JP5430405B2 - Method for producing hollow continuum - Google Patents

Description

    The present invention relates to a method for producing a hollow continuous body used as a support for producing a hollow fiber membrane or a hollow fiber membrane.

In recent years, interest in environmental pollution has increased, and various environmental laws have been strengthened, and countermeasures are being promoted in various fields. For example, in the field of water treatment, treatment using a small filtration membrane is being studied in order to highly separate contaminants.
By the way, when using a filtration membrane for water treatment, high mechanical properties (for example, pressure resistance, tensile strength, etc.) are required. As a method for producing a porous filtration membrane having excellent mechanical strength, a method for producing a hollow fiber membrane using a hollow round braid as a hollow fiber membrane support has been proposed (Patent Document 1, 2 and 3). Specifically, in this production method, a hollow fiber membrane production support is sent out from the center hole of the annular nozzle, and the membrane is spun from the outer circumference of the annular nozzle to the outer circumference of the hollow fiber membrane production support. The stock solution is applied and solidified to obtain a hollow fiber membrane.
In the above production method, in order to obtain a long hollow fiber membrane, the support for producing a hollow fiber membrane also needs to be long. Usually, the length of the support for producing the hollow fiber membrane is a hollow fiber. Because it is shorter than the desired length of the membrane, multiple supports must be joined.
In the manufacturing process of the hollow fiber membrane, there is a passing portion close to the outer diameter of the hollow fiber membrane and closed like a pipe during the passing step. For this reason, if a continuous body made by linking the supports for manufacturing hollow fiber membranes is used, the outer diameter of the joint becomes larger than other parts, so the process passes through the process while continuously running the hollow fiber membrane. It becomes difficult to make it.

  As a method for joining the hollow fiber membrane production supports, for example, a method using a known splicer is known. However, in the joining method using a splicer, it is difficult to properly join the supports for manufacturing the hollow fiber membranes because skilled techniques are required, and if these are not properly joined, the joining strength Problems such as shortage and enlargement of the joint diameter occur. As a result, the joint portion of the support for manufacturing the hollow fiber membrane is clogged or caught in the center hole of the annular nozzle, and the stability of the manufacturing process is lowered.

By the way, various methods have been proposed so far for the solid string member joining method. For example, Patent Document 4 discloses that a plastic round string is overlapped or twisted in parallel, and partially heat-pressed at regular intervals to alternately form heat-bonded portions and non-heat-bonded portions. There has been proposed a method of joining the two.
However, when the joining method described in Patent Document 4 is applied to a hollow object such as a support for manufacturing a hollow fiber membrane, the heat-sealed portion is slightly smaller than the combined size of the two hollow objects. In addition, the non-heat-sealed portion has a size obtained by combining two hollow objects. Therefore, in the joining method described in Patent Document 4, a step is formed on the side surface after joining, and when the obtained continuous body is passed through a portion where the outer diameter is regulated, such as the center hole of the annular nozzle, Clogging and catching occur, and the production stability of the hollow fiber membrane is reduced.

  In addition, a method has been proposed in which after knitting an elastic string body, the stitches are folded and overlapped, and fused by ultrasonic vibration or heating (see Patent Document 5). However, the fusion in Patent Document 5 does not join two string bodies to obtain one continuous body. Further, since the object to be fused is a solid string, a step is formed on any part of the side surface after joining.

  On the other hand, a method has been proposed in which a core material is inserted into a hollow portion of a hollow material, and the core material and the hollow material are ultrasonically fused (see Patent Document 6). However, in the joining method in Patent Document 6, it is necessary to join the end portions in order to obtain a desired joining strength, so that the joining portion becomes long. In addition, since the core material is inserted into the hollow portion, the flexibility of the hollow material at the joint portion is reduced. Such a decrease in the flexibility of the joint is caused by a decrease in the followability to the guide when the rotating guide or the fixed guide travels, which is used for changing the traveling direction when continuously traveling the hollow object. Will interfere with the stable running of the car. In particular, there is a concern that the longer the bonding length, the greater the effect. In addition, a core material is required separately, and the load in terms of cost and operability may be increased.

