Medical filter unit and its manufacturing method, and filter unit for reusable masks and reusable mask using the same

Abstract

For example, to provide a medical filter unit with a novel structure that has excellent collection performance against viruses, etc., and to provide a filter unit for a reusable mask with a novel structure that allows high-performance filter components to be reused. [Solution] A medical filter unit 10 is provided in which a filter member 12 equipped with a filter sheet 16 is housed in a cylindrical frame 30 provided on a resin support 14 attached to a main body member 48. The filter sheet 16 is folded back to form a pleated shape with multiple peaks and valleys. The first end edges 22, 22 of the filter sheet 16 on both sides in the direction of continuity of the peaks and valleys, and the second end edges 24, 24 of the filter sheet 16 extending in a zigzag pattern on both sides in the width direction of the peaks and valleys are each fixed to the frame 30 in an embedded state along their entire length, so that the entire circumference of the filter sheet 16 is fixed to the frame 30 in an embedded state.

Description

Technical Field

[0001] The present invention relates to a medical filter unit used for infection prevention and the like, a filter unit for a reusable mask, and the like.

Background Art

[0002] Conventionally, masks used to prevent inhalation of particles in the air during breathing are known. Among them, the filter member of a medical mask worn by medical staff for the purpose of preventing infection by breathing, etc., is required to have the performance of collecting minute objects such as viruses. Therefore, products have been put on the market that improve the collection efficiency of viruses and the like by adopting a filter member having a laminated structure in which a plurality of filter sheets are stacked together. On the other hand, as a patent document, for example, as disclosed in Japanese Patent Translation Laid-Open No. 2020-506734 (Patent Document 1), there is also a structure in which a filter unit provided with a pleated filter member for collecting particles is attached to a solid body worn on the user's face. The filter unit of Patent Document 1 has a structure in which a flexible frame as a frame portion is integrally fixed around the filter member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, a medical mask provided with a filter member having a high collection efficiency due to a laminated structure has a new problem that its air permeability is reduced and the user feels short of breath, so it is difficult to wear it for a long time.

[0005] Furthermore, if there are or gaps between the filter element and the frame, or between the filter unit and the facepiece, viruses and other pathogens can enter through these gaps. Therefore, it is essential that these gaps are securely sealed to prevent infection.

[0006] Another challenge is that high-performance filter materials with superior filtration capabilities are more expensive than simple mask filters, and it is desirable that they be reusable rather than being disposable after a single use. However, when filter materials are to be used multiple times, it is necessary to prevent the growth of attached bacteria and viruses and keep the filter material clean. While simple mask filters can be kept clean by washing, washing high-performance filter materials may lead to problems such as a significant decrease in filtration performance and reduced breathability. As a result, reusable masks equipped with high-performance filter materials have not yet been launched on the market.

[0007] The problem to be solved by the present invention is to solve at least one of the above problems. For example, it is to provide a medical filter unit with a novel structure that can be used in medical masks and the like, and has excellent collection performance against viruses and the like.

[0008] Furthermore, the present invention also aims to provide a method for manufacturing the medical filter unit described above.

[0009] Furthermore, the present invention, in some embodiments described later, also aims to provide a filter unit for a reusable mask and a reusable mask using the same, which allows a high-performance filter member to be used multiple times. [Means for solving the problem]

[0010] The following describes preferred embodiments for understanding the present invention. However, each embodiment described below is illustrative and can be combined with others as appropriate. Furthermore, the multiple components described in each embodiment can be recognized and adopted as independently as possible, and can be combined with any component described in another embodiment as appropriate. Thus, the present invention is not limited to the embodiments described below, and various other embodiments can be realized.

[0011] The first embodiment is a medical filter unit in which a filter member having a filter sheet is housed in a cylindrical frame provided on a resin support attached to a main body member, the filter sheet is folded back to form a pleated shape with a plurality of ridges and valleys, the first end edges of the filter sheet on both sides in the direction of continuity of the ridges and valleys and the second end edges of the filter sheet extending in a zigzag pattern on both sides in the width direction of the ridges and valleys are each fixed to the frame in an embedded state along their entire length, and the perimeter of the filter sheet is fixed to the frame in an embedded state around its entire circumference.

[0012] According to the medical filter unit structured in this embodiment, the filter sheet constituting the filter member is pleated with multiple peaks and valleys, thereby securing a large effective area of ​​the filter sheet and improving breathability. Therefore, even when using a fine-mesh filter sheet capable of capturing minute particles such as viruses, when applied to a medical mask, for example, the user may feel less breathless and be able to wear it for extended periods. Consequently, the effects of infection prevention and other benefits from wearing a medical mask can be sustained over a long period of time.

[0013] Furthermore, since the filter sheet is fixed all around to the frame that houses the filter member, it prevents gaps from forming between the filter member and the frame, thereby preventing viruses and other particles from entering through such gaps. Because the folded and pleated filter sheet is fixed all around to the frame, even when the height of the folded portion of the filter sheet is large, no gaps are formed between the filter member and the frame, resulting in high collection efficiency. Therefore, there is a great degree of freedom in setting the height of the folded portion, and it is possible to improve ventilation by increasing the height of the folded portion, for example.

[0014] Furthermore, since the filter sheet is fixed with its perimeter embedded in the frame, the folded filter sheet, which has multiple peaks and valleys, can be firmly and reliably fixed to the frame. Therefore, for example, if external pressure is applied to the filter sheet or frame and deformation occurs, it is possible to prevent the formation of a gap between the filter sheet and the frame due to delamination. In addition, it is possible to prevent the formation of unintended gaps due to, for example, poor fixing of the filter sheet to the frame during the molding of the frame (for example, poor fixing of both ends in the width direction of the peaks and valleys of the filter sheet to the frame).

[0015] A second embodiment is a medical filter unit as described in the first embodiment, wherein the second edge of the filter sheet is provided with a fixing end that is inclined in the circumferential direction of the frame and fixed to the frame in an embedded state.

[0016] In a medical filter unit with a structure according to this embodiment, the fixing end, which is embedded and fixed to the frame, is inclined in the circumferential direction of the frame, thereby increasing the fixing area of ​​the second end edge with the fixing end to the frame. Therefore, the filter sheet is stably fixed to the frame at the second end edge.

[0017] A third embodiment is a medical filter unit as described in the first or second embodiment, wherein the first edge of the filter sheet is provided with a fixing piece that is folded back and fixed to the frame in an embedded state.

[0018] According to the medical filter unit structured in this embodiment, the first edge of the filter sheet is provided with a folded-over fixing piece. By fixing the fixing piece to the frame in an embedded state, the first edge of the filter sheet can be more stably fixed to the frame. Furthermore, since the non-embedded portion of the fixing piece appears to be compressed compared to the embedded portion, it is possible to increase the effective area of ​​the filter sheet and improve the fixing strength.

[0019] A fourth embodiment is a medical filter unit in which a filter member having a filter sheet is housed in a cylindrical frame provided on a resin support attached to a main body member, the filter sheet is folded back to form a pleated shape with a plurality of ridges and valleys, and a bead portion is provided that extends in the direction of continuity of the ridges and valleys of the filter sheet and holds the ridges and valleys, and the frame portion has a fixing projection that protrudes toward the bead portion and is fixed to the bead portion.

[0020] According to the medical filter unit structured in this embodiment, the shape stability of the folded filter sheet is enhanced by the bead portion, making it easier to handle the filter member, for example, during the process of fixing the filter member to the frame portion. Furthermore, by fixing the fixing protrusion of the frame portion to the bead portion, which has particularly excellent shape stability in the filter member, the fixing strength between the filter member and the frame portion is improved, and deformation of the filter member relative to the frame due to external pressure can be suppressed. In addition, for example, if the bead portion is formed from a thermoplastic resin and the bead portion melts due to the heat generated during the molding of the frame portion, the fixing protrusion and the molten bead portion will be integrally fixed, further improving the fixing strength.

[0021] A fifth aspect is a method for manufacturing a medical filter unit in which a filter member having a filter sheet is housed in a cylindrical frame provided on a resin support attached to a main body member, comprising: a first step of setting the filter member, which has bead portions for holding the peaks and valleys of a filter sheet that is folded back in a pleated manner with a plurality of peaks and valleys connected together, into a molding die for the support; and a second step of filling the cavity of the molding die with a resin material to form the support, with the first end edges of the filter sheet located on both sides in the continuous direction of the peaks and valleys and the second end edges of the filter sheet located on both sides in the width direction of the peaks and valleys and extending in a zigzag pattern continuously within the cavity of the molding die, thereby forming a frame portion of the support in which the filter sheet is fixed around its entire circumference.

[0022] According to the medical filter unit obtained by the manufacturing method according to this embodiment, the filter sheet constituting the filter member is pleated with multiple peaks and valleys, thereby securing a large effective area of ​​the filter sheet and improving breathability. Therefore, even when using a fine-mesh filter sheet capable of capturing minute particles such as viruses, when applied to a medical mask, for example, the user may not feel suffocated and may be able to wear it for a long time. Consequently, the effects of infection prevention and other benefits from wearing a medical mask can be enjoyed continuously for a long period of time. Furthermore, since the perimeter of the filter sheet is fixed to the frame that houses the filter member all around, it prevents the formation of gaps between the filter member and the frame, thereby preventing the entry of viruses and other particles through such gaps. Because the perimeter of the folded and pleated filter sheet is fixed to the frame all around, even when the height dimension of the folded dimension of the filter sheet is large, no gap is formed between the filter member and the frame, and high collection efficiency can be achieved. Therefore, there is a great degree of freedom in setting the height of the folded dimension, and it is possible to improve breathability by increasing the height of the folded dimension, for example.

[0023] The sixth aspect is a medical filter unit, in which a filter member having a filter sheet is housed in a cylindrical frame portion provided on a resin support attached to a main body member, the filter sheet is folded into a pleated shape with a plurality of valleys connected, the support has a plate-shaped portion that extends from an axial end portion of the frame portion to the outer periphery, an injection port mark of a resin material is located on the plate-shaped portion, and a groove-shaped portion that is located on the inner peripheral side of the injection port mark and extends in the circumferential direction of the frame portion is formed and opened on an end surface of the support on which the plate-shaped portion is formed.

