JP7566307B2 - Structure - Google Patents

Description

The present invention relates to a structure. More specifically, the present invention relates to a structure that is widely used in various fields such as medicine, biochemistry, pharmacology, chemistry, food, the environment, and engineering.

In recent years, the development of technologies that make effective use of small amounts of liquid has been progressing in various fields. For example, in the medical field, it has become possible to simply diagnose illnesses by qualitatively identifying target components in bodily fluids such as blood and urine (Patent Documents 1 to 5).

Patent Document 1 discloses a simple analytical chip having a multi-layer structure processed by photolithography. The tip of the flow channel of this chip is provided with a detection section equipped with various color-developing materials, and it is described that if an analytical component is present in a sample, the degree of color development in the detection section can be visually determined, and the amount of the target component in the sample can be determined based on the amount of change in reflected light.
Patent Documents 2 to 4 also disclose similar simple analysis chips and test papers, and describe how the color change (colorimetric method) according to the amount of the target component present, i.e., the amount of change in reflected light (scattered light) from the substrate surface, is quantified visually or through image processing.

JP 2012-230125 A Special table 2014-529083 publication JP 2013-53869 A JP 2009-115822 A JP 2013-148592 A

However, the technologies in Patent Documents 1 to 5 are technologies specialized for the medical field, and are not technologies that can be used in other fields (e.g., engineering, the environment, food, etc.). These documents do not anticipate using them for other purposes, and there is no description or suggestion of such use.

In view of the above circumstances, the present invention aims to provide a structure that allows a small amount of sample to be used in a variety of fields.

The structure of the present invention has a main body having through holes penetrating the front and back of a substrate, the main body having a plurality of voids inside the substrate that communicate with the through holes and through which liquid can pass by capillary action, and the through holes are formed to a size that can hold liquid by surface tension.

According to the structure of the present invention, when a liquid sample (hereinafter simply referred to as liquid) is supplied to the liquid supply section of the main body, the supplied liquid passes through the inside of the substrate and forms a liquid film (also referred to as liquid phase) in the through-hole, and this liquid film can be used for the desired purpose.

FIG. 1 is a schematic explanatory diagram of a structure 1 according to an embodiment of the present invention. 2 is a schematic enlarged cross-sectional view of the main body 10 taken along line IIA-IIA in FIG. 1, with (X) and (Y) being schematic explanatory views in which the base material 10a is made of another material. 1A and 1B are a schematic plan view and a schematic cross-sectional view of a structure 1 according to an embodiment of the present invention. FIG. 1 is a schematic explanatory diagram illustrating a structure 1 of the present embodiment used as a chip for spectroscopic analysis. 11 is a schematic explanatory diagram of a change in the liquid surface shape of a liquid film Lf formed in a through hole 11h of the structure 1 of this embodiment. FIG. FIG. 1 is a schematic explanatory diagram of a structure 1 of the present embodiment in which a through hole 11h has an elliptical shape. FIG. 1 is a schematic explanatory diagram of a structure 1 according to an embodiment of the present invention. FIG. 1 is a schematic explanatory diagram of a structure 1 according to an embodiment of the present invention. FIG. 1 is a schematic explanatory diagram showing the structure 1 of the present embodiment used as a filtering device. FIG. 1 is a schematic explanatory diagram of a structure 1 according to an embodiment of the present invention. FIG. 1 is a schematic explanatory diagram showing the structure 1 of this embodiment used as a liquid sprayer. FIG. 1 is a schematic explanatory diagram of a structure 1 used in Experiment 1. FIG. 13 shows experimental results. FIG. 13 shows experimental results. FIG. 13 shows experimental results. FIG. 13 shows experimental results. FIG. 13 shows experimental results. FIG. 13 shows experimental results. FIG. 13 shows experimental results.

Next, the present embodiment of the present invention will be described with reference to the drawings.
The structure of this embodiment is characterized in that it enables a small amount of liquid to be used in various fields.

In the specification, the liquid is not particularly limited as long as it is liquid and has fluidity when the structure of this embodiment is supplied. For example, various solvents (single or mixed) such as water, alcohol, organic solvents, and industrially used solvents can be used as the solvent for the liquid. In addition, the liquid may be in any state, whether the contained components are dissolved, dispersed, or partially precipitated. For example, samples can be body fluids such as blood and urine, environmental water such as rivers, industrial wastewater discharged from factories, various medical drugs for humans and animals (including liquids, powders, and solids dissolved or dispersed in water or solvents), foods, industrial products, etc., but needless to say, they are not limited to these.

Before going into detail about the features of the structure of this embodiment, we will first provide an overview of the structure.

(Outline of Structure 1)
The structure 1 includes a main body 10 having a substrate 10a through which liquid can pass, and the main body 10 includes a through-hole region 11 and a liquid supply section 12. A plurality of voids 10h through which liquid can pass by capillary action are formed inside the substrate 10a of the main body 10. The through-hole region 11 of the main body 10 has a through-hole 11h penetrating the front and back of the substrate 10a. The openings of the plurality of voids 10h are formed on the inner wall of the through-hole 11h. That is, the voids 10h formed inside the substrate 10a are formed so as to communicate with the through-hole 11h, and the openings of the voids 10h are formed so as to be located on the inner wall surface of the through-hole 11h. Furthermore, the through-hole 10 is formed to a size that can hold the liquid by surface tension.

Because of the above configuration, if the desired liquid L is supplied to the liquid supply section 12 of the structure 1, the voids 10h in the substrate 10a can be moved to the through-hole region 11 by capillary action. In the substrate 10a, a void network consisting of fine voids 10h through which the liquid L can pass by capillary action is formed, so that the liquid L moves to the through-hole 11h while moving through this void network, and impurities (contaminant components) in the liquid L are separated and removed. In other words, the main body 10 can move the liquid L from the liquid supply section 12 to the through-hole region 11 by the filter function of the substrate 10a. Specifically, the multiple components present in the liquid L are appropriately sieved according to their size by the filter function of the substrate 10a. For example, when the target component and impurities are present in the supplied liquid L, the components in the liquid L can be moved to the through-hole region 11 while being separated and removed into the target component and the impurities.

The liquid L that has reached the through-hole region 11 flows into the through-hole 11h from the opening of the gap 10h formed on the inner wall surface of the through-hole 11h. At this time, the liquid L that has reached the opening of the gap 10h through the gap 10h first spreads along the inner wall of the through-hole 11h on the inner wall surface of the through-hole 11h due to surface tension. Then, the liquid L that has covered the inner wall surface of the through-hole 11h spreads toward the center of the through-hole 11h. The film of the liquid L that spreads toward the center of the through-hole 11h spreads while trapping the layer of air toward the center of the through-hole 11h so as to make the cross section circular. Then, when this layer of air finally repels, the liquid L that has spread toward the center is connected, and a film of the liquid L (macroscopically it is a liquid film Lf, and microscopically it can also be said to be a liquid phase Lf, but hereinafter it is simply called a liquid film Lf) is formed in the through-hole 11h. This liquid film Lf is held in the through-hole 11h by surface tension, so it can be maintained in the through-hole 11h without providing a retaining layer or the like at the front opening 11ha and the back opening 11hb of the through-hole 11h. The liquid film Lf formed in the through-hole 11h as described above can be used for various purposes. Details will be described later, but the structure 1 can be used for the following purposes, for example.

By analyzing the liquid film Lf using a spectroscopic analyzer, it is possible to analyze the target component in the liquid L. In other words, the structure 1 can be used as a chip for spectroscopic analysis.
Furthermore, when air or the like is blown from one surface side of the through-hole region 11 of the main body 10 toward the other surface side with the liquid film Lf formed in the through-hole 11, droplets of the liquid film Lf can be sprayed toward the other surface side. In other words, the structure 1 can be used as a liquid spraying tool.
Furthermore, by sucking the liquid film Lf formed in the through-hole 11 with a suction means (e.g., a pipette), it is possible to suck up a volume of the liquid L equal to or larger than the volume of the liquid film L. In other words, the structure 1 can be used as a filtering tool for filtering the liquid L.

The number of through holes 11h can be adjusted as appropriate depending on the application. For example, one or more through holes 11h may be formed. Note that multiple means two or more.

First, we will explain the case where multiple through holes 11h are formed in the through hole area 11 of the main body 10.

In the base material 10a of the main body 10, multiple gaps 10h are formed through which liquid can pass by capillary action. Therefore, when a sample is supplied to one through-hole 11h, the liquid L can be automatically moved (i.e., spread) to the other adjacent through-holes 11h. The liquid L supplied to the through-holes 11h is held in the through-holes 11h by surface tension to form a liquid film Lf. This phenomenon is then carried out continuously in the main body 10, and a liquid film Lf of the liquid L can be formed over the entire through-holes 11h. The amount of liquid L that forms this liquid film Lf depends on the size of the through-holes 11h and the properties of the liquid L, but is a very small amount (for example, about 1 μL to 150 μL) that allows the liquid film Lf to be formed by surface tension.

For this reason, when the structure 1 is used as a spectroscopic chip, the target component in the liquid L can be quantified by analyzing the liquid film Lf formed in the through-hole 11h. Moreover, it becomes possible to obtain homogeneous data from multiple liquid films Lf. In other words, it becomes possible to analyze data from multiple liquid films Lf with a single measurement. In other words, by using the structure 1 for spectroscopic analysis, it becomes possible to accurately quantify the target component in the liquid L even with a small amount of sample.

In addition, when the structure 1 is used as a liquid spraying tool, a plurality of homogeneous droplets can be sprayed onto an object. Furthermore, even if the liquid film Lf disappears, the liquid L is continuously supplied from the opening of the gap 10h as described above into the through hole 11h of the disappeared liquid film Lf, so that the next liquid film Lf is immediately formed. Therefore, when the liquid film Lf is sprayed in the form of droplets, continuous operation is possible.
Moreover, when the liquid film Lf is formed in a spray form for use, uniform and small droplets can be easily formed. Specifically, as described above, such droplets can be formed by a simple structure in which air or the like is blown onto one surface of the through-hole region 11 of the main body 10 of the structure 1.
Therefore, the liquid L can be appropriately applied to the target object to be sprayed. The target of such spraying is not particularly limited. Moreover, since the liquid L can be moved within the base material 10a of the main body 10 to form a liquid film Lf in a filtered state, it is also possible to adjust the quality of the droplets according to the target object to be sprayed.
Furthermore, when the structure 1 is used as a liquid spraying tool as part of an analytical instrument or a spraying instrument, it can function as a nebulizer. For example, if the structure 1 is structured to supply a liquid agent or the like to the liquid supplying section 12 of the main body section 10 of the structure 1, a liquid film Lf can be continuously formed in the through hole 11h. Then, if air or the like is blown toward one surface of the through hole region section 11 of the main body section 10, the liquid agent can be sprayed in a mist form from the other surface. Moreover, the size of the liquid droplets can be controlled by adjusting the size of the through hole 11h. Furthermore, if the material of the structure 1 is made of filter paper or the like described later, the cost can be reduced, so it can be used as a disposable type.

When the structure 1 is used as a filtering tool, continuous suction becomes possible by suctioning the liquid L filtered by the main body 10 from the through-hole 11h with a suction means (e.g., a pipette, etc.). Specifically, by suctioning the liquid film Lf from inside the through-hole 11h with a suction means, continuous suction becomes possible while guiding the liquid L present inside the substrate 10a around the through-hole 11h to the through-hole 11h. This makes it possible to more appropriately suction the liquid L in an amount equal to or greater than the volume of the liquid film L formed in the through-hole 11h.

Next, we will explain the case where one through hole 11h is formed in the through hole area 11 of the main body 10.

Even when there is one through hole 11h, it can be used for the same purpose as when a plurality of through holes 11h are formed, so it may be adjusted appropriately depending on the purpose.
For example, when the structure 1 is used as a filter, the liquid L present inside the base material 10a around the through hole 11h is easily guided to this one through hole 11h. Therefore, it is possible that the suction time of the liquid L in the form of the liquid film Lf can be shortened compared to the case where a plurality of through holes 11h are formed.

In the above example, the liquid L is supplied to the liquid supply section 12 of the main body section 10. However, it goes without saying that the liquid L can be uniformly spread within the through hole 11h to form a liquid film Lf in the same manner as described above even if the liquid L is supplied to one location of the through hole area section 11.

The location where liquid L is dropped in the liquid supply unit 12 may be adjusted as appropriate depending on the amount of impurities in the liquid L. For example, if the amount of impurities in the liquid L is small, the liquid L may be supplied to a location close to the through-hole region 11, whereas if the amount of impurities is large, the liquid L may be dropped to a location as far away as possible from the through-hole region 11.

(Details of Structure 1)
Next, the structure of the structure 1 will be described in detail.

(Substrate 10a)
The base material 10a of the main body 10 of the structure 1 is a plate-like member, and the material is not particularly limited as long as voids 10h are formed therein through which liquid can pass by capillary action.
The substrate 10a may be configured to include only the water-permeable material 10b, or may be configured to include the water-permeable material 10b and the water-impermeable material 10c, or may be configured to include the nanofiber layer 10d made of nanofibers nf and the water-impermeable material 10c, or may be configured to include the water-permeable material 10b, the water-impermeable material 10c, and the nanofiber layer 10d. Details of each material will be described later.