Japanese Patent Laid-Open No. 52-81076 JP-A-5-7746 WO04 / 43579 pamphlet Japanese Patent Laid-Open No. 50-4358 Japanese Patent No. 2962243 JP 2008-105014 A

  The object of the present invention is to prevent hollow fiber membrane production methods such as lack of bonding strength and increase in the diameter of the joining portion of hollow materials represented by a support, and to produce hollow fiber membranes without greatly impairing flexibility. Another object of the present invention is to provide a method for producing a hollow continuum in which deterioration in process stability during processing is prevented.

Gist of the present invention, a pair of hollow material, arranged so that its ends are in contact with the outer peripheral surface of each other, or the respective ends in contact with the outer peripheral surface of said end portion to one of the connecting members After being arranged in this manner, the entire end portion is compressed and deformed, and then the hollow continuous body is joined.

  According to the method for producing a hollow continuous body of the present invention, it is possible to prevent problems such as insufficient joining strength and an increase in diameter of the joined portion of the hollow article, and at the time of hollow fiber membrane production and processing without greatly impairing flexibility. A hollow continuous body in which a decrease in process stability is prevented can be produced.

It is a perspective view which shows the connection apparatus used by one Embodiment of the manufacturing method of the hollow continuous body of this invention. It is a figure which shows the state which inserted the hollow thing adjacent to the connection jig. It is sectional drawing which shows the aspect which inserted the edge part of a pair of hollow thing into the groove | channel of the connection jig. It is sectional drawing which shows the aspect which compression-deformed the edge part of a pair of hollow thing inserted in the groove | channel with the ultrasonic horn.

The hollow material referred to in the present invention is a material having a continuous space along the longitudinal direction, so that the inside of the fiber, the solid monofilament or the multifilament becomes hollow. There are woven or knitted fabrics, porous bodies having continuous or discontinuous voids such as sponge, and more specifically, hollow fibers, hollow braids, hollow knitted cords, hollow fiber membranes, etc. .
The shape of the hollow portion is not particularly limited, but a substantially circular shape is preferable. Although the outer diameter of a hollow thing is not specifically limited, 0.5-5 mm is preferable. The inner diameter is preferably 0.2 to 4 mm. The inner diameter is determined so that the volume of the hollow part of the hollow object is 10 to 90%, preferably 20 to 80% of the volume of the hollow object obtained from the outer diameter of the hollow object. Is preferred.

The material of the hollow material is not particularly limited, but a material that can be fused is preferable. Specific examples include polyethylene terephthalate, nylon, polyethylene, polypropylene, polyvinyl chloride, polysulfone, polyacrylonitrile, cellulose acetate, and polyvinylidene fluoride. These may be used alone or in combination.
The pair of hollow objects may be made of the same material, may be different, or may be a combination of these.

In the present invention, the pair of hollow objects are arranged such that the end portions thereof are in contact with each other, or each end portion is in contact with one connecting member on the outer peripheral surface thereof.
When arranging a pair of hollow objects so that the ends thereof are in contact with each other, the length of the contact portion in the yarn length direction of the contact portion is appropriately determined according to the desired bonding strength and flexibility after bonding. However, in consideration of the stability when the obtained hollow continuous body is repeatedly used, (the length A (mm) of the contact portion in the yarn length direction) / (the respective outer diameters of the pair of hollow materials Of these, the ratio of the larger outer diameter (mm) is preferably 1 or more. When this ratio exceeds 30, the force required for deforming the hollow object during joining increases, and the joining apparatus tends to increase in size.
Furthermore, the part where the hollow object is joined is more rigid than the other part, and when the hollow continuous body is run along the guide or the like, the joint part is lifted from the guide surface, and the hollow object is guided. There is a risk of losing.
Accordingly, the length A of the contact portion that will later correspond to the length of the joining portion is preferably in the range of 5 mm to 1550 mm, more preferably 5 mm to 100 mm, and most preferably 10 mm to 40 mm. By making the length of the contact part in the above-described range and joining this part, a hollow continuous body having high joint strength and excellent flexibility can be obtained.
Furthermore, when the hollow objects are brought into contact with each other, a hollow continuous body having no step on the side surface can be easily manufactured, so that the axial centers of the ends of the hollow objects are on the same straight line along the vertical direction. It is preferable to make contact.