[0024] According to the medical filter unit having the structure according to this aspect, when the support is molded, the resin material injected from the injection port into the molding cavity of the support is restricted by receiving resistance from the mold protrusion that forms the groove-shaped portion for the flow to the inner peripheral side. Thereby, it is possible to prevent the filling pressure of the resin material filled in the molding cavity and the flow in the substantially vertical direction from directly acting on the filter member. For example, deformation of the filter member due to the filling pressure of the resin material and unintended intrusion of the resin material into the valleys of the filter member are prevented.

[0025] The seventh aspect is the medical filter unit according to the sixth aspect, in which the groove-shaped portion extends along the second edge portion on the outer peripheral side of the second edge portion of the filter sheet.

[0026] According to the medical filter unit having the structure according to this aspect, it is possible to prevent the filling pressure of the resin material from directly acting on the second edge portion that is likely to have a problem with the entry of the resin material due to its zigzag extension.

[0027] The eighth aspect is a medical filter unit, in which a filter member having a filter sheet is housed in a cylindrical frame portion provided on a resin support attached to a main body member, the filter sheet is folded into a pleated shape with a plurality of valleys connected, the support is made of an elastic body, and the support has a seal portion that surrounds the outer periphery of the frame portion over the entire circumference and is compressed by the main body member, and is formed integrally with the frame portion.

[0028] According to the medical filter unit constructed in accordance with this embodiment, when the filter unit is attached to the main body member, the sealing structure, formed by pressing the sealing portion against the main body member, prevents the formation of a gap between the filter unit and the main body member. Furthermore, since the frame portion and the sealing portion are integrally formed, the formation of a gap between the frame portion and the sealing portion can be prevented. Therefore, inhaled air can be reliably passed through the filter sheet, preventing viruses and other pathogens from entering by short-circuiting between the filter unit and the main body member or between the frame portion and the sealing portion.

[0029] The ninth aspect is a medical filter unit as described in the eighth aspect, wherein the sealing portion is sandwiched between the main body member, thereby forming a first sealing structure that seals the space between the support and the main body member in the direction in which the sealing portion is sandwiched by the main body member, and a second sealing structure that seals the space between the support and the main body member in a direction intersecting the direction in which the sealing portion is sandwiched by the main body member.

[0030] According to the medical filter unit structured in this embodiment, when the filter unit is attached to the main body member, the sealing portion is sandwiched by the main body member, thereby sealing the space between the filter unit's support and the main body member. As a result, the inhaled air reliably passes through the filter member without short-circuiting between the support and the main body member, allowing for highly efficient capture of viruses and other particles.

[0031] Because the sealing portion is sandwiched between the main body members, a double sealing structure consisting of a first sealing structure and a second sealing structure is provided between the support and the main body members, thereby improving the reliability of the seal. Moreover, since the first sealing structure and the second sealing structure are formed by sandwiching the sealing portion in one direction with the main body members, there is no need to provide separate sealing members, thus simplifying the structure and facilitating manufacturing.

[0032] The tenth embodiment is a medical filter unit in which a filter member having a filter sheet is housed in a cylindrical frame provided on a resin support attached to a main body member, the filter sheet is folded back to form a pleated shape with a plurality of ridges and valleys, the first end edges of the filter sheet on both sides in the direction of continuity of the ridges and valleys and the second end edges of the filter sheet extending in a zigzag pattern on both sides in the width direction of the ridges and valleys are each fixed to the frame along its entire length, the entire circumference of the filter sheet is fixed to the frame, and both ends of the frame in the axial direction protrude outward in the axial direction from the filter member.

[0033] In a medical filter unit with a structure according to this embodiment, the size of the frame is made larger than that of the filter member in the cylindrical length direction, providing ample space for the frame to which the filter member is fixed, thereby stabilizing the fixing of the filter member to the frame. Furthermore, since both axial ends of the frame protrude from the filter member, it is difficult for the user to touch the filter member when gripping the frame, thus protecting the filter member. This prevents crushing of the filter member caused by contact with the user or other components, and also prevents defects such as changes in the effective area due to deformation of the filter sheet.

[0034] The eleventh embodiment is a medical filter unit in which a filter member having a filter sheet is housed in a cylindrical frame provided on a resin support attached to a main body member, the filter sheet is folded back to form a pleated shape with a series of peaks and valleys, the frame is an elastic body, and rib-like portions protruding from the outer circumferential surface of the frame and extending in the axial direction of the frame are integrally formed with the frame.

[0035] In a medical filter unit with a structure according to this embodiment, the shape stability and dimensional accuracy of the frame that houses the filter member are improved by the reinforcing effect of the rib-like portion. Furthermore, by providing the rib-like portion, the thickness dimension of the main body of the frame can be kept small while the rib-like portion improves the axial rigidity and shape stability of the frame. In addition, the rib-like portion can be used to ensure strength during demolding after molding of the filter member and to ensure a contact surface for the demolding pin. Moreover, because the frame is less prone to deformation, even when the height dimension of the folded dimension of the filter sheet is large and the axial length of the filter member is long, deformation such as relative displacement between the axial folded ends of the filter sheet in the filter member is less likely to occur.

[0036] A twelfth embodiment is a medical filter unit in which a filter member having a pleated filter sheet that is folded back to form a series of peaks and valleys is housed in a polygonal cylindrical frame provided on a resin support attached to a main body member, the support is provided with a plate-like portion that extends outward from the frame, and the plate-like portion has resin material injection port marks located on the outer circumference of each side of the frame.

[0037] According to the medical filter unit structured in this embodiment, the resin material that forms the frame is injected from the outer circumference of each side of the polygonal cylindrical frame. This reduces the injection pressure (molding pressure) of the resin material injected from multiple locations during the molding of the frame, and the force acting on the filter member is distributed and applied to the parts of the filter member that are fixed to each side of the frame. Therefore, deformation of the filter member due to the molding pressure of the frame is suppressed, and a reduction in the effective area due to deformation of the filter member is prevented.

[0038] The 13th embodiment is a filter unit for a reusable mask, in which a filter member is arranged inside a fluid-impermeable cylindrical frame, the filter sheet constituting the filter member is folded back to form a pleated shape with multiple peaks and valleys, the height of the frame is greater than the height of the filter member, the height dimension of the frame is 20 mm or more, and the inner dimension of the frame is 2.5 times or less the height dimension.

[0039] According to the filter unit for reusable masks constructed in accordance with this embodiment, the frame housing the filter member is a relatively elongated cylindrical shape. This suppresses the flow of gas between the inside and outside of the frame, and for example, when spraying disinfectant onto the filter member to reduce bacteria and viruses attached to it, the disinfectant sprayed inside the frame is less likely to escape to the outside. Therefore, the disinfectant spray particles (including vapors) remaining inside the frame spread over a wide area within the frame housing the filter member and diffuse easily within the internal space of the frame, adhering to the entire filter member, disinfecting the entire filter member, and efficiently preventing the growth of bacteria and viruses. Furthermore, with disinfectant spraying, clogging of the high-performance filter member and a decrease in collection performance are not problems. As a result, it is possible to maintain the excellent collection performance and breathability of the filter member while also obtaining the economic benefits of reusing the filter member.

[0040] Furthermore, because the fine particles (including vapors) of the sprayed disinfectant float within the frame and adhere to a wide area of ​​the filter material's surface, the disinfectant adheres to areas that are difficult to spray directly, such as the valleys of the pleats, allowing for effective disinfection over a wide area. In particular, the gaps between the peaks and valleys of the pleats tend to widen outwards, making it easier for the disinfectant sprayed from the outside to reach deeper into these gaps.

[0041] The 14th embodiment is a filter unit for a reusable mask as described in the 13th embodiment, wherein a bead portion is provided that extends in the continuous direction of the peaks and valleys of the filter sheet and holds the peaks and valleys.

[0042] According to the filter unit for reusable masks with a structure conforming to this embodiment, the pleated shape formed by the peaks and valleys of the filter member is more easily maintained, and overlapping of the filter sheet in contact with the surface is prevented, for example, making it easier for disinfectant to flow into the gaps between the peaks and valleys of the filter sheet and to adhere to the bottom of the valleys.

[0043] The 15th aspect is a filter unit for a reusable mask as described in the 13th or 14th aspect, wherein the surface of the filter sheet is made of nonwoven fabric.

[0044] According to the filter unit for reusable masks constructed in accordance with this embodiment, the disinfectant spray particles adhere to the fine fibers on the surface of the nonwoven fabric, making it easier for the disinfectant spray particles to be captured across the entire filter sheet. Therefore, the disinfectant spray particles floating within the frame adhere to a wide area of ​​the filter sheet, allowing for widespread disinfection.

[0045] The sixteenth embodiment is a filter unit for a reusable mask described in any one of the thirteenth to fifteenth embodiments, wherein both axial ends of the frame portion protrude outward in the axial direction from the filter member.

[0046] According to the filter unit for reusable masks with a structure conforming to this embodiment, the spray particles of disinfectant sprayed into the frame are more likely to remain within the frame, and the filter sheet can be disinfected more effectively by spraying the disinfectant.

[0047] The 17th aspect is a reusable mask comprising a filter unit for a reusable mask as described in any one of the 13th to 16th aspects.

