JP2609009B2 - Method for producing polyester ultrafine fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an improved polyester ultrafine fiber, and more particularly to a method for producing a polyester ultrafine fiber which has been subjected to a special entanglement treatment, has less fluff, and has excellent post-processability.

[0002]

2. Description of the Related Art As a method for producing ultrafine fibers, there are a dissolving method, a splitting method and a direct spinning method.
It is excellent as an industrially inexpensive method for producing yarns of denier or less. Among them, the direct spinning and drawing method is effective for filament, and there is a demand for a brushed fabric or a high-grade woven or knitted fabric material utilizing the extra fine characteristics. There is a sharp increase, and there is a strong demand for ultra-fine fibers having high productivity and excellent post-processability.

As a direct spinning method of ultrafine fibers, a method of spinning at a high speed of 3000 to 5000 m / min under a specific draft is disclosed in JP-B-58-37408 and JP-A-61-18.
Although it is described in, for example, JP-A No. 6515, there is no description on post-processing passability as it describes how to make it ultrafine.

On the other hand, there has been proposed a melt spinning method in which a yarn is entangled with an interlaced nozzle in a spinning step and then wound up.
No. 17 describes a method of entanglement treatment with a plurality of interlace nozzles and winding at a spinning speed of 5,000 m / min or more, but there is no description about a polyester ultrafine yarn having a single yarn of 0.5 de or less. .

[0005] In recent years, in order to increase productivity in response to an increase in demand for ultra-fine yarn, speeding up of spinning and warping and weaving have been performed, and post-processing such as high-speed unwinding and high-speed flight has been performed. A demand for a yarn having excellent properties has been demanded also for an ultrafine fiber.

With respect to polyester ultrafine fibers having a single yarn fineness of 0.5 denier or less and a single yarn number of 50 or more, simply increasing the number of interlace entanglements as in the related art will result in a thin single yarn. Fuzz generation is promoted, and satisfactory high-speed spinnability and post-processability cannot be obtained.

For example, as shown in FIG.
Oil supply device 3 and interface nozzle 4
The device which obtains microfibers in the device equipped with
The spinning tension is high because the yarn is pulled at 00m / min.
It is difficult to impart confounding of 0 / m or more, and even if it can be performed, the fluff will increase.

FIG. 4 shows the arrangement of the oil applying device 3 and the interface nozzle 4 in front of the take-up roller 5, and the interface between the take-up roller 6 and the take-up device 9 at the rear. The number of entanglements entering at the front interface is regulated by the spinning tension, and the rear interface between the rear take-up roller 6 and the winding device 9 is provided. -The number of confounds at the race is regulated by the winding tension. Therefore, to increase the number of entanglements, it is necessary to lower the spinning tension or the winding tension.
It is difficult to insert more than 10 m / m.

The inventors of the present invention have excellent high-speed spinnability and warp,
As a result of intensive studies on polyester ultrafine fibers having excellent post-processing properties such as weaving properties, a total of 15 fibers were obtained by individually performing entanglement treatment using different interface nozzles at each place where tension control was possible. It has been found that a fiber having an entanglement number of / m or more achieves the object, and has reached the present invention.

[0010]

An object of the present invention is to provide a method for producing a polyester fine fiber which has a special yarn entanglement and is less fuzzy and has excellent post-processability.

[0011]

According to the present invention, a polyester is melted and discharged through a spinning hole to obtain a polyester ultrafine fiber having a single yarn fineness of 0.5 denier or less and a single yarn number of 50 or more. -Using a lubricant applying device and an interface nozzle having three or more holes before the roller, performing the first-stage entanglement treatment, and taking over at 3000 m / min. The stretching is performed between the stretching rollers , and one hole or two holes are formed between the stretching roller and the substantially unheated intermediate roller.
A method for producing ultrafine polyester fibers, wherein a second stage of entanglement treatment is carried out using an interlace nozzle having holes and the total number of entanglements is 20 pieces / m or more.

Hereinafter, the present invention will be described in detail. The polyester fiber of the present invention is intended for a polyester filament whose repeating unit is composed of ethylene terephthalate.
However, the terephthalic acid component and / or ethylene glyco-
A small amount (usually 20 mol% or less based on the terephthalic acid component) of the third component other than the polyester component may be copolymerized. Polyester may be used.

If necessary, additives such as an antistatic agent, a matting agent, an ultraviolet absorber, and a dye improver may be mixed into the polyester.

The polyester ultrafine fibers of the present invention have a single yarn fineness of 0.5 denier or less and a single yarn number of 50 or more. The fineness of single yarn can be as thin as possible, but it is 0.05 denier or more at present. The number of single yarns is determined by the required total denier, and is 50
The above is normal. When the single yarn fineness is less than 0.05 denier, fluff is generated so that it is difficult to handle as filament. If the single-fiber fineness is larger than 0.5 denier, the feeling as an ultrafine fiber is unfavorable.

