JP2001226832A - Polyester conjugate fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-class woven or knitted fabric having sufficiently quality feeling, and comfortable stretch-back properties without using a polyurethane-based fiber-yarn, and further having soft feeling, a large bulking and resilience while eliminating the fault of a conventional technique. SOLUTION: This polyester conjugate fiber is a side-by-side type conjugate fiber consisting of (A) a highly viscous polyester component and (B) a lowly viscous polyester component, and is characterized by >=7.0 peaks/cm number of crimps after a boiling water treatment, and the rate of the crimps, the number of the crimps and the shrinkage of the fiber, satisfying the following formulas: 2.0<=X/Y<=6.0; and 1.5<=Z<=10.0 (wherein, X is the rate of the crimps after the boiling water treatment; Y is the number of the crimps (peaks/cm) after the boiling water treatment; and Z is the shrinkage (%) of the fiber).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester composite fiber having a crimping property, and more particularly to a polyester composite fiber in which two-component polyesters having different viscosities are combined in a side-by-side type. The present invention relates to a polyester composite fiber which has excellent stretch-back properties when extruded, has excellent surface quality, and has high swelling and resilience and can be used as a high-grade woven or knitted fabric.

[0002]

2. Description of the Related Art In general, synthetic fibers such as polyester and polyamide are widely used for clothing and industrial purposes because of their excellent characteristics. Above all, polyester fibers are widely used from apparel to industrial use because of their excellent functions such as strength, dimensional stability, and easy care property.

For example, there is a method in which polyurethane-based fibers are mixed into a woven fabric to impart stretchability. However, polyurethane-based fibers have a property that the texture is hard as a property inherent to polyurethane, and there is a problem that the texture and softness of the fabric are reduced. Furthermore, polyurethane fibers are hardly dyed by polyester dyes, and even when used in combination with polyester fibers, not only the dyeing process becomes complicated, but also it is difficult to dye to a desired color.

Japanese Patent Application Laid-Open No. Hei 3-307924 discloses a method for imparting stretchability to a woven fabric by subjecting polyester fiber to false twisting and using a fiber having a twisting / untwisting torque. However, this torque has a problem that the woven fabric surface tends to transfer to the grain, and the woven fabric tends to be defective. For this reason, a torque balance is achieved by heat treatment or S / Z twist to balance the stretchability and the defects caused by the grain formation, but the problem is that the stretchability is generally too low. .

[0005] For this reason, as a method not using a polyurethane fiber or false twisted yarn, various polyester composite fibers composited in a side-by-side type have been proposed. These have been studied variously as measures for improving the stretchability in order to increase the value of the crimp rate or the number of crimps.
For example, in Japanese Patent Application Laid-Open No. 5-295670, a side-by-side conjugate fiber having a good crimp ratio after boiling water treatment is produced by using a highly shrinkable copolymer PET as a high-viscosity polyester component and a low-shrinkage RegPET as a low-viscosity polyester component. A method is disclosed. However, the copolymer P
Although the side-by-side type conjugate fiber using ET has good crimp characteristics, there is a problem that the fiber shrinkage is large and a soft feeling cannot be obtained.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to overcome the drawbacks of the prior art and to provide a comfortable stretch-back property without using polyurethane filaments, especially when used for high-quality woven or knitted fabrics. Also, the present invention relates to a polyester composite fiber which is excellent in surface quality and can be used as a high-grade woven or knitted fabric having both a large swelling and resilience.

[0007]

An object of the present invention is to provide a side-by-side conjugate fiber comprising a high-viscosity polyester component (A) and a low-viscosity polyester component (B),
This is achieved by a polyester composite fiber characterized in that the number of crimps after boiling water treatment is 7.0 peaks / cm or more, and the crimp rate and the number of crimps after boiling water satisfy the following formula. I can do it.

2.0 ≦ X / Y ≦ 6.0 1.5 ≦ Z ≦ 10.0 where X is the percentage of crimp after boiling water treatment (%) Y is the number of crimps after the boiling water treatment (peak / cm) ) Z is the fiber shrinkage (%)

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The polyester conjugate fiber of the present invention needs to be a side-by-side type conjugate fiber composed of a high-viscosity polyester component (A) and a low-viscosity polyester component (B).
That is, crimps are developed by combining polymers having different viscosities in a side-by-side type, and stretchability can be imparted.