The thickness of the substrate 10a is not particularly limited as long as it does not affect the analysis of the liquid film Lf formed in the through-hole 11h. For example, the thickness of the substrate 10a (the distance between the front surface 10sa and the back surface 10sb of the substrate 10a) is formed to be approximately 0.01 mm to 10 mm.

In particular, when the structure 1 is used as a chip for spectroscopic analysis, in absorptiometry, if the optical path length in the cell is long, the amount of light absorbed by the passing light increases, thereby increasing sensitivity, and the concentration of the target component in the liquid L can be appropriately quantified.
For this reason, in the structure 1, similarly, by lengthening the liquid film length R of the liquid film Lf corresponding to the optical path length, the quantitative determination of the target component in the liquid L can be performed more appropriately. However, if the optical path length, i.e., the length in the thickness direction in the through-hole region 11, is made too long, the transmitted light may be affected by the material of the inner surface of the through-hole 11h. Specifically, not only the light absorption based on the liquid film Lf developed in the through-hole 11h, but also the absorption and scattering of the irradiated light L1 based on the material of the inner surface of the through-hole 11h may cause a decrease in the amount of transmitted light other than the target component in the liquid film Lf, that is, adverse effects on the measurement (decreased sensitivity, deterioration of measurement accuracy). For example, depending on the material of the base material 10a, when the thickness of the through-hole region 11 of the main body 10 is thicker than 10 mm, there is a possibility that non-specific light absorption based on the material of the base material 10a may occur in the measured value. On the other hand, for example, if the thickness in the through-hole region 11 is thinner than 0.01 mm, the liquid film length R of the liquid film Lf becomes shorter, resulting in an excessively short optical path length, which may make it impossible to properly measure the concentration of the target component in the liquid L. Also, if the thickness in the through-hole region 11 is thinner than the above value, the shape of the through-hole 11h becomes more likely to change.
Therefore, from the viewpoint of an analysis method based on absorptiometry, the thickness of the through-hole region 11 of the main body 10 of the structure 1 is, for example, 0.01 mm or more and 10 mm or less. The lower limit of the thickness is preferably 0.05 mm or more, and more preferably 0.1 mm or more. The upper limit of the thickness is preferably 5 mm or less, more preferably 3 mm or less, and even more preferably 1.5 mm or less.

In the case of fluorescence spectroscopy, as in the case of absorptiometry, if the thickness in the through-hole region 11 is made thick, the liquid film length R of the liquid film Lf can be made longer (i.e., the optical path length can be made longer), but there is a possibility that an influence based on the material of the inner surface of the through-hole 11h may occur. Specifically, if the liquid film length R of the liquid film Lf is made too long (i.e., if the thickness in the through-hole region 11 is made too thick), there is a possibility that an influence based on the material of the inner surface of the through-hole 11h may occur in the transmitted light. More specifically, not only the light absorption based on the liquid film Lf developed in the through-hole 11h, but also the adverse effect on the measurement (decreased sensitivity, deterioration of measurement accuracy) similar to the above-mentioned case of absorptiometry may occur. On the other hand, if the thickness in the through-hole region 11 is made too thin, the liquid film length R of the liquid film Lf becomes shorter, resulting in a shorter optical path length and making it impossible to obtain appropriate fluorescence intensity.
Therefore, from the viewpoint of an analysis method based on fluorescence spectroscopy, it is desirable to prepare the structure 1 so that the thickness of the through-hole region 11 of the main body 10 is within the same range as in the case based on absorptiometry.

Furthermore, when the structure 1 is used for color analysis, as in the above-mentioned absorptiometry and fluorescence spectroscopy, if the thickness in the through-hole region 11 is increased, the liquid film length R of the liquid film Lf can be increased (i.e., the optical path length can be increased). If the liquid film length R is increased, the amount of color change based on the absorption or fluorescence derived from the target component in the liquid film Lf can be increased. On the other hand, if the thickness in the through-hole region 11 is made too thick, the transmitted light may be influenced by light based on the material of the inner surface of the through-hole 11h. Specifically, not only the light absorption based on the liquid film Lf developed in the through-hole 11h, but also the light absorption based on the material of the inner surface of the through-hole 11h may cause color changes that are not based on the concentration of the target component in the liquid film Lf, such as color changes or darkening, making it difficult to visually recognize color changes, that is, adverse effects on the measurement (deterioration of measurement accuracy) may occur.
Therefore, from the viewpoint of the analysis method based on the color analysis method, it is desirable to prepare the structure 1 so that the thickness of the through hole region 11 of the main body portion 10 is within the same range as in the case based on the absorptiometry method.

It should be noted that the above example describes a case in which the thickness of the through-hole region 11 of the main body 10 does not change due to swelling or the like of the material of the base material 10a when the liquid L is supplied.
Specifically, the liquid L is supplied so as to fill the entire through-hole 11h, and a substantially uniform liquid film Lf is formed in the through-hole 11h formed in the through-hole region 11 of the main body 10. At this time, the liquid film length R of the liquid film Lf is substantially the same as the length of the through-hole 11h in the through-axis direction in the dry state (i.e., the distance in the thickness direction of the through-hole region 11 of the main body 10). On the other hand, if the material of the base material 10a of the main body 10 absorbs the liquid L and swells, if the liquid L is supplied in the above-mentioned case, the distance in the thickness direction of the through-hole region 11 of the main body 10 will be longer than in the dry state. At this time, the length of the through-hole 11h in the through-axis direction also becomes longer as the base material 10a swells.
Therefore, the liquid film length R of the liquid film Lf becomes longer, and the optical path length also becomes longer than the length of the through-hole 11h in the through-axis direction when the substrate 10a is dry. In other words, even if the thickness of the substrate 10a is thin, it is possible to maintain an optical path length appropriate for analysis by using a material that is easily swollen by the liquid L as the material of the substrate 10a. Therefore, even if the thickness of the substrate 10a is thin, it is possible to appropriately quantify the concentration of the target component in the liquid L by adjusting the material of the substrate 10a.
If the liquid L is supplied so that the liquid film surface Ls of the liquid film Lf has a convex meniscus shape due to the properties of the liquid L, the liquid film length R can be made longer, and therefore the optical path length can also be made longer.

(Size and shape of substrate 10a)
The shape and size of the main body 10 are not particularly limited as long as they do not affect the analysis.
For example, various shapes can be adopted, such as a circular shape, a rectangular shape, a radial shape, a spiral shape, etc. Furthermore, the size can be appropriately adjusted depending on the application, and is not limited to the sizes and shapes described below.
For example, when the structure 1 is used as a chip for spectroscopic analysis, the structure 1 only needs to be large enough to be set in the spectrometer SM, and when it is used as a liquid sprayer, it only needs to be formed into a size that makes it easy to spray liquid.
The shape of the main body 10 is not particularly limited. For example, it can be formed into a square shape with one side of about 0.1 cm to 5 cm, and when it is rectangular, it can be formed so that the short side is about 0.1 cm to 5 cm and the long side is 0.1 cm to 10 cm. Furthermore, when it is circular, it can be formed so that the diameter is about 0.1 cm to 5 cm.

(Vacuum 10h in substrate 10a)
The base material 10a of the main body 10 has a plurality of voids 10h formed therein through which the above-mentioned liquid can pass by capillary action.
The width of the gap 10h inside the base material 10a is not particularly limited as long as the gap 10h is formed so that liquid can pass through it by capillary action. For example, the gap 10h can be formed so that the width is about 0.1 μm to 2000 μm, more preferably 0.2 μm to 1000 μm or less. And, more preferably, the gap 10h is formed so that the width is 0.4 μm to 1000 μm or less, even more preferably 1 μm to 1000 μm or less, and even more preferably 1 μm to 200 μm or less.
In addition, a plurality of voids 10h are formed in a mesh pattern in the substrate 10a. That is, a plurality of voids 10h are formed in a mesh pattern in the substrate 10a such that adjacent voids 10h communicate with each other. In other words, a fine void network through which liquid can pass by capillary action is formed in the substrate 10a.

The proportion of the plurality of voids 10h in the base material 10a is not particularly limited.
For example, the material of the base material 10a may be a commercially available experimental filter paper, filter cloth (felt), nonwoven fabric, etc., which is made of cellulose fiber, which is the water-permeable material 10b. When the base material 10a is formed using such a general material, its porosity (the ratio of the volume of voids 10h per a certain volume of the filter paper, etc.) is about 50% to 95%.
For example, when filter paper is used as the substrate 10a, depending on the material, it is 60% to 95% if it is cellulose-based, 90% if it is silica-based, 50% to 85% if it is polytetrafluoroethylene (PTFE)-based, 80% to 90% if it is glass-based, and 80% to 90% if it is rayon/polyester-based nonwoven fabric.

As described above, the substrate 10a can have various configurations, such as a configuration having only the water-permeable material 10b, a configuration having the aqueous material 12 and the water-impermeable material 10c, a configuration having the nanofiber layer 10d and the water-impermeable material 10c, or a configuration having all of the above.
The materials (permeable material 10b, impermeable material 10c, and nanofiber layer 10d) of the substrate 10a of the main body 10 will be described in more detail below.

(Water permeable material 10b)
The water-permeable material 10b is a fiber assembly in which fine fibers f are bundled, and can be any material that has the property of allowing liquids such as water to permeate into the interior or flow along the surface. Not limited.
The base material 10a may have a structure having a certain degree of porosity by using only the water-permeable material 10b. An example of such a structure is a commercially available filter paper, which will be described later.

The following materials can be used as the water-permeable material 10b.
For example, the fibers f constituting the water-permeable material 10b may be made of natural materials (natural fibers) such as cellulose fibers, fibers, hemp fibers, and pulp fibers, as well as synthetic resin fibers (chemical fibers) made from synthetic resin materials (e.g., polyester, nylon, rayon, acrylic, polypropylene, polyethylene, polyvinyl alcohol, nitrocellulose, carbon, etc.), metal fibers (metal fibers) made from steel wool, copper, silver, etc., and inorganic compound materials such as oxides of silicon and titanium, hydroxides of magnesium, carbonates of calcium, and sulfates of barium. Of course, as described above, a suitable mixture of two or more types may also be used.

The water-permeable material 10b is an assembly of a plurality of the fibers f in a bundle shape. The water-permeable material 10b has fine gaps 10bh between the fibers f that are narrower than the gaps 10h in the substrate 10a. These gaps 10bh have a width of, for example, several μm to several tens of μm. Therefore, when the water-permeable material 10b comes into contact with a liquid such as water, the liquid can penetrate into the fine gaps 10bh between the fibers f. Once the liquid has penetrated between the fibers f, it automatically moves within the gaps 10bh due to the interaction between the liquid and the surfaces of the fibers f that form the gaps 10bh, etc. In other words, the water-permeable material 10b has the function of allowing a sample to penetrate into the interior when it comes into contact with the material, and moving the sample through the gaps 10bh by capillary action.

The substrate 10a is structured to have a predetermined porosity by using only a plurality of the water-permeable materials 10b as described above. In this case, the mesh-like voids 10h of the substrate 10a are formed by a plurality of voids 10h formed between the water-permeable materials 10b and a plurality of gaps 10bh within the water-permeable materials 10b. Examples of substrates 10a having such a structure that can be used include, but are not limited to, the above-mentioned commercially available filter paper (for example, the filter paper described in the examples below), filter cloth (felt), and nonwoven fabric.

In addition, the water-permeable material 10b may contain fine inorganic pigments that are mixed or intentionally mixed as impurities when the water-permeable material 10b itself is manufactured. This is because such fine impurities do not contribute to the formation of a flow path through which the liquid L moves.

(Water-impermeable material 10c)
The impermeable material 10c has the property of preventing liquids such as water from penetrating into it.
The water-impermeable material 10c is disposed between the plurality of water-permeable materials 10b in the substrate 10a.
The material of the impermeable material 10c may be, for example, polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), or other synthetic resin, or may be carbon, glass, silica, metal, or the like. Examples of the material include those made of calcium carbonate, silicon dioxide, etc. In particular, when using an animal's body fluid such as blood as a sample, it is preferable to use the water-impermeable material 10c made of PET, which has low reactivity with such liquids.

The shape of the impermeable material 10c is not particularly limited, and materials having various shapes such as lumps, spheres, short fibers, etc. Also, the impermeable material 10c may be formed by entangling a plurality of fibrous materials.
When the impermeable material 10c is fibrous, its size is not particularly limited. For example, the fibrous impermeable material 10c may have a fiber diameter of about 10 μm to 500 μm and a fiber length of about 20 μm to 5 mm, or a fiber diameter of about 50 μm to 100 μm and a fiber length of about 50 μm to 1 mm.

The substrate 10a is structured to include the fibrous impermeable material 10c and the permeable material 10b as described above. In this case, it is easy to form voids 10h having a predetermined void width within the substrate 10a. The mesh-like voids 10h of the substrate 10a are formed by the voids 10h between the permeable materials 10b, the voids 10h between the permeable materials 10b and the impermeable materials 10c, the voids 10h between the impermeable materials 10c, and the gaps 10bh within the permeable materials 10b. As a result, a more complex mesh-like void 10h is formed within the substrate 10a.

