JPH0330414B2 - - Google Patents

Description

BACKGROUND OF THE INVENTION (Technical Field) The present invention relates to a method for manufacturing hollow fibers for dialysis. More specifically, the present invention relates to a method for producing hollow fibers for dialysis that have little shrinkage during steam sterilization. (Prior Art) Artificial kidney devices that utilize osmotic action, ultrafiltration action, etc. have recently made remarkable progress and are widely used in the medical world. Therefore, in such an artificial kidney device, the extremely thin hollow fiber for dialysis is the most important component. Such hollow fibers are extruded into the air through a spinning dope made of a cellulose solution such as a copper alumonia cellulose solution or a synthetic fiber solution and an annular spinning hole, allowed to fall under their own weight, and then spun into a linear shape. A non-coagulable liquid for the spinning dope is filled and discharged into the center of the spinning dope, and then filled and expanded by falling under its own weight.
It is produced by immersing it in an acid or alkaline solution to coagulate and regenerate it, then washing it, and if necessary, treating it with glycerin, and then drying it. After cutting such hollow fibers to a predetermined length, the bundle is inserted into the cylindrical body of the artificial kidney, and both are fixed with potting material to form a partition, and headers are placed on both outsides of the partition. By attaching it, an artificial kidney is formed. However, since such an artificial kidney contracts when steam sterilized in an autoclave, the hollow fibers inserted relatively loosely within the cylindrical body become taut due to the contraction. become. Therefore, the space between the inner surface of the cylindrical body and the hollow fiber bundle and between each hollow fiber becomes wide, so that when performing dialysis using the artificial kidney, the dialysate can sufficiently contact the hollow fibers. There is a risk that the membrane may pass through the membrane without causing any damage, and this has the disadvantage that a sufficient dialysis effect cannot be obtained. OBJECT OF THE INVENTION Therefore, an object of the present invention is to provide a novel method for producing hollow fibers for dialysis. Another object of the present invention is to provide a method for producing hollow fibers for dialysis that exhibit less shrinkage during steam sterilization. Still another object of the present invention is to provide a method for producing hollow fibers for dialysis with excellent water removal ability. These objectives are to discharge cellulose-based spinning dope through an annular spinning hole, simultaneously introduce and fill the center of the interior with a non-coagulable liquid, pass through the coagulable liquid to solidify and regenerate, and then wash with water. The hollow fibers obtained at 95-110℃ and 0-0.4
Production of a hollow fiber for dialysis, which comprises a step of contacting with water vapor for 1 to 4 seconds under a pressure of Kg/cm ² (gauge pressure), a step of plasticizing treatment, and further drying. This is accomplished by a method. Further, the present invention provides that the hollow fibers do not come into contact with water vapor.
This is a method for producing hollow fibers for dialysis, which is carried out for 2 to 4 seconds at 100 to 110° C. and a pressure of 0 to 0.4 Kg/cm ² (gauge pressure). Further, the present invention is a method for producing hollow fibers for dialysis, in which the cellulose-based spinning dope is a copper ammonia cellulose solution. DETAILED DESCRIPTION OF THE INVENTION Hollow fibers produced according to the present invention include cellulose fibers such as cuprammonium cellulose and cellulose acetate, particularly cuprammonium cellulose. Various types of cellulose can be used, but to give an example, for example, average degree of polymerization
500 to 2500 is preferably used. Thus, the cuprammonium cellulose solution is prepared by a conventional method. For example, first, aqueous ammonia, a basic aqueous copper sulfate solution, and water are mixed to prepare an aqueous cupric ammonia solution, an antioxidant (e.g., sodium sulfite) is added to this, then the raw material cellulose is added and dissolved with stirring, and then An aqueous sodium hydroxide solution is added to completely dissolve undissolved cellulose to obtain a cuprammonium cellulose solution. This cuprammonium cellulose solution may further be mixed with a permeability control agent for coordination bonding. There are various spinning methods, such as the aerial drop method, Japanese Patent Application Laid-Open Nos. 57-71408 and 57-