The polyester composite fiber of the present invention has a crimp rate X (%) after the boiling water treatment and a crimp number Y (mountain / c) after the boiling water treatment.
It is necessary that the relationship X / Y of m) satisfies the following expression. 2.0 ≦ X / Y ≦ 6.0 The polyester composite fiber of the present invention needs to have a crimp number after boiling water treatment of 7.0 peaks / cm or more. If the number of crimps after the boiling water treatment is less than 7.0 peaks / cm, stretchability and resilience are lost,
It does not meet the purpose of the present invention.

X / Y indicates the size of the crimp diameter of the crimp, and the relationship between the crimp ratio X (%) after the boiling water treatment and the number of crimps Y (peak / cm) after the boiling water treatment is defined as 2. 0 ≦ X / Y ≦
By setting the value to 6.0, when the fabric is used, high stretchability can be exhibited, and a smooth and high-grade surface quality can be obtained. When X / Y exceeds 6.0, the number of crimps is too small relative to the crimp rate, and the crimp diameter becomes too large, so that the fabric cannot have a smooth surface feeling. On the other hand, when X / Y is less than 2.0, the crimp becomes coarse, so that surface quality is improved, but bulkiness and softness are reduced. Further, it is preferable that 3.0 ≦ X / Y ≦ 4.5 in order to keep good surface quality and stretch back property.

The crimp ratio X (%) after the treatment with boiling water defined in the present invention is determined by the method described below. The side-by-side conjugate fiber, which has been lapped 10 times with a measuring machine, is subjected to a boiling water treatment at 100 ° C. for 30 minutes in a free state. Thereafter, the sample is air-dried for 30 minutes, a load of 2.27 × 10 ⁻³ cN / dtex is applied, and the length a is measured. Then 2.27 × 10 ^-3 cN
After removing the load of / dtex, the length b is measured while applying a load of 5.6 × 10 ⁻³ cN / dtex. Then, it is obtained from the following equation. Crimp rate (%) = [(ba) / b] × 100.

The number of crimps Y (peaks / cm) after the boiling water treatment defined in the present invention is determined by the following method. First, a sample cut to a length of 7 cm is subjected to boiling water treatment at 100 ° C. for 15 minutes in a free state. Next, as soon as it is taken out, it is treated with cold water for 1 minute and then naturally dried for 5 hours. The dried sample is stuck on a sample plate, covered with a slit plate having a width of 1 cm, transferred to a screen with a projector, and the number of peaks is read. The measurement is performed twice for each of 10 samples, and the average is defined as the number of crimps.

The polyester composite fiber of the present invention needs to have a fiber shrinkage Z (%) of 1.5 ≦ Z ≦ 10.0%. By setting the fiber shrinkage Z at 1.5% or more and 10.0% or less, a soft feeling can be obtained in addition to bulkiness, tension, waist, and resilience. When the fiber shrinkage Z exceeds 10.0%, the shrinkage of the woven or knitted fabric itself becomes large, so that a coarse stiffness becomes apparent. Conversely, when the fiber shrinkage Z becomes less than 1.5%, the bulkiness and rebound of the woven or knitted fabric are felt. Is impaired.

The fiber shrinkage defined in the present invention is determined by the following method. First, the hank of the composite fiber of 10 turns in test scale machine under a load of 3.5 cN / dtex, to measure the original length L _0. Next, the load is removed, and 100
Treat with boiling water at 15 ° C for 15 minutes. Immediately after taking out, it is treated with cold water for 1 minute, and then naturally dried for 5 hours. Measuring a post-processing length L ₁ wait 30 seconds over the load. It is calculated from the following equation.

Fiber shrinkage (%) = [(L ₀ −L ₁ ) / L ₀ ] × 100 The polyester composite fiber of the present invention has a single-fiber fineness of 2.5 to 2.5.
It is preferably 6.0 dtex. The softness and resilience can be further improved by setting the single yarn fineness within the above range.

The high-viscosity polyester component (A) and the low-viscosity polyester component (B) of the polyester composite fiber of the present invention.
The composite ratio of A: B is preferably 70:30 to 40:60 in order to further improve crimp development, and in order to simultaneously improve the toughness of the yarn, the composite ratio A: B = 60. : 40 to 50:50.

The high-viscosity polyester component (A) and the low-viscosity polyester component (B) constituting the polyester composite fiber of the present invention are terephthalic acid or its lower alkyl derivative (alkanol diester having 1 to 4 carbon atoms) and ethylene. Glycol or from terephthalic acid or a lower alkyl derivative thereof with ethylene glycol and at least one other component, or bis-2.
-Hydroxyethylene terephthalate or a low polymer thereof, or a polyester in which at least 70% of polyester units obtained from bis-2-hydroxyethylene terephthalate and at least one other component are polyethylene terephthalate.

