JPH05247714A - Production of bulky textured yarn - Google Patents

Abstract

PURPOSE:To obtain synthetic fiber yarn having physical properties sufficiently enough for use as clothes, having extremely low stress, especially low stress under low load. CONSTITUTION:Polybutylene terephthalate is subjected to melt spinning, not wound once, immediately drawn and the prepared drawn yarn is subjected to false twisting processing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a textured yarn having a soft texture and made of polybutylene terephthalate.

[0002]

BACKGROUND OF THE INVENTION Stretchable yarns are used in various fields including clothing applications, and such yarns are made of elastic polymers such as elastomers,
Bulky crimped yarns such as false twisted yarns are often used.

However, those made of an elastic polymer generally have a problem that the physical properties of the fiber are not sufficient and the use thereof is limited. Therefore, for the use of clothing, excellent fiber physical properties such as polyester, nylon and polybutylene terephthalate are used. It is performed to impart crimp to the yarn to have a stretch property by false twisting or the like. However, ordinary polybutylene terephthalate and nylon false twisted yarns have high shrinkage,
For example, in the spinning / drawing process of winding a paper tube, the paper tube is crushed during the winding operation and the winding shape is collapsed, which makes production difficult.

Further, when an interlining material for clothing is obtained by using such a yarn, it is generally used by adhering it to the outer material. At this time, in order not to kill the texture of the outer material, Those with low stress are desired. Conventionally, as a material related to the interlining, a low stress material using a polyester crimped yarn is known in JP-A-62-97937.

[0005]

However, even with the above-mentioned conventional techniques, a sufficiently low stress yarn cannot be obtained yet. The present invention is to solve such a problem, and its purpose is to have sufficient physical properties for use in clothing, and among synthetic fiber processed yarns known in the related art,
An object of the present invention is to provide a synthetic fiber yarn having an extremely low stress and, in particular, a low stress under a low load.

[0006]

The present invention provides a false twisting process for a drawn yarn obtained by melt spinning polybutylene terephthalate and immediately drawing it without winding it once.

The polybutylene terephthalate used in the present invention contains butylene terephthalate as a repeating unit in an amount of at least 90 mol% or more, and additionally contains a third component such as polytetramethylene glycol or diethylene glycol. Good. Such polybutylene terephthalate can be produced at a known temperature of 270 ° C.
It is melted in a certain degree and spun.

Usually, after the synthetic fiber yarn is spun by the melt spinning method, the molecular structure is stabilized by leaving it (aging) or stretching it. In the case of the present invention,
After the melt spinning, a drawing process is carried out by a so-called direct spinning drawing method in which a drawing process is carried out immediately without being wound up once, and a drawn yarn is obtained. The direct spinning / drawing method itself is known, and is disclosed in JP-A-1-2.
There are many disclosures such as Japanese Patent Publication No. 21505, and these methods can be used in the present invention.

The present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing an example of a direct spinning and drawing method. In FIG. 1, molten polybutylene terephthalate 1
The powder is spun from the die 2, passed through the cooling device 3 and the oiling roller 4, drawn by the first godet roller 5, then drawn between the first godet roller 5 and the second godet roller 6, and wound up by the package 7.

The take-up speed of the first godet roller 5 is preferably about 1700 to 2000 m / min.
The draw ratio between the godet roller 5 and the second godet roller 6 is preferably about 1.75 to 1.95 times. If the stretch ratio is greatly deviated from such a range, the stress becomes high when the stretch ratio is high, or the shrinkage ratio becomes high and the paper tube is crushed when the stretch ratio is low. There is a risk.

The polybutylene terephthalate drawn yarn thus obtained has a length of 50 cm immediately after spinning at 25 ° C.
When left in an atmosphere of 60% for 2 hours, its length is measured and the desorption rate is calculated by the following equation, the rate is 0.6% or less, and the self-shrinkage rate is extremely low.

[0012]

[Equation 1] However, l ₀ = original length, l ₁ = length after leaving

Next, in the present invention, such a polybutylene terephthalate stretched yarn is subjected to false twisting treatment. The false twisting method may be a known method, but in the present invention, the spindle false twisting method is preferable to the friction false twisting method because the residual elongation of the yarn is low, and the false twisting temperature is 170 to 190 ° C. This is preferable because a false twisted yarn having a low degree of stress can be obtained. Further, the number of false twists is preferably in the range of the following formula in order to increase the crimp rate, and under such processing conditions, a false twist processed yarn having a crimp rate of about 60 to 70% can be obtained.

