CN211885768U - blood processing filter - Google Patents

Abstract

The utility model relates to a blood processing filter. The blood processing filter includes a flexible container sandwiching and sealing the filter element, and a filter element including at least an inlet-side filter layer, an intermediate filter layer, and an outlet-side filter layer arranged in layers layer, the inlet side filter layer and the outlet side filter layer are made of polyethylene terephthalate, the middle filter layer is made of polybutylene terephthalate, the flexible container Melt mixing with the filter element forms a composite layer. The blood processing filter of the utility model can effectively improve the centrifugation resistance.

Description

blood processing filter

technical field

The utility model relates to the technical field of filters, in particular to a blood processing filter.

Background technique

Whole blood collected from donors is used as a raw material for blood component preparations, such as red blood cell preparations, platelet preparations, and plasma preparations. Whole blood includes undesirable components such as microaggregates and leukocytes that can cause various transfusion side effects. Therefore, unwanted components are typically removed after blood collection and prior to use of blood component preparations.

Methods for removing undesired components (eg, leukocytes) from whole blood and blood component preparations include the use of fibrous aggregates (eg, nonwovens) and porous structures with continuous pores, which are simple to operate and low cost . Filtration methods using blood treatment filters containing filter media have become popular.

Conventionally, blood treatment filters in which rigid containers such as polycarbonate are filled with filter materials made of non-woven fabrics or porous materials have been widely used. However, due to the low gas permeability of these containers, steam sterilization is not required. This method is widely used in the sterilization of blood collection and separation devices, but it is difficult to use this container. In addition, a closed system includes a case where leukocytes are first removed from the whole blood product after blood collection, a blood processing filter is separated, and then a centrifugation operation for component separation is performed, or the whole blood is separated into a plurality of blood by a centrifugation operation After the components are removed, the leukocytes are removed. In the latter case, the blood processing filter is required to be centrifuged together with the blood collection tube separation device. At this point, the rigid container may damage the bag or catheter, or the rigid container itself may not be able to withstand the stress of the centrifugation process and be damaged.

As a solution to these problems, a flexible blood processing filter has been developed using a flexible blood processing filter having the same or similar flexibility and excellent vapor transmission as the bags used for blood collection tubes/separation kits sexual material.

When welding non-porous materials such as soft polyvinyl chloride sheets and olefin films, such as lifebuoys, blood bags, plastic bags, etc., to each other, pressure and load, so it has always been required to have excellent peel resistance and centrifugation resistance. As a technique for producing a melt satisfying the requirements, welding techniques such as high-frequency welding and heat sealing have been widely used (for example, Japanese Patent Laid-Open No. 2007-253374A, WO03059611), but a product with sufficient centrifugal force resistance and peeling resistance has never been obtained. .

Utility model content

Based on the above-mentioned defects in the prior art, the purpose of the present invention is to provide a blood processing filter which can improve its centrifugation resistance.

Therefore, the present invention provides the following technical solutions.

The utility model provides a blood treatment filter, which comprises a flexible container and a filter element,

the flexible container grips the filter element and is sealed,

The filter element includes at least an inlet side filter layer, an intermediate filter layer and an outlet side filter layer arranged in layers, and the inlet side filter layer and the outlet side filter layer are made of polyethylene terephthalate, The intermediate filter layer is made of polybutylene terephthalate,

The flexible container is melt-mixed with the filter element to form a composite layer.

In at least one embodiment, the blood processing filter includes a first sealing portion formed as an endless belt by welding the flexible container and the filter element.

In at least one embodiment, the blood processing filter includes a second sealing portion formed on the outer side of the first sealing portion so as to surround the first sealing portion, formed by welding the flexible container.

In at least one embodiment, the flexible container includes an inlet-side flexible container and an outlet-side flexible container, and the inlet-side flexible container, the inlet-side filter layer, and the intermediate filter layer are melt-mixed to form a first composite layer.

In at least one embodiment, the flexible container includes an inlet-side flexible container and an outlet-side flexible container, and the intermediate filter layer, the outlet-side filter layer, and the outlet-side flexible container are melt-mixed to form a second composite layer.

In at least one embodiment, in the thickness direction of the filter element, the fiber diameter or pore size of the filter element is stepped or continuous from the portion of the filter element that contacts the flexible container decrease.