In this case, as the third component, for example, oxalic acid,
Aliphatic dicarboxylic acids such as adipic acid, azelaic acid and sebacic acid; aromatic dicarboxylic acids such as isophthalic acid, phthalic acid, 2-6 naphthalene dicarboxylic acid and diphenic acid;
Dicarboxylic acids having an alicyclic ring, such as 2-cyclobutanedicarboxylic acid, and the like, but are not limited thereto.

Next, a method for producing the polyester composite fiber of the present invention will be described. In the method for producing a conjugate fiber of the present invention, a high-viscosity polyester component (A) and a low-viscosity polyester component (B) are bonded in a side-by-side type using a predetermined composite pack and a composite die using a commercially available composite spinning machine. Composite spinning is performed to obtain an undrawn yarn. At this time, the high-viscosity polyester component (A) and the low-viscosity polyester component (B)
Can be obtained by adjusting the discharge amount. Also,
The intrinsic viscosity difference [ΔIV] of both polymers can be freely selected depending on the polymer used. However, if the viscosity difference is too large, the crimping characteristics are good, but the discharge bend becomes large due to the flow velocity difference between the two components immediately below the die discharge hole, and yarn breakage occurs frequently during spinning. Therefore, ΔIV is 0.40 or less. And even 0.
It is preferably 30 or less. Conversely, if the difference in viscosity is too small, the spinning properties are improved, but the crimp development is reduced.
Is preferably 0.15 or more, more preferably 0.20 or more. Here, the intrinsic viscosity is a value measured in orthochlorophenol at 25 ° C. Using this undrawn yarn, it is possible to obtain a polyester composite fiber by drawing it with a normal drawing machine so as to have a predetermined elongation at break. In addition, breaking elongation is 10.0-40.0.
% Is preferable. When the content is within this range, a yarn having good spinnability and good crimping properties can be obtained.

The polyester composite fiber of the present invention may be used alone for warp and weft as it is, or may be used after being mixed with other yarns. In addition, false twisting may be applied, or false twist may be mixed. In addition, a real twist may be provided, a real twist may be mixed, or any combination thereof may be used, and any method that exerts the characteristics of the composite fiber of the present invention may be used.

A woven or knitted fabric is produced by using the polyester composite fiber of the present invention, and alkali reduction treatment can be suitably used for women's materials. In addition, in sports applications, in particular, the alkali weight reduction treatment may be properly used depending on the application. The woven or knitted fabric thus obtained has excellent surface quality, further has stretchback properties, and produces a new luxurious woven or knitted fabric that could not be obtained by the conventional technology having both a large swelling and resilience. can do.

[0023]

The present invention will be described below in detail with reference to examples. 1. Product texture A sensory evaluation was conducted by five skilled persons, mainly based on stretchback properties and bulkiness, taking into account moderate tension, waist, resilience, and softness. ○○: Excellent ○: Good △: Acceptable ×: Not possible Yarn-making properties The following judgment method was used. ○: Thread breakage rate is less than 3.0% ○: Thread breakage rate is 3.0% or more and less than 6.0% △: Thread breakage rate is 6.0% or more and less than 10.0% ×: Thread breakage rate is 10.0% or more-: Evaluation not possible Higher workability Judged from the yarn breakage of the weaving machine during weaving. ○: The yarn breakage of the weaving machine is less than 3.0% ○: The yarn breakage of the weaving machine is 3.0% or more and less than 6.0% △: The yarn breakage of the weaving machine is 6.0% Or more and less than 10.0% ×: The yarn breakage rate of the weaving machine is 10.0% or more.

Example 1 As a high-viscosity polyester component (A) consisting of 100% polyethylene terephthalate (PET), [IV] was 0.1%.
750 polyethylene terephthalate, PET100
% Of low-viscosity polyester component (B) [IV] composed of 0.530% and a composite ratio of 50:50, and a composite spinning in a side-by-side type at a winding speed of 1750 m / min. I got This undrawn yarn is subjected to a drawing heat setting so as to have a residual elongation of 30.0% and a fiber shrinkage of 4.0%.
A 12 fil drawn yarn was obtained. Table 1 shows the physical properties of the obtained drawn yarn.
Shown in Next, a plain woven fabric was prepared using the obtained drawn yarn as the weft and a normal polyester filament yarn (56 dtex-12 fil) as the warp, followed by refining, intermediate setting, and alkali reduction to obtain a fabric.

