HK1119096B - Blood filter device and method of manufacturing the same - Google Patents

Description

Blood filter device and method for manufacturing same

Technical Field

The present invention relates to a blood filtration device for filtering foreign matter, thrombus, and the like in an artificial heart-lung circuit. In particular, the present invention relates to a blood filtration device having a structure for easily removing air bubbles accumulated in a filter, and a method for manufacturing the same.

Background

In many cases, a blood filtration device such as an arterial filter is incorporated into an artificial heart-lung circuit used in a cardiac operation involving extracorporeal circulation, in view of safety. As a performance required for such a blood filtration device, from the viewpoint of ensuring safety of a patient, there is a strong demand for a structure designed to exclude minute foreign substances in an artificial heart-lung circuit, thrombus generated during surgery, or air mixed into or separated from the circuit so that these substances are not sent into the patient.

Generally, a polyester wire mesh filter of about 20 to 40 μm is used in a cylindrical pleated shape. For example, as shown in patent document 1, a sheet-like filter medium is folded in a plurality of pleats, radially formed into a cylindrical shape with the crests of the pleats on the outer side and the troughs on the inner side, and attached to a cylindrical casing. According to this filter, blood flows in the radial direction of the cylindrical filter medium in the housing, and the blood can be effectively removed of garbage, impurities, thrombus, and the like in the blood through the filter medium.

In the above filter, blood flows into the upper portion of the cylindrical filter medium, passes through the filter medium in the radial direction via the outer portion of the cylindrical filter medium, passes through the inside of the cylindrical filter medium, and then flows out from the lower portion. Since the surface of the filter medium is arranged in the vertical direction, bubbles are likely to remain in the filter when the flow of the filling liquid flows onto the filter surface at the time of start-up. Moreover, it is difficult to release such remaining bubbles to the outside. This is because, since the filter surface is arranged in the vertical direction, it is difficult for the bubbles to leave the filter, and it takes a considerable time to completely remove the bubbles.

That is, the residual air bubbles inside the filter are separated by an impact from the outside, such as knocking the housing with a finger. In this case, even if an impact is applied from the front of the bubble adhesion portion, although the bubbles are once separated from the filter, the bubbles are likely to adhere again to the pleated portion of the adjacent filter, and it is difficult to guide the bubbles to the exhaust port located above.

In order to solve this problem, patent document 2 describes a blood filtration device having a structure capable of effectively removing impurities, thrombus, and the like in blood and easily removing air bubbles remaining in a filter.

In the blood filtration device described in patent document 2, the housing is formed of a dome provided with a blood inlet and an air outlet at the top, a filter holding portion disposed at the bottom of the dome, and a bottom portion disposed at the bottom of the filter holding portion and provided with a blood outlet. Blood that has flowed into the dome from the inflow port flows out from the outflow port via the filter holding portion. The filter is disposed in the filter holding portion so as to partition the inner cavity of the housing into a dome side and a bottom side. The filter has a shape formed by folding a sheet-like filter medium so as to form a plurality of pleats, and is disposed so that ridge lines of the plurality of pleats cross the inner cavity of the filter holding portion in parallel with each other.

According to this configuration, foreign matter, thrombus, and the like in blood can be reliably eliminated, and since there is no obstacle in the vertical direction of the filter, bubbles adhering to the upper surface of the filter during the start-up operation can be easily removed only by giving physical impact to the housing.

Patent document 1: japanese patent No. 3270193

Patent document 2: international publication WO2004/084974 Specification

The filter having a shape in which the plurality of pleats are arranged in parallel as described above is preferably held in the filter holding portion with a certain gap between adjacent pleats. In a state where the pleats are in contact with each other without a gap, since a closed space is formed inside the recesses between the pleats, when air bubbles remain in the closed space or air bubbles generated at other positions are trapped, it is difficult to remove the air bubbles even if physical impact is applied to the housing.

However, it is difficult to fix the filter in the cavity of the filter holder while maintaining a gap between adjacent pleats. That is, when the filter folded with the pleats formed is disposed in the filter holding portion, since the sheet-like filter medium constituting the filter is in a free state, the pleats expand in shape, and adjacent pleats are likely to come into contact with each other. This can be an obstacle especially when one wants to improve the filtering effect without enlarging the filter housing. That is, when the pleat height is increased and the pitch is decreased in order to increase the filter membrane area, the pleats are likely to be in contact with each other due to natural expansion.