When the number of single yarns is smaller than 50, the total denier becomes smaller than 25 denier, and the passability in post-processing becomes poor. The upper limit of the number of single yarns is determined by the required total denier.
500 or less.

[0016] The polyester ultrafine fiber of the present invention
The number of laser confounds is 20 or more / m. Those having less than 20 pieces / m are not preferred because they tend to cause thread breakage and fluff during high-speed aging and high-speed weaving. The higher the number of confounds, the better, but from the viewpoint of economy and operability, 50 pieces / m
A degree is enough.

The polyester fiber of the present invention as described above can be obtained by the following production method. That is, the aforementioned polyester is melted and discharged from the spinneret. After passing through a heating heater provided just below the base and cooling and solidifying, the oil was applied using an oil agent application device, and then the pre-
Using a laser nozzle, the first stage of entanglement treatment is performed and 3000
Withdraw at m / min or more. Then, the film is stretched between the take-up roller and the stretching roller without being wound once, and is heat-treated with the stretching roller, and further between the stretching roller and the substantially unheated intermediate roller. After the second stage of confounding using the rear interface nozzle, winding is performed.

FIG. 1 shows an example of such a process, and shows a schematic diagram of a process suitable for carrying out the present invention.
In the figure, a yarn y melt-discharged through a spin block 1 is cooled and solidified through a heating heater zone 2, then oiled by an oil application device 3, and then entangled by an interlacing nozzle 4. After that, it reaches the pickup roller 5.

The yarn y is drawn between a take-up roller 5 and a drawing roller 6, and is passed through a post-interlacing nozzle 7 and a substantially unheated intermediate roller 8 to a winding machine. 9 is wound up.

The degree of polymerization of the polyester should be appropriately selected according to the type of the polyester and the use of the product ultrafine fibers, but a limiting viscosity [η] of 0.55 to 0.65 is suitable.

The spinneret 1a has a spinning hole diameter of 0.1 to 0.2 mm.
It is preferred to use The spinning temperature is 290
To 305 ° C., and the yarn y discharged from the spinneret 1a is preferably heated by a heating heater provided immediately below the spinneret. This heating heater is preferably provided to control the spinning tension of the yarn discharged from the die 1a. If there is no heating heater, the spinning tension is controlled by the spin block temperature and the cooling rate. Inevitably, it becomes difficult to obtain a desired fiber. It is preferable that the temperature of the atmosphere 10 mm below the base is maintained in the range of 240 to 300 ° C. by a heating heater.

The yarn y which has passed through the heating heater zone 2 is cooled and solidified by blowing cooling air at room temperature from the lateral direction, and a predetermined oil agent is applied by the oil applying device 3. Thereafter, the first interlacing process is performed by the first interface nozzle 4.
The front interface nozzle 4 is a nozzle having three or more holes.
Here, the three-hole nozzle is a nozzle in which three fluid ejection holes for ejecting a pressurized fluid are present on the nozzle cross section, and it is desirable that the positions thereof be arranged rotationally symmetrically. Specifically, an interface nozzle as shown in FIG. 2A is preferably used. In FIG. 2A, reference numeral 41 denotes a yarn guide, and reference numeral 42 denotes a fluid injection hole.

Normally, the greater the number of holes, the smaller the number of confounds at the same compressed air flow rate, and the weaker the confounding. In the present invention, a nozzle having three or more holes is used as the interface nozzle 4, and relatively weak confounding is given by the confounding number, preferably 10 / m or more. When a one-hole nozzle or a two-hole nozzle is used, relatively strong entanglement occurs, which is not preferable because stain defects are likely to occur in the subsequent stretching step. On the other hand, when the number of entanglements is less than 10 pcs / m, yarn swaying on the roller or breakage of fluff single yarn is liable to occur in a subsequent step, and the high-speed spinnability is reduced.

When the take-off speed is lower than 3000 m / min, it is necessary to set a higher magnification in the stretching step in order to obtain a desired yarn quality. When the number of confounds is set to less than 10 /, fluff is likely to occur.

The yarn y picked up by the pick-up roller 5 is drawn with the drawing roller 6 without being wound once. The draw ratio is appropriately selected in order to obtain a desired yarn quality, but is usually 1.01 times or more and 1.5 times or less. At this time, the take-up roller 5 may be a heating roller for preheating. Heat treatment can be performed continuously from the stretching step to reduce the boiling water shrinkage to 10% or less. This can be dealt with by making the stretching roller 6 a heating roller.

Subsequent to the stretching step, a second-stage entanglement process is performed between the stretching roller 6 and the intermediate roller 8 by using the rear interface nozzle 7. The nozzle used for the rear interface nozzle 7 is a two-hole nozzle or a one-hole nozzle because it has a strong purpose of performing high entanglement. Specifically, a nozzle as shown in FIG. 2B is preferably used. 71 is a thread guide, and 72 is a fluid ejection hole.

