JP2001003234A - Blended yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a blended yarn which is useful for woven fabrics, knitted fabrics, or so on, having excellent swollen, soft and repulsive touches in extremely simple processes, by blending low elongation fibers comprising a polyester with high elongation fibers comprising specific sheath-core conjugate fibers. SOLUTION: This blended yarn comprises low elongation fibers and high elongation fibers. The low elongation fibers comprise a polyester such as a highly shrinking polyester, and the high elongation fibers comprise sheath-core conjugate fibers which comprise a polyester in the sheath portions and a polymer having higher elongation viscosity temperature dependency than that of the sheath polyester in the core portion. The difference between the elongation of the low elongation fibers and the elongation of the high elongation fibers is preferably >=80%. The polymer arranged in the core portions of the high elongation fibers is preferably used in an amount of 2 to 5 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a swelling, soft,
The present invention relates to a mixed fiber yarn which is a raw material for producing a different shrinkage mixed fiber yarn or a false twisted yarn excellent in resilience in an extremely simple process.

[0002]

2. Description of the Related Art Polyester has various excellent properties including mechanical properties, and is therefore used in various fields including clothing. In clothing applications, quality has been improved targeting natural fibers, but especially as a means to realize a swelling and soft texture.
A so-called shrinkage-differential mixed yarn, in which yarns having different shrinkage characteristics due to heat are mixed, is widely used.

[0003] As a low-cost production method of shrinkage difference mixed fiber yarn,
In the spinning / winding step, a spinning fiber blending method in which a low shrinkage yarn and a high shrinkage yarn are blended has been employed. For example, Japanese Patent Application Laid-Open No. 2-195
No. 28 discloses homopolyethylene terephthalate as a low shrinkage component and isophthalic acid (hereinafter IP) as a high shrinkage component.
A) and polyester obtained by copolymerizing 2.2 bis {4- (2-hydroxyethoxy) phenyl} propane (hereinafter abbreviated as BHPP) were used to perform mixed fiber spinning, and the undrawn yarn was once wound up. A very simple method for producing a differential shrinkage mixed fiber yarn, which is post-drawn, is disclosed.

On the other hand, recently, a shrinkage-differential mixed yarn using so-called spontaneously elongated yarn, which exhibits extensibility by heat, has attracted attention. If this type of shrinkage differential mixed yarn is used, a sufficient yarn length difference can be obtained after dyeing even if the density of the woven fabric increases, and the shrinkage differential mixed yarn described in JP-A-2-19528 was used. As compared with the case, a cloth excellent in swelling and softness can be obtained.

A method for producing a spontaneously elongated yarn is disclosed in, for example,
No. 3,352,836, a method in which a polyester partially oriented yarn (hereinafter abbreviated as POY) is stretched and then subjected to a relaxation heat treatment,
Japanese Unexamined Patent Publication (Kokai) No. 2-293410 discloses a method in which POY is subjected to a relaxation heat treatment as it is. Then, the spontaneously elongated yarn is blended later with a separately produced shrinkable yarn (hereinafter, abbreviated as a post-blending method) to obtain a shrinkage-differentiated mixed yarn.

[0006] As described above, since the relaxation heat treatment is essential for the production of spontaneously elongated yarn, it has been common to separately produce the spontaneously elongated yarn and the shrinkable yarn and then to carry out post-fiber mixing. For this reason, spontaneously elongated yarns and shrinkage yarns, that is, at least two types of yarns are manufactured in separate steps, which alone increases the cost. Furthermore, since the cost for post-fiber mixing is increased, the cost is much lower than that of the spin-fiber mixing method.

[0007]

SUMMARY OF THE INVENTION The present invention provides a mixed fiber which is a raw material for enabling production of a differential shrinkage mixed fiber using spontaneously elongated yarn by a simple process.

