JP2005052716A - Hollow fiber membrane module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hollow fiber membrane module the unnecessary substance removing performance of which is not deteriorated when blood is dialyzed and in which the leakage caused by an impact of a water current or a dropping impact is not caused during water purification/circulation. <P>SOLUTION: In a hollow fiber membrane module 1, a coating layer 13 continuing from the inner surface 9a of a sealed resin layer part 9 is arranged on the outer surface of hollow fiber membranes 10 in both end parts of the membranes 10 constituting a hollow fiber membrane bundle 4. The shortest length L<SB>min</SB>of the layer 13 from the inner surface 9a on the outer peripheral surface of the bundle 4 is made to be ≥1 mm, preferably ≥2 mm, the longest length L<SB>max</SB>is made to be <6 mm, preferably ≤4 mm, and the ratio (L<SB>min</SB>)/(L<SB>max</SB>) of the shortest length to the longest length is made to be larger than 0.85. It is preferable that the packing ratio of the bundle 4 in the resin layer part 9 is made to be ≥46% and ≤65%. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a hollow fiber membrane type module, and more particularly to a hollow fiber membrane type module suitably used for a hollow fiber membrane type artificial dialyzer, blood filter, plasma separator and the like.

  Conventionally, hollow fiber membrane type artificial dialyzer, blood filter, plasma separator and the like are known as hollow fiber membrane type modules. For example, in a hollow fiber membrane type artificial dialyzer, blood (a liquid to be treated) is circulated through the inner hole of the hollow fiber membrane, and a dialysis fluid (a purification treatment liquid, etc.) is circulated outside the hollow fiber membrane through the hollow fiber membrane. Unnecessary substances in the blood are removed by performing dialysis.

  The general structure of the hollow fiber membrane module includes a cylindrical casing containing a hollow fiber membrane bundle having a resin layer portion fixed at both ends with a resin composition (potting agent) such as urethane, and both ends of the cylindrical casing. Supply of treatment liquid (blood, etc.) attached to the lid with a closure lid provided with a connection port serving as a supply port and a discharge port, and purification treatment liquid (dialysis solution, etc.) formed on the outer peripheral surface near both ends of the cylindrical casing It has a structure provided with a connection port as a port and a discharge port. In the hollow fiber membrane type module having such a structure, the breakage of the hollow fiber membrane causes a leak and causes mixing of the liquid to be treated (for example, blood) and the purification liquid (for example, dialysate). Must not.

  Therefore, various technical means have been studied conventionally (see, for example, Patent Document 1 and Patent Document 2). In these technologies, a technology is disclosed in which a tongue-shaped baffle plate is disposed at a position corresponding to the purification treatment liquid supply port and the discharge port formed on the outer peripheral surface near both ends of the cylindrical casing. In order to mitigate the impact of the water flow on the hollow fiber membrane during the entry and exit of the baffle, the arrangement position, shape, size, etc. of the baffle plate have been studied.

  On the other hand, the leak due to the damage of the hollow fiber membrane is not only when the impact is applied to the hollow fiber membrane by the water flow when the purification treatment liquid enters from the supply port or is discharged from the discharge port as described above, It also occurs due to an impact such as a drop that occurs accidentally during transportation and handling of the hollow fiber membrane module. The baffle plate described above has an excellent effect on mitigating the impact due to the entry and exit of the purification treatment liquid, but when handling the hollow fiber membrane type module, up to the effect of preventing leakage due to impact such as dropping. Did not have.

  Therefore, for the purpose of alleviating both the impact caused by water flow and the impact caused by dropping to eliminate leaks, the hollow fiber membrane module supports the purification treatment supply port and discharge port from the inside of the resin layer at both ends of the hollow fiber membrane bundle. A technique for providing a resin coating layer over the entire circumference of the hollow fiber membrane bundle up to the position where the film is made is disclosed (see Patent Document 3 and Patent Document 4). In particular, in the technique described in Patent Document 3, the coating layer made of the same resin formed product as the resin formed product that forms the sealing portion is opened from the inner surface of the sealing portion to the inner opening of the purification treatment liquid supply port and the discharge port. It is made to provide in the end part surface of a hollow fiber membrane in the state continued over the range including the area | region corresponding to (1). Further, the length from the inner surface of the sealing portion of the coating layer is gradually changed in the radial direction of the hollow fiber membrane bundle, and the outer peripheral side is provided up to a range including the region corresponding to the port inner opening, and gradually toward the center. It is shortened so that it becomes bowl-like as a whole.

  However, the techniques disclosed in Patent Document 3 and Patent Document 4 require a very long coating layer in order to ensure sufficient leakage resistance. When the length of the coating layer is increased in this way, not only the membrane area effective for mass exchange is reduced, but also the flow of the purification treatment liquid flowing outside the hollow fiber membrane may be affected by the applied coating layer. As a result, the longer the coating layer, the lower the performance of removing unnecessary substances from the hollow fiber membrane module.

  In Patent Document 3, as described above, in order to prevent a reduction in unnecessary substance removal performance, the coating layer at the radial center of the hollow fiber membrane bundle is made shorter than the outer peripheral side (that is, the coating layer is made shorter). We are studying to minimize the film area lost by the coating layer. However, when the present inventors examined the length of the coating layer in detail, if the length of the coating layer is in a region corresponding to the purification treatment liquid supply port and the discharge port as in Patent Document 3, the purification treatment liquid It is estimated that the membrane area that can be effectively utilized is greatly lost because the membrane cannot penetrate into the hollow fiber membrane bundle.

