filter

Abstract

The filter of the present application includes: a filter base portion having a first main surface and a second main surface on the opposite side of the first main surface, a plurality of through holes being formed to communicate the first main surface and the second main surface; and a support portion disposed on the filter base portion, the support portion including: a main body portion disposed on the first main surface, having a plurality of fixing portions disposed on the plurality of through holes; and a protruding portion protruding from a fixing portion of the plurality of fixing portions on the side wall side of the main body portion toward the outside of the main body portion in the direction along the first main surface, the thickness of the protruding portion being smaller than the thickness of the main body portion.

Description

Technical Field

[0001] This invention relates to filters. Background Technology

[0002] Patent Document 1 discloses a mesh member having mesh openings and an outer frame. The mesh openings have recesses for capturing particles and holes formed in the recesses, and the outer frame fixes the outer periphery of the mesh openings. In the mesh member of Patent Document 1, a strip-shaped support frame is provided across the opposite frame edge of the outer frame, and the strip-shaped support frame is embedded across the recesses and holes connected to the recesses.

[0003] Prior art literature

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-181352 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] However, in the mesh component of Patent Document 1, there is still room for improvement in preventing clogging.

[0008] The purpose of this invention is to provide a filter that can prevent clogging.

[0009] means for solving problems

[0010] A filter according to one aspect of the present invention comprises: a filter base having a first main surface and a second main surface opposite to the first main surface, and having formed a plurality of through holes communicating between the first main surface and the second main surface; and a support portion disposed on the filter base, the support portion comprising: a main body disposed on the first main surface, having a plurality of fixing portions disposed on the plurality of through holes; and a protrusion protruding from a fixing portion located on the sidewall side of the main body among the plurality of fixing portions toward the outside of the main body in a direction along the first main surface, the thickness of the protrusion being less than the thickness of the main body.

[0011] Invention Effects

[0012] According to the present invention, a filter capable of preventing clogging can be provided. Attached Figure Description

[0013] Figure 1 This is a schematic diagram showing an example of the filter of Embodiment 1 of the present invention viewed from the first main surface side.

[0014] Figure 2 This is a schematic diagram showing an example of the filter of Embodiment 1 of the present invention viewed from the second main side.

[0015] Figure 3AThis is an enlarged perspective view of a part of the filter substrate.

[0016] Figure 3B yes Figure 3A A cross-sectional view at line AA.

[0017] Figure 4 This is an enlarged view of a portion of the filter base with a support.

[0018] Figure 5 yes Figure 4 A cross-sectional view at line BB.

[0019] Figure 6A This is a schematic diagram illustrating an example of the manufacturing process of the filter according to Embodiment 1 of the present invention.

[0020] Figure 6B This is a schematic diagram illustrating an example of the manufacturing process of the filter according to Embodiment 1 of the present invention.

[0021] Figure 6C This is a schematic diagram illustrating an example of the manufacturing process of the filter according to Embodiment 1 of the present invention.

[0022] Figure 6D This is a schematic diagram illustrating an example of the manufacturing process of the filter according to Embodiment 1 of the present invention.

[0023] Figure 6E This is a schematic diagram illustrating an example of the manufacturing process of the filter according to Embodiment 1 of the present invention.

[0024] Figure 6F This is a schematic diagram illustrating an example of the manufacturing process of the filter according to Embodiment 1 of the present invention.

[0025] Figure 6G This is a schematic diagram illustrating an example of the manufacturing process of the filter according to Embodiment 1 of the present invention.

[0026] Figure 7 This is a cross-sectional view showing a portion of the filter according to Embodiment 1 of the present invention.

[0027] Figure 8A This is an enlarged cross-sectional view of the support portion of a modified embodiment 1 of the present invention.

[0028] Figure 8B This is an enlarged cross-sectional view of the support portion of a modified embodiment 1 of the present invention.

[0029] Figure 9 This is an enlarged cross-sectional view of the support portion of a modified embodiment 1 of the present invention. Detailed Implementation

[0030] (The process of realizing this invention)

[0031] It is known that filters, such as the mesh component described in Patent Document 1, have a support portion provided in the filter base with multiple through holes in order to improve strength.

[0032] However, in filters with such supports, there is still room for improvement in preventing clogging. For example, near the support, there are incomplete through-holes that are partially blocked by the support. In this specification, "incomplete" means having a size smaller than the designed size, taking into account manufacturing errors. When the filtered material enters such an incomplete through-hole and causes clogging, the recovery of the filtered material becomes difficult. Furthermore, in the case of cells being filtered, the clogged cells dry and die on the filter substrate, making the recovery of surviving cells difficult.

[0033] Therefore, in order to solve the above-mentioned problems, the inventors discovered a filter comprising a main body and a support portion with a protrusion disposed within a through hole, thus realizing the present invention. As a result, clogging caused by the filtered material can be prevented in the through hole near the support portion. Furthermore, liquid accumulation can be formed near the support portion to suppress the drying of the filtered material, and in the case where the filtered material is cells, the death of the filtered material can be prevented.

[0034] A filter according to one aspect of the present invention comprises: a filter base having a first main surface and a second main surface opposite to the first main surface, and having formed a plurality of through holes communicating between the first main surface and the second main surface; and a support portion disposed on the filter base, the support portion comprising: a main body disposed on the first main surface, having a plurality of fixing portions disposed on the plurality of through holes; and a protrusion protruding from a fixing portion located on the sidewall side of the main body among the plurality of fixing portions toward the outside of the main body in a direction along the first main surface, the thickness of the protrusion being less than the thickness of the main body.