In particular, if the base material 10a has a structure using the water-impermeable material 10c and the water-permeable material 10b, the following advantages are obtained.
First, the substrate 10a is provided with a water-impermeable material 10c. The water-permeable material 13 is disposed between a plurality of water-permeable materials 10b within the substrate 10a. Moreover, the plurality of water-impermeable materials 10c are present non-uniformly (randomly) within the substrate 10a.
For this reason, a plurality of mesh-like voids 10h are formed inside the substrate 10a. That is, a mesh-like void network is formed inside the substrate 10a. The mesh-like voids 10h are formed such that the width of the voids 10h through which the liquid L flows (i.e., the flow path width) changes more (changes non-uniformly) in the direction in which the liquid L flows (flow path direction).
Then, when the liquid L is dropped near the through-hole region of the substrate 10a, the dropped liquid L penetrates into the substrate 10a and moves toward the through-hole 11h while moving through the multiple mesh-like voids 11. Then, while the liquid L moves through the mesh-like voids 10h, impurities are separated and removed. In other words, the substrate 10a of the main body 10 of the structure 1 has a filter function that separates and removes impurities and the like in the liquid L.
Next, the substrate 10a is provided with a water-permeable material 10b. The water-permeable material 10b has therein a plurality of gaps 10bh through which the liquid L can move by capillary action.
Therefore, by including the water-impermeable material 10c and the water-permeable material 10b in the base material 10a, the void network formed therein can be made more complex. In other words, by including the water-permeable material 10b in the base material 10a of the main body 10 of the structure 1, the base material 10a can exhibit a higher filtering function.

As described above, when the structure 1 is used as a spectroscopic chip, the filter function of the base material 10a of the main body 10 increases in the following order: first, when the base material 10a is formed only from the water-permeable material 10b, then when the base material 10a is formed from the water-permeable material 10b and the water-impermeable material 10c, and finally when the base material 10a is formed from the nanofiber layer 10d and the water-impermeable material 10c, which will be described later. In other words, the base material 10a tends to have an unevenness of the internal voids 10h that increases in the same order as the filter function.
For this reason, when quantifying the target component in the liquid L, the target component in the liquid L can be appropriately quantified by appropriately adjusting the structure of the substrate 10a of the main body 10 according to the amount of impurities in the liquid L. Specifically, when analyzing the liquid L containing a large amount of impurities, it is preferable to use a substrate 10a using the water-permeable material 10b and the water-impermeable material 10c or a substrate 10a using a nanofiber layer 10d (described later) and the water-impermeable material 10c, rather than a substrate 10a formed using only the water-permeable material 10b.

(Mixing ratio of water-permeable material 10b and water-impermeable material 10c)
The blending ratio of the water-permeable material 10b and the water-impermeable material 10c constituting the base material 10a is not particularly limited as long as the above-mentioned filtering function can be exhibited.
For example, the blending ratio (mass ratio) of the two may be, for example, water-permeable material 10b:water-impermeable material 10c=1:9 to 9:1.

In the above example, the substrate 10a is configured such that the impermeable material 10c is disposed between the permeable material 10b and the nanofiber layer 10d. However, the substrate 10a may be formed using only the impermeable material 10c. Specifically, the substrate 10a may be formed by entangling a plurality of fibrous impermeable materials 10c to have a structure similar to that of filter paper.

(Nanofiber layer 10d and impermeable material 10c)
Next, a specific example in which the substrate 10a includes the nanofiber layer 10d and the water-impermeable material 10c will be described.
The substrate 10a includes a plurality of nanofiber layers 10d and a plurality of impermeable materials 10c, and has a structure therein including a plurality of nanofiber layers 10d and a plurality of impermeable materials 10c disposed between the plurality of nanofiber layers 10d. As described below, the plurality of nanofiber layers 10d have a plurality of holes penetrating from the front to the back due to the influence of the impermeable materials 10c.

Within the substrate 10a, a plurality of mesh-like voids 10h (mesh-like void networks) are formed between adjacent nanofiber layers 10d, between the nanofiber layers 10d and the impermeable materials 10c, and between adjacent impermeable materials 10c.
The plurality of impermeable materials 10c are arranged so as to be bundled by the plurality of nanofiber layers 10d. By forming a structure in which the plurality of impermeable materials 10c are bundled, the distance between adjacent impermeable materials 10c can be shortened. As a result, the width (flow path width) of the gap 10h between the adjacent impermeable materials 10c can be reduced.
Therefore, by including the nanofiber layer 10d and the impermeable material 10c, the base material 10a of the main body 10 can make the flow path width of the multiple voids 10h formed therein more complex, that is, the void network formed in the base material 10a can be made more complex.
Therefore, by including the nanofiber layer 10d and the impermeable material 10c, the base material 10a of the main body 10 of the structure 1 can exhibit a more excellent filtering function.

The nanofiber layer 10d is a membrane-like material formed from nanofibers nf, which are fine fibers. Specifically, the nanofiber layer 10d is an aggregate in which a plurality of nanofibers nf are entangled and aggregated.
The nanofibers nf constituting the nanofiber layer 10d may be made of synthetic resin or natural materials.

An example of a natural material is cellulose nanofiber nf. This cellulose nanofiber nf has many hydroxyl groups on its surface, so it is more hydrophilic than nanofiber nf made of general synthetic resin that has chemically bonded hydrophilic functional groups. In other words, it has the property of being easily wetted by water.
Therefore, by forming the substrate 10a using a nanofiber layer 10d (cellulose nanofiber layer 10d, sometimes simply referred to as CNF layer 10D) using this cellulose nanofiber nf, it is possible to further improve the capillary action that occurs in the gaps 10h formed between multiple CNF layers 10D.
Therefore, by providing the base material 10a with a plurality of CNF layers 10D, it is possible to obtain an advantage that the movement of the liquid L inside the base material 10a can be made smoother. In other words, by providing the base material 10a with a plurality of CNF layers 10D, it is possible to provide a high water absorption function while providing an excellent filtering function.

The size of such cellulose nanofibers nf is not particularly limited.
For example, fibers having an average fiber diameter of about 1 to 100 nm and an average fiber length of about 100 nm to 1 μm can be used.

The blending ratio of the nanofibers nf, which are the raw material of the nanofiber layer 10d constituting the substrate 10a, and the impermeable material 10c is not particularly limited.
For example, the cellulose nanofibers nf and the impermeable material 10c can be blended in a mass ratio of cellulose nanofibers nf:impermeable material 10c = 1:9 to 9:1.

In addition, the nanofiber layer made of the nanofibers nf generally has a property of being difficult to pass liquids such as water. If the substrate is formed only from such a nanofiber layer, the liquid is repelled by the substrate surface and cannot penetrate into the substrate.
On the other hand, the base material 10a of the main body 10 of the structure 1 is formed using a mixture of the nanofibers nf, which are the raw material of the nanofiber layer 10d, and the impermeable material 10c. Therefore, a plurality of fine holes penetrating from the front to the back are formed in the nanofiber layer 10d disposed inside the base material 10a and on the surface of the base material 10a.
Therefore, even if the substrate 10a of the main body 10 has a nanofiber layer 10d, when the liquid L is dropped onto the surface of the substrate 10a during the supply operation of the liquid L, the dropped liquid L can penetrate into the substrate 10a without being repelled by the nanofiber layer 10d located in the outermost layer (i.e., the surface of the substrate 10a).

In the above example, the base material 10a of the main body 10 has a structure including a water-permeable material 10b, a water-impermeable material 10c, and a nanofiber layer 10d. However, the material of the base material 10a is not limited to these, and as long as it has the above-mentioned void 10h structure, it may contain various additives in addition to these. For example, it may include, but is not limited to, a material that adsorbs impurities in the liquid L, a pigment that has a detachable function, or a material that controls the wettability of the base material.

(Shape retention layer 10e)
The main body 10 of the structure 1 may have a shape-retaining layer 10e for retaining the shape of the base material 10a.
Specifically, the main body 10 may have a structure including a substrate 10a on the front side and a shape-retaining layer 10e located below the substrate 10a and made of a material less likely to swell than the substrate 10a. More specifically, the main body 10 can be formed such that the surface of the shape-retaining layer 10e is in contact with the back surface of the upper layer of the base material 10a, and the back surface functions as the back surface of the main body 10. In the main body 10, the through-hole 11h is formed so as to penetrate the base material 10a and the shape-retaining layer 10e. That is, the rear opening 11hb of the through-hole 11h is formed in the shape-retaining layer 10e of the main body 10. It is formed so as to be located on the back surface of 10e.

For example, in the case where the base material 10a contains an additive or the like (e.g., an acrylic acid polymer gel) that is easily swollen by a solvent or the like in the liquid L, the base material 10a may swell due to the additive or the like when the liquid L is supplied. If the base material 10a swells, the stress is likely to be concentrated in the through-hole 11h.
Here, as the substrate 10a swells, the size of the through-hole 11h (for example, the opening of the through-hole 11h) may change, or the length of the through-hole 11h (the distance between the front opening surface and the back opening surface of the through-hole 11h) may change. If such a phenomenon occurs, when the liquid L is supplied into the multiple through-holes 11h to form a liquid film Lf in the through-holes 11h, the thickness of the liquid film Lf may vary. In other words, when the structure 1 is used as a chip for spectroscopic analysis, the optical path length based on the liquid film Lf formed in each through-hole 11h may vary. If the structure 1 is set in the spectrometer SM in this state and analyzed, the quantitative value of the target component in the liquid L may vary.
However, if the main body 10 of the structure 1 has a shape-retaining layer 10e as described above, the shape-retaining layer 10e can suppress swelling of the base material 10a due to the supply of the liquid L. Therefore, even if the base material 10a of the main body 10 contains an additive or the like that is easily swollen by the liquid L, the target component in the liquid L can be appropriately quantified by forming it to have the above structure.

There are no particular limitations on the material of this shape-retaining layer 10e, so long as it is made of a material that is less likely to swell than the base material 10a, as described above.
For example, the shape-retaining layer 10e may be formed by laminating a plate-shaped member made of paper that does not swell easily (for example, paper having water resistance), resin such as plastic, wood, metal, glass, etc., to the gap layer 11a. The shape-retaining layer 10e may also be formed on the back side of the base material 10a by impregnating the back side of the base material 10a with an adhesive, resin such as plastic, nanofiber dispersion, etc.

When the shape-retaining layer 10e is formed by laminating the above-mentioned plate-like member to the base material 10a, the outer edge of the plate-like member can be formed to have an outer edge portion that protrudes outward beyond the outer edge of the base material 10a. In this case, this outer edge portion can be used as a part to grip when handling, thereby preventing contamination and improving handleability.

(Through hole 11h)
The through-hole 11h of the main body 10 may be formed so as to penetrate from the front to the back of the base material 10a.
For example, the through hole 11h may be formed so that the central axis CL and the surface direction of the base material 10a are perpendicular to each other, or may be formed so as to intersect with each other, which may be appropriately adjusted depending on the application.
For example, when the structure 1 is used as a chip for spectroscopic analysis or as a liquid spraying tool, the through-hole 11h is preferably formed so that the central axis CL is approximately perpendicular to the surface direction of the base material 10a.
Specifically, the through hole 11h is formed penetrating the front and back of the substrate 10a so that the central axis CL of the through hole 11h, which connects the center of the front opening 11ha of the through hole 11h formed on the front surface of the substrate 10a and the center of the back opening 11hb of the through hole 11h formed on the back surface of the substrate 10a, is approximately perpendicular to the substrate 10a surface (front surface 10sa and/or back surface 10sb). By forming the central axis CL of the through hole 11h to be approximately perpendicular to the substrate surfaces 10sa and 10sb, it is possible to improve the accuracy of analyzing the liquid L and improve the accuracy of the spray direction, as will be described in detail later.

When the structure 1 is used as a spectroscopic chip, the length R of the film thickness of the liquid film Lf formed in the through-hole 11h of the main body 10 of the structure 1 corresponds to the optical path length.

In this specification, the phrase "liquid L is spread approximately uniformly in a plurality of through holes 11h" means that approximately the same amount of liquid L is supplied into each through hole 11h and a liquid film Lf of approximately the same thickness is formed in each through hole 11h, and the amount of liquid L spread in the through holes 11h is not particularly limited.
For example, examples of such a state include a state in which liquid L is spread so that the entire inside of each through hole 11h is filled with liquid L, a state in which liquid L is spread to about half of each through hole 11h, and a state in which liquid L is added to about one-third of each through hole 11h, although not shown.

In addition, the length R of the liquid film Lf of the liquid L spread in each through hole 11h (specifically, the length in the thickness direction of the film thickness of the liquid film Lf, hereinafter simply referred to as the liquid film length R) can be measured along the central axis CL of the through hole 11h.
For example, the liquid film length R of the liquid film Lf can be obtained as the distance between the point P where the top surface Lsa of the liquid film Lf intersects with the central axis CL of the through hole 11h and the point Q where the bottom surface Lsb of the liquid film Lf intersects with the central axis CL of the through hole 11h.
For example, when the liquid L is spread so that the upper surface Lsa of the liquid film Lf is substantially flush with the surface 10sa of the substrate 10a and the bottom surface Lsb of the liquid film Lf is substantially flush with the back surface 10sb of the substrate 10a, the length R of the liquid film Lf is substantially the same as the axial length of the through hole 11h (the length of the through hole 11h in the axial direction) In other words, the length R of the liquid film Lf is substantially the same as the distance in the thickness direction in the through hole region of the substrate 10a.

