JP2022043919A - Cosmetic microneedle - Google Patents

Abstract

To provide a beauty care sheet extremely easily and device-wise exerting effects, compared with the conventional method, in order to fill grooves formed in fine wrinkles, saggy wrinkles, etc. on the skin and recover a youthful plump skin.SOLUTION: The present invention relates to a microneedle array for dermal application, using a water-soluble polymer as a base and including hydroxyapatite particles dispersed in the base, and a beauty sheet consisting of the microneedle array for dermal application and aiming at the care for skin grooves, the beauty sheet consisting of the microneedle array for dermal application and aiming at the care for wrinkles between eyebrows, wrinkles on nasolabial folds and breast cleavage. The particle size of the hydroxyapatite particles is preferably equal to or less than 5 μm.SELECTED DRAWING: Figure 1

Description

The present invention relates to the technical field of microneedles applied to the skin. More specifically, the present invention relates to a microneedle array for administration of a composition containing hydroxyapatite, which is easy for collagen to settle and is effective for skin growth by proliferation.

The skin is composed of the epidermis and the dermis. The outermost epidermis is formed in the stratified squamous epithelium and the underlying basement membrane. The epidermis does not contain blood vessels and is nurtured by the diffusion action from the dermis. The epidermis is mainly composed of keratinocytes, and black cells and Langerhans cells are also present. This skin layer acts as a barrier between the body and the external environment, retaining water in the body and preventing the invasion of harmful chemicals and pathogens.

The dermis lies beneath the epidermis and contains multiple structures, including blood vessels, nerves, hair follicles, smooth muscle, glands and lymphoid tissue. The dermis (or corium) is typically 0.1-3 mm thick and is a major component of human skin. The dermis is composed of connective tissue with a network structure, collagen fibrils that are predominantly present and supportive, and elastin fibers that provide flexibility. The main cell types that make up the dermis are fibroblasts, adipocytes (fat reservoirs) and macrophages.

The cuticle is below the dermis and is important for attaching the skin to the underlying bones and muscles and for supplying blood vessels and nerves to the skin. The cuticle is produced in loose connective tissue and contains fibroblasts, macrophages and adipocytes. Adipocytes play a major role in the fat storage function of the subcutaneous layer of the cuticle. Fat acts as a filling material and as an insulator of the body from the external environment.

Facial aging is the result of multiple factors, among which are inherent skin changes, the effects of gravity, facial muscle activation, skin loss or migration, bone loss, and tissue that cause mechanical facial wrinkles. It is due to reduced elasticity and harsh environmental conditions, specifically sunlight or UV radiation and exposure to contaminants. The skin ages as the epidermis begins to thin, flattening its junction with the dermis. Collagen decreases with age in humans, and the collagen fiber bundles that give the skin's turgor loosen and decrease in strength. When the skin loses elasticity, it becomes less tolerant of tension. With gravity, muscle damage and tissue changes, the skin begins to shrink and wrinkle. Lack of water and disruption of cell-cell bonds can also reduce the barrier function of the skin and increase the pore size of the skin.

Efforts have been made to develop and use compositions that repair skin defects such as shrinkage wrinkles, or that increase the tissue of interest, in order to improve the appearance of the skin, especially the skin of the face. rice field.

Currently, there are many known dermal fillers for skin augmentation such as autotransplantable materials, allogeneic products, heterogeneous products and synthetic products. Available dermal fillers are biodegradable natural substances (collagen, gelatin, hyaluronic acid, dextran, etc.), biodegradable synthetic polymers (poly-L-lactic acid, carboxymethyl cellulose, etc.), non-biodegradable synthetic polymers (poly-L-lactic acid, carboxymethyl cellulose, etc.). And silicones, etc.) and combinations thereof.

Biocompatible ceramic skin-enhancing materials such as hydroxyapatite are known to be efficient skin-enhancing materials due to their properties.

Hydroxyapatite (Ca ₅ (PO ₄ ) ₃ (OH)) is a naturally occurring inorganic form of calcium phosphate. Hydroxyapatite contains an inorganic component of bone and therefore becomes biocompatible and non-immunogenic when introduced into the subject's body. Hydroxyapatite, when injected as a small microsphere, acts as a scaffold and promotes new tissue formation similar to the surrounding environment. Inside the skin, such as the dermis, attached hydroxyapatite particles are known to support fibroblast endometrial and novel collagen formation.

