WO2019059265A1

WO2019059265A1 - Method for manufacture of microneedle and microneedle

Info

Publication number: WO2019059265A1
Application number: PCT/JP2018/034766
Authority: WO
Inventors: 邦男宮地; 及川　陽一; 耕平豊田
Original assignee: シンクランド株式会社
Priority date: 2017-09-20
Filing date: 2018-09-20
Publication date: 2019-03-28
Also published as: JPWO2019059265A1

Abstract

[Problem] To enable filling of a hollow microneedle with a fill liquid through a simple method and easy manufacturing of a microneedle having a hollow needle filled with a fill liquid. [Solution] According to this method for microneedle manufacture, multiple tapered-cone needles 3 are formed on a sheetlike microneedle 1, a through-hole 4 is formed at either the apex 3A or the vicinity of the apex 3A of each tapered-cone needle and penetrates to the reverse face 2B of the sheet, the ends of the through-holes on the sheetlike microneedle 1 are brought into contact with a fill liquid 9, and the through-holes are filled with the fill liquid through capillary action.

Description

Microneedle manufacturing method and microneedle

The present invention is suitable, for example, for a method of manufacturing a hollow type microneedle using a bioabsorbable polymer material or a metal / ceramic material.

In recent years, microneedles using polymer compounds such as bioabsorbable polymers are widely known for cosmetic purposes and the like. (See, for example, Patent Document 1).

Patent No. 5495034

However, since the microneedles described above microneedle the target substances as they are, hollow microneedles are required because the usable target substances are limited.

The present invention has been made to solve such problems, and its object is to provide a method of manufacturing a hollow type microneedle and a microneedle.

In order to solve such problems, in the method of manufacturing a microneedle according to the present invention, a sheet shape is formed in which a plurality of needle piles are formed, and a through hole penetrating from the vertex or apex vicinity of each needle pile to the back of the sheet is formed. The through hole end of the microneedle is brought into contact with the filling liquid, and the through hole is filled with the filling liquid by capillary action.

Moreover, the microneedle of the present invention is
A plurality of needle piles are formed, and a through hole penetrating from the vertex or apex vicinity of each needle pile to the back surface of the sheet is formed, and the through hole is filled with the filling liquid,
h = height of through hole, T = surface tension (N / m), θ = contact angle between filling solution and inner surface of through hole (°), = = density of filling solution (kg / m 3), g = gravitational acceleration (Height of square of 9.80665 m / s), r = inner diameter of tube (radius: mm), height h of capillary phenomenon expressed as equation (1) is 70% of height Hh of the through hole More than

It is characterized by

The present invention can realize a microneedle manufacturing method and a microneedle capable of easily manufacturing a hollow type microneedle.

It is the schematic which shows the structure of a microneedle. It is the schematic where it uses for description of the manufacturing method (1) of a microneedle. It is the schematic where it uses for description of the manufacturing method (2) of a microneedle. It is the schematic where it uses for description of the manufacturing method (3) of a microneedle. It is the schematic where it uses for description of the manufacturing method (4) of a microneedle. It is the schematic where it uses for description of the manufacturing method (5) of a microneedle. It is the schematic where it uses for description of the manufacturing method (6) of a microneedle. It is the schematic where it uses for description of the manufacturing method (7) of a microneedle. It is the schematic where it uses for description of the manufacturing method (8) of a microneedle. It is the schematic where it uses for description of the manufacturing method (9) of a microneedle. It is a schematic diagram by which it uses for description of filling of a filling liquid. It is a schematic diagram by which it uses for description of arrangement | positioning of a protective material. It is a schematic diagram by which it uses for description of arrangement | positioning of a protective material, and filling of a filling liquid. FIG. 5 is a schematic diagram for describing the filling of the filling liquid from the back side of the sheet. It is a basic diagram which shows the structure of the through-hole provided in the side of a needle track.

First Embodiment
Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In recent years, in cosmetic and medical applications, microneedles consisting of microprojections with a small diameter have been proposed for the purpose of injecting a cosmetic component or drug as a target substance into the skin so as not to damage the skin as much as possible (for example, patent 5495034)). The microneedles are formed by transferring a pattern using a mold such as a mold.

