JP7335061B2 - Beauty method using microneedle sheet - Google Patents

Description

The present invention relates to a microneedle sheet with a plurality of microneedles that can be used for cosmetic treatment of keratinous substances such as skin and lips.

The stratum corneum (SC) constitutes the main barrier to exogenous substances, including low molecular weight materials. In general, exogenous substances that penetrate the skin must diffuse through the highly organized intercellular lipid bilayer of the stratum corneum. This intercellular micropathway, which is lipophilic, is the major pathway by which exogenous substances cross the SC barrier by passive diffusion following a concentration gradient between the delivery vehicle and the SC. Some exogenous substances have difficulty penetrating into the skin.

Injections using conventional needles can be performed to deliver exogenous substances deeper into the skin. However, such injections cause pain and need to be performed by a professional such as a doctor. Therefore, injections using conventional needles are not common for cosmetic purposes.

The idea of using a microstructured device with multiple microneedles to break the stratum corneum (SC) barrier was first proposed in the 1970s. The manufacture of microneedle arrays has been described in the art, for example in WO2008/139786, WO2009/040548, WO2015/147040 and WO2016/076442. Microneedles have the advantage of potentially penetrating the SC without the pain caused by the use of conventional needles for injection, and of being able to be self-administered.

Generally, microneedles are aligned on a substrate sheet to form a microneedle sheet. The microneedle sheet is applied for some time onto a keratinous material such as skin so that the microneedles can be dissolved or disintegrated within the keratinous material by moisture or water inside the keratinous material.

However, even after the microneedles dissolve or disintegrate, the base sheet may remain and create an unpleasant feel.

WO2008/139786 WO2009/040548 WO2015/147040 WO2016/076442 U.S. Patent No. 6,219,574 Canadian Patent Application No. 2,226,718 U.S. Patent No. 6,652,478

ISO standard 1 1357-3

An object of the present invention is to provide a cosmetic method using a microneedle sheet having microneedles on a base sheet, wherein the base sheet can be quickly dissolved or disintegrated. That is.

The above object is a cosmetic method for keratinous substances such as skin or lips, comprising:
applying a microneedle sheet comprising a base sheet and a plurality of microneedles on the base sheet over the keratinous material, the base sheet comprising at least one water-soluble or water-dispersible polymer; process and
applying a porous sheet containing at least one composite fiber over the microneedle sheet, wherein the porous sheet contains water.

The microneedles may have a height of 50-1000 microns, preferably 100-750 microns, more preferably 150-500 microns.

The microneedles may be in the shape of cones.

The base of the cone of microneedles may have a diameter of 50-350 microns, preferably 100-300 microns, more preferably 150-250 microns.

The ratio of (cone height)/(cone base diameter) of the microneedles may be 1 or more, preferably 1.5 or more, more preferably 2.0 or more.

Water-soluble or water-dispersible polymers include hyaluronic acid, monosaccharides, disaccharides, oligosaccharides, polysaccharides, dextrin, dextran, polyethylene glycol, polyvinyl alcohol, poly(methyl vinyl ether/maleic anhydride), polyvinylpyrrolidone, poly(methyl/ vinyl ether/maleic acid) (PMVE/MA) and its esters, poly(methyl/vinyl ether/maleic anhydride) (PMVE/MAH), and mixtures thereof.

The water-soluble or water-dispersible polymer may have a molecular weight of 10,000-200,000 Daltons, preferably 30,000-150,000 Daltons, more preferably 50,000-100,000 Daltons.

Bicomponent fibers may comprise a fiber body comprising at least two polymers, preferably two non-polar polymers, more preferably two polyolefin polymers.

Bicomponent fibers may have at least one coating.

The coating may comprise at least one polymer, preferably one hydrophilic polymer, more preferably at least one hydrophilic acrylic polymer.

The porous sheet may be a woven or non-woven fabric, preferably a non-woven fabric, more preferably a non-woven fabric prepared by a thermal bonding method.

At least one of the microneedles may contain at least one cosmetically active ingredient.

The present invention also provides
a microneedle sheet comprising a base sheet and a plurality of microneedles on the base sheet, the base sheet comprising at least one water-soluble or water-dispersible polymer;
It also relates to a kit comprising a porous sheet comprising at least one composite fiber, preferably further comprising water, more preferably packaged together with water in a container.

The present invention also provides a method for dissolving a base sheet of a microneedle sheet comprising a base sheet and a plurality of microneedles on the base sheet, comprising:
the base sheet comprises a base sheet containing at least one water-soluble or water-dispersible polymer;
It also relates to a method, wherein said method comprises applying a porous sheet containing at least one bicomponent fiber and containing water over said base sheet.

The present invention is also the use of a porous sheet comprising at least one composite fiber for dissolving a substrate sheet and a microneedle sheet comprising a plurality of microneedles on the substrate sheet. hand,
The porous sheet contains water,
It also relates to the use, wherein said base sheet comprises at least one water-soluble or water-dispersible polymer.

As a result of intensive investigation, the inventors have found a cosmetic product using a microneedle sheet having microneedles on a base sheet, the base sheet being capable of rapidly dissolving or disintegrating. We have found that it is possible to provide a method.

Accordingly, one aspect of the present invention is a cosmetic method for keratinous material, such as skin or lips, comprising:
applying a microneedle sheet comprising a base sheet and a plurality of microneedles on the base sheet over the keratinous material, the base sheet comprising at least one water-soluble or water-dispersible polymer; process and
applying a porous sheet containing at least one type of composite fiber onto the microneedle sheet, wherein the porous sheet contains water.