  Furthermore, by increasing the filling rate (density) of the hollow fiber membrane bundle at the position corresponding to the purification treatment liquid supply port and the discharge port in the casing, and suppressing the vibration of the hollow fiber membrane due to the flow of the purification treatment liquid, the hollow fiber A method for preventing leakage due to breakage of a film bundle has been conventionally performed. However, as described in Patent Document 3, this method makes it very difficult to load the hollow fiber membrane bundle into the casing, and conversely, when the hollow fiber membrane bundle is set in the casing, the hollow fiber membrane bundle is set. May cause damage. Therefore, in the hollow fiber membrane type module described in Patent Document 3, the filling rate (density) of the hollow fiber membrane bundle is preferably in the range of 34% to 41%.

JP 2000-42100 A JP 2000-350781 A Japanese Patent No. 3151168 JP 59-4403

  The present invention has been made in view of the circumstances as described above, and effectively prevents breakage of the end portion of the hollow fiber membrane caused by impact due to fluid or impact caused by dropping, etc. An object of the present invention is to provide an excellent hollow fiber membrane type module that can be maintained high.

  In order to achieve the above object, the present inventors have intensively studied the length of the coating layer that is continuous from the inner surface of the sealing portion (resin layer portion) to the outer surface of the hollow fiber membrane. As a result, even if the coating layer is not applied to the region corresponding to the purification treatment liquid supply port and the discharge port, that is, even if the length of the coating layer is significantly shorter than the conventional one, the following constants are obtained. If it is uniform under the conditions, it has been found that the occurrence of leaks due to impacts caused by fluids, drops, etc. can be greatly reduced, and the removal performance of unnecessary substances can be maintained high, and the present invention has been completed. .

  That is, the present invention has the following configuration in order to achieve this object.

(1) A hollow fiber membrane bundle is accommodated in a cylindrical casing, both ends of the hollow fiber membrane bundle are fixed by sealing portions, and the opening portions at both ends of the casing are sealed by the sealing portions. A supply port and a discharge port for the purification treatment liquid that form a first chamber on the inner surface side of the hollow fiber membrane and a second chamber on the outer surface side of the hollow fiber membrane and communicate with the second chamber on the outer peripheral surface in the vicinity of both ends of the casing Each of the hollow fiber membranes constituting the bundle of hollow fiber membranes in a hollow fiber membrane type module having a closed lid provided with a supply port and a discharge port for the liquid to be processed that communicate with the first chamber at both ends of the cylindrical casing A coating layer that is continuous from the inner surface of the sealing portion is provided on the outer surface of the sealing portion, and the coating layer has a minimum length L _min of 1 mm or more from the inner surface of the sealing portion on the outer peripheral surface of the bundle, and a maximum length L. _max is less than 6mm There, and hollow fiber membrane module the ratio of the shortest length and the maximum length _{(L min) / (L max} ) is equal to or greater than 0.85.

(2) The hollow fiber membrane module according to (1), wherein the coating layer has a minimum length L _min from the inner surface of the sealing portion of 2 mm or more and a maximum length L _max of 4 mm or less.

  (3) The hollow fiber membrane according to (1) or (2), wherein a filling rate of the hollow fiber membrane bundle in the sealed portion in which the opening at both ends of the casing is sealed is 46% or more and 65% or less Type module.

(4) the coating layer, that the length L from the sealing portion surface, said shorter than the length L _p to the supply port and the discharge port of the purification treatment liquid and has not reached to below the ports The hollow fiber membrane module according to any one of (1) to (3).

  According to the present invention, in the hollow fiber membrane type module, the coating layer is simply provided at the boundary between the sealing portion and the hollow fiber membrane in order to prevent the hollow fiber membrane from being damaged due to the impact caused by fluid or the impact caused by dropping. Instead, by controlling the length and shape as described above, it is possible to effectively damage the hollow fiber membrane at the boundary between the hollow fiber membrane and the sealing portion due to a physical impact such as a fluid impact or a drop. In addition, it is possible to provide a hollow fiber membrane type module that has an excellent removal performance while maintaining high without reducing the performance of removing unnecessary substances, which is the original function of the hollow fiber membrane type module. That is, it is possible to obtain a hollow fiber membrane type module that can achieve both inherently contradictory effects.

Further, the length of the coating layer is preferably set so that the shortest length L _min from the inner surface of the sealing portion is 2 mm or more and the longest length L _max is 4 mm or less. It is possible to further enhance the effect of preventing the hollow fiber membrane from being damaged due to impact caused by impact or dropping, and the removal performance of unnecessary substances.

  Moreover, the vibration of the hollow fiber membrane due to the flow of the purification treatment liquid can be suppressed by setting the filling rate of the hollow fiber membrane bundle in the sealed portion in which the opening at both ends of the casing is 46% or more and 65% or less. And leakage due to breakage of the hollow fiber membrane bundle can be further reduced.

In addition, the coating layer has a length L from the inner surface of the sealing portion shorter than a length L _p to the supply port and the discharge port of the purification treatment liquid and does not reach the bottom of each port. The material exchange performed between the first chamber and the second chamber under the port is not hindered by the coating layer, and the coating layer is applied up to the portion (under the port) that is actually impacted by a fluid such as dialysate. Even without this, it is excellent in leak resistance due to the shape of the coating layer, the filling rate of the hollow fiber membrane, etc., and it can further enhance the removal performance of unnecessary substances, which is the original function of the hollow fiber membrane type module. A hollow fiber membrane type module having excellent removal performance can be provided.

  Hereinafter, the present invention will be specifically described. FIG. 1 is a schematic cross-sectional view of a hollow fiber membrane module according to the present invention, FIG. 2 is an explanatory diagram of a severe leak test method using water flow, and FIG. 3 is a hollow fiber membrane mold of Examples and Comparative Examples 1 to 5 according to the present invention. It is a table | surface figure showing the result of having measured the leak resistance by water flow, the evaluation of the leak resistance with respect to a drop impact, and the measurement of urea clearance about each using the module.