In this microneedle, the microneedle itself contains the target substance, and the microneedle stuck in the skin is absorbed into the body as it is. However, there are limitations on the types and amounts of target substances that can be contained in the microneedles. For example, it is difficult to use a liquid or semi-solid substance at normal temperature.

However, since the microneedles have a fine structure, it is not easy to fill the holes with the filling liquid even if the holes are formed.

The inventors of the present invention have found a method of manufacturing a microneedle in which a hole is formed in the microneedle and a target substance is injected into the body through the hole.

As shown in FIG. 1 (A), in the microneedle 1 of the present invention, a plurality of needle ridges 3 projecting from the sheet surface 2A which is the surface side of the base sheet 2 are formed. FIG. 1B shows a cross-sectional view of the microneedle 1. Each needle thread 3 is formed with a through hole 4 penetrating from the vicinity of the vertex 3A or the vertex 3A to the back surface 2B.

The thickness of the substrate sheet 2 is not particularly limited, but is preferably 10 μm or more and 300 μm or less. When the base sheet 2 is too thin, it is difficult to obtain sufficient rigidity physically, and when it is too thick, the through hole height Hh which is the height of the through hole 4 becomes too large.

It is preferable that the needle height Hn from the sheet surface 2A to the apex 3A is about 30 to 500 μm. If it is smaller than 30 μm, the apex 3A of the needle peak 3 can not reach the skin to a sufficient depth, and if it is 500 μm or more, it is difficult to obtain sufficient structural strength.

The radius of the through hole 4 is not particularly limited, but is preferably 1 μm or more and 30 μm or less. If the radius is too small, the volume that can be filled in the through hole 4 becomes too small, and if the radius is too large, the physical strength required as the needle crest 3 can not be maintained, which is not preferable.

The material of the base sheet 2 and the needle pile 3 is not particularly limited, but for example, various inorganic materials such as metals such as aluminum and stainless alloys, silicon, carbon, ceramics, various mineral materials including calcium based minerals, and organic materials A high molecular compound etc. can be used suitably as a main component. In particular, when used for medical and cosmetic applications, it is preferable to use, as the material of the base sheet 2, a bioabsorbable material which is harmless to the human body and which is absorbed by adjustment.

In the present specification, the polymer compound means an organic compound having a weight average molecular weight Mw of 5000 or more. The main component means that the polymer compound is 50% by weight or more of the whole workpiece. As a high molecular compound, it is preferable that Tg (glass transition point) is 50 degreeC or more, More preferably, it is 70 degreeC or more. If the Tg is low, handling at normal temperature becomes difficult.

As a high molecular compound, only 1 type may be contained and 2 or more types may be mixed. In addition, the ratio of this main component is the weight after the completion of the whole processing process of a to-be-processed object, and does not contain what is called a solvent component which evaporates intentionally at the drying process after formation of microprotrusion. That is, it is the ratio after the end of processing of the workpiece.

As the polymer compound, known compounds (synthetic polymers and natural polymers) can be used. For example, in addition to various plastic materials such as PET (polyethylene terephthalate), polyethylene, polypropylene, acrylic resin, epoxy resin, polystyrene, etc., bioabsorbable polymers can be used.

Known compounds (synthetic polymers and natural polymers) can be used as bioabsorbable polymers. For example, ester compounds such as polylactic acid, polyglycolic acid, poly-ε caprolactone, poly-rho-dioxane, polymalic acid, acid anhydrides such as polyacid anhydride, ortho ester compounds such as polyorthoester, carbonates such as polycarbonate Compounds, phosphazene compounds such as polydiaminophosphazenes, peptide compounds such as synthetic polypeptides, phosphate ester compounds such as polyphosphoester urethanes, carbon-carbon compounds such as polycyanoacrylates, poly-β-hydroxybutyric acid, polymalic acid, etc. Ester compounds, polyamino acids, chitin, chitosan, hyaluronic acid, sodium hyaluronate, pectic acid, galactan, starch, dextran, dextrin, alginic acid, sodium alginate, cellulose compounds Cellulose, Carboxymethylcellulose, Hydroxyethylcellulose, Hydroxypropylcellulose, Hydroxypropylcellulose, Methylcellulose), Gelatin, Agar, Celtrol, Leozan, Glycanth, Pullulan, Glycoside Compounds such as Gum arabic (Polysaccharides), Collagen, Gelatin, Fibrin, Gluten And peptide compounds (peptides, proteins) such as serum albumin; phosphate ester compounds (nucleic acids) such as deoxyribonucleic acid and ribonucleic acid; and vinyl compounds such as polyvinyl alcohol.

