WO2016139987A1

WO2016139987A1 - Structure and collection device

Info

Publication number: WO2016139987A1
Application number: PCT/JP2016/052155
Authority: WO
Inventors: 萬壽　優; 近藤　孝志; 直樹河原; 誠治神波
Original assignee: 株式会社村田製作所
Priority date: 2015-03-04
Filing date: 2016-01-26
Publication date: 2016-09-09

Abstract

A structure is provided with: a porous body that has a plurality of through-holes; and a plurality of projections that protrude in at least one of the thickness directions of the porous body from the portion where the through-holes of the porous body are not disposed, wherein the projections have a tip section that is different from the through-holes in a planar view seen from the thickness direction of the through-holes.

Description

Structure and collection device

The present invention relates to a structure and a collection device.

A porous body having a plurality of through-holes used for filtering a solid or the like in a fluid (specimen) is known.

In Patent Document 1 (Japanese Patent Application Laid-Open No. 2012-196617), using a substrate (porous body) having a plurality of through holes, particles larger than the through holes are filtered, and particles smaller than the through holes are allowed to pass through. A sieve for classification is disclosed. And in patent document 1, in order to eliminate the problem that particles smaller than the through hole stick to each other and become a lump and cannot pass through the through hole, a plurality of particles for separating particles on the inlet side of the porous body are provided. It is disclosed that a conical or cylindrical protrusion is provided.

JP 2012-196617 A

In the porous body disclosed in Patent Literature 1, by providing a protrusion on the inlet side of the porous body, the aggregated particles are separated and the particles are prevented from fixing onto the porous body, so there is a protrusion. Compared to a porous body that does not, the particles are more easily guided to the through holes. Thereby, it is considered that an object smaller than the diameter of the through hole can easily pass through the through hole.

However, since an object that is equal to or slightly larger than the through hole is easily guided to the through hole, it is considered that the obstruction of the through hole by such an object is promoted. In particular, when the amount of an object that is equal to or slightly larger than such a through hole is increased, the risk of clogging the porous body increases. And when clogging generate | occur | produced, there existed a problem that the filtration efficiency of a porous body fell rapidly.

In view of the above circumstances, an object of the present invention is to provide a structure and a collection device that can suppress clogging and suppress a decrease in filtration efficiency.

[1] A porous body having a plurality of through holes;
A plurality of protrusions protruding from at least one of the porous body in the thickness direction from a portion where the through-hole of the porous body is not provided,
The protrusion has a structure having a tip portion that overlaps the through hole in a plan view as viewed from the thickness direction of the porous body.

[2] The structure according to [1], wherein the plurality of protrusions have a base end portion that does not overlap the through hole in a plan view as viewed from the thickness direction of the porous body.

[3] The structure according to [1] or [2], wherein the tip has an inclined portion inclined with respect to a plane perpendicular to the thickness direction of the porous body.

[4] A porous body having a plurality of through holes;
A plurality of protrusions protruding from at least one of the porous body in the thickness direction from a portion where the through-hole of the porous body is not provided,
At least one of the plurality of protrusions is a structure in which a length in the thickness direction of the porous body is different from at least one other protrusion of the plurality of protrusions.

[5] The structure according to [4], wherein the protrusion has a tip portion that overlaps the through hole in a plan view as viewed from the thickness direction of the porous body.

[6] The structure according to any one of [1] to [5], wherein the tip has an inclined portion inclined with respect to a plane perpendicular to the thickness direction of the porous body.

[7] A collection device used for collecting an object in a fluid,
The structure according to any one of [1] to [6];
Provided on the upstream side of the structure in the flow path of the fluid, contaminants larger than the object cannot pass, the object, contaminants smaller than the object, and before the fluid can pass And a processing filter.

According to the present invention, it is possible to provide a structure and a collecting device that can suppress clogging and suppress a decrease in filtration efficiency.