According to the invention, the base sheet can be rapidly dissolved or disintegrated. In other words, the base sheet can dissolve or disintegrate in a short period of time. Therefore, the base sheet, which can provide an unpleasant touch, can be easily removed and does not remain on the keratin material for a long period of time.

Therefore, the cosmetic method according to the invention can be carried out in a relatively short period of time.

Since microneedles do not cause any pain, the cosmetic method according to the present invention can provide a cosmetic treatment without pain.

The present invention is advantageous for cosmetic or non-therapeutic treatments.

The cosmetic method, kit, etc. according to the present invention will be described in detail below.

[Beauty method]
The cosmetic method according to the invention for keratinous substances such as skin or lips comprises:
applying a microneedle sheet comprising a base sheet and a plurality of microneedles on the base sheet over the keratinous material, the base sheet comprising at least one water-soluble or water-dispersible polymer; process and
applying a porous sheet comprising at least one composite fiber over said microneedle sheet, said porous sheet comprising water.

The cosmetic method according to the invention may be intended for the cosmetic treatment of keratinous substances such as skin or lips, preferably skin, more preferably facial skin.

The cosmetic method according to the invention is used to improve the aesthetic appearance of keratinous materials, for example by reducing the appearance of wrinkles or by supplying the keratinous materials with any cosmetic active ingredients, if present. sell.

A reduction in the amount of matrix in the skin, such as the epidermis, tends to result in a reduction in skin thickness and deterioration in skin elasticity, leading to wrinkle formation. Microneedles can increase the amount of matrix in the skin and cause an increase in skin elasticity, which results in less wrinkles on the skin.

If the microneedle is swellable, especially at its distal end portion, it can swell within the skin to further increase the volume of the microneedle with its absorption of, for example, moisture within the skin. . Such volume expansion below the skin surface at the wrinkle site can effectively push wrinkles from within the skin, making them shallower and wider. In this way, wrinkles can be reduced or made less noticeable.

Therefore, it is preferable that the cosmetic method according to the present invention includes a step of pressing the microneedle sheet onto the keratinous substance to ensure that the microneedles of the microneedle sheet are inserted into the keratinous substance such as skin.

In one particular embodiment, the cosmetic method according to the invention can be used for applying semi-permanent or permanent cosmetic treatments to keratinous substances such as skin.

The microneedle sheet and porous sheet used for the cosmetic method according to the present invention are described in detail below.

{Microneedle sheet}
The microneedle sheet used for the method according to the present invention comprises a base sheet and a plurality of microneedles on the base sheet, the base sheet comprising at least one water-soluble or water-dispersible polymer. .

The microneedle sheet used for the present invention may be a cosmetic device, preferably a cosmetic device for keratinous substances, more preferably a cosmetic device for skin, especially facial skin as well as lips.

(microneedle)
A microneedle sheet used for the present invention comprises a plurality of microneedles.

Microneedles are present on the surface of the base sheet. The microneedles may be present on 50% or more, preferably 70% or more, more preferably 90% or more of the surface of the base sheet.

Preferably, the microneedles are present on one of the surfaces of the base sheet.

It is preferred that the microneedles of the microneedle sheet used for the present invention are designed to penetrate or enter the stratum corneum of the skin, especially the skin of the face as well as the lips.

Microneedles can be of any size and shape suitable for puncturing the stratum corneum. It may be preferred that the microneedles are designed to traverse through the stratum corneum. Microneedles may be capable of creating openings in the stratum corneum.

If desired, the height of the microneedles may be altered to allow penetration into the epidermis and/or dermis of the skin, preferably into the upper dermis, more preferably into the lower dermis.

The shape of the microneedle is not limited as long as the shape is "needle". It will be apparent to those skilled in the art that the microneedles of the present invention can take any reasonable shape including, but not limited to, cone-shaped, rod-shaped and/or pillar-shaped. Thus, the microneedles may have the same diameter at the tip as the bottom, or may taper in diameter from the bottom to the tip.

For example, the shape of the microneedles may be in the form of triangular pyramids, square pyramids or pentagonal pyramids. Alternatively, the microneedles may preferably be in the form of cylinders with tips that may be formed by diagonally cutting the cylinder.

Thus, reference is made to "microneedles" as the type of microprotrusions or microprotrusions utilized. It will be appreciated by those skilled in the art that in many cases the same inventive principles apply to the use of other microprotrusions or microprotrusions to penetrate the skin. Other microprotrusions or microprotrusions include, for example, microblades as described in U.S. Pat. A needle may be included.

The height or length of the microneedles of the microneedle sheet used for the present invention may be 50-1000 microns, preferably 100-750 microns, more preferably 150-500 microns.

According to one embodiment of the invention, the microneedles are in the form of cones.

A cone may include a distal end, such as a tip and a base. The shape of the bottom surface may be circular or oval.

The height or length of the cones of microneedles of the microneedle sheet used for the present invention may be 50-1000 microns, preferably 100-750 microns, more preferably 150-500 microns.

The bottom surface of the cones of microneedles of the microneedle sheet used for the present invention may have a diameter or width of 50-350 microns, preferably 100-300 microns, more preferably 150-250 microns. When the base of the cones of the microneedles of the microneedle sheet used for the present invention is in the shape of an ellipse or ellipse, the length or width of the main axis of the ellipse is 50-350 microns, preferably 100 microns. It may be ~300 microns, more preferably 150-250 microns.

The microneedles may have an aspect ratio (base length/width) of at least about 3:1, at least about 2:1, or at least about 1:1. The ratio of (cone height)/(cone base diameter) of the microneedles may be 1 or more, preferably 1.5 or more, more preferably 2.0 or more.

