JP2020000345A - Microneedle device - Google Patents

Abstract

To provide a microneedle device that allows a color material to be easily arranged at a target part of the skin.SOLUTION: A microneedle device includes: a pressure sensitive adhesive sheet having a base material sheet and an adhesive layer laminated on the base material sheet; and a microneedle having a substrate, one surface of which comes in contact with the adhesive layer of the pressure sensitive adhesive sheet, and a plurality of projections including a color material formed on the other surface of the substrate. In a plane view, part of the outer periphery of the substrate constitutes part of the outer periphery of the microneedle device, and the arrangement density of the projections becomes greater toward the part of the outer periphery of the substrate.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a microneedle device.

  Among cosmetics used to beautify and show attractiveness of a human body, there are cosmetics for coloring such as eyeshadow, lipstick, and blusher.

  These cosmetics are generally used at the beginning of the day and are washed off the skin at the end of the day. Also, these cosmetics may be removed by sweat or meals in the middle of the day. If these cosmetics are removed in the middle of the day, the user will need to use the cosmetics again on the skin, and some users find this burdensome.

  In recent years, tint type cosmetics capable of continuously coloring eyebrows and lips have been proposed (see Patent Document 1).

  The percutaneous absorption method, which is a method of permeating a substance such as a drug through the skin and administering the substance to the body, is used as a method that can easily administer the substance without causing pain to the human body. .

  In the field of transdermal administration, there has been proposed a method of perforating the skin using a microneedle having a needle on the order of μm and administering a drug or the like into the skin (see Patent Document 2).

JP 2000-319127 A JP-A-48-93192

  However, the tint type cosmetics are intended to uniformly color the skin, and it has been difficult to develop shades of color. In places such as eyebrows and eyelids, a color material is placed at the target location on the skin, and the skin can be colored at a desired concentration, and the color material is stably retained in the skin, and after a certain period of time. It needs to be excreted from the skin.

  An object of the present invention is to provide a microneedle device in which a coloring material can be easily arranged at a target location on the skin.

  In order to solve the above problems, the present invention provides a pressure-sensitive adhesive sheet having a base sheet, a pressure-sensitive adhesive layer laminated on the base sheet, a substrate having one surface in contact with the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet, A microneedle device having a plurality of protrusions including a color material formed on the side surface, and a part of the outer periphery of the substrate constitutes a part of the outer periphery of the microneedle device in plan view. In addition, the arrangement density of the protrusions increases toward a part of the outer periphery of the substrate.

  Further, the height of the projection may be 200 μm or less.

  In addition, the planar shape of the substrate is a spindle shape in which the short side direction is within 2 cm and the long side direction is within 4 cm, and the protrusions are densely formed at a part of the outer periphery in the long side direction of the substrate. You may.

  Further, the coloring material may be present on the surface of the protrusion.

  Further, the material of the microneedles may be a thermoplastic resin.

  Further, the material of the microneedle may be a biodegradable polysaccharide.

  Further, the coloring material may be a fluorescent substance.

  Further, a release sheet may be provided on a part of the surface of the adhesive layer that is not in contact with the microneedles.

  By using the microneedle device of the present invention, it is possible to easily arrange a coloring material at a target location on the skin.

FIG. 1 is a cross-sectional view of the microneedle device according to the embodiment. FIG. 2 is a plan view of the microneedle device according to the embodiment. FIG. 3 is a side view and a plan view showing an example of the microneedle device according to the embodiment. FIG. 4 is a schematic top view and a schematic cross-sectional view of the microneedle according to the embodiment. FIG. 5A is a diagram illustrating the method for manufacturing the microneedle device according to the embodiment. FIG. 5B is a diagram illustrating the method for manufacturing the microneedle device according to the embodiment. FIG. 5C is a diagram illustrating the method for manufacturing the microneedle device according to the embodiment. FIG. 5D is a diagram illustrating the method for manufacturing the microneedle device according to the embodiment. FIG. 5E is a diagram illustrating the method for manufacturing the microneedle device according to the embodiment. FIG. 5F is a diagram illustrating the method for manufacturing the microneedle device according to the embodiment.

  Embodiments of the present invention will be described in detail with reference to the drawings. First, a configuration and a material of the microneedle device of the embodiment will be described, and then a method of manufacturing the microneedle device will be described.