1 is a schematic diagram illustrating a configuration of a structure according to Embodiment 1. FIG. (A) is a perspective view, (b) is a side view, and (c) is a top view. FIG. 6 is a schematic diagram illustrating a modification of the structure according to the first embodiment. (A) is a top view, (b) is a side view. FIG. 6 is a schematic diagram illustrating a configuration of a modified example of the structure according to the first embodiment. (A) is a top view, (b) is a side view. FIG. 3 is a schematic cross-sectional view for explaining a configuration of a protrusion of the structure body according to the first embodiment. FIG. 5 is a schematic diagram illustrating a configuration of a structure according to a second embodiment. (A) is a perspective view, (b) is a side view, and (c) is a top view. 10 is a schematic diagram illustrating a configuration of a structure according to Embodiment 3. FIG. (A) is a side view, (b) is a top view. It is a schematic diagram for comparing the effect of the structure of Embodiment 3. (A) is a side view, (b) is a top view. FIG. 3 is a schematic cross-sectional view for explaining the size of each part of the protrusion according to the first embodiment. It is a cross-sectional schematic diagram for demonstrating an example of the manufacturing method of the structure of Embodiment 4. It is a cross-sectional schematic diagram which shows the structure of the collection apparatus of Embodiment 5. It is the schematic which shows an example of a structure of a membranous porous body. (A) is a perspective view, (b) is a plan view.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same reference numerals represent the same or corresponding parts. In addition, dimensional relationships such as length, width, thickness, and depth are changed as appropriate for clarity and simplification of the drawings, and do not represent actual dimensional relationships.

In addition, each embodiment is an illustration, and it cannot be overemphasized that the partial substitution or combination of the structure shown in different embodiment is possible. In the second and subsequent embodiments, description of matters common to the first embodiment is omitted, and only different points will be described. In particular, the same operation effect by the same configuration will not be sequentially described for each embodiment.

[Embodiment 1]
FIG. 1 is a schematic diagram illustrating a configuration of a structure according to the first embodiment. With reference to FIG. 1, the structure 1 of the present embodiment includes a membrane-like porous body 10 having a plurality of through holes 11 and a plurality of protrusions 12.

The plurality of protrusions 12 protrude from the portion of the membranous porous body 10 where the through holes 11 are not provided to one side in the thickness direction of the membranous porous body 10. That is, the protrusion 12 is provided on one main surface of the membranous porous body 10.

(Porous material)
Referring to FIG. 11, a porous body (film-like porous body) 10 in the present embodiment has a first main surface 10a and a second main surface 10b facing the first main surface 10a. The through hole 11 penetrates from the first main surface 10a toward the second main surface 10b. That is, the through hole 11 penetrates in the thickness direction of the membranous porous body 10.

In the membranous porous body of the present embodiment, it is preferable that the plurality of through holes 11 are periodically arranged in at least one direction on the main surface of the membranous porous body 10. Thereby, a structure with stable filtration characteristics can be obtained. However, all of the through-holes 11 may be periodically arranged, and some through-holes 11 are periodically arranged and other through-holes 11 are non-existing as long as the filtration characteristics do not become unstable. You may arrange | position periodically.

The membranous porous body 10 may have an outer peripheral portion (not shown) around the plurality of through holes 11. In addition, an outer peripheral part turns into a part pinched by the fixing member in order to fix the structure 1 in the case of filtration, for example.

The plurality of through-holes 11 of the membranous porous body 10 are not particularly limited as long as the target object having a predetermined size can be collected. For example, the target object cannot physically pass or is difficult to pass. The size is preferred. Moreover, it is preferable that it is a magnitude | size which a fluid can pass easily.

“The size in which the object cannot physically pass or is difficult to pass” means, for example, that the hole size of the through-hole 11 indicated by D in FIG. The size of the through hole 11 is equal to or less than the length of the longest straight line connecting the two upper points. In addition, when the target object can be partially deformed (for example, nucleated cells), “the size that the target object cannot physically pass or is difficult to pass” means that the pore size is deformable. It means the size of the through-hole 11 that is equal to or less than the major axis of the missing part. When the entire object is deformed, the “size that the object cannot physically pass or is difficult to pass” is preferably a through-hole 11 such that the hole size is 1/20 or less of the major axis of the object. Is the size of

For example, when the membranous porous body 10 is the membranous porous body 10 in which the through-holes 11 are regularly arranged vertically and horizontally as shown in FIG. 11, the through-hole 11 shown by D in FIG. The hole size is preferably, for example, not more than the length of the longest line connecting the two points on the surface of the object.

