JPH07252721A - Production of hollow fiber for dialysis - Google Patents

Abstract

PURPOSE:To provide a process for producing a hollow fiber having sufficient performance as a hollow fiber for dialysis without using fluorocarbons in a process having a step to remove the non-coagulating liquid filled in a hollow fiber in the spinning process. CONSTITUTION:A spinning dope is extruded in the form of a tube while extruding a non-coagulating liquid into the hollow part of the tube. The non- coagulating liquid is free from coagulating action to the spinning dope and has an ignition point of 30-95 deg.C, a boiling point of 105-240 deg.C and a vapor pressure of 0.8-60Torr at 60 deg.C. The extruded spinning dope is coagulated or regenerated and the obtained hollow fiber is cut and blown to remove the non- coagulating liquid from the hollow fiber for dialysis.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a hollow fiber for dialysis. In particular, it relates to a method for producing a dialysis hollow fiber used as a dialysis membrane of an artificial dialyzer.

[0002]

2. Description of the Related Art Conventionally, in a method for producing a hollow fiber for dialysis, a spinning stock solution extruding step for simultaneously extruding a spinning stock solution and a non-coagulating liquid filled therein, a coagulating step, a regenerating step, a washing step, and a winding step. It is manufactured continuously. Then, the wound hollow fiber is cut into a predetermined length, and then a non-coagulating liquid removing step for removing the non-coagulating liquid inside is performed.

Then, in the step of removing the non-coagulable liquid,
It is necessary to remove the non-coagulating liquid, which is an organic solvent introduced into the hollow fiber in a core form, without leaving it.
For this purpose, the non-coagulable liquid has been removed by washing with a detergent. And as a cleaning agent, it is soluble in non-coagulable liquid, does not deteriorate the performance of the hollow fiber, is easy to dry and does not easily remain, and has high biological safety. However, chlorofluorocarbons (for example, CFC 113) and mixtures thereof have been used because they satisfy these requirements, and are nonflammable and easy to handle (Japanese Patent Publication No. 56-22541).
Issue).

[0004]

However, in recent years, it has been pointed out that the ozone layer of CFCs is depleted, and it is required not to use CFCs in order to protect the global environment. Therefore, we conducted diligent research on a cleaning agent that can replace CFCs, but could not find a suitable one. However, on the contrary, if the non-coagulable liquid can be removed without performing the above-described cleaning step using chlorofluorocarbon, the present inventors eventually use chlorofluorocarbon (fluorocarbon). It has been found that the method for producing a hollow fiber including the step of removing the non-coagulable liquid can be achieved without any problem.

Therefore, an object of the present invention is to provide a method for producing a dialysis hollow fiber which includes a step of removing a non-coagulable liquid filled in the hollow fiber in a spinning step, without using CFC and in a dialysis hollow fiber. It is intended to provide a method for producing a hollow fiber for dialysis, which is capable of producing a hollow fiber having sufficient performance as a thread.

[0006]

[Means for Solving the Problems] What achieves the above-mentioned object is to extrude a spinning dope into a tubular shape and at the same time show a non-coagulating property with respect to the spinning dope and have a flash point of 30 ° C to 95 ° C.
C., boiling point is 105.degree. C. to 240.degree. C., steam pressure at 60.degree. C. is 0.8-60 torr. It is a method for producing a hollow fiber for dialysis, which comprises cutting the regenerated hollow fiber and then removing the non-coagulable liquid inside the hollow fiber by blowing air.

Further, the object to achieve the above-mentioned object is to extrude the spinning dope into a tubular shape and at the same time exhibit non-coagulation properties with respect to the spinning dope, and have a flash point of 30 ° C to 95 ° C and a boiling point of 105 ° C to 240 ° C. , The vapor pressure at 60 ° C is 0.8 to
Inject and fill 60 torr non-coagulant liquid,
Coagulate the extruded spinning solution through a coagulating liquid,
After regeneration, alkali treatment with an alkaline aqueous solution, followed by acid treatment, plasticization treatment, and further cutting of the dried hollow fiber, followed by blowing, the non-coagulation inside the hollow fiber. This is a method for producing a hollow fiber for dialysis that removes a sexual fluid.

