JP2003213517A - Method and apparatus for producing synthetic fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for producing a synthetic fiber, enabling speeding-up of spinning velocity while suppressing orientation unevenness and fluctuation of filaments. <P>SOLUTION: This method for producing a synthetic fiber comprises carrying out melt spinning of a plurality of filaments F from a spinneret 2 having a plurality of discharge holes 3, blowing cooling air to these spun filaments F in obliquely lower direction to filament traveling direction to cool these spun filaments F and applying stream parallel to the traveling direction to these spun filaments to pull these filaments. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for producing synthetic fibers, and more particularly, to improve the cooling process unevenness of the spun filament by suppressing the yarn swaying under the spinneret in the melt spinning, and to perform the cooling process. The present invention relates to a synthetic fiber manufacturing method and apparatus capable of obtaining a high-quality yarn even if the spinning speed is increased by relaxing the subsequent spinning tension and suppressing the progress of orientation.

[0002]

2. Description of the Related Art When synthetic fibers such as polyester are produced by melt spinning, productivity can be improved and cost can be reduced by increasing spinning speed.

However, when the spinning speed is increased, the spinning filaments in the spun filament during melt spinning increase as the spinning speed increases, and due to the increase in the spinning thread, the yarn filament unevenness and single yarn breakage increase, and Quality is reduced. Furthermore, since the tension acting on the spun filament increases and the orientation advances, the elongation of the yarn decreases, making it impossible to obtain a yarn having the desired physical properties. If there are spots on the thread, problems such as fluff and thread breakage are likely to occur, making stable processing impossible.

As described above, as long as the conventional technique is used, there is a certain limit for improving the productivity by increasing the spinning speed while maintaining the physical properties and quality of the yarn at a certain level.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to improve the cooling treatment unevenness of the spun filament by suppressing the fluctuation of the yarn under the spinneret in the melt spinning, and to relax the spinning tension after the cooling treatment to achieve the orientation. It is an object of the present invention to provide a method and an apparatus for producing synthetic fibers, which enables high-quality semi-drawn yarn (POY) to be produced at a high speed by suppressing the progress of the above.

[0006]

In the method for producing synthetic fibers of the present invention to achieve the above object, a plurality of filaments are melt-spun from a spinneret having a plurality of discharge holes, and cooling air is blown to these spun filaments. Is sprayed obliquely downward and cooled, and then the spun filament is provided with an air flow parallel to the running direction of the spun filament.

Further, in the synthetic fiber manufacturing apparatus of the present invention, the cooling air is blown obliquely downwardly below the spinning portion provided with a spinneret having a plurality of discharge holes to the filament to be melt-spun from the spinning portion. A portion is provided, and further, below the cooling portion, a parallel airflow imparting portion that applies an airflow parallel to the filament traveling direction to the filament is provided.

Since the cooling air is blown to the filaments melt-spun from the spinneret in a diagonally downward direction with respect to the yarn traveling direction, the velocity component of the velocity energy of the cooling air in the traveling direction of the spun filament is large. Become.
As a result, the tension of the spun filament is increased, and the spinning state is stabilized even if the spinning speed is increased. Further, by providing an air flow parallel to the spun filament downstream and pulling the spun filament, the tension of the spun filament after the cooling treatment is relaxed and the progress of orientation is suppressed, so that a high elongation yarn property is obtained. In addition, it is possible to obtain a high-quality semi-drawn yarn in which problems such as fluff and yarn breakage in higher-order processing such as drawn false twist processing are reduced.

Further, since the cooling air is directed obliquely downward, it is possible to reduce the effect of lowering the temperature of the surface of the die, and further to reduce the occurrence of yarn unevenness and single yarn breakage.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION
In the melt-spinning method of a thermoplastic polymer, the filaments melt-spun from a spinneret are cooled by blowing cooling air diagonally downward with respect to the yarn traveling direction.

By blowing the cooling air obliquely downward to the filaments to be melt-spun, it is possible to increase the velocity component of the velocity energy of the cooling air in the traveling direction of the spun filaments and increase the tension of the spun filaments. it can. Further, the limit speed of the spinning speed at which the yarn does not shake can be increased by the amount of the increased tension.

Further, by making the cooling air obliquely downward with respect to the yarn traveling direction, the influence of cooling the surface of the spinneret by the cooling air is reduced, and the occurrence of yarn wobbling due to the lowering of the surface temperature of the spinneret is also reduced. Thus, the spinning state can be stabilized.

