate fiber obtained by side-by-side conjugation, woven and knitted fabrics with excellent stretchability and stretch-back properties can be obtained due to the coil crimp of the conjugate fiber accompanying the false-twist crimp. The coil crimp is thought to occur due to the difference in internal strain between the two component polymers caused by drawing and heat after spinning, and crimp occurs when the conjugate fiber is exposed to heat in a relaxed state. It is preferable that the conjugate fiber obtained by side-by-side conjugation be made of two polyester polymers with different viscosities.

The polymer that constitutes the side-by-side conjugated fiber is preferably a polyester polymer, and the polyester polymer can be selected from polyethylene terephthalate, polymethylene terephthalate, or polybutylene terephthalate. Note that the two types of polyester polymers referred to here do not only refer to polymers with different polymer structures, but also to polymers of the same type but with different viscosities, which are understood to be different types.

Among these, conjugate fibers made from a side-by-side composite of polybutylene terephthalate and polyethylene terephthalate are preferred.

The at least two types of thermoplastic multifilament yarns used in the present invention are preferably crimped yarns with thickness variations in the fiber axis direction. While there are several methods for imparting thickness variations, considering the fact that false twisting also imparts crimp, using thick-and-thin processing is superior. The thick portions of thick-and-thin yarns are low-oriented and therefore readily absorb dyes, resulting in darker dyes. Conversely, the thin portions are highly oriented and therefore less readily absorb dyes, resulting in lighter colors. In other words, by imparting thickness variations to both the cationic dye-dyeable polyester fiber yarn and the cationic dye-undyeable polyester fiber yarn, it is possible to achieve a more multicolored and natural mottled look. While the mottled look achieved with thick-and-thin yarns depends on the processing conditions, it has relatively long, light-and-dark sections, making it easy to achieve a flowing mottled look, which is advantageous for more pronounced expression of the effects of the present invention. Furthermore, it is preferable that the phases of the thick portions of each yarn are shifted. "The phases of the thick parts are out of sync" means that the phases of the thick parts are irregular between each thread, and while there are extremely rare instances where they match, for the most part the phases of the thick parts are different. As we will explain later, by adopting this type of structure, we can expect to achieve a fluffy feel and further improve the flecked texture achieved by twisting the yarn.

In addition, in the composite false twist blended yarn of the present invention, the substantial difference in yarn length between the yarn ends is preferably 3% or less. The yarn length difference here is a value measured by the method described below. For example, in the case of a combination of a cationic dyeable fiber yarn and a cationic non-dyeable fiber yarn, the substantial difference in yarn length refers to the difference in the total length in the fiber axis direction between the cationic dyeable fiber yarn and the cationic non-dyeable fiber yarn. In the case of a core-sheath structure, a larger yarn length difference is advantageous for achieving a fluffy feel. However, the composite false twist blended yarn of the present invention has a sufficient fluffy feel even when the yarn length difference is substantially 3% or less. Furthermore, if at least two types of thermoplastic multifilament yarns have uneven thickness in the fiber axis direction, it is preferable that the resulting voids are offset in phase between the thick portions of each yarn and that the thick portions of each filament are largely in phase with each other. This results in an even more excellent fluffy feel. The thick portion (thick portion) of each yarn is an incompletely stretched portion, which is less oriented than the stretched portion and has a high elongation. Conversely, the thin portion (thin portion) is a fully stretched portion, which is highly oriented and has a relatively low elongation. Therefore, the highly oriented thin portion acts like a core yarn, and the low oriented thick portion acts like a sheath yarn. This occurs in both the cationic dye-dyeable fiber yarn and the cationic dye-undyeable fiber yarn, resulting in a partial core-sheath structure between the yarns, which forms a random structure with a partially reversible yarn length difference that is reversed in each portion, resulting in a particularly excellent fluffy feel. Here, partially reversible yarn length difference means that in the portions where the thick portion and thin portion of each yarn are aligned, the yarn on the thick portion side is longer, resulting in a yarn length difference in this portion. Conversely, when the thick portion and thin portion are reversed, the yarn becomes longer in the opposite direction. In other words, this means that there are yarn length differences in each portion, and that these yarn length differences are reversible, with some portions becoming core yarns and others becoming sheath yarns. Similarly, when using a combination of thermoplastic multifilament yarns other than the above-mentioned cationic dye-dyeable fiber yarns, it is preferable to keep the yarn length differences between the yarns contained in the composite false twist blended yarn of the present invention within an appropriate range. This is advantageous in that it effectively suppresses the occurrence of a fluffy feel, neps due to ironing, and heather defects due to yarn slippage.

When dyed, the composite false-twist blended yarn of the present invention has a relatively darkly dyed portion and a relatively lightly dyed portion that do not fade. Furthermore, when used in woven or knitted fabrics, it provides a soft, smooth, and excellent texture. As a result, it is preferable to obtain a kasuri-style appearance with an excellent gradation effect. Furthermore, by using two or more types of thermoplastic multifilament yarn with different dyeabilities, such as cationic dyeable fiber yarn and cationic non-dyeable fiber yarn, to produce a composite false-twist blended yarn, knitting, weaving, and dyeing it, it is even more preferable to obtain an even more excellent gradation effect and a natural kasuri-style appearance.

Therefore, in the present invention, it is preferable to use false-twisted blended yarn in at least a portion of the woven or knitted fabric. It is particularly preferable to use false-twisted blended yarn in all of the warp and/or weft yarns that make up the woven fabric, or in all of the knitting yarns that make up the knitted fabric, in order to achieve an excellent gradation effect. It is also preferable to use it in combination with other fibers to achieve the desired design. When used in combination with other fibers, it is preferable that the composite false-twisted blended yarn contain 60% or more by mass.