[0035] This structure reduces the opening area of ​​incomplete through holes, preventing filter clogging caused by the filtered material.

[0036] In the filter of the second aspect of this disclosure, the filter base may have an inner wall extending from the second main surface toward the first main surface and defining a plurality of through holes, and the protrusion contacts the inner wall of the through hole where a fixing part located on the side wall side of the main body is disposed.

[0037] This structure further prevents filter clogging caused by the objects being filtered.

[0038] In the third-party filter disclosed herein, the protrusion may also have a surface continuous with the first main surface.

[0039] This structure prevents the filtered material from entering the through-holes near the support.

[0040] In the fourth type of filter disclosed herein, the protrusion may also have a shape that protrudes from the first main surface toward the second main surface.

[0041] With this structure, it is possible to prevent the filter material from entering the through holes near the support and to promote the movement of the material that needs to be separated from the filter material to other through holes.

[0042] In the fifth type of filter disclosed herein, the thickness of the protrusion at the position where it contacts the main body may be greater than the thickness of the protrusion at the position where it contacts the inner wall.

[0043] This structure further facilitates the movement of substances that need to be separated from the filtered object into the through-holes.

[0044] In the sixth aspect of the filter disclosed herein, the protrusion may also have a shape that is recessed relative to the first main surface from the first main surface toward the second main surface.

[0045] This structure allows for the formation of liquid accumulation near the support, thus inhibiting the drying of filtered materials such as cells.

[0046] In the filter of the seventh aspect of this disclosure, the protrusion may seal the through hole of the fixing part located on the side wall side of the main body.

[0047] This structure further prevents filter clogging caused by the objects being filtered.

[0048] In the filter of the eighth aspect of this disclosure, the main body may have a first sidewall and a second sidewall opposite to the first sidewall, and the protrusion is provided on the fixing part located on the first sidewall and the second sidewall of the main body respectively.

[0049] This structure further prevents filter clogging caused by the objects being filtered.

[0050] In the filter of the ninth aspect of this disclosure, the support portion may also have: a plurality of first support members having a main body and a protrusion and extending along a first direction; and a plurality of second support members having a main body and a protrusion and extending along a second direction intersecting the first direction.

[0051] This structure can improve the strength of the filter.

[0052] Hereinafter, Embodiment 1 of the present invention will be described with reference to the accompanying drawings. Furthermore, in each drawing, the elements are shown in exaggerated form for ease of explanation.

[0053] (Implementation Method 1)

[0054] [Overall Structure]

[0055] Figure 1 This is a schematic diagram showing an example of the filter 1 of Embodiment 1 of the present invention as viewed from the first main surface PS1 side. Figure 2 This is a schematic diagram of an example of the filter 1 according to Embodiment 1 of the present invention, viewed from the second main surface PS2 side. In the figure, the X, Y, and Z directions represent the longitudinal, transverse, and thickness directions of the filter 1, respectively.

[0056] For example, filter 1 is a filter that filters the fluid containing the object to be filtered.

[0057] In this specification, "filterable material" refers to the material to be filtered from the fluid. For example, the filterable material can also be biologically derived substances contained in the fluid. "Biologically derived substances" refers to substances derived from living organisms, such as cells (eukaryotes), bacteria (eubacteria), and viruses. Examples of cells (eukaryotes) include, for example, induced pluripotent stem cells (iPS cells), ES cells, stem cells, mesenchymal stem cells, monocytes, single cells, cell clusters, planktonic cells, adherent cells, nerve cells, white blood cells, cells for regenerative medicine, autologous cells, cancer cells, circulating cancer cells (CTCs), HL-60, HELA, and bacteria. Examples of bacteria (eubacteria) include, for example, Escherichia coli and Mycobacterium tuberculosis.

[0058] As a fluid, for example, liquids or gases. As a liquid, for example, cell suspensions.

[0059] Filter 1 is a metal filter. The material constituting filter 1 is primarily composed of at least one of metals and metal oxides. For example, the material constituting filter 1 may also be gold, silver, copper, platinum, nickel, palladium, titanium, their alloys, and their oxides. In particular, by using titanium or nickel-palladium alloys, less metal leaching occurs, reducing the impact on the filtered material.

[0060] like Figure 1 and Figure 2 As shown, the filter 1 has a filter portion 10 and a frame portion 20 disposed on the outer periphery of the filter portion 10. Furthermore, the filter 1 has a first main surface PS1 and a second main surface PS2 on the side opposite to the first main surface PS1. In Embodiment 1, the filter portion 10 and the frame portion 20 are integrally formed.

[0061] <Filter Department>

[0062] The filter section 10 is a section that filters fluid including the object to be filtered. The filter section 10 includes a filter base section 12 having a plurality of through holes 11 that communicate with a first main surface PS1 and a second main surface PS2. In addition, in the filter section 10, a plurality of support portions 13 are disposed on the first main surface PS1 of the filter base section 12.

[0063] The shape of the filter section 10, when viewed from the thickness direction (Z direction) of the filter 1, is, for example, circular, polygonal, or elliptical. In Embodiment 1, the shape of the filter section 10 is approximately circular. It should be noted that, in this specification, "approximately circular" means that the ratio of the length of the major axis to the length of the minor axis is 1.0 or more and 1.2 or less.

