JPWO2019059265A1 - Microneedle sheet and method for manufacturing microneedle sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fill a hollow microneedle with a filling liquid by a simple method, and to easily produce a microneedle in which a hollow needle is filled with a filling liquid. In the method of manufacturing a microneedle according to the present invention, a plurality of needle peaks are formed, and a through hole is formed to penetrate from a vertex of a needle peak or a vicinity of the vertex to a sheet back surface. The end of the through hole of the sheet-like microneedle 1 is brought into contact with the filling liquid 9 and the filling liquid is filled into the through hole by capillary action. [Selection diagram] FIG.

Description

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

  BACKGROUND ART In recent years, microneedles using a polymer compound such as a bioabsorbable polymer have been widely known for cosmetic purposes and the like. (For example, refer to Patent Document 1).

Patent No. 5495034

  However, since the above-mentioned microneedles convert the target substance into microneedles as they are, there is a limit to the target substance that can be used, and thus a hollow-type microneedle is demanded.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a method of manufacturing a hollow-type microneedle and a microneedle.

  In order to solve such a problem, a method for manufacturing a microneedle according to the present invention is directed to a sheet-like method in which a plurality of needle ridges are formed, and a through-hole is formed to penetrate from the apex or near the apex of each needle ridge to the sheet back surface. The end of the through hole of the microneedle is brought into contact with the filling liquid, and the filling liquid is filled into the through hole by capillary action.

ことを特徴とする。Further, the microneedle of the present invention,
A plurality of needle ridges are formed, a through-hole penetrating from the top or near the top of each needle ridge to the sheet back surface is formed, and the filling liquid is filled in the through-hole,
h = height of through hole, T = surface tension (N / m), θ = contact angle between filling liquid and inner surface of through hole (°), ρ = density of filling liquid (kg / m3), g = gravitational acceleration (9.80665 m / s squared), and r = the inner diameter (radius: mm) of the pipe, the height h of the capillary phenomenon represented by the equation (1) is 70% of the height Hh of the through hole. Is over

It is characterized by that.

  ADVANTAGE OF THE INVENTION This invention can implement | achieve the manufacturing method of a microneedle which can manufacture a hollow type microneedle easily, and a microneedle.

It is the schematic which shows the structure of a microneedle. It is a schematic diagram with which explanation of manufacturing method (1) of a microneedle is offered. It is a schematic diagram with which explanation of manufacturing method (2) of a microneedle is offered. It is a schematic diagram offered for explanation of manufacturing method (3) of a microneedle. It is a schematic diagram offered for explanation of manufacturing method (4) of a microneedle. It is the schematic provided for description of the manufacturing method (5) of a microneedle. It is a schematic diagram offered for explanation of manufacturing method (6) of a microneedle. It is a schematic diagram offered for explanation of manufacturing method (7) of a microneedle. It is the schematic provided for description of the manufacturing method (8) of a microneedle. It is the schematic provided for description of the manufacturing method (9) of a microneedle. It is an approximate line figure used for explanation of filling of a filling liquid. It is an approximate line figure used for explanation of arrangement of a protection material. It is an approximate line figure used for explanation of arrangement of a protection material, and filling of a filling liquid. It is an approximate line figure used for explanation of filling of a filling liquid from a sheet back. It is an approximate line figure showing the composition of the penetration hole provided in the side of a needle mountain.

<First Embodiment>
Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  2. Description of the Related Art In recent years, microneedles having small projections with small diameters have been proposed for the purpose of injecting a cosmetic ingredient or a drug, which is a target substance, into skin so as not to damage the skin as much as possible in cosmetics and medical applications (for example, see Patents). No. 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 pierced into the skin is directly absorbed into the body. However, there are restrictions 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 inventor of the present application has found a method of manufacturing a microneedle in which a hole is formed in a microneedle and a target substance is injected into the body through the hole.

  As shown in FIG. 1A, the microneedle 1 of the present invention has a plurality of needle peaks 3 protruding from a sheet surface 2 </ b> A which is a surface side of the base sheet 2. FIG. 1B is a cross-sectional view of the microneedle 1. Each of the needle peaks 3 is formed with a through hole 4 penetrating from the vertex 3A or the vicinity of the vertex 3A to the seat back surface 2B.

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

  As the needle ridge, the needle ridge height Hn from the sheet surface 2A to the vertex 3A is preferably about 30 to 500 μm. If it is smaller than 30 μm, the vertex 3A of the needle peak 3 cannot reach a sufficient depth with respect to the skin, and if it is 500 μm or more, it becomes difficult to obtain sufficient structural strength, which is not preferable.

