JP2011072814A - Blood processing filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blood processing filter which hardly causes cohesiveness between a container and a filtering element even when the positive pressure on the inlet side and the negative pressure on the outlet side are generated on filtering, which can thereby hasten a blood processing speed by securing the uniform flow of blood, and further which excels in the sterilization in an autoclave. <P>SOLUTION: In the blood processing filter 1A for removing the leukocyte from a blood product, the sheet-like filtering element 9 is fixed at least to either of an inlet side container 11 and an outlet side container 12A with the vicinity of its peripheral part, and the internal space of the filter container 7A formed of the inlet side container 11 and the outlet side container 12A has been partitioned into the inlet side and the outlet side by the filtering element 9. A portion or all of the inlet side container 11 is made of a flexible resin with a vapor permeation, and a portion or all of the outlet side container 12A is made of a resin harder than a part of inlet side container 11 made of the flexible resin. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a blood treatment filter for removing undesirable components such as aggregates and leukocytes from blood. In particular, it relates to precise and disposable blood treatment filters used for the purpose of removing microaggregates and white blood cells that cause side effects from whole blood preparations for blood transfusion, erythrocyte preparations, platelet preparations, plasma preparations, etc. In particular, the present invention relates to a blood processing filter in which a resin material or the like is used as a material of a container.

  It is becoming common for whole blood collected from a donor to be separated into blood component preparations such as erythrocyte preparations, platelet preparations, plasma preparations, etc., stored, and then transfused. In addition, since microaggregates and leukocytes contained in these blood products cause various side effects of blood transfusion, these undesired components are removed before blood transfusion or blood transfusion, or after blood collection, these are undesirable. Many methods are used for transfusion after removing the components and storing them.

  The most common method for removing leukocytes from a blood product is to treat the blood product with a leukocyte removal filter. For the leukocyte removal filter, a filter element made of nonwoven fabric or porous material is used for the container, which is the same as or similar to that used for the bag of the blood collection separation set, and has excellent flexibility and vapor permeability. Two types are used: a leukocyte removal filter in a flexible container, or a filter element made of a nonwoven fabric or a porous material filled in a hard container such as polycarbonate.

  Normally, when processing blood with these leukocyte removal filters, the bag containing the blood product to be processed, which is connected to the blood inlet side of the filter via a conduit, is positioned 20 to 100 cm higher than the filter. The blood product is passed through the filter by the action of gravity, and the filtered blood product is stored in a collection bag connected to the blood outlet side of the filter via a conduit. In the case of the leukocyte removal filter of the flexible container, a pressure loss occurs due to the resistance of the filter element during the filtration, and the space on the filter inlet side becomes a positive pressure. In the case of a filter made of a flexible container, since the container is flexible, this positive pressure causes the container to expand in a balloon shape, and the filter element is pressed against the container on the outlet side.

  On the other hand, the gap between the outlet-side container and the filter element is for storing blood after filtration, which is placed at a position 50 to 100 cm lower than the normal filter, because the blood in the conduit connected to the outlet falls by gravity. This action causes a negative pressure, and the flexible container tends to adhere to the filter element. That is, the filter element comes into close contact with the outlet-side container by double force, and the blood flow is inhibited.

  In order to prevent the filter element and the outlet side container from being in close contact with each other, it is also possible to adopt a hard container such as polycarbonate that can be used at the time of relatively inexpensive autoclave sterilization. However, considering that the entire apparatus needs to be sterilized because it is used for processing blood products, when the hard container is filled, the vapor permeability is poor and a long sterilization time is required. In addition, when autoclaving for a long time causes deterioration of the blood preservation solution, etc., it is necessary to carry out complicated work such as sterilization after connecting the blood bag, circuit, etc. after sterilizing with a filter alone. It was.

  The problem of the present invention is that even when a positive pressure on the inlet side and a negative pressure on the outlet side occur during filtration, the container and the filter element are difficult to adhere to each other, and as a result, a uniform blood flow is ensured. An object of the present invention is to provide a blood treatment filter that can increase the speed and is excellent in sterilization in an autoclave.

