JP2003221736A - Polyester semidrawn yarn - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester semidrawn yarn capable of not only improving characteristics of ultrafine fibers but also overcoming disadvantages thereof and having excellent yarn processability. <P>SOLUTION: This polyester semidrawn yarn is splittable conjugated fibers having 60-250% residual elongation and composed of a polyester A in which a main constituent component is a polyester and a polyester B prepared by copolymerizing isophthalic acid or its derivative having a metal sulfonate group so as to provide a higher alkali weight reduction rate than that of the polyester A and 0.3-0.8 wt.% of S fraction. The polyester A has no straight-line part in the cross-sectional shape. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester semi-stretched yarn, and more specifically, excellent color development, soft and suede-like touch can be obtained, and characteristics can be easily diversified by performing composite processing with other fibers. The present invention relates to a polyester semi-drawn yarn which is excellent in yarn forming property and yarn processability.

[0002]

2. Description of the Related Art The history of synthetic fibers begins with imitation of natural fibers, and in recent years, not only simple imitation of natural fibers but also characteristics unique to synthetic fibers and comfort more than natural fibers have been demanded.

As a technique for obtaining a particularly soft texture, Japanese Patent Laid-Open Nos. 62-78213 and 1-260 have been proposed.
The method of using ultrafine fibers by the splittable conjugate fiber proposed in Japanese Patent Application Laid-Open No. 018 and Japanese Patent Application Laid-Open No. 1-272861 is widely known. Although it is possible to obtain the soft feeling, peach feeling, and suede feeling peculiar to the ultrafine fibers by these methods, there is a problem that the obtained fabric has poor elasticity and firmness and poor color developability.

As a technique for improving the firmness and firmness, Japanese Patent Laid-Open No. 6-184928 proposes a technique for supplementing the firmness and firmness by mixing fibers with thick fibers having a single yarn fineness. With such a mixed fiber technology, the firmness and elasticity are improved, but unevenness occurs due to the difference in dyeability between the mixed yarns, and as a means for solving this, a difference in shrinkage is given to both yarns,
Although a method of imparting entanglement has been shown, it is necessary to increase the shrinkage ratio of a thick yarn having a single yarn fineness in order to give a shrinkage difference, so that not only there is a problem that the feeling of coarseness of the fabric increases
It is not possible to diversify the fabric properties by imparting other properties such as stretchability and repulsion, and the problem of color development found in ultrafine fibers has not been solved.

[0005] In order to diversify the fabric characteristics, a method of compounding a semi-stretched yarn with other fibers is known, and a wide range of properties are imparted depending on the processing method and the type of other fibers used in processing. However, the splittable conjugate fiber is a composite of a component that is easily eluted in an alkaline aqueous solution and a component that is difficult to dissolve, and a semi-drawn yarn is obtained from the poor orientation of the component that is easily eluted in the alkaline aqueous solution. At that time, there was a problem that the strength was remarkably lowered, and the yarn formability and the yarn processability were lowered.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is not only to enhance the soft and suede-like touch which is a feature of a fabric made of ultrafine fibers, but also to its disadvantage of low color development.
Improvement of glare, firmness and elasticity by combining with other fibers,
An object of the present invention is to provide a polyester semi-stretched yarn which has improved resilience deficiency and can be easily imparted with other properties, and which suppresses the irritating feeling associated with compounding, and has stable spinnability and yarn processability.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide polyester A whose main constituent is polyester and a faster alkali weight loss rate than the polyester, and an S fraction of 0.3.
A split-type conjugate fiber having a residual elongation of 60 to 250%, which is composed of a polyester B copolymerized with isophthalic acid or a derivative thereof having a metal sulfonate group so as to be 0.8 to 0.8% by weight. Can be achieved by a polyester semi-drawn yarn characterized by having no straight portion in the cross-sectional shape.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below.

The polyester semi-drawn yarn in the present invention is
It is a splittable conjugate fiber composed of polyester A and polyester B having an alkali reduction rate difference in order to obtain ultrafine fibers. The ultrafine fibers have a single yarn fineness of 0.4.
A fiber composed of yarns of dtex or less is preferable. Further, the splittable conjugate fiber is a conjugate fiber that is split and finely divided by alkali reduction treatment, and the composite state and cross-sectional shape are not particularly specified as long as the object is achieved. With such a splittable conjugate fiber, it becomes possible to easily obtain an ultrafine fiber using existing spinning equipment.