Preferably, the microneedles are fractured under the force when an insertion pressure of less than 50.0 N/cm ² , such as less than 20.0 N/cm ² , such as less than 10 N/cm ² is applied to the microneedles along the length of the microneedles. do not.

It is also preferred that the microneedle sheet used for the present invention, especially the microneedles of the microneedle sheet, has a Young's modulus of 50 N/mm or more, preferably 55 N/mm or more, more preferably 60 N/mm or more.

It may be preferred that the microneedles are able to penetrate into keratinous material such as skin or lips to a depth of 200 microns or less, preferably 180 microns or less, more preferably 160 microns or less.

Microneedles may be soluble or non-soluble. It is preferred that the microneedles are soluble.

"Dissolvable microneedles" means that the microneedles can break or disintegrate inside keratinous materials such as the skin or lips, for example by natural wetting factors or external moisture.

The microneedles of the microneedle sheet used for the present invention may contain at least one water-soluble or water-dispersible polymer. Here, the terms "water-soluble" and "water-dispersible" mean soluble and dispersible, respectively, when in contact with water. A single water-soluble or water-dispersible polymer may be used. Two or more water-soluble or water-dispersible polymers can be used in combination.

It is preferred that the water-soluble or water-dispersible polymer is soluble or dispersible in the skin or lips. Thus, in one embodiment of the invention, the water-soluble or water-dispersible polymer can be dissolved or dispersed after being inserted into keratinous material such as skin or lips. Due to the solubility or dispersibility of the polymer, the microneedles of the microneedle sheet used for the present invention can effectively release the agent when the agent is present in the microneedles. Optional external water combined with application of the microneedle sheet can be used to facilitate dissolution or dispersion of the microneedles.

It is preferred that the water-soluble or water-dispersible polymer is soluble within the surface layers of keratinous materials such as the skin or lips.

Water-soluble or water-dispersible polymers include hyaluronic acid (especially low molecular weight hyaluronic acid), monosaccharides, disaccharides, oligosaccharides, polysaccharides (including derivatives thereof such as hydroxymethylcellulose), dextrins, dextrans, polyethylene glycols, polyvinyl alcohols, Poly(methyl vinyl ether/maleic anhydride), polyvinylpyrrolidone, poly(methyl/vinyl ether/maleic acid) (PMVE/MA) and its esters, poly(methyl/vinyl ether/maleic anhydride) (PMVE/MAH), and these You can choose from mixtures.

The water-soluble or water-dispersible polymer may have a molecular weight of 10,000-200,000 Daltons, preferably 30,000-150,000 Daltons, more preferably 50,000-100,000 Daltons.

Low molecular weight hyaluronic acid may have a molecular weight of 100 kDa or less, preferably 70 kDa or less, more preferably 50 kDa or less.

Polyvinylpyrrolidone may have a molecular weight between 1 kDa and 300 kDa, preferably between 5 kDa and 200 kDa, more preferably between 7 kDa and 100 kDa.

Poly(methyl/vinyl ether/maleic acid) (PMVE/MA) and its esters, and poly(methyl/vinyl ether/maleic anhydride) (PMVE/MAH) are known as Gantrez-type polymers.

The amount of water-soluble or water-dispersible polymer in the microneedles of the microneedle sheet used for the present invention (solid basis) is 50% by mass or more, preferably 60% by mass, based on the total mass of the microneedles. or more, more preferably 70% by mass or more. The amount of water-soluble or water-dispersible polymer in the microneedles of the microneedle sheet used for the present invention (solid basis) is 100% by mass or less, preferably 90% by mass, relative to the total mass of the microneedles. 80% by mass or less, more preferably 80% by mass or less. Therefore, the amount of water-soluble or water-dispersible polymer in the microneedles of the microneedle sheet used for the present invention (solid basis) is 50% by mass to 100% by mass with respect to the total mass of the microneedles, It may be preferably 60% to 90% by mass, more preferably 70% to 80% by mass.

At least one microneedle of the microneedle sheet used for the present invention is swellable, more preferably water-swellable, even more preferably swellable in keratinous substances such as skin or lips. It may be possible to include seed material. Said material may be a polymer that is swellable, more preferably water-swellable, even more preferably swellable within the keratinous material. Here, the term "water-swellable" means swellable when in contact with water. The above-mentioned swellable material or polymer is more preferably at least 10-fold larger in 1 hour in vitro incubation in saline or phosphate buffered saline, preferably at least 20-fold larger in 1 hour incubation, more preferably Highly swellable, such that the can swell at least 30-fold in 1 hour of incubation, even more preferably at least 40-fold in 1 hour of incubation, and most preferably about 45-55-fold in 1 hour of incubation can have

At least the distal end portion of the microneedle swells at least twice upon insertion into the keratinous material, more preferably within less than 1 hour after insertion into the keratinous material, and even more preferably within 24 hours. may be preferred.

Said swellable material, preferably said swellable polymer, has a high viscoelasticity such that it can form a gel after in vitro incubation in saline or phosphate buffered saline. sell. In a dynamic frequency sweep test using a rheometer, the gel exhibits a high elastic modulus G', a high viscous modulus G'', a tangent (δ) of less than 1 (tangent (δ) = G''/G') and high consistency G*(G* ² =G' ² +G'' ² ).

In one embodiment, the swellable material, preferably the swellable polymer, is not water soluble or water dispersible.

In another embodiment, the swellable material, preferably the swellable polymer, may be a hydrogel-forming polymer.