[0008]

An object of the present invention is to provide a mixed yarn comprising a low elongation yarn and a high elongation yarn, wherein the low elongation yarn is made of polyester and the high elongation yarn is made of polyester. And a core-sheath composite yarn in which a polymer having a higher temperature dependence of elongational viscosity than the sheath polyester is disposed in the core portion.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester referred to in the present invention includes polyethylene terephthalate (hereinafter abbreviated as PET), polypropylene terephthalate, polybutylene terephthalate and the like. PET is the most general and preferred. Further, a part of the diol component and a part of the acid component are each 15
It may be substituted with another copolymerizable component within the range of mol% or less. They may also contain additives such as other polymers, matting agents, flame retardants, antistatic agents, pigments and the like.

Hereinafter, a description will be given of PET as an example.

The present invention relates to a mixed fiber used as a raw material for obtaining a shrinkage-differentiated mixed yarn containing spontaneously elongated yarn by a simple process. With a simple process, a shrinkage difference mixed yarn including spontaneously elongated yarn can be obtained. And it is particularly important that the material mixed fiber is a mixed fiber consisting of a low elongation yarn and a high elongation yarn. When such mixed yarns with different elongations are used, low draw ratio is applied to high elongation yarns, and high draw ratio is applied to low elongation yarns, and mixed draw yarns having different effective draw ratios can be obtained. You can.
Then, the high elongation yarn on the low-magnification drawing side can be a spontaneous elongation yarn, and the low-elongation yarn on the high-magnification drawing side can be a contraction yarn. For this purpose, the difference in elongation between the high elongation yarn and the low elongation yarn is preferably 80% or more. 80% elongation difference
Above is preferable because the difference in shrinkage between the spontaneously elongated yarn and the shrinkable yarn becomes large, and the feeling of swelling, softness and resilience when made into a fabric is improved. The elongation difference is preferably 100% or more.

Further, the high elongation yarn has a polyester in the sheath (sheath polyester) and a polymer in the core having a higher temperature dependency of elongational viscosity than the sheath polyester (core polymer).
It is important that the core-sheath composite yarn is provided with Here, the core polymer has a function of suppressing the orientation of the yarn and increasing the elongation.
No. 920. Specific examples of the core polymer include a polystyrene-based polymer, a polymethacrylate-based polymer, a polymethylpentene-based polymer, and the like, and a polystyrene-based polymer is most preferable in terms of cost and spinnability. When the composite ratio is 2 to 5% by weight, a sufficient elongation effect can be obtained, and the yarn can be stably spun without thread breakage. Then, by encapsulating the core polymer in the core of the yarn and making the yarn surface PET,
Heat resistance can be ensured, and the process stability during stretching and false twisting can be improved. Also, when dyeing a fabric, beautiful dyeing can be achieved without causing dullness or spots.

[0013] It is important that the low elongation yarn is formed of polyester, whereby the mechanical strength of the mixed yarn can be ensured. In addition, if the polymer constituting the low elongation yarn is a polymer having a higher shrinkage than the sheath polyester forming the sheath portion of the high elongation yarn, the difference in shrinkage ratio when the yarn is made into a mixed yarn having a different shrinkage is increased, and the swelling of the fabric is increased. This is preferable because the feeling can be improved. As the high shrinkage polyester, it is preferable to employ a polyester obtained by copolymerizing IPA. IPA copolymerization rate is 3-12mo
If it is 1%, a fiber having a sufficiently high shrinkage can be obtained.
In addition, BHPP or the like may be copolymerized in addition to IPA to further increase the shrinkage.

When the mixed fiber of the present invention is used, compared with the conventional relaxation heat treatment and post-fiber mixing, the shrinkage difference mixed yarn using the low elongation yarn as the spontaneously elongated yarn only in a simplified process of drawing and heat treatment. There is a great advantage that it can be obtained. As a result, the cost can be significantly reduced.

Although it is not clear why the low elongation yarn can be made into a spontaneously elongated yarn only by stretching and heat treating the mixed fiber of the present invention, a special fiber structure suitable for spontaneous elongation is obtained by the action of a special core polymer. It is thought that it is to form. For example, it is possible that ultrafine crystal nuclei are generated in the sheath polyester due to the difference in the viscosity behavior between the core polymer and the sheath polyester during the spinning process, and this may be a precursor of a fiber structure advantageous for spontaneous elongation.

