JP2003055846A - False-twisted yarn and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a false-twisted yarn having excellent stretchability and softness and provide a method for producing the yarn. SOLUTION: The false-twisted yarn is composed of a multifilament polyester yarn. Essentially all filaments constituting the yarn are side-by-side conjugate fibers composed of polytrimethylene terephthalate A and polyethylene terephthalate B and the false-twisted yarn satisfies the formula: 50<= (the lateral pressure recovery rate of the yarn %) <=80. The method for the production of the false-twisted yarn comprises the false-twisting of a highly oriented undrawn polyester multifilament yarn having an elongation of 100-250% and composed of polytrimethylene terephthalate A and polyethylene terephthalate B conjugated in a side-by-side state while drawing the undrawn yarn at a draw ratio of 1.2-2.0.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a false twisted yarn excellent in stretchability and softness and a method for producing the same.

[0002]

2. Description of the Related Art Heretofore, as a polyester fiber excellent in elastic recovery property and suitable for a stretch material, for example, JP-A-1
Japanese Patent Application Laid-Open No. 1-93026 proposes a polyester false twisted yarn having polytrimethylene terephthalate as a main polymer component. This processed yarn is certainly excellent in elastic recovery, but it has a strong feeling of roughness due to crimping and a high hot water shrinkage ratio, so that the fabric such as the fabric lacks a soft texture.

Japanese Unexamined Patent Publication No. 2000-256925 proposes a polyester false twisted yarn which contains polytrimethylene terephthalate as a main polymer component and is subjected to a relaxation heat treatment continuously after a one-step heater false twist. However, the softness of the fabric was insufficient because the stretchability was emphasized.

Further, Japanese Unexamined Patent Publication No. 2000-256918 also investigates a method of false-twisting by combining main polymer components of polytrimethylene terephthalate having different copolymerization ratios in a side-by-side type. According to this method, a fabric excellent in stretchability and elastic recovery can be obtained, but the softness is still insufficient, and the use of polytrimethylene terephthalate also deteriorates the dimensional stability.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a false twisted yarn having a stretchability, an elastic recovery property and a soft texture, and a method for producing the same, by solving the problems of the prior art. It is intended.

[0006]

In order to achieve the above object, the present invention adopts the following configurations. That is, a false twisted yarn of a polyester multifilament yarn, wherein the filament yarn that constitutes the false twisted yarn includes a fiber in which polytrimethylene terephthalate A and polyethylene terephthalate B are combined in a side-by-side type,
The false twisted yarn is characterized in that the yarn side pressure resistance recovery rate satisfies the following formula.

50 ≦ yarn side pressure resistance recovery rate (%) ≦ 80 or a polyester-based multifilament highly oriented undrawn yarn having an elongation of 100 to 250%, which is a side-by-side composite of polytrimethylene terephthalate A and polyethylene terephthalate B. A method for producing a false twist textured yarn, which comprises false twisting while drawing at a draw ratio of 2 to 2.0.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the textured yarn of the present invention, a fiber obtained by side twisting a side-by-side type composite of polytrimethylene terephthalate (PPT) A and polyethylene terephthalate (PET) B is finely twisted to obtain a fine crimped product. Processed yarn can be obtained. As a result, it is possible to obtain a smooth and soft cloth exhibiting a high degree of stretchability and exhibiting no wrinkles.

When polytrimethylene terephthalate A and polyethylene terephthalate B are made into a side-by-side type highly oriented undrawn yarn, they have latent crimping property due to the difference in elastic recovery rate and shrinkage property thereof. When this latent crimp is stretched, strain is generated in the single fiber, and a form of coil crimp is generated. In the present invention, the crimped pitch is made finer by false-twisting this fiber at the same time, so that not only high stretchability but also soft cloth can be obtained.

At this time, it is preferable to dispose the polytrimethylene terephthalate A inside the coil crimp because the recovery property upon repeated stretching is improved and a comfortable stretch repulsion feeling is obtained.

FIG. 1 illustrates the false twisted yarn of the present invention. The false twisted textured yarn of the present invention does not have a three-dimensional rough crimp like the conventional false twisted textured yarn but has a fine pitch crimp, so that single filaments are unlikely to cause steric hindrance with each other. It becomes a wavy shape. Therefore, mutual shrinkage and restraint in the cloth are reduced, so that the stretch expression amount in the cloth is increased.