The non-coagulating liquid is preferably a hydrocarbon having 9 or more carbon atoms. The non-coagulable liquid is
It is preferably a hydrocarbon having 9 to 14 carbon atoms. The non-coagulating liquid may be a mixture of two or more kinds of hydrocarbons having 9 or more carbon atoms. The non-coagulable liquid has 9 to 1 carbon atoms.
It may be a mixture of two or more of the hydrocarbons of No. 4 above. The non-coagulating liquid preferably has a flash point of 70 ° C. or higher. Further, the non-coagulating liquid is preferably a third petroleum.

It is preferable that the step of removing the non-coagulable liquid inside the hollow fiber by blowing air is performed by blowing heated air into the hollow fiber.
The step of removing the non-coagulable liquid inside the hollow fiber by blowing air is preferably performed by blowing air whose humidity has been adjusted (humidified air) into the hollow fiber. In addition, the step of removing the non-coagulating liquid inside the hollow fiber by blowing air is
It is preferable that the heating and the humidity are controlled (heated / humidified air) to be blown into the hollow fiber. The temperature of the heated air is 50 to 120.
C is preferred. The humidity of the humidified air is 20 to 20.
It is preferably 100% (relative humidity).

【Example】

Then, the method for producing the hollow fiber for dialysis of the present invention will be explained using the production apparatus shown in FIG. The examples of the production method of the present invention will be outlined. The spinning dope is extruded into a tubular shape, and at the same time, the spinning dope is non-coagulable and has a flash point of 30 ° C to 95 ° C and a boiling point of 105 ° C to 240 ° C.
A spinning stock solution discharge step of introducing and filling a non-coagulating solution having a vapor pressure of 0.8 to 60 Torr at 60 ° C. and 60 ° C., and a coagulation / regeneration step of passing the extruded spinning stock solution through the coagulating solution , A re-coagulation step of treating with an alkaline aqueous solution, a washing step of washing with water, an acid treatment step of treating with an acid aqueous solution (copper removal treatment step), a re-rinsing step, a plasticizing treatment step, and a drying step, And a winding step of winding the dried hollow fiber. The steps up to this point can be performed continuously. Furthermore, the method for producing a hollow fiber of the present invention comprises a cutting step of cutting the hollow fiber wound around a bobbin or the like into a predetermined length, a bundle forming step of bundling the cut hollow fibers into a bundle, and a bundle shape. It has a non-coagulating liquid removing step of removing the non-coagulating liquid inside the hollow fibers by blowing air (sending gas) into the bundled hollow fibers.

Therefore, each step will be described. The hollow fiber produced by the present invention includes cellulose fibers such as cuprammonium cellulose and cellulose acetate, and cuprammonium cellulose is particularly preferable. Although various types of cellulose can be used, those having an average degree of polymerization of about 500 to 2500 are preferable. The cellulose concentration in the spinning dope is 5.5 to 8.
It is preferably 7%, particularly preferably 7.0-8.5%, and the spinning solution has a viscosity of 250-1,300 poise (2
0 ° C.) is preferable, and 800 to 1,200 is particularly preferable.
It's a poise.

When the cellulose concentration of the spinning dope is lower than 5.5%, the hollow fiber obtained may have many pinholes and may have low mechanical strength. Further, when the cellulose concentration is higher than 8.7%, the strength of the hollow fiber increases, but on the other hand, the viscosity increases, which makes it difficult to handle and causes pulsation during spinning.
In some cases, it may be difficult to obtain the desired pore size, open area ratio and dialysis ability due to the difficulty of spinning due to cutting.