The above swelling polymers are high molecular weight hyaluronic acid, crosslinked hyaluronic acid, crosslinked polyethylene glycol, polyethylene glycol crosslinked polylactic or polyglycolic acid or poly-lactic-co-glycolic acid or polydioxanone, poly(styrene)-block-poly( acrylic acid), polyethylene glycol crosslinked PMVE/MA, crosslinked polyvinylpyrrolidone, sodium starch glycolate; cellulose; natural and synthetic gums; alginates; sodium polyacrylate PEG crosslinked poly(methyl/vinyl ether/maleic acid) (PMVE/MA) and It can be selected from esters thereof, PEG-crosslinked poly(methyl/vinyl ether/maleic anhydride) (PMVE/MAH) and esters thereof, and mixtures thereof.

High molecular weight hyaluronic acid may have a molecular weight above 500 kDa, preferably above 1000 kDa, more preferably above 2100 kDa, and preferably below 10000 kDa.

Unless otherwise specified, molecular weights herein refer to number average molecular weights.

Poly(methyl/vinyl ether/maleic acid) (PMVE/MA) and its esters, and poly(methyl/vinyl ether/maleic anhydride) (PMVE/MAH) are known as Gantrez-type polymers.

The amount of swelling material in the microneedles of the microneedle sheet used for the present invention (solid basis) is 1% by mass or more, preferably 5% by mass or more, more preferably 5% by mass or more, relative to the total mass of the microneedles. may be 10% by mass or more. The amount of swelling material in the microneedles of the microneedle sheet used for the present invention (solid basis) is 30% by mass or less, preferably 25% by mass or less, more preferably 25% by mass or less, relative to the total mass of the microneedles. may be 20% by mass or less. Therefore, the amount of swellable material in the microneedles of the microneedle sheet used for the present invention (solid basis) is 1% to 30% by mass, preferably 5% by mass, relative to the total mass of the microneedles. % to 25% by weight, more preferably 10% to 20% by weight.

When the microneedles of the microneedle sheet used for the present invention comprise at least one swellable material, preferably at least one swellable polymer, the microneedles are made of keratinous material, preferably skin, or more. Preferably, it may be swellable so that the aesthetic appearance of facial skin can be improved by reducing the appearance of wrinkles.

In other words, if the microneedle is swellable, it can swell within the skin to further increase the volume of the microneedle with its absorption of, for example, moisture within the skin. Such volume expansion below the skin surface at the wrinkle site can effectively push wrinkles from within the skin, making them shallower and wider. In this way, wrinkles can be reduced or made less noticeable.

The tip separation distance between each of the individual microneedles on the substrate sheet is such that it has a sufficiently short separation distance to ensure penetration of the skin or lips by the microneedles while at the same time providing a high transdermal transport rate. can be changed.

In one embodiment, the range of tip separation distance between microneedles can be in the range of 10-1000 μm, such as 30-800 μm, or 50-600 μm. This is a compromise to be achieved between efficient penetration of the stratum corneum by as many microneedles as possible and the necessary room for possible swelling of the microneedles if they are swellable. points.

In one embodiment, the density of microneedles may be 100-2000 microneedles/cm ² , preferably 200-1000 microneedles/cm ² , even more preferably 200-500 microneedles/cm ² .

(beauty active ingredient)
According to one embodiment, at least one of the microneedles of the microneedle sheet used for the present invention may contain at least one cosmetically active ingredient. A single cosmetic active ingredient may be used. Two or more cosmetic active ingredients can be used in combination.

The type of cosmetic active ingredient is not limited. For example, anti-aging agents may be used as cosmetic active ingredients.

Examples of anti-aging agents include antioxidants, moisturizers, free radical scavengers, keratolytic agents, vitamins, anti-elastase and anti-collagenase agents, protides, fatty acid derivatives, steroids, trace elements, bleaching agents, algae and plankton. Mention may be made of extracts, enzymes and coenzymes, flavonoids and ceramides, and mixtures thereof.

The amount of the cosmetic active ingredient in the microneedles of the microneedle sheet used for the present invention is not limited, and is 0.01% to 10% by mass, preferably 0.05% to 5% by mass, based on the total mass of the microneedles. % by weight, more preferably between 0.1% and 1% by weight.

It is also possible that the amount of cosmetically active ingredient in the microneedles of the microneedle sheet used for the present invention is less than 0.01% by mass relative to the total mass of the microneedles. In one embodiment, the microneedles of the microneedle sheet according to the invention may be completely free of cosmetically active ingredients.

(base material sheet)
A microneedle sheet according to the present invention comprises a base sheet on which microneedles are present or placed.

The base sheet of the microneedle sheet used for the present invention is soluble in water or disintegratable in water.

The base sheet of the microneedle sheet used for the present invention contains at least one water-soluble or water-dispersible polymer as described above. In other words, the above description of the water-soluble or water-dispersible polymer that may be included in the microneedles of the microneedle sheet can be applied to the water-soluble or water-dispersible polymer included in the base sheet.

For example, the amount of water-soluble or water-dispersible polymer in the base sheet of the microneedle sheet used for the present invention (solid basis) is preferably 50% by mass or more, based on the total weight of the base sheet. may be 60% by mass or more, more preferably 70% by mass or more. The amount of water-soluble or water-dispersible polymer in the base sheet of the microneedle sheet used for the present invention (solid basis) is 100% by mass or less, preferably 90% by mass, based on the total mass of the base sheet. It may be 80% by mass or less, more preferably 80% by mass or less. Therefore, the amount of water-soluble or water-dispersible polymer in the base sheet of the microneedle sheet used for the present invention (solid basis) is 50% by mass to 100% by mass with respect to the total mass of the base sheet. %, preferably 60% to 90% by weight, more preferably 70% to 80% by weight.