Hereinafter, a case where a pair of hollow objects are arranged so that each end portion contacts one connection member on the outer peripheral surface thereof will be described.
The connecting member is a member for joining hollow objects, and can be easily joined to the hollow object, and is necessary for stably passing through the hollow fiber membrane manufacturing process and processing process. Those capable of maintaining strength and flexibility are preferred. Specifically, fiber bundles, hollow or solid braids, hollow or solid braids, strips of fiber knitted fabric, porous rods, porous strips, etc. Is mentioned. Further, when compressing and deforming the joint portion to join, a hollow continuous body having no step on the side surface is obtained, and as the connecting member, a material having a large volume reduction rate at the time of compressive deformation is preferable. , Hollow fiber bundles, hollow braids, hollow braids, hollow fiber membranes, hollow porous materials, hollow nets, tubes and the like.
As the connecting member, it is preferable to use a member made of the same material as the hollow material to be joined in terms of thermal characteristics and chemical resistance.
The connecting member is disposed so as to be in contact with each end portion of the pair of hollow objects and the outer peripheral surface thereof.
In this case, since the contact portion becomes the connection portion, in order to make an effective connection, it is preferable that the contact surface is made large and is closely attached so that a gap is not generated as much as possible.

In the present invention, after arranging a pair of hollow objects so that the end portions thereof are in contact with each other or each end portion is in contact with one connecting member on the outer peripheral surface thereof, the end portions thereof Is compressed and deformed.
A method of compressing and deforming is not particularly limited, and examples thereof include a method of applying a constant load with a weight, an air cylinder, or the like. In particular, when an air cylinder is used, the load to be applied can be changed by increasing or decreasing the supply air pressure, and the load supply and removal can be easily performed by reversing the cylinder supply direction of the supply air with a valve or the like.

In the present invention, after compressing and deforming the ends of the hollow objects, the hollow objects or the hollow object and the joining member are joined.
Examples of the bonding method include a bonding method using an adhesive and a bonding method using fusion.
When joining with an adhesive, the method is not particularly limited. For example, after applying an appropriate amount of adhesive to the connection surfaces of the hollow objects or between the hollow object and the joining member, it is inserted into the connection jig and compressed and deformed. Examples include a method of curing the adhesive while it is left and joining it into a desired shape. Examples of the adhesive used include a solvent evaporation type, a hot melt type, and a reaction curing type. Moreover, what is necessary is just to select an adhesive agent suitably according to desired conditions, such as connection time, a softness | flexibility, and connection strength. In addition, the amount of adhesive used for bonding is such that when the bonded portion is compressed and deformed, the adhesive sufficiently permeates between the hollow objects or the bonding surfaces of the hollow object and the bonding member, and a large amount from the bonding surface to the outside. It is preferable to select an amount that does not flow out to the connection jig and adhere to the connection jig according to the porosity of the hollow object or the joining member. Further, when the adhesive adheres and hardens on the inner surface of the connection jig, it is preferable to perform a releasable surface treatment such as a fluorine resin coating so that the bonded portion and the connection jig can be easily separated.
When joining by fusion, the method is not particularly limited. For example, a method in which a heated connection jig is compressed and deformed while being directly in contact with a hollow object, and is fused and joined to a desired shape, or is not heated in advance. For example, there may be mentioned a method of compressing and deforming with a connecting jig and then bringing it into contact with a heated connecting jig for fusing and joining. For example, when fusing polyethylene terephthalate, the heating temperature at that time is preferably about 250 ° C. to 280 ° C., which is a temperature near the melting point. In addition, the term “fusion” as used in the present invention refers to a state in which a part or all of a portion where the ends of a pair of hollow objects are overlapped is melted. In addition, on the inner surface of the connecting jig, a peelable surface treatment is performed so that the bonded portion and the connecting jig can be easily separated in preparation for the case where the hollow objects melted at the time of fusion or the bonding member adhere and cool and solidify. When the fusing temperature is high, it is preferable to perform a heat-resistant peelable surface treatment.
When joining by fusion, it is necessary to cool the connection jig once because the shape of the fusion product is not fixed if the connection jig heated in the fused state is released, but fusion is performed by ultrasonic fusion. Since ultrasonic horns, connection jigs and the like are not heated and can be processed for a short time, it is most preferable to perform fusion using ultrasonic waves. In the case of ultrasonic fusion, since the temperature of the connecting jig does not rise, the peelable surface treatment of the inner surface of the connecting jig can use a normal fluorine resin coating.