The method of discharging into a non-coagulable liquid and then passing through the interface between the non-coagulable liquid layer and the coagulating liquid as described in No. 71410, and the method of discharging directly into a non-coagulable liquid as described in JP-A-57-71409. Thereafter, a method of passing through a coagulable liquid, a method of surrounding the non-coagulable liquid and discharging it as described in JP-A No. 57-71411, and then coagulating and regenerating it, and a method of coagulating the liquid as described in JP-A-57-199808. A liquid is directly discharged from an annular spinning hole into the non-coagulable liquid of a solution in which the upper layer is filled with a non-coagulable liquid made of a halogenated hydrocarbon and the lower layer is filled, and at the same time, the non-coagulable liquid is introduced and filled into the central part of the inside. There are methods of solidifying and regenerating the material by passing it through a coagulable liquid (hereinafter referred to as flotation method), etc.
Since the latter levitation method is particularly preferred, the present invention will be described below by taking this as an example and referring to the drawings. FIG. 1 is a side view schematically showing an entire apparatus for producing hollow fibers using the method and apparatus according to the present invention. That is, in a bathtub 2 provided with a non-coagulable liquid tank 1 at the bottom, the non-coagulable liquid tank 1
and a non-coagulable liquid 3 comprising a halogenated hydrocarbon as a lower layer and relative to the cellulose-based spinning stock solution.
Further, as an upper layer, a coagulable liquid 4 having a smaller specific gravity than the non-coagulable liquid and relative to the spinning stock solution is supplied to form two layers in the bathtub 2. The spinning stock solution in a stock solution storage tank (not shown) is pumped through a conduit 5 and is directly pushed into the lower non-coagulable liquid 3 through an annular spinning hole (not shown) provided upward in a spinneret device 6. put out. At that time, a non-coagulable liquid for the spinning dope stored in an internal liquid storage tank (not shown) is supplied as an internal liquid to the spinneret device through a conduit 7, and the linear spinning dope is extruded into an annular shape. 8 and discharged. The linear spinning dope 8 extruded from the annular spinning hole advances upward in the non-coagulable liquid 3 in the lower layer without coagulating at all while containing the non-coagulable liquid inside. In this case, the linear spinning dope 8 rises while receiving buoyancy due to the difference in specific gravity with the non-coagulable liquid. Then, this linear spinning stock solution 8 rises into the coagulable liquid 4 in the upper layer, so it is changed in direction by a direction changing rod 9 provided in the coagulable liquid 4 and sufficiently passed through the coagulable liquid 4. After letting
It is pulled up by roll 10. Further, while the coagulated and regenerated hollow fibers pulled up by the drive roll 11 are conveyed by the conveying device 12, an alkali cleaning device 13, a first water washing device 14, an acid cleaning device 15, and a second water washing device are installed on the conveying device 12. 1
Shower cleaning is performed in step 6, followed by re-solidification, water washing, decopper removal, and water washing. The hollow fibers thus cleaned are then introduced into a steam treatment device 18 and treated by contacting them with steam,
After being treated with glycerin in the plasticizing treatment tank 17 if necessary, it is further introduced into the drying device 19 and dried. The steam treatment can be carried out in various ways, but for example, as shown in Figure 2,
A cylindrical body 2 with end plates 20a and 20b at both ends.
1 inside partition walls 22a, 22b, 22c, 22d, 2
A plurality of steam treatment chambers 23a, 23b, 23c, 23d, 23e, 2 partitioned by 2e and 22f.
3f and 23g, and a steam inlet 24 is provided in at least one of the steam treatment chambers, for example, a substantially central steam treatment chamber, and the end plate 20
a, 20b, and partition walls 22a, 22b... with a central fiber passage hole 24.
The hollow fibers are passed through the central fiber passage hole 25 in the center, and water vapor is introduced from the water vapor introduction port 24 and brought into contact with the hollow fibers. The steam introduced into the steam treatment chamber 23d comes into contact with the hollow fibers 8 running inside the steam treatment chamber 23d, and then enters the adjacent steam treatment chambers 23c and 23e through the hollow fiber passage holes 24, and the hollow fibers 8 and The fibers contact the hollow fibers 8, and then successively enter adjacent steam treatment chambers in the same manner to repeat the contact with the hollow fibers 8. Finally, after being subjected to contact treatment in the steam treatment chamber at the end, it is discharged from the steam outlet 26 or the hollow fiber passage hole 25. Note that each steam treatment chamber is provided with a drain (not shown) if necessary. Further, the outside of the cylindrical main body 21 is provided with heat insulation if necessary. Therefore, as water vapor, 0 to 0.4 Kg/cm (gauge pressure) at 95 to 110°C, preferably 100 to 110°C.