[0012] A commonly used shrinkage measurement, for example JI
Even if the crimping performance of the yarn can be grasped by the measurement of the expansion and contraction recovery ratio described in SL 1090, it was not necessarily linked to the stretchability when the cloth was made into it. Since the space for expressing the crimp is unlimited, it cannot be assumed that the fabric is under constraint, and therefore the stretchability of the fabric cannot be judged.

In the present invention, the concept of the yarn side pressure resistance recovery rate is used as an index for evaluating the stretchability in the fabric. The yarn side pressure resistance recovery rate is, as described later, a measuring method in which the glass tube undergoes crimping under lateral pressure. In this measuring method, the coarse crimp, which is likely to be restrained in the cloth, is restrained by lateral pressure to make it difficult for the crimp to develop. By measuring this yarn side pressure resistance recovery rate, the stretchability of the actual fabric can be evaluated. Further, the fact that the yarn side pressure resistance recovery rate shows a high value also means that the surface of the processed yarn is smooth, so that the softness can also be evaluated. If the yarn side pressure resistance recovery rate is less than 50%, the crimp is in a rough state, and the fabric lacks stretchability and softness. Further, when the yarn side pressure resistance recovery rate exceeds 80%, the fabric becomes grainy.

In addition, the false twisted yarn of the present invention has an excellent elastic recovery performance at a relatively low stress and a low strain amount due to a fine crimped form, and also has a polytrimethylene terephthalate molecular structure even in a high strain region. Due to its structural elasticity, stretch performance with high resilience and power is achieved.

Further, in the present invention, since polyethylene terephthalate is contained in the component, the pleating property, which is a weak point in polytrimethylene terephthalate, becomes good.

Among the polyesters of the present invention, polytrimethylene terephthalate A is a polyester obtained by using terephthalic acid as a main acidic component and 1.3 propanediol as a main glycol component.

Other copolymerizable components capable of forming an ester bond may be contained within a range that does not impair the effects of the present invention, preferably 20 mol% or less, more preferably 10 mol% or less. Examples of the copolymerizable compound include dicarboxylic acids such as isophthalic acid, succinic acid, cyclohexanedicarboxylic acid, adipic acid, dimer acid, and sebacic acid, while the glycol component includes, for example, ethylene glycol-
Examples thereof include, but are not limited to, ethylene glycol, butenediol, butanediol, neopentyl glycol, cyclohexane dimethanol, polyethylene glycol and polypropylene glycol.
Further, titanium dioxide as a matting agent, fine particles of silica or alumina as a lubricant, a hindered phenol derivative as an antioxidant, a color pigment and the like can be added as required.

The composite ratio of the components A and B of the present invention is preferably 8: 2 to 2: 8 by weight. Outside of this range, the amount of either component A or B will decrease, and the crimping will become rough. A more preferable composite ratio is 6: 4 to 4: 6.

In the present invention, the filaments forming the false twist textured yarn include a side-by-side type composite fiber of polytrimethylene terephthalate A and polyethylene terephthalate B.

In the present invention, it is preferable that substantially at least the cross-sectional shape of the filament is a modified cross section having a quadrangle or more, and the polymer boundary line of the cross section is a curve.

In the case of false-twisting a filament having a round cross-section, which is often used in the past, a close-packed structure is adopted in the twisting zone, so that the cross-section is almost entirely hexagonal.
When the cross-sectional shape consists of irregular cross sections of square or more,
Each filament has a crimped form with a different appearance,
Since the mutual crimping is less likely to interfere with each other, crimping is likely to occur in the fabric. Also, by making it a different shape, it will have a smooth texture like nylon.

Further, since the polymer boundary line of the cross section is a curve, the shapes of the polymers are made asymmetrical, and more coil shrinkage is exhibited.

Alternatively, it is preferable that the single-filament filament has a flat cross-sectional shape and the following expression is satisfied.

20 ≤ flatness (%) ≤ 80 flatness (%) = (D2 / D1) x 100 D1: length of major axis in single filament filament cross section D2: maximum of minor axes orthogonal to D1 The length of the monofilament filaments herein means that the cross-sectional shape of the single-filament filament is flat, and the flatness ratio derived from the ratio of the lengths of the major axis and the minor axis of the cross section is 20
% Or more and 80% or less. As shown in FIG. 2, its specific shape is (a) elliptical, (b) mushroom-shaped,
Any shape may be used as long as it is a flat type such as (C) dogbone type and (D) shell type. In FIG. 2, PP
T indicates polytrimethylene terephthalate A, PET
Represents polyethylene terephthalate B.

If the single-filament filament has a flat cross-sectional shape, the phase of the fine pitch crimp of each single-filament filament is shifted, so that the cloth can be made smoother and softer.

