JPS5994614A - Manufacture of polyester fiber - Google Patents

Abstract

PURPOSE:To obtain the titled fiber in high stability, suppressing the rapid increase in the tension of the running yarn by air resistance, by spinning multifilament of polyethylene terephthalate, etc., and winding the filament at a high speed under specific tension directly without using a godet roller. CONSTITUTION:A polyester composed mainly of polyethylene terephthalate is spun through the spinneret 1. The obtained multifilament is imparted with a lubricant by the oiling roller 3, passed through the traverse guide 4, and wound directly with the winder 5 without using a godet roller at a take-up speed of >=6,000m/min. In the above winding operation, the tension T1 at a position P 1.5m under the spinneret and the tension T2 just before the traverse poit Q are adjusted to satisfy the formula T2-T1<=0.3g/de and formula T2 <=10g/de.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for spinning polyester, and more particularly to a method for spinning polyester at high speed with good spinning stability.

Melt spinning of polyester is generally performed at 1000 m/min to 3
Currently, spinning is carried out at a spinning speed of about 500 m/min, but as the spinning speed is further increased, the fiber structure of the spun yarn gradually changes, resulting in changes in physical properties such as strength and elongation. are known to be close to those of practical yarns. In other words, the high-speed spinning method has the great advantage of omitting the drawing step I. However, on the other hand, the high-speed spinning method has difficult problems in producing yarn that have not been apparent in conventional spinning, including the management of spinning tension. In general, as the spinning speed increases, the tension of the running yarn increases significantly due to frictional resistance with the air, and as a result, spinning stability is impaired, such as fuzz and wraps due to single yarn breakage, which tend to occur. , the quality of the wound yarn becomes very poor, such as the natural shrinkage rate becoming high. This tendency is due to spinning M degree or 60
When spinning yarns consisting of 00 m/division, this leads to fatal consequences. That is, in this type of spinning, yarn breakage occurs frequently, making it impossible to carry out the production.

The present inventors have noted that in performing high-speed spinning at 6000 m for 7 minutes or more, it is essential to extremely suppress the rapid increase in the tension of the running yarn due to air resistance.
The present invention was arrived at as a result of extensive research.

The present invention involves spinning a polyester containing polyethylene terephthalate as a main component, and applying the spun multifilament to a 1a wine gouge at a take-up speed of 6 (,) OQm/min or more without using a Got roller. When winding the
[Spinning] A product of polyester fiber characterized in that the tension basket 1 and the tension T2 just before the traversing point in the entire 1.5 m downstream satisfy the following formulas (1) and (2)! It's in the method.

T2- T+ ku0.3 Si'/de
-= (Su'■゛2 to 1602/de...
・(2) In the method of the present invention, the tension T1 of the running yarn
The difference between and T2, that is, (T2 - T1) is 0.3 t/
By being less than or equal to cJ, e, spinning i! , 'i' becomes good, and it is further desirable that it be 0°2f/de or less. On the other hand, when (T2-T,) exceeds 0.3 y/de, the frictional resistance between the running yarn and the air is large, and fuzzing and wrapping occur frequently. The tension 1゛2 of the running yarn before traversing must be 1.0 V/de or less, and preferably 0.8 YA3e or less. And the illusion is 7, and T2 is 1. If Ofl/r3e is exceeded, the winding tension of the yarn becomes high and the winding appearance deteriorates.

There are several means to suppress the frictional resistance between the running yarn and the air, as described below. The most preferable means is to shorten the running distance of the yarn τJ.

In the case of conventional melt spinning of polyester, the traveling distance of the spun yarn before reaching the winding machine is required to be at least about 4 or more. However, as in the present invention, when the spinning speed is extremely high, the above-mentioned running distance must be set at 3.8 m or more, preferably 2.5 m or less, beyond the scope of a conventional regular job. It is necessary to design it short. In other words, in the case of conventional spinning at a relatively low speed, a mechanically or thermally stable fiber structure has not yet been developed during the spinning process, so it is necessary to design the traveling distance to be extremely short as described above. This caused variations in yarn quality of the wound yarn due to variations in cooling and tension of the yarn.

