JP2002242020A - Spinning nozzle pack for producing hollow fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spinning nozzle pack which is used for producing a hollow fiber, can highly precisely filter a highly viscous melted polymer and can spin the melted polymer in a state scarcely having the unevenness of temperature. SOLUTION: This spinning nozzle pack (10) for producing the hollow fiber has a circular extrusion slit (25), a gas-discharging hole (24a) disposed at the center of the circular extrusion slit (25), a distribution plate (21) for distributing a polymer to the slit (25), a gas-introducing chamber (23) for introducing a gas into the gas-discharging hole (24a), and a gas-supplying route (22b) for supplying the gas into the gas-introducing chamber (23). A disk laminate type leaf disk filter (31) is disposed in just front of the distribution plate (21) in a state that the center of the leaf disk filter (31) is supported on a center pole (32). The center pole (32) has a post portion (32a) having a flow passage for the filtered polymer and a flange (32b) extended in one end of the post portion (32a). The outer side of the flange (32b) forms a part of the outer wall of the nozzle pack (10). The outer wall has a heater to heat the post portion (32a) through the flange portion (32b).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spinning nozzle pack for producing hollow fibers from a meltable polymer by a melt shaping method.

[0002]

2. Description of the Related Art A spinning nozzle pack for producing hollow fibers is disclosed in, for example, Japanese Utility Model Laid-Open No. 57-39972.
A nozzle pack 100 as shown in FIG. 5 is used. The nozzle pack 100 includes an upper feeder 112
Molten resin flow path 11 formed from the side wall to the bottom
The resin supplied through 2a is introduced into the spinning nozzle unit 120 assembled in the lower casing 111 through the filter 130. The spinning nozzle unit 120 includes an annular discharge slit 25 that opens on the nozzle surface, a gas discharge hole 24a disposed at the center of the discharge slit 25, and a distribution plate 121 that distributes the molten polymer to the discharge slit 25. A gas introduction chamber 23 for introducing gas into the gas discharge hole 24a; and a gas supply passage 22b for supplying gas to the gas introduction chamber 23.

Conventionally, when producing a hollow fiber membrane by a melt shaping method, filtration of a molten polymer has been performed by a disk filter in which several wire meshes of about 50 to 1000 mesh are laminated. In the molten polymer, undissolved substances are present in addition to the contaminating impurities. By removing these by filtration, not only the spinning stability is improved, but also the hollow fibers produced by the melt shaping method. It has been confirmed that the stability when the film is stretched and made porous in the subsequent step is remarkably improved, and the yield is greatly improved.

Therefore, in order to enhance the filtration performance, a method of filling a metal sand on the upstream side of a wire mesh disk filter to filter and rectify a molten polymer, a method of using a metal nonwoven fabric disk filter, and the like have been studied. In addition, when filtering a polymer for a hollow fiber membrane having a relatively high melt viscosity, there is a problem that the filtration differential pressure increases and the existing spinning equipment cannot withstand this.

On the other hand, attempts have been made to increase the spinning speed for the purpose of improving the spinning productivity. However, the increase in the differential pressure of the filtration filter is limited, and the pressure resistance of the filter medium and the spinning equipment itself are reduced. In addition, the shear pressure of the polymer increases due to the increase in the differential pressure, the temperature unevenness of the polymer in the nozzle increases, the spinning speed cannot be sufficiently increased, and the spinning unevenness is caused.

[0006] In order to solve such a problem, C has been used in equipment for spinning polyester fibers for clothing.
Introducing PF (Central Polymer Filter), installing a large-scale high-performance filtration filter in the center for many spinning nozzle packs, and feeding polymer piping from the center filter to the spinning holes on the periphery Can be considered. However, in this CPF, the retention deterioration of the molten polymer tends to be a problem.

Furthermore, since the polymer for the hollow fiber membrane is a polymer having a relatively high melt viscosity exceeding tens of thousands of poise under the melt spinning temperature and spinning conditions, a large-scale filter is used in the nozzle for hollow fiber production. However, there is a problem that it is difficult to take a method of disposing the polymer pipe in the center and drawing and supplying the polymer pipe from the center filter to the spinning hole on the periphery. In addition, the existing spinning equipment requires significant equipment modification, which is not practical.