  As a result of diligent research to solve the above problems, the inventors have found that, for example, at least a part of the container on the inlet side can be made a flexible film having high vapor permeability, thereby improving the sterility of the autoclave. Got. Conventionally, the inlet-side container and the outlet-side container are generally made of the same material in order to improve the efficiency in manufacturing, but only the outlet-side container is positively made of a hard resin. As a result, it has been found that even if negative pressure occurs, the outlet side container and the sheet-like filter element are difficult to adhere to each other. In other words, the inventors made the resin on the outlet side a hard resin, which was excellent in sterilization in the autoclave and prevented the flow obstruction on the outlet side, so that the blood flowed uniformly through the filter element and the filtration time was greatly increased. In addition to being shortened, it has been found that the filtration efficiency is dramatically improved because the filter medium is used effectively, and the present invention has been obtained.

  That is, the present invention is a filter for removing leukocytes from a blood product, and a sheet-like filter element is fixed to at least one of an inlet side container and an outlet side container in the vicinity of the peripheral edge thereof, and the inlet side container And a blood treatment filter in which the inner space of the filter container formed by the outlet side container is partitioned into an inlet side and an outlet side by a filter element, and a part or all of the inlet side container may be vapor permeable. The blood treatment filter is made of a flexible resin, and a part or all of the outlet side container is made of a hard resin as compared with a part made of the flexible resin of the inlet side container.

  According to the above-described blood treatment filter, even when a positive pressure on the inlet side and a negative pressure on the outlet side occur during filtration, it is difficult to make contact between the outlet-side container and the sheet-like filter element. The blood processing speed can be increased by securing a proper flow, and the sterilization in the autoclave can be further improved.

  The portion made of a hard resin in the outlet side container is made of a resin having a Young's modulus of 1 MPa or more at room temperature, and the portion made of a flexible resin in the inlet side container is made of a resin having a Young's modulus of less than 1 MPa at room temperature. It can also be set as the blood processing filter which becomes.

  According to the present invention, even when a positive pressure on the inlet side and a negative pressure on the outlet side occur during filtration, it is difficult to make close contact between the outlet side container and the sheet-like filter element. The blood processing speed can be increased by securing the sterilization property, and the sterilization property in the autoclave can be further improved.

FIG. 1 is a plan view of a blood processing filter according to the first embodiment of the present invention. 2 is a longitudinal sectional view taken along line II-II in FIG. FIG. 3 is an explanatory diagram showing an outline of the filtration system. FIG. 4 is a schematic cross-sectional view showing a preparation step in the method for manufacturing a blood treatment filter according to the first embodiment. FIG. 5 is a schematic cross-sectional view showing a first step in the method for producing a blood treatment filter according to the first embodiment. FIG. 6 is a schematic cross-sectional view showing a second step and a third step in the method for manufacturing a blood treatment filter according to the first embodiment. FIG. 7 is a cross-sectional view of a blood treatment filter according to the second embodiment of the present invention. FIG. 8 is a cross-sectional view of a blood treatment filter according to a third embodiment of the present invention.

  Embodiments of the present invention will be described below with reference to the drawings. The blood described in the embodiments includes blood products such as whole blood products for transfusion, erythrocyte products, platelet products, and plasma products. In addition, the outer shape of the blood treatment filter can adopt various forms such as a rectangular shape, a disc shape, an oblong disc shape, and an elliptical shape, but a rectangular shape is preferable in order to reduce material loss during manufacturing. In the embodiment, a rectangular shape will be described as an example.

  First, the blood processing filter 1A according to the first embodiment will be described with reference to FIG. 1 and FIG. The blood processing filter 1A includes a filter container 7A having a blood inlet 5 and an outlet 6, and a sheet-like blood processing filter element arranged so as to partition the internal space of the filter container 7A into an inlet side space 2 and an outlet side space 4. 9 and. In the following description, when the plane along the blood treatment filter element 9 is assumed to be the first plane, and the virtual plane including the center of the inlet 5 and the center of the outlet 6 is assumed to be the second plane, the first plane A direction along the line of intersection with the second plane is defined as a vertical direction Da, and a direction perpendicular to the vertical direction Da and along the first plane is defined as a horizontal direction Db.

