JPH0512446B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention is manufactured using a single processing weight, using a variable cross-section shrinkage mixed fiber yarn in which each single filament has a mushroom-shaped cross section with a trunk protruding from the umbrella portion. However, different filaments are mixed in the wide width of the crimped shape, there is no difference in the actual filament length, and the processed yarn is stable against external forces and has a special texture. Concerning the manufacturing method. <Conventional technology> Conventionally, by changing the cross-sectional shape of synthetic resin from a circular shape to, for example, a triangular or C-shape, it is possible to remove the metallic luster and slimy feel characteristic of synthetic fibers and to create a structure similar to that of silk fiber fabrics. Various attempts have been made to impart luster and texture to synthetic resin fabrics. On the other hand, when a thermoplastic synthetic fiber yarn whose single filament thickness, cross-sectional shape, heat shrinkage characteristics, etc. are uniform in the longitudinal direction and cross-sectional direction of the yarn is subjected to normal false twisting and crimping processing, the processed yarn becomes The crimped shapes of the constituent single filaments are similar and the appearance of the fabric is monotonous. A method for producing special false-twisted yarn that is twisted and crimped has been proposed. However, when the cross-sectional shape of a single filament is triangular or star-shaped, the cross-section has convex portions and concave portions of approximately the same shape alternately in the circumferential direction, so that it is difficult to twist during false twisting. When the fibers are subjected to a heating action, etc., the protrusions of other fibers enter the recesses of the fibers, causing a so-called filling phenomenon in which the fibers stick together. Therefore, when the fibers in the yarn or fabric are restrained, ,
It has the disadvantage of lacking a sense of fullness, and in addition, different shrinkage mixed fiber yarns with single filament cross-sections that are triangular or star-shaped can be simply subjected to relaxation heat treatment and then false-twisted to cause crimping due to differential shrinkage. If you are trying to obtain a textured yarn with a mixture of differences, in this case it is necessary to perform false twisting to maintain the yarn length difference that occurred during the relaxation heat treatment. High-shrinkage filaments, which have a relatively short yarn length, must be false-twisted without being overstretched compared to low-shrinkage filaments. Therefore, the resulting processed yarn has a high residual elongation and is stable against external forces. It has a disadvantage that it is easily shifted due to "iron" in the weaving and weaving process because of the low yarn length difference and the yarn length difference. <Problems to be Solved by the Invention> As a result of various studies to solve the above-mentioned drawbacks of the prior art, the present invention has been made based on the results that the cross-sectional shape of the single filament is within the cross-section of the yarn in the longitudinal direction of the yarn. The texture and gloss are improved by having a cross section that is geometrically difficult to close-packed, having a flat reflective surface and a ridge, and a differential shrinkage mixed fiber yarn having such a cross section. The present invention was achieved based on the discovery that by applying more crimps to the low-shrinkage yarn side, a processed yarn that has the above-mentioned texture and luster and is stable against external forces can be obtained. Therefore, in the present invention, the resulting fabric has a luster similar to that of silk fibers, has a rich feeling of fullness, and is also rich in a silky feel, and in spite of the fact that filaments with widely different crimped shapes are mixed. The technical objective is to obtain a false twisted yarn that has no difference in actual filament length and is stable against external forces. <Means for Solving the Problems> That is, the present invention provides a thermoplastic synthetic fiber multifilament yarn containing a mixture of filaments whose thermal stress is reversed under a high relaxation rate and a low relaxation rate or under a stretched state. The cross section of the single filament is mushroom-shaped, consisting of a triangular umbrella part and a trunk, and the thermal stress of the low shrinkage filament is high in the irregular cross-section different shrinkage mixed fiber yarn that satisfies the following formulas () and (). After a relaxation heat treatment is performed in advance under a relaxation rate lower than the thermal stress of the shrink filament, false twisting is performed under a relaxation rate or under a stretching state in which the thermal stress of the two is reversed, and the crimp rate of the high shrinkage filament is further increased. This is a method for producing a special false twisted yarn, which is characterized by stretching to a crimp ratio lower than that of a low shrinkage filament. 0.6H ₁ ≦H ₂ ... () K ₁ ≧2K ₂ ... () However, H ₁ : Distance from the tip of the umbrella to the bottom, H ₂ : Distance from the bottom of the cap to the end of the trunk, K ₁ ; Maximum width of the cap; K ₂ : Maximum width of the cap between the center of the bottom of the cap and the end of the cap, and the end of the cap. The present invention will be explained in more detail below. First, the supplied yarn used in the present invention is a thermoplastic synthetic fiber multifilament yarn in which a plurality of high-shrinkage filaments and low-shrinkage filaments are mixed, and its thermal shrinkage stress is in a high relaxation rate, a low relaxation rate, or in a stretched state. It is made of a mixed yarn with different shrinkage that is reversed at the bottom, and the single filament has a mushroom-shaped cross section consisting of a triangular umbrella part and a trunk, and the yarn has an irregular cross section that satisfies the following formulas () and (). It is. Here, a mixed shrinkage yarn containing filaments whose thermal stress is reversed under a high relaxation rate and a low relaxation rate or under a drawing state is a mixed fiber yarn with different shrinkage, which is characterized by the heat stress of the high shrinkage filaments under a high relaxation rate as shown in Figure 2. It refers to a mixed fiber yarn in which two or more types of filament groups coexist, with high shrinkage stress and low shrinkage filaments having high heat shrinkage stress under low relaxation rate or stretching conditions. In order to obtain such a differentially shrinkable mixed fiber yarn, the properties of the polymer, the spinning temperature,
It can be obtained by appropriately selecting cooling conditions during spinning or heat treatment during stretching. For example, it can be obtained by spinning the same polymer, dividing it into two parts, stretching it under different heat treatment conditions, and then doubling it. The cross-section of the single filament of the above-mentioned differentially shrinkable mixed fiber yarn is a triangular umbrella portion 11 as shown in FIG.