Hereinafter, a production example in the case of performing ultrasonic fusion will be specifically described.
In this production example, in order to compress and deform the entire ends of a pair of adjacent hollow objects so that the ends overlap each other, an ultrasonic horn 1 as shown in FIG. 1 and FIG. A connection device comprising a connection jig 2 is used.
In the ultrasonic horn 1 of this production example, the lower surface 1a is a surface in contact with the hollow objects 3a and 3b, and ultrasonic waves are transmitted from the lower surface to the hollow objects 3a and 3b.
The connection jig 2 of the present manufacturing example is a rectangular plate, and a groove 2a is linearly formed from one side of the plate to a side opposite to the side. The depth of the groove 2a is a pair of hollow plates. The articles 3a and 3b can be stacked and stored.
In the fusion using the ultrasonic horn 1 and the connecting jig 2, the end portions 3c and 3d of the hollow objects are respectively inserted into the grooves 2a of the connecting jig 2, as shown in FIG. As shown, the end of the ultrasonic horn 1 is inserted into the groove 2a and the end portions 3c, 3d are pressed against the bottom of the groove 2a, and the hollow objects 3a, 3b adjacent so that the end portions 3c, 3d overlap each other. The end portions 3c and 3d are compressed and deformed. Then, while maintaining the compression deformation state, ultrasonic waves are transmitted from the ultrasonic horn 1 to the end portions 3c and 3d of the adjacent hollow objects 3a and 3b to be fused.
When the hollow objects 3a and 3b are fused together using the ultrasonic horn 1, local heat generation occurs due to friction at the contact portions of the hollow objects 3a and 3b, and the bonded parts are thermally deformed and fused. Or the oxide layer on the surface disappears and the interface is activated to form intermolecular bonds. Therefore, even in a wet state where water or other liquid exists between the fibers of the hollow materials 3a and 3b or in the porous portion, the liquid melts. Evaporation and movement from the adhesion interface enable fusion.

In this compressive deformation, the process stability of the resulting hollow continuous body becomes higher, and therefore, the cross section perpendicular to the length direction of the portion where the ends of the pair of hollow objects overlap each other after the compressive deformation is obtained. The shape (hereinafter referred to as a cross-sectional shape) is preferably substantially the same as the cross-sectional shape of one hollow object before being compressed and deformed, that is, approximately circular.
In order to make the cross-sectional shape of the portion where the ends of the pair of hollow objects overlap after compression deformation substantially the same as the cross-sectional shape of one hollow object before compression deformation, for example, in FIG. As shown, a method using an ultrasonic horn 1 in which a groove recessed in an arc shape is formed on the lower surface 1 a and a connection jig 2 in which a U-shaped groove 2 a is formed can be employed. When the ultrasonic horn 1 is inserted into the groove 2a of the connecting jig 2, a hollow portion having a substantially circular cross section is formed.
When the connection jig 2 and the ultrasonic horn 1 are used, a minute gap is generated between them, and a burr-like thing may be formed after ultrasonic fusion. A burr-like thing may be generated.

  When the ultrasonic horn 1 and the connection jig 2 are used, the end portions 3c and 3d of the adjacent hollow objects 3a and 3b can be fused at a time. By bonding the end portions 3c and 3d of the adjacent hollow objects 3a and 3b at a time, a desired bonding strength can be obtained more easily.

The thrust (surface pressure) and the ultrasonic oscillation time applied to compress and deform the hollow object when compressing and deforming the ends of the hollow object are the types of the ultrasonic horn, What is necessary is just to select suitably according to the kind of hollow thing, desired joining strength, and a softness | flexibility.
Further, the maximum output and the oscillation frequency in the ultrasonic welder for performing ultrasonic fusion are not particularly limited as long as fusion is possible, but the maximum output is 30 to 2500 W, and the oscillation frequency is 60 kHz to 15. What is necessary is just to select suitably the commercially available welder used as the range of about 15 kHz according to joining conditions.
Any method may be used for the thrust (surface pressure) applied to compress and deform the hollow object as long as a desired thrust can be applied. For example, a weight, a spring, a method using human power, a method using air pressure, hydraulic pressure, and the like can be given. Among them, in an air cylinder using air pressure, the power source is air, and a commercially available compressor or the like can be used to adjust to a desired pressure using a regulator and can be easily supplied. The air cylinder can be used suitably because it can easily change the thrust by changing the supply pressure and can cope with various conditions. In this case, the thrust can be obtained by the product of the cross-sectional area obtained from the air cylinder diameter and the air cylinder supply pressure.
For example, using an ultrasonic welder with a maximum output of 300 W and an oscillation frequency of 28.5 kHz and an air cylinder with a diameter of 32 mm, a hollow braid (polyethylene terephthalate, 830 dtex-96 fil × 16 shots) with an outer diameter of 2.5 mm and an inner diameter of 1.2 mm ) When joining 2.5 to 30 mm in parallel, the oscillation time is about 0.4 to 2 seconds, the thrust is about 50 to 400 N (the air cylinder supply pressure is about 0.06 MPa to 0.51 MPa) It is preferable that