  The hollow fiber membrane type module 1 accommodates a hollow fiber membrane bundle 4 composed of a large number of hollow fiber membranes 10 in a cylindrical casing 2. Both ends of the hollow fiber membrane bundle 4 are bonded and fixed by a resin layer portion 9 as a sealing portion formed by filling a resin composition such as polyurethane, and both opening portions of the casing 2 are respectively connected to the resin layer portion 9. It is sealed by. In addition, each said hollow fiber membrane 10 is opened in the outer surface 9b of the resin layer part 9, without the opening end of the inner hole of this hollow fiber membrane 10 being sealed. Thus, the hollow fiber membrane type module 1 forms a first chamber on the inner surface side of the hollow fiber membrane 10 and a second chamber on the outer surface side of the hollow fiber membrane 10 in the casing 2. Further, the hollow fiber membrane module 1 includes a supply port 11 and a discharge port 12 for the purification treatment liquid communicating with the second chamber on the outer peripheral surface in the vicinity of both ends of the casing 2, and positions corresponding to the ports 11 and 12. Are provided with tongue-shaped baffle plates 30 and 31. Further, the vicinity of both end portions of the casing 2 are enlarged diameter portions 14 and 15 having a larger diameter than the central portion. Then, closed lids 6 and 8 each having a supply port 5 and a discharge port 7 for the liquid to be processed leading to the first chamber are attached to both ends of the cylindrical casing 2 to constitute a hollow membrane type module.

  The hollow fiber membrane 10 includes cellulose-based hollow fiber membranes such as cellulose acetate and copper ammonia cellulose, and synthetic polymer-based hollow fibers such as polyacrylonitrile, polymethyl methacrylate, polyethylene, polyvinyl alcohol, polysulfone, polyamide, and polyethersulfone. Any membrane or the like can be used, but a hollow fiber membrane having a structure having a large number of coarse pores having a minor axis of 0.5 μm or more on the outer surface of the membrane is preferable. This is because the resin forming the coating layer enters the pores on the outer surface of the hollow fiber membrane, and the membrane can be more firmly fixed and protected.

  The hollow fiber membrane module 1 of the present invention is continuously connected to the outer surface of the end of each hollow fiber membrane 10 forming the hollow fiber membrane bundle 4 from the inner surface 9a of the resin layer portion 9 at both ends of the cylindrical casing 2. The coating layer 13 is provided.

  The material of the coating layer 13 is desirably the same material and composition from the viewpoint of adhesiveness with the resin composition forming the resin layer portion 9. Therefore, a urethane polymer, an epoxy polymer, a silicon polymer or the like generally used as a potting agent for a module can be used, but is not particularly limited.

  As the length of the coating layer 13 increases, it absorbs a physical impact caused by a fluid or a drop due to a fluid and enhances the leak suppression effect of the hollow fiber membrane. However, if the length is longer than necessary, the effective membrane area of the hollow fiber membrane decreases. Further, since the purification treatment liquid cannot flow to the center of the hollow fiber membrane bundle, the membrane area inside the hollow fiber membrane bundle cannot be used effectively, and the performance of removing unnecessary substances is greatly reduced. Specifically, as in the example of Patent Document 3, when the length of the coating layer that exhibits the leakage suppressing effect of the hollow fiber membrane is longer than necessary, and the length is 6 mm or more, In some cases, the removal performance could not be fully exhibited. Moreover, when the length of the coating layer is only a part short on the outer peripheral surface of the hollow fiber membrane bundle, the leakage suppressing effect may not be sufficient. This is presumed that the water flow concentrates on the portion where the length of the coating layer is short, causing leakage. For these reasons, the coating layer 13 for protection needs to be provided uniformly with the minimum necessary.

As proved in the examples described later, in the present invention, in order to solve this problem, the coating layer 13 on the outer surface of each hollow fiber membrane 10 constituting the hollow fiber membrane bundle 4 is formed on the outer peripheral surface of the bundle. The shortest length L _min from the inner surface 9a of the resin layer portion 9 is 1 mm or more, the longest length L _max is less than 6 mm, and the ratio of the shortest length to the longest length (L _min ) / (L _max ) is It needs to be larger than 0.85.

If the minimum length L _min of the coating layer 13 is 1 mm or more, more preferably 2 mm or more, the leakage resistance performance in an environment considered from the use / cleaning conditions of the hollow fiber membrane module is sufficient. However, if the coating layer 13 is too long, it may affect the removal performance of unnecessary substances due to a decrease in the effective membrane area. Therefore, the maximum length L _max of the coating layer 13 needs to be less than 6 mm. Is preferably 4 mm or less.

The coating layer 13 needs to have a uniform length on the outer peripheral surface of the hollow fiber membrane bundle 4, and the ratio (L _min ) / (L _max ) of the shortest length to the longest length of the coating layer 13 is 0. .85 or more is required. When the value of (minimum length L _min ) / (maximum length L _max ) is less than 0.85, the purification treatment liquid and the cleaning liquid flow into the shortest length portion of the coating layer 13 and flow into the hollow fiber membrane. Since an excessive water pressure is applied to 10, there is a higher risk that the leakage suppressing effect will be lower than when the coating layer 13 is provided uniformly on the outer peripheral surface of the hollow fiber membrane bundle. If the value of (shortest length L _min ) / (longest length L _max ) of the coating layer 13 is larger than 0.85, it is possible to exert a leak suppressing effect, and the upper limit is 1.0.