There are microneedles as a measure for intradermal administration of hydroxyapatite regardless of injection or surgery. Patent Document 1 discloses a device and a method for delivering a dermal filler composition to a target skin using a hollow microneedle device. The present disclosure is a miniaturized version of the conventional injection method.

Patent Document 2 discloses a device in which hydroxyapatite is loaded into a microneedle with an applicator and inserted into the skin. This content aims at intradermal delivery of hydroxyapatite having a particle size of 5 microns or more by a system integrated with an applicator microneedle having a complicated structure.

International Publication No. 2008/072229 Japanese Patent No. 6546091

An object of the present invention is to fill a groove formed in a shrinkage wrinkle or a sagging wrinkle of the skin, and to restore a youthful bulge to the skin. The goal is to provide a cosmetology care sheet that is much easier to achieve both effectively and effectively.

The present inventors have succeeded in producing a microneedle array in which a substance soluble in the body is selected as the base of the microneedles, the particle size of hydroxyapatite is adjusted within a predetermined range, and the particles are dispersed in the base. However, when a test was conducted using the microneedle array, it was found that the intended purpose was achieved, and the present invention was completed.

The present invention is as shown below.
[1] A skin-applied microneedle array using a water-soluble polymer as a base and hydroxyapatite particles dispersed in the base.
[2] A cosmetological sheet for the purpose of caring for skin grooves, which comprises a skin-applied microneedle array in which hydroxyapatite particles are dispersed in the base using a water-soluble polymer as a base.
[3] The purpose is to care for glabellar wrinkles, nasolabial fold wrinkles, or intermammary grooves, which consist of a skin-applied microneedle array using a water-soluble polymer as a base and hydroxyapatite particles dispersed in the base. Beauty sheet.
[4] The microneedle array according to [1] or the beauty sheet according to [2] or [3], wherein the hydroxyapatite particles have a particle size of 5 μm or less.
[5] The microneedle array or beauty sheet according to [4], wherein the hydroxyapatite particles have a particle size of 1 μm or less.
[6] The microneedle array or beauty sheet according to any one of [1] to [5], wherein the content of the hydroxyapatite particles in the base is 0.0001% by mass or more and 40% by mass or less. ..
[7] The microneedle array or beauty sheet according to any one of [1] to [5], wherein the content of hydroxyapatite in the base is 0.001% by mass or more and 30% by mass or less.
[8] The microneedle array or beauty sheet according to any one of [1] to [7], wherein the needle size of the microneedle is 0.1 mm or more and 1.0 mm or less.
[9] A water-soluble polymer selected from the group consisting of sodium hyaluronate and its derivatives, collagen, proteoglycan, hydroxypropyl cellulose, chondroitin sulfate, carboxymethyl cellulose, polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol (PVA) and dextran. The microneedle array or beauty sheet according to any one of [1] to [8], which is two or more kinds.
[10] The microneedle array or beauty sheet according to [9], wherein the sodium hyaluronate and its derivative are PEG-grafted sodium hyaluronate, and hydroxyapatite fine particles are dispersed in the PEG-grafted sodium hyaluronate.
[11] The microneedle array or beauty sheet according to any one of [1] to [10], wherein hydroxyapatite fine particles are dispersed in the base by a surfactant.
[12] The microneedle array or cosmetological sheet according to [11], wherein the surfactant is POE (20) oleyl ether.
[13] The microneedle array or beauty sheet according to any one of [1] to [12], wherein the microneedle array is a substrate having a thickness of 100 μm or less and has a flexible substrate portion.
[14] The microneedle array or beauty sheet according to any one of [1] to [13], wherein the base of the microneedle array contains 2% by mass or more of a water-soluble low molecular weight compound in addition to the water-soluble polymer.
[15] The microneedle array or beauty sheet according to any one of [1] to [14], wherein the back surface of the microneedle array is lined with a hydrophobic or insoluble film.

The present invention relates to a microneedle array containing particulate hydroxyapatite (HAP) as a skin-enhancing composition. Specifically, the microneedle array of the present invention has a needle length of 1 mm or less in which fine particle HAP of 5 μm or less is uniformly dispersed in a soluble base in the skin, and is an undesired shrinkage of the skin to be dissolved. Wow, useful for filling sagging wrinkles. According to the present invention, the microneedles periodically inject HAP microparticles in the soluble base in the skin into the epidermal and dermis layers of the subject skin, where they accumulate for a long period of time, filling and growing collagen. Continue to induce the effect.