The obtained plain woven fabric (Level 1) had excellent stretch-back properties and bulkiness, tightness and waist, resilience, and softness, and was a luxurious fabric. Next, the polymer specifications were changed to obtain levels 2 to 4. In the case of the level 2, the yarn-making properties were slightly inferior to those of the level 1, but excellent crimping properties were obtained. Level 3 had good spinnability and high processability, but had insufficient crimping characteristics due to a small difference in polymer viscosity. Further, at the level 4, the crimping property at the raw yarn level was good, but the spinning property was poor.

In the side-by-side type conjugate fiber shown here, the conjugate interface state is not necessarily linear due to the difference in viscosity of the two-component polyester used, and the conjugate interface state and spinning / drawing conditions are appropriately corrected depending on the polymer specifications used. Table 1 shows the evaluation results.

[0027]

[Table 1]

Example 2 An experiment was carried out in accordance with Level 1 of Example 1 except that the fineness of single yarn was changed as shown in Table 2. Levels 5 and 6 had the desired stretch back properties, bulkiness, and softness, and also had good spinning properties and high processing properties.

Level 7 is an experiment in which the fineness of a single yarn was 2.0 dtex. The fineness of the fine yarn slightly deteriorated the tension and resilience, but the softness and the stretchback property were good. . Level 8 is an experiment in which the single-fiber fineness was 7.5 dtex, but the single-fiber fineness was slightly large, so that the softness was slightly inferior, but the resilience, yarn-making properties, and high-order workability were good. Table 2 shows the evaluation results.

[0030]

[Table 2]

Example 3 An experiment was carried out in accordance with Level 1 of Example 1 except that the composite ratio of the high viscosity component and the low viscosity component was changed as shown in Table 3. Level 9 is an experiment in which the high-viscosity polyester component was increased to 70%, and was excellent in stretchback properties and bulkiness, and also excellent in spinning properties and high passability. Level 10 is an experiment in which the high-viscosity component was reduced to 40%. Although both the spinning property and the product texture were slightly inferior to Level 1, the stretchback properties and softness were good.

Level 11 was an experiment in which the composite ratio of the high-viscosity polyester component was 75%. The stretch-back property and the thread property were slightly good, but the bulkiness was not high.

Level 12 was an experiment in which the composite ratio of the high-viscosity polyester component was 35%, and the yarn production was good, but the texture of the product was poor. Table 3 shows the evaluation results.

[0034]

[Table 3]

Example 4 In the production of the composite yarn of level 1 in Example 1, the heat setting temperature and the draw ratio were changed to obtain levels 13 to 16. Level 13 is an experiment in which the heat setting temperature and the draw ratio were set so that the fiber shrinkage ratio was 10.0%.
It was also excellent in bulk height and resilience. Level 14 is an experiment conducted under the conditions set so that the fiber shrinkage rate is 1.5%, and a result almost equivalent to Level 13 was obtained.
Level 15 is an experiment conducted by setting conditions so that the fiber shrinkage rate is 13.5%. The stretch back property and the bulk height are good, but the fiber shrinkage rate is too large, so that a soft feeling is obtained. It was missing. Level 16 is an experiment conducted by setting the conditions such that the fiber shrinkage rate is 1.0%. However, since the fiber shrinkage rate is too small, the crimping property is reduced and the stretchback property is lacking. there were. Table 4 shows the evaluation results.

[0036]

[Table 4]

[0037]

EFFECTS OF THE INVENTION It is made of polyester conjugate fiber and has good yarn-making properties, has a comfortable stretch-back property without using polyurethane yarns when used for woven or knitted fabric, and has a soft feeling, large swelling and resilience. It is possible to obtain a high-grade woven and knitted fabric that has both functions.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4L041 AA08 BA02 BA05 BA09 BA59 BC04 BC05 BC17 BD14 BD20 CA06 DD01 DD04 4L045 BA21 BA36

Claims (3)

[Claims] 1. A side-by-side conjugate fiber comprising a high-viscosity polyester component (A) and a low-viscosity polyester component (B), wherein the number of crimps after boiling water treatment is 7.0 peaks / cm or more; A polyester composite fiber having a crimp rate, a number of crimps, and a fiber shrinkage rate after a boiling water treatment satisfying the following expressions. 2.0 ≦ X / Y ≦ 6.0 1.5 ≦ Z ≦ 10.0 where X is the crimp rate (%) after the boiling water treatment Y is the number of crimps after the boiling water treatment (peak / cm) Z is Fiber shrinkage (%) 2. The polyester composite fiber according to claim 1, wherein the single yarn fineness is 2.5 to 6.0 dtex. 3. The composite ratio of the high viscosity polyester component (A) and the low viscosity polyester component (B) is 70:30 to 40:
The polyester composite fiber according to claim 1, wherein the number is 60.