[0064] <Frame>

[0065] The frame portion 20 is provided on the outer periphery of the filter portion 10, and is the portion with fewer through holes 11 per unit area than the filter portion 10. The number of through holes 11 in the frame portion 20 is less than 1% of the number of through holes 11 in the filter portion 10. The thickness of the frame portion 20 may also be thicker than the thickness of the filter portion 10. With this structure, the mechanical strength of the filter 1 can be improved.

[0066] When the filter 1 is connected to the device, the frame portion 20 can also function as a connection portion for connecting the filter 1 to the device. In addition, information about the filter 1 (such as the size of the through hole 11) can be displayed on the frame portion 20.

[0067] The frame portion 20 is formed in a ring shape when viewed from the first main surface PS1 side of the filter portion 10. When the filter 1 is viewed from the first main surface PS1 side, the center of the frame portion 20 coincides with the center of the filter portion 10. That is, the frame portion 20 and the filter 1 are formed on concentric circles.

[0068] The filter section 10 will be described in detail below.

[0069] Figure 3A This is an enlarged perspective view of a part of the filter section 10. Figure 3A A portion of the filter substrate 12 having a plurality of through holes 11 is shown magnified. Figure 3B yes Figure 3A A cross-sectional view of the filter base 12 at line AA.

[0070] like Figure 3A As shown, a plurality of through holes 11 are periodically arranged on the first main surface PS1 and the second main surface PS2 of the filter section 10. Specifically, the plurality of through holes 11 are arranged in a matrix at equal intervals in the filter section 10.

[0071] In Embodiment 1, when viewed from the first main surface PS1 side (Z direction) of the filter section 10, the plurality of through holes 11 are arranged along two mutually orthogonal directions. Figure 3A The through holes 11 are set in the X and Y directions. It should be noted that multiple through holes 11 can be provided in the filter section 10, and their arrangement direction is not limited.

[0072] like Figure 3A As shown, the filter substrate 12 without through holes 11 is formed in a lattice shape. Specifically, the filter substrate 12 has a plurality of first substrate members 12aa that are equally spaced and extend along a first direction (X direction) in the filter section 10, and a plurality of second substrate members 12ba that are equally spaced and extend along a second direction (Y direction) that intersects the first direction (X direction).

[0073] Multiple first base members 12aa and multiple second base members 12ba are formed from plate-shaped components. Multiple through holes 11 are defined by the intersection of the multiple first base members 12aa and the multiple second base members 12ba. In Embodiment 1, the first direction in which the multiple first base members 12aa extend is the X direction, and the second direction in which the multiple second base members 12ba extend is the Y direction. That is, in Embodiment 1, the first direction and the second direction are orthogonal.

[0074] In embodiment 1, a plurality of first base components 12aa and a plurality of second base components 12ba are integrally formed.

[0075] The filter substrate 12 has a first inner wall 12a, a second inner wall 12b, a third inner wall 12c, and a fourth inner wall 12d extending from the second main surface PS2 toward the first main surface PS1 and defining a plurality of through holes 11. In Embodiment 1, the first inner wall 12a, the second inner wall 12b, the third inner wall 12c, and the fourth inner wall 12d are formed by flat surfaces extending from the second main surface PS2 toward the first main surface PS1 of the filter substrate 12. Figure 3A As shown, the first inner wall 12a and the second inner wall 12b are opposite each other in the Y direction, and the third inner wall 12c and the fourth inner wall 12d are opposite each other in the X direction.

[0076] The thickness T1 of the filter substrate 12 in the filter section 10 is 0.5 μm or more and 20 μm or less. With this structure, pressure loss of the fluid passing through the filter can be reduced while maintaining mechanical strength. Preferably, the thickness T1 of the filter substrate 12 in the filter section 10 is 1.0 μm or more and 3 μm or less. With this structure, pressure loss of the fluid passing through the filter can be further reduced.

[0077] like Figure 3BAs shown, a first opening 11a of the through hole 11 is formed on the first main surface PS1 side of the filter section 10. Additionally, a second opening 11b of the through hole 11 is formed on the second main surface PS2 side of the filter section 10. In Embodiment 1, the first opening 11a and the second opening 11b have a square shape when viewed from the first main surface PS1 side.

[0078] The first opening 11a has a dimension C1, and the second opening 11b has a dimension C2. Dimension C1 of the first opening 11a and dimension C2 of the second opening 11b are representative dimensions in the shape of the openings. In Embodiment 1, dimensions C1 and C2 may also be one side of a square. Alternatively, for example, if the shapes of the first opening 11a and the second opening 11b are circular, dimensions C1 and C2 may also be diameters.

[0079] For example, the size C1 of the first opening 11a and the size C2 of the second opening 11b are 0.5 μm or more and 400 μm or less. Preferably, the size C1 of the first opening 11a and the size C2 of the second opening 11b are 1 μm or more and 30 μm or less. In Embodiment 1, the size C1 of the first opening 11a and the size C2 of the second opening 11b are the same.

[0080] It should be noted that the shapes of the first opening 11a and the second opening 11b are not limited to square shapes. For example, the shapes of the first opening 11a and the second opening 11b can also be circular, elliptical, rectangular, polygonal, etc.