Disclosure of Invention

Accordingly, an object of the present invention is to provide a blood filtration device having a structure capable of securing a gap between a plurality of pleats of a sheet-like filter medium constituting a filter, in order to facilitate removal of air bubbles.

The blood filter device of the present invention includes a housing having a dome provided with a blood inlet and forming an upper structure, a filter holding portion forming a central structure of a lower portion of the dome, and a bottom portion disposed at a lower portion of the filter holding portion and provided with a blood outlet, and a filter attached to a cavity of the filter holding portion and dividing the cavity of the housing into a dome side and a bottom side. The filter is formed by folding a sheet-like filter medium so as to form a plurality of pleats, and is disposed so that ridge lines of the plurality of pleats cross the inner cavity of the filter holding section in parallel with each other.

In order to solve the above problem, a blood filtration device according to the present invention includes: an annular holder disposed between an inner peripheral surface of the filter holding portion and an outer peripheral surface of the filter; an annular ridge substrate that is an annular member disposed so as to face ridge lines of the plurality of pleats in an outer peripheral region of the filter, and that is provided with a plurality of ridges each entering between the ridge lines of the plurality of pleats; and a bonding resin which is filled in an outer peripheral portion of the filter including the annular holder and the annular ridge substrate and bonds the outer peripheral portion of the filter to the filter holding portion.

A method for manufacturing a blood filtration device according to the present invention is a method for manufacturing a blood filtration device, including: a filter structure in which the filter, the annular holder, and the annular rib base plate are combined, the filter being attached to an annular holder which can be formed between an inner peripheral surface of the filter holder and an outer peripheral surface of the filter so that an outer peripheral surface of the annular holder faces the inner peripheral surface of the annular holder, and the annular rib base plate being an annular member having a shape and a size which can face ridge lines of the plurality of pleats in an outer peripheral region of the filter, and being provided with a plurality of ribs which can be inserted between the ridge lines of the plurality of pleats, respectively, and the annular rib base plate being attached to the filter so that the plurality of ribs are inserted between the ridge lines of the plurality of pleats, respectively, and the filter structure being attached to the housing so as to be positioned in an inner cavity of the filter holder, the outer peripheral portion of the filter including the annular holder and the annular ridge substrate is filled with a bonding resin and cured, and the filter is bonded to the filter holding portion with the bonding resin.

According to the blood filter device having the above-described configuration, the plurality of ribs provided on the annular rib substrate enter between the ridge lines of the plurality of pleats, respectively, and therefore, a gap can be secured between the plurality of pleats of the filter. This makes it possible to easily remove air bubbles remaining in the filter or air bubbles trapped in the filter.

Drawings

Fig. 1A is a front view of a blood filtration device according to an embodiment of the present invention.

FIG. 1B is a top view of the same blood filtration device.

FIG. 1C is a cross-sectional view of the same blood filtration device.

Fig. 2 is a perspective view of a filter constituting the same blood filtration device.

Fig. 3 is a perspective view of a filter structure constituting the same blood filtration device.

Fig. 4 is a perspective view of a ring holder constituting the same blood filtration device.

Fig. 5A is a plan view of the same annular holder.

Fig. 5B is a sectional view of the same annular holder.

Fig. 6 is a perspective view of an annular rib substrate constituting the same blood filtration device.

Fig. 7A is a top view of the same annular prism substrate.

Fig. 7B is a front view of the same annular prism substrate.

FIG. 8A is a sectional view showing the upper half of the housing constituting the same blood filtration device.

Fig. 8B is a bottom view of the same housing upper half.

Fig. 9A is a plan view showing the same lower half of the housing.

Fig. 9B is a cross-sectional view of the same lower housing half.

Fig. 10 is a perspective view showing one step of a method of manufacturing a blood filtration device according to an embodiment of the present invention.

Fig. 11 is a plan view showing another step of the same manufacturing method.

Fig. 12 is a perspective view showing another step of the same manufacturing method.

Fig. 13 is a sectional view showing an apparatus used for potting in the same manufacturing method.

