JP2016189844A - Microneedle patch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent warping of a microneedle sheet caused by the difference in a moisture content absorbed by the microneedle sheet from the skin between a sheet-like base material and a microneedle, and prevent stuffy feelings of the skin caused by a situation in which the absorbed moisture content is larger than a moisture content diffused from the microneedle sheet.SOLUTION: A microneedle patch is configured so that a sheet-like base material, a plurality of microneedles on the sheet-like base material, and an adhesive sheet that is permeated by moisture on a surface opposite to the surface having the microneedles of the sheet-like base material are laminated.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a microneedle patch for administering a target substance into the skin, and more particularly to a microneedle patch on which an adhesive sheet having a property of allowing moisture to pass is laminated.

  The microneedle patch includes a microneedle sheet in which a plurality of microneedles are arranged on a sheet-like base material, and an adhesive sheet that is laminated on a surface opposite to the surface on which the microneedles are arranged. A microneedle has a shape that hardly feels pain even when it is stabbed into the skin. By attaching the microneedle sheet to the skin, the microneedles stick into the skin, and a wide range of drugs can be administered.

  A soluble microneedle sheet that dissolves microneedles in the human body is composed of a target substance to be administered and a water-soluble material that is dissolved by moisture in the skin, such as dextran and hyaluronic acid, or moisture released from the skin. . In such a microneedle sheet, since the target substance is administered by dissolving the microneedles, it is necessary to stably hold it on the skin with an adhesive sheet or the like until the microneedles are completely dissolved.

  For example, Patent Document 1 discloses a microneedle patch in which the back surface of a microneedle sheet is covered with a low moisture permeable layer and the back surface is covered with a highly moisture permeable adhesive protective tape. This microneedle patch adjusts the speed of moisture dissipation from the microneedle sheet by sandwiching a low moisture permeable layer therebetween, and prevents warping.

JP 2011-167486 A

However, the microneedle patch disclosed in Patent Document 1 has the following problems because the diffusion of moisture absorbed from the skin by the microneedle sheet is excessively suppressed by the low moisture permeable layer. .
(1) Since the microneedle sheet is warped due to a difference in moisture retention between the surface of the microneedle sheet to which the adhesive protective tape is bonded and the surface of the microneedles, the adhesive protective tape tries to suppress the warpage. The user feels pain (2) The amount of water retained by the microneedle sheet is greater than the amount of water dissipated from the microneedle sheet, and the skin is muggy

  The present invention has been made to solve the above-described problems, and an object thereof is to improve the feeling of use of the microneedle patch.

  Hereinafter, a plurality of modes will be described as means for solving the problems. These embodiments can be arbitrarily combined as necessary.

  The microneedle patch of the present invention is a pressure-sensitive adhesive sheet having a property of allowing moisture to pass through a sheet-like substrate, a plurality of microneedles on the sheet-like substrate, and a surface of the sheet-like substrate opposite to the surface having the microneedles. Are laminated.

  In a preferred embodiment, the pressure-sensitive adhesive sheet has at least one through hole.

  In a preferred embodiment, the thickness of the center of the pressure-sensitive adhesive sheet is smaller than the thickness around the pressure-sensitive adhesive sheet.

  In a preferred embodiment, the ratio of the area of the through hole to the area of the pressure-sensitive adhesive sheet is 2.5 to 25%.

  The microneedle patch according to the present invention is configured such that a pressure-sensitive adhesive sheet having a property of allowing moisture to pass through is laminated on the surface opposite to the surface having the microneedles of the sheet-like substrate. Therefore, pain due to warping of the microneedle sheet and stuffiness of the skin can be prevented, and the feeling of use can be improved.

It is sectional drawing of the microneedle patch which concerns on one Embodiment of this invention. It is sectional drawing of the microneedle patch which has a through-hole in an adhesive sheet. It is sectional drawing of the microneedle patch in which the center of an adhesive sheet is formed thinner than the periphery. It is sectional drawing of the microneedle patch which concerns on the modification of embodiment of this invention.

  The microneedle patch of the present invention is a pressure-sensitive adhesive sheet having a property of allowing moisture to pass through a sheet-like substrate, a plurality of microneedles on the sheet-like substrate, and a surface of the sheet-like substrate opposite to the surface having the microneedles. Are laminated. Hereinafter, an exemplary embodiment of the microneedle patch of the present invention will be described.

<First embodiment>
First, a first embodiment according to the microneedle patch of the present invention will be described with reference to the drawings.

(Outline of microneedle seat)
FIG. 1 shows a microneedle patch 10. The microneedle patch 10 includes a sheet-like base material 12, a plurality of microneedles 11 formed on the sheet-like base material, and an adhesive sheet 14.

  The sheet-like substrate holds microneedles, and the shape and structure thereof are not particularly limited as long as they can hold a group of microneedles. The thickness of the sheet-like substrate 12 may be determined as appropriate according to the intended use of the microneedle sheet, and may be set to a thickness that can function as a microneedle sheet.