As described above, in the manufacturing method of the present manufacturing example, the end portions of a pair of adjacent hollow objects are not partial, but the entire end portion is compressed and deformed so that the end portions overlap each other. It is possible to prevent problems such as insufficient bonding strength and an increase in diameter of the bonded portion of the shaped article, and to prevent a step from occurring on the side surface of the resulting hollow continuous body. This is because the space portion of the hollow object is compressed by the ultrasonic fusion treatment and deformed so as to decrease or disappear.
Therefore, the obtained hollow continuous body is in a straight line, and is less likely to be clogged or caught when passing through a portion whose outer diameter is regulated. In addition, since the flexibility is not greatly impaired, the travel of the hollow object is stable, and a decrease in process stability during the production and processing of the hollow fiber membrane is prevented.
Moreover, according to the manufacturing method of the hollow continuous body of the said manufacture example, since joining time can be shortened and heating of an ultrasonic horn, a connection jig, etc. is unnecessary, the fusion | melting with respect to these is prevented. In addition, since ultrasonic fusion is performed, bonding can be performed under the same conditions regardless of whether the hollow material is in a dry or wet state. Therefore, a hollow continuous body can be produced efficiently.

The hollow continuous body obtained by the above production method can be suitably used as a support for use in producing a hollow fiber membrane.
As a specific method for producing a hollow fiber membrane using a hollow continuous body as a support, a hollow continuous body is fed out from the center hole of the annular nozzle, and the annular nozzle is disposed on the outer periphery of the hollow continuous body. There is a method in which a membrane-forming stock solution spun from the outer periphery is applied and solidified to form a continuous hollow fiber membrane and then cut.

  In addition, after compression deformation, the cross-sectional shape of the portion where the ends of the pair of hollow objects overlap each other is made into a substantially circular shape. (For example, an ellipse, a triangle, a quadrangle, etc.) may be used.

  Furthermore, in this invention, the edge part of a pair of adjacent hollow thing may be divided | segmented into several, and you may finally make the whole fuse | melt. However, in that case, the fusion part may thermally shrink while the non-fusion part expands, which may impair the running stability of the resulting hollow continuous body. Further, since the subsequent fusion treatment acts on the end portion subjected to the fusion treatment first and overmelts, the desired bonding strength may not be obtained. For these reasons, it is preferable to fuse the entire ends of a pair of adjacent hollow objects at one time as in the above embodiment.

Hereinafter, the present invention will be described in more detail based on examples.
In joining the hollow objects, a connection jig 2 and an ultrasonic welder including the ultrasonic horn 1 as shown in FIGS. 1 and 2 were used.
[Connection jig]
A U-shaped groove 2a having a depth C of 6.1 mm formed linearly was used.
[Ultrasonic welder]
A SONEPET 302S-GM (maximum output 300 W, oscillation frequency 28.5 kHz) manufactured by Seidensha Electronics Co., Ltd. was used.
The ultrasonic horn 1 has a tip width E of 2.2 mm and a length D of 40 mm, and a groove recessed in an arc along the length direction is formed on the lower surface 1a as a pressing surface, and moves vertically in the vertical direction. We used what to do. Moreover, the ultrasonic horn 1 was installed so that the tip could enter the groove 2 a of the connection jig 2.
A low speed air cylinder was used as the power for the vertical movement of the ultrasonic horn 1. This air cylinder is supplied with air whose pressure is adjusted by a pressure reducing valve and whose exhaust speed is adjusted by a speed controller for low speed.
A stopper was provided so that the tip of the ultrasonic horn 1 stopped immediately before the bottom surface of the groove 2 a of the connection jig 2 to prevent contact between the tip of the ultrasonic horn 1 and the bottom surface of the groove 2 a of the connection jig 2.