[0081] In the filter section 10, the surface roughness of the first main surface PS1 and the second main surface PS2 is preferably small. Here, surface roughness refers to the average of the differences between the maximum and minimum values ​​measured at any five locations using a stylus-type profilometer. In Embodiment 1, the surface roughness is preferably smaller than the size of the object to be filtered, and more preferably smaller than half the size of the object to be filtered. This is to reduce the adhesion of the object to be filtered, and to enable efficient recovery after the object to be filtered is captured by the filter.

[0082] return Figure 1 A support portion 13 is disposed on the first main surface PS1 of the filter portion 10. In other words, the support portion 13 is disposed on the first main surface PS1 of the filter base portion 12.

[0083] The support portion 13 is formed in a lattice shape. Specifically, the support portion 13 has a plurality of first support members 13a extending along a first direction (X direction) and a plurality of second support members 13b extending along a second direction (Y direction) intersecting the first direction. In Embodiment 1, the first direction is the X direction and the second direction is the Y direction. That is, the plurality of first support members 13a and the plurality of second support members 13b are orthogonal. In addition, in conjunction with the above, in Embodiment 1, the first support members 13a extend parallel to the first base member 12aa, and the second support members 13b extend parallel to the second base member 12ba.

[0084] Multiple first support members 13a and multiple second support members 13b are formed from plate-shaped components. The multiple first support members 13a and multiple second support members 13b are integrally formed.

[0085] Multiple first support members 13a and multiple second support members 13b are arranged at equal intervals. For example, the interval A1 between the multiple first support members 13a and multiple second support members 13b is 200 μm or more and 500 μm or less. Preferably, the interval A1 is 250 μm or more and 350 μm or less. This reduces the number of through holes 11 blocked by the support portion 13 and improves mechanical strength.

[0086] When the filter section 10 is viewed from the first main surface PS1 side, the width B1 of the plurality of first support members 13a and the plurality of second support members 13b is greater than the width of the plurality of first base members 12aa and the plurality of second base members 12ba of the filter base section 12. For example, the width B1 of the plurality of first support members 13a and the plurality of second support members 13b is 5 μm or more and 40 μm or less. Preferably, the width B1 is 10 μm or more and 25 μm or less. The mechanical strength of the filter 1 is obtained through the support section 13.

[0087] Figure 4 This is an enlarged view of a portion of the filter base 12, which is equipped with the support portion 13. Figure 5 yes Figure 4 An enlarged sectional view of the support portion 13 at the BB line.

[0088] like Figure 4As shown, the support portion 13 includes a main body 41 and a plurality of protrusions 43. The main body 41 has a sidewall 41a, and more specifically, a first sidewall 41aa and a second sidewall 41ab opposite to the first sidewall 41aa. The main body 41 is configured to cover part or all of the plurality of through holes 11, and the plurality of protrusions 43 are configured to protrude from the sidewall 41a of the main body 41. More specifically, the plurality of protrusions 43 protrude from the first sidewall 41aa side of the main body 41 toward the first inner wall 12a in a -Y direction, and from the second sidewall 41ab side of the main body 41 toward the second inner wall 12b in a +Y direction.

[0089] like Figure 5 As shown, the main body 41 is disposed on the first main surface PS1 and protrudes from the first main surface PS1 in the +Z direction, having a sidewall 41a along the Z direction. In this specification, "along" is not limited to a state parallel to a certain direction, but refers to a state formed near a surface parallel to that direction. The upper surface of the main body 41 may also be formed as a flat surface or a curved surface orthogonal to the Z direction.

[0090] Furthermore, the main body 41 has a plurality of fixing portions 42 disposed in a plurality of through holes 11. The fixing portions 42 extend from the first main surface PS1 toward the second main surface PS2. Figure 5 As shown, the fixing part 42 has a prism shape. The fixing part 42 can also be disposed in and embedded in the through hole 11. In this specification, "embedded" means that the volume of the object being buried is approximately the same as the volume of the contents being buried. When the embedded fixing part 42 is formed, the tightness of the support part 13 relative to the filter base part 12 is improved. On the other hand, the fixing part 42A located on the sidewall 41a side of the main body part 41 is not embedded in the through hole 11. The fixing part 42A is formed in a part of the through hole 11, and in the through hole 11 in which the fixing part 42A is disposed, the first main surface PS1 and the second main surface PS2 are partially connected. Therefore, in the through hole 11 in which the fixing part 42A is disposed, the volume formed by the through hole 11 is partially filled, forming an incomplete through hole 11.

[0091] The number of the fixed parts 42 and 42A formed can be arbitrarily set by the dimensions of the through hole 11, the filter base part 12 and the support part 13, and the extending direction of the filter base part 12 and the support part 13.

[0092] The thickness T3 of the main body portion 41 is the thickness along the Z direction from the second main surface PS2 to the protruding upper surface of the main body portion 41. The thickness T3 is, for example, 5 μm or more and 40 μm or less. Preferably, the thickness T3 of the main body portion 41 is 10 μm or more and 25 μm or less.