It is a schematic diagram which shows the use period and the measurement schedule in the effectiveness test of the microneedle array of this invention.

The microneedle array of the present invention is a microneedle array in which fine particle HAP is uniformly dispersed in a soluble base in the skin, and is composed of a substrate and a plurality of microneedles on the substrate, and is integrated with a water-soluble polymer as a base. Is formed.
The cosmetological sheet of the present invention may be a cosmetological sheet for the purpose of caring for a skin groove portion, or may be a cosmetological sheet for the purpose of caring for a wrinkle between the eyebrows, a wrinkle of a nasolabial fold, or a groove between the breasts.

Base of Microneedle Array (or Beauty Sheet) The base of the microneedle array is a water-soluble polymer. When a microneedle array containing HAP uniformly using such a material is produced by a conventional method, HAP is contained not only in the microneedle portion but also in the substrate portion. Such a microneedle array may be a microneedle array that does not include HAP in the substrate portion. When this microneedle array is applied to a site where the appearance of facial skin is desired to be improved, the microneedle portion can reach the epidermis and the dermis, and the target site of HAP contained by the intradermal dissolution of the microneedle base. Allows delivery to.

Examples of the water-soluble polymer include sodium hyaluronate and its derivatives (eg, polyethylene oxide-grafted sodium hyaluronate, PEG-grafted sodium hyaluronate), collagen, proteoglycan, hydroxypropyl cellulose, chondroitin sulfate, carboxymethyl cellulose, polyvinylpyrrolidone, and the like. Examples thereof include polyethylene glycol, polyvinyl alcohol (PVA) and dextran, and one or a mixture of two or more selected from these may be used. In particular, sodium hyaluronate or a derivative thereof is preferable.

Hyaluronic acid, which typically uses sodium salts, is a type of glycosaminoglycan (mucopolysaccharide) and has a structure in which the disaccharide units of N-acetylglucosamine and glucuronic acid are linked. Examples of hyaluronic acid include hyaluronic acid derived from organisms isolated from chicken combs, umbilical cords and the like, hyaluronic acid derived from cultures mass-produced by lactic acid bacteria, streptococci and the like. Since biological hyaluronic acid cannot completely remove collagen possessed by the organism from which it is derived, and the remaining collagen may have an adverse effect, collagen-free culture-derived hyaluronic acid is preferable. Therefore, it is preferable that the hyaluronic acid contains 50% by mass or more of the hyaluronic acid derived from the culture.

When preparing a microneedle array using a water-soluble polymer substance selected from sodium hyaluronate or a derivative thereof as a component, the microneedle array molded from these polymer substances becomes hard as the weight average molecular weight decreases. It becomes easy to pierce the application site, and conversely, when the weight average molecular weight increases, the mechanical strength improves and becomes tenacious, so that it becomes flexible and tends to be easily applied to bending of the gums and the like. For the purposes of the present invention, the weight average molecular weight is preferably 50 to 2 million.

When the microneedle array is applied to the skin, it has an appropriate hardness and is hard to break. Therefore, from a mixture of a high molecular weight polymer substance having a weight average molecular weight of 100,000 or more and a low molecular weight polymer substance having a weight average molecular weight of 50,000 or less. Microneedle arrays may be formed. The weight average molecular weight of the high molecular weight polymer substance may be 50,000 or more, preferably 2 million or less. Further, the weight average molecular weight of the low molecular weight polymer substance may be 50,000 or less, preferably 1000 or more. In the present invention, the weight average molecular weight is a value measured by gel permeation chromatography (GPC).

The ratio when the high molecular weight polymer substance and the low molecular weight polymer substance are mixed varies depending on the type of each polymer substance and the weight average molecular weight. However, in general, it is preferably 1% by mass or more of the high molecular weight polymer substance and 99% by mass or less of the low molecular weight polymer substance.
The PEG-grafted sodium hyaluronate is described in International Publication No. 2017-010518 and can be suitably used in the present invention as well.