  FIG. 1 shows a cross-sectional view of the microneedle device according to the embodiment. FIG. 2 shows a plan view of the microneedle device according to the embodiment. FIG. 1 is a sectional view taken along line AA ′ in FIG. The microneedle device 1 according to the embodiment includes an adhesive sheet 20 and a microneedle 10, and the adhesive sheet 20 includes a base sheet 24 and an adhesive layer 22. The macroneedle 10 includes a substrate 14 having a first surface and a second surface, and a plurality of protrusions 12 formed on the first surface of the substrate 14, and the second surface of the substrate 14 is formed of an adhesive sheet. 20 is a structure in contact with the adhesive layer 22 of FIG. The microneedle device 1 can arrange the coloring material in the skin, for example, by sticking the adhesive layer 22 to the eye lid or the like and piercing the skin with the projection 12 containing the coloring material. The shape of the adhesive sheet 20 and the shape of the microneedles 10 do not need to match the shapes shown in FIGS. 1 and 2. The microneedle device 1 has a region where a part of the outer periphery of the adhesive layer 22 of the adhesive sheet 20 is outside the outer periphery of the microneedle 10. Thereby, when the microneedle device 1 is stuck to the eyelid, a part of the adhesive layer 22 is stuck to the eyelid, so that the microneedle device 1 can be stably and stably stuck to the skin. FIG. 3 is a side view and a plan view showing another example of the microneedle device according to the embodiment. As shown in FIG. 3, a C-shaped hole 23 may be provided at the center of the adhesive sheet 20. By providing the hole 23 in the center of the adhesive sheet 20, after attaching the microneedle device 1 to the skin, it is possible to make the lotion permeate through the hole 23 or to permeate a solution containing a coloring material. The effect can be enhanced. The shape of the hole 23 is not particularly limited, and examples thereof include a circle, an ellipse, a square, a polygon, and a spindle.

  The protrusion 12 includes a coloring material. In plan view, a part of the outer periphery of the substrate 14 coincides with a part of the outer periphery of the microneedle device 1, and the arrangement density of the protrusions 14 increases toward a part of the outer periphery of the substrate 14. Become. When the projection 12 containing the coloring material is pierced into the skin, the coloring material can be arranged in the skin. As the arrangement density of the projections 12 is higher, more coloring materials can be arranged on the skin. By increasing the arrangement density of the protrusions 12 toward a part of the outer periphery of the substrate 14, it is possible to provide the skin with shades of color after the microneedle device is attached. In particular, when the microneedle device 1 is attached to the eyelid, a part of the outer circumference where the arrangement density of the protrusions 12 on the substrate 14 is increased is attached to the eyelash side of the eyelid, Makeup effect can be enhanced. In addition, since a part of the outer periphery of the substrate 14 and a part of the outer periphery of the microneedle device 1 coincide with each other, a part of the outer periphery of the substrate 14 in which the arrangement density of the protrusions 12 including the coloring material is large, The puncture can be easily performed at a target portion of the skin such as the eyelash hairline of the eyelid.

  The color material may be present inside the projection 12, on the surface of the projection 12, or both.

  The shape of the projection 12 may be any shape as long as it is suitable for puncturing the skin, and may be appropriately designed. Specifically, the shape of the protruding portion may be a cone, a pyramid, a cylinder, a prism, a pencil shape (a body portion is a column shape, and a tip portion is a cone shape).

  As the coloring material, a substance generally used for cosmetics may be used, and examples thereof include dyes; organic pigments; natural pigments; inorganic pigments; By attaching the microneedle device 1 using a fluorescent dye such as Evans blue or rhodamine as a coloring material to the skin, the arrangement of the coloring material in the skin can be confirmed by analysis.

  4A and 4B are a schematic top view and a schematic cross-sectional view of the microneedle according to the embodiment. FIG. 4A is a schematic top view from the protrusion side of the microneedle, and FIG. It is a schematic cross section along the II 'line of a microneedle in (a). In the microneedle 10 of the embodiment, it is preferable that the size of the needle-shaped protrusion 12 has a fineness and a length suitable for forming a puncture hole in the skin. Specifically, the height H of the protrusion 12 shown in FIG. 4B is a vertical distance from the surface of the substrate 14 to the tip of the protrusion 12. It is desirable that the height H of the protrusion 12 be in the range of 30 μm or more and 200 μm or less. With such a needle height, the coloring material can be arranged in the skin, particularly in the stratum corneum. Since the stratum corneum is constantly newly produced by metabolism, the delivery in the stratum corneum is excreted from the body over time. Therefore, the coloring material can be eliminated by washing the skin or peeling the skin. By arranging the coloring material in the stratum corneum, it is possible to maintain the makeup state for a long period of time, and it is also possible to easily remove the color. If the height H of the protrusion 12 is larger than 200 μm, it is possible to arrange the coloring material in the skin, but it becomes difficult to remove the coloring material.