[0048] According to the reusable mask constructed in accordance with this embodiment, the filter unit, which has excellent particle collection performance for target particles such as bacteria and viruses and also has good breathability, can be used repeatedly multiple times. [Effects of the Invention]

[0049] According to the present invention, for example, it is possible to provide a medical filter unit that can be used in medical masks and has excellent collection performance against viruses and the like. Furthermore, in some embodiments of the invention described above, it is possible to provide a filter unit for reusable masks or a reusable mask using said filter unit, which allows the high-performance filter member to be used multiple times. [Brief explanation of the drawing]

[0050] [Figure 1] Front view showing a medical filter unit as a first embodiment of the present invention. [Figure 2] Rear view of the medical filter unit shown in Figure 1. [Figure 3] Right side view of the medical filter unit shown in Figure 1. [Figure 4] Sectional view of IV-IV in Figure 1 [Figure 5] VV section diagram in Figure 1 [Figure 6] Front view of the support structure constituting the medical filter unit shown in Figure 1. [Figure 7] Plan view of the support shown in Figure 6. [Figure 8] Right side view of the support shown in Figure 6. [Figure 9] Rear view of the support shown in Figure 6. [Figure 10] A close-up photograph showing a portion of the medical filter unit shown in Figure 1. [Figure 11A] Figure 1 illustrates the attachment of the medical filter unit to the filter support member, showing the area before the seal portion is sandwiched by the filter support member. [Figure 11B] Figure 1 illustrates the attachment of the medical filter unit to the filter support member, showing the part after the seal has been sandwiched by the filter support member. [Figure 12] Figure 1 is a perspective view showing a mask equipped with a medical filter unit in a worn state. [Figure 13]Figure 12 is a perspective view showing the mask body, which makes up the mask, from a different angle. [Figure 14] Figure 12 is a cross-sectional view of the mask, corresponding to the XIV-XIV section in Figure 13. [Figure 15] Figure 14: Cross-sectional view between XV and XV [Modes for carrying out the invention]

[0051] Embodiments of the present invention will be described below with reference to the drawings.

[0052] Figures 1 to 5 show a medical filter unit (hereinafter referred to as "filter unit") 10 as a first embodiment of the present invention. The filter unit 10 comprises a filter member 12 and a resin support 14. In the following description, as a general rule, the vertical direction refers to the vertical direction in Figure 1, the left-right direction refers to the left-right direction in Figure 1, and the front-back direction refers to the left-right direction in Figure 3. Note that the directions defined here are for convenience to facilitate understanding and do not necessarily coincide with, for example, the vertical up-down direction or the horizontal direction when wearing a medical mask.

[0053] The filter member 12 includes a pleated filter sheet 16. The filter sheet 16 is a porous filtration membrane formed from a nonwoven fabric or the like.

[0054] The filter sheet 16 is pleated by a folding machine and folded multiple times to form a pleated shape with multiple peaks and valleys. The folded filter sheet 16 has peaks and valleys (folded portions) 20 that form corners or curve with a small radius, and both sides of the peaks 20 are inclined portions 21 that extend linearly with approximately the same angle of inclination. The distance between adjacent front peaks 20, 20 and rear peaks 20, 20 in the direction of continuity of the peaks and valleys (vertical direction) of the filter sheet 16 is kept approximately constant, thereby improving breathability by efficiently securing the effective area.

[0055] In the direction of continuity of the multiple peaks and valleys (vertical direction), both ends of the filter sheet 16 are defined as first end edges 22, 22 that extend linearly in the left-right direction. In the width direction of the peaks and valleys (left-right direction), both ends of the filter sheet 16 are defined as second end edges 24, 24 that fold back in a zigzag pattern and extend continuously.

[0056] The pleated filter sheet 16 is formed so that its width is longer than the inner width dimension of the frame portion 30, which will be described later. The filter sheet 16 has 10 or more pleats formed by the pleating process, which are folded back so as to be convex toward the front, and in this embodiment, 16 pleats are formed.

[0057] The first edges 22,22 of the filter sheet 16 have fixing pieces 26,26. As shown in Figure 4, the fixing pieces 26 are formed by folding back the end of the filter sheet 16 and protrude outward in the vertical direction. It is desirable that the fixing pieces 26 are inclined at an angle α less than 45 degrees with respect to the vertical direction, so that when the frame portion 30 is formed with resin, the resin can easily wrap around both sides of the fixing pieces 26 and securely fix the fixing pieces 26 to the frame portion 30. The angle α of the fixing pieces 26 with respect to the vertical direction may be, for example, less than 30 degrees, less than 15 degrees, or about 10 degrees or about 5 degrees.

[0058] The pleated filter sheet 16 has its pleat shape stabilized by a bead portion 28. The bead portion 28 is formed by, for example, a thermoplastic adhesive. That is, the bead portion 28 is formed when adhesive, which is applied linearly to both the front and back surfaces of the filter sheet 16 so as to extend in the direction of continuity of the peaks and valleys of the pleats (vertical direction), solidifies after pleating, and is provided extending linearly in the direction of continuity of the peaks and valleys. The folded shape of the filter sheet 16 is maintained by the bead portion 28 as the inclined portions 21, 21 of adjacent peaks and valleys are positioned relative to each other by the bead portion 28. The bead portion 28 maintains the pleat shape by limiting the separation of the inclined portions 21, 21 by the adhesive applied to the inclined portions 21, 21 of adjacent peaks and valleys adhering to each other, and by the adhesive solidified between the inclined portions 21, 21 acting as a spacer to limit the proximity of the inclined portions 21, 21.

[0059] In this embodiment, two bead portions 28, 28 are provided at positions separated from each other in the width direction (left-right direction) of the folded filter sheet 16. The two bead portions 28, 28 are located midway between the center and both ends of the filter sheet 16 in the left-right direction, and the second edge portions 24, 24 on both sides of the filter sheet 16 protrude outward in the left-right direction compared to the bead portions 28, 28. The filter member 12 of this embodiment is formed by providing the bead portions 28, 28 on the pleated filter sheet 16. The distance between the second edge portion 24 of the filter sheet 16 and the bead portion 28 on the side closer to the second edge portion 24 is shorter than the distance between the two bead portions 28, 28. As a result, the shape of the filter sheet 16 on the side of the second edge portion 24 is stable, and defects such as adhesion and peeling are less likely to occur between the second edge portion 24 of the filter sheet 16 and the frame portion 30.

[0060] As shown in Figures 6 to 8, the support 14 includes a cylindrical frame portion 30. The frame portion 30 in this embodiment is a rectangular tube with a substantially rectangular cross-section that extends in the front-to-back direction. An internal hole that penetrates the frame portion 30 in the front-to-back direction, which is the axial direction, is a housing hole 32 for housing the filter member 12. The frame portion 30 in this embodiment is an elastic body made of soft synthetic resin. A resin elastomer is preferred as the forming material for the frame portion 30, and elastomers such as polyurethane or soft polyvinyl chloride can be used. The frame portion 30, being an elastic body made of synthetic resin, has fluid impermeability that does not allow the permeation of liquids and gases.

[0061] Rib-like portions 34 are provided on the outer circumferential surface of the frame portion 30. As shown in Figure 6, the rib-like portions 34 protrude outward from the frame portion 30, extend axially with a substantially semicircular cross-section, and their rear ends are connected to a plate-like portion 40, which will be described later (see Figure 4). In this embodiment, three rib-like portions 34 are provided on each of the four walls of the frame portion 30, which has a rectangular cross-section, spaced apart from each other in the circumferential direction of the frame portion 30. The rib-like portions 34 in this embodiment are integrally formed with the frame portion 30. The size, position, and number of the rib-like portions 34 are not limited, and it is also possible to use a frame portion 30 without providing rib-like portions 34, for example, one with an outer circumferential surface that is substantially similar in shape to the inner circumferential surface.

[0062] Fixing protrusions 36 are provided on the inner circumferential surface of the frame portion 30. The fixing protrusions 36 project from the upper and lower walls of the frame portion 30 toward the housing hole 32, and are provided at positions corresponding to the upper and lower ends of the bead portion 28 when the filter member 12 is housed, as described later. Therefore, two fixing protrusions 36, 36 are arranged on the upper and lower walls of the frame portion 30, at positions separated from each other in the left-right direction. The width dimension of the fixing protrusions 36 in the left-right direction is larger than that of the bead portion 28, so that even if the position of the bead portion 28 is varied in the left-right direction, the ends of the bead portion 28 will be located on the fixing protrusions 36. The fixing protrusions 36 are formed by the resin material seeping into the filter member 12, and their specific shape may differ depending on the degree of seepage into the filter member 12. Therefore, the specific shape of the frame portion 30, which is formed by defining its shape with a mold, can be specified as a shape that does not include the fixing projection 36, as shown in Figure 6.

[0063] The upper and lower walls of the frame portion 30 are stepped surfaces 38, where the rear surface of the inner circumference is positioned in front of the rear surface of the outer circumference. The stepped surfaces 38 extend linearly in the left-right direction with a roughly constant vertical width dimension that is smaller than the thickness dimension of the upper and lower walls of the frame portion 30. As a result, it is difficult for external force to be applied to the filter sheet 16 from the rear end side of the frame portion 30.

[0064] A plate-like portion 40 is provided at the rear end of the frame portion 30. The plate-like portion 40 protrudes outward from the rear end of the frame portion 30 and is a thin plate-like shape with a substantially circular outer shape. The frame portion 30 and the plate-like portion 40 have different shapes from each other; the frame portion 30 has a rectangular inner and outer shape to facilitate fixing the entire circumference of the filter sheet 16, while the plate-like portion 40 has a circular outer shape so that the filter support member 48, which serves as the main body member, does not become too large. The front surface of the plate-like portion 40 is an inclined surface that slopes backward as it moves toward the outer circumference, and it gradually becomes thinner as it moves away from the frame portion 30 toward the outer circumference. The plate-like portion 40 is integrally formed with the frame portion 30 and is made of an elastic material, similar to the frame portion 30.

[0065] An annular sealing portion 42 is provided on the outer circumference of the plate-shaped portion 40. The sealing portion 42 is located further outward than the plate-shaped portion 40 and is arranged to surround the entire outer circumference of the frame portion 30. The sealing portion 42 is integrally formed with the plate-shaped portion 40 and is made of an elastic material. The sealing portion 42 is equipped with an annular sealing lip 43 that protrudes forward. The sealing lip 43 has a surface with a substantially arc-shaped cross-section, and its radial width gradually decreases towards the protruding tip. The protruding height of the sealing lip 43 is sufficiently small compared to the axial height dimension of the frame portion 30, and in this embodiment, it is smaller than the thickness dimension of the plate-shaped portion 40. The sealing lip 43 has a flattened cross-sectional shape in which the protruding height dimension is smaller than the radial width dimension.