  The filter container 7A is a rectangular flat container. The flat shape is intended to be a shape with a small thickness and a wide surface. The filter container 7A includes an inlet side container 11 on the inlet 5 side and an outlet side container 12A on the outlet 6 side. The inlet-side container 11 is a flexible sheet-like member, and the outlet-side container 12A is harder than the inlet-side container 11, and thus is a box-shaped member having higher shape stability than the inlet-side container 11. is there.

  The inlet side container 11 and the outlet side container 12A are arranged so as to sandwich the rectangular blood processing filter element 9, and the peripheral edge (peripheral part) of the blood processing filter element 9 is bonded to the inlet side container 11. The band-shaped adhesive region along the peripheral edge of the blood treatment filter element 9 is the inner seal portion 7a, and the inner region inside the inner seal portion 7a is a filtration region where blood flows. In the present embodiment, the peripheral edge of the blood processing filter element 9 is bonded to the inlet side container 11, but the peripheral edge of the blood processing filter element 9 is sandwiched between both the inlet side container 11 and the outlet side container 12A. Alternatively, the inner seal portion 7a may be formed by bonding the peripheral edge of the blood processing filter element 9 to the outlet side container 12A.

  The outlet side container 12A includes a rectangular plate-shaped outlet wall 12a and a peripheral wall 12b erected in a step shape along the periphery of the outlet wall 12a. The upper end of the peripheral wall 12a is bonded to the peripheral edge of the inlet side container 11 outside the inner seal portion 7a. A linear adhesion region where the peripheral edge of the inlet side container 11 and the peripheral wall 12a of the outlet side container 12A are directly bonded is the outer seal portion 7b.

  The inlet side container 11 is integrally formed with an inlet side port portion 13 to which a conduit 14A such as a blood tube for transferring blood is connected. The inlet-side port portion 13 is disposed so as to be shifted to the one end portion 7c side in the longitudinal direction Da of the filter container 7A.

  An inlet 5 is formed in the inlet-side port portion 13, and a connecting hole 20 </ b> A is formed in the inlet 5 to which a conduit 14 </ b> A is fitted and fixed. An inlet channel 13 c communicating with the inlet 5 is formed inside the inlet-side port portion 13. The inlet channel 13c communicates with the inside (filtering region) of the filter container 7A. In addition, although the inlet side port part 13 which concerns on this embodiment is integrally molded by the inlet side container 11, the inlet side port part 13 and the inlet side container 11 were formed by another member, and were integrated by welding etc. An aspect may be sufficient.

  On the outlet wall 12a of the outlet-side container 12A, an outlet-side port portion 15A that forms the blood outlet 6 is integrally formed. An outlet 6 is formed in the outlet-side port portion 15A, and a connecting hole 20B is formed in the outlet 6 to which a conduit 14B is fitted and fixed. An outlet channel 15c communicating with the outlet 6 is formed in the outlet port portion 15A. The outlet channel 15c communicates with the inside (filtering region) of the filter container 7A. Although the outlet side port portion 15A according to the present embodiment is integrally formed with the outlet side container 12A, the outlet side port portion 15A and the outlet side container 12A are formed by separate members and integrated by welding or the like. An aspect may be sufficient.

  The inlet side container 11 is made of a flexible resin having at least a part of vapor permeability. In particular, if the area of 10% or more is made of flexible resin, the inlet side container 11 has water vapor permeability during autoclave sterilization. This improves the sterilization time, which is preferable.

  The flexible resin constituting part or all of the inlet side container 11 is formed of a resin having a Young's modulus of less than 1 MPa at room temperature. In particular, it is preferably formed from a sheet-like member made of a flexible synthetic resin, and more preferably a thermoplastic resin. In addition, the measurement of Young's modulus can use the result measured according to ISO527-1.