Specifically, the size of the through hole 11 is preferably 0.05 μm or more and 100 μm or less. For example, when it is desired to collect particles of submicron order with the structure 1, the size of the through hole 11 is preferably 0.5 μm or less.

The shape of the through hole 11 is not particularly limited. The shape of the through hole 11 viewed from the thickness direction of the porous body (membrane-like porous body 10) is not limited to a square as shown in FIG. 11B, but may be a rectangle, a circle, an ellipse, or the like.

The ratio (opening ratio) of the opening area of the through hole 11 to the area of the main surface of the membranous porous body 10 including the through hole 11 is 3% or more from the viewpoint of increasing the flow rate of the fluid passing through the structure 1. Preferably, it is 10% or more. Further, from the viewpoint of ensuring the strength of the structure 1 (membrane porous body 10), it is preferably 80% or less, and more preferably 60% or less. The aperture ratio can be adjusted, for example, by designing the hole size of the through hole 11 indicated by D in FIG. 11B and the lattice spacing (pitch) of the through hole 11 indicated by P.

The average thickness of the membranous porous body 10 is preferably as thin as possible within a range where necessary mechanical strength can be maintained. When the average thickness of the membranous porous body 10 is increased, generally the pressure loss when the fluid is passed increases. This is because when the pressure loss of the structure 1 becomes large, the flow rate becomes slow and it becomes difficult to flow the fluid, so that there is a problem that the processing efficiency is lowered.

In addition, by reducing the average thickness of the membranous porous body 10, the thickness of the structure 1 can also be reduced. For example, a method for measuring an object by irradiating the structure 1 in which the object is collected with an electromagnetic wave. When used for the measurement, the measurement sensitivity is improved, and it becomes possible to measure a smaller amount of the object to be measured. Here, the thickness of the membranous porous body 10 is an average value (average thickness) of the distance between the first main surface 10a and the second main surface 10b. The average thickness of the membranous porous body 10 can be calculated as an average value of all measured values by measuring 10 locations per porous body with fluorescent X-rays.

Specifically, the average thickness of the membranous porous body 10 is preferably 0.2 μm or more and 40 μm or less, and more preferably 0.5 μm or more and 5 μm or less.

(Projection)
As shown in FIG. 1C, the structure 1 of the present embodiment has a tip in which a part of the plurality of protrusions 12 overlaps the through-hole 11 in a plan view as viewed from the thickness direction of the membranous porous body 10. It has the part 12b.

Since the distance between the plurality of projections 12 is narrower than the through-holes 11 of the structure 1 by the tip 12b, an object having a size that closes the through-holes 11 of the structure 1 So that it does not reach the through hole 11. In addition, since all the side parts of the protrusion 12 are openings, even when the object is held on the upper part of the protrusion 12, a flow path can be secured on the side part. Therefore, clogging of the structure 1 due to the object can be suppressed, and a decrease in the filtration efficiency of the structure 1 can be suppressed. Such a clogging suppressing effect is particularly effective when the amount of the target object to be filtered is large and a large amount of the target object is deposited on the tip of the protrusion 12.

In the present specification, the “plan view as viewed from the thickness direction of the membranous porous body 10” may be simply referred to as “plan view”. In the present embodiment, the thickness direction of the membranous porous body 10 corresponds to the normal direction of the first main surface 10a (or the second main surface 10b).

The shape of the protrusion 12 may be such that a part of the plurality of protrusions 12 overlaps with the through hole 11 in plan view, and the base that does not overlap with the through hole 11 in plan view as shown in FIGS. 1 and 2. The shape is not limited to the end portion 12a and the tip portion 12b overlapping the through hole 11. That is, in the cross-sectional shape in a plane parallel to the thickness direction of the membranous porous body 10, for example, as shown in FIG. The shape may be a tip-expanding shape having a tapered diameter from the proximal end side toward the distal end side.

In addition, in a plan view as viewed from the thickness direction of the membranous porous body 10, the total number of through holes 11 of the membranous porous body 10 is 50% or more (more preferably 80% or more, more preferably substantially 100% of the through-holes 11 preferably overlap with the tip 12b of the protrusion 12. In this case, clogging can be more reliably suppressed.