  The microneedles 11 may be conical or pyramidal, for example, or may have another shape. The size is set, for example, in a range where the height is 10 μm to 1 mm, the maximum bottom width is 10 μm to 1 mm, and the aspect ratio is 0.5 to 4.

(Raw material of micro needle)
The raw material of the microneedles 11 is a polymer substance that is harmless to the human body, and includes, for example, a resin that is harmless to the human body, a polysaccharide that is harmless to the human body, a protein that is harmless to the human body, and a biologically active substance derived therefrom.

  The polymer substance that is harmless to the human body as the raw material of the microneedles 11 preferably has at least one of the properties of in vivo solubility and biodegradability. Here, the in vivo solubility is a property that dissolves in vivo, and the in vivo degradability is a property that decomposes in vivo. By forming the microneedles 11 with a polymer substance having at least one of both properties, the microneedles 11 that have entered the skin are subjected to the action of at least one of dissolution and decomposition in the living body, Since it gradually changes over time, it does not remain in the skin for a long time as a solid.

  In addition, the biosoluble and / or biodegradable polymer substance forming the microneedles 11 is preferably water-soluble. In the case of a water-soluble polymer substance, the microneedles 11 are dissolved by moisture in the skin, so that the target substance can be easily introduced into the skin using the microneedles 11.

  Examples of polysaccharides that are water-soluble and have at least one of in vivo solubility and biodegradability and are harmless to the human body and compounds derived therefrom are maltose, dextran, water-soluble chitosan, and pullulan. , Sodium chondroitin sulfate, sodium hyaluronate and glycogen. Examples of proteins harmless to the human body having at least one of water solubility, in vivo solubility and biodegradability and compounds harmless to the human body derived therefrom include serum albumin and serum α-acid glycoprotein. It is done. Examples of a resin that is at least one of water-soluble and in-vivo-soluble and biodegradable and harmless to the human body and compounds derived from it are biodegradable polymers that are harmless to the water-soluble human body. And compounds derived therefrom. Examples of biodegradable polymers that are harmless to the water-soluble human body and compounds that are harmless to the human body include carboxyvinyl polymers and polyethylene glycol (PEG), which is a water-soluble and biocompatible polymer, and lactic acid / glycolic acid. -A block polymer having water solubility and biodegradability obtained by block copolymerization of a copolymer (PLGA), polycaprolactone (PCL) or polylactic acid (PLA).

  Examples of the non-water-soluble resin having at least one of in vivo solubility and biodegradability are harmless to the human body and compounds derived from it are polylactic acid, polyglycolic acid, and the like. Polydioxanone may be mentioned.

  Note that the microneedle may be formed from at least one of the above materials. Further, at least two different raw materials may be formed in layers, or at least two different raw materials may be mixed and formed. The above raw materials can also be used as a target substance, and the microneedles 11 may be formed only from the target substance. For example, the microneedles 11 may be formed only from sodium hyaluronate.

(Material for sheet-like substrate)
The material of the sheet-like base material 12 is not particularly limited as long as it can hold the microneedles 11 and allows the microneedles to pierce the skin, and is the same as the above-described raw material used for the microneedles. May be different or different.

(Adhesive sheet)
In the microneedle patch of the present invention, a pressure-sensitive adhesive sheet having a property of allowing moisture to pass is laminated on the surface opposite to the surface having the microneedles of the sheet-like substrate. Therefore, the material of the adhesive sheet has a property of diffusing moisture absorbed from the skin by the microneedle sheet. Examples of such a material include resins such as cellulose, polyurethane, polyethylene, and polyamide. For example, a base material obtained by processing these into a woven fabric, a nonwoven fabric, a film, or the like is used. The moisture absorbed from the skin by the microneedle sheet includes sweat present on the skin surface.

  The pressure-sensitive adhesive sheet is preferably processed with through holes (see FIG. 2). You may form a through-hole only in the base material of the adhesive sheet 14. FIG. Moreover, you may form through a base material and an adhesive. The shape of the through hole is not particularly limited, and may be a circular shape, an elliptical shape, a polygonal shape, or the like. By processing the through hole, the amount of water released from the microneedle sheet 13 can be easily adjusted. At this time, when the material of the sheet-like base material 12 in contact with the skin is water-soluble, the amount of dissolution of the sheet-like base material is maintained moderately, so that when the microneedle patch is removed from the skin The melted sheet-like base material does not stick to the skin, and the usability can be improved.

  The thickness of the pressure-sensitive adhesive sheet 14 is preferably 20 to 400 μm. If it is less than 20 μm, it is difficult to handle because it is thin, and wrinkles when applied to the skin. On the other hand, when it exceeds 400 μm, the feeling of use decreases.