On the other hand, the shape of the liquid film Lf changes depending on the properties of the liquid L.
For example, the liquid film Lf may be formed into a meniscus shape with a convex top surface Lsa or bottom surface Lsb due to the surface tension of the liquid L. In other words, if the amount of liquid L is supplied to the main body 10 so that the through-hole 11h is filled with the liquid film Lf, the liquid film length R of the liquid film Lf will be longer than the axial length of the through-hole 11h. An example of the liquid L that forms such a convex meniscus shape is an aqueous solution with water as the solvent.
Conversely, the liquid film Lf may be formed into a meniscus shape with a concave upper surface Lsa or a concave bottom surface Lsb. If the liquid L is spread over the entire inside of the through hole 11h in the same manner as described above, the length R of the liquid film Lf becomes shorter than the axial length of the through hole 11h.

In the specification, when the through-hole 11h is filled with the liquid L, the liquid surface Ls (upper surface Lsa, bottom surface Lsb) of the liquid film Lf and the substrate surface 10s (front surface 10sa, rear surface 10sb) are in a substantially flat state in a cross-sectional view of the through-hole region of the through-hole region 11. In other words, the flat state in this specification includes not only the state in which the liquid surface Ls of the liquid film Lf and the substrate surface 10s are flush with each other as described above, but also the state in which the liquid film Lf is formed in a convex or concave shape.
In particular, when the structure 1 is used as a filtering tool, it is preferable to form the surface of the liquid film Lf in the through-hole 11h so as to be substantially flat with the substrate surface 10s as described above. In this case, since the inflow of air during suction can be suppressed, the liquid L that has been filtered through the substrate 10a and moved to the through-hole 11h can be easily sucked up with a pipette or the like.

By adjusting the supply amount of liquid L, the structure 1 can form a retention layer on the substrate surface 10s of the main body 10. This retention layer can function as an advantage when the structure 1 is used as a chip for spectroscopic analysis. This is explained below.

When liquid L, which forms the liquid film Lf on the top surface Lsa and bottom surface Lsb in a convex shape, is supplied to the main body 10 so as to fill the multiple through-holes 11h, the convex portions formed to protrude from the front opening 11ha and/or back opening 11hb of the liquid film Lf through-hole 11h may connect with other adjacent convex portions. If this phenomenon occurs throughout the entire liquid film Lf formed in the multiple through-holes 11h, a layer in which the liquid L is stagnating (retention layer) can be formed on the front and/or back surface of the through-hole region of the substrate 10a.

When the structure 1 is used as a spectroscopic chip, the retention layer can lengthen the optical path length. Specifically, the optical path length can be made longer than when the upper surface Lsa of the liquid film Lf is flush with the surface 10sa of the substrate 10a. In other words, the amount of liquid L to be supplied can be increased. Furthermore, the formation of the retention layer can reliably form the liquid film Lf in the multiple through holes 11h.
This makes it possible to improve the sensitivity when measuring the target component in the liquid L. Moreover, since the liquid film Lf is more appropriately formed in the multiple through-holes 11h, the accuracy of the quantitative value of the target component in the liquid L can be further improved.
Therefore, by forming a retention layer on the surface of the substrate 10a, the target component in the liquid L can be measured with good sensitivity, and the concentration in the liquid L can be quantified with high accuracy and stability. In particular, if a plurality of through holes 11h are formed in the substrate 10a of the main body 10 of the structure 1, the concentration of the target component can be calculated from a plurality of liquid films Lf at the same time, and more accurate quantification can be performed. Furthermore, the amount of liquid L used in the liquid film Lf in the structure 1 can be made very small, and a homogeneous liquid film Lf can be formed when the structure has a plurality of through holes 11h. Therefore, even if the sample is small in amount and is not suitable for analysis by the conventional spectroscopic analysis method, the target component in the liquid L can be appropriately quantified by using the structure 1.

The liquid film Lf formed in the through hole 11h is in a state of being held in the through hole 11h. In other words, the material of the liquid film Lf itself is liquid itself.
This makes it possible to suppress the effects of absorption of irradiated light caused by the material of the cell, which occurs when a sample is held in a plastic or glass cell as in the conventional technology. For example, conventional plastic cells cannot be used in the ultraviolet range of 300 nm or less, and organic solvents and strong acids cannot be used. Furthermore, conventional glass or quartz cells cannot be used with strong alkaline solutions.
Therefore, it is no longer necessary to select an analysis method based on the influence of the cell material as in the conventional technology, and therefore there is an advantage that the degree of freedom in analysis can be improved.

In addition, a detection material that reacts with a target component in the liquid L may be supported in the through hole 11h of the base material 10a of the main body 10.
As the detection material, various reaction reagents that cause an antigen-antibody reaction, a fluorescent reaction, or the like, with the target component in the liquid L can be appropriately selected and used. In this case, if a liquid film Lf is formed in the through hole 11h, the detection material reacts with the target component in the liquid film Lf. If this reacted state is measured based on spectroscopic analysis, the target component can be quantified more selectively.

The through hole 11h is formed such that the central axis CL is approximately perpendicular to the base surface 10s of the base material 10a as described above. In this specification, approximately perpendicular means that the angle between the aspect ratio of the through hole 11h (the ratio between the opening width of the through hole 11h and the length of the through hole 11h) is 90 degrees ± 5 degrees.
For example, when the structure 1 is used as a chip for spectroscopic analysis, in order to appropriately quantify the target component in the liquid L, it is preferable to adjust the aspect ratio based on the angle of incidence of the irradiated light L1 incident on the liquid film Lf formed in the through hole 11h and the attenuation rate of the transmitted light L2 so that it is not higher than 11, which is the reciprocal of tan 5° (0.087).
Furthermore, for example, when the structure 1 is used as a liquid sprayer, liquid droplets can be sprayed along the direction of the central axis CL of the through hole 11h, so that liquid L in droplet form can be appropriately sprayed onto a target object.

In addition, when the structure 1 is used as a spectroscopic chip, the irradiation light L1 is irradiated so that the optical axis is approximately perpendicular to the through-hole region 11 of the main body 10 of the structure 1 set in the spectrometer SM. The irradiated irradiation light L1 passes through the liquid film Lf formed in the through-hole 11h of the main body 10 to generate the transmitted light L2. At this time, since the through-hole 11h is formed approximately perpendicular to the substrate surface 10s of the substrate 10a, the liquid film Lf can be formed to be approximately parallel to the optical axis of the irradiation light L1. Therefore, the transmitted light 2 having an optical axis approximately coaxial with the optical axis of the irradiation light L1 irradiated to the liquid film Lf can be formed. Then, the concentration of the target component in the liquid film Lf can be appropriately quantified based on the transmitted light 2. On the other hand, if the angle between the central axis CL of the through-hole 11h and the substrate surface 10s of the substrate 10a is out of the above range, there is a tendency that the appropriate transmitted light L2 cannot be obtained.
Therefore, when the structure 1 is used as a spectroscopic analysis chip, from the viewpoint of appropriately quantifying the target component in the liquid L, it is desirable that the through hole 11h is formed so as to be approximately perpendicular to the substrate surface 10s of the substrate 10a.

When qualifying the target component in the liquid L, the angle may be within the range of 90 degrees ±15 degrees. In other words, when qualifying the target component in the liquid L, it is preferable to adjust the aspect ratio based on the angle of incidence of the irradiated light L1 incident on the liquid film Lf formed in the through hole 11h and the attenuation rate of the transmitted light L2 so that it is not higher than 4, which is the reciprocal of tan 15° (0.268).

(Shape and size of through hole 11h)
The size and shape of the through-hole 11h are not particularly limited as long as they have the function of maintaining the state in which the liquid film Lf is formed by surface tension when the liquid L is supplied into the through-hole 11h.

The through hole 11h may be formed in various shapes, such as a circle, an ellipse, a rectangle, a triangle, or the like.
For example, when the through-hole 11h has a non-circular shape such as a triangular shape or an elliptical shape in which the curvature of a portion of the openings 11ha and 11hb is larger than the curvature of the other portions, the liquid L that has moved through the gap 10h in the substrate 10a tends to enter the through-hole 11h from the portion with the larger curvature when it reaches the inner wall surface of the through-hole 11h. In other words, when a non-circular shape is adopted, the liquid L tends to be more efficiently spread in the through-hole 11h than when the openings 11ha and 11hb are formed into a circular shape.

The size of the through hole 11h is not particularly limited, so long as it is large enough to maintain the liquid L supplied inside as a liquid film Lf by surface tension.

For example, in the case of the substantially circular through-hole 11h, it is preferable that the size of the front opening 11ha and/or the back opening 11hb is 50 μm or more. If the size of the opening of the through-hole 11h is smaller than 50 μm, it tends to be difficult to stabilize the shape of the through-hole 10. On the other hand, although it depends on the viscosity of the liquid L, the upper limit of the size of the through-hole 11h is not particularly limited as long as the liquid film Lf can be formed as described above, but for example, the opening of the through-hole 11h is formed to be smaller than 2000 μm.
Therefore, when the shape of the through hole 11h is substantially circular, the inner diameter of the openings 11ha, 11hb is 50 μm to 2000 μm, more preferably 50 μm to 1000 μm, and further preferably 100 μm to 600 μm.

For example, in the elliptical through hole 11h, the openings 11ha and 11hb are formed so that the major axis (length in the major axis direction) is 50 μm to 2000 μm, and the minor axis (length in the minor axis direction) perpendicular to the major axis is shorter than the major axis, and more preferably, the major axis is 50 μm to 500 μm, and the minor axis is shorter than the major axis.

Furthermore, for example, when filter paper made of cellulose fiber is used as the base material 10a and an elliptical through hole 11h is formed in this base material 10a, the through hole 11h can be formed so that the major axis of the openings 11ha, 11hb is 300 μm to 2000 μm and the minor axis is 250 μm to 1000 μm.
Furthermore, for example, when a filter paper made of glass fiber is used as the base material 10a and an elliptical through hole 11h is formed in this base material 10a, the through hole 11h can be formed so that the major axis of the openings 11ha, 11hb is 350 μm to 2000 μm and the minor axis is 300 μm to 400 μm.
Furthermore, for example, when filter paper made of nitrocellulose fiber is used as the base material 10a and an elliptical through hole 11h is formed in this base material 10a, the through hole 11h can be formed so that the major axis of the openings 11ha, 11hb is 250 μm to 2000 μm and the minor axis is 200 μm to 300 μm.

In particular, when the structure 1 is used as a liquid sprayer, if it is desired that the liquid film L reach the target in the form of droplets, it is preferable that the through-hole 11h is formed so that it has a cone shape from one opening to the other opening. In other words, it is preferable that the shape of the through-hole 11 in the penetrating axial direction is formed so as to have a cone shape.
For example, when the openings of the through-holes 11h (front surface opening 11ha, back surface opening 11hb) are substantially circular and the opening of the through-hole 11 on the side where air or the like is blown is the front surface opening 11ha, the through-holes 11h are formed so as to have a mortar shape from the front surface opening 11ha to the back surface opening 11hb. In other words, the diameter of the front surface opening 11ha of the through-holes 11h is formed to be larger than the diameter of the back surface opening 11hb. If the through-holes 11h are formed in such a shape, there is a tendency for the droplets (the liquid L blown out of the through-holes 11 by air or the like and turned into droplets) to fly straight. In other words, the droplets are easily blown in droplet form along the through-axis of the through-holes 11h without scattering, so that the droplets are easily sprayed appropriately on the target object.

On the other hand, if you want to scatter the droplets while dispersing them, you can make the shape of the through hole 11h the opposite structure to the above. Specifically, if the opening of the through hole 11h (to the front opening 11ha and the back opening 11hb) is approximately circular, and the opening of the through hole 11 on the side where air or the like is blown is the front opening 11ha, the through hole 11h is formed so that it is mortar-shaped from the back opening 11hb to the front opening 11ha. In other words, it is formed in an inverted mortar shape. That is, the diameter of the back opening 11hb of the through hole 11h is formed to be larger than the diameter of the front opening 11ha. If the through hole 11h is formed in such a shape, when the liquid film L is blown out by air or the like, it is possible to blow out the liquid film L in a slightly straight line near the center of the through axis and in a slightly spreading manner around it. In other words, it is possible to spray the droplets while spreading, compared to the case where the liquid film L is blown out in the form of droplets. For this reason, for example, when it is desired to spray droplets over a wide area onto a target object, it tends to be preferable to have the above-described structure for the through-hole 11h.