If the spinning dope is, for example, a copper ammonia cellulose spinning dope, basic copper sulfate is suspended in an ammonia solution to prepare a copper ammonia solution,
An aqueous solution of sodium sulfite was added to this, and a cotton linter pulp having a degree of polymerization of about 1,000 (± 100) was wet-milled into this solution, and dehydrated hydrous linter was added to the mixture to add water for concentration adjustment, and stirring and dissolution were performed. Then, it is prepared by adding an aqueous solution of sodium hydroxide to prepare an aqueous solution of copper ammonia cellulose. Then, in the spinning stock solution discharging step, as the non-coagulating liquid discharged together with the spinning stock solution, and in a state of being filled in the inside thereof in a core shape,
It shows non-coagulation properties for the spinning dope and has a flash point of 30.
C. to 95.degree. C., a boiling point of 105.degree. C. to 240.degree. C., and a vapor pressure at 60.degree. By using such a non-coagulable liquid, the step of removing the non-coagulable liquid described below can be performed by blowing air,
It can be removed without using CFCs.

When the non-coagulating liquid is specifically described, for example, a hydrocarbon having 9 or more carbon atoms is suitable. Further, it is more preferable that the hydrocarbon is 9 to 14. If the hydrocarbon is a 9th or higher hydrocarbon, its flash point and boiling point are not so low, and if it has 14 or less carbon atoms, it has sufficient volatility and is easily removed. As the hydrocarbon, a saturated hydrocarbon is preferable from the viewpoint of stability. The hydrocarbon preferably has a straight chain, but may have a side chain or may be cyclic. Further, it is preferable that the flash point is 70 ° C. or higher from the viewpoint of safety during use. Similarly, a boiling point of 130 ° C. or higher is also suitable from the viewpoint of safety during use. Further, it is preferable that the vapor pressure is 5 to 20 Torr from the viewpoints of reliable removal and shortened removal time.

Specific examples of the non-coagulating liquid include C ₉ H
₂₀ [Nonane (preferably n-nonane, flash point 31 ° C.,
Boiling point 149.5 ° C, vapor pressure 20 torr, density 0.71
8)], C ₁₀ H ₂₂ [decane (preferably n-decane,
Flash point 53 ° C, boiling point 169 to 173 ° C, vapor pressure 10 torr, density 0.734 (15 ° C)], C ₁₁ H ₂₄ [undecane (preferably n-undecane, flash point 68 ° C, boiling point 189 to 194 ° C). , Vapor pressure 7 torr, density 0.744
(15 ° C.)], C ₁₂ H ₂₆ [dodecane (preferably n-
Dodecane, flash point 87 ° C, boiling point 214.5 ° C, vapor pressure 4
Tor, density 0.751)], C ₁₃ H ₂₈ [tridecane (preferably n-tridecane, flash point 99 ° C., boiling point 2
27 ° C, vapor pressure 2 torr, density 0.760)], C ₁₄ H
₃₀ [tetradecane (preferably n-tetradecane, boiling point 253 ° C., vapor pressure 0.7 torr, density 0.765)]
Is. Particularly preferred among the above hydrocarbons are nonane, decane, undecane and dodecane.

Further, the non-coagulable liquid may be a simple substance of the above-mentioned hydrocarbon, but may be a mixture of two or more kinds of the above-mentioned hydrocarbon. For example, the above-mentioned mixture of undecane and dodecane may be used. As the mixture, undecane: dodecane = 4-1: 1: 3-2 is suitable, and specifically, undecane: dodecane = 4: 1 [flash point 70 ° C., boiling point 189-211 ° C., vapor pressure 6 0.6 torr, density 0.745 (15 ° C.), tertiary petroleum] are preferred. Furthermore, the non-coagulable liquid is preferably a third petroleum. If it is a third petroleum, it is easy to handle. Also, the non-coagulable liquid is only hydrocarbon,
If necessary, additives such as surfactants and stabilizers may be added.

Further, as the non-coagulable liquid, one that satisfies the above-mentioned conditions and has a lower specific gravity than the coagulable liquid described later is preferable. When the yarn is cut during manufacturing, the non-coagulating liquid does not settle below the coagulating liquid and floats on the surface of the coagulating liquid, so that it can be easily removed. The above-mentioned hydrocarbons can be preferably used because they have a lower specific gravity than the coagulating liquid. Since a sodium hydroxide aqueous solution is usually used as the coagulating liquid, the specific gravity (density) is substantially 1. Therefore, it is preferable to use a non-coagulating liquid having a specific gravity (density) of less than 1. The above hydrocarbons are usually less than 1 (about 0.8).
It has a specific gravity (density) of. Then, the spinning dope and the non-coagulating liquid thus prepared are extruded from the discharging device. There are various spinning methods,
For example, there are the aerial drop method as shown in JP-B-53-30808 and the floating spinning method as shown in JP-A-57-199808.