A solubilizer may be added to the above polymer substance in order to promote the dissolution of the microneedles in the skin. Examples of the solubilizer include monosaccharides such as trehalose and glucose, disaccharides, glycerin, propylene glycol (PG), butylene glycol (BG), and polyhydric alcohols such as polyethylene glycol (PEG). The amount of the solubilizer added is preferably 1% by mass or more and 50% by mass or less as the concentration in the base.

The base of the microneedle array can contain a water-soluble low molecular weight compound in addition to the water-soluble polymer. The water-soluble low molecular weight compound is a monosaccharide, a disaccharide, or a polyhydric alcohol used as the above-mentioned soluble agent, and has a molecular weight of 500 or less. Examples of the monosaccharide include glucose, fructose and the like, and examples of the disaccharide include sucrose, lactose, trehalose, maltose and the like. Examples of the polyhydric alcohol include glycerin, propylene glycol (PG), butylene glycol (BG), polyethylene glycol (PEG) 200, PEG400 and the like.
The amount of the water-soluble low molecular weight compound added is 0.1% by mass or more and 50% by mass or less, preferably 0.5% by mass or more and 40% by mass or less, and more preferably 1% by mass as the concentration in the base. It is 30% by mass or less.

A surfactant may be added to uniformly disperse the HAP in the water-soluble base. As a surfactant,
Nonionic surfactants are preferred. In particular, a water-soluble surfactant is more preferable. The amount added is 1: 0.001 to 1: 100 with respect to the mass of HAP. Examples of the surfactant of the coating liquid for microneedles of the present invention include polysorbate 80, polysorbate 40, polysorbate 20, etc. Polyoxyethylene sorbitan monohigher fatty acid ester, polyoxyethylene (5) cetyl ether, polyoxyethylene (20) cetyl. Polyoxyethylene alkyl ethers such as ether, or mixtures thereof can be preferably used.

Shape of Microneedle Array The height of the microneedles is preferably 50 μm or more and 1,000 μm or less, and more preferably 100 μm or more and 250 μm or less. Less than 50 μm is disadvantageous for delivery of local anesthetics. If it exceeds 1,000 μm, it may cause pain and bleeding at the time of application.

It is desirable that the tip of the microneedle is a circle having a diameter of 1 μm or more and a diameter of 50 μm or less, or a plane having the same area. Within this range, it is advantageous for intradermal delivery of microneedles. Examples of the needle shape include a rod shape, a truncated cone shape, and a conned shape, and a truncated cone shape or a conned shape is preferable.

The thickness of the substrate of the microneedle array is preferably 5 μm or more and 100 μm or less, and more preferably 10 μm or more and 60 μm or less.

The shape of the substrate of the microneedle array can be appropriately set according to the application site, and examples thereof include a circle, an ellipse, a triangle, a quadrangle, and a polygon. The size of the shape is usually represented by a diameter (major axis) or a side (long side) length of 2 mm or more and 200 mm or less, preferably 5 mm or more and 100 mm or less. Further, when the size of the microneedle array is expressed by an area, it is usually 5 mm ² or more and 2000 mm ² or less, and 10 mm ² or more and 1000 mm ² or less is preferable.

HAP
The active ingredient contained in the microneedle array of the present invention is HAP. HAP particles delivered into the skin promote fibroblast endothelium and new collagen formation. Since the promotion of collagen formation reacts from the surface of HAP particles, the effect of promoting collagen formation of HAP and reducing wrinkles differs depending on the particle size even if the same amount of HAP is delivered into the skin. That is, it is desirable that the particle size is small. The particle size of the HAP of the present invention is preferably 5 μm or less, more preferably 2 μm or less, and even more preferably 1 μm or less. If the particle size is 5 μm or more, the collagen forming effect is good, but the surface area per the same weight is small, and therefore the collagen forming effect is also small. Further, since the diameter of the tip of the microneedle is a circular plane of 1 μm or more, if the particle size of HAP is 5 μm or more, it is disadvantageous for the formation of the needle.

In addition to the above HAP, additives usually contained as pharmaceuticals and cosmetics may be contained. The concentration of the additive contained in the microneedle array of the present invention can be set in an appropriate range according to the type of the additive, the purpose of the addition, and the like.

The concentration of HAP in the base is 0.0001% by mass or more and 40% by mass or less, more preferably 0.001% by mass or more and 30% by mass or less. Here, the concentration of HAP in the base is the mass in the total weight of the microneedle array. If the concentration of HAP in the base is 0.0001% by mass or less, the skin anti-wrinkle effect is difficult to be exhibited, and if it is 40% by mass or more, the microneedles become brittle and the skin insertion tends to be difficult.