  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 capacity that can be filled in the through hole 4 becomes too small, and if the radius is too large, the physical strength required for the needle peak 3 cannot be maintained, which is not preferable.

  The material of the base sheet 2 and the needle ridge 3 is not particularly limited. For example, metals such as aluminum and stainless steel, various inorganic materials such as silicon, carbon, ceramic, and various mineral materials including calcium-based minerals, and organic materials A polymer compound or the like can be suitably used as a main component. In particular, when used for medical or cosmetic purposes, it is preferable to use a bioabsorbable material that is harmless to the human body and is absorbed by manipulative treatment.

  In this specification, a high molecular compound means an organic compound having a weight average molecular weight Mw of 5000 or more. The main component means that the polymer compound accounts for 50% by weight or more of the entire workpiece. The polymer compound preferably has a Tg (glass transition point) of 50 ° C. or higher, more preferably 70 ° C. or higher. If the Tg is low, it is difficult to handle at room temperature.

  As the polymer compound, only one kind may be contained, or two or more kinds may be mixed. The ratio of the main component is the weight of the workpiece after the completion of all the processing steps, and does not include a so-called solvent component that is intentionally evaporated in a drying step after the formation of the microprojections. That is, the ratio after the end of the processing of the workpiece.

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

  Known compounds (synthetic polymer and natural polymer) can be used as the bioabsorbable polymer. For example, ester compounds such as polylactic acid, polyglycolic acid, poly-εcaprolactone, poly-ρ-dioxane, polymalic acid, acid anhydrides such as polyanhydrides, orthoester compounds such as polyorthoesters, carbonates such as polycarbonate Compounds, phosphazene compounds such as polydiaminophosphazene, peptide compounds such as synthetic polypeptides, phosphate compounds such as polyphosphoester urethane, carbon-carbon compounds such as polycyanoacrylate, poly-β-hydroxybutyric acid, polymalic acid and the like Ester compounds, polyamino acids, chitin, chitosan, hyaluronic acid, sodium hyaluronate, pectic acid, galactan, starch, dextran, dextrin, alginic acid, sodium alginate, cellulose compounds (ethyl Cellulose, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, methylcellulose), gelatin, agar, celtrol, leozan, xanthan gum, pullulan, gum arabic and other glycoside compounds (polysaccharides), collagen, gelatin, fibrin, gluten And peptide compounds (peptides and proteins) such as serum albumin, phosphate compounds (nucleic acids) such as deoxyribonucleic acid and ribonucleic acid, and vinyl compounds such as polyvinyl alcohol.

  As the material of the base sheet 2 and the needle ridge 3, the same material may be used, or different materials may be used. When the needle ridge 3 is formed by shaving the base sheet 2, the same material is used. When the needle ridge 3 is formed on the base sheet 2 by molding or the like, another material or the same material is used. Materials are appropriately selected.

  In the microneedle 1, as shown in FIG. 2, for example, a needle ridge 3 is formed on a base sheet 2, and then a through hole 4 is formed. As the method of forming the needle peaks 3, various methods such as irradiation of the base sheet 2 with a circularly polarized light vortex laser beam, molding, etching, and ion milling can be used. After the needle peaks 3 are formed, the through holes 4 are formed by a technique such as laser irradiation or micro-hole processing by a micro drill.

  Further, the needle ridge 3 and the through hole 4 can be formed simultaneously. For example, as shown in FIG. 3, a mold 11 having a transfer pattern of microneedles, a bar-shaped member 15, and a spacer 19 are used. The mold 11 has a concave portion 12 for a projection which is a transfer pattern of a microneedle, and a through-hole 4 which penetrates through the concave portion 12 for the protrusion and passes through to the bottom surface of the mold 11 (the surface facing the concave portion 12 for a projection). . The through holes 4 are provided one by one for all the projection concave portions 12.

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

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

  As shown in FIG. 4, the base sheet 2 is filled in the mold 11 into which the rod-shaped member 15 has been inserted. The method of solidification in which the base sheet 2 is filled in a liquid or semi-liquid state is not particularly limited, and the base sheet 2 that has been heated and liquefied can be cooled or the low-molecular base sheet 2 can be used. The base sheet 2 is solidified by curing, crystallization, evaporation of a solvent component, and the like caused by a chemical reaction (polymerization) by a crosslinking agent or a curing agent.

  After solidification, the base sheet 2 is released from the mold 11 to form a molded product. Here, if it is attempted to release the base sheet 2 with the rod member 15 inserted, the base sheet 2 may be deformed or the rod portion 16 may be broken. Is released from the base sheet 2. As shown in FIGS. 5A and 5B, first, the spacer 19 is removed, the bar-shaped member 15 is once moved to the mold 11 side, and then the bar-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.