Description of the symbols

1 outer cover

1a upper half of the casing

1b lower half body of shell

2 dome

3 Filter holder

3a holding part inner cylinder

3b holding part outer cylinder

4 bottom

4a support part

5 blood inflow port

6 air outlet

7 blood outflow port

8 Filter

8a sheet-like filter medium

8b fold

8c fold gap

9 Ring-shaped holder

9a cylinder part

9b flange part

10 annular edge substrate

10a ring part

10b edge

10c fold receiving part

11 bonding resin

12 Filter Structure

13 auxiliary bonding resin

14 cuts

15 through hole

16 rotating clamp

16a inner cavity

17 resin reservoir

18 resin supply path

Detailed Description

In the blood filtration device according to the present invention, it is preferable that the outer peripheral edge of the filter is bonded to the inner peripheral surface of the annular holder with auxiliary bonding resin, and further bonded to the filter holding portion with the bonding resin.

Preferably, the filter further includes a pair of annular rib substrates, and each of the annular rib substrates is disposed to face a rib line of the plurality of pleats on both upper and lower surfaces of the filter.

In the method of manufacturing a blood filtration device according to the present invention, it is preferable that after the filter is mounted on the annular holder, an outer peripheral edge of the filter is filled with an auxiliary bonding resin, whereby the outer peripheral edge of the filter is held on an inner peripheral surface of the annular holder by the auxiliary bonding resin.

Further, it is preferable that after the filter structure is mounted in the housing, the bonding resin is filled in an outer peripheral region of the filter including the annular holder and the annular rib base plate while a centrifugal force is applied to a periphery of a central portion of the cavity of the filter holding portion.

The blood filtration device according to the embodiment of the present invention will be described below with reference to the drawings.

Fig. 1A is a front view, fig. 1B is a plan view, and fig. 1C is a sectional view of the blood filtration device. The housing 1 is made of, for example, resin, and has a dome 2 forming an upper structure, a filter holding portion 3 forming a central structure, and a bottom portion 4 forming a lower structure. The cross-section of the housing 1 is circular in shape.

A blood inflow port 5 is provided in a side surface portion of the dome 2 so that blood flows in a horizontal direction and in a direction along an inner wall of the dome 2. The top of the dome 2 is provided with an air discharge port 6 for discharging air such as bubbles. A blood outflow opening 7 is provided in the bottom 4. The filter holding portion 3 is formed in a cylindrical shape. As shown in fig. 1C, a filter 8 for filtering foreign substances in blood is disposed in the filter holding portion 3. The filter 8 partitions the inner cavity of the housing 1 into a dome 2 side and a bottom 4 side. The liquid flowing into the dome 2 from the blood inlet 5 flows out from the blood outlet 7 via the filter holding portion 3. The bottom portion 4 is formed with a support portion 4a, but the support portion 4a is a portion used when the filter device is provided, and is not related to the filtering function.

The dome 2 has a shape with an inner diameter gradually decreasing toward the upper side. This makes it easy for the bubbles to rise along the inner peripheral surface of the dome 2 while being concentrated. The dome 2 has a circular cross section, and a blood inlet 5 is provided to allow blood to flow in a horizontal direction and along the inner wall of the dome 2. The blood flowing in from the blood inlet 5 flows downward and flows into the filter holding portion 3. The dome 2 may have a shape other than the shape shown in fig. 1A and the like, as long as the outer diameter thereof gradually decreases toward the air outlet 6. For example, a conical shape or a funnel shape may also be used.

As shown in fig. 1C, the housing 1 is composed of an upper housing half 1a and a lower housing half 1 b. The filter holder 3 is composed of a holder inner tube 3a and a holder outer tube 3b formed on the case upper half 1a and the case lower half 1b, respectively. The outer shell 1 is integrated by fitting the upper outer shell half 1a and the lower outer shell half 1b into the inner holding portion cylinder 3a and the outer holding portion cylinder 3 b.

As conceptually shown in fig. 2, the filter 8 has a shape obtained by folding a sheet-like filter medium 8a made of a sheet-like net so as to form a plurality of pleats. The filter 8 is disposed such that ridge lines 8b of a plurality of pleats cross the inner cavity of the holding portion inner tube 3a (filter holding portion 3) in parallel with each other. That is, the ridge line 8b of each fold is arranged in the chord direction of the holding section inner tube 3a in parallel with the direction of the blood inlet 5 or the blood outlet 7. Since the envelope surface of the ridge line 8b of each pleat is flat, the filter 8 as a whole has a flat plate-like outer shape. Since the ridge line 8b of each pleat is arranged parallel to the direction of the blood inlet 5 or the blood outlet 7, the flow direction of blood or priming liquid is parallel to the ridge line 8b of the pleat, and therefore these liquids easily flow into the space between the pleats. This also ensures removal of bubbles.