In at least one embodiment, the fiber diameter or pore size of the inlet-side filter layer is larger than the fiber diameter or pore size of the intermediate filter layer, and the fiber diameter or pore size of the outlet-side filter layer is larger than the fiber diameter or pore size of the intermediate filter layer. or aperture.

In at least one embodiment, the flexible container is made of soft polyvinyl chloride, vinylidene chloride, nylon or polyurethane material.

In at least one embodiment, the flexible container includes an inlet-side flexible container and an outlet-side flexible container, and the inlet-side flexible container is formed with a blood inlet for introducing blood to be filtered.

In at least one embodiment, the outlet-side flexible container is formed with a blood outlet for discharging the blood filtered by the filter element.

By adopting the above technical solution, the present invention provides a blood treatment filter, wherein the filter element and the flexible container are melted by making the filter element at least include an inlet-side filter layer, an intermediate filter layer and an outlet-side filter layer arranged in layers. Mixing to form a composite material layer can effectively improve the centrifugation resistance of the blood processing filter.

Description of drawings

FIG. 1 shows a schematic structural diagram of a blood processing filter according to the present invention.

FIG. 2 shows a schematic diagram representing the effective filtration area when evaluating centrifugation resistance.

FIG. 3 is a partial enlarged view of FIG. 2 showing a corner portion of the effective filtering area.

Description of reference numerals

1 flexible container; 11 inlet side flexible container; 111 blood inlet; 12 outlet side flexible container; 13 first sealing part; 14 second sealing part;

2 filter element; 21 inlet side filter layer; 22 middle filter layer; 23 outlet side filter layer.

Detailed ways

Exemplary embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that these specific descriptions are only used to teach those skilled in the art how to implement the present invention, and are not used to exhaust all possible ways of the present invention, nor are they used to limit the protection scope of the present invention.

The specific embodiment of the blood processing filter according to the present invention will be described in detail below with reference to FIG. 1 .

In this embodiment, as shown in FIG. 1 , the blood treatment filter includes a flexible container 1 and a filter element 2 . Therein, the flexible container 1 clamps the filter element 2 and is sealed.

In the present embodiment, as shown in FIG. 1 , the flexible container 1 includes an inlet-side flexible container 11 and an outlet-side flexible container 12 . The inlet-side flexible container 11 and the outlet-side flexible container 12 sandwich the filter element 2 .

A blood inlet 111 is formed on the inlet-side flexible container 11, and the blood inlet 111 is used to introduce blood to be filtered. The outlet-side flexible container 12 is formed with a blood outlet for discharging the blood filtered by the filter element 2 .

The inlet-side flexible container 11 and the outlet-side flexible container 12 are sealed by the first sealing portion 13 and the second sealing portion 14 . The first sealing portion 13 is formed into an annular band shape by welding the flexible container 1 and the filter element 2 to perform preliminary sealing of the blood treatment filter. The second sealing portion 14 is formed on the outer side of the first sealing portion 13 so as to surround the first sealing portion 13 , and is formed by welding the flexible container 1 .

In this embodiment, as shown in FIG. 1 , the filter element 2 includes an inlet-side filter layer 21 , an intermediate filter layer 22 , and an outlet-side filter layer 23 that are stacked. The inlet-side filter layer 21 and the outlet-side filter layer 23 are made of polyethylene terephthalate, and the middle filter layer 22 is made of polybutylene terephthalate.

In this embodiment, the inlet-side flexible container 11, the inlet-side filter layer 21 and the intermediate filter layer 22 are melt-mixed to form the first composite material layer. The intermediate filter layer 22, the outlet-side filter layer 23 and the outlet-side flexible container 12 are melt-mixed to form a second composite material layer. In this way, the multi-layered filter element 2 and the flexible container 1 are melt-mixed to form a composite material layer, and the physical structure of the composite material layer is complicated. Even if there is no adhesiveness between the flexible container 1 and the filter element 2, the flexible container 1 and the The filter elements 2 are also not easily peeled off, that is, the peeling resistance and centrifugation resistance of the entire blood processing filter are improved.

