JPS6221823A - Production of spun yarn like processed yarn - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing spun yarn-like textured yarn having bulkiness, and more specifically, although it is a bulky yarn that utilizes the yarn length difference due to doubling and false twisting, The present invention relates to a method for producing a textured yarn with a spun yarn-like structure that has a stable crimped form and a soft texture through subsequent heat treatment and entanglement treatment.

There are many development examples of methods for producing textured yarns with bulkiness.Differences in yarn length occur when multiple yarns with different physical properties are drawn and twisted with gold yarn or double yarns are twisted, resulting in bulkiness. It is also well known that it can be obtained.

In addition, even if the yarn obtained from such bulky processed yarn has a spun-like soft touch (texture), it is difficult to make it into a woven fabric after additional twisting, especially medium twisting or strong twisting. Because it has a hard texture and is easy to tear, attempts have been made to increase the softness by combining yarns with low single yarn fineness as surrounding side yarns or by increasing the number of false twists. In addition, as a conventional general concept especially for yarns for textiles, it has been customary not to heat set them after false twisting.

This is because heat treatment after false twisting (two-stage heater treatment) reduces crimpability and causes loss of bulk, and heat treatment after false twisting is recommended for knitted fabrics that are not suitable for excessive crimp. It is said to be prescribed for yarns used in

However, as a result of our studies on various structured textured yarns for textiles, we have confirmed that a soft texture can be obtained by heat-treating bulky textured yarns with different yarn lengths after false twisting. Furthermore, by performing the entanglement treatment in the region between the heat treatment rollers, the crimp form becomes stable, the difference in yarn length is fixed, and the overall yarn is very similar to spun yarn and soft. It has been found that a yarn suitable for highly twisted woven fabrics can be obtained.

In the present invention, the key point is to heat-treat the plied false-twisted yarn with a yarn length difference of 10 inches or more at a temperature of 150° C. or higher, and the entanglement treatment is performed in this heat-treated region.

It is not clear why a soft fabric is obtained by this heat treatment and entanglement treatment after false twisting, but it is said that the second heat treatment makes it stable for processing heat treatment in the subsequent process, and that the torque is reduced. It is also expected that there will be some dispersion between the two. Also,
Entanglement processing in this region, especially entanglement processing under tension, clarifies the roles of the core yarn and side yarns, stabilizes the core yarn by reducing crimpability, and reduces yarn length differences due to continuous entanglement. This can be done by promoting fixation and dispersion between single yarns, resulting in a processed yarn that looks like spun yarn in terms of appearance and texture.

Furthermore, in the present invention, it has a soft texture or waist,
7. In order to obtain a bulky and soft fabric with less cut, it is necessary to increase the yarn length difference, make the single yarn fineness of the core yarn thicker, make the side yarn finer, and increase the yarn length. In order to increase the difference, decrease the torque, and increase the dispersion between single yarns,
This is done in combination with a high number of false twists due to high stretching.

Methods for creating structured yarns with such yarn length differences include a method of combining a plurality of yarns having different physical properties, and a method of applying yarn feeding differences to the same yarn. In either method, it is necessary that the yarn length difference between both core side yarns after false twisting is at least 10 inches; if it is less than this, the bulkiness is insufficient and it is difficult to obtain a soft spun yarn texture. The method for measuring the difference in yarn length is to separate both yarns after false twisting without performing entanglement treatment, measure the yarn length under a load of 0.2 g/d, and calculate the difference. is appropriate. However, if the entanglement treatment is performed first and the false twisting process is performed, it is expected that the yarn length difference will be shorter than in the case without the entanglement treatment.

The single yarn fineness of the core yarn and side yarns is expected to be strong and soft to the touch at the same time as the stiffness of the fabric, so it is better to have a large single yarn fineness for the core yarn and a small single yarn fineness for the side yarns. In particular, the single yarn fineness of the core yarn is 2.0 denier or more, and that of the side yarn is 1 denier.
．． It is preferable to set the denier to 5 denier or less, but even if there is some inversion, a soft texture can be obtained by heat treatment after false twisting or false twisting with a high number of false twists.

The heat treatment temperature after false twisting of the yarn is influenced to some extent by the false twisting set temperature, and a dual effect of temperature and tension is also observed.

If tension is applied, the effect will appear above the secondary transition temperature of 80°C, but if you take into account the false twisting temperature of 170 to 180°C or above, and also consider the stability to post-processing, the effect will be approximately 1
The temperature is preferably 50°C or higher, and the higher the temperature is, that is, the temperature of 200 to 240°C, the more stable the yarn will be.

When performing the entanglement treatment in this two-stage heat treatment section, it is necessary to adjust the tension so that a tension of about 0.5 grams to several grams is applied to the yarn in order to improve the entanglement property and the effect of the two-stage heat setting property. is preferable, but the entanglement treatment may be performed under even stronger tension.

This two-stage heat treatment reduces shear torque, improves single yarn dispersibility, and yields yarns and fabrics with a soft texture. It is possible to measure the same effect and increase in yarn length difference.