  In order to suppress impact (vibration) due to fluid impact or drop, etc., and improve leakage resistance, the filling rate of the hollow fiber membrane bundle 4 in the sealing portion 9 (blood contact surface 9b) of the hollow fiber membrane module 1 That is, it is preferable to control a value obtained by dividing the sum of the cross-sectional areas of the hollow fiber membrane 10 by the cross-sectional area at the end of the casing 2 and multiplying by 100 (hereinafter referred to as the caging end face filling rate). It is preferable to set the end face filling rate to 46% or more. This is to reduce the vibration width of the hollow fiber membrane when shocked by a water flow or a drop, and to relieve the stress itself applied to the hollow fiber membrane. Accordingly, a higher casing end face filling rate is preferable, but with a high casing end face filling rate exceeding 65%, it becomes very difficult to set the hollow fiber membrane bundle 4 inside the casing 2, and if it is set forcibly, it is hollow. In order to cause breakage of the thread film 10, it is desirable to set the caging end face filling rate to 46% or more and 65% or less.

Further, as shown in FIG. 1, the coating layer 13 has a length L from the resin layer inner surface 9a shorter than a length L _p to the supply port 11 and the discharge port 12 of the purification treatment liquid, In addition, the configuration does not reach the ports 11 and 12 below.

  When using these hollow fiber membrane type modules 1 as a blood purification processor, blood is supplied from the liquid supply port 5 to be processed and dialysate is supplied from the purification liquid supply port 11 as in the conventional apparatus. . The blood flows through the hollow portion (first chamber) of the hollow fiber membrane 10 toward the other end of the casing 2 and is discharged from the liquid discharge port 7 to be processed. The dialysate supplied from the purification treatment liquid supply port 11 is brought into contact with the outer surface of the hollow fiber membrane 10 through the gap formed between the enlarged diameter portion 15 and the end of the hollow fiber membrane bundle 4 and to the other end. Then, the liquid is discharged from the purification treatment liquid discharge port 12. At this time, waste products in the blood move to the dialysate side due to the osmotic pressure difference and concentration gradient through the surface of the hollow fiber membrane 10, and at the same time, the components deficient in the blood are supplied from the dialysate side to perform blood purification.

  At the time of use or cleaning before use, when the purification treatment liquid or the cleaning liquid is supplied and enters the gap of the hollow fiber membrane bundle 4, stress is applied to the hollow fiber membrane 10, and the resin layer portion 9 and the hollow fiber membrane are applied. The hollow fiber membrane 10 breaks in the vicinity of the boundary 10 (near the inner surface 9a) because of the stress relaxation of the coating layer 13 applied to the hollow fiber membrane bundle 4 and the high filling rate of the hollow fiber membrane bundle 4. Suppresses by suppressing the vibration.

As described above, the hollow fiber membrane type module 1 according to the present invention is near the boundary between the resin layer portion 9 and the hollow fiber membrane 10 that is stressed when the purification treatment liquid and the cleaning liquid enter (near the inner surface 9a). The coating layer 13 is provided on the outer surface of each hollow fiber membrane 10 so as to have a substantially uniform length. Specifically, on the outer peripheral surface of the bundle, the shortest length L _min is 1 mm or more, and the longest length L _max is 6 mm. And the ratio of the shortest length to the longest length (L _min ) / (L _max ) is greater than 0.85, so that the removal performance of unnecessary substances can be maintained high without causing deterioration. The leak performance is improved.

  That is, according to the present invention, in the hollow fiber membrane type module 1, the coating layer 13 is simply applied to the resin layer portion 9 and the hollow fiber membrane 10 in order to prevent the hollow fiber membrane from being damaged due to impact caused by fluid or impact caused by dropping. In the boundary portion between the hollow fiber membrane 10 and the resin layer portion 9 due to a physical impact caused by a fluid impact or a drop by controlling the length and shape thereof as described above Hollow fiber that effectively prevents breakage of the hollow fiber membrane 10 and maintains high without reducing the unnecessary substance removal performance, which is the original function of the hollow fiber membrane module 1, and has excellent removal performance The membrane module 1 can be provided.

Further, the length L of the coating layer 13, the resin layer portion surface 9a shortest length _{L min} of 2mm or more from the longest is preferably set to 4mm below the length _{L max,} thereby, by the above-described fluid It is possible to further enhance the effect of preventing the hollow fiber membrane from being damaged due to impact caused by impact or dropping, and the removal performance of unnecessary substances.

  In addition, the hollow fiber membrane 10 is vibrated by the flow of the purification treatment liquid by setting the filling rate of the hollow fiber membrane bundle 4 in the resin layer portion 9 in which the opening at both ends of the casing is sealed to 46% or more and 65% or less. It is possible to suppress the leakage due to breakage of the hollow fiber membrane bundle 4.

Further, the coating layer 13 has a length L from the inner surface of the resin layer portion shorter than a length L _p to the supply port 11 and the discharge port 12 of the purification treatment liquid, and below the ports 11 and 12. Therefore, the material exchange performed between the first chamber and the second chamber under the ports 11 and 12 is not hindered by the coating layer 13 and is actually subjected to an impact by a fluid such as dialysate. Even without providing a coating layer up to the part (ports 11 and 12 below), it has excellent leakage resistance due to the shape of the coating layer, the filling rate of the hollow fiber membrane, etc., and is the original function of the hollow fiber membrane type module. The removal performance of unnecessary substances can be further enhanced, and a hollow fiber membrane module having excellent removal performance can be provided.