The base sheet and microneedles may be separate or integrated.

For example, the base sheet and microneedles can contain at least one common water-soluble or water-dispersible polymer. Thus, in one embodiment, the base sheet and microneedles can be a single element comprising at least one common water-soluble or water-dispersible polymer. Preferably, the single elements can be prepared using the same water-soluble or water-dispersible polymer.

On the other hand, the substrate sheet may be different or separate from the microneedles. For example, the base sheet and microneedles may be made from different materials. In this case, the substrate sheet may be chosen from, for example, masks, wipes, patches, and generally all kinds of porous substrate sheets. Preferably, these base sheets have an oval structure, ie, have a thickness that is less than the dimension of the plane in which they are defined.

The base sheet may be cut into patches, discs, masks, towels, gloves, pre-cut rolls, or any other form suitable for cosmetic use.

(preparation)
There is no limitation as to how the microneedle sheets used for the present invention are prepared. Microneedle sheets used for the present invention can be prepared based on conventional techniques such as molding, 3D printing and Droplet-born Air Blowing.

Microneedle sheets used for the present invention can be prepared, for example, by a method comprising molding a composition comprising at least one water-soluble or water-dispersible polymer as described above.

In one embodiment, the microneedle sheet used for the present invention is
(a) providing a mold having cavities corresponding to the microneedle negatives;
(b) filling the cavity with a composition comprising at least one water-soluble or water-dispersible polymer as described above;
(c) solidifying the composition to form microneedles, for example by drying at room temperature (optionally with heating) for a period of time such as several hours;
(d) removing the microneedle sheet from the mold.

Molds can be made from organic materials such as polyamides and silicones, and inorganic materials such as aluminum and iron.

At least one evaporative liquid component may be included in the composition, if necessary, to enhance the fluidity of the composition. Non-limiting examples of evaporable liquid components may preferably be water and alcohols such as ethanol.

The amount of evaporable liquid component may be 10% or more, preferably 20% or more, more preferably 30% or more by weight relative to the total weight of the composition. The amount of evaporable liquid component may be 98% or less, preferably 95% or less, more preferably 90% or less, relative to the total weight of the composition. Therefore, the amount of evaporable liquid component is 10% to 98% by weight, preferably 20% to 95% by weight, more preferably 30% to 90% by weight, relative to the total weight of the composition. good.

The amount of water-soluble or water-dispersible polymer in the above composition, which is preferably capable of flowing, more preferably in liquid form, is from 2% to 90% by weight relative to the total weight of the composition. % by weight, preferably 5% to 50% by weight, more preferably 5% to 30% by weight.

If desired, the compositions described above may comprise at least one additional polymer, such as the swelling polymers described above, and/or at least one cosmetically active ingredient described above.

The shape of the microneedle sheet used for the present invention is not limited, it can be any shape, such as the shape of the lips, or a shape suitable for application under the eyes, depending on the target to which the microneedle sheet is applied. It's okay.

{Porous sheet}
The porous sheet used for the cosmetic method according to the invention contains at least one bicomponent fiber.

Composite fibers comprise a body made from at least two polymeric materials. A body can include a core and a sheath. In one embodiment, the core comprises at least one polymeric material and the sheath comprises at least one polymeric material.

In one preferred embodiment, the bicomponent fibers are bicomponent fibers. Therefore, it is preferred that the body comprises two polymers, each forming a core and a sheath. In one embodiment, the body polymer in the cross-section of the fiber is arranged as a side-by-side sheath/core. In one embodiment, the polymers of the body in the cross-section of the fiber are arranged as a co-centered or non-centered sheath/core.

In one preferred embodiment, the body comprises a core with a higher melting point (melting temperature) and a sheath with a lower melting point (melting temperature).

Melting point, within the meaning of the present invention, corresponds to the temperature of the highest endothermic peak observed by thermal analysis (DSC) according to ISO 1 1357-3. Melting points may be measured using a differential scanning calorimeter (DSC), for example the calorimeter sold by TA Instruments under the designation "MDSC 2920".

In one embodiment, the melting point of the core of the body is greater than 150°C. In one embodiment, the melting point of the core of the body is greater than 230°C. In one embodiment, the melting point of the core of the body is in the range of 150°C to 300°C. In one embodiment, the melting point of the core of the body is in the range of 230°C to 300°C.

In one embodiment, the melting point of the sheath of the body is less than 230°C. In one embodiment, the melting point of the sheath of the body is less than 150°C. In one embodiment, the melting point of the sheath of the body is in the range of 100°C to 230°C. In one embodiment, the melting point of the sheath of the body is in the range of 100°C to 150°C.

In a particular preferred embodiment, said composite fiber comprises a body comprising a core formed from a first polymer and a sheath formed from a second polymer, said first polymer comprising a second It has a higher melting point than the polymer.

Non-limiting examples of polymers that can be used as one type of polymer for the body are polyesters such as polylactic acid, derivatives of polyesters, polyamides such as nylon 6 and nylon 66, polyolefins such as polypropylene and polyethylene, polystyrene, and any mixture thereof.

In one embodiment, non-limiting examples of polymers that can be used as one type of polymer for the body include low density polyethylene (LDPE), polypropylene (PP), high density polyethylene (HDPE), ultra high molecular weight polyethylene. (UHMW), polypropylene (PP), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyester and polyethersulfone (PES), and any mixtures thereof.