(Number of through holes 11h)
A plurality of through holes 11h can be formed in the through hole region of the base material 10a, and the number of through holes 11h is not particularly limited.
For example, in the case of a substantially circular through hole 11h having an inner diameter of about 250 μm, or in the case of an elliptical through hole 11h having a major axis of about 300 μm and a minor axis of about 200 μm, the through holes 11h can be formed in the through hole region 11 at a density of 100 to 1000 per ^cm2 .
In particular, if multiple through holes 11h are formed, the number of liquid films Lf will also be multiple, so that when the structure 1 is used as a spectroscopic analysis chip, a large amount of data can be obtained, and when it is used as a liquid spray device, a large amount of droplets can be produced.
Therefore, when the structure 1 is used as a chip for spectroscopic analysis, the quantitative accuracy of the target component in the liquid L can be improved. In addition, by forming a plurality of through holes 11h, it becomes easier to align the liquid film Lf formed in the through holes 11h in the measurement using the spectrometer SM. Therefore, it is possible to improve the operability during analysis. Furthermore, by forming a plurality of through holes 11h, the variation in the obtained quantitative value can be suppressed, so that the variation in the shape of each through hole 11h can be increased to a certain extent. Therefore, the processing accuracy of the through holes 11h can be reduced, so that the productivity of the structure 1 can be improved.
In addition, when the structure 1 is used as a liquid spraying tool, the liquid L formed into fine droplets can be appropriately sprayed onto a target object. Moreover, by forming a plurality of through holes 11h, it becomes easier to align the liquid film Lf with the target object, thereby improving the operability of spraying.

On the other hand, if the through hole 11h is a single hole, it has the advantage that the cost of the base material 10a can be reduced and the processing time for the through hole 11h can be shortened.

The method for forming the through hole 11h is not particularly limited as long as it can achieve the above size and shape.

For example, the through-hole 10 can be formed by laser, mechanical punching, or etching with an acid, a base, an organic solvent, etc. In particular, the formation method using a laser has the advantage that the through-hole 11h can be easily formed so as to be substantially perpendicular to the base material 10a.
In addition, when a material that melts easily due to heat is used as the material of the base material 10a of the main body 10, the material may melt due to the heat of the laser, and the opening of the gap 10h formed on the inner wall surface of the through hole 11h may be blocked. For this reason, when performing laser processing on the base material 10a using such a material, it is desirable to add a process of removing the molten material formed on the inner wall surface with a drill or the like after forming the through hole 11h by laser processing. In this case, it becomes possible to properly expose the openings of the multiple gaps 10h on the inner wall surface of the through hole 11h.

(Liquid diffusion prevention member 30)
The main body 10 of the structure 1 may be structured so as to include a liquid diffusion prevention member 30 on the base surface 10 s of the liquid supply portion 12 .

When the liquid L is supplied, a phenomenon may occur in which the liquid L moves on the substrate surface 10s toward the through-hole region 11 before penetrating into the substrate 10a. If such a phenomenon occurs, a part of the supplied liquid L will penetrate into the through-hole 11h as it is. For this reason, when the objective is to form a liquid film Lf of the filtered liquid L in the through-hole 11h, the occurrence of such a phenomenon is undesirable.
Therefore, in order to allow the main body 10 to properly exhibit the filtering function of the liquid L, it is preferable that the main body 10 of the structure 1 is structured with a liquid diffusion prevention member 30 having a function of preventing the liquid L supplied to the liquid supply unit 12 from moving on the substrate surface 10s toward the through-hole region 11 before it penetrates into the substrate 10a. The liquid diffusion prevention member 30 is a member for preventing the liquid L supplied to the liquid supply unit 12 from moving on the substrate surface 10s and reaching the through-hole 11h formed in the through-hole region 11. In other words, the liquid diffusion prevention member 30 is a member for preventing the unfiltered liquid L from sliding on the substrate surface 10s.

The liquid diffusion prevention member 30 may be provided in any manner so long as it is capable of fulfilling the above-mentioned functions.
For example, the liquid diffusion prevention member 30 can be provided so as to cover the substrate surface 10s at the boundary between the liquid supply section 12 and the through-hole region 11 of the main body 10. Specifically, the liquid diffusion prevention member 30 is a plate-like or film-like member, and can be provided so as to connect both ends along the axial direction of the main body 10 (the liquid supply section 12 and/or the through-hole region 11) so as to intersect with the axial direction of the main body 10 (the direction from the liquid supply section 12 toward the through-hole region 11). In addition, for example, the liquid diffusion prevention member 30 may be provided so that both ends of the plate-like or film-like liquid diffusion prevention member 30 are located near both ends of the main body 10, as long as it exhibits the above function (the function of preventing the unfiltered liquid L from sliding on the substrate surface 10s).
In addition, the position where the liquid diffusion preventing member 30 is provided on the substrate surface 10s is not limited to the above-mentioned boundary portion. For example, the film-shaped liquid diffusion preventing member 30 may be provided so as to cover from the vicinity of the portion where the liquid L is supplied from the liquid supply unit 12 to the vicinity of the adjacent through-hole 11h.

The liquid diffusion prevention member 30 is not particularly limited as long as it has a structure that can perform the above-mentioned functions. For example, the liquid diffusion prevention member 30 can be a film-like or plate-like member as described above, but is not limited to such materials and may be, for example, a structure that forms an upper layer of the substrate surface 10s.

The material of the liquid diffusion prevention member 30 is not particularly limited. Examples include synthetic resins such as plastic, nylon, and polyethylene, as well as paper, natural resin, glass, and nanofiber, but it goes without saying that the material is not limited to these.

In the above example, the liquid diffusion prevention member 30 is provided on the through-hole region 11 side of the liquid supply section 12, but it may be provided in the through-hole region 11 as long as it can perform the above function. For example, the liquid diffusion prevention member 30 may be provided in the through-hole region 11 so as to surround the periphery of the through-hole 11h.

(Cover member 20)
The main body 10 of the structure 1 may be provided with cover members 20 (front cover member 20a, back cover member 20b) on one and/or the other surface in the through hole region 11.
For example, the cover member 20 can be provided so as to cover the openings 11ha, 11hb of the through hole 11h formed in the through hole region 11 of the main body 10. By providing the cover member 20, the three-dimensional shape of the through hole 11h can be stabilized.
This cover member 20 may be appropriately adjusted depending on the application of the structure 1 .

For example, when the structure 1 is used as a spectroscopic chip, the cover member 20 may be provided on both sides of the through-hole region 11 of the main body 10, or may be provided on only one side. When analysis time is required, the cover member 20 can suppress or prevent evaporation of the liquid film Lf. That is, it becomes possible to prevent a change in the concentration of the target component in the liquid L due to the volatilization of the liquid film Lf. For example, when the structure 1 is heated to react the components in the liquid film Lf, the liquid film Lf formed in the through-hole 11h is likely to volatilize, but the cover member can prevent such volatilization. Therefore, when time is required until measurement after the liquid film Lf is formed, the target component in the liquid L can be more appropriately quantified by using a structure provided with a cover member. Moreover, since the cover member 20 can prevent fluctuations in the thickness of the liquid film Lf formed in the through-hole 11h, it becomes possible to further improve the quantitation of the target component in the liquid L.
When the structure 1 is used as a chip for spectroscopic analysis, the material of the cover member 20 is not particularly limited as long as it is optically transparent, and for example, plastic, glass, nanofiber, etc. can be used.

For example, when the structure 1 is used as a filtering tool, a cover member 20 can be provided on the surface opposite to the surface on which the liquid film Lf formed in the through-hole 11h is sucked by the suction means. In this case, when the liquid film Lf formed in the through-hole 11h is sucked by the suction means, the cover member 20 can prevent air bubbles from being mixed in. This makes it possible to perform continuous suction appropriately. Note that when the structure 1 is used as a filtering tool, the material of the cover member 20 is not particularly limited.

Furthermore, for example, when the structure 1 is used as a liquid sprayer, a cover member 20 can be provided in which a hole penetrating from the front to the back is formed at the location of the through hole 11h. The location of the through hole 11h includes not only the location corresponding to each through hole 11h, but also the location where multiple through holes 11h are grouped together. For example, a cover member formed so that multiple through holes 11h are located inside one hole of the cover member 20 can be provided in the through hole area 11. In this case, the range of the sprayed droplets can be adjusted by the hole in the cover member 20. When the structure 1 is used as a liquid sprayer, the material of the cover member 20 is not particularly limited.

When the structure 1 is used as a filtering tool or a chip for spectroscopic analysis, the cover member 20 may carry a reagent that is advantageous for detection or filtration. In other words, the portion corresponding to the through-hole 11h of the cover member may be used as a reaction field. Specifically, in this reaction field, a detection material such as a reaction reagent that binds to the target component in the liquid L and an anticoagulant that is advantageous for filtration are provided on the inner surface (the surface facing the through-hole region 11) of the cover member 20 (front cover member 20a and/or back cover member 20b). The method of providing the detection material on the cover member 20 is not particularly limited, and for example, the detection material can be provided by carrying or holding it. As a method of holding or holding the detection material on the cover member 20, a method of applying the detection material to the inner surface of the cover member and drying it can be adopted. Then, when the liquid comes into contact with the surface held by the cover member 20, the applied detection material is dissolved. Then, the liquid L supplied to the liquid supply unit 12 of the structure 1 reaches the through hole 11h and forms a liquid film Lf. When the liquid surface of this liquid film Lf comes into contact with the inner surface of the cover member 20, a detection material advantageous for detection can be eluted from the cover member 20 into the liquid film Lf. If a target component is present in the liquid film Lf, the target component and the detection material can be bonded. If this detection material absorbs a specific wavelength in the irradiated light L1, light absorption based on the target component in the liquid film Lf occurs in the spectroscopic analysis, so that the target component in the liquid L can be more appropriately quantified. In addition, by sucking up the reacted liquid film Lf with a suction means, a liquid L containing the reacted target component can be obtained.

For example, when a detection material is supported on the inner surface of the cover member 20, the target component can be adsorbed or bound to the detection material supported on the inner surface of the cover member 20. In other words, the target component can be held directly on the inner surface of the cover member 20, so that by irradiating the liquid film Lf in such a state with irradiation light L1, the target component can be appropriately quantified in the same manner as described above.

Furthermore, as a method of providing the detection material on the cover member 20, the detection material may be present on the surface and inside of the cover member 20. For example, the cover member 20 is formed by mixing the detection material with the material (e.g., plastic, nanofiber nf, etc.) that forms the cover member 20. By using this cover member 20, the target component can be adsorbed or bound to the inner surface of the cover member 20 and the detection material located slightly inside from the inner surface of the cover member 20. In this case, light absorption and the like can be caused on the inner surface and inside of the cover member 20. In this case, the target component in the liquid L can be more stably and appropriately quantified.

<Spectroscopic analysis using structure 1>
Spectroscopic analysis when the structure 1 is used as a chip for spectroscopic analysis will be described.
First, an overview of the spectrometer SM and the like will be given, followed by a detailed description.

In the specification, the term "spectroscopic analysis" refers to a method for analyzing a target component in a sample based on the light obtained by irradiating the sample with light, and various methods can be used to analyze the light obtained. For example, spectrophotometry, fluorescence spectroscopy, color analysis, etc. can be used as the analytical method.

(Spectrometer SM)
The symbol SM in the figure indicates a spectrometer used for spectroscopic analysis.
The spectrometer SM comprises a stage having a measurement window for placing the structure 1, a light source means for irradiating irradiation light L1 onto a liquid film Lf formed in the through hole 11h of the through hole area 11 of the main body 10 of the structure 1 placed in the measurement window of the stage, a light receiving means for receiving transmitted light L2 that is the light irradiated from the light source means and transmitted through the liquid film Lf, and an analysis means for analyzing the light received by the light receiving means.

The measurement window on the stage of the spectrometer SM is formed to communicate between the front and back of the stage of the spectrometer SM, and serves as a communication hole for measurement to place and hold the structure 1 .
The light receiving means and the analyzing means used in the spectrometer SM may be those based on absorptiometry, fluorescence spectroscopy, color analysis, or the like.
Hereinafter, the analysis of a target component in liquid L using each analysis method will be described in order.

(When using spectrophotometry or fluorescence spectroscopy)
First, the case where absorptiometry or fluorescence spectroscopy is used will be described.
In the spectrometer SM, a light source means and a light receiving means are disposed on either side of a measurement window of the stage.
The light source means includes a light source and a light irradiating fiber for irradiating light emitted from the light source. The light irradiating fiber is connected at its base end to the light source and is configured to irradiate the light from the light source from an irradiation surface at its tip as irradiation light L1.
The light receiving means includes a light irradiating fiber and a light receiving optical fiber that receives the transmitted light (transmitted light L2) from the light irradiating fiber, which passes through (transmits) the liquid film Lf formed in the through hole 11h of the through hole region 11 of the main body 10 of the structure 1 and is disposed in the measurement window. The base end of the light receiving optical fiber is connected to the analysis means, and the transmitted light L2 received at the light receiving surface at the tip can be transmitted to the analysis means. The analysis means has a function of converting the light transmitted from the light receiving optical fiber of the light receiving means into a data signal and calculating the concentration of the target component in the liquid L based on the converted data signal.