In order to do this, it is necessary to make the so-called false twist number larger than the general value (Tw), and since false twisting with a high false twist number lowers the heating tension and tends to break the yarn, It is necessary to make it higher than the appropriate stretching magnification ratio.

The following formula was used as an empirical calculation formula for these general false twist numbers and stretching ratios.

In addition, regarding the texture, appearance, and dyeability of these folded false-twisted yarns with different yarn lengths, the difference in physical properties between the core yarn and side yarns is important, and at the same time, it is important to cover the outer periphery of the core yarn. It is determined by what kind of yarn is used for the raw yarn to become the side yarn, and it is also greatly influenced by the false-twisting conditions for folding and false-twisting these yarns. The number of false twists has been described above, but the hardness, appearance, and dyeability of the product yarn are also affected by the false twisting speed. False twisting is preferably performed at t50 m/min or more, more preferably at zsom/min or more. High-speed false-twisting is recommended when low-oriented high-elongation yarns are used for the side yarns, and there is a possibility of dark coloring when low-temperature false-twisting is performed. If you do this, you will be able to obtain a desirable texture and dyeability, including rationality.

EXAMPLES AND COMPARATIVE EXAMPLES Using a polyethylene terephthalate polymer obtained by a conventional method, undrawn 75-denier spun yarns were collected at various take-up speeds, some of which are shown in Table 1.

Table 1 Two of these were combined and false-twisted under various false-twisting conditions, and the warp obtained was 800T/F72.
A woven fabric was prepared using an additional twist yarn of 1 sooT/m as the weft, and its texture and dyeability were evaluated.

Table 2 In Examples 1 and 2, fabrics with a firmer texture and a soft texture were obtained compared to the comparative examples.
Margin Table 5: Actual: Abbreviation of Example, Ratio: Abbreviation of Comparative Example In comparing Comparative Examples 1 and 3 and Example 3, Comparative Example 1 was obtained without entangling treatment and second heat setting treatment. The softness, crimp stability, and bundling properties of the yarn and fabric were also poor, whereas in Comparative Example 3, the yarn entanglement treatment was performed before false twisting.
Although the crimp stability and cohesiveness were good, the texture was hard due to the entanglement treatment applied first. On the other hand, Example 5 was subjected to the heat treatment after false twisting as in Comparative Example 3, and had a good and soft texture.

Next, Comparative Example 4 and Examples 4 to 5 are compared regarding the entanglement treatment after false twisting.

Comparative Example 4 did not undergo the second heat setting process, and Examples 4 and 5 underwent heat setting processes at 190°C and 220°C.

In both Examples 4 and 5, yarns with excellent bundling properties and crimp stability were obtained as compared to Comparative Example 4, and fabrics with a soft texture were obtained.

Margin Table 4 Example 6 is similar to Examples 4 and 5, in which entanglement treatment was performed after heat setting and false twisting, and Examples 7 and 8 were obtained by increasing the number of false twists by 200'l'/m. and one with increased false twisting speed.

Compared to Example B, the texture is softer.

Claims (1)

[Claims] 1. The following characteristics (a) to (c) and manufacturing conditions (a)
) Due to differences in physical properties or supply differences, the false twisting process is performed so that the yarn length difference under 0.2 g/dr tension is 10% or more; (b) The fineness of the single yarn of the core yarn after false twisting is 1.5 denier or more,
A spun yarn-like textured yarn characterized by satisfying the following conditions: (c) the single yarn fineness of the long side yarn is 3.0 denier or less; (c) heat treatment is performed at 150°C or higher after false twisting of the yarn. manufacturing method. 2. The manufacturing method according to claim 1, wherein entanglement treatment with a fluid is performed in the heat treatment area (between heat treatment rollers) after false twisting. 3. The manufacturing method according to claim 1, wherein an entangling treatment with a fluid is performed before false twisting. 4. The tension in the yarn before and after the fluid jet nozzle during the entanglement process is 0.
．． The manufacturing method according to claim 2, wherein the amount is 5 grams or more. 5. The manufacturing method according to claim 1, wherein the heat treatment temperature after false twisting is particularly 200 to 240°C. 6. The manufacturing method according to claim 1, wherein the single yarn fineness of the core yarn after false twisting is 2.0 denier or more, and that of the side yarns is 1.5 denier or less. 7. Stretching ratio (A) of the double yarn false twist and the number of false twists or actual number of twists satisfying (Formula B) ≧ ((DE+100)/100)×1.
05×0.625 Number of twists (B) ≧ (25500/√Dr)
+400 (However, DE represents the elongation of the core yarn before false twisting, and Dr represents the calculated fineness after stretching.) The manufacturing method according to claim 1. 8. The manufacturing method according to claim 1, wherein the doubling false twisting speed is 150 m/min or more. 9. The manufacturing method according to claim 1, wherein the false-twisting speed is particularly 250 m/min or more, and friction-type false-twisting is used.