JPH01156533A - Polyester false twisted crimped yarn - Google Patents

Abstract

PURPOSE: To obtain a polyester false-twisted crimped yarn that comprises thick and thin multifilament yarns, has specific values of thick part share, thick part density, stretch elongation and the thick/thin ratio and gives the fabrics cotton-like feeling of uneven appearance, a soft puff and harshness. CONSTITUTION: The yarn 4 fed from the package 6, as it is pulled out by the feed roller 5, is shrunk with heat on the first heater 7, then drawn between the first delivery roller 8 and the drawing roller 9, and subjected to a false- twisting texturing process by means of a second heater 10 and a false twister 11 and wound up in the package 13. Thus, the objective false-twisted finished thick and thin yarn having the thick part 1 share of 5-20%, the thick part share of 20-40% in the longitudinal direction of the filaments constituting the multifilament yarn, the thick part density of >=1.36 g/cm<3> of the multifilament yarn and the stretch elongation of 5-20% and the thick/thin ratio of >=1.20, is obtained.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention has irregular thickness unevenness in the longitudinal direction of the yarn, which gives the fabric a clearly uneven appearance, a soft bulge, and a smooth texture. It has a certain cotton-like texture.

This invention relates to a polyester false-twisted crimped yarn from which a woven or knitted fabric suitable for mid-summer wear can be obtained.

(Prior Art) Conventionally, polyester false-twisted yarn having uneven thickness in the longitudinal direction of the yarn has been produced by incompletely stretching an undrawn yarn, for example, as disclosed in Japanese Patent Publication No. 36051/1983. It is obtained by false-twisting the yarn, which has uneven thickness, but since this processed yarn has many thick parts with low density in an unstretched state, it is warped.

It is easy to cause thread breakage and fluff during knitting and weaving.

It becomes brittle due to post-processing such as alkali reduction and dyeing.

There was a drawback that the strength such as the tear strength of the fabric was reduced.

On the other hand, to eliminate the above drawbacks, 2 examples.

Japanese Patent Publication No. 58-7728 proposes a yarn in which highly oriented undrawn yarn, so-called POY, is incompletely stretched to form uneven thickness, and a textured yarn obtained by false twisting this yarn. There is.

However, in this processed yarn, the thick portions rarely overlap between the filaments constituting the multifilament yarn, resulting in less uneven thickness, and it was not possible to express clear unevenness on the fabric.

In addition, since these processed yarns have strong crimp, even if they are made into a single-knit fabric, they are required to be a synthetic fiber material suitable for mid-summer wear, which is the object of the present invention. A soft, crisp texture similar to cotton could not be obtained.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned drawbacks, and eliminates yarn breakage and fuzzing during the weaving and weaving process and its preparation process.
In addition, it does not become brittle during post-processes such as dyeing, and
It also has an uneven appearance.

A technical object of the present invention is to provide a polyester false-twisted crimped yarn that can yield a knitted fabric with a cotton-like texture that is soft and fluffy and suitable for mid-summer wear.

(Means for Solving the Problems) As a result of intensive studies to solve the above problems, the present inventors have determined the proportion of thick portions, the dispersion degree and density of thick portions in multifilament yarns, The present invention was achieved by discovering that the degree of crimp and the ratio of thick to thin can be set within a specific range.

In other words, the present invention is a false twisted 1'6 silk yarn made of polyester multifilament having uneven thickness, in which the thick portion occupancy rate in the longitudinal direction of the single filament constituting the multifilament yarn is 5 to 20%, and the multifilament The occupancy rate of the thick part in the longitudinal direction of the yarn is 20 to 40%, the density of the thick part of the multifilament yarn is 1.36 g/cm3 or more, the expansion/contraction ratio is 5 to 20%, and the thick/thin ratio is 1.20. The gist of the present invention is to provide a polyester false-twisted crimped yarn characterized by the above characteristics.

The present invention will be explained in detail below.

Firstly, in the polyester false twisted crimped yarn of the present invention, the thick portion occupancy in the longitudinal direction of the single filament constituting the multifilament yarn must be in the range of 5 to 20%, preferably 8 to 15%. .