  The flexible resin forming the inlet side container 11 on the premise that the above requirements are satisfied is, for example, soft polyvinyl chloride, polyurethane, ethylene-vinyl acetate copolymer, polyolefin such as polyethylene and polypropylene, Hydrogenated product of styrene-butadiene-styrene copolymer, thermoplastic elastomer such as styrene-isoprene-styrene copolymer or its hydrogenated product, and thermoplastic elastomer and softener such as polyolefin, ethylene-ethyl acrylate, etc. A mixture etc. are mentioned as a suitable material. Since contact with blood is considered, soft vinyl chloride, polyurethane, polyolefin, and thermoplastic elastomers based on these are preferably used as materials for medical products such as blood bags, and more preferably Soft vinyl chloride.

  On the other hand, the entire outlet side container 12 </ b> A according to the present embodiment is made of a hard resin as compared with the portion made of the flexible resin of the inlet side container 11. Specifically, a resin having a Young's modulus of 1 MPa or more at room temperature is preferable, and a resin having a Young's modulus of 2 MPa or more is more preferable. For example, polycarbonate, polyester, polyamide, polystyrene, ABS, polyethylene, polypropylene, polyvinyl chloride and the like can be used. More preferred are polycarbonate, polyester, polyamide and the like having high heat resistance. In addition, the measurement of Young's modulus can use the result measured according to ISO527-1.

  For example, when a container is manufactured by bonding an outlet side container and an inlet side container by welding or the like, if different materials are bonded together to form a container, the thermal characteristics and plasticity series are different, and further bonding is performed. Special considerations are also required for surface peeling. Therefore, it is usual to manufacture a filter container using an outlet side container and an inlet side container of the same material. However, in the blood processing filter 1A according to the present embodiment, the outlet side container 12A is made using a hard resin different from the flexible resin of the inlet side container 11, and the outlet side container 12A and the inlet side container 11 are connected. Since the filter container 7A is manufactured by welding, the filter container 7A is manufactured based on a completely different concept from a normal development concept. The reason will be described.

  The blood treatment filter 1A can be used for filtration using gravity. For example, as shown in FIG. 3, a filtration system 20 to which a blood treatment filter 1A is applied includes a storage bag 21 that contains blood after blood collection, a blood treatment filter 1A, and a collection bag 22 that accumulates blood after filtration. . The storage bag 21 and the inlet side port portion 13 of the blood processing filter 1A are connected to each other by a conduit 14A such as a blood tube, and the recovery bag 22 and the outlet side port portion 15A of the blood processing filter 1A are connected to a conduit such as a blood tube. 14B are connected to each other. Furthermore, an opening / closing means 22 such as a roller clamp for opening and closing the flow path, a chamber 23, and the like are attached to the upstream conduit 14A. The storage bag 21 containing the collected blood is placed at a position about 50 cm higher than the blood treatment filter 1A, and the collection bag 22 for collecting the filtered blood is placed at a position about 100 cm lower than the blood treatment filter 1A. ing. When the flow path of the filtration system 20 is opened and filtration is started, the negative pressure applied to the blood treatment filter outlet side during filtration becomes about −40 kPa.

  Here, for example, when the material of the container on the outlet side is the same as the material of the container on the inlet side, for example, when manufactured using a soft material having a Young's modulus of 1 MPa or less such as PVC, The non-woven fabric and the container on the outlet side are in close contact with each other and the space is closed. In order to prevent a decrease in the filtration flow rate, a gap of 0.1 mm or more, preferably 0.5 mm or more is required between the nonwoven fabric and the container on the outlet side. The resistance on the outlet side of the blood treatment filter increases, resulting in a decrease in the filtration flow rate.

  On the other hand, in the blood processing filter 1A according to the present embodiment, a hard resin having a Young's modulus of 1 MPa or more at room temperature, more preferably a hard resin having a pressure of 2 MPa or more is used to withstand the negative pressure on the outlet side during filtration. Thus, the outlet side container 12A is formed. As a result, a configuration capable of withstanding the negative pressure on the outlet side during filtration can be realized as the outlet side container 12A, a sufficient gap on the outlet side can be secured, and a decrease in the flow rate can be prevented.