  As shown in FIG. 7, through holes 112 and 114 are formed in plate-shaped pedestal plates 111 and 113, respectively. The pedestal 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 bar portion 116 of the bar-shaped member 115 is penetrated so as to penetrate the workpiece 120, and as shown in FIG. 9, the pedestal plate 103 is slowly pulled up (or the pedestal plate 101 is lowered). The upper and lower (root) portions near the pedestal plates 111 and 113 become thicker, while the center portion becomes thinner. In this state, the workpiece 110 is solidified, the bar-shaped member 105 is pulled out, and then cut at the center, whereby the microneedle 1 can be manufactured as shown in FIG. Alternatively, the pedestal plate 103 may be pulled up until the center portion is cut off to solidify the workpiece, and then the bar member 105 may be pulled out.

  In the present invention, as shown in FIG. 11, the end 4A or 4B of the through hole 4 of the sheet-like microneedle 1 is brought into contact with a filling liquid tank 8 in which the filling liquid 9 is stored. Fill.

ただし、ｈ＝毛細管現象の高さ、T=表面張力（N/m）、θ=充填液と貫通孔内面との接触角（°）、ρ=充填液の密度（kg/m3）、g=重力加速度（9.80665m/sの2乗）、r=管の内径（半径：mm）The height at which the capillarity occurs is represented by equation (1).

Where h = height of capillary action, T = surface tension (N / m), θ = contact angle between filling liquid and the inner surface of through-hole (°), ρ = density of filling liquid (kg / m3), g = Gravitational acceleration (9.80665 m / s squared), r = inner diameter of pipe (radius: mm)

  Therefore, when the through hole height Hh ≦ the capillary action height h, the through hole 4 is filled with the filling liquid 9 at a filling rate of almost 100%. The filling rate does not necessarily have to be 100%, but it is preferable that the filling liquid 9 as the target substance is filled in a large amount. Also, if the filling rate is low, the position of the filling liquid 9 may be biased to form a cavity, and the filling liquid 9 may not be easily taken into the body from the skin. Therefore, it is preferable that the height of the through hole Hh ≦ the height of the capillary phenomenon h × 70%.

  The through hole height Hh is preferably not less than 50 μm and less than 1000 μm. If the through hole height Hh is too small, the distance from the skin surface where the tip of the needle peak 3 reaches is not sufficient, and if it is too large, the strength of the needle peak 3 may be insufficient, which is not preferable.

  The filling liquid 9 (target substance) is not particularly limited, but is a liquid, and is a liquefied medicinal component used as various medicines such as insulin, hormonal agents, antibodies, vaccines, collagen, hyaluronic acid, and the like. For example, a serum obtained by liquefying various cosmetic ingredients such as glucose, a nutrient solution obtained by liquefying various nutrients 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 decreases, and if the viscosity is too high, it is difficult to cause a capillary phenomenon, which is not preferable.

  Then, as shown in FIG. 12, the microneedle 1 filled with the filling liquid 9 is placed on the protective material 50 with the upper and lower ends of the through hole 4 open. The protective member 50 has a support portion 51 that supports the flat portion 2C of the base sheet 2 where the needle ridges 3 are not formed, 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 peak 3, and prevents anything from contacting the vertex of the through hole 4. This can prevent the filling liquid 9 in the through hole 4 from leaking to the outside.

  Note that the top surface 52 is not always necessary, and a part or all of the bottom surface 52 may be open. There is no limitation on the vertical direction of 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 top of the needle peak 3 (see FIG. 10), the height of the needle peak 3 can be maintained, and the height from the tip to the top of the through hole 4 in the needle peak 3 can be maintained. The region can serve to protect the through hole 4. Further, although not shown, the needle hole 3 may be offset from the vertex, and the through hole 4 may be inclined in a direction opposite to the offset direction. Thereby, the volume inside the through hole 4 can be increased by the amount of the 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 sticking the vertex 3A into the skin. When the microneedle 1 is pierced by the skin, the filling liquid 9 inside the through hole 4 comes into contact with the bodily fluid, so that the microneedle 1 is pulled by the bodily fluid by surface tension and is absorbed into the body. When a bioabsorbable polymer is used as the material of the needle peak 3, by leaving the microneedle 1 attached to the skin as it is, the needle peak 3 itself can be absorbed into the body.

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

<Operations and effects>
Hereinafter, the characteristics of the invention group extracted from the above-described embodiment will be described while showing problems and effects as necessary. In the following, for easy understanding, the corresponding configuration in each of the above embodiments is appropriately indicated in parentheses, but is not limited to the specific configuration indicated in parentheses. In addition, the meanings and examples of terms described in each feature may be applied as the meanings and examples of terms described in other features described in the same wording.