There are no particular restrictions on the weave that makes up the above-mentioned woven or knitted fabrics. In the case of woven fabrics, the weave may be any of plain weave, twill weave, satin weave, or variations thereof, depending on the intended use. In the case of knitted fabrics, the weave may be any of circular knit jersey weave, interlock weave, smooth weave, warp knit half weave, satin weave, jacquard weave, or variations thereof, depending on the intended use.

Woven and knitted fabrics made using the false-twist blended yarn of the present invention can be subjected to a variety of processes, from weight reduction and other processes aimed at adjusting texture, to physical processes such as nap raising and calendaring, and functional processes such as water-repellent, water-absorbent, and antistatic.

The number of entanglements in the composite false twist blended yarn contained in the woven or knitted fabric of the present invention is preferably 1 or more/m to 35 or less/m, and more preferably 5 or more/m to 15 or less/m. The number of entanglements referred to here is the number of entanglements measured by the method described below in "Number of entanglements in separated yarns."

Furthermore, when the entanglement spacing of 30 spread portions in the composite false twist mixed yarn contained in the woven or knitted fabric of the present invention is measured, it is preferable that the number of spread portions having an entanglement spacing of 1 mm or more and less than 25 mm is 1 to 15, the number of spread portions having an entanglement spacing of 25 mm or more and less than 50 mm is 1 to 15, and the number of spread portions having an entanglement spacing of 50 mm or more is 1 to 10; it is more preferable that the number of spread portions having an entanglement spacing of 1 mm or more and less than 25 mm is 1 to 10, the number of spread portions having an entanglement spacing of 25 mm or more and less than 50 mm is 1 to 10, and the number of spread portions having an entanglement spacing of 50 mm or more is 1 to 10. The number of spread portions and entanglement spacing referred to here are values measured by the methods described below in "Number of spread portions and entanglement spacing of resolved yarns."

Next, we will explain the method for producing the composite false twist blended yarn of the present invention.

The present invention relates to a composite false-twist blended yarn composed of at least two types of thermoplastic multifilament yarn. The method for producing the composite false-twist blended yarn comprises separately drawing two or more thermoplastic synthetic multifilament highly oriented undrawn yarns, each of which serves as the raw yarn, in a heating device at a temperature not exceeding the glass transition temperature of each highly oriented undrawn yarn plus 50°C, followed by a false-twisting process and an entanglement process at a draw ratio of 1.1 or more in a single false-twisting process. As before, this description will be given using, as examples, a polyethylene terephthalate fiber yarn dyeable with cationic dyes and a polyethylene terephthalate fiber yarn that is undyable (non-dyeable) to cationic dyes but dyeable with disperse dyes. The highly oriented undrawn polyethylene terephthalate yarn dyeable with cationic dyes and the highly oriented undrawn polyethylene terephthalate yarn undyable to cationic dyes are separately drawn in a heating device at a temperature not exceeding the glass transition temperature of each highly oriented undrawn yarn plus 50°C. The highly oriented undrawn polyethylene terephthalate yarn referred to here has a spinning speed of 2000 to 4500 m/min and a birefringence index Δn in the range of 0.015 to 0.080. In the present invention, these yarns are drawn separately, allowing for the selection of a draw ratio appropriate for each yarn quality, enabling a wide variety of combinations. However, if the yarns are drawn parallel to one another and then drawn, the processing conditions must be adjusted to match the high-speed yarn. Differences in spinning speeds can lead to differences in yarn length, which can lead to concerns about the occurrence of neps due to loosening or ironing. Furthermore, drawing at a temperature below the glass transition point + 50°C is preferred, as this results in particularly pronounced figuredness. The drawing temperatures may also be different for each yarn. The drawn yarns are then combined in the false twist section, but the combined yarns may be drawn parallel to one another using rollers before the false twist section.

The draw ratio for the draw-twisting process is preferably 1.1 times or more, and more preferably 1.1 times or more and 1.9 times or less.

When performing thick and thin false twist processing, the draw ratio is preferably 1.1 times or more, and more preferably 1.1 times or more and 1.3 times or less. A draw ratio of 1.1 times or more is preferable because the processing is stable regardless of the yarn speed and yarn breakage is suppressed. A draw ratio of 1.3 times or less is preferable because the thick part is maintained in a good state by drawing and a particularly excellent figured grain is obtained.

The false twisting device may be a pin type, a three-axis external friction type, or a belt nip type, but the three-axis external friction type or belt nip type is preferred as it allows for high-speed processing. It is also necessary to impart entanglement to converge the two yarn strands.

With regard to the composite false-twist blended yarn of the present invention, entanglement during false-twist blending significantly affects the texture of the woven or knitted fabric. Commonly known entanglement blending methods used in the false-twist blending process include the Taslan blending method using a turbulent nozzle and the interlace blending method using an interlace nozzle. In the Taslan blending method using a turbulent nozzle, turbulence is generated within the nozzle, causing excessive supply of slack yarns, which individually impart a turning force to the slack yarns, causing them to entangle with neighboring yarns and create fine loops. Therefore, even when Taslan blending is performed using at least two types of thermoplastic multifilament yarns in the fiber axis direction, the entire yarns become entangled, creating fine loops, and the desired kasuri-like appearance cannot be achieved. Furthermore, in the interlace blending method using an interlace nozzle, a jet is applied from a single direction transverse to the running yarn, causing the running yarn to exhibit chord-like vibration behavior as it passes through the interlace nozzle. As the yarn crosses the jet, it opens up and the single yarns behave randomly, resulting in entanglement at both ends. Because the string vibrates at a constant frequency, the lengths of the spread and entangled portions do not change significantly, resulting in a shorter length. Since the entangled portions are formed when single yarns become entangled and converge, even if interlaced fibers are mixed using at least two types of thermoplastic multifilament yarn in the fiber axis direction, the entangled portions will be short in length, making it impossible to achieve the desired kasuri-style appearance.