[0093] like Figure 5As shown, the protrusion 43 protrudes outward from the fixing portion 42A located on the sidewall 41a side of the main body portion 41 in the direction along the first main surface PS1. In Embodiment 1, the protrusion 43 is provided on each fixing portion 42A located on the first sidewall 41aa and the second sidewall 41ab side, and protrudes in the Y direction. The protrusion 43 contacts the first inner wall 12a of the fixing portion 42A located on the first sidewall 41aa side of the main body portion 41, through the hole 11. Furthermore, the protrusion 43 contacts the second inner wall 12b of the fixing portion 42A located on the second sidewall 41ab side of the main body portion 41, through the hole 11. That is, the protrusion 43 contacts the fixing portion 42A and the inner walls 12a and 12b, which are adjacent to the fixing portion 42A at intervals. The protrusion 43 may also contact the entire surface or part of each inner wall 12a and 12b. For example, the end face of the protrusion 43 is roughly aligned with the inner walls 12a and 12b, and they are in close contact with each other.

[0094] Additionally, the protrusion 43 can also seal the through hole 11 to which the fixing part 42A is disposed. In this specification, "sealing" includes completely blocking the through hole 11; however, it is not limited to the case of embedding the through hole 11, and also includes partial blocking. Therefore, the combined volume of one protrusion 43 and one fixing part 42A can be less than the volume of one through hole 11.

[0095] In embodiment 1, the protrusion 43 has a surface continuous with the first main surface PS1. In other words, the protrusion 43 does not form a step along the extension direction of the first main surface PS1, but forms a flat surface with the first main surface PS1.

[0096] The thickness T4 of the protrusion 43 is the thickness along the Z direction from the second main surface PS2 to the end of the protrusion 43 on the first main surface PS1 side. The thickness T4 is smaller than the thickness T3 of the main body 41. The thickness T4 is, for example, 0.5 μm or more and 20 μm or less. Preferably, the thickness T4 of the protrusion 43 is 1.0 μm or more and 3 μm or less.

[0097] The coefficient of thermal expansion of the material forming the filter substrate 12 is preferably approximately equal to that of the material forming the support 13. Here, "approximately equal" includes an error of up to 15%.

[0098] For example, the filter substrate 12 and the support portion 13 may also be formed of Ni or PdNi (Pd ratio: 50% to 95%). For example, the filter substrate 12 may be formed of Ni and the support portion 13 may be formed of PdNi. It should be noted that the combination of materials for the filter substrate 12 and the support portion 13 is not limited to this.

[0099] [Filter Manufacturing Method]

[0100] use Figures 6A-6G An example of the manufacturing method of filter 1 will be described. Figures 6A-6G This is a schematic diagram illustrating an example of the manufacturing process of filter 1 according to Embodiment 1 of the present invention.

[0101] like Figure 6A As shown, a Cu film 31 is formed on the substrate 30. For example, the Cu film 31 is formed by sputtering using a sputtering film deposition apparatus. Alternatively, the Cu film 31 can be formed by vapor deposition using a vapor deposition apparatus. In this case, a Ti film may also be formed between the substrate 30 and the Cu film 31 to improve the adhesion between the substrate 30 and the Cu film 31.

[0102] like Figure 6B As shown, a resist film 32 is formed by coating a Cu film 31 with a resist and allowing it to dry. For example, a photosensitive positive liquid resist is coated onto the Cu film 31 using a spin coater.

[0103] like Figure 6C As shown, the resist film 32 is exposed and developed to remove the portion of the resist film 32 corresponding to the filter substrate portion 12. Under exposure conditions, by setting the focus to a value slightly more positive than appropriate, the cross-sectional shape of the resist film 32 becomes trapezoidal.

[0104] Development was performed using a paddle-type developing apparatus. The developing solution used was TMAH (Tetramethylammonium hydroxide).

[0105] After exposure and development, the product is washed and dried.

[0106] like Figure 6D As shown, electroplating is performed using an electroplating apparatus. As a result, a plating film 33 is formed on the portion where the resist film 32 has been removed.

[0107] like Figure 6E As shown, the resist film 32 is peeled off using a stripping solution. This forms a filter substrate 12 with multiple through holes 11.

[0108] like Figure 6F As shown, a photoresist 34 is provided on the filter substrate 12. For example, a dry film photoresist with photosensitivity and a thickness of 25 μm can be used as the photoresist 34. The rigidity of the photoresist 34 prevents it from entering the through-hole 11. Alternatively, the photoresist 34 can be adhered to the filter substrate 12 using a roller lamination process.

[0109] Next, the resist 34 is exposed and developed to remove the resist 34 from the area corresponding to the support portion 13.

[0110] like Figure 6G As shown, electroplating is performed using an electroplating apparatus. As a result, a plating film 35 is formed in the portion corresponding to the support portion 13 where the resist 34 has not been formed. Since the through-hole 11 is not filled with the resist 34, the plating film 35 can flow into the through-hole 11 and contact the inner walls 12a and 12b.

[0111] After electroplating, the resist 34 was removed using an alkali (not shown). Then, the Cu film 31 was removed by etching.

[0112] In this way, filter 1 can be made.

[0113] [action]

[0114] use Figure 7 An example of the operation of filter 1 will be explained. Figure 7 This is a cross-sectional view showing a portion of the filter 1 according to Embodiment 1 of the present invention.

[0115] For filter 1, fluid including the object to be filtered flows in the direction of arrow L, i.e., from the first main surface PS1 toward the second main surface PS2. The object to be filtered is captured by the filter base 12 and held on the first main surface PS1. On the other hand, the fluid is discharged from the second main surface PS2 side through the through hole 11. A portion of the fluid may also be retained on the protrusion 43, accumulating fluid near the support 13. In addition, impurities contained in the fluid flowing over the protrusion 43 of the support 13 do not accumulate near the support 13, but move along arrow K on the protrusion 43 and the filter base 12 and pass through the through hole 11.