Polyester B, which has a faster alkali reduction treatment rate than polyester A, is obtained by copolymerizing isophthalic acid having a metal sulfonate group or its derivative (hereinafter referred to as SIA) in order to facilitate alkali reduction. In order to easily elute the polyester B by the alkali reduction treatment, SIA was copolymerized so that the S content was 0.3% by weight or more. The S fraction in the present invention refers to the weight ratio of sulfur atom (S component) to all ester components in the corresponding polymer.

On the other hand, a polyester obtained by copolymerizing SIA tends to be difficult to be oriented during spinning because it has a bulky functional group, and the strength of the polyester semi-stretched yarn obtained by combining with the polyester tends to decrease. is there. Therefore, in the present invention, the polyester B has an S fraction of 0.
SIA is copolymerized so as to be 8% by weight or less, preferably 0.6% by weight or less. As SIA, dimethyl (5-sodium sulfo) isophthalate, bis-2-hydroxyethyl (5-sodium sulfo) isophthalate, bis-4-hydroxybutyl (5
Examples thereof include sodium sulfo) isophthalate and dimethyl (5-lithiumsulfo) isophthalate, with dimethyl (5-sodiumsulfo) isophthalate and bis-2-hydroxyethyl (5-sodiumsulfo) isophthalate being particularly preferred. Polyester A contains terephthalic acid as a main acid component and at least one selected from ethylene glycol, propylene glycol, butylene glycol, cyclohexane-1,4-dimethanol, pentamethylene glycol and hexamethylene glycol as a main glycol component. The polyester may be copolymerized with 20 mol% or less of the third component, as long as the object of the present invention is not impaired. Although the intrinsic viscosity (IV) of the polyester A is not particularly limited, it is preferably in the range of 0.60 to 0.90 in view of the spinnability of the polyester semi-drawn yarn, the thread processability and the ease of spinning. The intrinsic viscosity (IV) is measured by dissolving 0.1 g of a sample in 10 ml of orthochlorophenol and using an Ostwald viscometer at a temperature of 25 ° C.

Further, in the present invention, the residual elongation of the polyester semi-drawn yarn is 60% or more in order to facilitate the yarn processing alone or the compound processing with other materials. From the viewpoint of suppressing yarn breakage / fluffing and quality variation due to aging, it is 250% or less. A more preferable range of residual elongation is 80 to 200%. The ultrafine fibers obtained by processing such a polyester semi-drawn yarn can suppress the fiber orientation by being able to suppress the draw ratio to be low, and in addition to the good color developability, the Young's modulus becomes low, It is possible to get a soft touch.

In general, a cloth made of ultrafine fibers tends to have a glaring feeling due to its split state and yarn form. Therefore, from the viewpoint of suppressing light reflection, the polyester A has a straight line portion. However, as shown in FIG. 1, it is preferable that the cross-sectional shape of the polyester A indicated by reference numeral 1 is a round cross section.

Further, in order to enhance the reflection suppressing effect, it is preferable that the polyester A contains a matting agent in an amount of 0.3% by weight or more. On the other hand, excessive addition leads to deterioration of yarn formability and weavability, so it is preferable to set it to 7.0% by weight or less. As the matting agent used in the present invention, titanium oxide, zirconium oxide, magnesium oxide, aluminum oxide, silicon oxide, antimony oxide, zinc oxide, lead tungstate, calcium tungstate, calcium carbonate, etc. exhibit the effect of the present invention. Any one can be used as long as it can be stably dispersed in polyester, but titanium oxide, silicon oxide, zinc oxide, and calcium carbonate are preferable from the viewpoint of dispersibility. The average particle size is preferably 1 μm or less, more preferably 0.7, from the viewpoint of dispersibility.
μm or less. Furthermore, the maximum particle size is
It is preferably 5 μm or less, more preferably 3 μm or less.

The alkali reduction treatment in the present invention was performed by the following method. That is, the polyester fiber of the present invention was added to a 2% aqueous sodium hydroxide solution at a bath ratio of 1: 125 and a temperature of 98.
It is a method of treating at -100 ° C. The weight reduction rate is calculated by subtracting the weight after treatment from the weight before treatment, dividing the value by the weight before treatment, and multiplying by 100. The weight reduction rate is calculated from the weight reduction rate per unit time when the above weight reduction treatment is performed after fiberizing each polyester described in the present invention.