As shown in fig. 1C, the annular holder 9 is disposed between the inner peripheral surface of the filter holding portion 3 and the outer peripheral surface of the filter 8. The annular ridge substrate 10 is disposed to face the ridge line 8b of the plurality of pleats of the filter 8 in the outer peripheral region of the filter 8. The annular ridge substrate 10 has a plurality of ridges (not shown in fig. 1C) that respectively enter between ridge lines 8b of the plurality of wrinkles, as will be described later. The outer periphery of the filter 8 including the annular holder 9 and the annular rib substrate 10 is filled with a bonding resin 11. The filter 8 is bonded to the inner peripheral surface of the annular holder 9 with an auxiliary bonding resin (not shown), and further bonded to the inner peripheral surface of the filter holder 3, that is, the inner peripheral surface of the holder inner tube 3a with a bonding resin 11.

Fig. 3 shows a filter structure 12 obtained by combining the filter 8, the annular holder 9, and the annular rib substrate 10. The outer peripheral edge of the filter 8 is bonded to the inner peripheral surface of the annular holder 9 with an auxiliary bonding resin 13.

Fig. 4, 5A, and 5B show the structure of the ring holder 9. Fig. 4 is a perspective view of the ring holder 9, fig. 5A is a plan view thereof, and fig. 5B is a sectional view taken along line a-a of fig. 5A. The annular holder 9 is composed of a cylindrical portion 9a and a flange portion 9 b. The cylindrical portion 9a provides an inner space in which the filter 8 is mounted and an inner circumferential surface for engaging the outer circumferential surface of the filter 8. The flange portion 9b can hold the annular holder 9 when the filter 8 and the annular ridge base plate 10 are mounted, and provides convenience in handling when the filter structure 12 is mounted in the filter holding portion 3.

Fig. 6, 7A, and 7B show the structure of the annular ridge substrate 10. Fig. 6 is a perspective view, fig. 7A is a plan view, and fig. 7B is a front view of the annular ridge substrate 10. The annular rib substrate 10 includes a disc-shaped annular portion 10a and a plurality of ribs 10 b. The plurality of ribs 10b are arranged on the surface of the annular portion 10a, and a pair of upper and lower eggplant-shaped ribs 10b in fig. 7A correspond to the space between the ridge lines 8b of the pleats of the filter 8. Therefore, the wrinkle receiving portion 10c formed by the gap between the adjacent ridges 10 corresponds to the ridge line 8b of each wrinkle. In the filter structure 12 shown in fig. 3, the ridge lines 8b of the pleats are inserted into the pleat receiving portions 10c, respectively.

As shown in fig. 3, by attaching the annular rib substrate 10, the interval between the sheet-like filter media 8a forming each pleat is wider than the ribs 10b in the peripheral edge region of the filter 8, thereby forming pleat gaps 8 c.

The filter structure 12 configured as described above is attached to the filter holding portion 3 as shown in fig. 1C, and is joined by the joining resin 11, thereby configuring the blood filtration device of the present embodiment.

In the blood filtration device of the present embodiment configured as described above, as shown in fig. 3, by forming the pleat gaps 8c in the peripheral edge region of the filter 8, air bubbles and the like remaining between the pleats of the filter 8 are easily removed upward through the pleat gaps 8 c. When the blood or the priming solution flowing in from the blood inlet 5 passes through the filter 8 of the filter holding portion 3, the blood or the priming solution flows in from the pleat gaps 8c in the peripheral edge region and smoothly flows between the pleats, and bubbles can be easily removed by this flow. Further, the interval between the sheet-like filter media 8a may be expanded by the first inflow of the liquid flow, and the pleat gap may be formed up to the central region of the filter 8, thereby expanding the flow path of the priming liquid. Therefore, the annular rib substrate 10 can provide a sufficient function for removing bubbles remaining or trapped in the filter 8 by forming the pleat gaps 8c at least in the peripheral edge region of the filter 8.

Further, by mounting the annular ridge substrate 10 at least on the upper surface of the filter 8, a practically sufficient effect can be obtained. When a pair of annular rib substrates 10 are provided and mounted on the upper and lower surfaces of the filter 8, respectively, bubbles can be removed more easily.