  The blood treatment filter element 9 according to the present embodiment is a known filtration medium such as a fibrous porous medium such as a nonwoven fabric or a woven fabric, or a porous body having three-dimensional network-like continuous pores such as a sponge-like structure. Those that can be used and do not have excellent weldability such as mesh and screen are not applicable. Examples of materials suitable for use as the blood treatment filter element 9 include polypropylene, polyethylene, styrene-isobutylene-styrene copolymer, polyurethane, polyester, and the like. When the blood treatment filter element 9 is a nonwoven fabric, it is particularly preferable from the viewpoint of productivity.

  The sheet-like blood treatment filter element 9 may be a single filter element or may be formed from a plurality of filter elements. When formed from a plurality of filter elements, a first filter element that removes microaggregates arranged upstream (inlet 5 side) and a leukocyte arranged downstream of the first filter element are removed. Preferably it comprises a second filter element. For example, a filter material made of a nonwoven fabric having a fiber diameter of several to several tens of μm is arranged on the inlet 5 side as a first filter element for removing aggregates, and then the fiber diameter is 0.3 to 3.0 μm. A filter material made of a non-woven fabric can be used as a second filter element for removing white blood cells, and a post filter having a specific space on the downstream side can be laminated.

  Each of the first and second filter materials may further be composed of a plurality of types of filter materials, or only one of them may be composed of a plurality of types of filter materials. For example, the 1st filter which consists of a nonwoven fabric with a fiber diameter of 30-40 micrometers and / or a nonwoven fabric with a fiber diameter of 10-20 micrometers (it consists of at least one of a nonwoven fabric with a fiber diameter of 30-40 micrometers, and a fiber diameter of 10-20 micrometers) The material is disposed on the upstream side (inlet 5 side), and the nonwoven fabric having a fiber diameter of 1.5 to 2.5 μm and / or the nonwoven fabric having a fiber diameter of 0.5 to 1.8 μm is disposed downstream of the first filter material. A second filter material (consisting of at least one of a nonwoven fabric having a fiber diameter of 1.5 to 2.5 μm and a nonwoven fabric having a fiber diameter of 0.5 to 1.8 μm) may be used. Moreover, although the nonwoven fabric of a thick fiber diameter and the nonwoven fabric of a thin fiber diameter may be arrange | positioned alternately, it is more preferable that the nonwoven fabric of a thick fiber diameter is arrange | positioned upstream (inlet 5 side).

  Next, a method for manufacturing the blood treatment filter 1A will be described with reference to FIGS. 4 to 6 show an example of a procedure for manufacturing the blood treatment filter 1A, FIG. 4 shows a preparation step, FIG. 5 shows a first step, and FIG. 6 shows a second step.

  In the method for manufacturing the blood processing filter 1A according to the present embodiment, welding is performed in a plurality of stages.

  In this manufacturing method, first, as a preparatory step, the inlet side container 11, the blood processing filter element 9, and the outlet side container 12A are set at predetermined positions so as to overlap (see FIG. 4). Next, as a first step, the inlet side container 11 is welded along the peripheral edge of the blood processing filter element 9 to form the inner seal portion 7a (see FIG. 5).

  Next, the inlet side container 11 is set so that the blood processing filter element 9 is sandwiched in the peripheral wall 12b of the outlet side container 12A. As a second step, the peripheral edge of the inlet side container 11 and the upper end of the peripheral wall 12b of the outlet side container 12A are set. And the outer seal portion 7b is formed (see FIG. 6).

  The above manufacturing method shows an example of a welding method in a plurality of stages. In addition, even if blood is put into the blood treatment filter 1A as a finished product, it does not leak out of the system, and more than 99% of the blood (blood product) put from the inlet 5 provided in the inlet side container 11 May pass through the blood treatment filter element 9 and then the other method may be used as the method for producing the blood treatment filter 1A as long as the structure exits from the outlet 6 provided in the outlet side container 12A.