Further, as disclosed in Japanese Utility Model Laid-Open No. 63-140074, a polymer filtered at the center of a center pole, which is used in a melt-spinning nozzle pack for spinning a general solid yarn, is used. It is also conceivable to simply install the staying OUT-IN filtration type leaf disk filter in a spinning nozzle pack for hollow fiber production. However, in such a leaf disc filter, the residence time of the molten polymer in the nozzle pack increases, and therefore, the spinning stability itself may be impaired due to thermal deterioration of the polymer. In addition, the increase in the residence time of the molten polymer in the nozzle pack is reflected in the temperature unevenness of the polymer. Therefore, it is important to equalize the temperature inside the nozzle pack.However, the temperature of the central part of the nozzle pack heated from the surroundings is lower than that of other parts, and the temperature of the spinning nozzle surface exposed to the quench wind is reduced. It is lower than other parts. Therefore, it was impossible to use such an OUT-IN filtration type leaf disk filter except when spinning a polymer having an extremely low melt viscosity at a high speed.

In order to solve such a problem, a general spinning nozzle pack for melt spinning disclosed in Japanese Utility Model Laid-Open No. 5-56965 and Japanese Utility Model Laid-Open No. 5-771 has been proposed.
As a leaf disk filter installed in the nozzle pack, an IN-OUT filtration type leaf disk filter that supplies a molten polymer from a central portion and performs filtration toward the outer periphery of the filter has been proposed.
When such an IN-OUT filtration type leaf disk filter is used, a polymer nozzle is perforated on the periphery of the distribution plate, and the polymer filtered from the center of the filter toward the outer periphery is not focused on one place. In addition, spinning can be performed from a nozzle perforated at the periphery, where the temperature is relatively easy to control.

[0010]

However, a commercially available leaf disk filter has a structure on the premise that the OUT-IN filtration is performed from the periphery toward the center. When performing OUT filtration, the filter has a structure that cannot withstand high internal pressure.

Therefore, such an IN-OUT filtration type leaf disk filter can be applied only to a polymer having a very low melt viscosity, and can be used for filtering a high viscosity molten polymer used for hollow fiber membranes. When the filtration viscosity is high, the filtration itself may not be performed by narrowing the flow path by swelling or deforming the filtration media with respect to the internal pressure. That is, a general OUT-IN filtration type leaf disk filter having a pressure-resistant reinforcement inside is used for a spinning nozzle pack for a hollow fiber having a high melt viscosity, and vice versa. It is difficult.

The present invention has been made in view of such circumstances, and an object of the present invention is to integrate a filter of a molten polymer with an existing spinning nozzle pack for manufacturing a hollow fiber to make it compatible with conventional spinning equipment. An object of the present invention is to provide a spinning nozzle pack for producing a hollow fiber, which enables high-accuracy filtration of a molten polymer having a relatively high viscosity while allowing spinning of a molten polymer having less unevenness in temperature.

[0013]

According to the first aspect of the present invention, there is provided an annular discharge slit opening on a nozzle surface and a gas discharge disposed at the center of the discharge slit. A hollow fiber producing spinning device having a hole, a distribution plate for distributing the molten polymer to the discharge slit, a gas introduction chamber for introducing gas into the gas discharge hole, and a gas supply path for supplying gas to the gas introduction chamber. In the nozzle pack, a disk-laminated leaf disk filter is disposed immediately before the distribution plate with its center supported by a center pole. A post having a flow path, and a flange extending perpendicularly from one end of the post, the outer surface of the flange is a nozzle pack Is characterized by comprising constitutes part of the outer wall.

Further, in the invention according to the second aspect of the present invention, a heater is provided on the outer wall, and the post is heated via the flange.

According to the present invention, even if the molten polymer for a hollow fiber has a high viscosity, it can be filtered with high accuracy by a leaf disk filter of OUT-IN filtration, and even if the time required for filtration becomes long. Since the center pole post located in the center of the filter is heated to the same degree as the outer wall, there is little temperature unevenness of the filtered polymer, and high-performance hollow fiber can be stably spun. Will be possible.