When the oblateness exceeds 80%, it cannot be said that the oblateness is flat and the crimp phase shift effect cannot be expected. On the other hand, if it is less than 20%, the fabric tends to be irritated, which is not preferable.

The total fineness of the false twisted yarn of the present invention is 3
It may be appropriately selected within the range of 0 Dtex to 1000 Dtex according to the purpose of use. Single yarn filament fineness is
0.5 to 10d for both strength and soft touch
It is preferably tex, more preferably 1.5 to
It is 6 dtex.

Next, a method for producing the false twist textured yarn of the present invention will be described. The false twisted textured yarn of the present invention is a polyester-based multifilament highly oriented undrawn yarn having an elongation of 100 to 250%, which is a composite of polytrimethylene terephthalate A and polyethylene terephthalate B in a side-by-side type.
It is characterized in that false twisting is performed while stretching at 2 to 2.0 times.

The drawing step at this time may be a drawing simultaneous false twisting carried out at the same time as the false twisting as shown in FIG. 3 (a), or as shown in FIG. 3 (b). A pre-stretched false twist in which pre-stretching is performed using the heat pin 8 before twisting may be used.

At this time, if the draw ratio is less than 1.2 times, the strength / elongation property is not satisfied, and if it exceeds 2.0 times, fluff tends to occur. The false twisted yarn of the present invention has a strength of 3.
It is preferably 0 cN / dtex or more.

When the substantial filaments constituting the polyester are only polytrimethylene terephthalate A, if the false twist is carried out at a temperature of 150 ° C. or higher, the strength and elongation will decrease. Therefore, the false twisted yarn has an insufficient heat setting effect as compared with the false twisted yarn mainly containing polyethylene terephthalate B.

In the present invention, a polyester in which polytrimethylene terephthalate A and polyethylene terephthalate B are side-by-side type is used.
False twisting can be performed in a high temperature zone of 150 ° C to 200 ° C to enhance the heat setting effect.

When the false twisting temperature is lower than 150 ° C., the heat setting effect is insufficient and it is difficult to obtain sufficient crimping. On the other hand, when the temperature exceeds 200 ° C., fusion occurs and a yarn having an untwisted portion but having a rough texture is obtained, and strength and elongation, crimping, and recovery of structural elasticity are also insufficient.

As the side-by-side composite die of the present invention, known ones can be used.

Next, after being discharged from the composite spinneret, a highly oriented undrawn yarn is obtained and subjected to false twisting simultaneously with drawing. This false twisting process may be either a single heater method or a two heater method. The false twist number TW (T / M) at false twist is 2200.
The range of 0 / (D) ^{1/2 to} 39000 / (D) ^1/2 is preferable. When it is less than 22000 / (D) ^1/2 , it is difficult to impart sufficient crimping, while 39000 /
When (D) is more than ^1/2 , the frequency of occurrence of fluff and broken yarn of the processed yarn increases. More preferably 26000 / (D)
^{1/2 to} 36000 / (D) ^1/2 (where D is fineness and decitex).

As the false twisting device, any false twisting device such as a friction false twisting device and a fluid false twisting device can be used, but friction false twisting using a friction disk is preferable.

Post-entanglement may be performed by using an entanglement nozzle after false twisting.

The false twisted textured yarn of the present invention is a known composite false twisting means such as simultaneous false twist, phase difference false twist, elongation difference false twist with polytrimethylene terephthalate fiber or other fiber yarns, if necessary. A composite false twisted yarn may be obtained according to. The false twist textured yarns of the present invention, or various original yarns and textured yarns may be interlaced, interlaced, taslan-processed, or twisted. Further, reheat setting may be performed after false twisting.

[0039]

The present invention will be described in more detail with reference to examples, but the present invention is not limited to the examples. The measured values in the text and Examples were detected by the following methods.

(1) Recovery rate of yarn side pressure resistance (%) A skein is obtained under a tension of 90 mg / dtex with a measuring machine having a circumference of 0.8 m. Total decitex at that time was 2600
Adjust the number of windings so that it is closest to (dtex). Then, the obtained cassette is passed through a glass tube having an inner diameter of 3.65 mm. One end of the cassette is gripped by the glass tube, a load of 150 g is applied to the other end, and the cassette is cut at the glass tube outlet on the side where the load is applied. The cassette cut into the length (L) of the glass tube is subjected to hot water treatment at 90 ° C. for 3 minutes while being put in the tube, and the length (L1) after the contraction is expressed under the lateral pressure of the tube is measured. The yarn side pressure resistance recovery rate is calculated by the following formula.