and a substantially rectangular trunk 12 protruding from substantially the center of the base. Therefore, although the processed yarn obtained by the method of the present invention is slightly deformed, it maintains approximately the cross-sectional shape of the supplied yarn, and the triangular umbrella portion 11 and trunk portion 12 are asymmetrical and have different shapes, so that As with threads with different cross-sections such as triangular or star-shaped cross-sections, the convex part of another filament enters the concave part of the filament and the so-called filling phenomenon in which the filaments come into close contact with each other is less likely to occur. Many voids are formed in the fabric, giving the fabric a full and warm feel. In addition, the cross-sectional shape of the filament of the differentially shrinkable mixed yarn is determined by H ₁ being the distance from the tip of the umbrella portion 11 to the bottom, H 2 being the distance from the bottom of the umbrella portion 11 to the end of the trunk 12 , and H ₂ being the distance from the bottom of the umbrella portion 11 to the end of the trunk 12 . When the maximum width of the trunk 12 from the center to the end of the trunk 12 to the end of the trunk 12 is _K2 , these satisfy the following formulas () and (). 0.6H ₁ ≦H ₂ ... () K ₁ ≧2K ₂ ... () In other words, since the cross-sectional shape of the filament is such that the length of the trunk 12 is 0.6 times or more the length of the umbrella portion 11, the protrusion of the trunk 12 is This further promotes the effect of preventing the above-mentioned filling phenomenon. Furthermore, since the maximum width K ₁ of the umbrella portion 11 is more than twice the maximum width K ₂ of the trunk 12, each vertex of the umbrella portion 11 and the trunk 12 protrude outward from the yarn surface, and thus the obtained There are irregularities on the surface of the fabric, and when you touch it, your fingertips are pleasantly stimulated by the protruding part of the filament, and the contact area transmitted to your fingertips is also reduced, so it has a silky smooth feel and a rich dry and smooth feeling. It has a silk-like texture. In this case, the length H2 of the trunk 12 is the length _H2 of the umbrella part 11.
If the length H _is less than 0.6 times, it is preferable because when the yarns are bundled, the convex portions of the filaments will enter the concave portions of other filaments, reducing the voids between the filaments, resulting in poor fluffiness when made into a fabric. do not have. Furthermore, the maximum width K ₁ of the umbrella part 11 is determined by the executive 12.