Each of the through holes 11 overlapping the tip 12b of the protrusion 12 overlaps the tip 12b of at least one protrusion 12 in a plan view as viewed from the thickness direction of the membranous porous body 10, preferably At least two protrusions 12 overlap the tip portions 12b. In FIG. 1C and FIG. 2A, each of the through holes 11 that overlap the tip portion 12 b of the protrusion 12 overlaps the tip portions 12 b of the four protrusions 12.

Further, the position where the protrusion 12 is provided is not particularly limited. In FIGS. 1 and 2, the protrusion is provided on the intersection of the crosspieces of the membranous porous body 10, but may be provided at a position other than the intersection. Further, in FIGS. 1 and 2, the protrusions 12 are provided on all the intersections of the crosspieces of the membranous porous body 10, but it is not necessary to provide them on all the intersections, for example, on every other intersection. You may make it provide in.

However, as shown in FIGS. 1 and 2, the shape of the protrusion 12 is a shape including a base end portion 12 a that does not overlap the through hole 11 and a tip end portion 12 b that overlaps the through hole 11 in plan view. Is preferred. In this case, the volume of the space (gap) around the base end portion 12a is larger than the projection 12 having a shape as shown in FIG. 4, and the flow path in the vicinity of the through hole 11 is secured more widely. The effect of suppressing clogging can be enhanced.

In addition, the shape in plan view of each of the base end portion 12a and the tip end portion 12b of the protrusion 12 is not particularly limited, and may be various shapes such as a circle and a rectangle, but is preferably a circle. When the target is susceptible to damage such as red blood cells, damage due to the protrusions 12 can be suppressed. Further, by chamfering the periphery of the tip, damage to the object can be further suppressed.

Referring to FIG. 8 and FIG. 1B, the specific sizes of the respective parts of the membranous porous body 10 and the protrusions 12 are illustrated as follows.

For example, when the size of the object is 8 μm or more and 14 μm or less, the hole size D of the through hole 11 of the membranous porous body 10 is, for example, 2 μm or more and 7 μm or less. Further, the width A (pitch P−hole size D) of the crosspieces of the membranous porous body 10 is, for example, not less than 0.5 μm and not more than 100 μm.

The length L of the base end portion 12a of the protrusion 12 (the length in the thickness direction of the membranous porous body 10) is, for example, not less than 0.5 μm and not more than 100 μm. The ratio of L to A is, for example, 10% or more and 500% or less.

The ratio of the diameter B of the base end portion 12a of the protrusion 12 (the width in the direction perpendicular to the thickness direction in the cross section parallel to the thickness direction) to A is, for example, 10% or more and 100% or less. Further, the height H of the entire protrusion 12 (the length in the thickness direction of the membranous porous body 10) is, for example, 1 μm or more and 300% or less of L.

The structure 1 (the membrane-like porous body 10 and the protrusion 12) is preferably formed at least partially including a conductor, and more preferably the entire structure 1 is formed of a conductor. Here, the conductor is an object (material) that conducts electricity, and includes not only metals but also semiconductors.

Examples of the metal include nickel, gold, silver, copper, platinum, iron, chromium, titanium, cobalt, and alloys thereof. Nickel, gold, silver, copper, platinum, chromium and titanium are preferable, and nickel and gold are more preferable.

The structure 1 of the present embodiment can be used as a filter (sieving) for filtering an object contained in a fluid (specimen). In addition, when filtering, it is preferable that the membranous porous body 10 is installed in the fluid flow path so that the main surface side on which the protrusions 12 are provided is the upstream side of the fluid flow.

The fluid is, for example, a gas or a liquid. Examples of the target substance include inorganic substances, organic substances or composites thereof contained in a fluid, biological substances (for example, blood cells such as erythrocytes) or microorganisms. In addition, the target object should just have a shape in the state which exists in the fluid, and may be not only solid but sol, gel, etc.