The same material may be used as the material of the base sheet 2 and the needle pile 3, and different materials may be used. The same material is used when forming the needle pile 3 by scraping the base sheet 2 or the like, and when forming the needle pile 3 by molding or the like on the base sheet 2, another material or the same material is used. The material is appropriately selected.

For example, as shown in FIG. 2, in the microneedle 1, the through hole 4 is formed after the needle peak 3 is formed on the base sheet 2. As a method of forming the needle head 3, various methods such as irradiation of a circularly polarized light vortex laser beam to the substrate sheet 2, molding, etching, ion milling and the like can be used. After the needle piles 3 are formed, the through holes 4 are formed by, for example, a method such as laser irradiation or fine hole processing using a micro drill.

In addition, the needle head 3 and the through hole 4 can be simultaneously formed. For example, as shown in FIG. 3, a mold 11 having a microneedle transfer pattern, a rod member 15 and a spacer 19 are used. The mold 11 has a protrusion concave portion 12 which is a transfer pattern of a microneedle, and a through hole 4 which leads to the protrusion concave portion 12 and leads to the bottom surface of the mold 11 (opposite surface of the protrusion concave portion 12). . The through holes 4 are provided one by one for all the projection recesses 12.

The rod-like member 15 has a plurality of rod portions 16 formed in accordance with the position of the through holes 4 and a flat plate portion 17, and is fixed so that the rod portions 16 project from the plate portion 17. ing. The spacer 19 exists in a free state that can be removed from the rod-like member 15 and the mold 11.

As shown in FIG. 3, first, the rod-shaped member 15 is inserted into the mold 11, and the spacer 19 is sandwiched between the rod-shaped member 15 and the mold 11. As a result, the rod-shaped member 15 penetrates the through hole 4 of the mold 11 and protrudes from the mold 11 while leaving a certain gap space between the rod-shaped member 15 and the mold 11.

As shown in FIG. 4, the base sheet 2 is filled into the mold 11 in which the rod-like member 15 is inserted. There is no particular limitation on the method of solidification in which the substrate sheet 2 is filled in a liquid or semi-liquid state, and the substrate sheet 2 which has been heated and liquefied is cooled, and the low molecular weight substrate sheet 2 is used. The base sheet 2 is solidified by curing, crystallization, evaporation of solvent components and the like caused by a chemical reaction (polymerization) with a crosslinking agent and a curing agent.

After solidification, the substrate sheet 2 is released from the mold 11 and becomes a molded article. Here, if it is attempted to release the substrate sheet 2 while the rod-like member 15 is inserted, the substrate sheet 2 may be deformed or the rod portion 16 may be broken, so the rod-like member 15 is pulled out. Then, the substrate sheet 2 is released. As shown in FIGS. 5A and 5B, the spacer 19 is removed first, and the rod-shaped member 15 is moved to the mold 11 side, and then the rod-shaped member 15 is pulled out from the mold 11. Then, as shown in FIG. 6, the microneedle 1 can be manufactured by releasing the base sheet 2 from the mold 11.

Further, as shown in FIG. 7, the through

holes

112 and 114 are respectively formed in the plate-

like pedestal plates

111 and 113. The

base plates

111 and 113 constitute the base sheet 2 in the microneedle 1 as a molded product, and the material thereof is not limited.

Then, as shown in FIG. 8, the rod portion 116 of the rod-like member 115 is penetrated so as to pierce the workpiece 120, and as shown in FIG. 9, the base plate 103 is slowly pulled up (or the base plate 101 is pulled down). The upper and lower (root) portions in the vicinity of the

pedestal plates

111 and 113 become thicker, while the vicinity of the center becomes thinner. In this state, the workpiece 110 is solidified, and after pulling out the rod-like member 105, the microneedle 1 can be manufactured as shown in FIG. Alternatively, the rod member 105 can be pulled out after the base plate 103 is pulled up to solidify the workpiece until the central portion is broken.