The method for producing the mixed fiber of the present invention is not limited at all, and examples thereof include the following method.
That is, the high elongation yarn is a core-sheath composite yarn in which the polyester is disposed in the sheath portion, and a polymer having a higher temperature dependency of elongation viscosity than the polyester is disposed in the core portion, and the low elongation yarn is a polyester single yarn. It can be obtained by discharging two or more kinds of yarns from the same spinneret, cooling and solidifying the yarns, applying an oil agent for fibers and entanglement, and drawing the yarns at a spinning speed of 2500 m / min or more.

In the present invention, the yarn cross-sectional shape is not particularly limited, but a dry touch can be obtained if the yarn has a modified cross-sectional shape such as a trilobal cross-section, a square cross-section, or a multi-lobal cross-sectional shape. The range of the single-filament fineness is not particularly limited, but is preferably determined so that the high elongation yarn becomes 0.5 to 6.0 dtex and the low elongation yarn becomes 2.0 to 6.0 dtex after stretching and heat treatment. When used for thin garments such as blouses, the total fineness of the mixed yarn is 3% after stretching and heat treatment.
It is preferable to set it so as to be 0 to 110 dtex. Further, the mixed ratio of the high elongation yarn and the low elongation yarn is preferably 10/90 to 90/10 in terms of the fineness ratio.

The mixed fiber of the present invention may be drawn and heat-treated to give a shrinkage-differentiated mixed fiber, or may be subjected to draw false twisting to be used as a false twisted yarn having an excellent swelling feeling due to a difference in yarn length. . Usually, such false elongation difference twisted yarn is prepared by separately preparing a high elongation yarn and a low elongation yarn, and then performing a false twisting process after blending. Since the yarn and the low elongation yarn are separately produced, and then false twisted after blending, the process becomes complicated. In addition, this requires a double creel false twisting machine in which two creels are prepared for a single-weight false twisting machine, and there are restrictions on the apparatus. However, when the mixed fiber of the present invention is used, it is possible to obtain a yarn having excellent swelling feeling, such as a composite false twisted yarn, by simply performing normal draw false twisting with a normal single creel false twisting machine. There is also.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to embodiments. In addition, the measuring method in the Example used the following method.

A. Intrinsic viscosity [η] Measured at 25 ° C. in orthochlorophenol.

B. Dry heat shrinkage and boiling water shrinkage Dry heat shrinkage (%) = [(L0−L2) / L0)] × 10
0 Shrinkage ratio of boiling water (%) = [(L0−L1) / L0)] × 1
00 L0: Skew the drawn yarn, and the initial load is 0.09 cN / dte
The original length of the skein measured under x L1: The skein measured L0 is treated in boiling water for 15 minutes in a substantially load-free state, and the initial load after air drying is 0.09c.
Skew length under N / dtex L2: The skein whose L1 was measured was further subjected to 15 treatments at 160 ° C. in dry heat and in a load-free state, and an initial load of 0.09 cN after air drying.
Skew length under / dtex Strength and elongation The initial sample length was set to 50 mm and the tensile speed was set to 50 mm / min, and a load-elongation curve was obtained under the conditions shown in JIS L1013. Next, the load value was divided by the initial fineness, which was taken as the strength, and the elongation was divided by the initial sample length to obtain the elongation.

D Birefringence The retardation and optical path length of a single yarn were measured with an OLIMPUS BH-2 polarizing microscope, and Δn was determined. Δn of the sheath PET portion of the core-sheath composite yarn was measured by the method described in JP-A-9-176920.