An embodiment of the air drop method will be described with reference to FIG. The discharge device 2 has a built-in annular nozzle, and extrudes the spinning dope from the spinning dope inlet 7 into a tube shape and the non-coagulating liquid from the non-coagulating liquid inlet 5 into a linear form. The core is filled in the center of the inside. In this way, the linear spinning dope having the non-coagulable liquid filled therein is stretched by free fall in the air, and is introduced into the bath 4 installed immediately below. The bath 4 is filled with a coagulating liquid.

The diameter of the spinning dope discharge port of the discharging device is preferably 1.5 to 5 mm, and the spinning dope discharge amount is preferably 4 to 12 ml / min. Further, the diameter of the discharge port of the non-coagulable liquid is preferably 0.3 to 2 mm, and the discharge amount of the non-coagulable liquid is preferably 1.0 to 4.0 ml / min. The linear velocity ratio at the time of discharging the spinning dope and the non-coagulating liquid was 0.
About 1 to 1.5 is suitable. The distance between the discharge device 2 and the bath 4 is preferably 150 to 450 mm. An alkaline aqueous solution is used as the coagulating liquid. Specifically, the non-coagulable liquid is preferably sodium hydroxide, potassium hydroxide, lithium hydroxide, ammonium hydroxide or the like, but sodium hydroxide is particularly preferable. The alkali concentration is preferably 1.5 to 3.5 N.

Then, the spinning dope that has plunged into the coagulating liquid bath 4 is horizontally changed by the deflecting rod 9 and runs in the bath. The speed of the stock solution for spinning in the bathtub 4 (in other words, the spinning speed is preferably 40 to 180 m / min.
After being pulled up by 11, the carrier 12 is shaken off, and the sodium hydroxide aqueous solution (alkali aqueous solution) is sprinkled on the carrier 12 by the sodium hydroxide aqueous solution spraying device 13 (alkaline aqueous solution spraying device) like a shower. After being solidified, water is sprinkled in a shower shape by the water sprinkling device 14 for washing treatment, and sulfuric acid (5%) is sprinkled in a shower shape by the acid aqueous solution sprinkling device 15 for regeneration treatment (copper removal treatment). Again, the second water sprinkling device 16 sprinkles water in a shower shape to perform a washing process. The hollow fiber 22 thus solidified and regenerated is pulled up from the transport device 12 by the roller 20 and travels in the plasticizing treatment tank 17. A glycerin solution is preferably used as the plasticizing liquid. afterwards,
The hollow fiber is a dryer 1 in which a plurality of rollers are arranged in a zigzag pattern.
After passing through 8 and being dried, it is wound around a bobbin 19.

Next, a step of removing the non-coagulable liquid inside the hollow fiber by blowing air is performed. The hollow fibers wound around the bobbin 19 as described above are cut into a predetermined length and then bundled in a predetermined number to form a hollow fiber bundle. The hollow fiber bundle is formed by bundling with a bundle forming member such as a film. Then, in the state where this hollow fiber bundle is stood, it is put in a blower dryer, and by blowing air from above, the non-coagulable liquid filling the inside of the hollow fiber is discharged, and the hollow fiber inner surface The attached non-coagulating liquid is volatilized and the non-coagulating liquid is removed. In addition, it is preferable that the above-mentioned air blowing is performed from the upper side to the lower side in a state where the hollow fiber bundle is erected, because the discharge efficiency of the non-coagulable liquid is high, but the present invention is not limited to this, and the hollow fiber bundle is laid horizontally. You may go in the state. in any case,
Air may be blown into the hollow fibers. And this ventilation promotes volatilization of the non-coagulating liquid.