If the thick part occupancy rate in the longitudinal direction of the single filament is less than 5%, the absolute amount of the thick part is small, so a sufficient thickness flame effect cannot be obtained, and the mJ of the multifilament yarn, which will be described later. A cotton-like texture cannot be obtained due to shrinkage.

On the other hand, the thick part occupancy rate in the longitudinal direction of the single filament is 20%.
If it exceeds 1, the deformation rate of the thick part increases during the false twisting process to obtain the yarn of the present invention, and as a result, the thick part becomes elongated.
The difference in the occupancy of the thick portion causes a difference in yarn length between the filaments, which results in a slimy feel, which is far from the crisp texture that is the objective of the present invention.

In addition, in yarns having uneven thickness, if the density of the thick part becomes too low, there will be various problems in practical use, so it is necessary to control the density of the thick part. However, in order to control the density of the thick part, G-coat is needed.

Even if an attempt is made to measure the density of the thick part of a single filament using the density gradient tube method or other methods, it is impossible to measure it because the diameter of the filament is small and short.

However, according to experiments conducted by the present inventors, the density of the thick part of the Tsuji multifilament yarn can be easily measured using the density gradient tube method, and furthermore, this thick BISO density is 1.36 g/
It was found that there is no problem in practical use when the number x has a value of cm3 or more.

If the density of this thick part is less than 1.36g/cm', it is necessary to warp.

It is easy to cause thread breakage and fluff during knitting and weaving.

When alkali weight loss is applied, the thighs are eroded and become brittle.

Furthermore, the fabric of the finished product has the disadvantage of being easily abraded, making it difficult to put it into practical use.

As in the present invention, when the density of the thick part of the multifilament yarn is 1.36 g/cm3 or more, no yarn breakage or fuzz occurs during the preparation process such as warping or the weaving and weaving process, and
It can also withstand alkaline weight loss.

Furthermore, there is no problem of the fabric of the product being worn out.

Next, in the polyester false twisted crimped yarn of the present invention, the thick portion occupancy rate in the longitudinal direction of the multifilament yarn is 20 to 4.
It is necessary to satisfy the range of 0%, preferably 25 to 35%.

Thick part occupancy rate of multifilament yarn in longitudinal direction is 20%
If it is less than 1, there will be less thick part in the yarn.

For this reason, the surface of the fabric will look dirty if only the protrusions are scattered on the fabric obtained by knitting and weaving.
It is not possible to obtain a crimped yarn that can provide the cool feeling that is the objective of the present invention.

On the other hand, when the thick part occupancy rate in the longitudinal direction of the multifilament yarn exceeds 40%, there are too many thick parts in the yarn, and therefore it does not appear that there are many convex parts on the fabric. ,
Rather, the crimped yarn appears to be dotted with concave portions, and a crimped yarn that can provide a refreshing feeling cannot be obtained.

The thick part occupancy rate of the multifilament yarn in the longitudinal direction is 20~
40% is the object of the present invention for the first time.

A crimped yarn can be obtained that can give the appearance of a cool uneven pattern in which many thick parts exist as handles in the details.

Furthermore, the polyester false twisted crimped yarn of the present invention is as follows.

It is necessary that the expansion/contraction/elongation ratio satisfies a range of 5 to 20%.

If the stretch/elongation rate is less than 5%, the crimp effect will be lost, resulting in a so-called green tea-like texture, and a soft, fluffy texture will not be obtained.

On the other hand, when the expansion/contraction rate exceeds 20%, the crimp of the filament becomes high, and the difference between the thick part and the details appears small.

For this reason, when making fabric, even if the thread thickness ratio is 1.2
Even if it is 0 or more, an uneven feel, a crunchy feeling, and a refreshing feeling cannot be obtained.

The polyester false twisted crimped yarn of the present invention is formed so that the positions of the thick parts between the single filaments are almost the same, so that the thick and thin parts of the single filaments are fully utilized, and the ratio between the thick parts and the details of the multifilament yarn is The thick-to-fine ratio is 1.20 or more.