  In manufacturing the hollow fiber membrane module 1, about 7000 to 14,000 hollow fiber membranes 10 are bundled to adjust the hollow fiber membrane bundle 4. At this time, a film of silicon or the like is wound around the hollow fiber membrane bundle 4. This is because by wrapping with a film, the hollow fiber membrane 10 can be prevented from being damaged, and at the same time, the hollow fiber membrane bundle 4 can be easily inserted into the casing 2.

  Subsequently, the hollow fiber membrane bundle 4 in a state where the film is wound is inserted into the casing 2, and the hollow fiber membrane bundle 4 is set in the casing 2 by extracting only the film. By such a method, the hollow fiber membrane bundle 4 can be efficiently inserted into the casing 2 at a high filling rate.

  The casing 2 in which the hollow fiber membrane bundle 4 is set is attached to a potting jig attached on the turntable of the centrifugal molding machine with the purification treatment liquid supply port 11 and the purification treatment liquid discharge port 12 facing upward. And a tube is inserted in both ports 11 and 12 from a distribution tank (not shown) for supplying the adhesive which forms resin layer part 9 by hardening.

  When the installation of the distribution tank is completed, the process moves to a potting process in which potting is performed. The potting process includes two adhesive injection processes and two centrifugal processes.

  First, in the adhesive injection step, centrifugal force is applied to both ends of the casing 2 while rotating the turntable of the centrifugal molding machine at a predetermined rotation speed, and the adhesive is injected into the distribution tank in this rotational state. Here, the adhesive is particularly a urethane-based adhesive or an epoxy-based adhesive that is generally used as a potting agent for a hollow fiber membrane type module, as long as it has fluidity at an initial stage and is cured over time. There is no limitation.

  The adhesive injected into the distribution tank is distributed to the injection tube by centrifugal force, discharged into the purification treatment liquid supply port 11 and the purification treatment liquid discharge port 12 by the tube, and falls in the ports 11 and 12 by its own weight. Then flows into the casing 2. The injected adhesive further moves toward both ends of the casing 2 by centrifugal force, and at the same time flows into the gap between the enlarged diameter portions 14 and 15 of the casing 2 and the hollow fiber membrane bundle 4 and reaches the outer periphery. Then, it penetrates into the gap between the hollow fiber membranes 10.

  The adhesive thus injected flows through the gap of the hollow fiber membrane 10 by its own gravity and centrifugal force to reach the end face of the casing 2 and fills the gap of the hollow fiber membrane 10 from the end face of the casing 2. Since the level of the adhesive increases as the injection amount of the agent increases, the length of immersion gradually from the end of the hollow fiber membrane bundle 4 is increased. That is, if a predetermined amount of adhesive is injected, the hollow fiber membrane bundle 4 having a predetermined length is immersed in the adhesive from the end. Thus, if the hollow fiber membrane bundle 4 has been immersed in the adhesive over a predetermined length, the injection of the adhesive is stopped and the process proceeds to the centrifugation step.

  The centrifugation step is a step of curing the adhesive while collecting and maintaining the adhesive at the end of the casing 2 by the rotation of the casing 2. Thereafter, the process proceeds to the second adhesive injection step.

  In the second adhesive injection step, as in the first time, the adhesive is injected into the distribution tank while maintaining rotation. The adhesive injected the second time is preferably of the same composition as the adhesive injected the first time, but the components are not particularly limited.

  The injected adhesive moves toward both ends of the casing 2 as in the first injection. However, since the adhesive injected at the first time has already hardened to form a part of the resin layer portion 9, the adhesive is in the gap between the enlarged diameter portions 14 and 15 of the casing 2 and the hollow fiber membrane bundle 4. Advancing in the circumferential direction of the bundle along the hollow fiber membrane 10. The coating layer 13 according to the present invention is different in the speed at which the adhesive is supplied to the enlarged diameter portions 14 and 15 and the speed of entering between the hollow fiber membranes 10, and the increased diameter portions 14 and 15 and the hollow fiber membrane bundle 4 are different. It is formed because the adhesive stays in the gap. The length of the coating layer 13 and the uniformity of the coating layer 13 are determined by the supply speed of the adhesive to the enlarged diameter portions 14 and 15 and the viscosity of the adhesive, which is a dominant factor for the speed of penetration of the adhesive into the hollow fiber membrane 10.

  After supplying a predetermined amount of adhesive, the cylindrical casing 2 continues to rotate as in the first centrifugation step, and the second centrifugation step is performed. At this time, since the adhesive has an appropriate viscosity, it remains on the outer surface of the hollow fiber membrane 10 soaked in the adhesive even after the adhesive flows in the end direction, Layer 13 is formed. Thus, the length of the coating layer 13 corresponds to the length of the outer surface of the hollow fiber membrane 10 immersed in the adhesive, but the supply rate of the adhesive to the casing 2 and the adhesive in the expanded diameter portions 14 and 15 are increased. The length and shape of the coating layer 13 can be controlled by factors such as the viscosity, the number of rotations during centrifugation, and the filling rate of the hollow fiber membrane 10. In the present invention, the coating layer 13 has a shape having a uniform length on the outer circumferential surface of the hollow fiber membrane bundle 4 over the entire circumference from the inner surface 9a of the resin layer portion 9.

  After the second injection adhesive is cured, the centrifugal rotation is stopped and the process proceeds to a modularization process. In order to completely cure the adhesive and produce the outer surface 9b of the smooth resin layer portion 9, the outer portion of the resin layer portion 9 protruding from the casing 2 is flush with the end opening of the casing 2. Then, both ends of each hollow fiber membrane 10 are opened, and closure lids 6 and 8 are attached to both ends to form a hollow fiber membrane module 1 as shown in FIG.