Example 1 As a low elongation yarn, a homo PET having an intrinsic viscosity of 0.63 (does not contain titanium oxide), and as a high elongation yarn, the homo PET and polystyrene ("Stylon" 685 manufactured by Asahi Kasei Corporation) were separately used. Homo PET is melted at 285 ° C., and the polystyrene is melted at 210 ° C., and filtered separately using a stainless steel non-woven fabric filter having an absolute filtration diameter of 15 μm.
The liquid was discharged from a die having a hole length of 0.4 mm and 36 holes. At this time, the core / sheath = polystyrene (5.0% by weight)
/ PET (95 wt%) core-sheath composite yarn (hereinafter referred to as PS
/ PET composite yarn). And the spinning temperature 288 ° C,
At a spinning speed of 5000 m / min, a 72 dtex, 36-filament undrawn mixed yarn was wound up. At this time, low elongation yarn,
The same fineness and the same number of filaments (36 dt)
ex-18 filaments). The low elongation yarn had a birefringence of 0.085 and an elongation of 70%, and the low orientation side had a birefringence of 0.033 and an elongation of 180% (Table 1).

Using a drawing machine having a pair of hot rollers as shown in FIG. 1, a temperature of the first hot roller 3 is 90 ° C., and a drawing speed (peripheral speed of the second hot roller 4) is applied to the mixed yarn.
Stretching was performed at 800 / m and a draw ratio of 1.10 while changing the temperature of the second hot roller 4 as shown in Table 2 (Experiments Nos. 1 to 3). The contact time between the second hot roller 4 and the yarn was 0.15 seconds.

When the temperature of the second hot roller is 110 ° C. or higher, the high elongation yarn exhibits spontaneous elongation, and the low elongation yarn has good shrinkage stress and high elongation characteristics (Table 2). .
In addition, there was no yarn sway or yarn breakage during stretching, and the yarn could be produced without any problem. The success rate of restart after Doff was also good. In addition, it was of high quality with almost no staining spots.

The single undrawn yarn of each component was obtained by suction-separating the other yarn with an aspirator.
Then, by drawing them separately, single drawn yarns of each component could be obtained. By subjecting them to various measurements, the physical properties of each component alone could be determined. In the following examples, the physical properties of each component alone were similarly obtained.

[0027]

[Table 1]

[0028]

[Table 2] Example 2 The temperature of the second hot roller 4 was 120 ° C., and the stretching ratio was 1.
Stretching was performed under the same conditions as in Example 1 except that the temperature of the first hot roller 3 was changed as shown in Table 3 by a factor of 10 (Experiment Nos. 4 to 8). Table 3 shows the physical property values. When the temperature of the first hot roller 3 is 110 ° C. or less, it is understood that the low-oriented yarn has spontaneous elongation. Also, yarn swaying during stretching,
Yarn could be produced without any problems such as thread breakage. The success rate of restart after Doff was also good. In addition, it was of high quality with almost no staining spots.

However, if the temperature of the first hot roller 3 is 3
In the case of 0 ° C., although not so much as to cause a problem, some staining spots occurred. The temperature of the first hot roller 3 is 100 ° C.
Above this, the yarn swayed slightly, and the spontaneous elongation rate was also low.

[0030]

[Table 3] Example 3 The core polymer of the yarn with a high elongation at a spinning speed of 4000 m / min was converted from polystyrene to polymethylpentene (“TP” manufactured by Mitsui Ishika Co., Ltd.).
X "RT-18), the composite ratio was 2% by weight, and the discharge rate was further changed. The mixed fiber was wound under the same conditions as in Example 1 except that the mixed fiber was changed to 92 dtex-36 filament. At this time, the low elongation yarn has a birefringence of 0.066 and an elongation of 95%, and the high elongation yarn has a birefringence of 0.020 and an elongation of 21.
5% (Table 1).

This mixed fiber was drawn under the same conditions as in Example 1 except that the temperature of the second hot roller 4 was changed to 120 ° C. and the draw ratio was changed as shown in Table 4 (Experiment Nos. 9 and 1).
0). Table 5 shows the physical property values. When the draw ratio is 1.35 or less, it is understood that the high elongation yarn exhibits spontaneous elongation, and the low elongation yarn also has good shrinkage stress and high elongation characteristics. Also,
Yarn could be produced without any problems without yarn shaking or yarn breakage during stretching.
The success rate of restart after Doff was also good. In addition, it was of high quality with almost no staining spots.