In the present invention, as shown in FIG. 11, the filling liquid tank 8 holding the

end

4A or 4B of the through hole 4 of the sheet-like microneedle 1 is brought into contact, and the filling liquid 9 is filled in the through hole 4 by capillary action. To fill.

The height at which capillary action occurs is represented by equation (1).

Where h = height of capillary action, T = surface tension (N / m), θ = contact angle between filling liquid and inner surface of through hole (°), = = density of filling liquid (kg / m 3), g = Gravity acceleration (9.80665 m / s squared), r = inside diameter of tube (radius: mm)

Therefore, in the case where the height h of the through hole Hh ≦ the capillary action h, the through hole 4 is filled with the filling liquid 9 at a filling rate of approximately 100%. Although the filling rate is not necessarily 100%, it is preferable that a large amount of filling liquid 9 which is the target substance be filled. In addition, if the filling rate is low, the position of the filling liquid 9 is biased to form a cavity, which may make it difficult for the filling liquid 9 to be taken into the body from the skin. Therefore, it is preferable that the through hole height Hh ≦ the height h × 70% of the capillary phenomenon.

The through hole height Hh is preferably 50 μm or more and less than 1000 μm. If the through hole height Hh is too small, the distance from the skin surface reached by the tip of the needle pile 3 is not sufficient. If the through hole height Hh is too large, the strength of the needle pile 3 may be insufficient.

In addition, the filling liquid 9 (target substance) is not particularly limited, but is a liquid, a drug obtained by liquefying a pharmaceutically active ingredient used as various medicines such as insulin, hormone agent, antibody, vaccine, collagen, hyaluronic acid Cosmetic solutions obtained by liquefying various cosmetic components such as, and nutrient solutions obtained by liquefying various nutritional components such as glucose and vitamins are preferably used.

The viscosity (25 ° C., 60 rpm, L-type viscometer) of the filling liquid 9 is preferably 0.5 mPa · s or more and 500 mPa · s or less, more preferably 0.8 mPa · s or more and 200 mPa · s or less. If the viscosity is too low, the stability of the filling liquid 9 against impact or the like will decrease, and if the viscosity is too high, it is not preferable because the capillary phenomenon hardly occurs.

Then, as shown in FIG. 12, the microneedle 1 filled with the filling liquid 9 is placed on the protective material 50 in a state in which the upper and lower ends of the through hole 4 are open. The protective material 50 has a support portion 51 for supporting the flat portion 2 </ b> C where the needle peak 3 is not formed in the base sheet 2, and a bottom surface 52. The support portion 51 is in contact with the flat portion 2C, and the depth D of the support portion 51 is formed higher than the height Hn of the needle head 3, and prevents any contact with the apex of the through hole 4. Thereby, it can prevent that the filling liquid 9 in the through-hole 4 leaks outside.

The top surface 52 is not necessarily required, and part or all of the bottom surface 52 may be open. There is no restriction in the vertical direction in the microneedle 1 and the protective material 50, and the vertical direction may be reversed (in this case, the bottom surface 52 is the top surface).

Further, by forming the through hole 4 offset (shifted) from the vertex of the needle peak 3 (see FIG. 10), the height of the needle peak 3 can be maintained, and the tip of the through hole 4 in the needle peak 3 to the vertex It is possible that the area serves to protect the through hole 4. Furthermore, although not shown, it may be offset from the top of the needle head 3 and inclined in the opposite direction to the offset direction of the through hole 4. Thereby, the volume inside the through hole 4 can be increased by the amount of inclination, and the physical strength of the needle peak 3 can be maintained by increasing the distance from the surface of the needle peak 3 to the through hole 4 as much as possible.

The microneedle 1 thus formed is used by piercing the apex 3A on the skin. When the microneedle 1 is pierced by the skin, the filling liquid 9 inside the through hole 4 comes in contact with the body fluid, so it is pulled by the body fluid by surface tension and absorbed into the body. In the case where a bioabsorbable polymer is used as the material of the needle pile 3, the needle pile 3 itself can be absorbed into the body by leaving the microneedle 1 stuck to the skin as it is.