[0066] As shown in Figure 9, groove-shaped portions 44, 44 are formed on the rear surface of the plate-shaped portion 40. The groove-shaped portions 44 extend linearly in the vertical direction along the left and right side walls of the frame portion 30 and open to the rear surface. The upper and lower ends of the groove-shaped portions 44 are located inward in the vertical direction from the upper and lower side walls of the frame portion 30. In this embodiment, the groove-shaped portion 44 has an expanding shape in which the groove cross-section gradually widens towards the rear. In this embodiment, the groove-shaped portion 44 is provided at the boundary between the left and right side walls of the frame portion 30 and the plate-shaped portion 40, and a part of the groove-shaped portion 44 is located at the rear end of the frame portion 30. Preferably, the depth dimension of the groove-shaped portion 44 is greater than half the thickness dimension of the inner circumference of the plate-shaped portion 40.

[0067] An injection port mark 45 is located on the rear surface of the plate-shaped portion 40. The injection port mark 45 is the mark of an injection port (not shown) used to inject resin material into the cavity of the molding die during the molding of the support 14, which will be described later. It is formed, for example, by removing the runner, and exhibits irregularities and differences in surface texture on the rear surface of the plate-shaped portion 40. In this embodiment, four injection port marks 45 are provided at approximately equal intervals in the circumferential direction of the plate-shaped portion 40. Two are located vertically separated from the upper and lower walls of the frame portion 30, and the other two are located horizontally separated from the left and right walls of the frame portion 30. In short, the injection port marks 45 are formed on the outer circumference of each side (wall) of the rectangular cylindrical frame portion 30. The left and right injection port marks 45, 45 are located inward in the left-right direction relative to the groove-shaped portions 44, 44, and the groove-shaped portions 44, 44 are located closer to the housing hole 32 than the left and right injection port marks 45, 45, and extend in the vertical direction, which is the circumferential direction of the frame portion 30. The injection port marks 45 can be made virtually invisible to the naked eye depending on the molding conditions such as the mold structure and resin material, as well as post-molding treatment.

[0068] As shown in Figures 1, 2, 4, and 5, the frame portion 30 of the support 14 houses the filter member 12. A filter unit 10 having a structure according to the present invention, in which the filter member 12 is housed in the frame portion 30, can be obtained based on a manufacturing method including the first and second steps described below.

[0069] Specifically, a filter member 12 is prepared in advance, which has a structure in which two bead portions 28, 28 are formed that extend in the direction of continuity of the peaks and valleys of the filter sheet 16 and hold the peaks and valleys of the filter sheet 16, for a pleated filter sheet 16 which is made by folding a flat filtration membrane in a zigzag pattern to create multiple peaks and valleys. The first step is completed by setting the pre-prepared filter member 12 into a molding die of a support 14 (not shown).

[0070] In the second step, the filter member 12, which is set in the mold for forming the support 14, is inserted into the frame portion 30 of the support 14 during the molding of the support 14. That is, in the first step, the filter member 12 set in the mold for forming the support 14 has its first edge portions 22,22 and second edge portions 24,24 protruding into the molding cavity of the frame portion 30. With the filter member 12 set in the mold for forming the support 14, the resin material is filled into the cavity of the mold for forming the support 14, and the support 14 is molded with the resin. This completes the second step of molding the support 14 with the filter member 12 inserted.

[0071] The mold for forming the support 14 includes an outer periphery mold for forming the outer circumferential surface of the frame portion 30 and a pair of comb-shaped molds for forming the inner circumferential surface of the frame portion 30, with the molding cavity of the frame portion 30 formed between the outer periphery mold and the comb-shaped molds. The filter member 12 has a length in the width direction (left-right direction) that is longer than the width direction length of the inner circumferential portion of the frame portion 30, and a length in the direction of continuous peaks and valleys (up-down direction) that is longer than the vertical direction length of the inner circumferential portion of the frame portion 30, so that both the first end edges 22,22 and the second end edges 24,24 can protrude into the cavity of the frame portion 30. Furthermore, it is desirable that the amount of protrusion of the filter member 12 into the cavity be approximately the same on both sides in the width direction and on both sides in the direction of continuous peaks and valleys. The amount of the filter member 12 protruding into the cavity (the length embedded in the frame 30) is preferably 1 mm or more (2 mm or more in total, considering that both ends are embedded), and is less than the thickness of the wall portion of the frame 30. This makes it easier for the operator to position the filter member 12 in a position where both the left and right sides of the filter member 12 can be embedded in the cavity when setting the filter member 12 in the mold.

[0072] During the molding of the support 14 in the second step, the filter member 12 has its first edge portions 22,22 and second edge portions 24,24 of the filter sheet 16 positioned within the molding cavity of the frame portion 30 around its entire circumference. As a result, the filter member 12 is fixed to the frame portion 30 with the filter sheet 16 embedded around its entire circumference. Specifically, the fixing pieces 26,26 constituting the first edge portions 22,22 of the filter sheet 16 are embedded and fixed to the rear end portion of the frame portion 30, as shown in Figure 4, and the fixing ends 46,46 constituting the second edge portions 24,24 are embedded and fixed to the left and right walls of the frame portion 30, as shown in Figure 10. The frame portion 30 gradually becomes thicker from the front end to the rear end, and a plate-like portion 40 protrudes from the rear end portion of the frame portion 30, with the fixing pieces 26 located at the thickened rear end portion of the frame portion 30. Furthermore, the folding angle (90°-α) of the fixing piece 26 is greater than the folding angle of the inclined portion 21 at the peaks 20 of the pleats (1 / 2 of the narrow angle of the peaks 20). Therefore, without making the frame portion 30 particularly thick, it is possible to reduce the likelihood of poor embedding of the fixing piece 26 into the frame portion 30, and the weight load on the user wearing the mask can be reduced. In addition, the fixing piece 26 is located within 1 / 5 of the length dimension of the filter sheet 16 in the front-to-back direction, which is the height direction of the pleats. The length dimension of the part of the fixing piece 26 that is embedded in the frame portion 30 (tip portion) is greater than the length dimension between adjacent peaks 20, 20, and smaller than the thickness dimension of the upper and lower walls of the frame portion 30. This makes it possible to obtain a large fixing strength of the fixing piece 26 to the frame portion 30 while preventing the fixing piece 26 from protruding outward from the frame portion 30. The fixing end 46 is inclined in the circumferential direction of the frame portion 30, thereby increasing the fixing area to the frame portion 30. The inclination of the fixing end 46 may be formed by pre-processing the filter sheet 16, or it may be formed, for example, by the filling pressure of the resin material when molding the frame portion 30. It is preferable that the widthwise length of the filter sheet 16 before molding the frame portion 30 is greater than or equal to the length obtained by adding the vertical length of the peaks 20 of the filter sheet 16 (the diameter of the peaks 20 which have a semicircular cross-section) to the widthwise length of the inner circumference of the frame portion 30.

[0073] In this way, when the frame portion 30 is formed, the filter member 12 is fixed with its first edge portions 22,22 and second edge portions 24,24 embedded in the frame portion 30 along its entire length, so that the filter sheet 16 is fixed to the frame portion 30 around its entire circumference and attached to the support 14. As a result, the filter member 12 and the frame portion 30 are fixed together with a seal between them formed by the formation of the frame portion 30.

[0074] Comb-shaped molds are inserted into the peaks and valleys of the pleats of the filter member 12. This prevents resin material from entering the peaks and valleys of the pleats, even when the left and right ends (fixed ends 46) of the filter member 12 are embedded and fixed to the frame 30, thereby preventing a reduction in the effective area of ​​the filter member 12 due to it being covered by the forming material of the support 14.

[0075] The comb-shaped molds inserted into the peaks and valleys of the pleats of the filter member 12 are pressed against the surface or back surface of the filter sheet 16, and during the molding of the support 14, the filter sheet 16 is compressed in the thickness direction between the comb-shaped molds. In this way, by pressing the comb-shaped molds against the filter sheet 16 with a degree of compression, it is possible to more effectively prevent the forming material of the support 14 from entering the peaks and valleys of the pleats of the filter member 12. It is desirable that the amount of compression of the inner circumference of the pleated filter sheet 16 by the comb-shaped molds is such that the thickness returns to approximately the same as before compression when the compression is released. This prevents the fine pores of the porous filter sheet 16 from being blocked by excessive compression, and ensures the breathability of the filter member 12.

[0076] The comb-shaped mold presses more firmly against the base portion (inner end portion in the vertical direction) of the fixing piece 26 than the inner circumference portion of the pleated filter sheet 16, and the base portion of the fixing piece 26 exposed to the inner circumference from the frame portion 30 is compressed more significantly in the thickness direction. As a result, impregnation of the resin material is suppressed at the base portion of the fixing piece 26, preventing a reduction in the effective area of ​​the filter member 12. On the other hand, the tip portion of the uncompressed fixing piece 26 is embedded in the resin as if soaked in the resin material, preventing a gap from forming between the filter sheet 16 and the frame portion 30 that could allow viruses to enter. Furthermore, in the filter unit 10 after the support 14 has been molded, the base portion of the fixing piece 26 is thinner than the tip portion of the fixing piece 26 embedded in the frame portion 30 due to plastic deformation during compression. In addition, the base portion of the fixing piece 26 is thinner than the inclined portion 21 of the filter sheet 16 which is located closer to the center.

[0077] The portion of the fixing piece 26 that is embedded and fixed to the frame portion 30 (the tip portion) is not compressed during the molding of the support 14, and is in a state where it is easily impregnated with resin material. As a result, the fixing strength of the filter member 12 to the frame portion 30 is improved by the impregnation of resin material.