By making the maximum width _K2 more than twice the umbrella part 1
The light rays reflected at 1 and the light rays reflected at the trunk 12 partially cancel each other out, giving a silk-like soft luster, and also increasing the voids between the filaments to improve the sense of fullness. be able to. In this case, the maximum width _K1 of the umbrella part 11 is
If it is less than twice the maximum width K ₂ , the cross-sectional shape of the filament becomes flat, and the surface of the resulting fabric becomes less uneven and feels slimier, and the angles of light reflection by the umbrella portion 11 and the trunk portion 12 become closer. , which is not preferable because it becomes shiny and metallic-like. Next, the above-mentioned differential shrinkage mixed fiber yarn with a mushroom-shaped cross-sectional shape is
This is subjected to a relaxation heat treatment in advance at a relaxation rate in which the thermal stress of the low-shrinkage filament is lower than that of the high-shrinkage filament, and then false-twisting is performed under a stretching state at a relaxation rate in which the thermal stresses of the two are reversed. That is, when the differential shrinkage mixed fiber yarn is heat-treated under high shrinkage, that is, high relaxation rate (region A in Figure 2), the tension of the low shrinkage filament (L yarn) is higher than the tension of the high shrinkage filament (H yarn). The low-shrinkage filaments (L-yarns) are slackened and substantially longer than the high-shrinkage filaments (H-yarns), and the low-shrinkage filaments (L-yarns) are located in the outer layer of the blended yarn. If the low shrinkage filaments (L yarns) are twisted in that state by false twisting, the low shrinkage filaments (L yarns) will be twisted while forming loops due to slack, but in the case of the present invention, the thermal stress of the low shrinkage filaments (L yarns) Since the fibers are false-twisted at a higher relaxation rate or drawn state (region B in Figure 2) than the high shrinkage filaments (H yarns), the low shrinkage filaments (L yarns), which had low shrinkage during the relaxation heat treatment, are subjected to sufficient stress. Crimp is added. On the other hand, high shrinkage filaments (H yarns) may appear to have higher shrinkage than low shrinkage filaments, but their robustness against external forces is relatively low. In addition, in order to perform the false twisting process as described above, even after the relaxation heat treatment, the thermal properties of the yarn used in the present invention, i.e., the thermal shrinkage stress of the low shrinkage filament is higher than that of the high shrinkage filament under a low relaxation rate or under a drawing state. It is necessary to perform a relaxation heat treatment that maintains the characteristic of increasing the temperature, but for this purpose, it is desirable to set temperature conditions that do not significantly promote crystallization of the high-shrinkage filament, which becomes highly stressed during the relaxation heat treatment. Thermal stress or heat shrinkage stress referred to here refers to the tension of the yarn obtained as the sum of the stresses exhibited by each single filament that makes up the yarn. This refers to the tension of the yarn measured in a hot atmosphere after separating it into a group of low-shrinkage filaments and a group of low-shrinkage filaments. Next, in the present invention, the false twisted processed yarn is further stretched so that the crimp ratio of the high shrinkage filaments is lower than the crimp ratio of the low shrinkage filaments. Here, the difference in crimp rate means 0.1g of yarn/
It is sufficient if there is a difference in appearance under the tension of d, but quantitatively, it is important to note that there is a difference in the appearance under the tension of
The difference in expansion/contraction rate measured according to JISL1090 is 15
% or more. By drawing in this way, crimps that are stable against external forces remain as highly crimped yarns, while crimps that are unstable against external forces are reduced. The result is a false-twisted yarn in which filaments of different widths coexist, and since both high-shrinkage filaments and low-shrinkage filaments are drawn during the drawing process, there is no substantial difference in yarn length between the two filaments. There is no problem of shearing even when ironed during the knitting and weaving process. Due to the synergistic effect of the special cross-sectional shape of the single filament and the special crimping process, the processed yarn thus obtained has unprecedented characteristics such as silk-like luster and texture as well as a sense of volume. You can get fabric. In addition, by using a mixed fiber yarn in which the thermal shrinkage stress ratio during relaxation heat treatment and the thermal stress ratio during false twisting are largely reversed, the number of false twists during false twisting is low, and the stretching tension during stretching is reduced. By setting the draw ratio to be sufficiently higher than the untwisting tension during false twisting, low crimp filament,
In other words, it is possible to make the high shrinkage filament substantially filament-like, and in this case, the appearance of the fabric,
A texture that combines the characteristics of supplied yarn and processed yarn can be obtained. FIG. 4 is a process schematic diagram showing one example of the manufacturing process of the method of the present invention. After that, the filament is subjected to a relaxing heat treatment by the first heater 2 at a high shrinkage rate between the feed roller 1 and the first delivery roller 3, and after passing through the first delivery roller 3, the filament is highly shrinkable between the first delivery roller 3 and the second delivery roller 6. The filament is twisted by the false twisting spindle 5 under a relaxation rate or stretching ratio in which the thermal stress between the filament and the low shrinkage filament is reversed, and is heat-set by the second heater 4, and then passed through the second delivery roller 6 and the second delivery roller 6. The high-shrinkage filament is stretched between the third delivery roller 7 so that the crimp ratio is lower than the crimp ratio of the low-shrinkage filament, and is then wound up into a package 9 by a wind-up roller 8 via the third delivery roller 7. Thermoplastic synthetic fibers that can be used in the irregular cross-section, different shrinkage mixed yarn of the present invention include synthetic fibers obtained from polymers such as polyester, polyamide, and polyacrylonitrile, and copolymers and blend polymers thereof. In order to obtain the desired silk-like luster and texture, polyester fibers with excellent physical properties are preferred. <Examples> The present invention will be specifically described below based on Examples. Example The filament has the same denier and the cross-sectional shape of the filament is mushroom-shaped as shown in Fig. 1, H ₂ /H ₁ = 0.7, K ₁ /K ₂ =
2.2, and each half of the constituent filaments exhibits the thermal stress characteristics as shown in Figure 2 through heat treatment during stretching. Polyethylene terephthalate irregular cross-section irregular shrinkage mixed fiber yarn (bright yarn) 75d/48f is shown in Figure 4. According to the process, relaxation heat treatment, false twisting, and stretching were performed under the conditions shown in Table 1 to produce a special false twisted yarn according to the method of the present invention. After the relaxation heat treatment, the thermal stress of the low shrinkage filament measured under the draw ratio (1.05) during false twisting was greater than that of the high shrinkage filament.