In addition, a through-hole with a diameter of 20 μm is formed in a 300 μm-thick flat plate made of sodium hyaluronate (hyaluronic acid 85 wt%, water 15 wt%), and red dye solution (water 0.5 ml with 0.015 g When dissolved and diluted with 5 ml of ethanol was brought into contact with one side of a flat plate, the red dye solution was filled in the through hole and it was confirmed by experiment that the filled state is maintained as it is .

<Operation and effect>
Hereinafter, the features of the invention group extracted from the above-described embodiment will be described by showing problems, effects, and the like as necessary. In the following, for ease of understanding, the corresponding configurations in the above-described embodiments are appropriately shown in parentheses, but the present invention is not limited to the specific configurations shown in parentheses. In addition, the meanings and examples of the terms described in the respective features may be applied as the meanings and examples of the terms described in the other features described in the same word.

In the method of manufacturing a microneedle according to the present invention, a plurality of needle piles (needle piles 3) are formed, and they are penetrated from the sheet surface (sheet front surface 2A) side where the needle piles are formed to the sheet back surface (sheet back surface 2B) side The end of the through hole of the sheet-like microneedle (microneedle 1) in which the through hole (through hole 4) is formed is brought into contact with the filling liquid (filling liquid 9), and the through hole is filled with the filling liquid Do. In addition, the sheet | seat surface side means all the surfaces which united the needle-peak part and the plane part in which the needle-peak is not formed.

Thereby, the filling liquid can be filled by a simple method, and the manufacture of the microneedle can be simplified.

h = height of capillary action, T = surface tension (N / m), θ = contact angle between filling liquid and inner surface of through hole (°), ρ = density of filling liquid (kg / m 3), g = gravitational acceleration (Height of square of 9.80665 m / s), r = inner diameter of tube (radius: mm), the height h of the capillary phenomenon expressed as the equation (1) is 70% or more of the through hole height Hh is there

As a result, the filling rate of the filling liquid to be filled in the through hole 4 can be increased, and the void (air content) rate in the through hole 4 can be reduced to improve the continuity. When put in, the filling liquid can be injected smoothly without stopping by air.

By contacting the top side of the needle pile with the filling liquid, the portion contacting the filling liquid is reduced compared to the method in which the back side of the sheet is in contact with the filling liquid, and excess filling liquid is deposited It is not necessary.

The microneedle is characterized in that the through hole is formed by using a laser which is irradiated from the tip direction of the needle pile to the needle pile. As a result, the through hole can be formed easily and quickly with an arbitrary diameter, and the component melted by the laser is attached to the periphery of the through hole to form a bulge, and the bulge makes contact with the outside. Since it can prevent, it can play a role which protects the filling liquid inside a through-hole.

The microneedle is characterized in that the through hole is formed by pulling out a rod-like member which has been penetrated in advance when forming the needle peak, and the rod-like member is drawn in the direction of the root of the needle peak. As a result, the root portion is swelled, and contact with the outside can be prevented by the swell, which can play a role of protecting the filling liquid in the through hole.

By forming the through holes at positions offset from the apexes by a predetermined offset amount, the apexes can play a role in protecting the through holes. Although the amount of offset is not limited, the strength in the vicinity of the tip of the needle peak can be maintained by securing the offset amount of 1⁄4 or more of the radius of the needle tip. Also, by setting the radius of the needle to less than 2.0 times, more preferably less than 1.5 times, it is possible to reliably introduce the filling solution into the skin. The offset amount is a plane distance (a distance parallel to a plane portion of the sheet surface) from the needle peak to the center of the through hole. Further, the radius of the needle peak is the distance from the intersection of the ridge line along the slope portion from the needle peak and the plane line extending the plane of the sheet surface to the needle peak. If the needle peak is not at the perfect center position of the needle peak, the average value is regarded as the radius.

When the height h of the through hole is 50 μm or more and less than 1000 μm, a microneedle suitable for injection into the skin can be provided.