  According to the blood treatment filter 1A according to the present embodiment described above, even when a positive pressure on the inlet side and a negative pressure on the outlet side occur during filtration, it is difficult for the filter container 7A and the blood treatment filter element 9 to adhere to each other. As a result, a uniform blood flow can be ensured, the blood processing speed can be increased, and sterilization in an autoclave can be further improved.

  Next, a blood processing filter according to a second embodiment will be described with reference to FIG. In addition, about the blood processing filter 1B which concerns on this embodiment, about the element and member similar to the blood processing filter 1A which concerns on 1st Embodiment, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted. In addition, the blood processing filter 1B according to the present embodiment and the blood processing filter 1C according to the third embodiment described later can be manufactured using basically the same material as the blood processing filter 1A according to the first embodiment. it can.

  The blood processing filter 1B according to the present embodiment includes a filter container 7B having a blood inlet 5 and an outlet 6 and a sheet-like blood processing disposed so that the inside of the filter container 7B is separated into the inlet 5 side and the outlet 6 side. And a filter element 9.

  The filter container 7B is a rectangular flat container. The filter container 7B includes an inlet-side container 11 on the inlet 5 side and an outlet-side container 12B on the outlet 6 side. A part of the outlet side container 12 </ b> B is made of a hard resin as compared with a portion made of the flexible resin of the inlet side container 11. As for the hard resin, specifically, a resin having a Young's modulus of 1 MPa or more at room temperature is preferable, and a resin having a Young's modulus of 2 MPa or more is more preferable.

  The inlet side container 11 and the outlet side container 12B that form the filter container 7B will be described in more detail. The inlet side container 11 has a rectangular sheet shape, and the outlet side container 12 </ b> B has a rectangular sheet portion 12 c corresponding to the outer shape of the inlet side container 11. The sheet portion 12 c is formed of the same material as that of the inlet side container 11. An opening 50 is formed in the center of the sheet portion 12c, and a box-shaped cover portion 12d is bonded to the sheet portion 12c so as to close the opening 50. The cover portion 12d is made of a hard resin compared to the portion of the inlet side container 11 made of a flexible resin.

  The inlet side container 11 and the sheet part 12c of the outlet side container 12B overlap with each other via a rectangular blood processing filter element 9, and are bonded so as to sandwich the peripheral edge (peripheral part) of the blood processing filter element 9. Yes. The band-like adhesion region along the periphery of the blood treatment filter element 9 is the inner seal portion 7c, and the inner region inside the inner seal portion 7c is a filtration region where blood flows.

  Further, the periphery of the sheet portion 12c of the outlet side container 12B and the inlet side container 11 are bonded to each other outside the inner seal portion 7c. The belt-like adhesion region where the inlet side container 11 and the sheet portion 12c are directly adhered is the outer seal portion 7d.

  The cover portion 12d of the outlet side container 12B includes a cover main body 12e corresponding to the shape of the opening 50 of the sheet portion 12c, and a step-shaped peripheral wall 12f erected along the periphery of the cover main body 12e. The peripheral wall 12f is bonded around the opening 50 of the outlet side container 12C.

  The inlet side container 11 and the sheet part 12c of the outlet side container 12B overlap with each other via a rectangular blood processing filter element 9, and are bonded so as to sandwich the peripheral edge (peripheral part) of the blood processing filter element 9. Yes. The band-like adhesive region along the peripheral edge of the blood treatment filter element 9 is the inner seal portion 7c, and the inner region inside the inner seal portion 7a is a filtration region where blood flows.

  Further, the periphery of the sheet portion 12c of the outlet side container 12B and the inlet side container 11 are bonded to each other outside the inner seal portion 7c. The belt-like adhesion region where the inlet side container 11 and the sheet portion 12c are directly adhered is the outer seal portion 7d.

  The cover portion 12d of the outlet side container 12B includes a cover main body 12e corresponding to the shape of the opening 50 of the sheet portion 12c, and a step-shaped peripheral wall 12f erected along the periphery of the cover main body 12e. The peripheral wall 12 f is bonded around the opening 50 of the inlet side container 11.