The melt spinneret used in the present invention includes:
It is preferable that a plurality of discharge holes are arranged in a row. The number of ejection holes arranged is preferably one row, but two or more rows may be arranged in parallel. The array is preferably linear. When arranging in two or more rows, it is preferable that the ejection holes in each row do not overlap each other in the direction orthogonal to the arrangement direction.

Since the spun filaments are arranged in the same row from the plurality of discharge holes arranged in a row in this manner,
Cooling air is blown diagonally downward with respect to the yarn traveling direction from one of the sides in the arrangement direction of the plurality of spun filaments. By blowing such cooling air, the cooling air is evenly applied to each spun filament, and the quality of all of the plurality of filaments can be made uniform.

The blowing angle of the cooling air with respect to the spun filament is not particularly limited, but is preferably in the range of 15 to 70 degrees, more preferably 30 to 50 degrees.
If the spray angle is less than 15 degrees, the tension cannot be increased until the yarn fluctuation of the spun filament is suppressed,
On the other hand, if the angle is larger than 70 degrees, the side surface of the spun filament on which the cooling air directly acts and the side surface on the opposite side have different magnitudes of the air force of the cooling air with respect to the traveling direction, resulting in yarn unevenness. .

Generally, the blowing angle of the cooling air is in the range of 15 to 70 degrees, so that a semi-drawn yarn having almost no defects in quality can be obtained, and by setting it in the range of 30 to 50 degrees, a good semi-drawn yarn is obtained. To be Furthermore, it is preferable to provide a straightening vane at the blowout port in order to adjust the blowing angle in accordance with the spinning temperature, the fineness of the spun yarn, the number of spinning yarns, and the like, and make the angle variable by adjusting the inclination angle of the straightening vane. By making the angle of the cooling air in the spraying direction adjustable in this way, the spraying angle can be optimally set according to the spinning conditions.

The cooling air may be discharged as it is after it is blown onto the spun filament, but it is preferable to forcibly suck it by providing a suction port on the opposite side. The cooling air after cooling the spun filament contains a large amount of monomers and oligomers evaporated from the spun filament.

If these evaporates accompany the spun filament along the downstream yarn path and adhere to the periphery, it may impede the running of the spun filament or may adhere to the spun filament again to deteriorate the yarn quality. To do. However, as described above, these obstacles can be eliminated by providing the suction port opposite to the cooling air outlet and forcibly sucking and removing.

A parallel airflow providing unit is connected to the lower portion of the cooling unit. The parallel airflow imparting section is configured to apply an airflow of compressed air or the like in parallel to the spinning filaments moving in the yarn path, and by applying the parallel airflow, the tension of the spinning filaments after cooling treatment is relaxed, It acts to suppress the progress.
Generally, when the spinning speed is increased, the orientation of the spun filament progresses. For example, in the case of polyester semi-drawn yarn (POY) used for draw false twisting, if the orientation is too advanced, single yarn breakage occurs frequently. This is because it deteriorates the operability and the yarn quality and is effective in suppressing the orientation.

The polyester semi-drawn yarn produced by the prior art is said to have a suitable orientation obtained from a spinning speed of 2000 to 4000 m / min. The semi-drawn yarn obtained from the spinning speed higher than 4000 m / min has a higher orientation because the orientation is too advanced, and fluff and yarn breakage are likely to occur during draw false twisting, which deteriorates yarn quality and operability. I was told that I couldn't.

However, as described above, the parallel air flow imparting part is connected to the lower part of the cooling part to give an air flow parallel to the running direction to the spun filament to relax the spinning tension after the cooling treatment and suppress the progress of orientation. As a result, high-yield yarn properties are obtained, and high-quality semi-drawn yarns with less fluff and yarn breakage even in higher-order processing such as draw false twist processing are obtained, increasing spinning speed and productivity. Can be improved.

In the melt-spinning step, an oil agent is generally added before winding the spun filament into a package. The oil agent added in the melt spinning process improves the handling property of the filament yarn, and improves the process passability when used in the higher-order draw false twisting process or the weaving / knitting process.

As a method of applying the oil agent to the spun filaments in the melt spinning step of the present invention, it is preferable to carry out the spun filaments in a state in which they are arranged in rows. In this way, by applying the oil agent in a state in which a plurality of spun filaments are arranged in rows, the oil agent can be evenly applied to each filament, and the yarn quality can be further improved.