On the other hand, as in the present invention, the spinning take-off speed is 6000 m.
At ultra-high speeds of /min or more, stable fiber structure convexes with well-developed oriented crystals are almost completely developed by the time they are cooled and solidified, so longer travel distances are no longer necessary. . In fact, if the running distance is long, the frictional resistance of the air will spread over the running yarn as mentioned above, causing secondary structural changes in the cooled and solidified fibers, and as a result, the orientation distribution inside the filament will change. Changes such as enlargement that are unfavorable to the uniformity of the thread quality occur, and in severe cases, this may cause single thread breakage or thread breakage.

Another means of reducing the frictional resistance between the traveling yarn and the air is to use an air nozzle or an empty nozzle (JJ! This is a method of focusing the traveling multifilament.

In this method, the frictional resistance of the air that acts on each filament one by one is made to become a multifilament by converging the filaments together. It is something. The air nozzle used in this method may be one that focuses the filaments together and prevents frictional resistance between the air trapped inside the traveling multifilament and each filament. In particular, it does not have to be a type that causes entanglement between filaments, and it does not have to be a suction type that applies all the driving force to the downstream side.

In addition to lowering the frictional resistance with air, this method is also effective as a means of changing and adjusting the winding tension according to the brand. Furthermore, in this method, it is preferable that an oil applying device be provided between the spun 1'' gold and the air nozzle, and that the starting point of the multifilament convergence be fixed by the applying device.

This is especially important when the number of 41Es is increased, as a means of controlling the tension difference between the weights.

As yet another means of reducing the frictional resistance between the traveling yarn and the air, a vacuum spinning tube is installed between the spinning yarn and the winding machine.
There is a method of running the yarn inside the spinning cylinder. 1, that is,
According to this method, the packing density of gas (J [η is usually air) is reduced, so the frictional resistance against the running yarn is reduced. In order to achieve the object of the present invention, it is desirable that the air pressure inside the spinning cylinder is reduced by at least 40 columns of water from 1 atmosphere L1.

Next, the present invention will be explained with reference to illustrated embodiments.

In the embodiment of FIG. 1, from the spinneret 1 to the winder 5
By making the distance before winding extremely short, [
The increase in tension in the running yarn Y from a position P 1.5 m downstream of the thread 1 to a position wQ before the traversing point iff is suppressed. In order to achieve the purpose of the present invention, the distance from spinning [-1 gold 1 to winding] must be 3.5 m or less,
A suitable length is 2.5m or less.

Note that 2 is a cooling spinning tube, 3 is an oiling roller, and 4 is a traversing kite.

In the embodiment shown in FIG. 2, an air swirling nozzle 6 is provided between the spinning yarn 1 and winding with the winder 5, and by converging the traveling multifilaments, one
dil+ <The increase in spinning tension is suppressed. It's ox, in this illustration, dl, spinneret 1 and empty Ωka jj
An oil leak ζ] is provided between the nozzles 6, and a focusing device 7 is provided.
The focus point of the multifilament is controlled.

In the embodiment shown in FIG.
(Rini) increases the spinning tension by 1111. In this case, the pressure inside the vacuum spinning tube 8 is increased by the exhaust [-J8a
It is desirable that the pressure is reduced by 40σ water column or more from 1 atm.

Also, in this case, depending on the brand of spun yarn, there is a risk of insufficient cooling, so to prevent this, there is a method of cooling the spinning tube 8 using a refrigerant pipe, or a method of cooling the spinning tube 8 using a refrigerant pipe, or It is also effective to adopt a method such as cooling the spun yarn to some extent in a cooling spinning tube and then guiding it to a honey-reducing spinning tube. In addition, in Figures 2 and 3, the same 4;'M as in Figure 1 is used.
rtl: Members are indicated by the same reference numerals.The above shows several examples of the solid line M of the present invention, and the present invention is not limited to only these embodiments. It is also effective to use a combination of these methods for implementation LM.

The present invention will be explained below using a 1L example.

Example 1 Using the apparatus shown in Fig. 1, the intrinsic viscosity [η] was 0.65.
, Tie, polyethylene terephthalate containing 0.35 wt% at a melting temperature of 287 °C and a pore size of 0.25 m.
fiφ.

It is spun from a spinneret with 5 spindles and 24 holes, and after cooling and solidifying, it is wound at a speed of 7,000 m and 7 minutes.
A 75 tenier yarn was produced. The spinning device was installed on a pedestal that could be raised and lowered, and the distance from the spinning rJ gold to the winding with the winding machine was changed from 6 m to 2 m.

Length #L and position 1.5m downstream of spinneret and traverse iU
The relationship between the spinning tension 'II + 'r2 and the spinning ji (i) at the previous point is shown in Table 1.