According to the third aspect of the present invention,
The gas supply path is open to the nozzle surface, and a heat insulating plate having a polymer spinning hole and a gas supply opening at portions corresponding to the discharge slit and the gas supply path is provided on the nozzle surface. It is characterized by. In this way, by installing the heat insulating plate on the nozzle surface of the nozzle pack, it is possible to minimize the influence of the quench wind on the nozzle surface and achieve stable spinning.

The invention according to claim 4 of the present invention is further characterized in that a heater is installed near the nozzle surface. The temperature of the nozzle surface is likely to be lower than that of other parts due to the influence of the quench wind.However, by heating the vicinity of the nozzle surface with a heater, the temperature difference with other parts is minimized, and the nozzle pack is A uniform temperature distribution can be obtained throughout, and more stable spinning of the molten polymer becomes possible.

The invention according to claim 5 is characterized in that a static mixer is arranged inside the post portion of the center pole. If a static mixer is arranged in the post section, the filtered molten polymer is stirred by the mixer, and the temperature of the molten polymer can be further uniformed.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a view schematically showing a spinning nozzle pack for producing a hollow fiber, which is a preferred embodiment of the present invention.

The nozzle pack 1 includes a lower casing 11
A hollow fiber spinning nozzle unit 20 is incorporated therein, and a leaf disc filter unit 30 is incorporated in the upper feeder 12.

The lower casing 11 is formed of a cylindrical body,
The spinning nozzle unit 20 is assembled at the center. At the lower end of the casing 11, a tapered portion 11a whose inner peripheral surface expands downward is formed.

The spinning nozzle unit 20 has a distribution plate 21 closely fitted to the upper end of the casing 11. The distribution plate 21 has a plurality of inverted funnel-shaped distribution holes 21a penetrating up and down at the peripheral edge thereof and having a diameter increasing downward. Further, the upper surface of the distribution plate 21 is located at the center of the distribution hole 21 from the center.
The distribution surface 21b is inclined toward a.

Below the distribution plate 21, a nozzle body 22 is closely fitted to the casing 11 with a predetermined gap. The space between the distribution plate 21 and the nozzle body 22 constitutes a gas introduction chamber 23. The nozzle body 22 has a plurality of nozzle through-holes 22a and a plurality of gas supply passages 22b communicating with the gas introduction chamber 23. The nozzle body 22 is positioned so that the nozzle through-hole 22a is located at the position where the distribution hole 21a of the distribution plate 21 is formed.
Is fixed by a pin member 13.

The gas supply passage 22b is connected to the nozzle body 22
Is provided appropriately in a portion other than the nozzle through-hole 22a, so that there is no large difference in cross-sectional area with a gas discharge hole 24a formed in a nozzle core 24 described later, so that gas can be introduced into the gas introduction chamber 23 without great resistance. The size and the number are not limited to FIG. The gas supply passage 22b is also formed at the center of the nozzle body 22 in the nozzle pack 1 of FIG. 1, but the gas supply path 22b is formed at the center of the nozzle body 22 in consideration of the temperature unevenness of the entire nozzle pack. The supply path 22b may not be formed.

A nozzle core 24 is inserted into the nozzle through hole 22a of the nozzle body. The nozzle core 2
Reference numeral 4 denotes a gasket 14 having an upper part protruding into the gas introduction chamber and an upper end provided on a periphery of the distribution hole 21 a of the distribution plate 21.
Are in close contact with each other. Further, the nozzle core 24 closely fits over the nozzle through-hole 22a of the nozzle body 22, and the nozzle core 24 fits under the through-hole 22a.
An annular discharge slit 25 is formed between the outer peripheral surface of the base member and the through hole 22a. A hollow fiber is spun from the lower end of the discharge slit 25. Nozzle core 2
4 is formed with a gas discharge hole 24a communicating from the upper side exposed to the gas introduction chamber to the lower end.