The method for producing the microneedle array of the present invention is not particularly limited, and may be produced by any conventionally known method. For example, the water-soluble polymer and HAP may be produced in a mold in which the shape of the microneedle is formed. If necessary, an aqueous solution containing other components is cast, dried, and then peeled off. The peeled microneedle array sheet is cut and used according to the shape of the application site of the skin.

The microneedle array of the present invention is conveniently used as the following microneedle patch.

Microneedle patch The microneedle patch of the present invention comprises the microneedle array and a support provided on the back surface of the microneedle array. Here, the back surface of the microneedle array is a substrate portion on the side opposite to the surface on which the microneedle protrudes. A support is not essential, but a support is easy to handle and can prevent slipping from the application site. A microneedle patch lined with a hydrophobic or insoluble film as a support on the back surface of the microneedle array is an embodiment of a cosmetic anti-wrinkle formulation.
A microneedle patch can be attached to the skin and quickly dissolved from the back surface with water or a liquid such as lotion, milky lotion, or beauty essence.

The pharmaceutical form in the present invention can be in various forms. They will be described in sequence.
1. 1. A microneedle patch in which a polymer film is lined as a support on the back surface of a dried microneedle array manufactured by the above method for manufacturing a microneedle array. This pharmaceutical product is integrated with the polymer film on the back surface of the microneedle array with an adhesive or adhesive. The size of the microneedle array and the polymer film may be treated so that the polymer film has a larger size and has skin adhesion on the film surface. The polymer film may be porous or water permeable, such as a woven fabric. Typically, a plastic sheet or film such as polyethylene, polypropylene, polyethylene terephthalate, ethylene vinyl acetate copolymer (EVA); a paper sheet such as sterile paper, cellophane, non-woven fabric, woven fabric and the like can be mentioned.

The size of the support is preferably larger than that of the microneedle array in order to reinforce the skin adhesion of the microneedle array from the back surface. The support can be set in a size and shape that is easy to handle depending on the application site, and for example, it is appropriate to increase the size by about 3 to 20 mm from the outer edge of the microneedle array. The thickness of the support may be equal to, thicker or thinner than the thickness of the microneedle array substrate, and can support a flexible and thin microneedle array and is easy to handle. Can be set as appropriate.

The support is preferably skin-adhesive in order to reinforce the skin adhesion of the microneedle array from the back.

One embodiment for ensuring the skin adhesiveness of the support is a support in which the support is coated with an adhesive substance, that is, the support is coated with an adhesive. Here, examples of the adhesive substance include adhesives usually used in patch preparations, and for example, grades of acrylic-based, silicon-based, and rubber-based adhesives having wet surface adhesiveness are preferable.

The microneedle patch of the present invention can be manufactured by covering the back surface of the microneedle array with a support.

The present invention will be described below by exemplifying examples, but the present invention is not limited to the examples.

Example 1
Weigh 2.5 parts by mass (purchased from Waken Yakuhin Co., Ltd.) of hydroxyapatite (average particle size = 2 μm) and 50 parts by mass of sodium hyaluronate (FCH-SU, Kikkoman), and add water to make 10% by mass of solid content. Solution was prepared. The aqueous solution was poured into a Conide mold having a needle length of 200 μm and a microneedle substrate diameter of 10 mm, dried at room temperature for 24 hours, and die-cut to produce a microneedle array. Then, a polyethylene (PE) adhesive film was adhered to the back surface of the array (microneedle substrate thickness = 40 to 50 μm, support thickness = 40 to 60 μm).

Examples 2 to 7, Comparative Examples 1 to 3
The microneedle preparation containing the base and hydroxyapatite shown in Table 2 was produced according to the method described in Example 1.
As a comparative example, a formulation of gel ointment (Comparative Example 2) was produced based on the composition shown in Table 1.