  As described above, according to the manufacturing method described above, the casing 2 is rotated so that the centrifugal force acts on both ends, and in this state, the adhesive is divided into two portions, and the purification treatment liquid supply port 11 at the end of the casing 2 is obtained. In addition, by injecting through the discharge port 12, the coating layer 13 having a substantially uniform length is formed over the entire circumference at the boundary between the resin layer 9 and the hollow fiber membrane 10 where stress is concentrated by the impact of the purification treatment liquid, the cleaning liquid, and the like. Granting is possible.

  By changing the ratio of the first injection amount and the second injection amount of the adhesive (potting agent) as the resin composition, and adjusting the injection speed and the viscosity of the adhesive when injected into the casing 2, the coating layer 13 Can be controlled with high accuracy.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to these Examples.

  First, measurement methods and evaluation methods used in the examples will be described.

[Measurement of coating layer length]
About each hollow fiber membrane type module 1 manufactured as mentioned later, the length of coating layer 13 was measured. In other words, the hollow fiber membrane 10 adjacent to the purification treatment liquid supply port 11 and the purification treatment liquid discharge port 12 is used as a starting point, and about 5 to 10 respectively at locations moved approximately 45 degrees on either side of the bundle circumference in the left or right direction. The length of the coating layer of this hollow fiber membrane was measured. The total average of these 8 locations was taken as the length of the coating layer.

[Evaluation of leakage resistance by water flow]
The leakage resistance due to the water flow during use was evaluated by assembling the circuit device shown in FIG.

As shown in FIG. 2, the pressure in the pressurized tank 20 is adjusted to about 24.5 kPa / cm ² , and the treated liquid supply port 5 and the purification treatment liquid supply port 11 of the hollow fiber membrane module 1 set in the circuit. At the same time, pressurized water was injected (injection time 2 minutes / time). Then, for each injection, air was injected into the liquid to be treated at a pressure of about 14.7 kPa / cm ² , and the occurrence of leak was repeated using the presence or absence of bubbles as an index.

  In the determination of the leak resistance due to the water flow, for example, the one in which the leak was confirmed by the 8th pressurized water injection was designated as “water flow leak resistance 8”. This operation was performed up to 25 times, and “leak resistance> 25” was set for a hollow fiber membrane type module in which no leak was confirmed even after repeated injection of pressurized water 25 times.

[Evaluation of leak resistance against drop impact]
As for leak resistance against drop impact, the impact when dropping the hollow fiber membrane module directly onto the floor surface during use is considered to be the greatest compared to the transport stage packed in the packing box. A drop fracture test was performed for each membrane module.

  First, after filling the inner surface side flow channel and the outer surface side flow channel of the hollow fiber membrane module 1 of the hollow fiber membrane module 1 with water so that the water is once full, the filled water in the outer surface flow channel is purified. Each 1.5 ml was extracted from the treatment liquid supply port 11 and the purified treatment liquid discharge port 12 to form a space in the hollow fiber membrane module 1.

The hollow fiber membrane type module 1 is placed on a concrete floor with the closing lid 8 (or the closing lid 6 protruding from the liquid port 5 to be processed) projecting downward from the 1.2 m height of the liquid discharge port 7 to be processed. Each time it was dropped, air was injected into the liquid to be treated at a pressure of about 14.7 kPa / cm ² , and the occurrence of leaks was repeatedly confirmed using the presence or absence of bubbles as an index. In the repetition of the drop test, the treatment liquid supply port 5 and the treatment liquid discharge port 7 are not specified, but are repeatedly dropped with the same port side facing downward.

  The determination of the leak resistance against the drop impact was, for example, “fall leak property 3” for the case where the leak was confirmed in the third drop. In addition, the hollow fiber membrane type module in which no leak was confirmed even after the 10th drop was repeated up to 10 times, and “falling leak property> 10” was set.

[Measurement of urea clearance]
Regarding urea removal performance, blood side flow rate 200 ml / min, dialysate side flow rate 500 ml / min, transmembrane pressure difference (TMP) 0 Pa (0 mmHg) according to dialyzer performance evaluation criteria (Japan Society for Artificial Organs, September 1982) ), The urea concentration (C _in ) on the blood inlet side and the urea concentration (C _out ) on the blood outlet side were measured, and the clearance of the solute was calculated by the following formula (1). The unit of this urea clearance is ml / min. The measurement was carried out by randomly taking 5 out of each hollow fiber membrane type module.

Urea clearance = 200 × (C _in −C _out ) / C _in (1)

  The urea clearance indicates the amount of liquid to be treated that has been purified by removing urea from the liquid to be treated that is supplied to the hollow fiber membrane module at 200 ml / min under the present measurement conditions.

<Example 1>
A hollow fiber membrane bundle 4 (9700 hollow fiber membranes) made of a semipermeable hollow fiber membrane 10 (inner diameter 200 μm, membrane pressure 45 μm) made of a polysulfone resin as a main raw material using a casing 2 having a length of 282 mm is used as the casing end face. A urethane adhesive adjusted to a viscosity of 400 to 800 mPas is loaded at a constant speed while being loaded into the casing 2 so that the filling rate is 46.0%, and the casing 2 is centrifuged at a rotation speed of 900 rpm (centrifugal temperature 50 ° C.). A predetermined amount was injected in two portions. After the urethane-based adhesive is cured, both end surfaces are cut, the inside of the hollow fiber membrane is opened to the outside, the closure lids 6 and 8 are attached, and a hollow fiber membrane type module (hereinafter referred to as a hollow fiber membrane blood treatment device) is attached. Assembled.

The values of the shortest length L _min , the longest length L _max , (the shortest length L _min ) / (the longest length L _max ) of the coating layer of the hollow fiber membrane blood processor according to Example 1 are shown in FIG. It was as shown in.