The method of installing the light emitting fiber and the light receiving fiber is not particularly limited.
For example, the light-illuminating fiber and the light-receiving fiber can be arranged so that the light-receiving surface of the light-receiving fiber is located on the optical axis of the light-illuminating fiber through the measurement window. Specifically, the light-illuminating fiber is arranged below the measurement window. At this time, the light-illuminating fiber is arranged so that the irradiation surface of the light-illuminating fiber faces the opening surface of the measurement window. In other words, the light-illuminating fiber is arranged so that the optical axis of the irradiation light L1 irradiated from the irradiation surface is perpendicular to the opening surface of the measurement window. The light-receiving fiber is arranged at the opposite position to the position where the light-illuminating fiber is installed, that is, above the measurement window, so that the transmitted light L2 that is irradiated from the irradiation surface of the light-illuminating fiber and transmitted through the liquid film Lf of the through-hole region 11 of the main body 10 can be received at the light-receiving surface.
Then, by arranging the through hole area 11 of the main body 10 of the structure 1 in the measurement window of the spectrometer SM, the structure can be set up so that, from the bottom, the irradiation surface of the light-irradiating fiber, the through hole area 11 of the main body 10 of the structure 1, and the light-receiving surface of the light-receiving fiber are positioned in that order.

Then, in this spectrometer SM, when the irradiation light L1 is irradiated, the through hole 11h (the liquid film Lf formed in the through hole 11h) of the through hole area 11 of the main body 10 and the light receiving surface of the light receiving optical fiber can be set so that they are positioned in the irradiation area of the irradiation light L1.Then, the light receiving optical fiber can be set so that the transmitted light L2 that has passed through the liquid film Lf can be appropriately received at the light receiving surface.

When calculating the concentration of a target component in liquid L based on absorptiometry, it is desirable to provide a monochromator. This monochromator has the function of selecting light of a specific wavelength from the light irradiated from the light source, and is provided between the light source and the irradiation surface at the tip of the light irradiating fiber. For example, a prism, a diffraction grating, an optical filter, etc. can be used as the monochromator. When a prism is used, there is an advantage that electromagnetic waves (light) in a wide wavelength band can be selected.

Furthermore, when calculating the concentration of the target component in the liquid L based on fluorescence spectroscopy, it is desirable to appropriately adjust the positional relationship between the optical axis of the irradiating light L1 and the light-receiving surface of the light-receiving fiber.
Specifically, the optical system is arranged so that the irradiation light L1 (called excitation light in the fluorescence spectroscopy analysis method, hereinafter referred to as excitation light L1 in this analysis method) irradiated from the light irradiating fiber does not directly enter the receiving fiber. By arranging in this manner, the fluorescence analysis can be performed appropriately. More specifically, the excitation light L1 irradiated from the light irradiating fiber causes the target component in the liquid film Lf formed in the through-hole 11h of the through-hole region 11 of the main body 10 of the structure 1 to emit fluorescence. This fluorescence is shifted to the long wavelength side with respect to the irradiated excitation light L1. Then, by appropriately detecting the fluorescence based on this target component, the concentration of the target component can be appropriately quantified. For this purpose, the following configuration is adopted.
For example, an optical filter that removes light components on the low wavelength side from the transmitted light L2 that has passed through the liquid film Lf formed in the through-hole region 11 of the main body 10 is disposed between the through-hole region 11 of the main body 10 and the receiving optical fiber. Alternatively, since the fluorescence based on the target component is emitted in random directions, the receiving surface of the receiving optical fiber is disposed in a direction that is offset from the optical axis of the excitation light L1 irradiated from the light-irradiating fiber (for example, a direction perpendicular to the traveling direction of the excitation light L1 irradiated from the light-irradiating fiber).

(When using color analysis)
Next, the case where color tone analysis is used will be described.
When color analysis is used, an optical microscope is provided on the opposite side of the light emitting fiber instead of the light receiving fiber.
This configuration is not particularly limited as long as it is a configuration that allows observation of the state of the liquid film Lf formed in the through-hole 11h of the through-hole region 11 of the main body 10 of the structure 1 with an optical microscope.
For example, the optical microscope has a base end connected to an analysis means, and is capable of digitizing the image of the liquid film Lf observed within the through hole 11h of the through hole area 11 of the main body 10 and transmitting it to the analysis means.
This analysis means has a function of calculating, based on image data transmitted from the optical microscope, the concentration of the target component in the liquid L. For example, this analysis means has a function of analyzing coloring based on the image data transmitted from the optical microscope using a color space (a color system such as RGB or L*A*B* (L-star-A-star-B-star)), and calculating the concentration of the target component in the liquid L from the obtained value.

The structure 1 in which the liquid film Lf of the liquid L is formed in the through-hole 11h of the through-hole region 11 of the body 10 is set in the spectrometer SM configured as described above, and the through-hole region 11 of the body 10 is irradiated with irradiation light L1. The irradiated irradiation light L1 passes through the liquid film Lf formed in the through-hole 11h to generate transmitted light L2. Then, by analyzing this transmitted light L2 by spectroscopic analysis, the concentration of the target component in the liquid L can be appropriately quantified. That is, the body 10 of the structure 1 exerts a function similar to that of a cell used in conventional spectroscopic analysis. Specifically, the base material 10a of the body 10 of the structure 1 corresponds to a cell used in conventional spectroscopic analysis. And the liquid film Lf formed in each through-hole 11h of the base material 10a corresponds to a sample contained in a conventional cell.
Therefore, even though the base material 10a of the main body 10 is not formed from a transparent material that transmits light, such as quartz, glass, or plastic, the structure 1 is capable of quantifying the target component in the liquid L using the same principle as conventional spectroscopic analysis.

(Quantitative Determination of Target Component in Liquid L Based on Absorption Spectrophotometry)
In the following, first, a detailed description will be given of a representative case in which a target component in liquid L is quantified based on absorptiometry among spectroscopic analysis methods.

The amount of liquid L supplied to the through-holes 11h of the main body 10 will be described as being such that the entire inside of each through-hole 11h is filled with liquid L and a liquid film Lf is formed throughout the entire inside of the through-holes 11h.

Furthermore, the spectrometer SM and structure 1 described below are described as representative examples, and the spectrometer SM and structure 1 are not limited to the structure and configuration shown below.

The spectrometer SM has a light emitting fiber located below the stage and a light receiving fiber provided above the stage on the opposite side across a communication hole.
The main body 10 of the structure 1 is made of filter paper (having a predetermined porosity) and is formed into a rectangular shape with short sides of about 50 mm and long sides of 150 mm. The main body 10 has a through-hole region 11 with one side being about 5 mm square on one short side, and is formed so as to have a liquid supply portion 12 on the other short side continuous with the through-hole region 11.
In the through hole region 11 of the main body 10, circular through holes 11h having a diameter of about 100 μm to 1000 μm are formed at a density of 200 to 300 holes/cm ² .

(Development of Liquid L)
First, a predetermined amount of liquid L is supplied to the liquid supply portion 12 of the main body portion 10 , and the liquid L is spread up to the through-hole region 11 of the main body portion 10 .
The supplied liquid L permeates into the substrate 10a from the vicinity of the surface where it was dropped. The liquid L that has permeated into the substrate 10a from the surface moves toward the through holes 11h of the through hole region 11 while moving through the voids 10h formed in the substrate 10a by capillary action.
The plurality of voids 10h in the substrate 10a are formed so that the liquid can pass through them by capillary action. Therefore, the liquid L that has entered the voids 10h automatically moves within the voids 10h so as to move away from the dripping position. The voids 10h are formed in communication with the plurality of through holes 11h. That is, the inner wall surface of the through holes 11h has an opening for the countless voids 10h. Therefore, when the liquid L that has moved within the voids 10h reaches one of the through holes 11h, it enters the through hole 11h from the opening of the void 10h formed on the inner wall surface of the through hole 11h, and the liquid L is supplied to the through hole 11h so as to spread along the inner wall surface. Finally, the liquid L that has entered the through hole 11h forms a liquid film Lf so as to block the through hole 11h due to the surface tension of the through hole 11h. Meanwhile, the through hole 11h is communicated with the adjacent through holes 11h by the plurality of voids 10h. Therefore, the liquid L that has penetrated into one through hole 11h moves to the adjacent through hole 11h while maintaining the length of the liquid film Lf at a length approximately the same as the thickness of the through hole area portion 11 of the substrate 10a (the distance in the thickness direction of the substrate 10a).

As this phenomenon occurs continuously, the liquid L is spread almost uniformly into the multiple through holes 11h formed in the through hole region of the through hole region portion 11 of the main body portion 10, and an almost uniform liquid film Lf is formed within each through hole 11h.
Furthermore, the liquid film Lf formed in the through hole 11h is formed so that its front and back surfaces are approximately flat relative to the surface of the through hole region, so that the length of the liquid film Lf can be made approximately the same as the distance along the line in the penetrating axis direction of the through hole 11h (i.e., the thickness of the penetrating region of the substrate 10a).

Therefore, if liquid L is supplied dropwise to the liquid supply section 12 of the main body section 10 of the structure 1, the liquid L can be spread into the multiple through-holes 11h while automatically moving through the gaps 10h formed inside the base material 10a of the main body section 10 by capillary action, and a homogeneous liquid film Lf can be formed in each through-hole 11h. In other words, multiple liquid films Lf with uniform optical path lengths can be formed in the through-hole area section 11 of the main body section 10.

(Measurement and Quantification)
The structure 1 is set on the stage of a spectrometer SM.
At this time, the structure 1 is placed so that the through-hole region 11 of the main body 10 is positioned above the opening of the communication hole of the stage. Since the through-hole 11h is formed so as to be perpendicular to the base material 10a, the liquid film Lf can be arranged so as to be parallel to the optical axis of the irradiation light L1.
In this state, the light source is operated to irradiate the through-hole region 11 of the main body 10 of the structure 1 with irradiation light L1 from the light-irradiating fiber.
The irradiated light L1 passes straight through the liquid film Lf formed in the through hole 11h from the lower surface to the upper surface thereof. If a substance that reacts to the irradiated light L1 is present in the liquid film Lf, the irradiated light L1 incident on the liquid film Lf and the transmitted light L2 that has passed through the liquid film Lf will have different light components.

The transmitted light L2 transmitted through the liquid film Lf is received by the light receiving surface of a light receiving optical fiber provided above the stage of the spectrometer SM. The transmitted light L2 received by the light receiving optical fiber is sent to an analyzing means.
The analyzing means converts the transmitted light L2 transmitted from the light receiving optical fiber into a data signal, and the concentration of the target component in the liquid L is calculated (i.e., quantified) based on the converted data signal.

As described above, first, the liquid L is supplied to the liquid supply portion 12 of the main body portion 10 of the structure 1 to form a liquid film Lf in each through hole 11h of the through hole region portion 11. Each liquid film Lf is held in each through hole 11h in approximately the same state.
By setting this main body 10 in a spectrometer SM, the concentration of a target component in the liquid L can be quantified based on the transmitted light L2 obtained from the liquid film Lf. In other words, in the main body 10, a sample having an optical path length required for spectroscopic analysis can be formed in a uniform state.
Therefore, the main body 10 of the structure 1 can function similarly to a transparent cell made of quartz, glass, or the like used in conventional spectroscopic analysis. Moreover, even though the size of the through-hole 11h for supplying the liquid L is small (e.g., about 50 μm), the target component in the liquid L can be quantified with high accuracy based on the spectroscopic analysis.

The concentration can be calculated based on a general method for spectrophotometry. For example, the concentration of a target component in a sample may be calculated using a calibration curve method or a standard addition method prepared based on the relationship between absorbance and concentration, or may be calculated by an internal standard method in which an internal standard substance is added to a sample.
In addition, in the measurement of liquid L, it is desirable to perform a blank measurement in advance using the same structure 1. Specifically, if a blank sample not containing the target component is prepared and the same analysis as that of liquid L is performed using the same structure 1, it is possible to correct background absorbance caused by the structure 1, and thus it is possible to suppress data variation, etc., and thus it is possible to obtain an advantage that the accuracy of the quantitative analysis of the target component can be further improved.

In addition, by simply dripping the liquid L into the liquid supply section 12 of the main body section 10, the liquid L can be automatically and uniformly supplied into the multiple through holes 11h, which has the advantage of eliminating the need for a complicated structure for supplying the liquid L.

Furthermore, the supplied liquid L moves within the substrate 10a of the main body 10 by capillary action and is held within the through-holes 11h by surface tension, so the sample can be moved into the substrate 10a of the main body 10 even if the structure 1 is not maintained horizontally (for example, even if the substrate 10a of the main body 10 is fixed vertically). Therefore, regardless of the arrangement state of the structure 1, a homogeneous liquid film Lf can be formed within the multiple through-holes 11h formed in the main body 10.

(Quantitative Determination of Target Component in Liquid L Based on Color Analysis)
Next, a detailed description will be given of a case where a target component in liquid L is quantified using color analysis, which is one of the spectroscopic analysis methods.

As described above, the structure 1 is set on the stage of the spectrometer SM, and the irradiation light L1 is irradiated from the light irradiation fiber to the main body 10. Then, the liquid film Lf formed in the multiple through holes 11h changes color depending on the concentration of the target component in the liquid L. The color analysis of this embodiment is a technique for quantifying the target component in the liquid L based on the change in color of the changed liquid film Lf.

The optical microscope has a base end connected to an analysis means, and is capable of converting the observed image of the liquid film Lf formed in the through-hole 11h into digital data and transmitting it to the analysis means.
The analysis means calculates the concentration of the target component in the sample based on the image data. Specifically, the analysis means uses color space (color space such as RGB or L ^* A ^* B ^* (L-star-A-star-B-star)) for coloring based on the image data, thereby enabling the concentration of the target component in the sample to be calculated.
In other words, the target component and its concentration present in the sample (i.e., in the liquid film Lf) have their own absorption wavelength and absorption amount specific to the component, so it is possible to identify and quantify the substances in the sample from the color tone based on the image data observed by the optical microscope.