  The amount of water diffused from the microneedle sheet 13 through the through hole is determined by the ratio of the area of the through hole to the area of the adhesive sheet 14, that is, the opening ratio. The aperture ratio is preferably 2.5 to 25%. If it is less than 2.5%, the amount of water released from the microneedle sheet 13 is reduced, and the skin is stuffy and the microneedle sheet is warped. On the other hand, if it exceeds 25%, the amount of water dissipated from the microneedle sheet 13 becomes excessive, a difference in the amount of moisture retained between the microneedles and the sheet-like base material, and warping of the microneedle sheet occurs. By adjusting the aperture ratio in this way, the moisture retention amount of the microneedle sheet 13 can be maintained moderately, and the skin can be prevented from being steamed and the microneedle sheet being warped.

  The shape of the pressure-sensitive adhesive sheet 14 can be a circle, an ellipse, or a slanting ball. Other shapes may also be used. The size of the pressure-sensitive adhesive sheet 14 is preferably 1.5 to 3.0 mm larger than the outer edge of the microneedle sheet 13 in order to stably hold the microneedle sheet 13 in close contact with the skin.

  The pressure-sensitive adhesive is preferably made of a pressure-sensitive adhesive that has little skin irritation and safety. Examples of such adhesives include acrylic adhesives, rubber adhesives, silicon rubber adhesives, vinyl ether adhesives, urethane adhesives, and the like. Among these, acrylic adhesives and urethane adhesives are preferable because they have high water permeability.

(Manufacturing method of microneedle patch)
The microneedle sheet 13 is manufactured, for example, by pouring an aqueous solution of sodium hyaluronate into a mold in which the shape of the microneedles 11 is carved and drying the mold. If the target substance is sodium hyaluronate, the microneedle sheet 13 may be formed using an aqueous solution of sodium hyaluronate as a main component. When the target substance is sodium hyaluronate and other physiologically active substances, the microneedle sheet 13 can be produced by pouring an aqueous solution of sodium hyaluronate to which other physiologically active substances have been added into a mold and drying. Good. Methods other than those described above may be used as methods for adding other physiologically active substances. For example, they may be added by applying after drying.

  The microneedle patch 10 can be manufactured by bonding the adhesive sheet 14 to the manufactured microneedle sheet 13 and peeling it from the mold. At this time, if the through-hole is processed in the pressure-sensitive adhesive sheet, the microneedle sheet 13 and the pressure-sensitive adhesive sheet 14 can be manufactured without involving bubbles.

<Second embodiment>
Next, a microneedle patch according to a second embodiment of the present invention will be described. The second embodiment is different from the first embodiment in that the thickness of the center of the adhesive sheet 14 is smaller than the surrounding thickness (see FIG. 3).

  The material of the base material of the pressure-sensitive adhesive sheet 14 can be the same as that of the first embodiment, but the water absorbed by the microneedle sheet 13 is diffused through the portion having a small thickness, so that it is difficult for water to pass through. Even a material having the above can be used. Such materials include thermoplastic resins such as polyethylene, polypropylene, and polyethylene terephthalate.

  The portion where the thickness of the pressure-sensitive adhesive sheet 14 is small should correspond to the region where the microneedles 11 are formed. If it does in this way, it can make it easy to dissipate the water | moisture content which the microneedle absorbed from the inside of skin.

  In this microneedle patch, the thickness around the adhesive sheet is not changed, and only the thickness at the center is reduced, so that the adhesive sheet is flexible while maintaining the strength of the adhesive sheet, and the microneedle sheet follows the skin well. Can be made.

  In addition, the form which a part thickness becomes small may be sufficient by forming a some recessed part in the center of an adhesive sheet (refer FIG. 4). In such a microneedle patch, the amount of moisture absorbed by the microneedle sheet can be easily adjusted by adjusting the number and depth of the recesses. Moreover, since the surface area of the center of the adhesive sheet 14 increases, the diffusion time of the water absorbed by the microneedle sheet can be easily adjusted.

  In the first and second embodiments, the pressure-sensitive adhesive formed on the pressure-sensitive adhesive sheet 14 has been described as an example of fixing the microneedle sheet 13 to the skin. However, the present invention is not limited to such a form. For example, the microneedle sheet 13 may be wound using a bandage while being stabbed into the skin. Also, a string-like member such as a string or rubber is attached to both ends of a sheet made of a material that allows moisture to pass through, and a microneedle sheet 13 is attached to the sheet and attached to the body with the string-like member, It may be hooked on the body.

  As described above, the microneedle patch of the present invention can be obtained.

10: Microneedle patch 11: Microneedle 12: Sheet-like base material 13: Microneedle sheet 14: Adhesive sheet

Claims (4)

A sheet-like substrate;
A plurality of microneedles on the sheet-like substrate;
A microneedle patch, characterized in that an adhesive sheet having a property of allowing moisture to pass through is laminated on a surface opposite to the surface having the microneedles of the sheet-like substrate.   The microneedle patch according to claim 1, wherein at least one through-hole is formed in the pressure-sensitive adhesive sheet.   The microneedle patch according to claim 1, wherein the thickness of the center of the pressure-sensitive adhesive sheet is smaller than the thickness around the pressure-sensitive adhesive sheet.   The microneedle patch according to claim 2, wherein a ratio of an area of the through hole to an area of the pressure-sensitive adhesive sheet is 2.5 to 25%.

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