The thermoplastic polymer applicable to the present invention is not particularly limited as long as it can be spun into yarn. In the explanation of the above-mentioned means for imparting parallel airflow, the case of polyester semi-stretched yarn was illustrated, but other than this, polyamide and copolymers thereof can be preferably used. The spinning speed applied to the present invention is not particularly limited, but can be, for example, 4000 m / min or more, and further 5000 m / min or more by using the manufacturing apparatus of FIG. 1 described below.

FIG. 1 shows an outline of an apparatus for producing synthetic fibers according to the present invention, and particularly shows a case where a polyester semi-drawn yarn is produced in a melt spinning process.

1 is a spin block of a melt spinning machine,
A base 2 is attached to the bottom of the spin block 1. A plurality of discharge holes 3 are formed in the base 2 so as to be linearly arranged in a direction orthogonal to the paper surface (see FIG. 2).
A cooling unit 4 is provided below the base 2, and a parallel airflow providing unit 5 is further connected. Further, below the parallel airflow providing unit 5, an oil agent applying unit 6, a focusing guide 7, an entanglement nozzle 8, and a first take-up roller 9 are sequentially provided. Further, a second take-up roller 10 paired with the first take-up roller 9 is provided obliquely above and a winder 11 is provided below it.

The thermoplastic polymer melted by the melt spinning machine is melt-spun into a plurality of filaments F arranged in rows from the discharge holes 3 of the die 2. The plurality of filaments F melt-spun from the spinneret 2 are cooled by cooling air in the lower cooling unit 4, and then flow down while being imparted with parallel airflow by the parallel airflow imparting unit 5.

Filament F exiting from the parallel airflow imparting section 5
While being drawn by the first take-up roller 9 and the second take-up roller 10 at a constant speed, the oil agent is applied by the oil agent applying means 6 in the meantime, and the yarn is focused on one yarn by the focusing guide 7 and then the entanglement nozzle. At 8, the turbulence of the compressed air is applied and the filaments are entangled with each other. Furthermore, the filaments F that have come out of the second take-up roller 10 and are in a bundled state are
The bobbin 13 on the first spindle 12 is wound up as a package P.

In the above structure, the cooling unit 4 has a plurality of filaments F arranged in a line in a direction orthogonal to the plane of FIG. 1 with a cooling air outlet 41 on one side in the arrangement direction and on the other side. A cooling air suction port 42 is provided. A large number of straightening vanes 41a are provided at the cooling air outlet 41 so as to incline obliquely downward, and the cooling air is blown to the spun filament F obliquely downward from one side in the arrangement direction.
The connecting pipe 43 on the upstream side of the cooling air outlet 41 is connected to an air supply blower (not shown).

The cooling air suction port 42 is similarly provided with a large number of slanted rectifying plates 42a so that the cooling air blown out from the cooling air outlet 41 is forcibly sucked. The downstream side of the cooling air suction port 42 is the exhaust port 4
It is connected to the exhaust blower (not shown) via the No. 4.

In the cooling section 4, the cooling air is blown obliquely downward from the cooling air outlet 41 from one side in the arrangement direction to the spun filaments F flowing down in the row arrangement as described above. As the cooling air is blown obliquely in this way, the component of the velocity energy of the cooling air given to the traveling direction of the spun filament F becomes larger than that when it is blown at a right angle, and the spinning up to the die 2 is performed. Increase the tension of filament F.

Such an increase in the tension of the spun filament F makes it possible to increase the upper limit of the spinning speed at which spinning is possible without causing yarn wobbling, and the productivity can be improved by increasing the spinning speed. . Further, since cooling air is blown from a single side in the arrangement direction to the plurality of spun filaments F arranged in a row, the cooling air can be uniformly given to each spun filament F, and the spun filaments are Make the entire F uniform quality.

In the parallel airflow imparting section 5, the cross section of the yarn path 51 is formed in a rectangular shape so as to surround the spun filaments F arranged in rows (see FIG. 4). And thread trail 5
Ejector nozzles 52, 52 are provided on both sides of the upper part of the unit 1 so as to be directed obliquely downward to inject pressurized air.

The pressurized air jetted from the ejector nozzles 52, 52 is supplied obliquely downward to both sides of the spun filaments F arranged in rows, and in the yarn path 51, in the same direction as the spun filaments F. Since they flow in parallel, the tension of the spun filament F is relaxed and the progress of orientation is suppressed.