In one embodiment, the core of the body is selected among polypropylene (PP) and the sheath of the body is selected among polyethylene (PE), said polypropylene having a higher melting point than said polyethylene.

Some common examples of combinations of two fibers are given below:
- polyester core (melting point 250°C) and copolyester sheath (melting point 110°C-220°C),
- polyester core (melting point 250°C) and polyethylene sheath (melting point 130°C),
- Polypropylene core (melting point 175°C) and polyethylene sheath (melting point 130°C).

In one preferred embodiment, the bicomponent fiber may comprise a fiber body comprising at least two polymers, more preferably two non-polar polymers, even more preferably two polyolefin polymers such as polyethylene and polypropylene.

In one preferred embodiment, the bicomponent fiber has at least one coating.

In one embodiment, the coating comprises at least one polymer. Preferably, the polymer in the coating comprises a hydrophilic polymer, more preferably at least one hydrophilic acrylic polymer. The hydrophilic polymer can preferably be selected from the group consisting of any commercially available hydrophilic polymer. Non-limiting examples of such polymers can be selected from acrylic acid, methacrylic acid, glutamic acid, β-carboxyethyl acrylate, maleic acid, monoesters of maleic acid, and the like. More preferably, said hydrophilic polymer is an acrylic or acrylate polymer.

Acrylic or acrylate polymers containing carboxyl groups are commercially available. In one particular embodiment, said hydrophilic polymer is poly(acrylic acid). For example, poly(acrylic acid) is available from Polycryl AG, Bohler, Postfach, CH-6221 Rickenbach, Switzerland (trade name: Polycryl); Stockhausen, 2401 Doyle Street, Greensboro, N.C., 27406- 2911; and BFGoodrich, Four Coliseum Centre, 2730 West Tyvola Rd., Charlotte, N.C. 28217-4578 (trade name: Carbopol).

Polymers for bicomponent fibers (either body or coating) refer to polymers made based on a single monomer or based on two or more monomers. The term polymer is therefore broad in the sense of the invention and includes homopolymers and copolymers unless otherwise specified. Copolymers refer to random or alternating copolymers without limitation except that they are suitable for the present invention.

Polymers for bicomponent fibers may be linear or branched.

In one particular embodiment, the composite fiber may comprise a PP core and PE sheath in the body and poly(acrylic acid) in the coating.

In one particular embodiment, the composite fiber can consist of a body consisting of a PP core and a PE sheath, and a body consisting of a coating consisting of poly(acrylic acid).

It is preferred that the bicomponent fibers are entangled. The porous sheet can be a fibrous sheet, preferably woven or non-woven, more preferably non-woven.

Porous sheets, such as nonwovens, can have pores formed between the nonwoven fibers. In one embodiment, the porous sheet may comprise bicomponent fibers having a linear mass density in the range 0.1-100 dtex, preferably 0.3-10 dtex, more preferably 0.5-8 dtex.

One technical advantage of porous sheets is that they are lightweight.

The size and shape of the porous sheet will depend, for example, on the target of application. For example, the porous sheet may have a surface area ranging from 0.25 cm ² to 500 cm ² , preferably from 200 cm ² to 450 cm ² . Solid substrates typically have a density (basis weight) of 5 g/m ² to 400 g/m ² , preferably 5 g/m ² to 80 g/m ² . In one particular embodiment, the porous sheet has a density (grammage) of 5-40 g/m ² , preferably 10-30 g/m ² , more preferably 15-25 g/m ² . Grams per square meter or g/m ² is also known as gsm.

A porous sheet can be prepared by a thermal bonding method.

Porous sheets such as non-woven fabrics are
(i) extruding at least two polymeric materials;
(ii) forming a plurality of bicomponent fibers comprising said at least two polymers, preferably two non-polar polymers, more preferably two polyolefin polymers;
(iii) coating said composite fiber with at least one polymer, preferably one hydrophilic polymer, more preferably at least one hydrophilic acrylic polymer;
(iv) bonding the plurality of conjugate fibers by a bonding method.

In one embodiment, said bonding method (iv) comprises carding bonding and thermal bonding of said plurality of bicomponent fibers.

In one embodiment, said method comprises the steps of: (i) extruding at least two polymers in the same spinneret; and (ii) said at least two polymers, one polymer forming the core of the fiber body and the fiber body. forming a plurality of bicomponent fibers comprising another polymer forming a sheath of the fiber.

In one embodiment, the method includes carding said plurality of bicomponent fibers comprising said at least two polymers through warm air through a nonwoven web of fibers. This is referred to as the hot air method or heat bonding method.

In one preferred embodiment, the temperature for the hot air method of making the porous sheet is selected such that only the sheath of the fibrous body melts, leaving the core of the fibrous body in an unmelted form. Said thermal bonding is therefore advantageously carried out at a temperature for melting the sleece of the fiber body, but not the temperature for melting the core of the fiber body.

In one embodiment, said bonding method (iv) is carried out at a temperature in the range of 100°C to 230°C.

Advantageously, this warm air method results in a consoled material and provides the porous sheet with a fluffy, soft feel that is particularly needed for topical application, especially in cosmetic applications. Due to the non-melting of the fiber body, preferably its core, the prepared sheet remains in an open structure, which advantageously imparts a fluffy soft feel to the sheet.

The porous sheet used for the cosmetic method according to the invention contains water. The amount of water is not limited. However, it is preferred that the amount of water is 50% or more, preferably 70% or more, more preferably 90% or more of the water retention capacity of the porous sheet. Most preferably, the porous sheet is saturated with water.