  The cover body 12e is integrally formed with an outlet-side port portion 15B that forms the blood outlet 6. An outlet 6 is formed in the outlet-side port portion 15B, and a connecting hole 20B is formed in the outlet 6 to which the conduit 14B is fitted and fixed. An outlet channel 15c communicating with the outlet 6 is formed inside the outlet side port portion 15B. The outlet channel 15c communicates with the inside of the filter container 7B.

  According to the blood processing filter 1B according to the present embodiment, even when a positive pressure on the inlet side and a negative pressure on the outlet side are generated during filtration, the filter container 7B and the blood processing filter element 9 are difficult to be in close contact with each other. In addition, a uniform blood flow can be ensured to increase the blood processing speed, and the sterilization in the autoclave can be further improved.

  Next, a blood processing filter according to a third embodiment will be described with reference to FIG. The blood processing filter 1C according to the present embodiment is substantially the same as the blood processing filter 1A according to the first embodiment, except for the outlet side container 12C. Therefore, the description will be focused on the outlet side container 12C, and the same elements and members as those of the blood processing filter 1A according to the first embodiment will be denoted by the same reference numerals and detailed description thereof will be omitted.

  The filter container 7C is a rectangular flat container. The filter container 7C includes an inlet-side container 11 on the inlet 5 side and an outlet-side container 12C on the outlet 6 side. A filter container 7C is formed by the inlet side container 11 and the outlet side container 12C.

  The outlet-side container 12C includes a rectangular plate-shaped outlet wall 12g and a step-shaped peripheral wall 12h erected along the periphery of the outlet wall 12g. The outlet wall 12g forms an outlet for forming the blood outlet 6 The side port portion 15C is integrally formed. An opening 51 is formed in a part of the outlet wall 12g, and a sheet portion 12j is bonded so as to close the opening 51.

  The outlet side container 12C is made of a resin that is harder than the portion made of the flexible resin of the inlet side container 11 except for the sheet portion 12j. As for the hard resin, specifically, a resin having a Young's modulus of 1 MPa or more at room temperature is preferable, and a resin having a Young's modulus of 2 MPa or more is more preferable. The sheet portion 12j is made of the same material as the inlet side container 11.

  According to the blood processing filter 1C according to the present embodiment, even when a positive pressure on the inlet side and a negative pressure on the outlet side are generated during filtration, the filter container 7C and the blood processing filter element 9 are hardly adhered to each other. In addition, a uniform blood flow can be ensured to increase the blood processing speed, and the sterilization in the autoclave can be further improved. Further, in this blood processing filter 1C, since a vapor permeable resin can be adopted for a part of the outlet side container 12C, the steam is also permeated from the surface on the outlet side container 12C side during autoclave sterilization. This is a suitable form for sterilization when the filter element 9 is thick.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by an Example.

  First, a method for testing the flowability of a blood treatment filter will be described below. A blood processing filter according to an embodiment of the present invention is disposed between a storage bag and a recovery bag, an inlet side conduit connected to the storage bag is connected to a blood inlet of the blood processing filter, and an outlet side conduit connected to the recovery bag is Each was connected to the blood outlet of the blood treatment filter. Moreover, as each conduit, a tube made of soft vinyl chloride having an inner diameter of 3 mm and an outer diameter of 4.2 mm was used, and the length was 60 cm. After closing the inlet-side conduit with a clamp, polyvinylpyrrolidone (hereinafter sometimes referred to as PVP) is added to distilled water for injection (manufactured by Otsuka Pharmaceutical Co., Ltd.), and the viscosity is 10.0 mPa. -500g of PVP aqueous solution prepared in s was put into the storage bag.

  The entire filtration system was suspended and the collection bag was allowed to rest on the balance, and then the clamp closing the inlet side conduit was opened and filtration was started. The PVP solution in the storage bag is emptied after the PVP solution reaches the collection bag from the time when the clamp is released, and the value of the balance on which the collection bag is loaded is read every minute. When the amount became 0.5 g or less, the collection was terminated. The time until the collection was completed was treated time, and the value of the balance at the end of the collection was taken as the collected amount.