Examples of the inorganic substance, the organic substance, or a composite thereof in the gas include atmospheric PM (Particulate Matter) 2.5, SPM (Suspended Particulate Matter), PM10, and pollen. PM2.5 is a particulate substance floating in the atmosphere, and has a particle diameter of approximately 2.5 μm or less.

The “biological substance” has a meaning including a living substance such as a cell or a microorganism and a substance derived from a living thing such as a virus.

Examples of cells include eukaryotic cells. As eukaryotic cells, for example, eggs, sperm, induced pluripotent stem cells (iPS cells), ES cells, stem cells, mesenchymal stem cells, mononuclear cells, single cells, cell clusters, suspension cells, adhesive cells, Examples thereof include nerve cells, leukocytes, lymphocytes, cells for regenerative medicine, autologous cells, cancer cells, circulating cancer cells (CTC), HL-60, and HeLa cells. Contains fungi.

Examples of microorganisms include eukaryotes such as fungi, and prokaryotes such as bacteria. Examples of bacteria (eubacteria) include gram positive bacteria, gram negative bacteria, Escherichia coli, and tuberculosis bacteria.

Examples of the virus include DNA virus, RNA virus, rotavirus, (bird) influenza virus, yellow fever virus, dengue fever virus, encephalitis virus, hemorrhagic fever virus, immunodeficiency virus, and the like.

In Embodiment 1, the structure 1 can be suitably used particularly for collecting induced pluripotent stem cells (iPS cells), ES cells, stem cells, and circulating cancer cells (CTC) in the blood.

In addition to the above-described target object, for example, the structure 1 of the present embodiment can be applied to the collection of the following target object.

As a new test method for cancer, research is being conducted to quantify exosomes (endoplasmic reticulum) derived from cancer cells in blood. The size of the exosome is about several hundred nm, and the structure 1 of the above embodiment is applied to collect (filter and concentrate) only the exosome from a blood sample from which leukocytes, erythrocytes and other blood cells have been removed. be able to.

In addition, since norovirus cannot be cultured, a considerable amount of time has passed since the onset of the disease, and there is a problem that inspection cannot be performed unless the number of viruses increases. Rapid inspection is possible without culture. For this reason, the structure 1 of the said embodiment can also be applied to the selective collection of such a virus.

As shown in FIG. 3, a protrusion 14 having a height different from that of the protrusion 12 may be provided between the plurality of protrusions 12. For example, when a deformable object such as a cell is filtered, the object may be deformed toward the through-hole 11 and approach the through-hole 11 even if the object is held at the top of the protrusion 12. At this time, by arranging the protrusion 14 having a height different from that of the protrusion 12, the object can be prevented from approaching the through hole 11. Therefore, by providing the projection 14 having a height different from that of the projection 12, it is possible to more reliably prevent the object from blocking the through hole 11.

In addition, in FIG.3 (b), the height of the

protrusions

12 and 14 whole is changed by changing the height of the front-end | tip

parts

12b and 14b of the

protrusions

12 and 14. FIG. However, the height of the

protrusions

12 and 14 may be changed by changing the height of the

base end portions

12a and 14a. Even in this case, the same effect as described above can be obtained.

[Embodiment 2]
With reference to FIG. 5, the structure 1 of the present embodiment is different from that of the first embodiment in that the tip of the protrusion 12 has a rounded shape. Since the other points are the same as those of the first embodiment, a duplicate description is omitted.

As in the present embodiment, the tip of the protrusion 12 has an inclined portion that is inclined with respect to a plane perpendicular to the thickness direction of the membranous porous body 10, so that the target object is softly broken like a cell. It is easy to be done, and when it is desired to filter without destroying such an object, it is possible to prevent the object from being damaged at the tip 12b of the protrusion 12. Note that, as shown in FIG. 5, not only when the entire tip of the protrusion 12 has a rounded shape, but a part of the tip of the protrusion 12 is a plane perpendicular to the thickness direction of the membranous porous body 10. If it has an inclined part inclined with respect to (for example, if the tip part is basically rectangular but the corner part is chamfered), the same effect can be obtained. Can do. The inclination is preferably such that the height of the tip of the protrusion 12 decreases from the center of the protrusion 12 to the outer peripheral end.