The parallel air flow imparting section 5 illustrated in FIG.
In the above, the ejector nozzle 52 is used to generate a parallel air flow, but a suction nozzle may be provided instead of the ejector nozzle. In the case of the ejector nozzle, it is provided on the upper side of the yarn path, but in the case of the suction nozzle, it is provided on the lower side of the yarn path.

The oil supply means 6 is composed of an oil supply roller 61, an oil trough 62, and a pressing roller 63. An oil film is formed on the surface of the oil supply roller 61 by partially immersing the oil supply roller 61 in the oil trough 62 and rotating the oil supply trough 62. With respect to the oil supply means 6, a plurality of spun filaments F are arranged in a row and come into contact with the surface of the oil supply roller 61.
By being pressed to the surface side of the, the oil agent is evenly applied to each of the plurality of spun filaments F.

In the embodiment of FIG. 1 described above, the straightening plate 41a provided in the cooling section 4 may be fixed in a fixed inclination angle, but as shown in FIG. 3, the inclination angle can be arbitrarily changed. May be adjustable. If the inclination angle of the current plate 41a is adjustable,
The inclination angle can be appropriately set according to the fineness and the number of the spun filaments F, or the type of the thermoplastic polymer constituting the spun filament F. Further, as shown in FIG. 3, the inclination angle of each straightening plate 41a can be set to be changed stepwise.

In the cooling unit 4, as in the embodiment of FIG. 1,
Besides providing the cooling air outlet 41, the cooling air suction port 42 on the opposite side may be provided, or may be omitted as in the embodiment shown in FIG. However, it is preferable to provide the cooling air suction port 42 as in the former case. By installing the cooling air suction port 42, the cooling air which has finished cooling the spun filament F is forcibly sucked, and at the same time, the monomer or oligomer evaporated from the spun filament F is forcibly sucked and removed, It is possible to solve various problems caused by these, such as deterioration of yarn quality.

That is, the monomers and oligomers evaporated from the spun filament F adhere to the yarn path on the downstream side, thereby hindering the running of the spun filament F,
Although problems such as quality reduction occur, these problems can be solved.

Further, as in the embodiment shown in FIG. 7, the yarn path 51 of the parallel air flow imparting section 5 is extended to the extension line L of the center line of the discharge hole 3.
It is more preferable that the position be offset horizontally by a distance e. Since the spun filament F cooled by the cooling air in the cooling unit 4 is in a state of being swept away in a curved shape, the yarn path 51 of the parallel airflow imparting unit 5 is arranged at the position of the extension line L of the discharge hole 3. Then, it is necessary to push back the downstream portion of the curved spinning filament F to the yarn path 51, and uneven stress that causes yarn unevenness may act on the spinning filament F.

However, as described above, the yarn path 51 is connected to the discharge hole 3
By offsetting from the extension line L in the blowing direction of the cooling air, the spun filament F is not overly stressed, the working stress is made uniform, and the yarn quality can be improved.

In the present invention, the blowing direction of the cooling air in the cooling section 4 is from one side in the arrangement direction of the spun filaments F to the yarn running direction of the spun filaments F as shown in FIGS. 1, 6 and 7. On the other hand, it should be diagonally downward. However, if necessary, as in the embodiment shown in FIG. 8, another cooling air outlet 41 ′ is provided on the side opposite to the arrangement direction on the further downstream side,
The cooling air supplied from the air supply port 43 'is supplied to the cooling air outlet 41'.
The yarn may be blown obliquely downward to the side opposite to the cooling wind blown from the cooling wind blowout port 41 in the yarn traveling direction. In any case, since there is an action of increasing the tension of the spun filament F up to the spinneret 2, the upper limit of the spinning speed at which yarn wobbling does not occur can be increased.

Further, the die used in the present invention may have a plurality of rows as shown in FIGS. 9 and 10. 2 in FIG.
Although a case of three rows is illustrated in FIG. 10, more rows may be used. At this time, in order to prevent the discharge holes themselves from approaching each other and fusion of the spun filaments, it is preferable to set the discharge holes in each row in a so-called staggered arrangement.

Further, the running direction of the spun filament is generally lined up at the upper part of the inlet of the parallel airflow imparting portion as shown in FIG. 11, but as shown in FIG. Good. By using such a plurality of rows of spinnerets, it is possible to manufacture a yarn having a larger number of single yarns.