It is a point of the present invention that a weak confounding process is performed at the first interface, and then a strong confounding process is performed at the rear interface.

The two-stage entanglement treatment is performed by using a stretching roller 6 and an intermediate roller.
And the pressure and air pressure of the nozzle.

Overfeed rate (hereinafter abbreviated as OF rate)
Is defined as follows:

OF ratio = ｛(stretch roller speed− (intermediate roller−
(Speed) 速度 / stretching roller speed The OF rate is preferably 0.5% or more and 3% or less. If it is less than 0.5%, the pneumatic pressure increases to obtain a desired number of confounds, and fluff is likely to occur. On the other hand, if the OF rate is higher than 3%, the yarn is wound around the roller, so that the high-speed spinnability is reduced.

Regarding the intermediate roller 8, the term “substantially non-heating” generally means room temperature and does not cause thermal shrinkage of the yarn, and is preferably a mirror-finished roller. This is to maintain the tension balance between the area from the stretching roller to the intermediate roller and the area from the intermediate roller to the winding machine. When the surface of the intermediate roller is satin, the yarn warp increases on the roller and the drawing roller
The difference in tension between the roller and the intermediate roller propagates to the winder, and the yarn easily winds around the intermediate roller.

[0032]

The present invention will be described more specifically below with reference to examples.

The number of confounds was determined by ROTHSHILD E
Using NTANGLEMENT TESTER R2040, winding was carried out at a constant running tension of 10 g at a rate of 30 m / min, a pin tension of 15 to 18 g was applied to the yarn, and the total length was obtained from 20 total yarn lengths.

The weaving property was judged from the number of stops when weaving was performed at a speed of 600 rpm using Nissan LW-52 type WJL.

[0035]

Examples 1 to 3 and Comparative Examples 1 to 6 Polyethylene terephthalate having an intrinsic viscosity [η] of 0.64 measured with an O-chlorophenol solution at 35 ° C. (a titanium oxide content of 0.3)
%) From a 72-hole spinneret at a temperature of 298 ° C., and after passing through a fixed heater zone under the spinneret, the discharged yarn is blown across the yarn in a spinning cylinder. It was cooled and solidified by the cooling air that came out. After this, apply the oil agent,
90 ° C. after confounding by the interlace nozzle
After winding 6 times around a take-up roller heated to 130 ° C.
Was wound four times around a heated drawing roller, and then subjected to a confounding process using a post-interlace nozzle, and a 32 denier / 72 filament yarn was wound through an intermediate roller.

At this time, spinning conditions and interface conditions were changed. Table 1 shows the conditions, the spinning condition, the number of entanglements, the appearance fluff, and the post-processability of the obtained multifilament.

[0037]

Comparative Example 7 Winding was carried out in the same manner as in Example 1 except for the spinning machine, spinning conditions and interface conditions shown in Table 1.
Table 1 shows the results.

[0038]

[Table 1]

The criteria for the results in Table 1 are as follows.

[0040]

[Table 2] Spinning condition A: excellent, O: good,
△: Slightly poor, ×: Poor appearance Fluff ◎: None, O: Almost none, △:
There is a little, ×: Multiple occurrences Post-processing passability: Judgment by the number of times the loom stops Unit: times / day ◎: ≦ 5, O: 6 to 10, △: 10 to 20,
×: ≧ 20 spots ◎: none, O: almost none, △:
There is a little, ×: stand out

[0041]

As described above, according to the present invention, since the polyester ultrafine fiber is subjected to a special yarn entanglement treatment, it has a remarkable effect of being excellent in high-speed spinning properties and excellent post-processability.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a manufacturing process suitable for carrying out the present invention.

FIG. 2A is a sectional view of a front interface nozzle suitable for carrying out the present invention. (B) It is sectional drawing of the rear interface nozzle suitable for implementing this invention.

FIG. 3 is a schematic view of a manufacturing process showing a conventional example.

FIG. 4 is a schematic view of a manufacturing process showing a conventional example.

[Description of Signs] 4 Front interface nozzle 5 Take-in roller 6 Extension roller 7 Rear interface nozzle 8 Intermediate roller 9 Winding machine 42 Fluid injection hole 72 Fluid injection hole

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location D02J 1/00 D02J 1/00 L

Claims (1)

(57) [Claims] 1. A polyester is melt-discharged through a spinning hole and has a single yarn fineness of 0.5 denier or less and a single yarn count of 50 or less.
When obtaining the above polyester ultrafine fibers, an oiling device and an interface having three or more holes before the take-off roller.
Using a nozzle, the first stage of confounding treatment is performed, and 3000 m /
min or more, the film is stretched between the take-up roller and the stretching roller without being wound once, and a one-hole or two-hole interface is formed between the stretching roller and the substantially unheated intermediate roller. -A second stage of entanglement treatment using a nozzle, and winding with a total number of entanglements of 20 / m or more, and winding.