If the thickness ratio is less than 1.20, there will be little unevenness in the fabric, so that it will not be possible to obtain an uneven feeling, a crisp feeling, or a cool feeling to the touch.

Next, two false twisted crimped polyester yarns of the present invention will be explained with reference to the drawings.

FIG. 1 shows nine yarns of the present invention separated and pasted on a mount. In the present invention, the thick portion occupancy in the longitudinal direction of a single filament is the ratio of the length of the thick portion 1 to the total length of the single filament.

The thick portion occupancy in the longitudinal direction of the single filament constituting the yarn of the present invention is 5 to 20%.

In addition, the thick section occupancy in the longitudinal direction of the multifilament yarn refers to the thick section of the multifilament yarn.

In other words, it is the ratio of the length of the part 2 (the shaded part) where a relatively large number of thick parts 1 of the single filaments constituting the multifilament yarn are gathered. The part occupancy rate is 20 to 40%. In Figure 1, 3 is a monofilament with few thick parts.
This is a part that is considered a detail.

In the case of the present invention, a portion where four or more thick portions of a single filament are gathered together is referred to as a thick portion.

Next, an example of the method for manufacturing the polyester false twisted crimped yarn of the present invention will be described.

The yarn of the present invention can be manufactured in two ways, for example, in one way.

A highly oriented undrawn polyester yarn spun at a spinning speed of about 3.500 m/min is used as a supply system, and the yarn is subjected to shrinkage heat treatment while intermittently contacting a hot plate or vibrating in a non-contact state, Causes shrinkage spots on the threads.

Following the above-mentioned shrink heat treatment, the yarn was
After stretching to double, (8,000 to 18,000) /
The false-twisted polyester of the present invention is subjected to false-twisting and crimping with a false-twisting number of V' [r (T/M), and has clear thickness irregularities, a soft crisp feel, and a cotton-like texture. Obtain shrunken thread.

In addition, when performing the shrink heat treatment on the yarn, any method other than the above may be used as long as it is a shrink heat treatment method that generates shrinkage spots on the yarn.

Also, when false-twisting yarn with uneven thickness.

The thick portions of the filaments that make up the yarn have a lower degree of orientation than the finer details, so they are more likely to be torsionally deformed. For this reason, when false twisting is performed at a number of false twists close to the twisting limit, the thick portion is elongated and thickness unevenness is reduced. However, if the phase of the thick part is aligned, the twist will be inserted in the details. For this reason.

The crimp form and thickness irregularity form change depending on the degree of gathering of thick parts, the number of false twists, and other processing conditions.

As a result of investigating this relationship, the present invention has developed a thick part phase.

By setting the stretch/elongation ratio within a specific range, it is possible to produce a false twisted crimped yarn that has clear thickness unevenness and a soft crisp feel at the same time.

Next, the above manufacturing method will be explained with reference to the drawings.

In FIG. 2, the pan cage 6 is
The supply system 4 pulled out from the yarn is subjected to a shrink heat treatment in a vibrating state caused by the vibration of the first heater 7 and a vibration device (not shown) or the running yarn itself.

Next, after being stretched to a predetermined stretching ratio between the first delivery roller 8 and the stretching roller 9, it is false-twisted and crimped by the second heak 10 and the false-twisting tool 11, and then passed through the second pre-heli roller 12. 1 Polyester provisional 1 of the present invention!
[It is wound up into package I3 as silk thread.

Next, a method for measuring physical property values defined in the present invention will be explained.

First, what is the thick portion occupancy in the longitudinal direction of the single filament that constitutes the multifilament yarn in the present invention?

It was calculated as follows.

100 mm of yarn was collected under a load of 0.1 g/d, separated into filaments, and each filament was pasted on a black mount under a load of 0.1 g/d. 0.5m11 which can be judged as the thick part of
The length of one or more thick portions is measured, and the ratio of the length of the thick portion to the measured length of each single filament is calculated. This measurement was performed at 10 arbitrary locations.