The optical microscope can freely adjust the magnification, so that it is possible to analyze the color tone of the liquid film Lf formed in one of the multiple through-holes 11h in the through-hole region 11 of the main body 10. In this case, it is possible to identify and quantify the substance in the sample regardless of the diameter of the through-hole 11h.
On the other hand, the color tones of the liquid film Lf formed in the multiple through holes 11h may be added together and averaged. By averaging the data, it is possible to improve the quantitation and reproducibility of the target component in the sample. In other words, by using the structure 1, the concentration of the target component in the sample can be appropriately quantified based on the color tone analysis even with a small amount of sample.

The light irradiated from the light-irradiating fiber may be of a single wavelength or white light. When the target component to be measured is limited, monochromatic light (e.g., LED) near the maximum absorption wavelength of that component may be used. When multiple target components are measured simultaneously or time-resolved measurements are performed to dynamically observe the reaction of the target components, white light with a wide range of wavelengths may be used.

The concentration of the target component in a sample can be calculated, for example, by quantifying the color tone in the XY color system or Lab color system, expressing it on a two-axis plane or three-axis space, measuring a solution of known concentration, and calculating the concentration of the target component in the sample from the correlation between the concentration and the numerical value based on the color tone.

Furthermore, as described above, when the main body 10 of the structure 1 is provided with the cover member 20, a substance may be provided that reacts with a target component in a sample to produce coloration or the like when a liquid film Lf is formed in the through-hole 11h. For example, if a reaction reagent that reacts with a target component in a sample to produce coloration or the like is supported on the inner surface of the cover member 20 (i.e., the surface located on the front or back side of the base material 10a), it can react with the concentration of the target component in the sample.
Then, even if the concentration of the target component is low, it becomes possible to quantify the target component in the sample based on the color change such as coloration. Moreover, even if the target component in the sample does not react with the irradiated light, it becomes possible to calculate the concentration of the target component by providing a reaction reagent, thereby improving the flexibility of analysis.

<Liquid filtering method using structure 1 as a filtering tool>
A liquid filtering method using the structure 1 as a filtering tool will be described.
First, an overview will be given.
The liquid L is supplied to the liquid supply section 12 of the structure 1. The liquid L moves in the substrate 10a toward the through-hole region 11, and forms a liquid film Lf in the through-holes 11h formed in the through-hole region 11. The liquid film Lf is sucked using a suction means such as a pipette, thereby obtaining a filtered liquid L. Moreover, the obtained amount of the filtered liquid L is characterized in that it is possible to obtain an amount equal to or greater than the volume of the liquid film Lf.

A substrate 10a having a shape-retaining layer 10e can be used for the main body 10 of the structure 1. Specifically, the substrate 10a containing the nanofiber layer 10d and the water-impermeable material 10c is formed so as to be laminated on the surface of the shape-retaining layer 10e.
The size and shape of the main body 10 are formed in a rectangular shape with short sides of about 50 mm and long sides of 150 mm. The main body 10 has a through hole region 11 with one side of about 5 mm square on one short side, and is formed to have a liquid supply unit 12 on the other short side continuous with the through hole region 11. The liquid supply unit 12 is provided with a liquid diffusion prevention member 30 on the substrate surface 10s. The liquid diffusion prevention member 30 is formed in a square shape with one side of about 5 mm, which is approximately the same as the length of the short side of the main body 10. In other words, the main body 10 has a structure in which the substrate surface 10s on the through hole region 11 side of the liquid supply unit 12 is covered with the liquid diffusion prevention member 30.
A through hole 11h is formed in the through hole region 11 of the main body 10. A cover member 20 (rear cover member 20b) is provided on the rear surface side of the through hole region 11 so as to cover a rear surface opening 11hb of the through hole 11h.
The through hole 11h is formed in the through hole region 11 so that the center of the through hole 11h is located at a position 3 mm to 5 mm from the nearby short side of the main body 10 (the short side opposite the liquid supply part 12). The number of the through hole 11h formed is one, and it is formed in a circular shape with a diameter of about 1000 μm. In other words, the main body 10 is configured in the order of a portion where the liquid L is supplied from one short side to the other short side, the liquid diffusion prevention member 30, and the through hole 11h in a plan view.

(Development of Liquid L)
First, a predetermined amount of liquid L is supplied to the liquid supply portion 12 of the main body portion 10 , and the liquid L is spread up to the through-hole region 11 of the main body portion 10 .
The supplied liquid L permeates into the substrate 10a from the vicinity of the surface where it was dropped. At this time, some of the liquid L slides on the substrate surface 10s and attempts to move to the through-hole region 11, but this movement is prevented by the liquid diffusion prevention member 30. Therefore, all of the supplied liquid L can be made to permeate into the substrate 10a from the substrate surface 10s in the vicinity of where it was dropped.
The liquid L that has permeated into the substrate 10a from the surface to the inside moves toward the through holes 11h of the through hole region 11 while moving through the voids 10h formed in the substrate 10a due to capillary action.
The plurality of voids 10h in the substrate 10a are formed so that the liquid can pass through them by capillary action. Therefore, the liquid L that has entered the voids 10h automatically moves within the voids 10h so as to move away from the dripping position. The voids 10h are formed in communication with the plurality of through holes 11h. That is, the inner wall surface of the through holes 11h has an innumerable number of openings of the voids 10h. Therefore, when the liquid L that has moved within the voids 10h reaches one of the through holes 11h, it enters the through hole 11h from the opening of the void 10h formed on the inner wall surface of the through hole 11h, and the liquid L is supplied to the through hole 11h so as to spread along the inner wall surface. Then, finally, the liquid L that has entered the through hole 11h forms a liquid film Lf so as to block the through hole 11h due to the surface tension of the through hole 11h. Meanwhile, the liquid L that has moved within the voids 10h so as to surround the periphery of the through hole 11h is present in the through hole region 11.

(Suction method)
Next, the liquid film Lf formed in the through hole 11h of the through hole region 11 is sucked by using a suction means. The suction means can be one whose tip size is approximately the same as or slightly smaller than the opening of the through hole 11h. For example, a commercially available micropipette or the like can be used as the suction means. The tip of the suction means is inserted into the through hole 11h, and the liquid film Lf formed in the through hole 11h is sucked. At this time, since the rear opening 11hb of the through hole 11h is covered with the cover member 20 (rear cover member 20b), it is possible to prevent the liquid L from leaking out from the rear opening 11hb of the through hole 11h during suction, and to prevent air bubbles from being mixed in when the liquid film Lf is sucked. Therefore, by continuing the suction, the liquid L can be sucked by the capillary phenomenon based on the openings of the countless voids 10h on the inner wall surface of the through hole 11h, and the liquid L can be sucked by the capillary phenomenon based on the openings of the countless voids 10h on the inner wall surface of the through hole 11h. In other words, by using the structure 1, the filtered liquid L can be easily collected by the weak reduced pressure of the suction means.

<Liquid spraying method using structure 1 as a liquid spraying tool>
A liquid spraying method using the structure 1 as a liquid spraying tool will be described.
First, an overview will be given.
The liquid L is supplied to the liquid supply section 12 of the structure 1. The liquid L moves toward the through-hole region 11 in the base material 10a, and forms a liquid film Lf in the through-hole 11h formed in the through-hole region 11. In this state, air or the like is blown from one surface side of the through-hole region 11 to the other surface side. Then, the liquid film Lf is separated from the through-hole 11h by the air or the like and becomes droplets, and moves toward the blowing direction together with the air or the like. If an object exists in the blowing direction, the droplets formed from the liquid film Lf can be applied to the object. In other words, if the structure 1 is used as a liquid spraying tool, the liquid film Lf can be applied to the object in a state in which it is formed into droplets, and further, it is characterized in that fine droplets can be easily formed without using a special liquid delivery device or a special device for forming fine droplets.

A base material 10a having a shape-retaining layer 10e can be used for the main body 10 of the structure 1. Specifically, filter paper is used as the material for the base material 10a, and the main body 10 is formed by laminating the base material 10a on the surface of the shape-retaining layer 10e.
The size and shape of the main body 10 are formed in a rectangular shape with short sides of about 50 mm and long sides of 150 mm. The main body 10 has a through hole region 11 with one side of about 5 mm square on one short side, and is formed to have a liquid supply unit 12 on the other short side continuous with the through hole region 11. The liquid supply unit 12 is provided with a liquid diffusion prevention member 30 on the substrate surface 10s. The liquid diffusion prevention member 30 is formed in a square shape with one side of about 5 mm, which is approximately the same as the length of the short side of the main body 10. In other words, the main body 10 has a structure in which the substrate surface 10s on the through hole region 11 side of the liquid supply unit 12 is covered with the liquid diffusion prevention member 30.
In the through hole region 11 of the main body 10, circular through holes 11h having a diameter of about 100 μm to 1000 μm are formed about 1 mm inward from each edge at a rate of 200 to 300 pcs/cm ² .
The main body 10 may have a structure in which the liquid diffusion prevention member 30 is not provided.

(Development of Liquid L)
First, a predetermined amount of liquid L is supplied to the liquid supply portion 12 of the main body portion 10 , and the liquid L is spread up to the through-hole region 11 of the main body portion 10 .
The supplied liquid L permeates into the substrate 10a from the vicinity of the surface where it was dropped. At this time, some of the liquid L slides on the substrate surface 10s and attempts to move to the through-hole region 11, but this movement is prevented by the liquid diffusion prevention member 30. Therefore, all of the supplied liquid L can be made to permeate into the substrate 10a from the substrate surface 10s in the vicinity of where it was dropped.
The liquid L that has permeated into the substrate 10a from the surface to the inside moves toward the through holes 11h of the through hole region 11 while moving through the voids 10h formed in the substrate 10a due to capillary action.
The plurality of voids 10h in the substrate 10a are formed so that the liquid can pass through them by capillary action. Therefore, the liquid L that has entered the voids 10h automatically moves within the voids 10h so as to move away from the dripping position. The voids 10h are formed in communication with the plurality of through holes 11h. That is, the inner wall surface of the through holes 11h has an opening for the countless voids 10h. Therefore, when the liquid L that has moved within the voids 10h reaches one of the through holes 11h, it enters the through hole 11h from the opening of the void 10h formed on the inner wall surface of the through hole 11h, and the liquid L is supplied to the through hole 11h so as to spread along the inner wall surface. Finally, the liquid L that has entered the through hole 11h forms a liquid film Lf so as to block the through hole 11h due to the surface tension of the through hole 11h. Meanwhile, the through hole 11h is communicated with the adjacent through holes 11h by the plurality of voids 10h. Therefore, the liquid L that has penetrated into one through hole 11h moves to the adjacent through hole 11h while maintaining the length of the liquid film Lf at a length approximately the same as the thickness of the through hole area portion 11 of the substrate 10a (the distance in the thickness direction of the substrate 10a).

As this phenomenon occurs continuously, the liquid L is spread almost uniformly into the multiple through holes 11h formed in the through hole region of the through hole region portion 11 of the main body portion 10, and an almost uniform liquid film Lf is formed within each through hole 11h.
Furthermore, the liquid film Lf formed in the through hole 11h is formed so that its front and back surfaces are approximately flat relative to the surface of the through hole region, so that the length of the liquid film Lf can be made approximately the same as the distance along the line in the penetrating axis direction of the through hole 11h (i.e., the thickness of the penetrating region of the substrate 10a).

Therefore, if liquid L is supplied dropwise to the liquid supply section 12 of the main body section 10 of the structure 1, the liquid L can be spread into the multiple through-holes 11h while automatically moving through the voids 10h formed inside the substrate 10a of the main body section 10 by capillary action, and a homogeneous liquid film Lf can be formed in each through-hole 11h. In other words, multiple liquid films Lf having a homogeneous film thickness can be formed in the through-hole region section 11 of the main body section 10.

(Spraying method)
Next, in a state where the liquid film Lf is formed in the plurality of through holes 11h in the through hole region 11 of the main body 10, air is blown from one surface of the through hole region 11 toward the other surface of the through hole region 11. Then, the liquid film Lf formed in the through holes 11h is blown away from the through holes 11h by the wind pressure of the air, and is blown out (i.e., sprayed) in the traveling direction of the air as fine droplets from the openings of the through holes 11h formed on the opposite surface.
Since the size of these fine droplets tends to depend on the size of the through-holes 11h, it is possible to adjust the size of the droplets by adjusting the size of the through-holes 11h.

The present invention will be described below based on examples, but the present invention is not limited to these examples.

[Experiment 1: Experiment using the structure of the present invention as a filter]
In recent years, the social need for rapid diagnosis of diseases, which has also become an issue with coronavirus infections, is ever-increasing. In addition to clinical testing, in the event of sudden environmental contamination or food poisoning, on-site analysis is necessary to identify the cause and minimize damage, and there is a need to further promote the development of small biochips and small analytical devices that can perform analysis quickly and easily on-site. These samples contain many contaminants (particles and aggregates) other than the target of analysis, which have a negative effect on the analysis, so the contaminants are filtered out.
In general filtration, particles and other impurities are filtered out according to the pore size of the fibers of filter paper or filters. Usually, the test liquid is allowed to flow naturally by gravity, and pressure reduction and pressurization are required with pumps or syringes to improve filtration efficiency. However, there are issues with the applicability of existing filtration devices to small analytical chips, such as low filtration efficiency under natural flow, the need for a large filtration area, and the high cost and low portability of pumps and syringe pumps. Therefore, there is a demand for the development of small filtration devices suitable for on-site analysis. Furthermore, with samples containing a very high solid content such as blood, feces, and industrial wastewater, there is a problem of reduced filtration efficiency due to clogging of the filter substrate used for filtration.