  In the microneedle manufacturing method of the present invention, a plurality of needle peaks (needle peaks 3) are formed, and the needle needles penetrate from the sheet surface (sheet front surface 2A) side on which the needle peaks are formed to the sheet rear surface (sheet rear surface 2B). The end of the through-hole of the sheet-like microneedle (microneedle 1) having the through-hole (through-hole 4) formed therein is brought into contact with the filling liquid (filling liquid 9), and the through-hole is filled with the filling liquid by capillary action. I do. In addition, the sheet surface side refers to all surfaces including the needle ridge portion and the flat portion where the needle ridge is not formed.

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

  h = capillary phenomenon height, T = surface tension (N / m), θ = contact angle (°) between filling liquid and inner surface of through hole, ρ = density of filling liquid (kg / m3), g = gravitational acceleration (9.80665 m / s squared), and r = the inner diameter (radius: mm) of the pipe, the height h of the capillary phenomenon represented by the equation (1) is 70% or more of the height Hh of the through hole. is there

  As a result, the filling rate of the filling liquid 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 continuity. When filled, the filling liquid can be smoothly injected without being stopped by air.

  By contacting the apex side of the needle crest with the filling liquid, compared with the method of contacting the back side of the sheet with the filling liquid, the portion to be contacted with the filling liquid is reduced, and excess filling liquid liquid is adhered. You don't have to.

  In the microneedle, the through hole is formed in the needle peak using a laser irradiated from a tip direction of the needle peak. Thereby, the through-hole can be easily and quickly formed with an arbitrary diameter, and a component melted by the laser is attached to the periphery of the through-hole to form a bulge, and the bulge forms contact with the outside. Since it can be prevented, it can play a role of protecting the filling liquid inside the through hole.

  The microneedle is characterized in that the through hole is formed by pulling out a rod-like member that has been previously penetrated when forming the needle ridge, and the rod-like member is pulled out in the root direction of the needle ridge. Accordingly, the root portion rises and the contact with the outside can be prevented by the rise, so that the filling liquid inside the through hole can be protected.

  Since the through hole is formed at a position shifted from the apex by a predetermined offset amount, the apex can play a role of protecting the through hole. Although there is no limitation on the offset amount, by securing an offset amount equal to or more than 1/4 of the radius of the needle peak, the strength near the needle peak can be maintained. Further, by setting the radius to less than 2.0 times, more preferably less than 1.5 times the radius of the needle peak, it is possible to reliably introduce the filling liquid into the skin. Note that 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. The radius of the needle ridge is defined as the distance from the intersection of the ridge line along the slope portion from the peak of the needle ridge and a plane extending from the plane of the sheet surface to the peak of the needle ridge. If the peak of the needle ridge is not completely at the center of the needle ridge, 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 a capillary phenomenon.

  The through hole is formed near a root portion of the needle ridge. Thus, the through-hole may be provided in a plane portion where the needle ridge is not formed, so that the strength of the needle ridge can be maintained.

A protective material (protective material) having an opposing surface facing the sheet, and a supporting portion (supporting portion 51) formed so as to protrude from the opposing surface and formed at a height higher than a height of a needle from a surface of the sheet to a peak of a needle. 50)
It is characterized in that the apex of the support portion and the flat portion of the sheet where the needle ridges are not formed are in contact with each other.

  Thus, the microneedles can be appropriately protected so that the tips of the through holes do not come into contact with each other.

  Since the two ends of the through hole are open, the manufacturing process can be simplified.

  In addition, the microneedle pierces the skin at the apex of the needle peak and contacts the bodily fluid inside the skin, thereby absorbing the filling liquid into the body using surface tension. This allows the microneedle to absorb the target substance into the user's body by a simple procedure without requiring any special pressurization or the like.

  Further, 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 of the support portion 151. When the user pours the filling liquid 9 such as a beauty liquid, a lotion, a special liquid, or the like, which is separately attached to the protective material 150 or owned by the user, the protective material 150 passes through the hole 155 to cover the entire area of the protective material 150. The filling liquid 9 spreads, and the filling liquid tank 8 is formed.