Further, the polyester semi-drawn yarn of the present invention is
A small amount of additives within a range of 10% by weight or less, for example, heat stabilizers, antioxidants, optical brighteners, ultraviolet absorbers, colorants,
You may add a hygroscopic agent, a bacteriostatic agent, a negative ion generator, etc.

The residual elongation is calculated by the following method. Using a Tensilon tensile tester manufactured by Toyo Baldwin Co., Ltd., a fiber with a sample length of 100 mm was stretched at a tensile speed of 400 mm / min until it was broken, and the length from the start of tension to the break was measured. The residual elongation is calculated by multiplying by 100.

The method for producing the polyester semi-drawn yarn of the present invention is not particularly limited, but a method of winding at a speed of 2500 m / min or more is preferable, and 2000 to 4500.
m / min is more preferable, and a method of adding an orientation suppressing agent or the like and winding up at a speed of about 5000 m / min may be mentioned.

[0019]

The present invention will be described in more detail with reference to the following examples. In addition, each characteristic value in the examples is obtained by the following method, the evaluation is measured by the method described in the present invention, and quantified, or excellent: ○○, excellent: ○, good: △, poor: × It was carried out in four stages. Further, the present invention is not limited to these examples. A. It was judged from the number of times of yarn breakage when obtaining the polyester semi-drawn yarn or the drawn yarn in the yarn formability example, and the superiority or inferiority comparison was performed according to the following criteria. Special: Less than 2.0 yarn breaks per 1000 kg of yarn production Excellent: 2.0 or more and less than 4.0 yarn breaks per 1000 kg of yarn production Good: 4.0 yarn breakage per 1000 kg of yarn production Not less than 6.0 times but less than 6.0 times: The number of yarn breakages per 1000 kg of yarn making is 6.0 times or more. Yarn processability It was comprehensively judged from the number of yarn breakages and the number of fluffs when the polyester semi-drawn yarn or drawn yarn obtained in the example was processed. C. Regarding the cloths obtained in the cloth quality examples, a skilled technician and a salesperson selected 6 regarding a disagreeable gloss feeling (hereinafter referred to as glaring), a soft feeling, and the presence or absence of irritatingness due to the difference in dyeing of different fibers. Sensory evaluation was performed by name.

Example 1 Polyester A comprising 2.0% by weight of titanium oxide in polyethylene terephthalate having an intrinsic viscosity [η] of 0.60 and polyethylene terephthalate having an intrinsic viscosity [η] of 0.54. It contains 0.1% by weight of titanium oxide and contains bis-2-hydroxyethyl (5-sodium sulfo) isophthalate (hereinafter referred to as SSIA) with an S fraction of 0.
Polyester B copolymerized to 45% by weight was compounded so that the weight ratio was 80:20, and the compounded state was as shown in FIG. It was discharged from the spinneret as described above. In the composite state shown in FIG. 1 below, the sea-island type composite polymer is cooled and solidified, and then a smoothing agent is added thereto, subjected to entanglement treatment, and spun by two take-up rolls at a speed of 3000 m / min. A polyester semi-drawn yarn of 100 dtex and 36 filaments was obtained. Subsequently, this polyester semi-stretched yarn is subjected to 15% overfeed, 84 dtex, 15 filaments, 15% boiling point,
A processed yarn was obtained by performing a composite false twist with a shrinkage yarn having a dry yield of 20%, and a plain woven fabric using this as a warp and a weft was woven. The cloth was subjected to an acid treatment, an alkali weight reduction treatment, and a raising treatment, and was subjected to a dry heat treatment at 180 ° C. for 15 minutes to be dyed to obtain a cloth for evaluation. Table 1 shows the results of evaluation of the yarn-forming property, yarn processability, and fabric quality of the polyester semi-drawn yarn.
The elongation in the table means the residual elongation described in the present invention.
The evaluation of the productivity in the yarn making and yarn processing was good, and the obtained fabric was free from glare and irritability and had a soft feeling.