[0116] [Effect]

[0117] According to the filter 1 of embodiment 1, the following effects can be achieved.

[0118] The filter 1 includes: a filter base portion 12 having a first main surface PS1 and a second main surface PS2 and having a plurality of through holes 11; and a support portion 13 disposed on the filter base portion 12. The through holes 11 communicate between the first main surface PS1 and the second main surface PS2. The support portion 13 includes a main body portion 41 and a protrusion 43. The main body portion 41 is disposed on the first main surface PS1 and has a plurality of fixing portions 42, 42A disposed on the plurality of through holes 11. The protrusion 43 protrudes from the fixing portion 42A located on the side wall 41a of the main body portion 41 toward the outside of the main body portion 41 in the Y direction along the first main surface PS1. In addition, the thickness T4 of the protrusion 43 is less than the thickness T3 of the main body portion 41.

[0119] Here, a filter with an existing structure will be described. In the vicinity of the incomplete through-hole 11 in the existing filter, the flow path cross-sectional area becomes smaller, the fluid velocity increases, and thus the pressure decreases. Due to the decrease in pressure, the filterable material and the fluid are drawn towards, in particular, the incomplete through-hole 11. In Embodiment 1, "incomplete through-hole 11" refers to a through-hole 11 having an opening size smaller than size C1. Furthermore, when the filterable material is cells, the filterable material is prone to deformation. When filtering a filterable material larger than the through-hole 11, the filterable material deforms and is drawn into the incomplete through-hole 11 near the support portion 13, easily causing blockage.

[0120] On the other hand, according to the structure of the present invention, by configuring the protrusion 43 in the through hole 11 where the fixing part 42A is provided, the opening area of ​​the filter 1 formed by the incomplete through hole 11 is reduced. Therefore, in filtration using the filter 1, the amount of filtered material entering the incomplete through hole 11 and causing blockage is reduced, and blockage of the through hole 11 can be prevented. As a result, more filtered material can be recovered. In the case where the filtered material is cells, in filtration using the filter 1, the cells do not deform and block the incomplete through hole 11, therefore, more cells can be recovered.

[0121] The filter base portion 12 has inner walls 12a and 12b extending from the second main surface PS2 toward the first main surface PS1 and defining a plurality of through holes 11. The protrusion 43 contacts the first inner wall 12a and the second inner wall 12b of the through hole 11 of the fixing portion 42A located on the side wall 41a side of the main body portion 41.

[0122] With this structure, it is possible to further prevent the filterable material from entering the through hole 11 where the fixing part 42A is provided, and thus, it is possible to further suppress the clogging caused by the filterable material.

[0123] The protrusion 43 has a surface that is continuous with the first main surface PS1.

[0124] With this structure, the surface of the protrusion 43 on the first main surface PS1 side and the first main surface PS1 form a flat surface. In other words, no surface structure such as a step or other impediment to the discharge of the object is formed between the surface of the protrusion 43 and the first main surface PS1. As a result, the filtered object is not stuck on the first main surface PS1 by the surface structure and can be easily recovered. Furthermore, when using the filter 1 to filter a fluid containing impurities other than the filtered object, the impurities deposited on the protrusion 43 can move on the filter base portion 12, which is continuous with the protrusion 43, and be discharged through the through hole 11.

[0125] The protrusion 43 is sealed with a through hole 11 of a fixing part 42A located on the side wall 41a side of the main body 41.

[0126] With this structure, it is possible to further prevent the filtered material from entering the through hole 11 where the fixing part 42A is located.

[0127] Furthermore, by filling the through hole 11 with the protrusion 43, the connection between the first main surface PS1 and the second main surface PS2 can be blocked near the protrusion 43. Thus, when the filter 1 is used to filter a fluid containing the object to be filtered, the fluid that normally exits through the through hole 11 and from the second main surface PS2 side is held on the first main surface PS1 by the protrusion 43. Therefore, a liquid film is formed near the support 13, which, when the object to be filtered is cells, prevents cell drying and death, and allows for the recovery of more cells in a viable state.

[0128] Furthermore, when the filter 1 is used to filter a fluid containing the filter object, a Y-direction flow is generated near the protrusion 43, causing the filter object held on the through hole 11 and the first main surface PS1 to detach (float), thus reducing clogging. Therefore, especially when the filter object is a cell, the cell is not pressed against the through hole 11 and the first main surface PS1 for a long time, reducing the pressure exerted on the cell.

[0129] The protrusions 43 are respectively disposed on the first sidewall 41aa side and the second sidewall 41ab side of the main body 41.

[0130] With this structure, it is possible to further prevent the filtered material and fluid from entering the through hole 11 where the fixing part 42A is provided.

[0131] The support portion 13 has a plurality of first support members 13a extending along a first direction (X direction) and a plurality of second support members 13b extending along a second direction (Y direction) intersecting the first direction. The first support members 13a and the second support members 13b each have a main body portion 41 and a protrusion portion 43.

[0132] This structure can improve the strength of filter 1.