The air flow rate is 60 to 250 ml.
/ Min is preferable. If it is 60 ml / min or more, it is preferable in terms of discharge efficiency and promotion of volatilization.
When it is 50 ml / min or less, problems such as blowing pressure and deformation of the hollow fiber do not occur, which is preferable. Further, the blowing time is preferably 20 to 180 minutes. The gas to be blown may be any gas as long as it is inert to the hollow fibers, and air, nitrogen, etc. can be used, but air is preferable because it is easy to handle.

Further, the step of removing the non-coagulable liquid inside the hollow fiber by blowing air is preferably performed by blowing heated air into the hollow fiber. By doing so, since the non-coagulable liquid is also heated, the removal rate of the non-coagulable liquid is high and the removal time (volatilization rate) can be short. And the temperature of the heated air is preferably 50 to 120 ° C. If it is 50 ° C. or higher, the volatilization of the non-coagulating liquid can be promoted, and if it is 120 ° C. or lower, the hollow fiber does not deteriorate.

The step of removing the non-coagulable liquid inside the hollow fiber by blowing air is preferably carried out by blowing air whose humidity has been adjusted (hereinafter, "humidified air") into the hollow fiber. By doing so, it is possible to prevent the hollow fiber from rapidly becoming dry and deteriorated during air blowing. The humidity of the conditioned air is 20 to 20.
It is preferably 100% (relative humidity). When it is 20% or more, the blown hollow fiber is not excessively dried and is not deteriorated, and when it is 100% or less, the surface of the hollow fiber is not watered, which is preferable. Preferably,
40 to 95%, and if it is 40% or more, deterioration of the hollow fiber due to overdrying does not occur, and 95%
When the temperature is below, dew condensation does not occur on the hollow fiber bundle during heating and cooling, which is preferable.

Further, it is preferable that the step of removing the non-coagulable liquid inside the hollow fiber by blowing air is performed by blowing heated and humidified air into the hollow fiber. By doing so, since the non-coagulable liquid is also heated, the removal rate of the non-coagulable liquid can be high, the removal time (volatilization rate) can be short, and the hollow fiber can be It is possible to avoid deterioration due to sudden drying. The preferable temperature and humidity conditions when both the heating and the humidification are performed are as described above.

The dialysis hollow fiber thus produced has an inner diameter of 150 to 300 μm, preferably 1
80-250 μm, wall thickness 8-30 μm, preferably 10-25 μm, ultrafiltration rate 2.5-60 m
1 / mmHg · hr · m ² . Then, the hollow fiber bundle from which the non-coagulable liquid has been removed in this way is housed in a polycarbonate resin housing, both ends are fixed by a polymer potting agent, and blood ports are fixed at both ends of the housing. It becomes an artificial dialyzer.
The artificial dialyzer thus prepared is sterilized by high-pressure steam, ethylene oxide gas, or the like.

Further, in the above description, the air-drop method is used as an example, but the levitation spinning method may be used. In the case of the levitation spinning method, for example, an apparatus as shown in FIG. 2 can be used. In the bath 2, the non-coagulating liquid is supplied to the non-coagulating liquid tank to form the non-coagulating liquid layer 3 (lower layer 3), and further on the non-coagulating liquid layer 3, the coagulating liquid layer 4 is formed.
By providing the (upper layer 4), a two-layer liquid structure in which the lower layer is the non-coagulating liquid layer and the upper layer is the coagulating liquid layer is formed in the bath 2. As the coagulating liquid, the above-mentioned ones can be used, and as the non-coagulating liquid, the halogenated hydrocarbon has a specific gravity of 1.3 or more, preferably 1.4 to 1.7. Solubility is 0.15g / 100
It is less than or equal to ml, preferably less than or equal to 0.05 g / 100 ml. For example, carbon tetrachloride, 1,1,1,
-Trichloroethane, 1,1,2-trichloroethane,
Examples include trichloroethylene, tetrachloroethane, tetrachloroethylene and the like. As the coagulating liquid, an alkaline aqueous solution is used, and examples thereof include sodium hydroxide, potassium hydroxide, lithium hydroxide, ammonium hydroxide, and the like, but sodium hydroxide is preferable. The alkali concentration is 1.5 to 3.5 normal.