[0078] The tip surfaces of the comb-shaped mold are curved, creating a gap between the contacting fixing pieces 26 and the comb-shaped mold. The forming material of the support 14 enters this gap, allowing the fixing pieces 26 to be embedded and fixed to the rear end of the frame 30 with a larger fixing area. In other words, a curved surface is formed near the fixing pieces 26 on the inner circumferential surface of the frame 30, improving the fixing strength to the filter sheet 16.

[0079] The filter member 12 is provided with bead portions 28, which stabilizes the folded shape of the filter member 12 and makes it easier to handle the filter member 12 when setting it in the molding die of the support 14. In particular, the provision of two bead portions 28, 28 at positions separated from each other in the left-right direction further improves the shape stability of the filter member 12 and makes it easier to handle the filter member 12.

[0080] The fixing projection 36 of the frame portion 30 protrudes toward the bead portion 28 of the filter member 12 and is pressed against the bead portion 28. The heat generated during molding of the fixing projection 36 melts the end of the bead portion 28, and the bead portion 28 and the fixing projection 36 are fixed together as one, thereby ensuring a high degree of bonding strength between the filter member 12 and the frame portion 30. Furthermore, because the filter member 12 has high shape stability in the area where the bead portion 28 is provided, even when the fixing projection 36 is pressed against the bead portion 28 by the injection molding pressure during the molding of the frame portion 30, the shape change of the filter member 12 is suppressed and the pleated shape is maintained.

[0081] In this embodiment, an injection port for resin material is provided in the cavity of the plate-shaped portion 40, and the resin material injected from the injection port and flowing to the inner circumference comes into contact with and is fixed to the filter member 12. Since the filling pressure of the resin material during injection molding is greater closer to the injection port, a greater filling pressure acts on the filter member 12 at the portion fixed to the rear end of the frame portion 30 than at the portion fixed to the front end. Therefore, groove-shaped portions 44, 44 that open on the rear surface of the plate-shaped portion 40 are provided on the inner circumference side closer to the filter member 12 than the left and right injection port marks 45, 45, and extend vertically along the outer circumference of the second end edges 24, 24 of the filter sheet 16. In other words, the groove-shaped portions 44, 44 extend vertically between the left and right injection port marks 45, 45 and the second end edges 24, 24 of the filter member 12. As a result, the resin material flowing from the injection port toward the inner circumference is restricted by the mold forming the groove-shaped portions 44, 44, preventing large filling pressure from directly acting on the second end edges 24, 24 of the filter member 12. Consequently, deformation of the filter member 12 due to high-pressure filling of the resin material and the intrusion of resin material into the overlapping surfaces between the comb-shaped mold and the filter member 12 are prevented. Furthermore, because the groove-shaped portions 44 are formed near the boundary between the frame portion 30 and the plate-shaped portion 40, the area near the boundary is made thinner, which reduces or avoids the transmission of stress and deformation near the boundary between the frame portion 30 and the plate-shaped portion 40, which have different shapes, and is expected to improve the mutual shape stability.

[0082] Since the four injection ports are located on the outer circumference side of the molding cavities on each side of the frame 30, the injection pressure of the resin material can be set low, and the molding pressure of the resin acting on the filter member 12 set in the mold is distributed to each side of the filter member 12 (first edge portions 22, 22 and second edge portions 24, 24), preventing deformation of the filter member 12. It is preferable that the injection ports be located on the outer circumference side of each side of the frame 30, but for example, injection ports can be provided in two locations, and injection ports can be provided on the outer circumference of the side that is particularly weak against molding pressure.

[0083] The frame portion 30 is reinforced by multiple rib-like portions 34, which suppresses deformation of the frame portion 30 due to thermal shrinkage after molding, and maintains the shape of the filter member 12. This prevents the effective area of ​​the filter member 12 from decreasing due to deformation, and ensures the desired airflow. Furthermore, if the frame portion 30 is an elastic body, deformation of the frame portion 30 due to applied external force may adversely affect its adhesion to the filter sheet 16. However, the rib-like portions 34 make deformation of the frame portion 30 difficult, thus making it difficult for the frame portion 30 to adhere to and peel off the filter sheet 16. In this embodiment, since the frame portion 30 is rectangular tubular, the strength (deformation rigidity) of the frame portion 30 tends to be lower at the edges than at the corners. However, by providing rib-like portions 34 at the edges of the frame portion 30, the deformation rigidity of the frame portion 30 can be effectively increased with a lighter structure than when the entire frame portion 30 is thickened. The rib-shaped portions 34 may be formed to extend in the circumferential direction, but it is preferable to form them to extend in the axial direction, as this allows for the formation of more rib-shaped portions 34. The rib-shaped portions 34 can also be used to push the support 14 out of the mold by pressing a demolding pin against it when removing the support 14 from the mold.

[0084] According to the filter unit 10 of this embodiment, since the filter member 12 is composed of a folded pleated filter sheet 16, the effective area of ​​the filter sheet 16 is large, improving breathability. Therefore, by adopting a filter sheet 16 with a large basis weight, the collection efficiency can be improved while reducing breathlessness when worn, and the medical mask equipped with the filter unit 10 can be worn for a long time, preventing the entry of viruses and other pathogens for an extended period.

[0085] Preferably, the height dimension of the pleats in the filter sheet 16 is greater than half of the inner or outer dimension in the width or vertical direction of the frame portion 30, and smaller than the radial width dimension of the plate-shaped portion 40 including the sealing portion 42, or smaller than the radius of the plate-shaped portion 40 including the sealing portion 42. This allows for sufficient ventilation with a large effective area using a filter member 12 of an appropriate size for a mask.

[0086] As shown in Figure 4, in the front-to-back direction, which is the axial direction of the frame portion 30, the front end of the frame portion 30 protrudes forward of the front end of the filter member 12 housed in the frame portion 30. Furthermore, the stepped surface 38 of the frame portion 30 is positioned approximately at the same location as the rear end of the filter member 12 in the axial direction of the frame portion 30, and the portion of the rear surface of the frame portion 30 that is not adjacent to the stepped surface 38 protrudes backward of the rear end of the filter member 12. In this way, both axial ends of the frame portion 30 protrude axially outward from the filter member 12, thereby protecting the filter member 12 from the frame portion 30. For example, when attaching the filter unit 10 to the filter support member 48 described later, it is possible to prevent the filter member 12 from deforming by contacting the filter support member 48.

[0087] In this embodiment, the axial front end of the frame portion 30 is located in front of the front top portion 20 of the filter member 12, which is folded over around its entire circumference, and the axial rear end of the frame portion 30 is located behind the rear top portion 20 of the filter member 12 around its entire circumference. As a result, the entire perimeter of the filter member 12 is covered by the frame portion 30, and the filter member 12 is protected around its entire circumference by the axial end of the frame portion 30, effectively preventing contact between the filter member 12 and other components.

[0088] Incidentally, as shown in Figures 11A and 11B, the filter unit 10 is attached to the filter support member 48 in a sealed state by sandwiching the seal portion 42 of the support 14 between the first member 50 and the second member 52 that constitute the filter support member 48. That is, as shown in Figure 11A, the rear part of the filter unit 10, including the plate-shaped portion 40, is inserted into a housing recess 54 provided in the first member 50. With the filter unit 10 inserted into the housing recess 54, the clamping portion 56 of the second member 52, which is inserted into the housing recess 54 from the front, is pressed against the seal lip 43 of the seal portion 42, and as shown in Figure 11B, the seal portion 42 is sandwiched and compressed in the front-rear direction between the bottom wall of the housing recess 54 and the clamping portion 56. The clamping portion 56 may be pressed so that its central part is located at the top of the seal lip 43, or the clamping portion 56 may be pressed so that its central part is radially inward from the top of the annularly formed seal lip 43. This makes it easier to deform the seal lip 43, which is pressed by the clamping portion 56, radially outward, thereby facilitating the realization of the second seal structure 60 described later.

[0089] In this configuration, the seal portion 42 is pressed against the first member 50 in the clamping direction of the seal portion 42, which is the axial direction of the frame portion 30, and is in close contact with it. A first seal structure 58 is provided to seal the space between the first member 50 and the rear surface of the seal portion 42. Furthermore, the clamped and compressed seal portion 42 expands toward the outer circumference, which is in a direction intersecting the compression direction, and is pressed against the inner surface of the peripheral wall of the receiving recess 54 in the first member 50, and is in close contact with it. A second seal structure 60 is provided to seal the space between the first member 50 and the outer surface of the seal portion 42. In this way, the seal portion 42 is clamped between the first member 50 and the second member 52, forming a double seal structure 58, 60, which ensures a higher level of airtightness between the filter support member 48 and the filter unit 10. To achieve such a double seal, it is desirable that the seal portion 42 be made of a material with a Poisson's ratio close to 0.5.

[0090] In this embodiment, the entire support 14 is a single molded product made of an elastic material, with a frame portion 30, a plate-shaped portion 40, and a sealing portion 42 integrally formed, and the sealing portion 42 is arranged to surround the outer circumference of the frame portion 30 over its entire circumference. In this way, the sealing portion 42 that constitutes the sealing structures 58, 60 for the filter support member 48 is integral with the frame portion 30 that houses the filter member 12, and the sealing structures 58, 60 are provided around the entire circumference of the frame portion 30. As a result, for example, intake air does not pass between the frame portion 30 and the sealing portion 42, and the intake air is guided to pass reliably through the filter member 12.

[0091] The plate-shaped portion 40 is made thinner towards the outer circumference, and the sealing portion 42 provided on the outer circumference of the plate-shaped portion 40 is thinner than the inner circumference end of the plate-shaped portion 40. As a result, when the filter unit 10 is installed between the first and second members 50 and 52, the sealing portion 42 is easily compressed and deformed, resulting in more stable and effective sealing performance. Furthermore, even if the second member 52, which compresses the sealing portion 42 and fixes the filter unit 10 by screwing it into the first member 50, were to come into contact with the plate-shaped portion 40, the plate-shaped portion 40 would deform easily, preventing assembly problems of the second member 52, and ensuring stable sealing performance through compression of the sealing portion 42 (seal lip 43).