[0045]

As described above, according to the present invention, since the cooling air is blown obliquely downward with respect to the yarn traveling direction to the filament melt-spun from the spinneret, the spun filament has the velocity energy of the cooling air. The velocity component given to the running direction of the spinning filament increases, and the tension of the spun filament increases. Therefore, even if the spinning speed is increased, the spinning state can be stabilized and the occurrence of yarn shaking can be suppressed.

Further, by providing a parallel air stream to the spun filament at the downstream side and pulling the filament, the spinning tension after the cooling treatment is relaxed and the progress of the orientation is suppressed, so that the yarn has less unevenness after the cooling treatment. High quality semi-drawn yarn (POY) is obtained. Further, since the cooling air is directed obliquely downward, it is possible to reduce the effect of lowering the temperature of the surface of the die, and further to reduce the occurrence of yarn unevenness and single yarn breakage.

[Brief description of drawings]

FIG. 1 is a schematic view of a synthetic fiber manufacturing apparatus of the present invention.

FIG. 2 is a bottom view of the mouthpiece as seen from the arrow XX of FIG.

FIG. 3 is a schematic view showing another example of the cooling unit in the device of the present invention.

FIG. 4 is a transverse cross-sectional view of the parallel airflow imparting section as seen from the direction of the arrows YY in FIG.

5 is a perspective view of an oil agent applying means in the apparatus of FIG.

FIG. 6 is a schematic view showing a main part of another aspect of the manufacturing apparatus of the present invention.

FIG. 7 is a schematic view showing a main part of still another aspect of the manufacturing apparatus of the present invention.

FIG. 8 is a schematic view showing a main part of still another aspect of the manufacturing apparatus of the present invention.

FIG. 9 is a plan view of another aspect of the die used in the present invention.

FIG. 10 is a plan view of still another embodiment of the die used in the present invention.

FIG. 11 is a schematic view showing a main part of still another aspect of the manufacturing apparatus of the present invention.

FIG. 12 is a schematic view showing a main part of still another aspect of the manufacturing apparatus of the present invention.

[Explanation of symbols]

2 clasp 3 discharge holes 4 Cooling unit 41 Cooling air outlet 42 Cooling air suction port 41a, 42a Current plate 5 Parallel air flow imparting section 51 Thread 6 Oil agent applying means 61 Refueling roller 9 First take-up roller 10 Second take-up roller 11 winder F Spinning filament

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yuuki Furuta             1-1 1-1 Sonoyama, Otsu City, Shiga Prefecture Toray Co., Ltd.             Ceremony company Shiga business site F-term (reference) 4L045 AA05 BA03 DA21 DA27

Claims (10)

[Claims] 1. A plurality of filaments are melt-spun from a spinneret having a plurality of discharge holes, and cooling air is blown obliquely downward to the spun filaments to cool the spun filaments. A method for producing a synthetic fiber that provides an air flow parallel to the running direction of a spun filament. 2. The synthesis according to claim 1, wherein the plurality of filaments are arranged in a row and melt-spun, and cooling air is blown obliquely downward from the side in the row direction to the spun filaments. Fiber manufacturing method. 3. The method for producing a synthetic fiber according to claim 1, wherein the cooling air is forcibly sucked on the opposite side of the spun filament. 4. The method for producing a synthetic fiber according to claim 2, wherein the oil agent is applied in a state where the spun filaments are arranged in rows. 5. A cooling section is provided below a spinning section provided with a spinneret having a plurality of discharge holes, and a cooling section for blowing cooling air obliquely downward to a filament to be melt-spun from the spinning section, further below the cooling section. An apparatus for producing synthetic fibers, further comprising a parallel airflow imparting section for imparting an airflow parallel to the filament running direction to the filament. 6. A plurality of discharge holes are provided in a row in the base,
6. A structure in which the blowing direction of the cooling air in the cooling unit is directed obliquely downward from the side in the filament arrangement direction to the filaments melt-spun in a row from the spinneret.
The synthetic fiber manufacturing apparatus described in 1. 7. The synthetic fiber manufacturing apparatus according to claim 5, wherein the blowing direction of the cooling air is adjustable. 8. The synthetic fiber manufacturing apparatus according to claim 5, further comprising a cooling air suction port sandwiching the spun filament so as to face the cooling air blowing port. 9. The synthetic fiber manufacturing apparatus according to claim 6, further comprising an oil supply section that arranges the spun filaments in a row and applies an oil agent. 10. The synthetic fiber manufacturing apparatus according to claim 5, wherein the yarn path of the parallel air flow imparting section is arranged at a position offset from an extension line passing through the center of the discharge hole.