When the viscosity of the filling liquid is 0.5 mPa · s or more and 500 mPa · s or less, the filling liquid can be stably held inside the through hole while causing capillary phenomenon.

The through hole is formed in the vicinity of the root portion of the needle peak. As a result, since it is sufficient to provide the through hole in the flat portion where the needle pile is not formed, the strength of the needle pile can be maintained.

Protective material (protective material) having a facing surface facing the sheet and a supporting portion (supporting portion 51) which is formed to protrude from the facing surface and is formed to be higher than the needle peak height from the sheet surface to the top of the needle peak 50),
It arrange | positions so that the vertex of the said support part and the flat part in which the said needle | hook in the said sheet | seat may not be formed may contact.

Thereby, the microneedle can be appropriately protected so that the tip of the through hole does not contact.

The two ends of the through hole are open, which can simplify the manufacturing process.

In addition, the microneedle pierces the skin at the top of the needle peak and contacts the body fluid inside the skin, thereby using surface tension to absorb the filling fluid into the body. Thus, the microneedle can absorb the target substance into the user's body in a simple procedure without requiring special pressurization or the like.

Furthermore, as shown in FIG. 13, it is also possible to fill the inside of the through hole 4 with the filling liquid 9 immediately before using the microneedle 2. In this case, the protective material 150 is provided with a hole 155 penetrating between the support portions 150 at or near the bottom portion of the support portion 151. When the user pours into the protective material 150 a filling solution 9 such as a cosmetic solution, a cosmetic solution, or a special solution which is separately attached to the protective material 150 or held by the user, the entire area of the protective material 150 is formed through the holes 155. The filling liquid 9 spreads to form the filling liquid tank 8.

The depth D of the support portion 151 in the protective material 150 is formed slightly larger than the height Hh of the needle head 3 (for example, 0.05 to 0.5 mm). Therefore, just by the user pouring the filling liquid 9 into the protective material 150 and mounting the microneedle 1, the apex 3A of the needle pile 3 is positioned without coming into contact with the bottom surface 152, and the user can easily fill the apex 3A with the filling liquid The filling liquid 9 can be filled in the through hole 4 of the microneedle 1 by contacting the tank 8.

That is, the depth D of the support portion 151 in the protective material 150 is formed to be slightly larger than the height Hh of the needle head 3, and a hole is provided in the hole or the support portion 151 so that the liquid can move between the support portions 151. As a result, the filling liquid 9 can be spread over the entire area of the protective material 151 to form the filling liquid tank 8, and the position of the apex 3A is positioned slightly above the bottom surface 152 by the support portion 151, and filling is performed by capillary action. The liquid 9 can be easily filled.

Further, as shown in FIG. 14, the filling liquid 9 can be sucked up from the back surface 2 B side of the microneedle 1. In this case, for example, a predetermined amount of filling liquid is dropped near the center of the flat tray 250, and this is used as the filling tank 8. Set the microneedle 1 so that the vicinity of the center makes contact with the filling tank 8 first while bending the microneedle 1, and make sure that the outer side gradually contacts the tray 250 while taking care not to enter air. 1 is placed on the tray 250. As a result, the filling tank 8 spreads over the entire area of the microneedle 1, and the inside of the through hole 4 can be filled with the filling liquid 9 by capillary action. In FIG. 14, although the outer frame 251 rising from the bottom surface 252 is formed on the tray 250 for the purpose of liquid leakage prevention, it is not necessarily essential. The tray 250 may be used as a protective material for protecting the tip 3A of the microneedle 1, and may be separately attached or sold separately.

Further, as shown in FIG. 15, the offset amount from the vicinity of the root portion of the needle head 2, that is, the offset from the tip of the needle head is larger than the radius of the needle head 2 and less than twice the radius of the needle head 2, more preferably 1.5 times You may provide the through-hole 4X so that it may set to less than. In other words, a through hole is formed immediately next to the needle pile. Even in this case, the filling liquid filled in the through hole 4X can be supplied where the skin is scratched by the needle head 2. Therefore, the same effect as in the case where the through hole is provided in the needle head Penetration) can be obtained. The through holes 4X can be formed before or after the formation of the needle pile, or simultaneously with the needle pile. When a needle pile is formed by molding, a through hole may be provided at a position where there is no needle pile in the mold, and the rod-like member may be penetrated.