[0092] Figures 12 to 15 show an example of a half-face mask 80 equipped with a filter unit 10 according to the first embodiment. The mask 80 comprises a mask body 82 that covers the wearer's mouth and nose, and a band 84 that positions and holds the mask body 82 on the wearer A's face. The mask body 82 comprises a facepiece 86 that is attached to the wearer A's face, and a filter unit 10 held by the facepiece 86.

[0093] The facepiece 86 comprises a filter support member 48 that supports the filter unit 10, and a face contact body 88 positioned between the filter support member 48 and the face of the wearer A. As shown in Figures 14 and 15, the filter support member 48 has a divided structure comprising a first member 50 connected to the face contact body 88 and a second member 52 that covers the opening on the front side of the first member 50.

[0094] The first member 50 comprises a substantially cylindrical peripheral wall 90 and an annular plate contact portion 92 that protrudes inward from the peripheral wall 90. The plate contact portion 92 is not necessarily limited to an annular plate shape that is continuous around the entire circumference, but may be provided partially in the circumferential direction of the peripheral wall 90, for example. The filter unit 10 is inserted into the inner circumference side of the peripheral wall 90 of the first member 50, and the plate-shaped portion 40 of the filter unit 10 is superimposed on the front surface of the plate contact portion 92 of the first member 50. The radial relative movement of the filter unit 10 with respect to the first member 50 is limited by the contact between the plate-shaped portion 40 and the peripheral wall 90.

[0095] The second member 52 comprises a cylindrical wall portion 94 and a front wall portion 96 that covers the front opening of the cylindrical wall portion 94, and is generally a bottomed cylindrical shape. Multiple ventilation holes 98 are formed through the front wall portion 96. The shape of the openings of the ventilation holes 98 is not particularly limited, but in this embodiment, as shown in Figure 12, they are slit-shaped, extending radially while being inclined in the circumferential direction, and are formed at predetermined intervals in the circumferential direction.

[0096] The cylindrical wall portion 94 of the second member 52 is connected to the peripheral wall 90 of the first member 50 in a manner that allows for attachment and detachment. The connection structure between the first member 50 and the second member 52 is configured such that, for example, the cylindrical wall portion 94 of the second member 52 is inserted into the peripheral wall 90 of the first member 50, and the inner circumferential projection 100 of the first member 50, which protrudes from the inner circumferential surface of the peripheral wall 90, and the outer circumferential projection 102 of the second member 52, which protrudes from the outer circumferential surface of the cylindrical wall portion 94, are locked together in the front-rear direction. In such a connection structure, the second member 52 can be removed from the first member 50 by releasing the lock between the inner circumferential projection 100 and the outer circumferential projection 102, for example, by expanding the diameter of the peripheral wall 90 of the first member 50 or shrinking the diameter of the cylindrical wall portion 94 of the second member 52. The detachable connecting structure between the first member 50 and the second member 52 is not limited to the structures illustrated in Figures 8 to 11. Specifically, for example, connections can be made by fitting recesses (including grooves and through holes) and protrusions provided on one side of the peripheral wall 90 and the cylindrical wall portion 94, by a screw structure, or by frictional resistance through fitting of the cylindrical wall portion 94 to the peripheral wall 90.

[0097] As shown in Figures 11A and 11B, the rear end of the cylindrical wall portion 94 of the second member 52 is pressed against the plate-shaped portion 40 of the filter unit 10 from the front, and the plate-shaped portion 40 is sandwiched between the plate contact portion 92 of the first member 50 and the cylindrical wall portion 94 of the second member 52. As a result, the overlapping surfaces of the plate contact portion 92 of the first member 50 and the plate-shaped portion 40 of the filter unit 10 are airtightly sealed, preventing outside air from bypassing the filter member 12 and entering the inner circumference of the contact body 88. The cylindrical wall portion 94 of the second member 52 is provided with a position-defining portion 104 that protrudes outward, and the relative position of the first member 50 and the second member 52 in the front-rear direction is defined by the position-defining portion 104 contacting the front end of the peripheral wall 90 of the first member 50, so that the compressive force acting on the plate-shaped portion 40 (amount of compressive deformation of the plate-shaped portion 40) is appropriately set.

[0098] In the filter unit 10, the plate-shaped portion 40 of the support 14 is sandwiched between the first member 50 and the second member 52, while the portion other than the plate-shaped portion 40 is separated from the first member 50 and the second member 52. In particular, the plate contact portion 92 of the first member 50 is positioned at a distance on the outer circumference relative to the filter member 12, and the front wall portion 96 of the second member 52 is positioned at a distance in front of the filter member 12. This efficiently ensures the effective surface area of ​​the filter member 12.

[0099] As described above, a face contact 88 is attached to the rear end of the filter support member 48 that houses the filter unit 10. The face contact 88 is made of rubber, resin elastomer, or the like, and is softer and more flexible than the filter support member 48, and an elastic material is preferably used. The face contact 88 is annular in shape so that it fits snugly around the mouth of the mask wearer's face when the mask is worn. When the facepiece 86 is half-face type, the face contact 88 is shaped so that the nose and mouth are located on the inner circumference of the face contact 88 and the eyes are located on the outer circumference of the face contact 88. When the facepiece 86 is full-face type, the face contact 88 is shaped so that the nose, mouth and eyes are all located on the inner circumference of the face contact 88. When the mask is worn, the face contact 88 has flexibility to follow the curvature and unevenness of the mask wearer's face, as well as elasticity to maintain a snug fit to the mask wearer's face.

[0100] The facepiece 88 is connected to the rear end of the peripheral wall 90 of the first member 50 of the filter support member 48 in an airtight, sealed manner. The connection structure between the filter support member 48 and the facepiece 88 is not particularly limited, but for example, a facepiece connection structure 108 using a ring member 106 as shown in Figures 14 and 15 can be adopted. The facepiece connection structure 108 is a connection structure in which the filter support member 48 and the facepiece 88 are connected in an airtight, sealed manner around the entire circumference by pressing the ring member 106 from behind against the front end of the facepiece 88 which is superimposed on the rear end of the filter support member 48, and sandwiching the front end of the facepiece 88 between the filter support member 48 and the ring member 106, while fixing the filter support member 48 and the ring member 106 by means of welding or other means. Thus, by not directly fixing the face contact body 88 to the filter support member 48, but instead sandwiching the face contact body 88 between the mutually fixed filter support member 48 and ring member 106, it is possible to ensure the connection strength between the filter support member 48 and the face contact body 88 while greatly increasing the freedom in selecting the respective forming materials for the filter support member 48 and the face contact body 88. Furthermore, variations in sealing performance due to welding quality between the filter support member 48 and the face contact body 88 are avoided, and excellent sealing performance can be stably obtained.

[0101] A band 84 is attached to the filter support member 48. The band 84 is in the shape of a strip or string, and preferably has elasticity to reduce the load when worn. The band 84 is inserted through a band insertion portion 110 provided on the filter support member 48. The band insertion portion 110 is preferably provided on both the left and right sides of the filter support member 48, as shown in Figures 12 and 13, for example, at the rear end of the first member 50. The left and right bands 84, 84 inserted through the band insertion portion 110 are releasably connected around the wearer's head and neck, so that the mask body 82 is attached to the wearer's face in a removable manner. The means of connecting the left and right bands 84, 84 are not particularly limited, and the left and right bands 84, 84 may be connected by tying them together, or a connecting structure such as a buckle may be provided on the left and right bands 84, 84 in advance. Furthermore, the bands 84 inserted through the left and right band insertion sections 110, 110 may be integrally connected. In this case, for example, by actively employing elastic bands 84, ease of attachment and positioning and holding function of the mask body 82 can be achieved.

[0102] Then, when the mask body 82 is fitted to cover the mouth and nose of wearer A, outside air that enters the filter support member 48 through the ventilation holes 98 in the front wall portion 96 of the second member 52 is filtered by the filter member 12 and moves into the facepiece 88, where it is inhaled by wearer A. As a result, foreign matter such as viruses and dust in the outside air is removed by the filter member 12, providing wearer A with clean air. In particular, by adopting the filter unit 10, it is possible to achieve both high filtering performance capable of capturing minute particles such as viruses and reduced breathlessness for wearer A, while keeping the size of the mask 80 small, and thus effectively obtain the effects of the filter unit 10, such as obtaining excellent infection prevention effects continuously over a long period of time.

[0103] Furthermore, the filter unit 10 shown in the first embodiment can also be used as a filter unit for a reusable mask. When reusing the filter unit 10, for example, it is necessary to clean the filter member 12 by reducing the bacteria and viruses attached to the filter member 12 of the used filter unit 10.

[0104] Specifically, for example, bacteria and viruses are reduced by spraying disinfectant onto the filter member 12. The disinfectant is a liquid used to kill bacteria and viruses, and is not particularly limited, but disinfectants such as alcohol and sodium hypochlorite, or hypochlorous acid water are preferably used. Furthermore, the conditions for spraying the disinfectant and subsequent processing can be appropriately set depending on the disinfectant used. It is also possible to use UV sterilization by irradiating with ultraviolet light to disinfect the filter member 12, but spraying disinfectant is preferred because it requires less equipment and a simpler process.

[0105] However, disinfection by spraying disinfectant solution has the problem of being prone to variability and inconsistent effectiveness compared to methods such as directly wiping with a disinfectant cloth soaked in disinfectant solution. On the other hand, when wiping the filter directly with a disinfectant cloth, the filter must be smoothed, which reduces the effective area and leads to a decrease in breathability. Therefore, the filter unit 10 for reusable masks has a frame portion height H of 20 mm or more, preferably 25 mm or more, and the inner dimension W of the frame portion 30 (the maximum distance between opposing inner surfaces of the frame portion 30) is 2.5 times or less, preferably 2 times or less, the axial height H of the frame portion 30. As a result, the frame portion 30 in this embodiment is in the shape of a long, narrow cylinder. As a result, the sprayed disinfectant is more likely to remain within the frame 30, allowing for efficient spatial disinfection within the frame 30. This also helps to induce disinfection even in areas where the spray does not directly adhere (the ends of the pleated filter in the continuous or widthwise direction, the opposite side facing the spray, the vicinity of the frame 30, and the vicinity of the corners). By focusing on the novel aspect of spatial disinfection in mask filters in this way, the entire filter can be efficiently disinfected, making it possible to create a reusable mask that was previously unavailable. The height dimension H of the frame 30 is preferably 50 mm or less. This prevents the filter mounting section (described later) that houses the filter unit 10 from protruding significantly forward from the face when wearing a reusable mask equipped with the filter unit 10, thus ensuring a good field of view by minimizing obstruction of vision.