In other words, conventional blending methods cannot achieve a kasuri-style appearance with an excellent gradation effect. The nozzle used for the composite false-twist blended yarn of this invention operates on a different blending principle than the nozzle used in the blending method described above. Jets are applied to two types of traveling yarn from two different directions and sent out to the nozzle outlet. A guide is attached to the nozzle outlet to suddenly change the direction of the yarn. As the yarn escapes the propulsion fluid, the fluid passes by the sides of the slackened yarn and entangles the single yarns, resulting in mild entanglement. Unlike a turbulent nozzle, which applies a high-pressure jet to the nozzle space, which only has a gap from which the yarn can escape, a low-pressure jet used in an interlace nozzle is applied, resulting in mild entanglement.

To obtain such a lightly entangled composite false twist blended yarn, it is preferable to use the nozzle described above (hereinafter referred to as a "special interlace nozzle"). For example, a nozzle such as the KF-JET manufactured by Heberlein is preferable.

When blending at least two types of thermoplastic multifilament yarns, the pressure of the special interlace nozzle jet is preferably 0.1 MPa or more and 0.3 MPa or less. If the pressure is less than 0.1 MPa, the desired blending of the at least two types of thermoplastic multifilament yarns will not be achieved, resulting in reduced blending, which may lead to separation of the two yarns or yarn breakage in subsequent processes, resulting in a lower quality woven or knitted fabric. If the pressure exceeds 0.3 MPa, sufficient blending will be achieved, but the at least two types of thermoplastic multifilament yarns will become strongly entangled, resulting in a finer grained texture in the resulting woven or knitted fabric. A more preferred range is 0.15 MPa or more and 0.25 MPa or less.

Furthermore, when mixing at least two types of thermoplastic multifilament yarns, the feed rate between each yarn and the special interlace nozzle is preferably 0.5% or more and 4.0% or less. If it is less than 0.5%, the desired mixing of at least two types of thermoplastic multifilament yarns will not be achieved, resulting in a decrease in mixing ability, which may lead to separation of the two yarns in subsequent processes or yarn breakage, resulting in a decrease in the quality of the resulting woven or knitted fabric. If it exceeds 4.0%, the feed rate will be too high relative to the nozzle jet, causing the at least two types of thermoplastic multifilament yarns to slacken before and after the nozzle, resulting in flapping, leading to yarn breakage and friction with the guides before and after the nozzle, causing nozzle and guide contamination. A more preferred range is 0.8% or more and 3.0% or less.

The twist direction of the false-twist composite blended yarn may be either the S direction or the Z direction, but the SZ direction is preferred to improve the grain quality of the woven or knitted fabric.

The composite false twist blended yarn with the above-mentioned slight entanglement is a preferred embodiment because it more significantly exhibits the effects of the present invention. Because the entanglement is slight, applying a certain amount of load will cause some of the entanglement to come undone.

The number of entanglements in the composite false twist blended yarn of the present invention is preferably 2 to 45 entanglements/m under a load of 0.1 g/dtex, and 0 to 30 entanglements/m under a load of 0.5 g/dtex. It is particularly preferred that the number of entanglements under a load of 0.1 g/dtex is 10 to 30 entanglements/m, and 0 to 20 entanglements/m under a load of 0.5 g/dtex.

[Fineness of highly oriented undrawn yarn and composite false-twisted blended yarn]
The yarn is wound 80 times on a measuring machine (circumference 1.125 m) to form a ring, and the weight is measured to four decimal places on a balance. This process is repeated 10 times, and the average of the 10 weights is taken as P, and the yarn fineness is calculated using the following formula.
Yarn fineness (dtex) = P × 100 × 1.11

[Tensile strength and elongation of composite false-twist blended yarn]
Measurement was carried out in accordance with JIS L1013 Chemical Fiber Filament Yarn Testing Method (2010).

The grip distance was 200 mm, the pulling speed was 200 mm/min, and a load-elongation curve was obtained using a tensile tester (Shimadzu Corporation). The load value at break was divided by the initial fineness to obtain the strength, and the elongation at break was divided by the initial sample length to obtain the elongation.

[Hot water shrinkage rate]
The yarn is wound 10 times on a measuring machine (circumference 1.125 m) to form a ring, and a load of 1/30 g per d (1.11 dtex) is applied to determine the length X. The yarn is then immersed in boiling water in a free state for 30 minutes and then naturally dried, and a load of 1/30 g per d (1.11 dtex) is again applied to determine the length Y, which is calculated using the following formula. When measuring the fineness of a thermoplastic multifilament yarn, the two yarns are wound separately before being mixed, and the measurement is carried out using the wound yarn.
Hot water shrinkage (%) = [(X-Y)/X] x 100