The upper feeder 12 has a leaf disc filter unit 3 in the center thereof, the lower end of which is open.
0 storage space 12a is formed. Further, the feeder 12 is formed with a molten polymer introduction path 12b communicating with the storage space 12a, and the introduction path 12b has a molten polymer introduction opening 12c in the upper part of the side wall of the feeder 12.

The leaf disk filter unit 3
Numeral 0 indicates that a plurality of disk-shaped leaf disk filters 31 are stacked and supported by a center post 32 with a gasket and a SUS ring interposed therebetween. The center post 32 includes a cylindrical post portion 32a and a flange portion 32b extending orthogonally from a lower end of the post portion 32a.
A large number of polymer openings 32c are formed in the post portion 32a.

The leaf disk filter 31 laminated and supported by the center post 32 is compressed from above by a cover plate 33, and is fixed by a bolt 34 at the upper end of a post portion 32a of the center post 32.

The leaf disk filter 31 is exactly the same in structure as a commercially available one, and is of a type that filters out from the periphery of the disk toward the center with OUT-IN, but is integrated into the nozzle pack. The diameter is selected so that it can be incorporated. The number of stacked leaf disc filters 31 is determined by the relationship between the required filtration area determined from the filtration accuracy and the filter material life, and the size of the nozzle pack 1 and the leaf disc filter unit 30.

In the present invention, the center post 32
There is a feature. That is, the center post used in the conventional leaf disc filter unit 30 is:
The extension length of the flange portion extending perpendicularly from the lower end of the post portion is slightly longer than the diameter of the leaf disc filter to support the post portion and the leaf disc filter, It is stored in the pack casing.

However, the center post 3 of the present invention
2 is the lower casing 11 and the upper feeder 12 of the filter unit 1 when the extension length of the flange 32b is extended.
Is set to a length that forms the same plane as the outer circumference of the. Therefore, the upper portion of the lower casing 11 in which the above-described spinning nozzle unit 20 is incorporated is closed by the gasket 15 by the flange portion 32b of the center post 32, and the upper feeder 12 in which the leaf disc filter 30 is incorporated is provided. The storage space 11 a is closed via the gasket 16. Then, the lower casing 11, the upper feeder 12, and the flange portion 32 b of the center post 32 sandwiched therebetween are tightened by the bolt 17.

In order to manufacture a hollow fiber using the nozzle pack 1 having such a configuration, first, a molten polymer is introduced from the molten polymer introduction opening 12c of the upper feeder 12, and the leaf filter unit 30 is passed through the molten polymer introduction passage 12b. To the storage space 12a. The storage space 12a and the leaf disc filter unit 30
After the molten polymer filled in the gap is filtered by the leaf disc filter 31, the center post 3
The liquid is immediately led to the distribution plate 21 of the spinning nozzle unit 20 without staying through the post portion 32a from the second polymer opening 32c.

At this time, the nozzle pack 1 is heated to a predetermined temperature from the outside. Usually, the post portion 32a of the center post 32 located at the center of the leaf disc filter unit 30 is furthest from the outer peripheral portion. Therefore, it is difficult to control the temperature, and a large temperature distribution is given to the molten polymer staying in this portion.

However, according to the present invention, since the flange portion 32b of the center post 32 that supports the leaf disc filter 31 forms a part of the outer wall of the nozzle pack 1, the center post 32 is attached to the nozzle pack 1 during spinning. Heated directly from the side. The direct heat conduction to the center post 32 causes the upper feeder 12
Part 32a of center post 32 located at the center of
Similarly, the lower casing and the upper feeder 12 are directly heated, so that the temperature difference between the vicinity of the outer wall of the nozzle pack 1 and the post 32a at the center of the leaf disc filter unit 30 is extremely small.

For this reason, the molten polymer for the hollow fiber membrane has a high viscosity,
Although the residence time within 0 is relatively long, not only the outer wall but also the central post portion 32a is heated, so that the temperature unevenness of the molten polymer can be minimized. Further, the staying portion of the center post 32 is designed to be as small as possible to minimize the staying time, so that the temperature unevenness can be reduced.