Thread side pressure resistance recovery rate (%) = {(L-L1)
/ L} × 100 (2) Flatness Paraffin embedding method, 3 cross-section samples of the processed yarn are collected. Then, the obtained cross-section sample is magnified 800 times with a microscope, and a photograph is taken with a video printer. From that, the long axis D1 and the short axis D2 of the cross section are calculated at 5 points per sample, 15 points in total, and the flatness is calculated by the following formula from the average thereof.

Flatness (%) = (D1 / D2) × 100 (3) Fabric stretch rate It was measured according to JIS-L-1096.

The present invention will be specifically described below with reference to examples. The evaluations in the examples were performed by the following methods.

(1) Evaluation of Softness The softness of the woven fabric obtained by the method described in Examples and Comparative Examples was sensory-evaluated by touch. At this time, Comparative Example 1 which is a conventional product
Using the woven fabric of No. 2 as a standard, the following criteria were used to perform a five-level evaluation, and the evaluation results of 10 panelists were averaged for the judgment. 5: Extremely soft texture 4: Slightly soft texture 3: Texture equivalent to standard woven fabric 2: Slightly hard texture 1: Extremely hard texture.

(2) Evaluation of surface quality The surface quality of the woven fabric obtained by the method described in Examples and Comparative Examples is
Sensory evaluation was performed by touch. At this time, the woven fabric of Comparative Example 1 which is a conventional product was used as a standard, and a five-level evaluation was performed according to the following criteria, and the evaluation results of 10 panelists were averaged and judged. 5: Extremely good surface quality 4: Slightly good surface quality 3: Surface quality equivalent to standard woven fabric 2: Slightly poor surface quality 1: Extremely poor surface quality FIG. 3A shows the false twisting process of the present invention. It is a schematic diagram showing an example of a manufacturing process of a thread. The multifilament 1 passes through the feed roller 2, is false-twisted by a twisted body (false-twisting tool) 5, is introduced into the first heater 3, is heat-set, and is cooled by the cooling plate 4. Then, it is taken up by the take-up roller 7 via the delivery roller 6. Further, FIG. 3B is a schematic view showing an example of a manufacturing process in which the multifilament 1 is pre-stretched by the heat pin 8 and then false-twisted.

Example 1 Polytrimethylene terephthalate and polyethylene terephthalate having a circular cross section were mixed at 5: 5.
Side-by-side composite with a composite ratio of 150 dte
A highly oriented undrawn yarn having x, 36 filament elongation of 175% was used.

Using the false twisting process shown in FIG. 3A, false twisting was carried out under the conditions shown in Table 1 to obtain a false twisted yarn. The cross-section of the obtained processed yarn was composed of irregular cross-sections of quadrangle or more, the shape was 8 squares, 13 pentagons and 3 hexagons, and the polymer boundary line of the cross section was curved. (See Figure 5). Further, it was found that the flatness was 80% and the yarn side pressure resistance recovery rate was 58.8%, and that there was sufficient crimping expression power even when the fabric was restrained. The obtained processed yarn is further twisted at 500 T / m in the S direction to be used as a weft yarn, and 56 Dtex, 24 filament polyethylene terephthalate drawn yarn (twisted at 250 T / m in the S direction) is used as a warp, and a rapier loom is used. Was woven with a 3/1 twill to form a woven fabric. Continue to relax scouring with hot water at 97 ℃, 120 with Terrasil navy blue disperse dye
The fabric was obtained by dyeing at ℃ and finishing heat setting at 160 ℃. This fabric had a woven fabric stretch ratio of 72%, the highest stretchability and soft touch. In addition, the surface quality of the fabric was good because the shrinkage was fine.

(Embodiment 2) Elongation 1 obtained by combining side-by-side type polytrimethylene terephthalate and polyethylene terephthalate having a mushroom type cross section at a compounding ratio of 5: 5.
A 72% highly oriented undrawn yarn was subjected to false twisting under the conditions of Table 1 using the same false twisting process as in Example 1 to obtain a false twisted yarn.

The cross section of the obtained textured yarn was flat and the flatness was 50% (FIG. 5). Further, it was found that the yarn side pressure resistance recovery rate was 56.9%, and that there was a sufficient crimping force even when the fabric was restrained. The obtained textured yarn was woven and dyed under the same conditions as in Example 1. The obtained fabric had a woven fabric stretch ratio of 68%, high stretchability, and soft touch. In addition, the fabric was smooth and had a fine crimp, so the surface quality was good.