  The width D of the protrusion 12 is preferably in the range of 1 μm or more and 300 μm or less. It is preferable that the width D of the protrusion 12 is determined in consideration of the depth of the puncture hole formed when the protrusion 12 of the microneedle 10 is punctured within the above-described range, and the like. . The width D of the projection 12 is the length in the direction parallel to the surface of the substrate 14 that is the largest when the projection 12 is projected onto the surface of the substrate 14. For example, when the protrusion 12 has a conical shape, the diameter of the bottom surface of the protrusion 12 is the width D. When the protrusion 12 is a regular quadrangular pyramid, the diagonal line of the square on the bottom surface of the protrusion 12 has the width D. When the projection 12 is a column, the diameter of the bottom surface of the projection 12 is the width D. When the projection 12 is a square prism, the width D is the diagonal of the square on the bottom surface of the projection 12.

  The aspect ratio A of the projection 12 is preferably in the range of 1 or more and 10 or less. The aspect ratio A is defined by A = H / D using the height H and the width D of the protrusion 12. In the microneedle 10 according to the embodiment, when the projection 12 has a tip angle like a cone and penetrates the stratum corneum, the tip angle θ of the projection 12 is 5 ° or more and 30 ° or less, more preferably It is desirable that the angle be in the range of 10 ° or more and 20 ° or less. The tip angle θ indicates the tip angle (vertical angle) of the protrusion 12 in a cross section of the protrusion 12 perpendicular to the substrate 14.

  Referring to FIGS. 1 and 3 again, the planar shape of the substrate 14 is a spindle shape in which the short side direction is within 2 cm and the long side direction is within 4 cm. It is desirable that the parts are densely formed in a part of the outer periphery in the direction. By adopting such a shape, it is possible to adhere along the shape of the eyelid, so that the color of the coloring material can be darkened when the eyelashes of the eyelid grow, and as a result, the cosmetic effect Can be increased.

  The material forming the microneedles 10 in the embodiment is desirably a thermoplastic resin or a biodegradable polysaccharide. In the case of a thermoplastic resin, for example, polyethylene, polypropylene, polycarbonate, polyacetal, polystyrene, polymethyl methacrylate, cellulose acetate, polyethylene terephthalate, polyurethane, Teflon (registered trademark), polyvinyl chloride, polyvinylidene chloride, ethylene / vinyl acetate And polymers. Further, a biodegradable material is preferable. For example, polylactic acid, polybutylene succinate, polyε-caprolactone, polyβ-hydroxybutyric acid and the like can be mentioned. Further, a mixture of these thermoplastic resins may be used. By using the biodegradable resin, even if the protrusion 12 of the microneedle 10 is punctured into the skin and then damaged in the skin, it is possible to minimize the effect on the human body.

  When the material forming the microneedle 10 is a biodegradable polysaccharide, for example, dextran, dextrin, pectin, pullulan, chondroitin sulfate, alginate, chitosan, carboxymethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, methylcellulose, Ethyl cellulose and the like can be mentioned. Further, a mixture of these biodegradable polysaccharides may be used. By using the biodegradable polysaccharide, the protrusion 12 of the microneedle 10 can be dissolved in the skin after puncturing the skin. Therefore, the coloring material contained in the protrusion 12 can be efficiently introduced into the skin.

  When a thermoplastic resin is used as the material of the microneedles 10, it is desirable that the coloring material be present on the surface of the protrusion 12. Since the coloring material is present on the surface of the protrusion 12, the coloring material can be quickly introduced into the skin.

  In the dissolvable microneedle 10 in which the pierced needle-like projection 12 elutes into the skin, a coloring material can be contained inside the projection 12 or a coloring material can be provided on the surface of the projection 12.

  On the other hand, when coloring the coloring material to the skin using the microneedles 10, the coloring material may be applied to the target skin before or after the projection 12 is punctured into the skin. By doing so, it is possible to finely adjust the coloration on the skin and enhance the cosmetic effect.