Test Example 1
Outline of efficacy test 1) Sample Examples 1 and 2 and Comparative Examples 1, 2 and 3
2) Application site under both eyes of the panelist 3) How to use After washing the face and preparing the face with basic cosmetics, after confirming that no water or oil remains on the face, apply it to each area before going to bed, and the next morning. I peeled it off.
4) Application frequency Each sample is used every other day for 4 weeks. After that, in order to discontinue use and confirm the sustainability of the effect, skin measurements were performed 8 weeks after the start.
5) Number of panelists 4 people 6) Measurement items Replica analysis of wrinkles around the eyes (area)
7) Measurement time / schedule Figure 1 shows the outline.

<Measurement method>
Wrinkles near the eyes were analyzed using the 3D image analysis system Primos lite 4530 (GFMesstechnik GmbH).
The area% of the wrinkled part was image-analyzed. The results are shown in Table 1.

In Comparative Examples 1 and 1, the wrinkle-reducing effect was observed after 4 weeks of use, probably due to hyaluronic acid, not the effect of HAP. From Examples 1 and 2, it is judged that the effect of HAP persists even after 2 weeks from the discontinuation.

Test Example 2
Add HAP in the base solution for microneedle molding (5-10% by mass water-soluble polymer aqueous solution), stir at high speed, and after standing for 15 minutes, determine the dispersibility of HAP in the base solution depending on the presence or absence of precipitation of HAP. confirmed. The molding rate was calculated by counting the number of needles that could be molded normally in the microneedle patch that could be molded. Furthermore, the brittleness of the patch (evaluated by whether the patch has sufficient toughness, specifically, whether the patch can be bent 90 degrees and broken) was confirmed. The results are shown in Table 2.

From Table 2, as shown in Examples 3 to 7, the microneedle formability is good and the toughness is also sufficient. From the reference example, it can be seen that if the particle size of HAP is too large, it is impossible to mold the HAP-containing microneedles, and even if the particle size is small, the content is large and brittle.

Claims (15)

A skin-applied microneedle array using a water-soluble polymer as a base and hydroxyapatite particles dispersed in the base. A cosmetological sheet for the purpose of caring for skin grooves, which comprises a skin-applied microneedle array in which hydroxyapatite particles are dispersed in the base using a water-soluble polymer as a base. A cosmetology that uses a water-soluble polymer as a base and consists of a skin-applied microneedle array in which hydroxyapatite particles are dispersed, for the purpose of treating glabellar wrinkles, nasolabial fold wrinkles, or intermammary grooves. Sheet. The microneedle array according to claim 1 or a cosmetological sheet according to claim 2 or 3, wherein the hydroxyapatite particles have a particle size of 5 μm or less. The microneedle array or beauty sheet according to claim 4, wherein the hydroxyapatite particles have a particle size of 1 μm or less. The microneedle array or beauty sheet according to any one of claims 1 to 5, wherein the content of the hydroxyapatite particles in the base is 0.0001% by mass or more and 40% by mass or less. The microneedle array or beauty sheet according to any one of claims 1 to 5, wherein the content of hydroxyapatite in the base is 0.001% by mass or more and 30% by mass or less. The microneedle array or beauty sheet according to any one of claims 1 to 7, wherein the needle size of the microneedle is 0.1 mm or more and 1.0 mm or less. One or two water-soluble polymers selected from the group consisting of sodium hyaluronate and its derivatives, collagen, proteoglycan, hydroxypropyl cellulose, chondroitin sulfate, carboxymethyl cellulose, polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol (PVA) and dextran. The microneedle array or beauty sheet according to any one of claims 1 to 8 as described above. The microneedle array or beauty sheet according to claim 9, wherein the sodium hyaluronate and its derivative are PEG-grafted sodium hyaluronate, and hydroxyapatite fine particles are dispersed in the PEG-grafted sodium hyaluronate. The microneedle array or a beauty sheet according to any one of claims 1 to 10, wherein hydroxyapatite fine particles are dispersed in the base by a surfactant. The microneedle array or cosmetological sheet according to claim 11, wherein the surfactant is POE (20) alkyl ether. The microneedle array or beauty sheet according to any one of claims 1 to 12, wherein the microneedle array is a substrate having a thickness of 100 μm or less and has a flexible substrate portion. The microneedle array or beauty sheet according to any one of claims 1 to 13, wherein the base of the microneedle array contains 2% by mass or more of a water-soluble low molecular weight compound in addition to the water-soluble polymer. The microneedle array or beauty sheet according to any one of claims 1 to 14, wherein the back surface of the microneedle array is lined with a hydrophobic or insoluble film.

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