A discharge device 6 (spinneret device 6) is attached to the lower part of the non-coagulating liquid tank of the bath 2 (the lower part of the non-coagulating liquid layer 3) so that the annular spinning port faces upward. ing. A spinning stock solution introducing pipe 7 and a non-coagulating liquid introducing pipe 5 are connected to the discharge device 6. Then, the spinning stock solution and the non-coagulating liquid filled therein are directly discharged from the spinneret of the spinneret device 6 into the lower non-coagulating liquid layer 3. The discharged spinning stock solution (containing the non-coagulating liquid) rises in the non-coagulating liquid layer 3, further rises in the coagulating liquid layer 4 of the upper layer 4, and then is deflected horizontally by the deflecting rod 9. After that, the rollers 10 and 11 are pulled up from the bath 4 as in the embodiment shown in FIG. Regarding the other points, the same thing and method as those of the above-mentioned embodiment can be preferably used.

Next, specific examples of the present invention will be described. (Example 1) 250 g of basic copper sulfate was suspended in 1,160 g of 25% aqueous ammonia solution to prepare a copper ammonia aqueous solution, and 830 g of 10% sodium sulfite aqueous solution was prepared.
Was added. Wet-milled cotton linter pulp in this mixed solution and dehydrated water-containing linter (water content 60%) 8
00 g was added, 300 g of RO water for concentration adjustment was added and dissolved by stirring, and then 540 g of a 10% sodium hydroxide aqueous solution was added to prepare a copper ammonia cellulose aqueous solution (specific gravity 1.09) to prepare a spinning stock solution. . The cellulose concentration of this spinning dope was 8.0%, and the viscosity was 1,100 poise (20 ° C.).

On the other hand, an aqueous sodium hydroxide solution having a concentration of 3.5 N was supplied into the bath 2 using the apparatus shown in FIG. The above spinning dope was introduced into the discharging device 6 through the spinning dope inlet 7 and discharged from the spinning hole at a nitrogen pressure of 7 kg / cm ² . The diameter of the discharge port of the discharge device was 4 mm, and the discharge amount of the spinning dope was 8.2 ml / min. On the other hand, a non-solidifying liquid (NS Clean 200, manufactured by Nikko Petrochemical Co., Ltd., undecane: dodecane = 4: 1 mixture from the non-solidifying liquid inlet 5 of the discharge device [flash point 70 ° C., boiling point 189-21
1 ℃, vapor pressure 6.6 Torr, density 0.745 (15 ℃)
[3rd petroleum] was introduced and encapsulated in the above linear discharge spinning dope and discharged. The diameter of the non-coagulable liquid discharge port is 0.8
mm, and the discharge rate of the non-coagulating liquid was 2.1 ml / min. The linear velocity ratio when discharging the spinning dope and the non-coagulating liquid is 0.2.
Met.

Then, a discharge spinning dope (containing a non-coagulating liquid,
The specific gravity of 1.035) was naturally dropped into the air and made to plunge into the bath 4 (solidifying liquid tank). The height from the spinning stock solution discharge port to the liquid surface of the non-coagulating liquid was 300 mm. Then, the spinning stock solution that has rushed in is diverted in the horizontal direction by the diverting rod 9, and the coagulating liquid [sodium hydroxide aqueous solution (20 ± 2
C.)] was run to solidify. The spinning speed is
The parallel traveling distance was 80 m / min and 4.0 m. After being pulled up from the bathtub 4 by the roller 10, it is shaken off on the carrier and sprinkled with a 10% sodium hydroxide aqueous solution on the carrier to give a sufficient solidification, and then washed with water.
Further, after regenerating treatment (copper removal treatment) with 1.0% sulfuric acid and further washing with water, the hollow fiber was pulled up from the conveying device by a roller and made to run in the plasticizing tank. A 4% glycerin solution was used as the plasticizing liquid. After that, the roller 18 was run in a dryer 18 in which a plurality of rollers are arranged in a staggered manner to dry it, and then wound on a bobbin. In addition, dryer 1
The temperature of the contact portion of the heating element 32 with the hollow fiber in 8 is 1
It was set to 15 ° C.