[0106] Furthermore, in the filter unit 10 for reusable masks, the height dimension H of the frame portion 30 is greater than the height dimension h of the filter member 12 housed within the inner circumference of the frame portion 30, and preferably, both axial ends of the frame portion 30 protrude axially outward from the filter member 12. In short, the filter member 12 is housed within the inner circumference of the frame portion 30 without protruding from it.

[0107] Then, when disinfectant is sprayed from the outside in the axial direction onto the filter member 12 housed in the elongated cylindrical frame 30, the disinfectant, now in the form of fine spray particles (including vaporized material), adheres to the surface of the filter member 12, killing and reducing bacteria, viruses, etc. that have adhered to the surface of the filter member 12. The internal space of the frame 30 housing the filter member 12 has a relatively small opening area to the outside and a large axial height. Therefore, the spray particles of disinfectant sprayed towards the filter member 12 inside the frame 30 have difficulty escaping from the internal space of the frame 30 and tend to remain inside the frame 30. As a result, the spray particles of disinfectant remain inside the internal space of the frame 30 and diffuse within that space, increasing the number of spray particles that adhere to the surface of the filter member 12, thus effectively disinfecting the entire surface of the filter member 12.

[0108] Furthermore, if a structure is adopted in which multiple flat filter sections are stacked and spaced apart from each other in order to increase the effective area and improve ventilation, it becomes difficult to directly spray disinfectant into the depths of the narrow gaps between the filter sections. However, in the filter member 12 of this embodiment, the folded structure has a pleated shape with continuous peaks and valleys, and the gaps between the peaks and valleys widen outward. As a result, disinfectant sprayed from the outside can easily reach the depths of the gaps, making it easy to directly spray disinfectant over almost the entire filter surface. Moreover, by allowing fine spray particles of disinfectant to float in the internal space of the frame 30, the disinfectant penetrates almost evenly to the bottom of the deep valleys of the filter member 12, and the desired disinfecting effect can be stably obtained over the entire surface, including narrow areas such as the valleys of the pleats.

[0109] Furthermore, since the filter member 12 of this embodiment is equipped with a bead portion 28 that holds the peaks and valleys of the pleats, the gaps between the folded peaks and valleys are held by the bead portion 28, preventing the gaps between the peaks and valleys from narrowing or collapsing locally, and allowing the entire surface of the peaks and valleys to be disinfected with the disinfectant solution more stably.

[0110] The filter sheet 16 constituting the filter member 12 is preferably made of nonwoven fabric on at least the surface (more preferably both sides) on the side to which the disinfectant is sprayed when the disinfectant is sprayed from only one side. Because nonwoven fabric has countless fine fibers protruding from its surface, the spray particles of disinfectant floating inside the frame 30 are easily captured by these protruding fine fibers, and the spray particles of disinfectant adhere to the surface of the filter sheet 16, thereby advantageously obtaining a disinfecting effect.

[0111] Although we have described the case of making a medical filter unit 10 into a reusable filter unit, filter units intended for non-medical use can also be similarly made into reusable filter units for masks.

[0112] Furthermore, the filter unit 10 constitutes the mask by being housed in a filter attachment portion provided on the facepiece of the mask, for example, in the mask shown in Japanese Patent Application Publication No. 2002-239018. In particular, if the filter unit 10 is a filter unit for a reusable mask, a reusable mask that can be used multiple times can be obtained. The filter unit 10 may be detachably attached to the filter attachment portion of the mask, or it may be fixedly attached to the filter attachment portion. In the case of a reusable mask, if the filter unit 10 is detachably attached to the filter attachment portion, disinfectant may be sprayed onto the filter member 12 after it has been removed from the filter attachment portion, or disinfectant may be sprayed onto the filter member 12 through the air intake hole or the like of the filter attachment portion while it is still attached to the mask.

[0113] Experiments have confirmed that spraying disinfectant onto the filter element 12 in the filter unit 10 is effective in suppressing the growth of attached bacteria. The experiment was conducted under the assumption of reusing a reusable mask equipped with the filter unit 10, and the disinfection effect was confirmed by the number of Staphylococcus aureus colonies.

[0114] Specifically, first, Staphylococcus aureus (manufactured by Microbiologics, Inc., strain ATCC6538) that has been subcultured for two generations is placed in one MacFarland tray (3 × 10⁻¹⁴). 8 The bacterial solution is prepared by suspending the bacteria in sterile water for injection to a concentration of FCU / mL. Next, using a spray bottle (manufactured by Maruichi Co., Ltd., product name: Mini Trigger Pump), the prepared bacterial solution is sprayed once from the front of the reusable mask at a spray rate of 0.28 mL / spray towards the area where the filter unit 10 is located. Next, the reusable mask sprayed with the bacterial solution is dried for about 4 hours in a sterile environment at a temperature of 20°C to 25°C and a relative humidity of approximately 50% RH. Using the spray bottle described above, the test solution (five types of test solutions: "no test solution" (control), "sterile water for injection", "30 ppm hypochlorous acid water", "83 vol% ethanol", and "70 vol% isopropanol") is sprayed five times from the front of the dried reusable mask at a spray rate of 0.28 mL / spray towards the area where the filter unit 10 is located. At the same time, the test solution is sprayed once each at a spray rate of 0.28 mL / spray towards the four sides of the frame 30 using the same spray bottle. Next, the reusable masks were left standing for 3 minutes in a sterile environment with a temperature of 20°C to 25°C and a relative humidity of approximately 50% RH, under no airflow. Then, they were placed in a sterile bag containing 20 mL of inactivation solution (an aqueous solution containing 0.5% sodium thiosulfate, 3% lecithin, and 10% polysorbate 80) and kneaded by hand for 1 minute to extract Staphylococcus aureus. Finally, a 10-fold dilution series of the extract was prepared using sterile water for injection, and the samples were cultured on SCD agar medium (manufactured by Merck KGaA, product name Tryptic Soy Agar-ICR 30 ml) at 37°C for 2 days, after which the number of colonies was counted.

[0115] The results of these experiments are shown in Tables 1 and 2 below. Table 1 shows the number of viable Staphylococcus aureus bacteria in experiments using each test solution, and Table 2 shows the logarithmic decrease in Staphylococcus aureus when using other test solutions, with the case where no test solution was sprayed serving as the control.

[0116] [Table 1]

[0117] [Table 2]

[0118] According to the experimental results in Tables 1 and 2, Staphylococcus aureus was most abundant in the control group. When sterile water for injection was sprayed as the test solution, the number of viable bacteria decreased slightly compared to the control group, but it was still high. On the other hand, when 30 ppm hypochlorous acid water, 83 vol% ethanol, and 70 vol% isopropanol were used as test solutions, it was confirmed that Staphylococcus aureus was significantly reduced in a short time, making disinfection possible. The sterilization rate in Table 2 is calculated as (average number of viable bacteria in the control group - number of viable bacteria) / average number of viable bacteria in the control group × 100.

[0119] Although embodiments of the present invention have been described in detail above, the present invention is not limited by its specific description. For example, the number of peaks and valleys in the folded filter member 12 can be appropriately set according to the required air permeability and collection efficiency. The inclined portion 21 of the filter member 12 does not necessarily have to be a straight, flat shape; for example, it may be curved or bent. In particular, the inclined portion 21 is part of the filter sheet 16 that can be folded, and changes and variations in shape can occur relatively easily. Therefore, even if the inclined portion 21 is designed to be a straight, flat shape, curvature or the like can occur. Consequently, the multiple peaks and valleys may not necessarily be the same shape as each other, and variations in shape can occur.

[0120] In the filter member 12, the number of bead portions 28 can be changed as needed. Specifically, for example, to further improve the shape stability of the filter member 12, three or more bead portions 28 may be provided, or the effective area of ​​the filter sheet 16 can be increased by having one bead portion 28 or by eliminating it. Furthermore, the position where the bead portions 28 are formed is not limited; for example, they may be provided in the center of the filter member 12 in the left-right direction.

[0121] The frame portion 30 is not limited to a rectangular tube shape, but may be cylindrical, polygonal tubes other than rectangular, or irregularly shaped tubes. Furthermore, it is desirable that the outer circumferential shape of the filter member 12 corresponds to the shape of the frame portion 30.

[0122] In the above embodiment, a support 14 in which a frame portion 30, a plate-shaped portion 40, and a sealing portion 42 are integrally formed was illustrated, but the support 14 may also have a structure made up of multiple parts. Specifically, a plate-shaped portion 40 made of an elastic material may be fixed to a rigid frame portion 30, or the frame portion 30 and the plate-shaped portion 40 may be made of rigid material, and an O-ring-shaped sealing portion made of an elastic material may be disposed on the rear surface of the plate-shaped portion 40. The frame portion 30, the plate-shaped portion 40, and the sealing portion 42 may also be formed separately, and the support 14 can be formed by fixing these frame portion 30, plate-shaped portion 40, and sealing portion 42 together.

[0123] The plate-shaped portion 40, which includes the sealing portion 42, may be provided in the middle of the frame portion 30 in the axial direction. Alternatively, for example, the plate-shaped portion 40 may be omitted, and a rib-shaped sealing portion may be provided that protrudes around the entire circumference of the rear surface of the frame portion 30, so that the rear surface of the frame portion 30 is pressed against the filter support member 48, thereby sealing the space between the support 14 and the filter support member 48.