In Tables 1161 to 1163, yarn breakage occurred because the spinning tension was too high, and satisfactory winding was not possible, but even if it was possible, fluff frequently occurred during winding for a short time. Samples Nos. 4 to 6 satisfied the conditions of the present invention, and the spinning rule r++ was good.

Example 2 A test similar to that of Example 1 was conducted at a winding speed of 6000 m/min, and the results shown in Table 2 were obtained.

Table 2 (Note) * indicates that it is outside the scope of the present invention.

A3 to A5 satisfied the conditions of the present invention and had good spinning conditions.

Example 3 Using the apparatus shown in Fig. 2, the intrinsic viscosity [η] was 0.65.
, Tie20° Polyethylene terephthalate containing 5 wt% was melted at a melting temperature of 290°C and a pore diameter of 0.20WImφ.
.

The yarn was spun from a spinneret with a land length Q of 5 mm and 24 holes, and after solidifying by cold force, it was wound at a speed of 7 ooom/min to produce a 75 denier yarn. The distance from the spinneret to the winding machine was fixed at 3.5 m, and an air swirling nozzle was installed at a position 2.5 m downstream of the spinneret.

Air pressure of air swirl nozzle and spinning tension T4. Table 3 shows the relationship between T2 and spinning tension.

Table 3 (Note) * indicates that it is outside the scope of the present invention.

A3' to A5 satisfied the conditions of the present invention and had good spinning condition.

Example 4 Using the apparatus shown in Fig. 3, the intrinsic viscosity [η] was 0.72.
, Polyethylene terephthalate containing Tie20°05wt% was melted at a humidity of 295°C with a pore size of 0 and 18 mm.
φ.

A yarn having a land length Q of 4 nm and 16 holes was spun from gold, and after being cooled and solidified, it was wound at a speed of 75 denier. Note that the distance from the spinneret to winding with the winder was 4 m, and the length of the vacuum spinning tube was 3 m. Still, the pressure inside the vacuum spinning tube was reduced to 500 cm of water column using an exhaust device.

When the spinning tension '1', T2 was measured under these manufacturing conditions, T1=0°49 t/d, T2=
0.68 Md.

T2-T, = 0.19 y/a, and the spinning condition was good.

[Brief explanation of drawings]

FIGS. 1 to 3 are overviews showing embodiments of the present invention. I1
It is a front view. L: Spinneret, 2: Cooled spinning tube, 3: Oiling roller, 4: Traverse guide, 5: Winder, P: Position 1.5 m downstream from the spinneret, Q: Position just before the traverse point, L ; Distance from the spinneret to winding, 6: Air swirl nozzle, 7: Oil applying and focusing device, 8: Vacuum spinning tube, 8a: Exhaust ITT O No. 20 No. 30 79-

Claims (1)

[Claims] (1) When spinning a polyester machine containing polyethylene terephthalate as a main component and winding the spun multifilament directly with a wine goo at a winding speed of 6000 m 7 minutes or more without using a godet roller, A method for producing polyester fiber, characterized in that the tension T1 at 1.5 m downstream of the spinneret and the tension T2 before the traverse point lK satisfy the following formula (2): Tz-T1<: 0.3 ?/ae...
41) T2 <i, Oy/de --(2
) (2) The above '11 + T2 is as follows (3),
The method for producing polyester fibers according to claim 1, which satisfies formula (4). T2 T1<, 0, 29/ae --(3)
T2 <0.8 f/de -...(4)(
5) The method for producing polyester fiber according to claim 1 or 2, wherein the distance from the spun LI gold to the point of view is 3.8 m or less. (4) @ for % correction requests where the distance from the spinneret to winding is 2.5 m or less! , The method for producing polyester fibers according to item 1 or 2. (5) The method for producing polyester fibers according to claims 1 to 4, wherein the multifilaments are bundled using an air turbulence nozzle or an air swirling nozzle during the process from the spinneret to winding. (6) The method for producing polynisder fibers according to claim 5, wherein a bending agent is applied to the multifilament between the spinneret and the air turbulence nozzle or the air swirl nozzle.゛(7) Claims 1 to 6 in which the multifilament is made to run in a reduced-pressure spinning cylinder whose pressure is reduced by at least 40 columns of water from 1 atm between the spinneret and winding. The method for manufacturing the polyester fiber described.