As the filter medium, a mesh-like filter medium, woven fabric, nonwoven fabric, or the like, or a combination thereof, or the like can be used. As the material, polyester, polypropylene, polyamide, fluorine fiber, stainless steel, or the like can be used.

The cross-sectional shape of the housing 1, particularly the dome 2, is preferably circular, but the same effect as described above can be obtained by using other shapes such as an oval shape.

Next, a method for manufacturing the filter device of the present embodiment will be described. Fig. 8A is a sectional view showing the upper case half 1a constituting the blood filtration device, and fig. 8B is a bottom view thereof. Fig. 9A is a plan view showing the lower case half 1B, and fig. 9B is a sectional view thereof.

The basic structure is as described with reference to fig. 1A to 1C. A pair of notches 14 are formed in the holding portion inner tube 3a of the housing upper half 1 a. A through hole 15 is formed in the holding portion outer cylinder 3b of the case lower half 1b at a position corresponding to the pair of notches 14 of the holding portion inner cylinder 3 a. When the upper and lower case half bodies 1a, 1b are fitted to each other, the notch 14 and the through hole 15 communicate with each other, and a hole is formed to penetrate the peripheral wall of the inner and outer tubes 3a, 3b of the holding portion. The hole is used as a resin passage for filling resin in potting described later.

Fig. 10, 11, and 12 show steps related to the production of the filter structure in the production of the blood filtration device.

First, as shown in fig. 10, the filter 8 is attached to the annular holder 9. Next, as shown in fig. 11, the auxiliary bonding resin 13 is filled and cured between the outer peripheral edge of the filter 8 and the inner peripheral surface of the annular holder 9. As shown in the drawing, the auxiliary bonding resin 13 is filled in each peripheral edge portion of the filter 8, thereby bonding the filter 8 to the annular holder 9. Fig. 11 is a view seen from the front side, and the auxiliary bonding resin 13 is similarly filled in the respective peripheral portions of the filter 8 on the back side. Next, as shown in fig. 12, the pair of annular rib substrates 10 are opposed to the upper and lower surfaces of the filter 8, respectively. And then installed such that the plurality of ribs 10b enter between the plurality of pleated ribs of the filter 8, respectively. As a result, as shown in fig. 3, a filter structure 12 is formed by combining the filter 8, the annular holder 9, and the annular rib substrate 10.

In the step of attaching the annular rib substrate 10 to the filter 8 by forming the filter structure 12 as described above, the operation of inserting each of the plurality of ribs 10b between the ridge lines of the plurality of pleats can be performed extremely easily. This is because, in the step shown in fig. 11, the operation of attaching the annular ridge substrate 10 is performed in a state where the filter 8 is attached to the annular holder 9 and bonded with the auxiliary bonding resin 13 so that the filter 8 is held in a predetermined shape. As a result, the pleat gap 8c can be reliably and easily formed in the peripheral edge region of the filter 8.

Next, in order to manufacture the blood filtration device, the filter structure 12 formed as described above is attached to the holding portion inner tube 3a of the housing upper half 1a shown in fig. 8A and 8B. Then, the outer case 1 is integrated by fitting the holding portion outer cylinder 3B of the lower case half 1B shown in fig. 9A and 9B to the holding portion inner cylinder 3 a. Next, the housing 1 to which the filter structure 12 is attached is set in an apparatus having the potting jig shown in fig. 13, and potting with a sealing resin is performed.

The apparatus shown in fig. 13 is composed of a rotary jig 16, a resin reservoir 17, and a resin supply path 18. The rotary jig 16 has an inner cavity 16a having a predetermined shape for supporting the housing 1. A resin reservoir 17 for storing a sealing resin such as urethane resin is provided at an upper portion of the rotary jig 16, and a resin supply passage 18 is formed from the resin reservoir 17 to a side surface of the filter holding portion 3. The housing 1 is provided in the rotary jig 16, and the rotary jig 16 is rotated, whereby the housing 1 is rotated together. The sealing resin supplied to the side surface of the filter holding portion 3 enters the cavity of the holding portion inner tube 3a through the notch 14 and the through hole 15 (see fig. 8A, 8B, 9A, and 9B).

When the rotary jig 16 is rotated, a centrifugal force in the horizontal direction acts around the axial center of the filter holding portion 3. Thereby, the sealing resin overflows from the resin reservoir 17, and is supplied into the holding portion inner cylinder 3a via the resin supply passage 18, and the resin is filled between the inner circumferential surface of the holding portion inner cylinder 3a and the outer circumferential portion of the filter 8. By curing the filled resin, as shown in fig. 1C, the filter 8, the annular holder 9, and the annular ridge substrate 10 can be held on the inner peripheral surface of the holding portion inner tube 3a by the bonding resin 11.