  Further, sterilization was performed at 121 ° C. for 10 minutes using HV-50 manufactured by Hirayama Seisakusho. At that time, the sterilization level was determined using Nescos I / C card S manufactured by Alfresa Pharma Co., Ltd. inside the filter.

[Example 1]
A first filter element which is a polyester nonwoven fabric having a fiber diameter of 12 μm, a basis weight of 30 g / m ² and a thickness of 0.189 mm, a second filter element having a fiber diameter of 1.2 μm, a basis weight of 40 g / m ² and a thickness of 0.235 mm. Each of the filter elements is composed of four first filter elements on the blood inlet side, 32 second filter elements on the blood outlet side, and four first filter elements on the blood outlet side. A sheet-like blood treatment filter element (hereinafter referred to as a sheet-like filter element) was used.

A flexible inlet side container made of a vinyl chloride resin sheet with a blood inlet formed therein, the above-mentioned sheet-like filter element, and an outlet side container made entirely of polycarbonate, which is a hard resin, are arranged in this order. In the state where the sheet-like filter element is sandwiched between the inlet side container and the outlet side container, the periphery of the periphery is welded so as to be integrated with the outlet side and the inlet side container over the entire circumference, and the plane size of the filtration part is 75 mm. A blood processing filter of × 58 mm was prepared.
The results are shown in Table 1.

[Example 2]
In this example, a part of the inlet side container is a soft material, that is, a soft part made of a soft flexible resin, and the outlet side container is made of a resin harder than the soft part. Specifically, the inlet side body is formed using polycarbonate for the inlet side container, a 20 mm × 20 mm opening is formed as a filtering part in this body, and a sheet made of soft vinyl chloride is attached to the opening. And used as an inlet side container. The opening to which the soft vinyl chloride sheet is attached is a soft portion. A blood processing filter equivalent to that in Example 1 was used except for the inlet side container. The results are shown in Table 1.

[Comparative Example 1]
A blood treatment filter equivalent to that in Example 1 was prepared except that polycarbonate (hard resin) was used in the inlet side container and the outlet side container without an opening. The results are shown in Table 1.

[Comparative Example 2]
A blood treatment filter equivalent to that in Example 1 was prepared except that a flexible resin (soft resin) was used for the inlet side container and the outlet side container. The results are shown in Table 1.

  The present invention relates to a blood treatment filter for removing undesirable components such as aggregates and leukocytes from blood. In particular, it relates to a precise and disposable blood treatment filter used for the purpose of removing microaggregates and white blood cells that cause side effects from whole blood preparations for blood transfusion, erythrocyte preparations, platelet preparations, plasma preparations, etc. The present invention relates to a filter in which a resin material is used as a container material.

  DESCRIPTION OF SYMBOLS 1A, 1B, 1C ... Blood processing filter, 5 ... Inlet, 6 ... Outlet, 7A, 7B, 7C ... Filter container, 9 ... Blood processing filter element, 11 ... Inlet side container, 12A, 12B ... Outlet side container.

Claims (2)

  A filter for removing leukocytes from a blood product, wherein a sheet-like filter element is fixed to at least one of an inlet side container and an outlet side container in the vicinity of a peripheral edge thereof, and the inlet side container and the outlet side container A blood treatment filter in which the inner space of the filter container formed by the filter element is partitioned into an inlet side space and an outlet side space by the filter element, and a part or all of the inlet side container may be vapor permeable. A blood processing filter made of a flexible resin, wherein a part or all of the outlet side container is made of a hard resin compared to a part of the inlet side container made of a flexible resin.   The portion of the outlet side container made of a hard resin is made of a resin having a Young's modulus of 1 MPa or more at room temperature, and the portion of the inlet side container made of a flexible resin is made of a resin having a Young's modulus of less than 1 MPa at room temperature. Item 2. The blood treatment filter according to Item 1.

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