[Difference in yarn length between original yarns of composite false-twist blended yarn (heat treatment)]
Randomly sampled composite false-twisted mixed yarns were wound 10 times on a measuring machine (circumference 1.125 m) to form a ring, and treated in 98°C hot water for 30 minutes without applying a load. 20 mixed yarns were sampled at regular intervals (5 cm based on the original yarn) from the treated mixed yarn. The sampled mixed yarns were disassembled and separated into single yarns of cationic dyeable polyester multifilament yarn A and cationic non-dyeable multifilament yarn B. The disassembled yarns were placed on a glass plate, a small amount of glycerin was dripped on it, and an initial load was applied to the other end to stretch the yarn so as not to bend, and the yarn length was measured. The average length of 20 single yarns of cationic dyeable polyester multifilament yarn A was designated L5, and the average length of 20 single yarns of cationic non-dyeable multifilament yarn B was designated L6, and the yarn length difference was calculated using the following formula. When a thermoplastic multifilament yarn other than those mentioned above is used, the yarn length difference is calculated by setting the yarn length of the yarn dyed as the base color (the color most frequently used on the front side) as L5 and the yarn length of the other yarn as L6.
Thread length difference (%) = [(L5-L6)/L6] x 100
Initial load: 0.002g/dtex

[Number of entanglements in composite false twist blended yarn]
One end of a randomly sampled composite false twist blended yarn is fixed to a clamp 1.7 m above the floor and hung vertically, and an initial load is applied to the other 1.5 m end, and the yarn is left to stand for 2 minutes. The initial load is removed, and a load of 0.1 g/dtex or 0.5 g/dtex is attached and the yarn is left to stand for 2 minutes. If the load touches the floor, the yarn is excluded from the measurement. Intertwining points are confirmed visually, and the centers of the intertwining points are marked with a marker. The number of intertwining points within 1 m from the fixed end is counted and used as the number of intertwining points.
Initial load: 0.002g/dtex

[Number of open fibers and entanglement intervals of composite false twist blended yarn]
One end of a randomly sampled composite false twist blended yarn was fixed to a clamp 1.2 m above the floor and hung vertically, and an initial load was applied to the other 1 m end, which was left to stand for 2 minutes. If the load touched the floor, the yarn was excluded from the measurement. The entangled points were confirmed visually, and the centers of the entangled points were marked with a marker. The number (pieces) of spread portions and the length (mm) between the entangled points were measured from the fixed end, and the entanglement spacing of 30 spread portions was measured. This operation was repeated 10 times, and the average number of entanglement spacings for the 10 times was calculated.
Initial load: 0.002g/dtex

[Number of intertwining decomposition threads]
One end of the untwisted composite false twist blended yarn randomly collected from the woven/knitted fabric is fixed to a clamp 1.7 m above the floor and hung vertically, and an initial load is applied to the other 1.5 m end and left to stand for 2 minutes. If the load touches the floor, it is excluded from the measurement. The intertwined points are visually confirmed and the centers of the intertwined points are marked with a marker. The number of intertwined points within 1 m from the fixed end is counted and taken as the number of intertwined points. The load applied during untwisting/knitting is 0.3 g/detx.
Initial load: 0.002g/dtex
If the specified amount of sample cannot be collected, repeat the measurement until the total length reaches 1 m.

[Number of opened parts of decomposed yarns, intertwining interval]
One end of an untwisted composite false twist blended yarn randomly collected from a woven or knitted fabric is fixed to a clamp 1.2 m above the floor and hung vertically, and an initial load is applied to the other 1 m end, which is left to stand for 2 minutes. If the load touches the floor, it is excluded from the measurement. The entangled points are confirmed visually, and the centers of the entangled points are marked with a marker. The number of spread portions (pieces) and the length (mm) between the entangled points are measured from the fixed end, and the entanglement spacing of 30 spread portions is measured. This operation is repeated 10 times, and the average number of entanglement spacings for the 10 times is calculated. The applied load during untwisting is 0.3 g/detx.
Initial load: 0.002g/dtex
If the specified amount of samples cannot be collected, the measurement is repeated until a total of 30 spread portions are found.

[Degree of grain]
The degree of the figured feel of the fabric was visually evaluated by 10 skilled experts using the following three-level rating system: Excellent, Good: Pass.
◎: Has a scraped grain texture and a strong gradation effect.
Good: Has a kasuri-style grained texture and a gradation effect.
×: Has a marbling-like grained texture and a weak gradation effect.

[Texture]:
The softness was evaluated by 10 experts using the following four-level rating system: Excellent and Good were considered acceptable.
◎: A texture that feels particularly soft when touched with the hand.
○: Feels soft when touched with the hand.
△: A texture that feels slightly soft when touched with the hand.
×: Texture that does not feel soft when touched with the hand.

[Example 1]
A 90 decitex, 36 filament, cationic dyeable, highly oriented, undrawn polyester multifilament yarn (birefringence index Δn: 0.018) (made of cationic dyeable polyethylene terephthalate copolymer) (raw yarn A) produced at a spinning speed of 2100 m/min and a 90 decitex, 48 filament, highly oriented, undrawn polyester multifilament yarn (birefringence index Δn: 0.036) (made of cationic non-dyeable polyethylene terephthalate) (raw yarn B) produced at a spinning speed of 2500 m/min were false-twisted according to the production process shown in Figure 1 under the conditions shown in Table 1, and each yarn (the yarn derived from yarn A is referred to as yarn A, and the yarn derived from yarn B is referred to as yarn B) was subjected to an entanglement/mixing process using a special interlace nozzle (KF-JET manufactured by Heberlein) to obtain a composite false-twisted mixed yarn.