<Example 2>
The same casing 2 and hollow fiber membrane bundle 4 as in Example 1 were used. The hollow fiber membrane bundle 4 was loaded into the casing 2 so that the filling ratio of the casing end surface was 46.0%, and the viscosity was adjusted to 400 to 800 mPas while the casing 2 was centrifuged at a rotation speed of 900 rpm (centrifugal temperature 50 ° C.). A predetermined amount of urethane-based adhesive was injected in two at the 1/4 injection rate in Example 1. After the urethane adhesive was cured, both end surfaces were cut, the inside of the hollow fiber membrane was opened to the outside, and the closure lids 6 and 8 were attached to assemble a hollow fiber membrane blood treatment device.

The values of the shortest length L _min , the longest length L _max , (the shortest length L _min ) / (the longest length L _max ) of the coating layer of the hollow fiber membrane blood processor according to Example 2 are shown in FIG. It was as shown in.

<Example 3>
The same casing 2 and hollow fiber membrane bundle 4 as in Example 1 were used. The hollow fiber membrane bundle 4 was loaded into the casing 2 so that the filling ratio of the casing end surface was 65.0%, and the viscosity was adjusted to 400 to 800 mPas while the casing 2 was centrifuged at a rotational speed of 900 rpm (centrifugal temperature 50 ° C.). A predetermined amount of urethane-based adhesive was injected in two at the 1/4 injection rate in Example 1. After the urethane adhesive was cured, both end surfaces were cut, the inside of the hollow fiber membrane was opened to the outside, and the closure lids 6 and 8 were attached to assemble a hollow fiber membrane blood treatment device.

The values of the shortest length L _min , the longest length L _max , (the shortest length L _min ) / (the longest length L _max ) of the coating layer of the hollow fiber membrane blood treatment device according to Example 3 are shown in FIG. It was as shown in.

<Example 4>
The same casing 2 and hollow fiber membrane bundle 4 as in Example 1 were used. The hollow fiber membrane bundle 4 was loaded into the casing 2 so that the casing end surface filling ratio was 65.0%, and the viscosity was adjusted to 400 to 800 mPas while the casing 2 was centrifuged at a rotation speed of 900 rpm (centrifugal temperature 55 ° C.). A predetermined amount of urethane-based adhesive was injected in two at the 1/4 injection rate in Example 1. After the urethane adhesive was cured, both end surfaces were cut, the inside of the hollow fiber membrane was opened to the outside, and the closure lids 6 and 8 were attached to assemble a hollow fiber membrane blood treatment device.

The values of the shortest length L _min , the longest length L _max , (the shortest length L _min ) / (the longest length L _max ) of the coating layer of the hollow fiber membrane blood processor according to Example 4 are shown in FIG. It was as shown in.

<Comparative Example 1>
The same casing 2 and hollow fiber membrane bundle 4 as in Example 1 were used. The hollow fiber membrane bundle 4 was loaded into the casing 2 so that the casing end surface filling rate was 45.0%, and the viscosity was adjusted to 400 to 800 mPas while the casing 2 was centrifuged at a rotation speed of 900 rpm (centrifugal temperature 50 ° C.). A predetermined amount of urethane-based adhesive was injected in two at the 1/4 injection rate in Example 1. After the urethane adhesive was cured, both end surfaces were cut, the inside of the hollow fiber membrane was opened to the outside, and the closure lids 6 and 8 were attached to assemble a hollow fiber membrane blood treatment device.

The values of the shortest length L _min , the longest length L _max , (the shortest length L _min ) / (the longest length L _max ) of the coating layer of the hollow fiber membrane blood treatment device according to Comparative Example 1 are shown in FIG. It was as shown in.

<Comparative example 2>
The same casing and hollow fiber membrane bundle as in Example 1 were used. The hollow fiber membrane bundle 4 was loaded into the casing 2 so that the casing end face filling ratio was 66.0%, and the viscosity was adjusted to 400 to 800 mPas while the casing 2 was centrifuged at a rotation speed of 900 rpm (centrifugal temperature 50 ° C.). A predetermined amount of urethane-based adhesive was injected in two at the 1/4 injection rate in Example 1. After the urethane adhesive was cured, both end surfaces were cut, the inside of the hollow fiber membrane was opened to the outside, and the closure lids 6 and 8 were attached to assemble a hollow fiber membrane blood treatment device.

The values of the shortest length L _min , the longest length L _max , (the shortest length L _min ) / (the longest length L _max ) of the coating layer of the hollow fiber membrane blood treatment device according to Comparative Example 2 are shown in FIG. It was as shown in.

<Comparative Example 3>
The same casing and hollow fiber membrane bundle as in Example 1 were used. The hollow fiber membrane bundle 4 was loaded into the casing 2 so that the casing end face filling rate was 46.0%, and the viscosity was adjusted to 400 to 800 mPas while the casing 2 was centrifuged at a rotation speed of 1200 rpm (centrifugal temperature 50 ° C.). A predetermined amount of urethane-based adhesive was injected in two at the 1/4 injection rate in Example 1. After the urethane adhesive was cured, both end surfaces were cut, the inside of the hollow fiber membrane was opened to the outside, and the closure lids 6 and 8 were attached to assemble a hollow fiber membrane blood treatment device.

The values of the shortest length L _min , the longest length L _max , (the shortest length L _min ) / (the longest length L _max ) of the coating layer of the hollow fiber membrane blood processing device according to Comparative Example 3 are shown in FIG. It was as shown in.