is used, and the contact time with the hollow fiber is from 1 to
4 seconds, preferably 2 to 4 seconds. The glycerin treatment is carried out by immersing the hollow fibers 8 in an aqueous glycerin solution stored in the plasticizing chamber 17 and running them, then pulling them up with rollers and sending them to the drying device 19. The concentration of this glycerin aqueous solution is usually 0.5 to 5% by weight.
Preferably it is 1 to 4.5% by weight. In addition, the temperature of the glycerin aqueous solution is 20 to 60℃, preferably 40 to 60℃.
It is ℃. Of course, this plasticizing step using glycerin treatment may be provided before the steam treatment step. Note that drying is performed by a conventional method. Next, the method of the present invention will be explained in more detail with reference to Examples. Example 1 Add basic copper sulfate to 2354 g of 25% ammonia aqueous solution.
Prepare a copper ammonia aqueous solution by suspending 540g,
To this was added 1690 g of a 10% aqueous sodium sulfite solution. To this solution, 2273 g of wet-pulverized Kotton linter pulp with a degree of polymerization of about 1000 (±100) and dehydrated water-containing linter (water content 69.7%) was added, and 210 g of RO water for concentration adjustment was added and dissolved with stirring. ,
Next, 1233 g of 10% sodium hydroxide aqueous solution was added to make a copper ammonia cellulose aqueous solution (specific gravity
1.08) was prepared and used as a spinning stock solution. On the other hand, using a device as shown in FIG.
1,1-trichloroethane was fed to form a lower layer, and then an aqueous sodium hydroxide solution with a concentration of 50 g/ml was fed as a coagulating liquid to form an upper layer. The spinning dope is introduced into a spinneret device ⁶ equipped with an annular spinning hole facing upward, and a non-coagulating liquid 3 with a liquid temperature of 20±2° C.
It was discharged directly into the interior. The diameter of the spinning hole was 3.8 mm, and the discharge rate of the spinning stock solution (cell 7.8%, 1.100 p (20°C)) was 5.86 ml/min. On the other hand, isopropyl myristate (specific gravity 0.854) was introduced from the non-coagulable liquid introduction pipe 7 attached to the spinneret device 6, and was included in the linear discharge stock solution and discharged. The diameter of the introduction tube was 1.2 mm, and the discharge rate of isopropyl myristate was 1.50 ml/min. Next, the discharge stock solution (containing non-coagulable liquid) 8 (specific gravity 1.026) was heated 1, 1,
After rising in 1-trichloroethane and further rising in the upper layer of an aqueous sodium hydroxide solution (20±2°C), it was moved in a horizontal direction using a deflection rod 9. The layer height of the non-coagulable liquid at this time is 200 mm,
The distance from the interface to the upper end of the deflection rod 9 is 150 mm,
The spinning speed was 60 m/min, the traverse width was 80, and the running distance was 4.4 m. After being pulled up from this bath by rollers 10, it is deposited on a conveying device 12, and on the conveying device 12, a 12% aqueous sodium hydroxide solution is sprinkled in a shower to fully solidify, washed with water, and regenerated with 5% sulfuric acid ( Copper removal treatment)
After further washing with water, it was subjected to steam treatment. The steam treatment was carried out by introducing steam at 110° C. (0.4 Kg/cm ² ·G) from the steam inlet 24 as shown in FIG. 2, and bringing it into contact with the hollow fibers for 2.5 seconds.
Next, the hollow fibers treated with water vapor in this way were placed in a 1.5% by weight glycerin aqueous solution (liquid temperature 20°C).
Plasticization treatment was performed by immersing the material in water for 20 minutes. Further, the hollow fibers were dried with hot air at a temperature of 80° C. for 39 seconds to obtain hollow fibers for dialysis. Regarding the hollow fiber for dialysis thus obtained, the shrinkage rate, UFR and middle molecule removal ability after steam sterilization were measured and the results were as shown in Table 1. Examples 2 to 4 Hollow fibers for dialysis were constructed in the same manner as in Example 1, except that the steam treatment conditions were varied as shown in Table 1, and the same tests were conducted. However, the results shown in Table 1 were obtained. Comparative Example Hollow fibers for dialysis were produced in the same manner as in Example 1, except that the steam treatment was omitted, and the same tests were conducted, and the results shown in Table 1 were obtained. Comparative Examples 2 to 7 Hollow fibers for dialysis were produced in the same manner as in Example 1, except that the water vapor treatment conditions were varied as shown in Table 1, and the same tests were conducted. , the results shown in Table 1 were obtained.