Figure 1 is a conceptual diagram showing one example of a preferred method for producing a composite false-twisted mixed yarn of the present invention. First, cationic dyeable polyester multifilament highly oriented undrawn yarn 1, which will become yarn A, passes through guide 2, is fed by first feed roller 3, passes through first heater 4, and is drawn and false-twisted and heat-set between the first false twisting device 5 and third feed roller 6. Polyester multifilament highly oriented undrawn yarn 11, which will become yarn B, is similarly processed, passes through guide 12, is fed by second feed roller 13, passes through first heater 4, and is drawn and false-twisted and heat-set between the first false twisting device 5 and third feed roller 6. The two processed yarns are false-twisted, fed to entanglement nozzle 7, and then entangled and mixed. After that, they are fed as composite false-twisted mixed yarn 9 by fourth feed roller 8 and taken up on take-up roller 10.

The number of entanglements under a load of 0.1 g/dtex in the obtained composite false twist blended yarn was 42/m, and the number of entanglements under a load of 0.5 g/dtex was 25/m. Of the 30 spread portions, 15 had an entanglement interval of 1 mm or more but less than 25 mm, 10 had an entanglement interval of 25 mm or more but less than 50 mm, and 5 had an entanglement interval of 50 mm or more. The tensile strength was 2.13 cN/dtex, the elongation was 23.8%, the total fineness was 112.6 dtex, the hot water shrinkage rate was 5.8%, and the yarn length difference was 2.3%. The crimp configuration of the obtained composite false twist blended yarn was 100%, and the yarn had false twist crimps overall.

Using the resulting composite false twist blended yarn as the warp and weft, a plain woven fabric was produced with a warp density of 82 threads/2.54 cm and a weft density of 72 threads/2.54 cm. The resulting fabric was then subjected to a liquid flow relaxation treatment according to a conventional method, followed by drying and intermediate setting. The intermediate setting was performed at a temperature of 170°C. The resulting fabric was then dyed using the cationic dye Cation Blue GRLH 200% at a temperature of 100°C for 30 minutes and subjected to a finish setting according to a conventional method. The finish setting was performed at a temperature of 160°C. The number of entanglements of the resolved yarns in the resulting fabric was 31/m, and of 30 spread portions, 15 had an entanglement spacing of 1 mm or more but less than 25 mm, 10 had an entanglement spacing of 25 mm or more but less than 50 mm, and 5 had an entanglement spacing of 50 mm or more. The heathered texture was evaluated using the same method as in Example 1, and the result was that the resulting plain weave fabric had a kasuri-style heathered texture with a surface texture that had a strong gradation effect, achieving the desired heathered texture.

[Example 2]
A 90 decitex 72 filament cation-dyeable polyester multifilament highly oriented undrawn yarn (birefringence index Δn: 0.017) (made of cation-dyeable polyethylene terephthalate copolymer) (raw yarn A) produced at a spinning speed of 2100 m/min and a 90 decitex 48 filament polyester multifilament highly oriented undrawn yarn (birefringence index Δn: 0.042) (cation-undyeable polyester side-by-side (polybutylene terephthalate/polyethylene terephthalate) multifilament highly oriented undrawn yarn) (raw yarn B) produced at a spinning speed of 3300 m/min were false-twisted to impart thick-thin variations under the conditions shown in Table 1 according to the production process shown in Figure 2, and each yarn (the yarn derived from yarn A is referred to as yarn A, and the yarn derived from yarn B is referred to as yarn B) was subjected to an entanglement/mixing process using a special interlace nozzle (KF-JET manufactured by Heberlein) to obtain a composite false-twisted mixed yarn.

Figure 2 is a conceptual diagram showing an example of a preferred method for producing the composite false-twist blended yarn of the present invention. First, cationic dyeable polyester multifilament highly oriented undrawn yarn 1 (raw yarn A), which becomes yarn A, passes through guide 2 and is fed by first feed roller 3. It is drawn between first heat pin 101 and third feed roller 102 to form thick and thin patterns, passes through first heater 4, and is draw-false-twisted and heat-set between first false twisting device 5 and fifth feed roller 103. Polyester multifilament highly oriented undrawn yarn 11 (raw yarn B), which becomes yarn B, is similarly processed, passes through guide 12 and is fed by second feed roller 13. It is drawn between second heat pin 105 and fourth feed roller 106 to form thick and thin patterns, passes through first heater 4, and is draw-false-twisted and heat-set between first false twisting device 5 and fifth feed roller 103. The two processed yarns are false-twisted and then fed to the entanglement nozzle 7, where they are entangled and mixed, and then sent out by the sixth feed roller 104 as a composite false-twisted mixed yarn 9, which is then wound around the take-up roller 10.

The number of entanglements under a load of 0.1 g/dtex for the obtained composite false twist blended yarn was 27/m, and the number of entanglements under a load of 0.5 g/dtex was 13/m. Of the 30 spread portions, 12 had an entanglement spacing of 1 mm or more but less than 25 mm, 10 had an entanglement spacing of 25 mm or more but less than 50 mm, and 8 had an entanglement spacing of 50 mm or more. The tensile strength was 2.01 cN/dtex, the elongation was 25.6%, the total fineness was 110.3 dtex, the hot water shrinkage rate was 4.8%, and the yarn length difference was 2.5%. The crimp structure of the obtained composite false twist blended yarn was 100%, and the yarn had false twist crimps overall.

The resulting composite false twist blended yarn was used at a blending ratio of 100% to produce a plain knit circular knit fabric using a 28G circular knitting machine with 42 wales/2.54 cm and 73 courses/2.54 cm.