In order to solve the above problems, with the aim of developing a small and simple filtration device suitable for rapid diagnosis and on-site analysis, a substrate was produced in which a sheet-formed fiber layer is used as a filtration substrate, a sample is spread on the fiber layer by capillary action without using a pump or the like (pumpless), and the filtered sample liquid can then be collected from a perforation (corresponding to the through-hole in this embodiment) provided at the end of the chip.
The holes used for sampling are several hundred μm to several mm in size (i.e. through holes that penetrate the front and back of the filtration substrate), and the filtrate that spreads the fiber layer forms a liquid film due to surface tension. By inserting a sample collection tip into the liquid film and applying a slight reduced pressure with a pipette, etc., it is possible to aspirate and collect the filtrate.

The filtration substrate was prepared by mixing PET fine fibers (fiber width: 1.0 dtex, fiber length: 0.2 mm) with a binder, coating the mixture on waterproof paper (waterproof paper: LBP-WPF22MDP, Sanwa Supply, paper thickness 220 μm, A4 size) and drying. Typical conditions are 90% PET fiber and 10% binder.
The conditions for preparing the raw materials are as follows:
1) Add the PET fiber to the binder and mix by hand, stirring thoroughly. 2) Mix further and degas using a centrifugal mixer [Thinky Corporation: Awatori Rentaro ARE-310].

The filtration base material was applied onto the waterproof paper using an applicator [PI1210@Tester Sangyo]. The coating speed was 20 mm/s. The applicator clearance was adjusted according to the final coating thickness.
The coated paper was sandwiched between iron frames for drying to prevent curling, and was promptly dried in a hot air dryer [OFW-60SB-R@ETTAS] under the following drying conditions (hot air drying at 60°C for 25 min, hot air drying at 80°C for 15 min, hot air drying at 150°C for 30 min).

In order to make chips from the prepared filtration substrate, laser processing (Universal Systems, ILS9.75, maximum laser output 40W, maximum plotter speed 3500mm s ^-1 ) was performed to a specified shape. In the laser processing, the periphery was perforated into a rectangle (rather than cutting completely, the uncut portion was left in a small area around the periphery so that the chips were held on the large substrate). The laser processing conditions were laser output 20%, speed 8%, and drive pulse rate PPI = 1000. The size of a typical filtration chip piece was 5 mm in the short side direction and 13 mm in the long side direction (Figure 12).
Next, a guide hole (about 0.5 mm) toward the drill hole of the sample collection part was made by laser processing. After that, a drill "M655D, Makita Corporation, drill diameter 1 mm" was used to process a hole in the guide hole. A tape (mending tape, 3M Japan Co., Ltd.) was attached to the surface (attachment position: 5 mm width at the center of the substrate) as a mechanism to prevent the unfiltered sample from sliding upward during filtration (to prevent the unfiltered sample from flowing along the substrate surface and reaching the perforation). In addition, a mending tape was also attached to the waterproof paper side of the perforated portion to prevent the sample from leaking from the back surface of the substrate and to prevent air bubbles from being mixed in when the sample is collected from the perforation. A completed diagram of the biochip is shown in FIG. 12.
A photograph of the drilled holes is shown in Figure 13. The drill hole diameter (the diameter of the part where the surface fibers were scraped off in Figure 12) was 1000.2 ± 159.0 µm in the long side direction and 986.1 ± 14.5 µm in the short side direction (n = 5).

The progress of filtration of the artificial blood sample is shown in FIG.
The specimen rapidly spread out in a thin sheet shape, and the filtered clean specimen penetrated the other end and reached the perforations.
The state of sample collection using a pipette tip is shown in Figure 15. A liquid film was generated in the perforation due to surface tension, and the liquid film sample filtered out from the perforation could be collected using a pipette tip or the like. Filtration proceeds automatically due to capillary action, and does not require auxiliary mechanisms for filtration such as conventional pumps or pressure application.
A sample [mock blood: Yamashina Seiki Co., Ltd., PB-10R mixed with copper phthalocyanine aqueous solution (40 mM) at a ratio of 99:1] was dropped onto the sample drop position of the substrate, and it was investigated whether the sample was immersed while being filtered within the biochip. 180 seconds after dropping, the sample collection volume of a 10 μL micropipette (Micropipette Research Plus V 0.5-10 μL) was set to 10 μL, and the tip of the pipette tip (with the pipette push button pushed to the first stop) was inserted into the hole. The push button was slowly (over 20 seconds) released to suck up the filtered plasma sample.
The results of this experiment are shown in Table 1. As the ink film thickness increases, the amount of ink taken from the substrate also increases.

In the substrate with a filtration substrate thickness of 220.8 and 329.2 μm, 5 mg or more of sample could be collected from the perforation. This 5 mg or more of sample collection was possible as a filtrate amount calculated from the theoretical volume of the perforation (when the perforation diameter is 1 mm and the membrane thickness is 300 μm, the theoretical volume of the void is 0.23 μL, and when the specific gravity of water is 1 gmL ⁻¹ , it is 0.23 mg). This suggests that the filtrate present in the substrate around the perforation can be sucked from the perforation under reduced pressure. The filtrate is widely spread in the filtration substrate by capillary action and is gently held in the connected void layer inside the substrate, and it is considered that the filtrate can be sucked with little pressure loss even with a weak reduced pressure from the tip of the tip.

[Experiment 2: Experiment using the structure of the present invention as a liquid spraying tool]
Liquid spraying is a core technology widely used in the industrial field for coating, printing, inspection, mixing, etc. Known devices for liquid spraying to date include ultrasonic application, two-fluid nozzles, cross-flow nebulizers, pneumatic (coaxial) nebulizers, grid nebulizers, etc. However, all of these devices require precise machining of the spray part, pressure-resistant parts, and separate liquid delivery pumps, gas flow paths, and ultrasonic generators, leaving room for improvement in portability and cost.

To solve the above problems, we have created a device that uses a flow path made of fibers such as paper to deliver a sample based on capillary action, and can spray minute droplets by sending an airflow to a liquid film formed in a perforation prepared at the end of the flow path. Because capillary action occurs due to voids contained in the substrate, liquid can be delivered to the appropriate location without using a pump. Furthermore, we thought it would be possible to generate minute droplets by processing minute perforations (corresponding to the through holes in this embodiment) at the end of the flow path, forming a liquid film in the perforation based on surface tension, and then applying air pressure to the liquid film.

A filter paper laminate sheet was prepared as the base for the spray substrate. The filter paper laminate sheet was prepared by laminating filter paper (chromatographic filter paper, No. 590) onto a polystyrene waterproof substrate (precut backing sheet, GL-187, manufactured by Lohmann). The backing sheet was pre-coated with an adhesive, and after laminating the filter paper, it was pressed (press pressure: 0.3 kg cm ^-2 ) to ensure that the waterproof substrate and filter paper were firmly attached to each other.

The prepared sheet was processed with perforations for forming a liquid film (i.e., through holes penetrating the front and back of the spray substrate). Universal Systems' ILS9.75 was used for laser processing (maximum laser output 40W, maximum plotter speed 3500mms ^-1 ). The laser processing conditions were as follows: laser output 10%, speed 5%, drive pulse rate PPI = 40. The laser was irradiated from the backing sheet side. At a laser output of 15%, the hole diameter was 331.8 μm on the backing sheet side, 116.3 μm (N = 6) on the filter paper side, and the hole density was 7.0 pieces / ^mm2 . The perforations were made with a width of 4 mm in the long side direction, with the upper end being 0.5 mm from the tip of the filter paper laminated sheet.

The spray substrate prepared under the substrate preparation conditions was cut into 5 (horizontal) x 40 (vertical) mm using a cutter. A small amount (0.3 mL) of colored water solvent (sample of copper phthalocyanine tetrasulfonic acid sodium dissolved in pure water, concentration 10 mmol dm ^-3 ) was added to a small glass container (volume 2 mL), and the spray substrate with perforations was placed vertically in the container. The spray substrate was immersed under conditions where the bottom of the spray substrate was in contact with the coloring liquid by about 2 mm. Wind pressure from an air sprayer (air duster, AD400FL, Orientec Co., Ltd., set air pressure (about 50 kPa)) was applied to the perforations.

As shown in Figure 16, the sample liquid penetrated the filter paper of the spray base material to the tip without using a pump or the like. This is thought to be due to the capillary phenomenon caused by the gaps in the filter paper. The perforations in the spray base material were colored, suggesting that the perforations were filled with liquid.
The results of optical microscope observation of the perforations in the sprayed substrate during liquid advancement are shown in Figure 17. The inside of the perforations is colored, and it is believed that a liquid film is formed in the micropores of several hundred μm by the surface tension of the liquid. Next, air was sprayed into the perforations, and droplets were sprayed from the surface of the holes (Figure 18). White paper was placed on the outlet side of the perforations to trap the sprayed droplets. A photograph of the paper surface after the droplets were trapped is shown in Figure 19.
It was clear from Figure 19 that droplets with diameters ranging from several hundred μm to several mm collided with the white paper at the exit of the perforation. The diameter of the droplets adhering to the surface of the filter paper was measured from an optical microscope image and found to be 308±81 μm (n=20). It is believed that the droplets were ejected from the exit side when the liquid film was blown off the inner wall of the perforation by wind pressure.

The structure of the present invention is suitable as a tool for use in fields such as medicine, biochemistry, pharmacology, chemistry, the environment, food, and industry.

REFERENCE SIGNS LIST 1 Structure 10 Main body 10a Substrate 10b Water-permeable material 10c Water-impermeable material 10d Nanofiber layer 10h Void in substrate 11 Through-hole region 11h Through-hole 12 Liquid supply section Lf Liquid film formed in through-hole

Claims (15)

A main body includes a through hole region having through holes provided on a substrate and penetrating the substrate from front to back, and a liquid supply portion continuous with the through hole region provided on the substrate ,
The base material of the main body portion is
a plurality of voids are formed in the base material, the voids communicate between the liquid supply portion and the through-hole , and through which liquid can pass by capillary action;
The through hole is
A structure formed to a size capable of holding a liquid by surface tension. The main body portion is
The substrate is
2. The structure according to claim 1, further comprising a plurality of water-permeable materials through which liquid can pass by capillary action. The main body portion is
The substrate is
The device includes a plurality of water-permeable materials through which liquid can pass by capillary action, and a plurality of water-impermeable materials disposed between the water-permeable materials,
The void is
2. The structure of claim 1, which is formed from said water-permeable material and said water-impermeable material. The main body portion is
The substrate is
The present invention comprises a plurality of nanofiber layers made of nanofibers, and a water-impermeable material disposed between the plurality of nanofiber layers,
The void is
The structure of claim 1 , which is formed by the nanofiber layer and the water-impermeable material. The base material of the main body portion is
The structure according to claim 4, wherein the nanofiber layer located on the surface of the substrate has holes penetrating the nanofiber layer. The main body portion is
6. The structure according to claim 1, wherein the base material has a shape-retaining layer on a back surface side thereof for retaining a shape. The main body portion includes:
7. The structure according to claim 1, further comprising a liquid diffusion preventing member provided on the side of the liquid supply section facing the through hole region. The main body portion includes:
8. The structure according to claim 1, wherein a cover member is provided on one or the other surface of the through hole region. The cover member has:
9. The structure according to claim 8, wherein holes are formed in the through-hole region at locations where the through-holes are located. 10. The structure according to claim 1, wherein the through-hole has an opening diameter of 50 μm to 2000 μm. 3. The structure according to claim 2, wherein the substrate is filter paper. A filtration method using a filtration device used for filtering a liquid, comprising the steps of:
The filtering device is
a main body having a through hole region having through holes penetrating the front and back of a substrate, and a liquid supply portion continuous with the through hole region, the main body having a plurality of voids in the substrate that communicate with the through holes and through which liquid can pass by capillary action, the through holes being a structure formed to have a size capable of holding liquid by surface tension ,
A liquid filtering method comprising: supplying a liquid to a liquid supply portion of the structure; and sucking a liquid film formed in the through-holes of the structure. 13. The method for filtering a liquid according to claim 12, wherein the liquid is a body fluid. 14. The method for filtering a liquid according to claim 13, wherein the liquid is blood. A method for spraying a liquid using a liquid spray device, comprising:
The liquid spray device is
a main body having a through hole region having through holes penetrating the front and back of a substrate, and a liquid supply portion continuous with the through hole region, the main body having a plurality of voids in the substrate that communicate with the through holes and through which liquid can pass by capillary action, the through holes being a structure formed to have a size capable of holding liquid by surface tension ,
A liquid spraying method comprising: supplying liquid to a liquid supply portion of the structure; and blowing air against a liquid film formed in a through hole of the structure.

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