[Table] The special false-twisted yarns obtained had a distinct difference in crimpability, as if the two yarns had been separately false-twisted and crimped. Further, even when this processed yarn was squeezed and squeezed to a tension of 30 g, no shearing phenomenon was observed at all.
In addition, this processed yarn is used for the warp and weft to increase the warp density.
The fabric was woven into a plain weave with a weft density of 85 threads/inch and a weft density of 84 threads/inch, and then this gray fabric was subjected to relaxation scouring, presetting, and dyeing final setting.The fabric had a mellower luster than the comparative sample described later, and was dry. The product was rich in texture and silkiness, and also had a voluminous feel unique to processed yarns, which cannot be obtained by using raw yarns. Comparative example Polyethylene terephthalate 37.5d/37.5d/2.5 mol% isophthalic acid copolymerized with equal filament denier and circular filament cross-section
24f and polyethylene terephthalate 37.5d/24f are spun and blended to make a different shrinkage blend yarn (bright yarn) 75d/48f, which is the same brand as in the example and whose heat shrinkage stress does not reverse as shown in Figure 3. Comparative textured yarns were made by subjecting them to relaxation heat treatment and then false twisting under the conditions shown in the table.

[Table] This processed yarn had a bulging appearance with many fine loops, but the crimp form was not clearly two-layered, and it was resistant to ironing under 30g of tension. A significant deviation occurred. When this processed yarn was made into a fabric in the same manner as in the examples, it lacked luster, dryness, and crispness. On the other hand, the volume feeling was similar to that of the examples, with a thick feeling peculiar to the use of processed yarn, but the appearance lacked elegance compared to the examples. <Effects of the Invention> As described above, since the method of the present invention has the above-mentioned configuration, it is possible to use a differentially shrinkable mixed fiber yarn with a specific cross-sectional shape as the supplied yarn and to crimp it under specific conditions. Due to the synergistic effect with the method of the present invention, the fabric obtained by the method of the present invention can be given a silk-like luster, a feeling of fullness, and a feeling of crispness, and even when filaments with widely different crimp shapes are mixed. Regardless, it is possible to obtain a processed yarn that has no substantial difference in filament length and is stable against external forces. Further, the method of the present invention has the advantage that it can be manufactured using a single processing weight and does not require complicated processing equipment.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an example of a filament of the irregular cross-section, different shrinkage mixed yarn according to the present invention, and FIG. 2 is a cross-sectional view of a high-shrinkage filament and a low-shrinkage filament of the irregular cross-section different shrinkage mixed yarn according to the present invention at 200°C. Graph showing the relationship between relaxation rate and thermal stress, 3rd
The figure is a graph corresponding to FIG. 2 of the conventional differential shrinkage mixed fiber yarn, and FIG. 4 is a process schematic diagram showing an example of the manufacturing process of the method of the present invention. 1... Feed roller, 2... First heater, 3
...First delivery roller, 4...Second heater, 5
. . . False twist spindle, 6 .

Claims (1)

[Scope of Claims] 1. A thermoplastic synthetic fiber multifilament yarn containing a mixture of filaments whose thermal stress is reversed under a high relaxation rate and a low relaxation rate or under a drawing state, wherein the cross section of the single filament is The thermal stress of the low-shrinkage filament is higher than that of the high-shrinkage filament in a mushroom-shaped yarn consisting of a triangular umbrella and a trunk, and that satisfies the following formulas () and (). After pre-relaxation heat treatment under a low relaxation rate, false twisting is performed under a relaxation rate or under a stretching state where the thermal stress of both is reversed.
A method for producing a special false-twisted yarn, which further comprises drawing the high-shrinkage filament so that the crimp ratio is lower than the crimp ratio of the low-shrinkage filament. 0.6H ₁ ≦H ₂ ... () K ₁ ≧2K ₂ ... () However, H ₁ : Distance from the tip of the umbrella to the bottom, H ₂ : Distance from the bottom of the cap to the end of the trunk, K ₁ ; Maximum width of the cap; K ₂ : Maximum width of the cap between the center of the bottom of the cap and the end of the cap, and the end of the cap.