In one embodiment, the porous sheet may be in the form of a face mask. In one preferred embodiment, the porous sheet may comprise at least one cosmetically active ingredient as described above.

In another embodiment, the porous sheet may be a wipe.

In one embodiment, the porous sheet may have a rounded shape, such as a circular or oval shape. In another embodiment, the porous sheet may have a polygonal shape.

In one embodiment, the porous sheet defines at least one central through-opening intended to receive the user's nose and at least two upper through-openings for placement in front of the user's eyes. may be in the form of a face mask capable of

Advantageously, the porous sheet has at least two through-openings intended to be placed facing the eyes of the user and another through-opening intended to be placed facing the mouth of the user. and may be provided. In one particular embodiment, the face mask may also include a slit delimiting a flapper intended to be displaced by the user's nose to delimit a nasal insertion through opening. In one variation, the slit delimits the through opening without a flapper. In one particular embodiment, the porous sheet is deformable when touched to conform to the conformation of the body or face surface.

[Kits, methods and uses]
The present invention also provides
a microneedle sheet comprising a base sheet and a plurality of microneedles on the base sheet, the base sheet comprising at least one water-soluble or water-dispersible polymer;
It also relates to a kit comprising a porous sheet comprising at least one composite fiber, preferably further comprising water, more preferably packaged together with water in a container.

The porous sheet in the kit according to the invention may be dry. In this case the porous sheet is wetted prior to use.

It is preferred that the porous sheet in the kit according to the invention contains water. In other words, it is preferred that the porous sheet in the kit according to the invention is wet.

More preferably, the porous sheet in the kit according to the invention is packaged in a container containing water.

The container may contain not only water, but also at least one cosmetically active ingredient as described above.

The container may preferably be a bag or sachet made from any material, preferably plastic or metal film. Aluminum foil, especially laminated aluminum foil, is more preferred as material for bags or sachets.

As such, the porous sheet may be folded prior to being placed in the container.

The kit can preferably be used for carrying out the cosmetic method according to the invention.

The present invention also provides a method for dissolving a base sheet of a base sheet and a microneedle sheet comprising a plurality of microneedles on the base sheet, wherein the base sheet comprises at least one water-soluble or comprising a water-dispersible polymer, the method comprising:
It also relates to a method comprising applying a porous sheet containing at least one bicomponent fiber and containing water over said base sheet.

The present invention is the use of a porous sheet comprising at least one composite fiber for dissolving a substrate sheet and a microneedle sheet comprising a plurality of microneedles on the substrate sheet, comprising: It relates to the use wherein said porous sheet comprises water and said base sheet comprises at least one water-soluble or water-dispersible polymer.

According to the above methods and uses according to the present invention, the base sheet of the microneedle sheet can be rapidly dissolved or disintegrated. In other words, the base sheet of the microneedle sheet can dissolve or disintegrate in a short period of time. Therefore, the base sheet of the microneedle sheet, which can impart an unpleasant touch, can be easily removed when the microneedle sheet is used and does not remain on the keratin material for a long period of time.

Therefore, the above methods or uses according to the present invention can reduce the time required for cosmetic treatment methods or non-therapeutic treatment methods using microneedle sheets.

The above descriptions of microneedle sheets and porous sheets for cosmetic methods according to the invention are also applicable to the descriptions of kits, methods and uses according to the invention.

The invention will be explained in more detail by means of examples. However, these examples should not be construed as limiting the scope of the invention. The following examples are presented as non-limiting illustrations of the field of the invention.

[Microneedle patch]
Microneedle sheets were prepared using sodium hyaluronate with an average molecular weight of 70,000 Daltons. The microneedle sheet had a plurality of microneedles at a density of 324 needles/cm ² on the base sheet. Each microneedle had the shape of a cone with a length or height of 200 μm and a base diameter of 200 μm. The pitch of the microneedles was 60 µm.

Microneedle sheets were prepared by standard mold casting methods. Sodium hyaluronate was dissolved in water and the aqueous solution of sodium hyaluronate thus obtained was injected into the cavity of the mold corresponding to the shape of the microneedles. After drying at room temperature to remove water, the microneedles in the cavity were demolded as a microneedle sheet with a plurality of microneedles on the base sheet.

A microneedle sheet was cut so that it had the shape of a patch to be applied under the eye.

[Textile patch]
The nonwoven fibrous sheet used in Example 1 was prepared using bicomponent fibers with a core composed of polypropylene (PP) and a sheath composed of polyethylene (PE). The bicomponent fibers were treated with an acrylic polymer and then converted into nonwoven fibrous sheets with a basis weight of 20 g/m ² using a thermal bonding method. The temperature of the thermal bonding process was 125° C., so that the sheath of the bicomponent fiber melted but the core of the bicomponent fiber remained unmelted, resulting in a fiber substrate.

A nonwoven fibrous sheet used in Comparative Example 1 was prepared using 50% cellulose fibers and 50% viscose rayon fibers. The basis weight of the nonwoven fiber sheet was 50 g/m ² .

A nonwoven fiber sheet used in Comparative Example 2 was prepared using PET fibers. The basis weight of the nonwoven fiber sheet was 50 g/m ² .

Table 1 shows the characteristics of the above three types of nonwoven fiber sheets.

Each of the three nonwoven fibrous sheets shown in Table 1 was cut so that it was in the shape of a patch to be applied under the eyes, and each nonwoven fibrous sheet patch was treated with 2 g of a liquid formulation containing the ingredients shown in Table 2. 24 hours in a sachet containing

Each of the nonwoven fibrous sheets was then removed from the sachet and the mass of liquid formulation remaining in the sachet was determined. In this manner, the amount of liquid formulation absorbed by each of the nonwoven fibrous sheets was determined. Table 3 shows the results.