Thereafter, the filtered molten polymer is distributed to the distribution holes 21a of the spinning nozzle unit 20, but the distribution plate 21 on which the molten polymer abuts and stays has a distribution surface 21b inclined toward the outer periphery. Therefore, the distribution of the polymer is smoothly performed, and it is effective to assist in reducing the temperature unevenness.

The molten polymer passes through each discharge slit 25 and is spun as a hollow fiber from a spinning hole 25a at the lower end thereof. At this time, the gas introduction passage 2
The gas introduced into 3 passes through the gas discharge hole 24a of the nozzle core 7 and is introduced into the inside of the hollow polymer spun from the discharge slit 25, and the hollow fiber is spun. During the spinning, the molten polymer has no temperature unevenness, so that uniform and stable spinning can be performed.

Of course, the configuration of the nozzle pack 1 described above is merely an example of the present invention, and the design of the auxiliary nozzle pack is not limited to these.

For example, the discharge slit 25 radiates heat under the influence of a quench wind depending on the spinning conditions, and this increases the temperature unevenness of the entire nozzle pack 1. Therefore, at the lower end of the nozzle body 22, that is, at the nozzle surface,
It is preferable to install a heat insulating plate 26 as shown in FIG. By providing such a cross-section plate 26, heat radiation from the nozzle surface can be suppressed, and the temperature of the entire nozzle pack can be made uniform.

The heat insulating plate 26 has a spinning hole 26a having the same diameter as the discharge slit 25 for spinning hollow fibers, and a gas introduction opening 26b having the same diameter as the gas supply passage 22b. By providing a pin hole or the like for positioning the nozzle body 22 in the circumferential direction, the nozzle body 22 can be easily assembled to the nozzle body 22. The spinning hole 26a is a stepped hole,
In the vicinity of the discharge slit 25, the heat insulating plate 26 is prevented from directly contacting the lower surface (nozzle surface) of the nozzle body 22, thereby further enhancing the heat insulating effect. The material of the heat insulating plate 26 is not particularly limited as long as it can withstand the temperature of the nozzle pack 1 at the time of spinning or preheating, but the same material as the material of the nozzle pack 1 is used in consideration of thermal expansion and cleaning. It is more preferable to use.

In order to suppress the influence of the quench wind,
Attaching a band heater 27 as shown in FIG. 3 to the lower end portion of the lower casing 11 of the nozzle pack 1 shown in FIG. 1 to actively control the temperature is also effective in making the temperature of the entire nozzle pack uniform. It is. The band heater 27 has a ring shape with a part thereof separated, and a screw member 2 for adjusting a gap in the separated part and tightening and fixing the band heater 27 to the lower end of the lower casing 11 of the nozzle pack 1.
7a is attached. Therefore, the size of the band heater 27 can be appropriately adjusted and fixed according to the size of the lower end of the lower casing.

The band heater 27 is not limited to the one shown in FIG. 3. However, in order to install the nozzle pack 1 integrally and use it in a manner compatible with the conventional spinning nozzle pack, FIG. More desirably, the casing 11 can be installed at the lower end portion of the lower casing 11 so as to be cut by the thickness of the hand heater.

The band heater 27 is not particularly limited as long as it satisfies the operating temperature range and the control accuracy conditions. The band heater 27 performs auxiliary temperature control similarly to the lip heater used in a T-die or the like of a film manufacturing apparatus. is there.

According to the nozzle pack 1 described above, the temperature of the entire nozzle pack 1 can be made uniform. However, compared to the conventional nozzle pack using a disk filter, the nozzle pack 1 of the molten polymer is used. I have to spend a long time inside. Therefore, spinning stability may be impaired for a polymer having particularly large temperature dependence of polymer viscosity or a polymer sensitive to heat history.