[0133] The protrusion 43 makes the size of the through-hole 11 more uniform. Therefore, when electromagnetic waves (especially visible light) are incident on the filter 1, the slit width (through-hole 11) becomes uniform during electromagnetic wave transmission. This efficiently generates electromagnetic wave interference between multiple slits, enhancing the intensity of the electromagnetic wave interference transmitted through the filter 1. Using this stronger interfering electromagnetic wave, observation of the filter 1 itself and the material captured by the filter 1 becomes easier. It should be noted that this phenomenon also occurs in the reflection towards the side where the electromagnetic wave is incident.

[0134] It should be noted that in Embodiment 1, an example was described in which the first support member 13a and the first base member 12aa extend parallel to each other, and the second support member 13b and the second base member 12ba extend parallel to each other, but this is not the only example. The first support member 13a and the first base member 12aa may also extend in different directions.

[0135] It should be noted that in Embodiment 1, an example was described where the first direction in which the first support member 13a and the first base member 12aa extend is orthogonal to the second direction in which the second support member 13b and the second base member 12ba extend, but this is not a limitation. The first and second directions can also have any relationship within the plane forming the filter base portion 12. For example, it is also possible that a plurality of first support members 13a and a plurality of first base members 12aa are formed on concentric circles relative to the circle of the filter 1, and the second support members 13b and the second base members 12ba are formed along the radial direction relative to this circle.

[0136] It should be noted that in Embodiment 1, an example was described where the size C1 of the first opening 11a and the size C2 of the second opening 11b are the same, but this is not a limitation. Alternatively, the size C2 of the second opening 11b may be larger than the size C1 of the first opening 11a. In such a structure, the support portion 13 is less likely to detach from the filter base portion 12.

[0137] It should be noted that in Embodiment 1, an example was described in which the through hole 11 of the fixing part 42A is completely filled in the protrusion 43, but this is not a limitation. For example, it is also possible that the through hole 11 protrudes in the direction (Y direction) along the first main surface PS1 compared to the fixing part 42A, and partially connects from the first main surface PS1 to the second main surface PS2. In such a structure, the opening area of ​​the through hole 11 in the first main surface PS1 can also be reduced, preventing blockage.

[0138] It should be noted that in Embodiment 1, an example was described where the protrusion 43 protrudes along the Y direction and contacts the first inner wall 12a and the second inner wall 12b of the through hole 11, but this is not a limitation. For example, the protrusion 43 may also protrude from the fixing part 42A along the X direction, contacting the third inner wall 12c and the fourth inner wall 12d. In such a structure, the opening area of ​​the through hole 11 in the first main surface PS1 can also be reduced, preventing blockage.

[0139] It should be noted that in Embodiment 1, an example with prism-shaped fixing parts 42 and 42A was described, but the embodiment is not limited to this. Fixing parts 42 and 42A may also have shapes other than pyramids to match the shape of the through hole 11. For example, if the through hole 11 has a circular shape, fixing part 42 may have a circular shape, and fixing part 42A may have a semi-circular shape. In such a structure, the support part 13 can be more firmly fixed to the filter base part 12, improving the tightness of the support part 13.

[0140] It should be noted that in Embodiment 1, an example in which the protrusion 43 forms a flat surface with the first main surface PS1 was described, but it is not limited to this. As in Modification 1 and Modification 2 described later, the protrusion 43 may protrude or be recessed relative to the first main surface PS1.

[0141] [Variation Example 1]

[0142] Figure 8A A portion of filter 1A is shown as a variation of embodiment 1. For example... Figure 8A As shown, the support portion 13 of the filter 1A includes a protrusion 43A. The protrusion 43A has a shape that protrudes from the second main surface PS2 toward the first main surface PS1 (Z direction) and out of the first main surface PS1. Furthermore, the thickness T6 of the protrusion 43A at the position where it contacts the main body portion 41 is greater than the thickness T5 of the protrusion 43A at the position where it contacts the inner wall 12b. The thicknesses T5 and T6 are the thicknesses measured along the Z direction from the second main surface PS2 to the upper surface of the protrusion 43A, and can be fixed in the support portion 13 or vary depending on the protrusion 43A. In Modification 1, the other structures of the filter 1A are the same as those of the filter 1 in Embodiment 1.

[0143] The surface of the protrusion 43A on the first main surface PS1 side can be an inclined surface extending from the sidewall 41a of the main body 41, or it can be curved and have a convex shape. Additionally, the surface of the protrusion 43A on the first main surface PS1 side can also have a recess or depression in the +Z direction relative to the first main surface PS1. The protruding shape of the protrusion 43A protrudes relative to the first main surface PS1 in the range of a few μm or a few tens of μm.

[0144] With this structure, substances such as the object to be filtered or impurities that need to be separated from the object to be filtered can be prevented from entering the through holes 11 near the support portion 13. Furthermore, it can promote the movement of impurities to other through holes 11. Impurities disposed on the convex shape move from the protrusion 43A toward the first main surface PS1 of the filter base portion 12 toward the through holes 11. In particular, the thickness T6 of the protrusion 43A is greater than the thickness T5 of the protrusion 43A, so impurities move from the position of thickness T6 toward the position of thickness T5 from the main body portion 41 toward the through holes 11. As a result, impurities can be discharged from the filter 1A. Similarly, fluid and its droplets can also be discharged from the filter 1A.

[0145] [Variation Example 2]

[0146] Figure 8B A portion of filter 1B is shown as a variation of embodiment 1. For example... Figure 8B As shown, the support portion 13 of filter 1B includes a protrusion 43B. The protrusion 43B has a shape that is recessed relative to the first main surface PS1 from the first main surface PS1 toward the second main surface PS2 (Z direction). In Modification 2, the other structures of filter 1B are the same as those of filter 1 in Embodiment 1.