【table】

[Table] Specific Effects of the Invention As described above, the present invention discharges a cellulose-based spinning stock solution from an annular spinning hole, simultaneously introduces and fills a non-coagulable liquid into the center of the interior, and then drains the coagulable liquid. After being coagulated and regenerated by passing through the fibers, the hollow fibers thus obtained are washed with water at a temperature of 95 to 110°C and a pressure of 0 to 0.4 Kg/cm ² (gauge pressure).
Since this is a method for producing hollow fibers for dialysis, which includes a step of contacting with water vapor for 4 seconds, a step of plasticizing treatment, and further drying, artificial kidneys etc. using the hollow fibers can be produced. When sterilized with steam, the shrinkage is very small, so even though both ends are fixed with a potting agent, it remains relatively loose within the cylindrical body of the artificial kidney. Therefore, the gaps between the inner surface of the cylindrical body and the hollow fiber bundle and between the hollow fibers are relatively small, so that when performing dialysis using the artificial kidney, the dialysate is in sufficient contact with the hollow fibers. Therefore, a sufficient dialysis effect can be obtained. It also has the advantage of having a high ability to remove UFR and middle molecules. In addition, steam treatment is carried out at 100 to 110℃ for 0 to 0.4 kg/
The above effect is further enhanced by carrying out the test at cm ² ·G for 2 to 4 seconds. Furthermore, particularly excellent effects are exhibited when cuprammonium cellulose is used as the cellulose.

[Brief explanation of drawings]

FIG. 1 is a side view schematically showing the entire apparatus used in the method of the present invention, and FIG. 2 is a partially cutaway perspective view schematically showing the steam treatment apparatus used in the method of the present invention. 6...All spinneret equipment, 8...Linear spinning dope, 1
2... Conveyance device, 14, 16... Water washing device, 17
...Plasticization treatment tank, 18 ...Steam treatment device, 1
9...Drying device.

Claims (1)

[Scope of Claims] 1. A cellulose-based spinning dope is discharged from an annular spinning hole, a non-coagulable liquid is introduced and filled into the center of the interior at the same time, and then passed through a coagulable liquid to be solidified and regenerated, and then washed with water. The hollow fibers obtained in this way are
A process of contacting with water vapor for 1 to 4 seconds at a temperature of 95 to 110°C and a pressure of 0 to 0.4 Kg/cm ² (gauge pressure), and a process of plasticizing treatment, and further drying. A method for producing hollow fibers for dialysis, characterized by: 2. The contact between the hollow fiber and water vapor is carried out for 2 to 4 seconds at a temperature of 95 to 110°C and a pressure of 0 to 0.4 Kg/cm ² (gauge pressure).
The method for producing hollow fibers for dialysis as described in 2. 3. Claim 1 or 2, wherein the cellulose-based spinning dope is a copper ammonia cellulose solution.
The method for producing hollow fibers for dialysis as described in 2.