Then, the hollow fiber thus formed is cut into a length of about 600 mm and at the same time about 9,30
A hollow fiber bundle was prepared by bundling 0 pieces with a film. Then, this hollow fiber bundle is stored in an upright state in a non-coagulable liquid removing device with a blowing function, and the temperature is set to 70
℃, relative humidity 40% (heated and humidified air), air flow rate 150m
Air was blown downward from above the hollow fiber bundle for 40 minutes at 1 / min to remove the non-coagulating liquid. The remaining amount of the non-coagulating liquid in the hollow fiber thus produced was 0.1 mg or less. Further, no visual observation revealed cracks or cracks on the surface of the hollow fiber.

Then, the hollow fiber bundle from which the non-coagulable liquid has been removed is inserted into a polycarbonate resin housing, and both ends are filled with a polymer potting agent and fixed,
Blood ports are attached to both ends of the housing, and the membrane area is 1.2.
An artificial kidney of m ² was manufactured.

(Example 2) A hollow fiber bundle is stored in an upright state in a non-coagulable liquid removing device having a blowing function,
Temperature 60 ° C (warmed air), relative humidity 15%, air flow 15
The same procedure as in Example 1 was performed, except that the non-coagulable liquid was removed by blowing air from the upper side to the lower side of the hollow fiber bundle at 0 ml / min for 60 minutes. The residual amount of the non-coagulable liquid in the hollow fiber thus produced was 0.
It was 1 mg or less. Further, no visual observation revealed cracks or cracks on the surface of the hollow fiber.

(Embodiment 3) A hollow fiber bundle is stored in an upright state in a non-coagulating liquid removing device having a blowing function,
Temperature 27 ° C, relative humidity 70% (humidified air), air flow 15
The same procedure as in Example 1 was performed except that the non-coagulable liquid was removed by blowing air from the upper side to the lower side of the hollow fiber bundle at 0 ml / min for 240 minutes. The residual amount of the non-coagulable liquid in the hollow fiber thus produced was 0.
It was 1 mg or less. Further, no visual observation revealed cracks or cracks on the surface of the hollow fiber.

(Example 4) As a non-coagulable liquid to be filled in the spinning dope, NS Clean 110 (manufactured by Nikko Petrochemical Co., Ltd., n-undecane 99%, flash point 68 ° C, boiling point 189 to 194 ° C, steam) Pressure 7.1 Torr, density 0.74
4 (15 ° C.)] was used. The remaining amount of the non-coagulating liquid in the hollow fiber thus produced was 0.1 mg or less. Further, no visual observation revealed cracks or cracks on the surface of the hollow fiber. In the above-described examples, the example in which the temperature was adjusted using the controlled air (the temperature and the humidity of which were adjusted) was dried until the residual amount of the non-coagulable liquid was 0.1 mg or less. The removal work time was short and the removal efficiency was high.

(Experiment 1) With respect to the hollow fibers of Examples 1 to 4, the ultrafiltration rate was measured and the results are shown in Table 1.

[0038]

[Table 1]

The ultrafiltration rate (UFR) was measured as follows. First, as described above, an artificial dialyzer was prepared using the hollow fiber of each example, and after confirming that there were no pinholes and leaks, the artificial dialyzer was set to 37 ± 1.
Moistened with warm water at ℃, then after 3 minutes or more,
Close one of the blood ports of the artificial dialyzer and press (0.75
(kg / cm ² = 551 mmHg), the amount of water removed in 30 seconds was measured by a leak tester, and calculated by the following formula.

Ultrafiltration rate (ml / mmHg · hr · m ² )
= Measured value (ml) / Pressure (mmHg) -Time (hr)-
Area (m ² )

(Experiment 2) The dialysis ability of the hollow fibers of Examples 1 to 4 was measured and the results are shown in Table 2.