[0014]

[Equation 2] However, D is the fineness (denier)

The polybutylene terephthalate bulky yarn obtained as described above has an extremely low stress of 50 mg / d or less when stretched by 10% under a low load. Also, the boiling water shrinkage rate is relatively low at 2.5% or less.

Such a polybutylene terephthalate bulky yarn is made into a woven or knitted fabric, particularly a woven fabric, which is used as an interlining coated with a thermoplastic resin in a dot shape and is attached to another highly stretchable woven fabric or the like. By wearing it, a high quality fabric is obtained. When used for such an application, the single yarn fineness of the polybutylene terephthalate bulky processed yarn is 0.5 to
About 3d is preferable, and the cover factor of the fabric is 800.
It is preferably about 1200.

[0017]

[Function] Generally, the stress of polybutylene terephthalate is
It is known that it is lower than polyester and the like, but if it is obtained by a usual spinning winding process and a normal twisting process (conventional method), it does not yet become a sufficiently low stress yarn. On the other hand, the present inventors have found that the stress of the yarn obtained by the direct spinning and drawing method is lower than that in the conventional method. That is, in the conventional method, the undrawn yarn is usually left to stand (aging) for a while after the winding of the spinning yarn, but during this period, the crystal structure grows, which causes the crystal structure to grow. It is speculated that it may increase stress.

In the present invention, the polybutylene terephthalate is stretched immediately after spinning to stop the growth of the crystal structure as described above, so that stress can be obtained even though it is a stretched yarn.
This is a yarn with a low rate of release.

[0019]

EXAMPLE A polybutylene terephthalate drawn yarn was spun as follows using the apparatus shown in FIG. That is, 90% or more of the repeating units are butylene terephthalate,
2 polybutylene terephthalate 1 with an intrinsic viscosity of 0.82
It is melted at 70 ° C, discharged from the die 2, cooled and solidified by the cooling device 3, then taken up by the first godet roller 5 at 60 ° C rotating at 1850 m / min, and further 3400 m / m.
The film was stretched by 1.84 times with the second godet roller 6 of 109 ° C. rotating at in and wound on the package 7 (Example 1).

On the other hand, the same polybutylene terephthalate was melt-spun, taken up at 1500 m / min and wound into a package to obtain an unstretched yarn (Comparative Example 1), which was allowed to stand at room temperature for 10 hours and then placed in a twisting machine. And drawn 2.24 times to obtain a drawn yarn (Comparative Example 2).

Further, polyethylene terephthalate having an intrinsic viscosity of 0.64 in which 95% or more of the repeating unit is ethylene terephthalate was melted at 290 ° C. and stretched in the same manner as in Example 1 (Comparative Example 3), Comparative Example 1 Unstretched yarn (Comparative Example 4) obtained in the same manner as in (1) and drawn (Comparative Example 5)
Prepared.

These drawn yarns were placed on a spindle type false twisting machine (LS-6, manufactured by Mitsubishi), and polybutylene terephthalate had a false twisting speed of 85 m / min, a heater temperature of 190 ° C.
A false twist number of 4550 T / M, polyethylene terephthalate was processed at a false twist rate of 102 m / min, a heater temperature of 205 ° C. and a false twist number of 3800 T / M, and wound on a paper tube to obtain a false twist crimped yarn. The results are shown in Table 1.

[0023]

[Table 1]

As shown in Table 1, the polybutylene terephthalate spun by the spin draw method has an extremely low stress at 10% elongation. Further, the desorption rate is also reduced to the level of polyethylene terephthalate by using the spin draw method. Therefore, in Example 1 and Comparative Examples 3 to 5, the bulky processed yarn could be wound up by the paper tube, but Comparative Examples 1 and 2
The paper tube was crushed during winding, and the paper tube could not be wound.

Furthermore, the bulky processed yarn 50 obtained in Example 1
Using d / 24f, weave a plain woven fabric with a warp of 82 yarns / inch and a weft of 64 yarns / inch, and apply an olefin resin in a dot shape with a diameter of 0.7 mm to the polyester twill and attach it to the outer material. When used as a stretchable interlining material, it had a soft texture.

[0026]

Industrial Applicability According to the present invention, a polybutylene terephthalate bulky processed yarn having extremely low stress under a low load can be obtained. Therefore, when this yarn is used as an interlining for clothes, etc., it has a soft texture and high stretchability. It is possible to manufacture a product having Further, the present invention is capable of producing such a bulky processed yarn with high productivity.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of a direct spinning drawing method used in the present invention.

Claims (1)

[Claims] 1. A method for producing a bulky textured yarn, which comprises subjecting a drawn yarn obtained by melt-spinning polybutylene terephthalate and then immediately stretching without winding it, to false twisting.