[0032]

[Table 4] Example 4 The spinning speed was 3500 m / min, the discharge amount was changed, and the mixed fiber was used.
Example 1 except that 99dtex-36 filament was used.
The undrawn mixed fiber was wound under the same conditions as described above. At this time, the low elongation yarn had a birefringence of 0.055 and an elongation of 123%, and the high elongation yarn had a birefringence of 0.010 and an elongation of 295% (Table 1).

Example 1 was repeated except that the temperature of the second hot roller 4 was set to 120 ° C. and the draw ratio was set to 1.48.
(Experiment No. 11). The physical properties are shown in Table 5, which shows that the high elongation yarn shows spontaneous elongation, and the low elongation yarn also has good shrinkage stress and high elongation characteristics. In addition, there was no yarn sway or yarn breakage during stretching, and the yarn could be produced without any problem. The success rate of restart after Doff was also good. In addition, it was of high quality with almost no staining spots.

[0034]

[Table 5] Example 5 Spinning was performed under the same conditions as in Example 1 except that the low elongation yarn was a high-shrinkage PET containing no titanium oxide and copolymerized with 8.0 mol% of IPA having an intrinsic viscosity of 0.66 and 3.5 mol% of BHPP. . Low elongation yarn has a birefringence of 0.040 and elongation of 88%, and high elongation yarn has a birefringence of 0.037 and an elongation of 17
6% (Table 1).

Example 1 was repeated except that the temperature of the second hot roller 4 was set to 120 ° C. and the draw ratio was set to 1.20.
The stretching was performed under the same conditions as in (Experiment No. 12). The physical properties are shown in Table 6. It can be seen that the high elongation yarn shows spontaneous elongation, and the low elongation yarn also has good shrinkage stress and good elongation characteristics. Furthermore, the shrinkage rate of the shrinkable yarn was significantly higher than that of Example 1, and a shrinkage difference mixed fiber having a more swelling feeling was obtained. In addition, there was no yarn sway or yarn breakage during stretching, and the yarn could be produced without any problem. The success rate of restart after Doff was also good. In addition, it was of high quality with almost no staining spots.

[0036]

[Table 6] Example 6 Experiment no. 300 turns /
m was twisted, and plain weaving was carried out with a zokki. This is dyed after 10% alkali weight loss by the usual method,
Dry heat setting was performed. The obtained fabric was soft and spontaneously stretched yarn emerged on the surface of the fabric, had a swelling feeling, and was also excellent in resilience.

[0037]

By using the mixed fiber of the present invention,
It is possible to produce a shrinkage difference mixed yarn or false twisted yarn excellent in swelling, softness and resilience in an extremely simple process.

[Brief description of the drawings]

FIG. 1 is a diagram showing a stretching device.

[Explanation of symbols]

 1: undrawn yarn 2: feed roller 3: first hot roller 4: second hot roller 5: cold roller 6: drawn yarn

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) D02J 1/22 D02J 1/22 N // D01D 5/08 D01D 5/08 5/34 5/34

Claims (5)

[Claims] 1. A mixed fiber comprising a low elongation yarn and a high elongation yarn, wherein the low elongation yarn is made of polyester, the high elongation yarn is provided with polyester in a sheath portion, and the core portion is sheathed. A mixed fiber yarn comprising a core-sheath composite yarn in which a polymer having a higher temperature dependence of elongational viscosity than a polyester is disposed. 2. The mixed fiber yarn according to claim 1, wherein the polymer disposed in the core of the high elongation yarn is a polystyrene-based polymer. 3. The mixed yarn according to claim 1, wherein the difference in elongation between the low elongation yarn and the high elongation yarn is 80% or more. 4. The composition according to claim 1, wherein the composite ratio of the polymer disposed in the core of the high elongation yarn is 2 to 5% by weight.
The mixed fiber according to any one of the above. 5. The mixed fiber yarn according to claim 1, wherein the low elongation yarn is made of a high shrinkage polyester.