The resulting circular knit fabric was then subjected to a liquid flow relaxation treatment according to a conventional method, followed by drying and intermediate setting. The intermediate setting was performed at a temperature of 170°C. The resulting circular knit fabric was then dyed using the cationic dye Cation Blue GRLH 200% at 100°C for 30 minutes and dried according to a conventional method. The number of entanglements of the decomposed yarns in the resulting knitted fabric was 18/m. Of the 30 spread portions, 12 had an entanglement spacing of 1 mm or more but less than 25 mm, 11 had an entanglement spacing of 25 mm or more but less than 50 mm, and 9 had an entanglement spacing of 50 mm or more. The resulting circular knit fabric had a kasuri-style heathered texture and a surface texture with a gradation effect, achieving the desired heathered texture. Figure 4 is a photograph showing the surface of the circular knit fabric. As shown in Figure 4, three colors are obtained: two colors due to the shades of dye in the cationic dyed thread A and one undyed color in thread B. Furthermore, by appropriately controlling the entanglement spacing between threads A and B, a unique kasuri-style grain is obtained, and the three colors appear to transition in a gradation.

[Example 3]
A 56 decitex, 36 filament, cationic dyeable polyester multifilament, highly oriented, undrawn yarn (birefringence index Δn: 0.016) (made of cationic dyeable polyethylene terephthalate copolymer) (raw yarn A) produced at a spinning speed of 2100 m/min, and a 90 decitex, 48 filament, polyester multifilament, highly oriented, undrawn yarn (birefringence index Δn: 0.042) (cationic non-dyeable polyester side-by-side (polybutylene terephthalate/polyethylene terephthalate) multifilament, highly oriented, undrawn yarn) (raw yarn B) produced at a spinning speed of 3300 m/min were false-twisted according to the production process shown in Figure 3 under the conditions shown in Table 1, and each yarn (the yarn derived from yarn A is referred to as yarn A, and the yarn derived from yarn B is referred to as yarn B) was subjected to an entanglement/mixing process using a special interlace nozzle (KF-JET manufactured by Heberlein) to obtain a composite false-twisted mixed yarn.

Figure 3 is a conceptual diagram showing an example of a preferred method for producing a composite false-twisted mixed yarn of the present invention. First, cationic dyeable polyester multifilament highly oriented undrawn yarn 1 (raw yarn A), which will become yarn A, passes through guide 2, is fed by first feed roller 3, passes through first heater 4, and is draw-false-twisted and heat-set between the first false twisting device 5 and third feed roller 201. The first false twisting device 5 undergoes an S-false-twist treatment. The polyester multifilament highly oriented undrawn yarn 11 (raw yarn B), which will become yarn B, is similarly processed, passes through guide 12, is fed by second feed roller 13, passes through second heater 203, and is draw-false-twisted and heat-set between the second false twisting device 204 and fourth feed roller 205. The second false twisting device 204 undergoes a Z-false-twist treatment. The two processed yarns are supplied to an entanglement nozzle 7, where they are entangled and mixed, and then fed by fifth feed roller 202 as composite false-twisted mixed yarn 9, which is then taken up by take-up roller 10.

The number of entanglements under a load of 0.1 g/dtex for the obtained composite false twist blended yarn was 14/m, and the number of entanglements under a load of 0.5 g/dtex was 6/m. Of the 30 spread portions, 10 had an entanglement spacing of 1 mm or more but less than 25 mm, 10 had an entanglement spacing of 25 mm or more but less than 50 mm, and 10 had an entanglement spacing of 50 mm or more. The tensile strength was 2.11 cN/dtex, the elongation was 22.6%, the total fineness was 89.4 dtex, the hot water shrinkage rate was 5.2%, and the yarn length difference was 2.8%. The crimp structure of the obtained composite false twist blended yarn was 100%, and the yarn had false twist crimps overall.

The resulting composite false twist blended yarn was used at a blending ratio of 100% to produce a plain knit circular knit fabric using a 28G circular knitting machine with 48 wales/2.54 cm and 75 courses/2.54 cm.

The resulting circular knit fabric was then subjected to a liquid flow relaxation treatment according to a conventional method, followed by drying and intermediate setting. The intermediate setting conditions were a temperature of 170°C. The resulting circular knit fabric was then dyed using cationic dye Cation Blue GRLH 200% at 100°C for 30 minutes and dried according to a conventional method. The number of entanglements in the resolved yarns of the resulting knitted fabric was 10/m, and of 30 spread portions, 11 had an entanglement spacing of 1 mm or more but less than 25 mm, 9 had an entanglement spacing of 25 mm or more but less than 50 mm, and 10 had an entanglement spacing of 50 mm or more. The resulting circular knit fabric had a kasuri-style heathered texture and a surface texture with a gradation effect, achieving the desired heathered texture.

[Comparative Example 1]
A 90 decitex, 36 filament, cationic dyeable, highly oriented, undrawn polyester multifilament yarn (birefringence index Δn: 0.018) (made of cationic dyeable polyethylene terephthalate copolymer) (raw yarn A) produced at a spinning speed of 2100 m/min and a 90 decitex, 48 filament, highly oriented, undrawn polyester multifilament yarn (birefringence index Δn: 0.036) (made of cationic non-dyeable polyethylene terephthalate) (raw yarn B) produced at a spinning speed of 2500 m/min were false-twisted according to the production process shown in Figure 1 under the conditions shown in Table 1, and each yarn (the yarn derived from yarn A is referred to as yarn A, and the yarn derived from yarn B is referred to as yarn B) was subjected to an entangled, mixed yarn process using an interlace nozzle to obtain a composite false-twisted, mixed yarn.

The interlace nozzle used was a conventional interlace nozzle in which a jet of air was blown from one direction transverse to the running direction of the yarn, so that the yarn crossed the jet.