The average value of the ratio of the length of this thick portion is defined as the thick portion occupancy (%) in the longitudinal direction of the single filament.

Further, the thick portion occupancy rate in the longitudinal direction of the multifilament yarn was calculated in a first-order manner.

The part where four or more thick parts of the single filaments that make up the multifilament yarn are gathered together is called a thick part.

The length of the thick portion is measured along the longitudinal direction of the yarn, and the ratio of the length of the thick portion to the measured yarn length is defined as the thick portion occupancy (%) in the longitudinal direction of the multifilament yarn.

Here, the measured yarn length was 1,000 mm, and the average value of the thick section occupancy of five arbitrarily sampled yarns each having a yarn length of 1,000 mm was taken as the thick section occupancy in the longitudinal direction of the multifilament yarn.

Furthermore, the elasticity elongation rate was determined by the elasticity measuring method specified in JIS L-1090, and the sample used was one that had been heat treated (boiling x 30 minutes) and air-dried.

Next, when calculating the thick-to-thin ratio, first apply a load of 0.1 g/d to the multifilament yarn, and then
Five 200 mm twisted yarns of VT (17M) were collected.

The diameter of the thick part and the small part of each yarn is measured five times each, and the average diameter of the thick part and the small part is calculated. The average diameter of the thick part and the detail of these five yarns is calculated, and the value obtained by dividing the average diameter of the thick part by the average diameter of the detail is defined as the thick/fine ratio.

(Example) The present invention will be explained in more detail below using two examples.

Example 1.2 230d obtained by spinning at a spinning speed of 3.500 m/min
A highly oriented undrawn polyethylene terephthalate yarn of /48f was processed under various conditions according to the process shown in FIG. 2 to obtain a false twisted crimped yarn.

Table 1 shows the processing conditions and the physical properties of the crimped yarn obtained.

Table 1 Furthermore, as Comparative Example 6, the spinning speed was approximately 800 m/min.
Polyethylene terephthalate undrawn yarn 440 spun with
d/24f was subjected to tension heat treatment with steam at 70°C for 10 minutes, then cold-stretched to 2 times and then false-twisted to 1,100 T/M.
.

False twisting was performed at a false twisting temperature of 170° C. and a false twisting overfeed rate of 0%. The processed yarn obtained in Comparative Example 6 is as follows.

Single filament thick part occupancy 19%, multifilament yarn thick part occupancy 35%, stretch elongation rate 18%, large/thin ratio 45. The density of the thick part was 1.350 g/cm3.

Using these processed yarns, the warp density is 64/2.54c.
m.

After weaving into a plain weave with a weft density of 60 threads/2.54 cm,
The weight was reduced by 8% by alkali treatment, and a plain white fabric was obtained.

Table 2 shows the evaluation results of the obtained fabric.

Table 2 (Effects of the Invention) Since the polyester false twisted crimped yarn of the present invention has the above-mentioned structure, the ratio of the thick part and the dispersion state are appropriate, and when this crimped yarn is used for weaving and knitting, the thick part The part appears as a convex pattern and is slightly crimp, so it can be used in midsummer with a soft bulge and crispness without diminishing the visual and sensory effects of the convex pattern on the fabric. A suitable woven or knitted fabric can be obtained.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the dispersion state of the thick portion of the polyester false twisted crimped yarn of the present invention, Fig. 2 is a schematic process diagram showing an example of the manufacturing method of the yarn of the present invention; Thick part 2 is the thick part of the multifilament yarn. Patent applicant Unitika Co., Ltd.

Claims (1)

[Claims] (1) A false twisted crimped yarn made of polyester multifilament having uneven thickness, where the thick portion occupancy rate in the longitudinal direction of the single filament constituting the multifilament yarn is 5 to 5.
20%, the occupancy rate of the thick part in the longitudinal direction of the multifilament yarn is 20 to 40%, and the density of the thick part of the multifilament yarn is 1.36 g/cm^3 or more, and the expansion/contraction rate is 5.
20% and a thick-to-fine ratio of 1.20 or more.