In this embodiment, the composite material layer can be formed by: after laminating the materials (the flexible container 1 and the filter element 2), sandwiching them in a mold for high-frequency welding, pressing under a certain pressure, and then applying high frequency. The flexible container 1 heated by high-frequency waves softens and melts, and enters into the voids of the fibers of the inlet-side filter layer 21 and the outlet-side filter layer 23 under the action of a suitable punching pressure (the inlet-side filter layer 21 and the outlet-side filter layer 23 should be with a suitable aperture to allow the molten flexible container 1 to enter). At this time, since the inlet side filter layer 21 and the outlet side filter layer 23 are not heated to the temperature at which the fibers are melted, and have a higher melting point than the flexible container 1, the fibers of the inlet side filter layer 21 and the outlet side filter layer 23 remain Instead of melting, the flexible container 1 is melted in the gap, and then melt-mixed with the inlet-side filter layer 21 and the outlet-side filter layer 23 to form a composite material layer. On the other hand, the temperature of the intermediate filter layer 22 starts to rise from the approximate center in the thickness direction, the intermediate filter layer 22 near the center reaches the melting point by high-frequency heating, and enters the intermediate filter layer from above and below the flexible container 1 The melting starts earlier before 22 and then melts and diffuses until it encounters the composite layer described above. Finally, after stopping the high frequency application, the composite layer is completed by a cooling step. It can be understood that the welded product of the present application can be obtained by selecting an appropriate structure and material of the filter element 1 and setting appropriate welding conditions and stamping pressure.

In this embodiment, the flexible container 1 can be exemplified by: soft polyvinyl chloride, vinylidene chloride, nylon, polyurethane, ethylene-vinyl acetate copolymer, styrene-butadiene-styrene copolymer Thermoplastic elastomers of hydrogenated products, styrene-isoprene copolymers or their hydrogenated products, etc., and mixtures of thermoplastic elastomers and softeners such as polyolefins, ethyl acrylate, etc. A film-like molded product. Among them, soft polyvinyl chloride, vinylidene chloride, nylon or polyurethane is the preferred material, and soft polyvinyl chloride is the best material.

In this embodiment, the fiber diameters or pore sizes of the layers in the filter element 2 may vary. In the thickness direction of the filter element 2, the fiber diameter or pore size of the filter element 2 gradually or continuously decreases from the portion of the filter element 2 in contact with the flexible container 1. For example, the fiber diameter or pore size of the inlet side filter layer 21 may be larger than that of the intermediate filter layer 22 , and the fiber diameter or pore size of the outlet side filter layer 23 may be larger than that of the intermediate filter layer 22 .

The centrifugation resistance of the present invention will be described. Here, the centrifugation resistance refers to the present invention having centrifugation resistance by subjecting a blood processing filter of a flexible container to a centrifugation process using a centrifuge for the purpose of component separation. The utility model is a filter capable of withstanding the centrifugation. Specifically, it is a flexible blood processing filter capable of preventing the occurrence of cracks in the first sealing portion 13 and leakage of blood to the outside.

The evaluation method for centrifugation resistance will be described in detail below.

The blood processing filter after steam heating sterilization is housed in a centrifuge (manufactured by Hitachi Koki Co., Ltd., model specification: CR7N) together with the blood bag. The connected blood processing filter is folded together with the blood bag and the blood flow path, and is accommodated in one centrifuge cup of the centrifuge. In addition, centrifugation was performed under the following conditions so that the weight of the centrifuge cup on the opposite side was as equal as possible.

That is, set the rotation speed (g·sec) to 5000g·sec, the time to be 19 minutes, the acceleration time from 0 to 500rpm to be 2 minutes, the deceleration time from 500 to 0rpm to be 4 minutes, and the temperature to be 22°C. The operation timer (Actualruntimer) is disabled, that is, the set time is counted immediately after the start of centrifugation.

After the centrifugation, it was checked whether or not cracks had occurred in the first sealing portion. Specifically, using a syringe, inject ink (flag brand ink (for sol ink pads) red) into the blood inlet 111 of the filter for the centrifugal test in an amount equal to the effective filtration area per 1 cm ² of the blood processing filter ( To be described later) 0.80 ml of ink was injected, and 1 hour after injection, it was confirmed whether or not the ink leaked to the first sealing portion 13 .

As schematically shown in FIG. 2 , the effective filtering area is the area obtained by subtracting the partial areas of the four corners from the product of the vertical length and the horizontal length. Specifically, as shown in an enlarged manner in FIG. 3 , for a corner, the rounded portion of the corner is regarded as an effective filtering area, and therefore, based on the radius of the rounded portion, the effective filtering area in the present application is calculated, that is, , and the effective filtering area (cm ² ) is the vertical length of the filter×horizontal length −{4(radius of R part) ² −((radius of R part) ² ×π)}. In addition, the effective filtration area refers to the area of the filter element actually used for blood filtration, and is the area inside the first sealing portion. Therefore, the calculation formula of the effective filtering area is not limited to this formula.