[Embodiment 3]
Referring to FIG. 6, in the structure according to the present embodiment, at least one of the plurality of protrusions 12 (projection 13) is at least one other protrusion of the plurality of protrusions 12, and a membrane-like porous body. 10 differs from

Embodiments

1 and 2 in that the length in the thickness direction is different. Since the other points are the same as those in the first and second embodiments, the overlapping description is omitted.

As shown in FIG. 6, when the heights of some of the plurality of protrusions 13 are different from those of the other protrusions 12, the heights of the plurality of protrusions 12 are all the same as shown in FIG. 7. Even when the amount of red blood cells 9 (target object) held at the tips of the

protrusions

12 and 13 is larger than in some cases, the plurality of red blood cells 9 are held in different directions, so Air gaps are easily secured and clogging is less likely to occur.

Here, the case where some of the protrusions 13 are higher than the other plurality of protrusions 12 has been described, but conversely, even if some of the protrusions are lower than the other plurality of protrusions, The same effect is produced.

In the present embodiment, it is not always necessary that some of the plurality of protrusions 12 overlap the through-holes 11 in a plan view as viewed from the thickness direction of the membranous porous body 10. Even in the case where a part of the plurality of protrusions 12 does not overlap with the through hole 11 in a plan view, the effect of the above-described embodiment can be obtained if the heights of the plurality of protrusions 12 are different.

[Embodiment 4]
This embodiment is an embodiment of a method for manufacturing a structure. The structures 1 according to the first to third embodiments are, for example, known various lithography methods using a mask (resist) that is patterned so that the desired through-holes 11 and protrusions 12 are formed as described above. Etc. can be manufactured.

The structure manufacturing method of the present embodiment mainly includes a step of forming the membranous porous body 10, a protrusion 12 formed on the membranous porous body 10, and the membranous porous body 10 and the protrusion 12 are combined. And obtaining a structure 1 comprising: Hereinafter, with reference to FIG. 9, an example of the manufacturing method of the structure of this embodiment will be described.

First, referring to FIG. 9A, a substrate 2 is prepared. Although the board | substrate 2 is not specifically limited, For example, it consists of Si.

Next, referring to FIG. 9B, a Ti film and a Cu film are formed in this order on the substrate 2 by sputtering to form a laminated film (metal film 3) composed of the Ti film and the Cu film. . The metal film 3 is a layer that is removed by etching in a later step, but also functions as a seed layer for Ni plating when the film-like porous body 10 is formed. In addition, as another effect, for example, there is an effect that the surface roughness of the Cu film can be adjusted and the adjusted surface state can be transferred to the Ni surface.

The thickness of the metal film 3 is not particularly limited, but is preferably as thin as possible within the range in which the structure 1 of the present embodiment can be obtained because it is partially removed in a later step. Specifically, for example, the thickness of the metal film 3 is preferably 100 to 600 nm. For example, the thickness of the Ti film may be about 20 nm, and the thickness of the Cu film may be about 200 nm to 500 nm.

Next, referring to FIG. 9C, a first resist 41 is formed on the metal film 3. Next, the first resist 41 is patterned by a photolithography method so as to have an opening at a position corresponding to a portion where the membranous porous body 10 is formed, as shown in FIG. 9D. .

Next, referring to FIG. 9E, a film-like porous body 10 (Ni film) is formed on the surface of the metal film 3 exposed in the opening of the first resist 41 by a plating method (electrolytic plating method). . Thus, the membranous porous body 10 having a plurality of through holes 11 penetrating in the normal direction of the main surface (the thickness direction of the membranous porous body 10) is formed.

Next, referring to FIG. 9 (f), a second resist 42 is formed on the membranous porous body 10. Next, as shown in FIG. 9G, the second resist 42 is patterned so as to have an opening at a position corresponding to a portion where the protrusion 12 is formed.

Next, referring to FIG. 9H, a protrusion 12 (Ni film) is formed on the surface of the film-like porous body 10 exposed at the opening of the second resist 42 by a plating method. Accordingly, as shown in FIG. 9 (h), the protrusion 12 is formed on one main surface of the membrane-like porous body 10 (the portion where the through hole 11 is not provided) in the thickness direction of the membrane-like porous body 10. It is formed so as to include a plurality of protrusions 12 protruding in the (normal direction of the first main surface).