The range of the resin filling is adjusted with reference to the inner peripheral edge of the annular rib substrate 10. The inner peripheral edge of the annular ridge base 10 is set so as to match the diameter of the lower end of the inner peripheral surface of the dome 2 and the diameter of the upper end of the inner peripheral surface of the bottom 4. Therefore, the flow path in the filter 8 defined by the joining resin 11 is smoothly connected with the lower end of the inner peripheral surface of the dome 2 and the upper end of the inner peripheral surface of the bottom 4, thereby obtaining a good flow path state.

The blood filtration device of the present invention can easily remove air bubbles remaining or trapped in the filter, and is therefore useful for constructing an artificial heart-lung circuit.

Claims (4)

1. A blood filtration device is provided with:

a housing having a dome provided with a blood inflow port and forming an upper structure, a filter holding portion forming a central structure of a lower portion of the dome, and a bottom portion disposed at a lower portion of the filter holding portion and provided with a blood outflow port; and

a filter installed in the inner cavity of the filter holding part and dividing the inner cavity of the housing into a dome side and a bottom side,

the blood filtration device is characterized in that the filter is formed by folding a sheet-like filter medium so as to form a plurality of pleats, and is disposed so that ridge lines of the plurality of pleats are parallel to each other and cross the lumen of the filter holding section, and the blood filtration device is provided with:

an annular holder disposed between an inner peripheral surface of the filter holding portion and an outer peripheral surface of the filter;

an auxiliary bonding resin for bonding the outer periphery of the filter to the inner peripheral surface of the annular holder;

an annular ridge substrate that is an annular member disposed so as to face ridge lines of the plurality of pleats in an outer peripheral region of the filter, and that is provided with a plurality of ridges that respectively enter between the ridge lines of the plurality of pleats;

and a bonding resin which is filled in an outer peripheral portion of the filter including the annular holder and the annular ridge substrate and bonds the outer peripheral portion of the filter to the filter holding portion.

2. The blood filtration device according to claim 1, comprising a pair of the annular ridge base plates, and each of the annular ridge base plates is disposed so as to face a ridge line of the plurality of pleats on both the upper and lower surfaces of the filter.

3. A method for manufacturing a blood filtration device, the method comprising:

a housing having a dome provided with a blood inflow port and forming an upper structure, a filter holding portion forming a central structure of a lower portion of the dome, and a bottom portion disposed at a lower portion of the filter holding portion and provided with a blood outflow port; and

a filter installed in the inner cavity of the filter holding part and dividing the inner cavity of the housing into a dome side and a bottom side,

the filter is formed by folding a sheet-like filter medium so as to form a plurality of pleats, and is disposed so that ridge lines of the plurality of pleats are parallel to each other and cross an inner cavity of the filter holding section, and the manufacturing method is characterized by comprising:

the filter is mounted on an annular holder which can be formed between the inner peripheral surface of the filter holder and the outer peripheral surface of the filter so that the outer peripheral surface of the filter faces the inner peripheral surface of the annular holder,

an outer peripheral edge of the filter is held on an inner peripheral surface of the annular holder by an auxiliary bonding resin filled in the outer peripheral edge of the filter,

a filter structure in which the filter, the annular holder, and the annular ridge substrate are combined to form the filter structure, wherein the annular ridge substrate is an annular member having a shape and a size capable of facing ridge lines of the plurality of pleats in an outer peripheral region of the filter, and is provided with a plurality of ridges capable of entering between the ridge lines of the plurality of pleats, and the annular ridge substrate is attached to the filter such that the plurality of ridges enter between the ridge lines of the plurality of pleats,

mounting the filter structure within the housing so as to be located within the internal cavity of the filter holder,

the outer peripheral portion of the filter including the annular holder and the annular ridge substrate is filled with a bonding resin and cured, and the filter is bonded to the filter holding portion with the bonding resin.

4. The method of manufacturing a blood filtration device according to claim 3, wherein the bonding resin is filled in an outer peripheral region of the filter including the annular holder and the annular rib substrate, while a centrifugal force is applied around a central portion of the cavity of the filter holding portion after the filter structure is mounted in the housing.