[0124] The sealing portion 42 is preferably annular in shape to prevent variations in sealing performance in the circumferential direction, but it may also be a polygonal annular or irregularly shaped annular. Furthermore, a sealing lip 43 is not essential for the sealing portion 42.

[0125] In the above embodiment, the groove-shaped portion 44 was formed in the plate-shaped portion 40, but the groove-shaped portion 44 may open on the rear surface of the frame portion 30. The groove-shaped portion 44 may be provided between the upper and lower injection port marks 45, 45 and the filter member 12. The groove-shaped portion 44 may be an annular groove that is continuous in the circumferential direction of the frame portion 30. In addition, the injection port marks 45 may be formed on the rear surface of the frame portion 30 in the same way as the groove-shaped portion 44, in which case the groove-shaped portion 44 is provided to open on the rear surface of the frame portion 30 at an inner circumference than the injection port marks 45. The number of injection port marks 45 and their arrangement in the circumferential direction can be appropriately changed according to the molding conditions of the support 14, etc.

[0126] The filter unit 10 does not necessarily have to be separate from the facepiece of the mask; for example, the support 14 of the filter unit 10 may also serve as the facepiece of the mask. In this case, in order to attach the support 14 to the user's face in a close fit, the user-side attachment portion of the support 14 is molded to an appropriate shape, and a string or the like is provided on the support 14 at this user-side attachment portion to hold the support 14 in place on the user's face.

[0127] The present invention is suitably applied to medical masks for preventing viral infections. It can also be used in other medical fields, such as ventilators. For example, the present invention can be used in artificial noses, solving the problem of reduced breathability due to pressure loss, a common issue in the field of artificial noses.

[0128] As shown in Figures 6 to 9, the plate-shaped portion 40 has a roughly rectangular inner circumference and a roughly circular outer circumference, and is provided with a pair of groove-shaped portions 44, 44 that open on the rear surface, are located on both the left and right sides, and extend linearly in the vertical direction. The plate-shaped portion 40 is plate-like and protrudes from the rear end of the frame portion 30 outwards, so it is recognized as a single, cohesive part in terms of design. Furthermore, the plate-shaped portion 40 has the specific function of airtightly attaching the frame portion 30 that holds the filter member 12 to the filter support member 48. It is connected to the frame portion 30 at its roughly rectangular inner circumference and achieves an airtight connection to the filter support member 48 at its roughly circular outer circumference, while also miniaturizing the filter support member 48. In addition, the plate-shaped portion 40 has a seal lip 43 on its outer circumference, enabling sealing without the need for separate parts such as O-rings. Note that the pair of groove-shaped portions 44, 44 are not essential as design elements.

[0129] Furthermore, as shown in Figures 6 to 9, the support 14 has a frame portion 30 that is roughly rectangular in shape, which is integrally provided with a plate-shaped portion 40 that has a circular outer shape and a roughly rectangular inner shape, with the frame portion 30 protruding forward from the inner circumferential end of the plate-shaped portion 40. In addition, multiple rib-shaped portions 34 are provided in the circumferential direction of the frame portion 30, protruding from the outer circumferential surface of the frame portion 30 and extending in the front-rear direction, which is the axial direction of the frame portion 30. The support 14 integrally comprises the frame portion 30, the plate-shaped portion 40, and the rib-shaped portions 34, and the whole can be recognized as a single component with a cohesive design. Moreover, the support 14 is a component that has the specific function of connecting the filter member 12 and the filter support member 48, and the frame portion 30 reinforced by the rib-shaped portions 34 holds the outer circumferential end of the filter member 12 airtightly, while the plate-shaped portion 40 with a circular outer shape allows for airtight attachment to the filter support member 48 while miniaturizing the filter support member 48. Furthermore, the support 14 has attracted attention because, unlike conventional support 14 which consisted only of a frame portion 30 for holding the filter member 12, it integrally comprises a substantially rectangular cylindrical frame portion 30, rib-shaped portions 34 protruding from the outer surface of the frame portion 30, and a plate-shaped portion 40 having a substantially rectangular inner shape corresponding to the frame portion 30 and a substantially circular outer shape not corresponding to the frame portion 30. [Explanation of Symbols]

[0130] 10 Medical filter units 12 Filter component 14 Support 16 filter sheets 20 Top 21 Slope 22 First edge 24 Second edge 26 Fixing piece 28 Bead section 30 Frame section 32 Intake holes 34 Rib-shaped section 36 Fixed protrusion 38 Step surface 40 Plate-shaped part 42 Seal part 43 Seal Lip 44 Groove 45 Inlet trace 46. ​​Attachment end 48 Filter support member (main body member) 50 First Member 52 Second Member 54 Containment Depression 56 Clamping part 58. First seal structure 60. Second seal structure 80 masks 82 Mask body 84 bands 86-sided polyhedron 88 Face Contact Body 90 Peripheral wall 92 Plate contact area 94 Cylindrical wall section 96 Front wall 98 Ventilation holes 100 Inner peripheral protrusion 102 Outer peripheral projection 104 Position specifying section 106 Ring member 108-sided polyhedron connecting structure 110 Band insertion section A. Wearer

Claims

1. A filter component, equipped with a filter sheet, is housed in a cylindrical frame provided on a resin support attached to the main body component. The filter sheet is folded back to form a pleated shape with multiple peaks and valleys, A medical filter unit in which the first end edges of the filter sheet on both sides in the continuous direction of the peaks and valleys, and the second end edges of the filter sheet extending in a zigzag pattern on both sides in the width direction of the peaks and valleys, are each embedded and fixed to the frame along their entire length, so that the entire circumference of the filter sheet is embedded and fixed to the frame.

2. The medical filter unit according to claim 1, wherein the second edge of the filter sheet is provided with a fixing end that is inclined in the circumferential direction of the frame and fixed to the frame in an embedded state.

3. The medical filter unit according to claim 1 or 2, wherein the first edge of the filter sheet is provided with a fixing piece that is folded back and fixed to the frame in an embedded state.

4. A filter component, equipped with a filter sheet, is housed in a cylindrical frame provided on a resin support attached to the main body component. The filter sheet is folded back to form a pleated shape with multiple peaks and valleys, The filter sheet is provided with bead portions that extend in the continuous direction of the peaks and valleys and hold the peaks and valleys, The frame portion is a medical filter unit having a fixing projection that protrudes toward the bead portion and is fixed to the bead portion.

5. A method for manufacturing a medical filter unit, wherein a filter member equipped with a filter sheet is housed in a cylindrical frame provided on a resin support attached to a main body member, The first step is to set the filter member, which has bead portions that hold the peaks and valleys in the filter sheet that is folded back in a pleated shape with multiple peaks and valleys connected together, into the molding die of the support, A second step involves positioning the first end edges of the filter sheet, located on both sides in the continuous direction of the peaks and valleys, and the second end edges of the filter sheet, located on both sides in the width direction of the peaks and valleys and extending in a zigzag pattern, within the cavity of the molding die, and then filling the cavity of the molding die with a resin material to form the support, thereby forming a frame portion of the support to which the filter sheet is fixed around its entire circumference. A method for manufacturing a medical filter unit that includes the above.

6. A filter component, equipped with a filter sheet, is housed in a cylindrical frame provided on a resin support attached to the main body component. The filter sheet is folded back to form a pleated shape with multiple peaks and valleys, The support is provided with a plate-shaped portion that extends from the axial end of the frame portion outwards, and the injection port for the resin material is located on this plate-shaped portion. A medical filter unit in which a groove-shaped portion is formed at the end face of the support on which the plate-shaped portion is formed, located on the inner circumference side of the injection port and extending in the circumferential direction of the frame portion.

7. A filter component, equipped with a filter sheet, is housed in a cylindrical frame provided on a resin support attached to the main body component. The filter sheet is folded back to form a pleated shape with multiple peaks and valleys, The support is made of an elastic material, A medical filter unit comprising a support body, wherein a sealing portion is integrally formed with the frame portion, surrounding the entire outer circumference of the frame portion and being compressed by the main body member.

8. A medical filter unit according to claim 7, comprising: a first seal structure in which the sealing portion is sandwiched by the main body member, thereby sealing the space between the support and the main body member in the direction in which the sealing portion is sandwiched by the main body member; and a second seal structure in which the space between the support and the main body member is sealed in a direction intersecting the direction in which the sealing portion is sandwiched by the main body member.

9. A filter component, equipped with a filter sheet, is housed in a cylindrical frame provided on a resin support attached to the main body component. The filter sheet is folded back to form a pleated shape with multiple peaks and valleys, The first end edges of the filter sheet on both sides in the continuous direction of the peaks and valleys, and the second end edges of the filter sheet extending in a zigzag pattern on both sides in the width direction of the peaks and valleys, are each fixed to the frame along their entire length, so that the entire circumference of the filter sheet is fixed to the frame. A medical filter unit in which both ends of the frame in the axial direction protrude outward in the axial direction from the filter member.

10. A filter component, equipped with a filter sheet, is housed in a cylindrical frame provided on a resin support attached to the main body component. The filter sheet is folded back to form a pleated shape with multiple peaks and valleys, A medical filter unit in which the frame is made of an elastic material, and rib-like portions protruding from the outer circumferential surface of the frame and extending in the axial direction of the frame are integrally formed with the frame.

11. A filter member, which has a pleated filter sheet that is folded back to form multiple peaks and valleys, is housed in a polygonal cylindrical frame provided on a resin support attached to the main body member. The support is provided with a plate-shaped portion that extends from the frame portion outwards, A medical filter unit in which the plate-shaped portion has resin material injection port marks located on the outer circumference of each side of the frame portion.

12. A filter component is placed inside a cylindrical frame that is impermeable to fluids. The filter sheet constituting the filter member is folded back to form a pleated shape with multiple peaks and valleys. The height of the frame is greater than the height of the filter member. The height dimension of the frame is 20 mm or more, and A filter unit for reusable masks in which the internal dimensions of the frame are set to be 2.5 times or less the height dimension.

13. A reusable mask comprising a filter unit for a reusable mask as described in claim 12.

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