(Examples 1-18)
The hollow body (A) 3a and the hollow body (B) 3b having the combinations shown in Tables 1 to 3 were joined to obtain a continuous body of hollow bodies.
Specifically, the end 3c of the hollow object (A) 3a is inserted into the groove 2a of the connecting jig 2, and then the end 3d of the hollow object (B) 3b is arranged in parallel as shown in Tables 1 to 3. Inserted in parallel with length A. Next, the ultrasonic horn 1 is lowered by supplying air to the air cylinder under the conditions shown in Tables 1 to 3, and thrust (surface pressure) is applied to the hollow object (A) 3a and the hollow object (B) 3b. It was.
Then, the end portions 3c and 3d of the adjacent hollow object (A) 3a and hollow object (B) 3b are compressed and deformed so that the end portions 3c and 3d overlap each other (see FIG. 4), Ultrasonic waves were oscillated in the state. As a result, the hollow article (A) 3a and the hollow article (B) 3b were joined by ultrasonic fusion to obtain a hollow continuous body. In Example 18, a syringe needle capable of supplying water is inserted into the hollow part from the end of each of the same hollow objects (A) and (B) as in Example 16, and water is put into the hollow part with a pressurized pressure of 200 KPa. Was supplied until water came out from the outer surface of the end of the hollow object to make the hollow object wet.

The joint strength of the joint part of the obtained hollow continuous body was measured as follows using a digital force gauge (ZP-500N) manufactured by Imada Corporation.
First, a ring that can be hooked at both ends of the hollow continuous body was made, one ring was hung on a fixed hook, and the other ring was hung on a hook of a digital force gauge. Next, the digital force gauge was moved so that the pulling direction of the digital force gauge was substantially vertical or horizontal, and the digital force gauge was turned on with no tensile tension applied to the hollow continuous body, and the display value was reset to zero. And it pulled manually and the breaking load was measured using the peak hold function. The breaking load was measured twice, and the average value was obtained. The measurement results are shown in Tables 1-3.

In any of Examples 1 to 18, the breaking load at the joint portion of the obtained hollow continuous body was sufficiently high. Moreover, the cross-sectional shape of the joined portion was substantially the same as the cross-sectional shape of the hollow object before compression deformation. Therefore, when the hollow continuum obtained in Examples 1 to 11 was passed through the center hole of the annular nozzle, it passed smoothly without being caught at the joining portion. Moreover, when the hollow continuous body obtained in Examples 12 to 18 was passed through the hollow fiber membrane production process, it passed smoothly without being caught at the joining portion, as in Examples 1 to 11. Therefore, a decrease in process stability in the production of hollow fiber membranes was prevented.
Further, by comparing Example 16 and Example 18, it was found that sufficient bonding strength was exhibited regardless of whether the hollow object to be bonded was dry or wet.

  The manufacturing method of the present invention prevents problems such as insufficient bonding strength and increased diameter of the bonded portion of the hollow material, and prevents deterioration in process stability during hollow fiber membrane manufacturing and processing without greatly impairing flexibility. It is useful for producing a hollow continuous body.

DESCRIPTION OF SYMBOLS 1 Ultrasonic horn 1a Bottom surface 2 Connection jig 2a Groove 3a, 3b Hollow object 3c, 3d End A Parallel length B Groove width C Groove depth D Ultrasonic horn length E Ultrasonic horn width d1 Outside hollow object Diameter d2 Hollow internal diameter

Claims (7)

A pair of hollow material, after the ends have been arranged so positioned to contact the outer peripheral surface of each other, or the respective ends in contact with the outer peripheral surface of said end portion to one of the connecting members, A method for producing a hollow continuous body in which the entire end portion is compressed and deformed and then joined.   The manufacturing method of the hollow continuous body of Claim 1 which joins an edge part by melt | fusion.   The manufacturing method of the hollow continuous body of Claim 2 which joins an edge part by ultrasonic fusion.   The method for producing a hollow continuous body according to claim 1, wherein the length of the joined portions in the yarn length direction is 150 mm or less.   The method for producing a hollow continuous body according to claim 1, wherein the hollow article is at least one selected from braided string, braided string, and hollow fiber membrane.   The method for producing a hollow continuous body according to claim 1, wherein the connecting member is hollow.   The method for producing a hollow continuous body according to claim 6, wherein the connecting member is made of the same material as that of the hollow body.

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