Alternatively, the filling liquid 9 can be filled by dropping the filling liquid onto the back surface 2B of the microneedle 1 and spreading it using a spatula or the like.

The present invention can be applied to microneedles, for example in injection applications.

DESCRIPTION OF SYMBOLS 1: Microneedle 2: Base sheet 2A: Sheet surface 2B: Sheet back surface 2C: Flat part 3: Needle peak 3A: Vertex 4: Through hole 4A: End part 8: Filling liquid tank 9: Filling liquid

Claims

A plurality of needle peaks are formed, and the end of the through hole of the sheet-like microneedle in which the through hole penetrating from the sheet surface side to the sheet back side where the needle peaks are formed is formed is brought into contact with the filling liquid A method of manufacturing a microneedle, characterized in that the through hole is filled with a filling liquid by capillary action.
h = height of capillary action, T = surface tension (N / m), θ = contact angle between filling liquid and inner surface of through hole (°), ρ = density of filling liquid (kg / m 3), g = gravitational acceleration (Height of square of 9.80665 m / s), r = inner diameter of tube (radius: mm), height h of capillary phenomenon expressed as equation (1) is 70% of height Hh of the through hole More than

The method for producing a microneedle according to claim 1, characterized in that:
The method for manufacturing a microneedle according to any one of claims 1 and 2, wherein the top side of the needle crest is brought into contact with the filling solution.
The microneedle is
The method for manufacturing a microneedle according to any one of claims 1 to 3, wherein the through hole is formed with respect to the needle pile using a laser irradiated from the tip direction of the needle pile.
The microneedle is
At the time of needle formation, the through hole is formed by pulling out the rod-like member which has been penetrated in advance.
The method for manufacturing a microneedle according to any one of claims 1 to 3, wherein the rod-like member is pulled out in the direction of the root of the needle peak.
The through hole is
The method for manufacturing a microneedle according to any one of claims 1 to 5, wherein the microneedle is formed at a position shifted by a predetermined offset amount from the vicinity of the vertex.
The method for producing a microneedle according to any one of claims 1 to 6, wherein the height h of the through hole is 50 μm or more and less than 1000 μm.
The method for producing a microneedle according to any one of claims 1 to 7, wherein the viscosity of the filling liquid is 0.5 mPa · s or more and 500 mPa · s or less.
A protective material having a facing surface facing the sheet, and a supporting portion formed protruding from the facing surface and formed higher than the needle peak height from the sheet surface to the top of the needle peak,
The microneedle manufacturing method according to any one of claims 1 to 7, wherein the apex of the support portion is arranged to be in contact with the flat portion on which the needle crests are not formed in the sheet. .
The method for manufacturing a microneedle according to any one of claims 1 to 8, wherein two ends of the through hole are open.
The through hole is
The method for manufacturing a microneedle according to claim 1, wherein the microneedle is formed in the vicinity of a root portion of the needle peak.
A plurality of needle piles are formed, and a through hole penetrating from the vertex or apex vicinity of each needle pile to the back surface of the sheet is formed, and the through hole is filled with the filling liquid,
h = height of through hole, T = surface tension (N / m), θ = contact angle between filling solution and inner surface of through hole (°), = = density of filling solution (kg / m 3), g = gravitational acceleration (Height of square of 9.80665 m / s), r = inner diameter of tube (radius: mm), height h of capillary phenomenon expressed as equation (1) is 70% of height Hh of the through hole More than

A microneedle characterized by
The microneedle according to claim 11, characterized in that the filling liquid is absorbed into the body using surface tension by piercing the skin on the top side of the needle pile and contacting the body fluid inside the skin.
A plurality of needle piles are formed, and a through hole is formed from the apex of each needle pile or from the vicinity of the apex to the back surface of the sheet, and the through hole in the sheet-like microneedle filled with filling liquid in the through hole A method of using a microneedle characterized in that the tip portion is pierced in the skin and brought into contact with the body fluid inside the skin to absorb the filling liquid into the body using surface tension.