Thus, whether or not the desired centrifugation resistance is obtained is evaluated based on whether or not ink leaks to the first sealing portion 13 .

By adopting the above technical solutions, the blood processing filter according to the present invention has at least the following advantages:

In the blood treatment filter of the present invention, by making the filter element at least include the inlet side filter layer, the middle filter layer and the outlet side filter layer arranged in layers, the filter element and the flexible container are melted and mixed to form the composite material layer, which can effectively Improved strip resistance and centrifugation resistance of blood processing filters.

The above specific embodiment has described the technical scheme of the present utility model in detail, but also needs to be supplemented:

(1) Although the filter element is described as including the inlet side filter layer, the middle filter layer and the outlet side filter layer in the above embodiment, the present invention is not limited to this, and the filter element may also include more filter layers.

(2) In the above-mentioned embodiment, the first composite material layer and the second composite material layer do not necessarily exist at the same time, and the peeling resistance and resistance of the blood treatment filter can be improved as long as one of the two composite material layers is formed. Centrifugal. In addition, the first composite material layer may be formed by melt-mixing only the inlet-side filter layer and the inlet-side flexible container, and the second composite material layer may be formed by melt-mixing only the outlet-side filter layer and the outlet-side flexible container.

(3) Although the above-mentioned embodiments describe that the fiber diameters or pore sizes of the layers in the filter element may be different, the present invention is not limited to this, and the fiber diameters or pore sizes of the layers in the filter element may be the same.

Claims (10)

1. A blood treatment filter, characterized in that it comprises a flexible container (1) and a filter element (2),

the flexible container (1) clamps the filter element (2) and is sealed,

the filter element (2) comprises at least an inlet-side filter layer (21), an intermediate filter layer (22), and an outlet-side filter layer (23) that are arranged in layers, the inlet-side filter layer (21) and the outlet-side filter layer (23) being made of polyethylene terephthalate, the intermediate filter layer (22) being made of polybutylene terephthalate,

the flexible container (1) is melt mixed with the filter element (2) to form a composite layer.

2. A blood treatment filter according to claim 1, wherein the blood treatment filter comprises a first sealing portion (13), the first sealing portion (13) being formed into an annular band shape by welding the flexible container (1) and the filter element (2).

3. A blood treatment filter according to claim 2, wherein the blood treatment filter comprises a second sealing portion (14), the second sealing portion (14) being formed on the outside thereof in such a manner as to surround the first sealing portion (13), by welding the flexible container (1).

4. A blood treatment filter according to claim 1, wherein the flexible container (1) comprises an inlet side flexible container (11) and an outlet side flexible container (12), the inlet side flexible container (11), the inlet side filter layer (21) and the intermediate filter layer (22) being melt-mixed to form a first composite material layer.

5. A blood treatment filter according to claim 1, wherein the flexible container (1) comprises an inlet side flexible container (11) and an outlet side flexible container (12), the intermediate filter layer (22), the outlet side filter layer (23) and the outlet side flexible container (12) being melt-mixed to form a second composite material layer.

6. A blood treatment filter according to claim 1, wherein the fiber diameter or pore size of the filter element (2) decreases stepwise or continuously from a portion of the filter element (2) contacting the flexible container (1) in the thickness direction of the filter element (2).

7. A blood treatment filter according to claim 6, wherein the fiber diameter or pore size of the inlet-side filtration layer (21) is larger than that of the intermediate filtration layer (22), and the fiber diameter or pore size of the outlet-side filtration layer (23) is larger than that of the intermediate filtration layer (22).

8. A blood treatment filter according to claim 1, wherein the flexible container (1) is made of a soft polyvinyl chloride, vinylidene chloride, nylon or polyurethane material.

9. A blood treatment filter according to claim 1, wherein the flexible container (1) comprises an inlet side flexible container (11) and an outlet side flexible container (12), the inlet side flexible container (11) having a blood inlet (111) formed thereon, the blood inlet (111) being for introducing blood to be filtered.

10. A blood treatment filter according to claim 9, wherein the outlet side flexible container (12) is formed with a blood outlet for discharging blood filtered by the filter element (2).

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