<Comparative example 4>
The same casing and hollow fiber membrane bundle as in Example 1 were used. The hollow fiber membrane bundle 4 was loaded into the casing 2 so as to have a casing end face filling rate of 46.0%, and the viscosity was adjusted to 400 to 800 mPas while the casing 2 was centrifuged at a rotation speed of 600 rpm (centrifugal temperature 50 ° C.). A predetermined amount of urethane-based adhesive was injected in two at the 1/4 injection rate in Example 1. After the urethane adhesive was cured, both end surfaces were cut, the inside of the hollow fiber membrane was opened to the outside, and the closure lids 6 and 8 were attached to assemble a hollow fiber membrane blood treatment device.

The values of the shortest length L _min , the longest length L _max , (the shortest length L _min ) / (the longest length L _max ) of the coating layer of the hollow fiber membrane blood processor according to Comparative Example 4 are shown in FIG. It was as shown in.

<Comparative Example 5>
The same casing and hollow fiber membrane bundle as in Example 1 were used. The hollow fiber membrane bundle 4 was loaded in the casing 2 so that the casing end surface filling rate was 46.0%, and the viscosity was adjusted to 200 to 400 mPas while the casing 2 was centrifuged at a rotation speed of 900 rpm (centrifugal temperature 55 ° C.). A predetermined amount of urethane-based adhesive was injected in two at the same injection speed as in Example 1. After the urethane adhesive was cured, both end surfaces were cut, the inside of the hollow fiber membrane was opened to the outside, and the closure lids 6 and 8 were attached to assemble a hollow fiber membrane blood treatment device.

The values of the shortest length L _min , the longest length L _max , (the shortest length L _min ) / (the longest length L _max ) of the coating layer of the hollow fiber membrane blood treatment device according to Comparative Example 5 are shown in FIG. It was as shown in.

<Experimental example>
Using each of the hollow fiber membrane blood processing devices of Examples 1 to 4 and Comparative Examples 1 to 5, evaluation of leakage resistance by water flow, evaluation of leakage resistance against a drop impact, and measurement of urea clearance were performed.

The result was as shown in FIG. As is clear from FIG. 3, in the hollow fiber membrane type modules (hollow fiber membrane blood treatment devices) of Examples 1 to 4 according to the present invention, the length of the coating layer 13 is the circle of the hollow fiber membrane bundle 4. It is provided over the entire circumference, and the value of (shortest length L _min ) / (longest length L _max ) is greater than 0.85, the longest length L _max is less than 6 mm, and the shortest length L _min is The coating layer has a shape of 1 mm or more. As a result, it was possible to realize an excellent hollow fiber membrane module that is excellent in leak resistance due to water flow and leak resistance against dropping impact, and that can maintain a high unnecessary substance removal performance.

  On the other hand, in Comparative Examples 1 to 5 having a coating layer that does not satisfy the requirements of the present invention, those that simultaneously satisfy excellent leakage resistance and unnecessary substance removal performance were not obtained.

It is a cross-sectional schematic diagram for demonstrating one Embodiment of the hollow fiber membrane type module which concerns on this invention. It is a schematic explanatory drawing for demonstrating the severe leak test method by a water flow. For each of the hollow fiber membrane modules of Examples 1 to 4 and Comparative Examples 1 to 5 according to the present invention, evaluation of leakage resistance by water flow, evaluation of leakage resistance against a drop impact, and measurement of urea clearance were performed. It is a table | surface figure showing a result.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Hollow fiber membrane type module 2 ... Cylindrical casing 4 ... Hollow fiber membrane bundle 5 ... Process liquid supply port 6 ... Closure lid 7 ... Process liquid discharge port 8 ... Closure lid 9 ... Resin layer part (sealing part)
9a: Inner surface 9b of resin layer part ... Outer surface 10 of resin layer part ... Hollow fiber membrane 11 ... Purification treatment liquid supply port 12 ... Purification treatment liquid discharge port 13 ... Coating layers 14, 15 ... Expanded diameter part 20 ... Pressure Tank 30, 31 ... baffle plate

Claims (4)

A hollow fiber membrane bundle is accommodated in a cylindrical casing, both ends of the hollow fiber membrane bundle are fixed by sealing portions, and the opening portions at both ends of the casing are sealed by the sealing portions, and the hollow fiber membranes are sealed in the casing. Forming a first chamber on the inner surface side and a second chamber on the outer surface side of the hollow fiber membrane, comprising a supply port and a discharge port for the purification treatment liquid leading to the second chamber on the outer peripheral surface in the vicinity of both ends of the casing; In the hollow fiber membrane type module in which the closure lid provided with the supply port and the discharge port of the liquid to be processed leading to the first chamber is attached to both ends of the cylindrical casing,
A coating layer continuous from the inner surface of the sealing portion is provided on the outer surface of the end portion of each hollow fiber membrane constituting the hollow fiber membrane bundle, and the coating layer has the shortest length from the inner surface of the sealing portion on the outer peripheral surface of the bundle. A hollow having a length L _min of 1 mm or more, a maximum length L _max of less than 6 mm, and a ratio (L _min ) / (L _max ) of the shortest length to the longest length of greater than 0.85 Yarn membrane module. The hollow fiber membrane module according to claim 1, wherein the coating layer has a minimum length L _min from the inner surface of the sealing portion of 2 mm or more and a maximum length L _max of 4 mm or less. The hollow fiber membrane type module according to claim 1 or 2, wherein a filling rate of the hollow fiber membrane bundle in the sealing portion where the casing opening portions are sealed is 46% or more and 65% or less. The coating layer has a length L from the sealing portion inner surface is shorter than the length L _p to the supply port and the discharge port of the purification process liquid, and wherein the not yet up under each port The hollow fiber membrane type module according to any one of claims 1 to 3.

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