[0147] The surface of the protrusion 43B on the first main surface PS1 side can be an inclined surface extending from the sidewall 41a of the main body 41, or it can be curved and have a concave shape. Additionally, the surface of the protrusion 43A on the first main surface PS1 side can also have a convex shape relative to the first main surface PS1 in the -Z direction. The concave shape of the protrusion 43B is recessed relative to the first main surface PS1 within a range of a few μm or a few tens of μm.

[0148] With this structure, liquid can be retained in the depression of the protrusion 43B, forming a pooled liquid. Cells can also be retained in the pooled liquid. As a result, drying of the filtered material, such as cells, accumulated near the support portion 13 can be prevented. In addition, cells can be collected in the depression of the protrusion 43B.

[0149] It should be noted that in Embodiment 1, an example was described in which the protrusion 43 is configured to protrude from both sides of the main body 41, but this is not a limitation. Alternatively, as in Modification 3 described later, the protrusion 43 may protrude to only one side of the main body 41.

[0150] [Variation Example 3]

[0151] Figure 9 A portion of filter 1C, a variation of embodiment 1, is shown. For example... Figure 9As shown, the support portion 13 of the filter 1C includes a main body portion 41 and a protrusion 43 protruding in the -Y direction. More specifically, the protrusion 43 is formed only between the fixing portion 42A extending from the first side wall 41aa and the first inner wall 12a. On the other hand, the second side wall 41ab of the main body portion 41 is in contact with the second inner wall 12b, and no protrusion 43 is formed between the second side wall 41ab and the second inner wall 12b.

[0152] This structure also reduces the number of incomplete through holes 11 and prevents blockage of the through holes 11. It should be noted that in Modification Example 3, an example of a protrusion 43 protruding in the -Y direction was described, but it is not limited to this. For example, the support portion 13 may also have a protrusion 43 protruding in the +Y direction from the fixing portion 42A extending from the second side wall 41ab toward the second inner wall 12b.

[0153] The invention has been fully described with reference to the accompanying drawings and preferred embodiments, but various modifications and alterations will be apparent to those skilled in the art. Such modifications and alterations are to be understood as included therein, provided they do not depart from the scope of the invention as defined by the appended claims.

[0154] Industrial availability

[0155] The filter of the present invention is able to prevent clogging, and is therefore useful in applications involving the filtration of fluids containing the object to be filtered.

[0156] Explanation of reference numerals in the attached figures

[0157] 1 filter;

[0158] 10. Filter section;

[0159] 11 through holes;

[0160] 12. Filter base section;

[0161] Inner walls of 12a, 12b, 12c, and 12d;

[0162] 12aa First base component;

[0163] 12ba second base component;

[0164] 13 Support parts;

[0165] 13a First support member;

[0166] 13b Second support member;

[0167] 20 frames;

[0168] 30 substrate;

[0169] 31Cu film;

[0170] 32. Resist film;

[0171] 33 Coating;

[0172] 34. Corrosion resist;

[0173] 35 coating;

[0174] 41. Main body section;

[0175] 41a sidewall;

[0176] 42, 42A Fixing Part;

[0177] 43. Protrusions;

[0178] PS1 First Main Page;

[0179] PS2 Second Main Page.

Claims

1. A filter comprising: a filter base portion; and a support portion provided to the filter base portion, A filter base portion having a first main surface and a second main surface on the side opposite to the first main surface, a plurality of through holes communicating the first main surface with the second main surface being formed; the support portion comprising: a main body portion provided to the first main surface, having a plurality of fixing portions provided to the plurality of through holes; and a protruding portion protruding from the fixing portions located on the side wall side of the main body portion in a direction along the first main surface toward the outside of the main body portion, the thickness of the protruding portion being smaller than the thickness of the main body portion.

2. The filter according to claim 1, wherein the filter base portion has an inner wall extending from the second main surface toward the first main surface and demarcating the plurality of through holes, the protruding portion being in contact with the inner wall of the through hole in which the fixing portion located on the side wall side of the main body portion is provided.

3. The filter according to claim 1 or 2, wherein the protruding portion has a surface continuous with the first main surface.

4. The filter according to claim 2, wherein the protruding portion has a shape protruding from the first main surface toward the first main surface from the second main surface.

5. The filter according to claim 4, wherein the thickness of the protruding portion at a position where the main body portion is in contact is greater than the thickness of the protruding portion at a position where the inner wall is in contact.

6. The filter according to claim 1 or 2, wherein the protruding portion has a shape recessed with respect to the first main surface from the first main surface toward the second main surface.

7. The filter according to claim 1 or 2, wherein the protruding portion seals the through hole in which the fixing portion located on the side wall side of the main body portion is provided.

8. The filter according to claim 1 or 2, wherein the main body portion has a first side wall and a second side wall opposite to the first side wall, the protruding portion being provided to the fixing portions located on the first side wall and the second side wall side of the main body portion, respectively.

9. The filter according to claim 1 or 2, wherein the support portion has: a plurality of first support members having the main body portion and the protruding portion, and extending in a first direction; and a plurality of second support members having the main body portion and the protruding portion, and extending in a second direction intersecting the first direction. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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