At this time, by adjusting the plating amount (plating time) so as to overflow from the opening of the second resist 42, the overflowed plating forms the front end portion 12 b of the protrusion 12. Note that the plating formed in the opening of the second resist 42 becomes the base end portion 12 a of the protrusion 12.

In this case, the shape of the tip 12b of the projection 12 is usually rounded due to surface tension or the like. That is, the tip of the protrusion 12 has an inclined portion that is inclined with respect to a plane perpendicular to the thickness direction of the membranous porous body 10.

In the case of obtaining the structure 1 of the third embodiment, for example, the opening of the second resist 42 corresponding to the portion serving as the base end portion 13a of the protrusion 13 of the plurality of protrusions 12 is made more than others. Also design thinly. Thereby, since the total amount of the plurality of

projections

12 and 13 formed by plating is basically the same, the tip end portion 13b of the projection 13 is larger than the tip end portion 12b of the projection 12. The height of the protrusion 13 can be made higher than that of the other plurality of protrusions 12 by the height of the tip end portion 13 b of the protrusion 13.

Next, referring to FIG. 9I, the second resist 42 is removed by a peeling method.
Next, referring to FIG. 9J, the metal film 3 is removed by etching. Examples of the etching method include a method of immersing the precursor of the structure 1 obtained in the above step in an etching solution for dissolving a metal film. Note that the etching solution is washed by, for example, rinsing with pure water, and then dried.

Through the above steps, the structure 1 of the present embodiment composed of the membranous porous body 10 and the protrusions 12 (13) can be obtained.

In this embodiment, the membranous porous body 10 and the protrusions 12 are formed using a resist, but the membranous porous body 10 and the protrusions 12 may be formed by other methods. For example, by using a plating bath to which a leveling agent or a brightening agent is added, the membranous porous body 10 and the protrusions 12 may be formed while simultaneously controlling the surface roughness and the shape of the protrusions. Alternatively, the membranous porous body 10 and the protrusions 12 may be formed by vapor deposition of metal, resin, or the like. Moreover, when the membranous porous body 10 and the protrusions 12 are made of resin, the membranous porous body 10 and the protrusions 12 may be formed by patterning a photocurable resin.

In addition, the combination of the material of the membranous porous body 10 and the protrusion 12 is not particularly limited, but from the viewpoint of improving the binding properties of the both, and from the viewpoint of obtaining uniform characteristics as a whole structure when used for electromagnetic wave measurement. The combination of the same kind of materials is preferable.

[Embodiment 5]
The present embodiment is an embodiment of a collection device using the structures of the first to third embodiments. In addition, the collection apparatus of this embodiment is a collection apparatus used in order to collect the target object by filtering the target object in the fluid. Hereinafter, the collection measure of the present embodiment will be described with reference to FIG.

As shown in FIG. 10, the pretreatment filter 1 </ b> A and the structure 1 are arranged in series in the flow path formed by the cylinder 5. That is, the pretreatment filter 1A is provided on the upstream side of the structure 1 in the fluid flow path.

The pretreatment filter 1A is a filter through which a foreign substance larger than the target object cannot pass and a target object, a foreign substance smaller than the target object, and a fluid can pass.

In the collection apparatus of the present embodiment, as the structure 1, for example, the structure of any of the first to third embodiments is used. Thereby, the collection apparatus which can suppress clogging and can suppress the fall of filtration efficiency can be provided.

As the pretreatment filter 1A, for example, a membrane filter or the structures of the first to third embodiments can be used. Further, a plurality of these preprocessing filters may be arranged in series.

When the structures of the first to third embodiments are used as the pretreatment filter 1A, the size of the through hole 11 (for example, the hole size of the through hole 11 indicated by D in FIG. 11B) is larger than the target product. It is preferable that the foreign substance cannot pass through or is difficult to pass through, and the target article can pass through. Thereby, in the pre-processing filter 1A, the target object can be passed without being removed, and only impurities larger than the target object can be collected (removed). Therefore, clogging of the structure 1 due to contaminants can be suppressed, and a decrease in filtration efficiency can be further suppressed.