FIG. 4 shows a nozzle pack 1 'improved to solve such a problem. The nozzle pack 1 'has a point that the static mixer 35 is installed in the post portion 32a of the center post 32 of the leaf filter unit 30', and the upper surface of the distribution plate 21 'has a flat surface 21b'.
Is the same as that of the nozzle pack 1 except that it is different from the nozzle pack 1. Therefore, the same components as those of the nozzle pack 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

The post part 32a of the center post 32
By installing the static mixer 35 inside
Since the molten polymer after filtration can be positively and uniformly mixed, stable spinning can be performed. In addition, when the polymer after filtration is homogenized by the static mixer 35, the polymer pressure at the time of spinning is increased, so that the filtration pressure difference, the pressure difference of the entire nozzle pack 1 ',
Static mixer 3 while adjusting the degree of uniform mixing
It is necessary to determine the number of steps of 5 within the dimensional tolerance in the pack 1.

Hereinafter, the present invention will be specifically described with reference to examples. (Example 1) A spinning nozzle pack for producing hollow fibers as shown in Fig. 1 was prepared. The specifications of the leaf disc filter are as follows. Leaf disk filter Metal non-woven fabric / Naslon LF2M08D1 (95% filtration accuracy 20μ) Diameter φ78-30, manufactured by Nippon Seisen Co., Ltd. Nine pieces Total filtration area 0.0432m ² Center pole inner diameter: φ10mm Spinning nozzle for this hollow fiber production The molten polymer was supplied by the pack under the following spinning conditions, and the hollow fiber was spun. Spinning conditions Polymer: high-density polyethylene (HIZEX: manufactured by Mitsui Chemicals) Spinning temperature: 160 ° C. Discharge rate: 75.06 cc / min Nozzle pack pressure: 6.0 MPa Spinning speed: 200 m / min Quenching condition: blowing temperature 16 ° C., air volume appropriate Adjustment

As a result, the temperature of the discharged resin could be stably controlled at about 156 ° C., and the spinning could be stably performed. Also, the diameter (knot), which is a control item during spinning, was stable, and no yarn breakage occurred. Furthermore, in the subsequent stretching step, the yarn breakage rate considered to be due to spinning defects was on the order of 3%, which could be reduced to half that of the conventional nozzle pack. Further, even after 50 hours of the normal spinning time, the pressure rise of the nozzle pack is very small at 0.1 MPa, and there is no problem regarding the nozzle life due to the increase in the differential pressure, and the spinning is continued. It was possible.

Comparative Example 1 A conventional spinning nozzle pack 100 for producing hollow fibers using the disk filter shown in FIG.
Thus, a hollow fiber was spun under substantially the same spinning conditions as in Example 1 described above. The nozzle pack 100 is arranged such that the molten resin flow path 11
2a is formed. The spinning nozzle unit 120 and the disc filter 130 are assembled to the lower casing 111. The spinning nozzle unit 120
Is the same as the above-described spinning nozzle unit 20 of the nozzle pack 1 of the present invention except for the distribution plate 121, and the same members are denoted by the same reference numerals and detailed description thereof will be omitted.

The distributing plate 121 is different from the distributing plate 21 in that the upper end thereof has a supporting step 121a for the disk filter 130, and the lower portion has a space 121b in which the filtered polymer is dropped. However, the other configuration is the same, the bottom surface of the space 121b is a distribution surface 121c inclined from the center to the outer periphery, and a distribution path 121d for the molten polymer is formed on the outer periphery.
The disk filter 130 used here had the following specifications. Disc filter SUS wire mesh 9 layer (# 50, # 100, # 325, # 6
00, # 1000, # 325, # 100, # 50, # 1
0) Diameter 75 mm, manufactured by Kansai Wire Mesh Co., Ltd. 95% filtration accuracy: 51 μm Filtration area: 0.0049 m ²

As a result, it was possible to spin at a spinning speed of 190 m / min. Nozzle pack pressure is 11M
Pa, the temperature of the discharged resin was about 152 ° C., and it took about 2 hours to be stabilized. In addition, the defect rate in the diameter (knuckle), which is a control item at the time of spinning, was 4%. Further, in the subsequent drawing step, the yarn breakage rate which was considered to be caused by spinning defects was about 7%. The differential pressure rise of the nozzle pack is about 5 MPa after a normal spinning time of 50 hours,
It was difficult to extend the service life significantly.

