JPS58208427A - Production of 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 a processed polyester yarn with good setting properties.

Conventionally, when polyester processed yarns have been used in flat knit sweaters, there has been a problem with setting properties. In other words, flat-knit sweaters are usually knitted and linked into a product shape and then body-set using steam, but polyester cannot be set at temperatures as low as normal pressure steam, and therefore requires high-pressure setting equipment. However, this hindered the entry of processed polyester yarn into the sweater field. In addition, in order to solve this problem, polyester processed yarn can also be set at low temperatures by performing wooly processing at as low a temperature as possible and not subjecting it to strong heat history, preserving the properties of raw silk as much as possible and allowing it to be set even at low temperatures. There is a way to make it more effective, but since the Nako yarn itself is not woolly processed at high temperatures, it has very weak crimp and the product has no texture. .

The present invention is free from such limitations and provides a method for producing textured yarn in which strong crimping can be applied freely while the product can be sufficiently set using atmospheric pressure steam or the like.

That is, the present invention uses a fiber-forming polymer having polyethylene terephthalate as the main repeating unit at
High-speed spinning is carried out at a speed of 1 sjn or more, and the spinning is carried out at a temperature of 0.1 sjn or higher at a temperature higher than the crystallization temperature. Crystallinity degree 2 after heat treatment for 01-1.0 seconds
This is a process for producing a textured yarn, which is characterized in that after the yarn is made to have a thickness of 0 or more, it is further stretched at a temperature below the secondary dislocation point, and then false-twisted.

To further explain the present invention in detail, the leaf material used in the present invention is a fiber-forming polymer (sweet polyester) whose main repeating unit is polyethylene terephthalate.
is suitable. This is because, as mentioned above, when polyester is normally made into thread, it has good setting properties at high temperatures, but it hardly sets at low temperatures, so the improvement effect may be large.

Next (C1) The above polymer is spun at high speed in order to facilitate crystallization in the subsequent heat treatment process.In other words, if the spinning speed is low, the orientation will be low during heat treatment at a high temperature, so the fibers will be separated from each other or the fibers will be A phenomenon of fusion or softening occurs between the material and the heat treatment equipment.

Therefore, the higher the spinning speed, the better, at least 2500
A high spinning speed of y+/Mm is required. Moreover, this...
High-speed spinning increases the number of nuclei that form the base of crystals, which makes it easier to grow crystals during subsequent heating, and from this point of view, a value of 32 QOm/M or more is desirable.

Next, the spun yarn is heat treated to crystallize it.

This is because the molecular structure is pre-crystallized so that the molecular structure does not align excessively even if strong heat and tension are applied during the subsequent drawing and false-twisting process. If the crystallinity is lower than 5%, the low temperature setting properties will be impaired when strong heat setting is applied during false twisting. When the crystallinity is 28 inches or more, any kind of false twisting can be applied without any problem. In addition, to perform such crystallization, K must be spun at high speed and the spun yarn formed into a bale of hoof crystals h'' must be heated above the crystallization temperature.The crystallization temperature depends on the heating time at that time. However, it is desirable to set the temperature to, for example, 50°C or more, preferably 70°C or more to the secondary transition temperature of the fiber.

In particular, if the temperature exceeds the secondary dislocation temperature plus 85°C, no matter what kind of processing is applied, there will be problems. In addition, the heat treatment time requires the time required for fiber car crystallization, and is at least 0.0
1 second or more is necessary; however, if it is too long, the fibers will become brittle and spots will occur during subsequent processing, so the longest time is 1.0 seconds.
The limit is seconds, and preferably 0.5 seconds or less.

The thus crystallized yarn is further drawn at a temperature below the secondary dislocation point. Here, stretching false twisting may be performed directly in the heat treatment system in the false twisting process, but if the stretching is performed in advance at a temperature below the secondary dislocation point as in the present invention, the heat treatment in the crystallization treatment is It has the advantage of being lightweight.

In other words, by strongly performing this heat treatment crystallization,
I wonder if this means that even if the yarn is false-twisted at high temperatures, the yarn's easy-setting properties are maintained.In order to do so, a strong heat treatment that does not easily disappear after false twisting of 710 degrees is required, especially during drawing. This point is important when false twisting is performed at high temperatures. However, as in the present invention, if the temperature and time of the crystallization heat treatment can be reduced to some extent by first stretching at a temperature below the secondary dislocation point and then performing the false twisting process, it is possible to reduce the crystallization heat treatment temperature or time. This method is effective. In addition, the temperature at that time is preferably as low as possible in order not to reduce the effect of the preheat treatment, and at most the secondary dislocation point temperature of the yarn,
In particular, it is preferable to cold stretch at room temperature, where the temperature of the secondary dislocation point is -40°C or lower.In addition, the stretching ratio at that time is such that all necessary stretching is performed at this stage, and the next false twisting process is carried out to a fixed length. Alternatively, it is desirable to carry out the stretching by relaxation, but in some cases, it is better to divide this stretching evenly between the two parties.However, even in that case, it is desirable to take care of at least half of the stretching.