  The depth D of the support portion 151 in the protective material 150 is formed slightly larger than the height Hh of the needle peak 3 (for example, 0.05 to 0.5 mm). Therefore, the user simply pours the filling liquid 9 into the protective material 150 and mounts the microneedle 1 so that the vertex 3A of the needle peak 3 is positioned without contacting the bottom surface 152, and the user can easily fill the vertex 3A with the filling liquid. The filling liquid 9 can be filled inside 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 peak 3, and a hole or a gap is provided in the support portion 151 so that the liquid can flow 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 vertex 3 </ b> A is disposed slightly above the bottom surface 152 by the support portion 151, and the filling is performed by the capillary phenomenon. The liquid 9 can be easily filled.

  Further, as shown in FIG. 14, the filling liquid 9 can be sucked from the sheet back surface 2B side of the microneedles 1. In this case, for example, a prescribed amount of the filling liquid is dropped near the center of the flat tray 250, and this is used as the filling tank 8. While bending the microneedle 1, the microneedle 1 is set so that the vicinity of the center comes into contact with the filling tank 8 first, and the outside gradually contacts the tray 250 while taking care not to allow air to enter. 1 is placed on the tray 250. Thereby, 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, an outer frame 251 swelling from the bottom surface 252 is formed on the tray 250 for the purpose of preventing liquid leakage, but this is not essential. The tray 250 may also be used as a protective material for protecting the tip 3A of the microneedle 1, and may be separately attached or sold separately.

  As shown in FIG. 15, the offset amount from the root portion of the needle tip 2, that is, the offset amount from the tip of the needle tip is larger than the radius of the needle tip 2 and less than twice the radius of the needle tip 2, more preferably 1.5 times. The through-hole 4X may be provided so as to be set to less than. In other words, a through-hole is formed immediately beside the needle ridge. Even in this case, the filling liquid filled in the through-hole 4X can be supplied to the place where the skin is damaged by the needle peak 2, so that the same effect as when the through-hole is provided in the needle peak (the filling liquid of the skin is not filled). Penetration). The through-hole 4X can be formed before or after the needle ridge is formed, or simultaneously with the needle ridge. When the needle ridges are formed by molding, a through-hole may be provided at a position where there is no needle ridge in the mold, and the rod-shaped member may be penetrated.

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

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

1: Microneedle 2: Base sheet 2A: Sheet surface 2B: Sheet back surface 2C: Flat portion 3: Needle crest 3A: Apex 4: Through hole 4A: End 8: Filling liquid tank 9: Filling liquid

Claims (14)

A plurality of needle ridges are formed, and the end of the through-hole of the sheet-shaped microneedle in which a through-hole that penetrates from the sheet surface side where the needle ridges are formed to the sheet back side is brought into contact with the filling liquid, A method for producing a microneedle, characterized in that a filling liquid is filled in a through hole by a capillary phenomenon. 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 / m3), g = gravitational acceleration (9.80665 m / s squared), and r = the inner diameter (radius: mm) of the pipe, the height h of the capillary phenomenon represented by the equation (1) is 70% of the height Hh of the through hole. Is over

The method for producing a microneedle according to claim 1, wherein: The method for producing a microneedle according to claim 1, wherein a vertex side of the needle ridge is brought into contact with the filling liquid. The microneedle is
The method for producing a microneedle according to claim 1, wherein the through-hole is formed on the needle ridge by using a laser irradiated from a tip direction of the needle ridge. The microneedle is
At the time of needle ridge formation, the through-hole is formed by pulling out a rod member that has been previously penetrated,
The method for manufacturing a microneedle according to any one of claims 1 to 3, wherein the rod-shaped member is pulled out in a root direction of the needle ridge. The through hole,
The method for manufacturing a microneedle according to claim 1, wherein the microneedle is formed at a position shifted from the vicinity of the vertex by a predetermined offset amount. The method of manufacturing a microneedle according to any one of claims 1 to 6, wherein a height h of the through hole is 50 µm or more and less than 1000 µm. The method for manufacturing 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 so as to protrude from the facing surface and having a height higher than a needle height from the sheet surface to a peak of the needle,
The method for manufacturing a microneedle according to claim 1, wherein the apex of the support portion and a flat portion of the sheet on which the needle ridges are not formed are arranged to be in contact with each other. . 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,
The method for manufacturing a microneedle according to claim 1, wherein the microneedle is formed near a root portion of the needle ridge. A plurality of needle ridges are formed, a through-hole penetrating from the top or near the top of each needle ridge to the sheet back surface is formed, and the filling liquid is filled in the through-hole,
h = height of through hole, T = surface tension (N / m), θ = contact angle between filling liquid and inner surface of through hole (°), ρ = density of filling liquid (kg / m3), g = gravitational acceleration (9.80665 m / s squared), and r = the inner diameter (radius: mm) of the pipe, the height h of the capillary phenomenon represented by the equation (1) is 70% of the height Hh of the through hole. Is over

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

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