The number of entanglements under a load of 0.1 g/dtex for the obtained composite false twist blended yarn was 105/m, and the number of entanglements under a load of 0.5 g/dtex was 103/m. Of the 30 spread portions, 30 spread portions had an entanglement spacing of 1 mm or more and less than 25 mm, 0 spread portions had an entanglement spacing of 25 mm or more and less than 50 mm, and 0 spread portions had an entanglement spacing of 50 mm or more. The tensile strength was 2.16 cN/dtex, the elongation was 23.4%, the total fineness was 113.2 dtex, the hot water shrinkage rate was 5.6%, and the yarn length difference was 2.3%. The crimp configuration of the obtained composite false twist blended yarn was 100%, and the yarn had false twist crimps overall.

A plain woven fabric was produced using the resulting blended yarn for the warp and weft, with a warp density of 82 threads/2.54 cm and a weft density of 72 threads/2.54 cm. The fabric was processed under the same conditions as in Example 1 and evaluated for its heathered texture by the same method as in Example 1. The number of entanglements in the resolved yarns of the resulting fabric was 104 threads/m, and of 30 spread portions, 30 had an entanglement spacing of 1 mm or more but less than 25 mm, 0 had an entanglement spacing of 25 mm or more but less than 50 mm, and 0 had an entanglement spacing of 50 mm or more. The resulting plain woven fabric had a marbled heathered texture and a surface texture with a weak gradation effect, and the desired heathered texture was not achieved.

[Comparative Example 2]
A 90 decitex 72 filament cation-dyeable polyester multifilament highly oriented undrawn yarn (birefringence index Δn: 0.017) (made of cation-dyeable polyethylene terephthalate copolymer) (raw yarn A) produced at a spinning speed of 2100 m/min and a 90 decitex 48 filament polyester multifilament highly oriented undrawn yarn (birefringence index Δn: 0.042) (cation-undyeable polyester side-by-side (polybutylene terephthalate/polyethylene terephthalate) multifilament highly oriented undrawn yarn) (raw yarn B) produced at a spinning speed of 3300 m/min were false-twisted to impart thick-thin variations under the conditions shown in Table 1 according to the production process shown in Figure 2, and each yarn (the yarn derived from yarn A is referred to as yarn A, and the yarn derived from yarn B is referred to as yarn B) was subjected to an entangled mixed fiber processing using the same interlace nozzle as used in Comparative Example 1, to obtain a composite false-twisted mixed yarn.

The number of entanglements under a load of 0.1 g/dtex for the obtained composite false twist blended yarn was 101/m, and the number of entanglements under a load of 0.5 g/dtex was 100/m. Of the 30 spread portions, 30 had an entanglement spacing of 1 mm or more but less than 25 mm, 0 had an entanglement spacing of 25 mm or more but less than 50 mm, and 0 had an entanglement spacing of 50 mm or more. The tensile strength was 2.04 cN/dtex, the elongation was 25.9%, the total fineness was 110.6 dtex, the hot water shrinkage rate was 4.7%, and the yarn length difference was 2.3%. The crimp configuration of the obtained composite false twist blended yarn was 100%, and the yarn had false twist crimps overall.

A plain knit circular knit fabric was made using the resulting composite false twist blended yarn at a blending ratio of 100% using a 28G circular knitting machine with 42 wales/2.54 cm and 73 courses/2.54 cm. The fabric was processed under the same conditions as in Example 2 and evaluated for heathered texture using the same method as in Example 1. The number of entanglements in the decomposed yarns of the resulting knit fabric was 100/m, and of 30 spread portions, 30 had an entanglement spacing of 1 mm or more but less than 25 mm, 0 had an entanglement spacing of 25 mm or more but less than 50 mm, and 0 had an entanglement spacing of 50 mm or more. The resulting circular knit fabric had a marbled heathered texture with a weak gradation effect on the surface, and the desired heathered texture was not achieved. Figure 5 is a photograph showing the surface of the circular knit fabric. As shown in Figure 5, three colors are obtained: two colors resulting from the shades of dye in the cationic dyed yarn A and one undyed color in yarn B. However, because the entanglement spacing between yarns A and B is not properly controlled, the transition between shades is short, resulting in a marbled, mottled texture, and the unique kasuri-style mottled texture targeted in this invention is not achieved.

[Comparative Example 3]
A 56 decitex, 36 filament, cationic dyeable polyester multifilament, highly oriented, undrawn yarn (birefringence index Δn: 0.016) (made of cationic dyeable polyethylene terephthalate copolymer) (raw yarn A) produced at a spinning speed of 2100 m/min and a 90 decitex, 48 filament, highly oriented, undrawn polyester multifilament yarn (birefringence index Δn: 0.042) (cationic non-dyeable polyester side-by-side (polyethylene terephthalate) multifilament, highly oriented, undrawn yarn) (raw yarn B) produced at a spinning speed of 3300 m/min were false-twisted according to the production process shown in Figure 3 under the conditions shown in Table 1, and each yarn (the yarn derived from yarn A is referred to as yarn A, and the yarn derived from yarn B is referred to as yarn B) was mixed using a Taslan nozzle to obtain a composite false-twisted mixed yarn.

The resulting composite false-twisted blended yarn was entangled throughout the yarn using a Taslan nozzle, forming fine loops, making it impossible to measure the number of entanglements, number of spreads, and intertwining spacing. The tensile strength was 2.02 cN/dtex, the elongation was 22.1%, the total fineness was 89.8 dtex, the hot water shrinkage was 5.3%, and the yarn length difference was 2.2%. The resulting composite false-twisted blended yarn had a 100% crimp structure and contained false-twist crimps overall.