  In the microneedle device 1 according to the embodiment, the substrate 14 may have flexibility. By using a flexible substrate, it is possible to appropriately puncture a flexible target such as a curved surface or a living skin.

  In the prescription using the microneedle device 1 of the embodiment, an applicator for fixing the insertion position and direction may be used.

  Next, a method for manufacturing the microneedle device according to the embodiment will be described with reference to FIGS. 5A to 5F.

<Process of making original plate>
First, as shown in FIG. 5A, an original 30 having a needle-like pattern 32 is prepared. As a method of manufacturing the original plate 30 that determines the shape and arrangement of the projections 12, a known manufacturing method may be used as appropriate according to the shape and arrangement of the projections 12. At this time, the original plate 30 may be formed by using a fine processing technique. As the fine processing technique, for example, a lithography method, a wet etching method, a dry etching method, a sand blast method, a laser processing method, a precision machining method, or the like is used. Is also good.

<Step of making intaglio>
Next, as shown in FIG. 5B, an intaglio 40 is produced based on the original 30. The intaglio 40 is produced by a transfer method in which the intaglio material 42 is peeled off after the intaglio material 42 is placed on the original 30 as shown in the left diagram of FIG. 5B. As the intaglio material 42, a silicone resin is desirable. The type of silicone may be arbitrarily selected as long as it is suitable for intaglio formation. As shown in the right view of FIG. 5B, the intaglio 40 thus produced has a pattern 44 corresponding to the projection 12 of the microneedle 10 and having a shape inverted from the projection 12.

<Process for manufacturing microneedles>
Next, as shown in the left diagram of FIG. 5C, the material 16 of the microneedle 10 is put into the intaglio 40, the pattern is transferred, and the material 16 is peeled off, thereby obtaining the microneedle 10 shown in the right diagram of FIG. 5C. . When the material 16 of the microneedle 10 is a thermoplastic resin, the thermoplastic resin is put into the intaglio 40, heated and melted at a temperature equal to or higher than the melting point of the thermoplastic resin, pressed, and cooled and hardened. The pressing pressure needs to be lower than the force at which the intaglio plate 40 is not broken, and is preferably 1 MPa or less. The cooling may be performed while the press is performed, or the cooling may be performed after the press is opened. The cooling may be performed by any method such as a contact method and a non-contact method. When the material 16 of the microneedle 10 is a biodegradable polysaccharide, a solution in which the material or the material and the coloring material are dissolved or dispersed is prepared. The microneedle 10 can be obtained by pouring the solution into the intaglio 40, drying and removing the solvent to cure the cured product, and then removing the cured product from the intaglio 40. When the solution in which the material 16 is dissolved is poured into the intaglio 40 under reduced pressure, the material 16 can be efficiently supplied to the pattern 44.

<Step of adjusting the external shape of the microneedle>
As shown in FIG. 5D, the outer shape of the obtained microneedle 10 can be processed as necessary. The processing method may be appropriately selected, for example, punching and the like.

<Process of bonding microneedle and adhesive sheet>
Next, as shown in FIG. 5E, the microneedle device 1 is obtained by bonding the microneedles 10 and the adhesive sheet 20 together. In addition, as shown in FIG. 5F, in order to protect a part of the surface of the adhesive layer 22 that is not in contact with the microneedles 10, a release sheet 50 may be attached to the part. By laminating the release sheet 50, the handling of the microneedle device 1 can be facilitated.

<Process for containing coloring material>
The method of placing the coloring material on the surface of the protrusion 12 may be appropriately selected. For example, a method in which the protrusion 12 is immersed in a solution in which the coloring material is dissolved or dispersed, and the solvent is dried; A method in which the solution thus applied is applied to the protrusions 12 by spraying, and the like. The step of placing the coloring material on the surface of the protrusion 12 may be performed before or after the step of adjusting the outer shape of the microneedle 10.

  Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

(Example 1)
A microneedle device was manufactured according to the following procedure.
(1) In a 30 mm × 30 mm region at the center of the surface of 50 mm × 50 mm × 5 mm brass, a circular cone having a bottom surface of 50 μm and a height of 150 μm was formed in the following arrangement by cutting.
・ The first row has a 50 μm pitch. ・ The nth row has a 50 + 5 (n−1) μm pitch.
(2) Release the original plate of (1), drop silicone resin (Sylpot 184, Dow Corning Toray) on the surface where the cone is formed, and heat on a hot plate at 100 ° C for 30 minutes. The silicone resin was cured.
(3) The cured silicone resin was peeled from the master.
(4) The peeled silicone resin was placed in an oven at 200 ° C. for 1 hour, and the unreacted silicone resin was completely reacted to obtain an intaglio.
(5) A 5% aqueous solution of hydroxypropylcellulose containing 1% by weight of Evans blue is dropped on the intaglio obtained in (4), and left standing for 4 days in an environment of 25 ° C. and 65% RH to remove water. Evaporated.
(6) The cured product dried and cured was peeled from the intaglio plate to obtain a microneedle.
(7) In the microneedle obtained in (6), a 1 mm outer portion of the array of protrusions corresponding to the first row of the original plate was cut off.
(8) A part of the outer periphery of the cut end of the microneedle obtained in (7) and the adhesive sheet (tape 9835, 3M) in the microneedle and a part of the outer periphery of the adhesive sheet coincide with each other. To obtain a microneedle device.

(Comparative Example 1)
A microneedle device was produced in the same manner as in Example 1 except that an aqueous solution of hydroxypropylcellulose containing no Evans blue was used in (5) of Example 1.

(Comparative Example 2)
In (8) of Example 1, the same as Example 1 except that the microneedles and the pressure-sensitive adhesive sheet were bonded so that the outer circumference of the pressure-sensitive adhesive sheet protruded 3 mm outside the outer circumference of the cut end of the microneedle. A microneedle device was produced by the method.

(result)
After attaching the microneedle devices of Example 1 and Comparative Examples 1 and 2 to the shaved mouse skin for 2 hours, the microneedle device was peeled off, and the coloration of the mouse skin surface was measured using a microscope. Observed. As a result, in Example 1, the region where the density of the protrusions was higher in the attached microneedle device was stained darker blue. The area where the adhesive sheet directly hit the skin was not stained. When the state of the stained skin was observed over time, no stained blue color was observed after one week.

  In Comparative Example 1, the skin was not stained at all. In Comparative Example 2, the area where the pressure-sensitive adhesive sheet protruding 3 mm outside the outer periphery of the end of the microneedle directly hit the skin was not stained. Therefore, in the microneedle device according to Comparative Example 2, it is possible to easily puncture a part of the outer periphery where the arrangement density of the protrusions including the coloring material is large into a target portion of the skin such as the eyelash line of the eyelid. It turned out that it could not be said.

  The microneedle device of the present invention can be used not only in the fields of cosmetics and beauty, but also in various fields that require fine microneedles. For example, it can be expected to be applied as a microneedle device used for MEMS devices, optical members, sample jigs, drug discovery, medical applications, and the like.

DESCRIPTION OF SYMBOLS 1 ... Microneedle device 10 ... Microneedle 12 ... Protrusion part 14 ... Substrate 16 ... Microneedle material 20 ... Adhesive sheet 22 ... Adhesive layer 23 ... Hole 24 ... Base sheet 30 ... Original 32 ... Needle pattern 40 ... Intaglio 42 ... Intaglio material 44... Pattern 50 with inverted protrusions 50... Release sheet

Claims (8)

Base sheet, and an adhesive sheet having an adhesive layer laminated on the base sheet,
A substrate having one surface in contact with the adhesive layer of the adhesive sheet, a microneedle having a plurality of protrusions including a coloring material formed on the other surface of the substrate,
A microneedle device comprising:
A microneedle device in which a part of the outer periphery of the substrate constitutes a part of the outer periphery of the microneedle device in a plan view, and the arrangement density of the protrusions increases toward a part of the outer periphery of the substrate; .   The microneedle device according to claim 1, wherein the height of the protrusion is 200 μm or less. The planar shape of the substrate is a spindle shape in which the short side direction is within 2 cm and the long side direction is within 4 cm,
3. The microneedle device according to claim 1, wherein the protrusions are densely formed at a portion forming a part of an outer periphery of the substrate in the long side direction. 4.   4. The microneedle device according to claim 1, wherein the coloring material is present on a surface of the protrusion. 5.   The microneedle device according to claim 4, wherein the material of the microneedle is a thermoplastic resin.   The microneedle device according to any one of claims 1 to 4, wherein a material of the microneedle is a biodegradable polysaccharide.   The microneedle device according to claim 1, wherein the coloring material is a fluorescent substance.   The microneedle device according to claim 1, further comprising a release sheet on a part of the surface of the adhesive layer that is not in contact with the microneedle.

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