Table 3 shows that the nonwoven fibrous sheet patch of Example 1 had greater liquid absorbency than the nonwoven fibrous sheet patches of Comparative Examples 1 and 2. Therefore, the nonwoven fibrous sheet patch of Example 1 was able to deliver a larger amount of liquid formulation than the nonwoven fibrous sheet patches of Comparative Examples 1 and 2. This was surprising in view of the fact that the basis weight of the fiber patch of Example 1 was less than that of the fiber patches of Comparative Examples 1 and 2, which indicates that the fiber patch of Example 1 It was implied that it appeared to have less absorbent material than the fibrous patches of Comparative Examples 1 and 2.

[evaluation]
(Example 1)
The microneedle patches thus prepared as described above were applied on artificial skin samples [Bio-Skin®] provided by Beaulax. For Example 1, the microneedle patch was then covered with a fiber patch.

After 15 minutes, the fiber patch was removed and microneedle patch residue was visually observed immediately and 45 minutes later (1 hour after application of the fiber patch).

(Comparative example 1)
The microneedle patches thus prepared as described above were applied on artificial skin samples [Bio-Skin®] provided by Beaulax. For Comparative Example 1, the microneedle patch was then covered with a fiber patch.

After 15 minutes, the fiber patch was removed and microneedle patch residue was visually observed immediately and 45 minutes later (1 hour after application of the fiber patch).

(Comparative example 2)
The microneedle patches thus prepared as described above were applied on artificial skin samples [Bio-Skin®] provided by Beaulax. For Comparative Example 2, the microneedle patch was then covered with a fiber patch.

After 15 minutes, the fiber patch was removed and microneedle patch residue was visually observed immediately and 45 minutes later (1 hour after application of the fiber patch).

(result)
The amount of microneedle patch residue on the artificial skin sample in Example 1 was less than that in Comparative Example 1 or Comparative Example 2 at both 15 minutes and 1 hour after application of the fiber patch. Ta.

This indicates that a nonwoven fibrous patch composed of bicomponent fibers could dissolve or disintegrate the base sheet of the microneedle patch in a faster or shorter period of time than does a conventional nonwoven fibrous patch. It meant that This can be attributed to the delivery of higher amounts of liquid formulations by nonwoven fibrous patches composed of bicomponent fibers.

Claims (15)

A microneedle sheet comprising a base sheet containing at least one water-soluble or water-dispersible polymer and a plurality of microneedles on the base sheet,
further comprising a nonwoven fabric comprising at least one composite fiber comprising a fiber body comprising at least two non-polar polymers and a coating comprising at least one hydrophilic polymer;
A microneedle sheet, wherein the nonwoven fabric contains water. The microneedle sheet of claim 1, wherein the microneedles have a height of 50-1000 microns. 3. The microneedle sheet according to claim 1 or 2, wherein the microneedles are cone-shaped. 4. The microneedle sheet of claim 3, wherein the base of the microneedle cones has a diameter of 50 to 350 microns. 5. The microneedle sheet according to claim 3, wherein the ratio of (height of cone)/(diameter of base of cone) of the microneedles is 1 or more. The water-soluble or water-dispersible polymer is hyaluronic acid , polysaccharide, dextrin, dextran, polyethylene glycol, polyvinyl alcohol, poly(methyl vinyl ether/maleic anhydride), polyvinyl pyrrolidone, poly(methyl/vinyl ether/maleic acid) (PMVE/ MA) and esters thereof, poly(methyl/vinyl ether/maleic anhydride) (PMVE/MAH), and mixtures thereof. The microneedle sheet according to any one of claims 1 to 6, wherein said water-soluble or water-dispersible polymer has a molecular weight of 10,000-200,000 Daltons. 8. The microneedle sheet according to any one of claims 1 to 7, wherein said composite fibers comprise a fiber body containing at least two polyolefin polymers. 9. The microneedle sheet according to claim 8, wherein said two polyolefin polymers are polypropylene and polyethylene . 10. The microneedle sheet according to any one of claims 1 to 9, wherein the hydrophilic polymer is a hydrophilic acrylic polymer . 11. The microneedle sheet according to any one of claims 1 to 10, wherein the nonwoven fabric is a nonwoven fabric prepared by a heat bonding method. 12. The microneedle sheet according to any one of claims 1 to 11, wherein at least one of said microneedles comprises at least one cosmetically active ingredient. a base sheet comprising at least one water-soluble or water-dispersible polymer; and a microneedle sheet comprising a plurality of microneedles on the base sheet;
and,
A kit comprising a fiber body comprising at least two non-polar polymers and a non-woven fabric comprising at least one bicomponent fiber with a coating comprising at least one hydrophilic polymer. A method for dissolving a base sheet of a microneedle sheet comprising a base sheet comprising at least one water-soluble or water-dispersible polymer and a plurality of microneedles on the base sheet, comprising:
said method comprising:
On the base sheet, a nonwoven fabric containing at least one composite fiber comprising a fiber body containing at least two non-polar polymers and a coating containing at least one hydrophilic polymer , and containing water. A method (other than a method for treatment) comprising the step of applying. a substrate sheet comprising at least one water-soluble or water-dispersible polymer; Use of a nonwoven fabric comprising a fiber body comprising a polymer and at least one bicomponent fiber with a coating comprising at least one hydrophilic polymer,
Uses (except for therapeutic uses) wherein said non-woven fabric contains water.