The resulting composite false-twist blended yarn was used at a blending ratio of 100% to produce a plain knit circular knit fabric using a 28G circular knitting machine with 48 wales/2.54 cm and 75 courses/2.54 cm. The fabric was processed under the same conditions as in Example 2 and the heathered feel was evaluated using the same method as in Example 1. The resulting knitted yarn was entangled entirely using a Taslan nozzle, forming fine loops, making it impossible to measure the number of entanglements, number of open portions, and entanglement spacing. The resulting circular knit fabric had a marbled heathered feel and a surface texture with a weak gradation effect, failing to achieve the desired heathered feel.

[Comparative Example 4]
A 90 decitex, 36 filament, cationic dyeable, highly oriented, undrawn polyester multifilament yarn (birefringence index Δn: 0.018) (made of cationic dyeable polyethylene terephthalate copolymer) (raw yarn A) produced at a spinning speed of 2100 m/min and a 90 decitex, 48 filament, highly oriented, undrawn polyester multifilament yarn (birefringence index Δn: 0.036) (made of cationic non-dyeable polyethylene terephthalate) (raw yarn B) produced at a spinning speed of 2500 m/min were false-twisted according to the manufacturing process shown in Figure 1 under the conditions shown in Table 1, and each yarn (the yarn derived from yarn A is referred to as yarn A, and the yarn derived from yarn B is referred to as yarn B) was subjected to an entanglement/mixing process using a special interlace nozzle (KF-JET manufactured by Heberlein) to obtain an SZ composite false-twisted mixed yarn.

The number of entanglements under a load of 0.1 g/dtex for the obtained composite false twist blended yarn was 53/m, and the number of entanglements under a load of 0.5 g/dtex was 35/m. Of the 30 spread portions, 21 had an entanglement spacing of 1 mm or more but less than 25 mm, 9 had an entanglement spacing of 25 mm or more but less than 50 mm, and 0 had an entanglement spacing of 50 mm or more. The tensile strength was 2.15 cN/dtex, the elongation was 23.3%, the total fineness was 112.0 dtex, the hot water shrinkage rate was 5.5%, and the yarn length difference was 2.6%. The crimp structure of the obtained composite false twist blended yarn was 100%, and the yarn had false twist crimps overall.

A plain woven fabric was produced using the obtained composite false twist blended yarn as the warp and weft yarns, with a warp density of 82 threads/2.54 cm and a weft density of 72 threads/2.54 cm. The fabric was processed under the same conditions as in Example 1 and evaluated for its heathered feel using the same method as in Example 1. The number of entanglements in the resolved yarns of the obtained fabric was 42/m, and of 30 spread portions, 21 had an entanglement spacing of 1 mm or more but less than 25 mm, 9 had an entanglement spacing of 25 mm or more but less than 50 mm, and 0 had an entanglement spacing of 50 mm or more. The obtained plain woven fabric had a marbled heathered feel and a surface texture with a weak gradation effect, and the desired heathered feel was not achieved.

1: Cationic dyeable polyester multifilament highly oriented undrawn yarn 2: Guide 3: First feed roller 4: First heater 5: First false twisting device 6: Third feed roller 7: Entangling nozzle 8: Fourth feed roller 9: Composite false twist blended yarn 10: Take-up roller 11: Polyester multifilament highly oriented undrawn yarn 12: Guide 13: Second feed roller 101: First heating pin 102: Third feed roller 103: Fifth feed roller 104: Sixth feed roller 105: Second heating pin 106: Fourth feed roller 201: Third feed roller 202: Fifth feed roller 203: Second heater 204: Second false twisting device 205: Fourth feed roller

Claims (8)

A composite false twist blended yarn composed of at least two types of thermoplastic multifilament yarn, which has a false twist crimp overall, and of 30 spread portions, there are 1 to 15 spread portions with an entanglement interval of 1 mm or more but less than 25 mm, 1 to 15 spread portions with an entanglement interval of 25 mm or more but less than 50 mm, and 1 to 10 spread portions with an entanglement interval of 50 mm or more. The composite false twist blended yarn according to claim 1, wherein the thermoplastic multifilament yarn comprises cationic dyeable polyester multifilament yarn A and cationic non-dyeable multifilament yarn B, and the cationic dyeable polyester multifilament yarn A accounts for 20% by mass or more and 80% by mass or less. A composite false twist blended yarn according to claim 1 or 2, wherein at least one of the thermoplastic multifilament yarns is a thermoplastic multifilament yarn having latent crimping properties. A composite false twist blended yarn according to any one of claims 1 to 3, wherein the at least two types of thermoplastic multifilament yarns each have thickness variations in the fiber axis direction, the thick portions of the yarns are out of phase with each other, the yarn structure has a partially reversible yarn length difference, and the actual yarn length difference between the yarns is 3% or less. A composite false twist blended yarn according to any one of claims 1 to 4, in which the number of entanglements under a load of 0.1 g/dtex is 2 or more and 45 or less/m, and the number of entanglements under a load of 0.5 g/dtex is 0 or more and 30 or less/m. A woven or knitted fabric, at least in part, made using the composite false twist blended yarn described in any one of claims 1 to 5. A woven or knitted fabric comprising, at least in part, a composite false twist blended yarn composed of at least two types of thermoplastic multifilament yarn, which has a false twist crimp overall, and in which, among 30 spread portions, there are 1 to 15 spread portions with an entanglement interval of 1 mm or more but less than 25 mm, 1 to 15 spread portions with an entanglement interval of 25 mm or more but less than 50 mm, and 1 to 10 spread portions with an entanglement interval of 50 mm or more. The woven or knitted fabric according to claim 6 or 7, wherein the number of entanglements in the composite false twist blended yarn is 1 or more/m and 35 or less/m.