[0042]

[Table 2]

The dialysis ability was measured as follows. First, using the hollow fiber of each example as described above,
After making an artificial dialyzer and confirming that there are no pinholes and leaks, a solution (standard solution) in which various molecular weight substances are dissolved is run as blood substitute, while commercially available clearance cleaning water is run as a dialysate substitute. , Blood side flow rate is 200 ml / min, dialysate side flow rate is 500 ml / mi
n, and circulate for 10 minutes. After this, the concentration of the water for cleaning the clearance (filtrate) is colorimetrically determined to determine the content corresponding to the absorbance of the filtrate (sample) from the calibration curve,
Clearance was calculated.

Clearance (ml / min) = [standard solution concentration (mg / dl) -content corresponding to the absorbance of the sample (mg / dl)] × 200 / standard solution concentration (mg / d)
l)

[0045]

INDUSTRIAL APPLICABILITY The method for producing a hollow fiber for dialysis according to the present invention extrudes a spinning dope into a tubular shape and at the same time exhibits non-coagulation properties with respect to the spinning dope, has a flash point of 30 ° C. to 95 ° C. and a boiling point of 105. C. to 240.degree. C., vapor pressure at 60.degree.
A non-coagulable liquid of 8 to 60 Torr was introduced and filled and extruded. The extruded spinning solution was coagulated and regenerated,
After cutting the regenerated hollow fiber, air is blown to remove the non-coagulable liquid inside the hollow fiber. In particular, the above-mentioned non-coagulable liquid filled and injected into the spinning dope is used, and the non-coagulable liquid is removed by blowing air without using a cleaning liquid such as CFC.
Therefore, in the manufacturing process of the hollow fiber, it is possible to manufacture the hollow fiber having sufficient dialysis ability without using CFCs which have a problem in the global environment.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of a manufacturing apparatus used in the method for manufacturing a dialysis hollow fiber of the present invention.

FIG. 2 is a schematic view showing another example of a production apparatus used in the method for producing a hollow fiber for dialysis of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hollow fiber manufacturing apparatus 2 Discharge apparatus 5 Non-coagulating liquid inlet 7 Spinning raw liquid inlet 4 Bath (non-coagulating liquid tank) 9 Turning rod 10 Roller 11 Roller 12 Conveying device 13 Alkaline aqueous solution spraying device 14 Water spraying device 15 Acid aqueous solution spraying device 16 Second water spraying device 17 Plasticizing treatment tank 18 Dryer 20 Roller 19 Bobbin 22 Hollow fiber

Claims (2)

[Claims] 1. A spinning stock solution is extruded into a tubular shape, and at the same time, shows a non-coagulation property with respect to the spinning stock solution and has a flash point of 3 or less.
0 ° C. to 95 ° C., boiling point 105 ° C. to 240 ° C., vapor pressure at 60 ° C. is 0.8 to 60 torr, the non-coagulable liquid is introduced, filled and extruded, and the extruded spinning dope is coagulated and regenerated, A method for producing a hollow fiber for dialysis, which comprises cutting the coagulated / regenerated hollow fiber and then removing the non-coagulable liquid inside the hollow fiber by blowing air. 2. The spinning dope is extruded into a tubular shape, and at the same time, the spinning dope is non-coagulating with respect to the spinning dope and has a flash point of 3
A spinning stock solution discharge step of introducing and filling a non-coagulating liquid having a vapor pressure of 0.8 to 60 Torr at 0 ° C. to 95 ° C., a boiling point of 105 ° C. to 240 ° C., and 60 ° C., and an extruded spinning stock solution. A coagulation / regeneration step of passing through a coagulating liquid,
A re-coagulation step of treating with an alkaline aqueous solution, a washing step of washing with water, an acid treatment step of treating with an acid aqueous solution,
The rewashing step, the plasticizing step, the drying step, the winding step for winding the dried hollow fiber, the cutting step for cutting the wound hollow fiber into a predetermined length, and the cut hollow fiber Dialysis characterized by having a bundle-forming step of bundling into a bundle and a non-coagulable liquid removing step of blowing a gas into the hollow fibers formed in the bundle to remove the non-coagulable liquid inside the hollow fibers For manufacturing a hollow fiber for use.