Finally, the cold-stretched filament is subjected to a temporary warping process, which is preferably carried out in a long or relaxed state as described above.
If the strong crystallization treatment causes the formation of 26 fibers and prevents the fabric from forming, it is difficult to perform false twisting. It is preferable to carry out the process by pre-stretching.Furthermore, even if the number of false twists and heat treatment are repeated in the same way as normal false-twisting, the yarn has easy-setting properties, which is a major advantage of the method of the present invention.・'# length.In other words, according to the present invention, there is no need to particularly lower the heat treatment temperature to an extremely low temperature, and the knitted fabric can be false-twisted even if the yarn is processed at normal false-twisting temperatures. It is truly amazing that just blowing steam (less than 100 degrees Celsius) at a temperature much lower than the actual temperature is enough to set the yarn.By taking advantage of these advantages, it is possible to without compromising its excellent crimp bulkiness.
It becomes possible to finish it into a flat knit sweater like other fibers (acrylic, wool, etc.).

In the present invention, any means for imparting false twisting may be used, such as a spindle type or a twister type. Further, the finished processed yarn may be used after being subjected to so-called two-heater processing, so that the setting properties are not lost. This also applies after dyeing. The material used in the present invention is polyester as described above, but it may also contain a so-called third component in the form of copolymerization or blending.For example, if a cationic dyeable component is added, the product can be improved. Since it can be dyed with cationic dyes, the clarity improves, making it suitable for -4 flat knit sweaters.Furthermore, the process of heat-treating and crystallizing the high-speed spun yarn may be performed in a separate process. However, it is generally efficient to attach a spinning hot roller to the spinning machine and carry out continuous heat treatment.

Alternatively, it is also possible to provide a heat-treated strawberry that is stretched below the secondary dislocation point and to follow this continuously. In this case, whether the heat treatment is relaxed, constant length, or under tension, the necessary crystallization can be obtained and fc tt is good, but in general, the setting property of the product is better when heat treated in the constant length or relaxed state. In good condition.

However, in this heat treatment, active stretching should be avoided; even if the yarn is loosened, the yarn will be disordered; (this will result in poor handling later on, so it is better to keep the relaxation to 8 degrees or less. Also, 2?7.
The step of stretching below the transposition temperature is continuous with the above-mentioned black heat treatment step 1. It can also be used in conjunction with false twisting.
You can also use it.

As described above, according to the present invention, not only can it be possible to obtain a processed yarn with excellent winding properties by increasing the setting temperature during false twisting, but also the processed yarn can also be used in subsequent steam setting. It has the unique effect of being easy to set, which is unprecedented.

Next, an example of implementing the present invention will be shown.

Example 1 A polyethylene terephthalate homopolymer with an intrinsic viscosity of 1i0.64 was spun at a spinning speed of 3300 y (/#Il++) to obtain a raw yarn of 31 S De/72 Fil. After heating the yarn for 0.1 seconds while relaxing it in a non-contact state to reach a crystallinity of 364K, the yarn was continuously stretched to 1.3 times while being cooled with a cold roller and stretched to 250 De/y 2 Ftl. Got the thread.

Next, this was made into a fixed length using a spindle false twister with a number of false twists of 17.
00 t/@, processing was carried out at a set temperature of 190°C, and further set at 210°C while relaxing 5 inches using a secondary heater.

This yarn is skein-dyed with disperse dye.
It was knitted using a G IJ knitting machine and its setability was evaluated.

The evaluation of setability is 9 when the knitted fabric is stretched by 10% with a metal frame.
After spraying 0℃ steam for 10 seconds, remove the metal frame and measure the return rate.If the metal returns to the first metal, the set rate = 0%.
The case where no return occurred was defined as a set rate of 10%. As a result, this sample had a good rating of 94% for Cera M4, which was at a level that would be sufficient to set the body as a sweater.

Example 2 38001n of polyethylene terephthalate copolymerized with 2.6 mol of 5-sodium sulfophthalic acid
/van speed at 190℃90 at the same time while spinning at high speed.
The fibers were heat-treated for 0.03 seconds at a constant length in a Hollerer to obtain a 125De/36Fil yarn with a crystallinity of 28%. Next is this? The material was internally stretched to 1.2 times in an a-lar at room temperature, and then continuously fed to a 7-reaction machine at a stretching ratio of 1.05 times.

Perform false twisting at a set temperature of 200℃, 100De/
36 File e) Obtain processed yarn. Next, tie this thread to 3
The book was assembled into a 12Gi Lanoliff and dyed with a cationic dye, and its setability was evaluated; the set rate was 91.
It has a good texture, and the texture is similar to that of polyester jersey.

The tension was as expected.

As described above, according to the uninvented method, it is possible to set the product using a simple method such as normal pressure steam while maintaining the high crimpability of the processed polyester yarn.

Patent applicant Teijin Ltd.

Claims (1)

[Claims] (1) Fiber-forming polymer containing polyethylene terephthalate as the main repeating unit at 2500 m/jirn
High-speed spinning is carried out at a speed higher than 0.000. A method for producing textured yarn, which comprises heat-treating for 1 to 1.0 seconds to obtain a crystallinity of 20% or higher, further stretching at a temperature below the secondary dislocation point, and then false-twisting.