Examples 2 to 4 and Comparative Examples 1 to 3 The same evaluation as in Example 1 was carried out by changing the copolymerization amount of SSIA in Polyester B in Example 1 as shown in Table 1. The obtained polyester semi-drawn yarn showed a tendency for the residual elongation to increase as the amount of copolymerization of SSIA was increased, but when it was excessively copolymerized, it reached a peak, and the spinnability tended to decrease slightly in Example 4. Indicated. Further, in Comparative Example 3, the yarn breakage occurred frequently due to the rubbing with the yarn guide, probably because the strength of the polyester semi-drawn yarn was significantly reduced. A similar tendency was observed in yarn breakage during yarn processing. The fabric quality was good in all Examples, but in Comparative Examples 1 and 2, polyester A did not split well, and Comparative Example 1 did not split at all, so a soft feeling was not obtained.

[0022]

[Table 1]

Examples 5 to 9 and Comparative Examples 4 to 5 Polyester semi-drawn yarns of Examples 5 to 9 and Comparative Example 5 were obtained by changing the spinning speed in Example 1 to 1500 to 4200 m / min. Comparative Example 5 in Example 4
A polyester stretched yarn was obtained by stretching the semi-stretched yarn obtained in (1). It should be noted that the polymer discharge amount is the same as in Example 1 and the processing magnification and overfeed rate during yarn processing are changed to obtain a processed yarn having a fineness and filament number substantially the same as in Example 1. Table 2 shows the results of evaluation of the same items as in Example 1 for the polyester fiber. The spinnability was good in all cases, but tended to decrease slightly as the spinning speed increased. Regarding the thread processability, the running state of the thread during processing tended to become unstable as the residual elongation increased, and in Comparative Example 5, the thread breakage tended to increase. No significant difference was found in the feeling of glare, but Example 5 had the best soft feeling,
Furthermore, the effect of improving the color developability was obtained. Further, the lower the residual elongation, the more the irritating feeling tended to increase. A cross-sectional photograph of the composite state of the processed yarn revealed that the higher the residual elongation of the polyester semi-drawn yarn, the more the yarn wraps around the shrinkable yarn. Therefore, the difference in dyeability between the two yarns It is considered that the annoyance caused by the noise was suppressed. Comparative Example 4 did not take such a form of covering the shrinkable yarn, and was a fabric with strong irritability.

[0024]

[Table 2]

Examples 10 to 15 In Example 1, the addition amount of titanium oxide was 0.0 to 10.
Table 3 shows the results of similar evaluations performed on the fabric obtained by changing the content to 0% by weight. By increasing the amount of titanium oxide added, the spinnability and thread processability tended to decrease, but the resulting fabric was more suppressed in the feeling of glare. Example 10 in which titanium oxide was not added at all
The glare tended to be stronger.

Comparative Example 6 In Example 1, the spinneret used during spinning was changed to obtain a polyester semi-drawn yarn having a composite state of a shape including a linear portion in the cross-sectional shape shown in FIG. 2, and the same evaluation was carried out. Although the yarn forming and yarn processability was good and no particular problems were observed, the fabric which was the object of the present invention could not be obtained because of the strong glare.

[0027]

[Table 3]

[0028]

Industrial Applicability According to the present invention, not only is the soft and suede-like touch characteristic of a fabric made of ultrafine fibers further enhanced, but the disadvantages thereof are low coloring, improvement of glare, and firmness and elasticity due to the combination with other fibers. Feeling, improved lack of resilience,
It has become possible to provide a polyester semi-drawn yarn in which other properties can be easily imparted, the irritability associated with compounding can be suppressed, and the spinnability and yarn processability are stable.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a polyester semi-drawn yarn in an example.

FIG. 2 is a cross-sectional view of a polyester semi-drawn yarn in a comparative example.

[Explanation of symbols]

1: Polyester A 2: Polyester B

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4L041 AA07 BA04 BA05 BA16 BC01                       BD12 CA05 CA12 DD11 EE06                       EE14

Claims (2)

[Claims] 1. A polyester A whose main constituent is polyester, and an isophthalic acid having a metal sulfonate group so that the alkali weight loss rate is higher than that of the polyester and the S fraction is 0.3 to 0.8% by weight, or an isophthalic acid thereof. A splittable conjugate fiber having a residual elongation of 60 to 250%, which is composed of a polyester B copolymerized with a derivative, wherein the polyester A has no straight portion in a cross-sectional shape. Polyester semi-drawn yarn. 2. A polyester A having a matting agent of 0.3 to 7.
The polyester semi-drawn yarn according to claim 1, characterized in that the content thereof is 0% by weight.