As described above, in the spinning nozzle pack for manufacturing a hollow fiber according to the present invention, since the outer peripheral surface of the nozzle pack is constituted by the flange portion of the center post in the leaf filter unit, the direct heat from this flange portion is formed. Due to the conduction, the central post is also heated, and the molten polymer staying in the post is also heated and its temperature can be controlled. Therefore, it is possible to minimize the temperature unevenness of the molten polymer staying in the post portion, make the temperature of the molten polymer uniform, and stably produce the hollow fiber by spinning.

Further, the spinning nozzle pack for producing hollow fibers of the present invention can be made completely compatible with the conventional nozzle pack, and can be used with high precision without changing existing spinning equipment at all. It becomes possible to perform filtration. This not only makes it possible to lower the spinning pressure of the polymer, which has been the limiting factor in improving the spinning speed, but also extends the life of the nozzle pack, and only stabilizes the quality of the hollow fiber membrane. Rather, it has a special effect of greatly improving productivity.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a spinning nozzle pack for manufacturing a hollow fiber according to a preferred embodiment of the present invention.

FIG. 2 is a perspective view of a heat insulating plate arranged on a nozzle surface of the spinning nozzle pack for manufacturing a hollow fiber of FIG. 1;

FIG. 3 is a top view and a side view showing an example of a band heater additionally mounted on the spinning nozzle pack for manufacturing a hollow fiber of FIG. 1;

FIG. 4 is a sectional view of a spinning nozzle pack for producing a hollow fiber according to a preferred modification of the present invention.

FIG. 5 is a sectional view of a conventional spinning nozzle pack for producing hollow fibers.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Spun nozzle pack for hollow fiber manufacture 11 Lower casing 11a Taper part 12 Upper feeder 12a Storage space of leaf disc filter unit 12b Melted polymer introduction path 12c Melted polymer introduction opening 13 Pin member 14 Gasket 20 Spinning nozzle unit 21 Distribution plate 21a Distribution hole 21b Distribution surface 22 Nozzle main body 22a Nozzle through hole 22b Gas supply path 23 Gas introduction chamber 24 Nozzle core 24a Gas exhaust hole 25 Discharge slit 26 Insulating plate 26a Spinning hole 26b Gas introduction opening 27 Band heater 30 Leaf disk filter unit 31 Leaf Disc filter 32 Center post 32a Post part 32b Flange part 32c Opening for polymer 33 Cover plate 34 Bolt 35 Static mixer

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4D006 MA01 MC22 MC22X NA28 NA75 4L045 AA05 BA24 CA06 CA08 CA12 CA32 DA60

Claims (5)

[Claims] 1. An annular discharge slit opening on a nozzle surface and a gas discharge hole disposed at the center of the discharge slit,
A distribution plate for distributing the molten polymer to the discharge slit,
In a spinning nozzle pack for manufacturing a hollow fiber having a gas introduction chamber for introducing a gas into the gas discharge hole and a gas supply path for supplying a gas to the gas introduction chamber, a disc-type leaf disk filter is provided with the distribution plate. Immediately before, the center is supported by a center pole, and the center pole is orthogonal to one end of the post having a flow path of the molten polymer filtered by the leaf disk filter on a central axis and one end of the post. And a flange portion extending and extending, wherein an outer surface of the flange portion constitutes a part of an outer wall of the nozzle pack. 2. The spinning nozzle pack for producing a hollow fiber according to claim 1, wherein a heater is provided on the outer wall, and the post portion is heated via the flange portion. 3. The gas supply passage is open to the nozzle surface, and a heat insulating plate having a polymer spinning hole and a gas supply opening at a portion corresponding to the discharge slit and the gas supply passage is provided on the nozzle surface. The spinning nozzle pack for producing hollow fibers according to claim 1 or 2, wherein the spinning nozzle pack is provided. 4. The spinning nozzle pack according to claim 2, further comprising a heater installed near the nozzle surface. 5. The spinning nozzle pack for producing hollow fibers according to claim 1, wherein a static mixer is disposed inside the post portion of the center pole.