Comparative Example 1 Two kinds of polytrimethylene terephthalate having different viscosities of 1.5 and 0.8:
150 dt composited side-by-side with a composite ratio of 5
An ex, 36 filament, stretched yarn with an elongation of 30% was used.

The yarn side pressure resistance recovery rate of the obtained textured yarn is 4
The resistance was large, probably because there was a lot of rough crimping at 4.6%. Weaving the obtained textured yarn under the same conditions as in Example 1,
Dyeing was performed. The resulting fabric has a fabric stretch ratio of 54%
It had a slightly insufficient stretchability, the surface had a rough texture, and the softness was insufficient.

Comparative Example 2 150 dtex, 36 filaments of polytrimethylene terephthalate, elongation 160
% Highly oriented undrawn yarn was used.

The yarn side pressure resistance recovery rate of the obtained textured yarn was 6
The resistance was high, probably because there was a lot of rough shrinkage of 5.3%.

The obtained textured yarn was woven and dyed under the same conditions as in Example 1. The obtained cloth did not have satisfactory stretchability with a woven fabric stretch ratio of 47%. Moreover, the surface had a rough texture and was not soft enough.

[0055]

[Table 1]

[0056]

As described above, the false twisted textured yarn of the present invention is a false twisted textured yarn having stretchability, elastic recovery property and soft texture.

The textured yarn of the present invention exhibits a high degree of stretchability and exhibits smoothness and softness without wrinkles by exhibiting fine pitch crimp diameter crimp expression in the fabric without losing the constraint in the fabric. A fabric can be obtained.

In addition, the combination of polytrimethylene terephthalate and polyethylene terephthalate not only has good elastic recovery characteristics and pleat characteristics, but also has a large difference in shrinkage characteristics between the two, which results in a crimped pitch. Can be made finer, and a soft drapeable cloth can be obtained.

When the cross-sectional shape is a square, pentagonal, or hexagonal cross-section, it has a nylon-like smooth texture, and since the polymer boundary line of the cross-section is a curve, more coil Ken is obtained. Shrinkage begins to develop.

When the cross-sectional shape is flat, the cloth can be made smoother and softer.

Further, since it has excellent stretch characteristics, especially in sports clothing, the fabric can sufficiently follow the stretch, and the occurrence of cracks on the elbows and knees can be suppressed.

Further, in the present invention, since the side-by-side type yarn is in a highly oriented undrawn yarn state, the coil crimp peculiar to the side-by-side type yarn is supplied in a latent state. Therefore, the raw yarn can be released without any problem with the creel, and the process passability is excellent.

By simultaneously false-twisting the highly oriented undrawn yarn, the processing speed can be set to 400 m / min or more, which is also excellent in terms of production efficiency.

The fabric made of the false twisted yarn of the present invention is used for clothing, particularly outerwear such as jackets and bottoms, ladies' clothing such as dresses, skirts, arm warmers and stockings, jerseys, athletic wear, ski wear, leotards and the like. It can be used as a stretch material for sports clothing, stockings, tights, socks, innerwear such as underwear, and industrially used towels, umbrellas, interlinings, toothbrushes, fishing lines, ropes, artificial grass, car seats and the like.

[Brief description of drawings]

FIG. 1 is a side view showing an example of a false twist textured yarn obtained by the present invention.

FIG. 2 is a schematic view showing an example of a flat cross section.

FIG. 3 is a schematic view showing an example of a processing step for obtaining a processed yarn of the present invention.

FIG. 4 is a schematic cross-sectional view of a textured yarn obtained in Example 1.

5 is a schematic sectional view of a textured yarn obtained in Example 2. FIG.

[Explanation of symbols]

1: Multifilament 2: Feed roller 3: First heater 4: Cooling plate 5: twisted body 6: Delivery roller 7: Take-up roller 8: Heat pin

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Claims (2)

[Claims] 1. A false twisted yarn of a polyester-based multifilament yarn, wherein the filament yarn constituting the false twisted yarn includes a fiber in which polytrimethylene terephthalate A and polyethylene terephthalate B are combined in a side-by-side type. A false twisted yarn having a yarn side pressure resistance recovery rate satisfying the following formula. 50 ≦ yarn side pressure resistance recovery rate (%) ≦ 80 2. A polyester-based multifilament highly oriented unstretched yarn having a elongation of 100 to 250%, which is a composite of polytrimethylene terephthalate A and polyethylene terephthalate B in a side-by-side type, while being drawn at a ratio of 1.2 to 2.0. A method of manufacturing a false twisted textured yarn, which comprises false twisting.