For example, when the membranous porous body 10 is a membranous porous body in which the through-holes 11 are regularly arranged in the vertical and horizontal directions as shown in FIG. 11A, the through-hole shown by D in FIG. The size of the hole 11 is larger than the size of the target object (for example, the length of the longest straight line connecting two points on the surface of the target object), and is larger than the target object (for example, the foreign object). It is preferable that the length of the longest straight line connecting two points on the surface is less than or equal to.

Then, by flowing a fluid (specimen) so as to pass through the pretreatment filter 1A and the structure 1 in this order, contaminants larger than the target object are removed by the pretreatment filter 1A. The object can be collected.

By using the structures of Embodiments 1 to 3 that can suppress clogging as the pretreatment filter 1A, clogging due to contaminants in the pretreatment filter 1A can be suppressed. Further, by using the structure according to the first to third embodiments having a larger flow rate ratio than the membrane filter or the like as the pretreatment filter 1A, the pressure loss of the entire collection device can be reduced and the filtration efficiency can be improved. .

(Example 1)
A membranous porous body 10 having a diameter of 6 mm was produced at the center of a structure made of a circular nickel film having a diameter of 7.8 mm. For the membranous porous body 10, referring to FIG. 8, the hole size D of the through hole 11 of the membranous porous body 10 is 4.5 μm, the width A of the crosspiece is 2.0 μm, and the length L of the base end portion 12 a is The diameter B of the base end portion 12a was 1 μm, and the height H of the entire protrusion 12 was 5.5 μm. Moreover, the film thickness of the membranous porous body 10 was 1.5 μm.

To this structure, a suspension containing 1 × 10 ⁴ cells HL60 having a substantially spherical shape and a size of 12 μm was added. The liquid volume was 10 mL. As a result of filtration by the dead end method, the entire amount of cells and liquid could be separated in 265 seconds.

(Comparative Example 1)
Although it was the same as in Example 1, a membranous porous body without protrusions was prepared, and the cell suspension similar to that in Example 1 was filtered by the dead end method. As a result, even after 10 minutes, the cells and the liquid could not be separated completely. At the time when 6 minutes had passed, the through-holes of the membranous porous body were blocked by cells, so that the liquid did not pass through the membranous porous body.

(Result 1)
In Example 1 which concerns on this invention, compared with Comparative Example 1, clogging was suppressed and the filtration efficiency was able to be improved.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 structure, 1A pretreatment filter, 10 membrane porous body, 10a first main surface, 10b second main surface, 11 through-hole, 12, 13, 14 protrusion, 12a, 13a, 14a base end, 12b, 13b , 14b tip, 2 substrate, 3 metal film, 41 1st resist, 42 2nd resist, 5 cylinder, 9 red blood cells.

Claims

A porous body having a plurality of through holes;
A plurality of protrusions protruding from at least one of the porous body in the thickness direction from a portion where the through-hole of the porous body is not provided,
The protrusion has a structure having a tip portion that overlaps the through hole in a plan view as viewed from the thickness direction of the porous body.
The structure according to claim 1, wherein the plurality of protrusions have a base end portion that does not overlap the through hole in a plan view as viewed from the thickness direction of the porous body.
The structure according to claim 1 or 2, wherein the tip has an inclined portion inclined with respect to a plane perpendicular to the thickness direction of the porous body.
A porous body having a plurality of through holes;
A plurality of protrusions protruding from at least one of the porous body in the thickness direction from a portion where the through-hole of the porous body is not provided,
At least one of the plurality of protrusions is a structure in which a length in the thickness direction of the porous body is different from at least one other protrusion of the plurality of protrusions.
The structure according to claim 4, wherein the protrusion has a tip portion overlapping the through hole in a plan view as viewed from the thickness direction of the porous body.
The structure according to claim 5, wherein the tip has an inclined portion inclined with respect to a plane perpendicular to the thickness direction of the porous body.
A collection device used to collect a target object in a fluid,
A structure according to any one of claims 1 to 6;
Provided on the upstream side of the structure in the flow path of the fluid, contaminants larger than the object cannot pass, the object, contaminants smaller than the object, and before the fluid can pass And a processing filter.