Abstract
There is provided a multi-layered sheet mask comprising at least (a) a porous first layer having a first side and a second side, wherein the first side is opposite to the second side, and comprises a plurality of three-dimensional patterns extending therefrom; (b) a second layer attached to the second side of the porous first layer, the second layer comprising at least one pouch for receiving or containing at least one first active ingredient; a porous support structure; an air pouch that is sandwiched between the second side of the porous first layer and the porous support structure; and a plurality of microchannels that extend from the pouch and beyond the first side of the porous first layer when the air pouch is deflated; and (c) a third layer attached to the second layer for receiving or containing at least one second active ingredient. There is also provided a mould for producing the three-dimensional patterns of the porous first layer of the multi-layered sheet mask, and a method of producing the multi-layered sheet mask.
Claims
1. A multi-layered sheet mask comprising at least a) a porous first layer having a first side and a second side, wherein the first side is opposite to the second side, and comprises a plurality of three-dimensional patterns extending therefrom; b) a second layer attached to the second side of the porous first layer, the second layer comprising at least one pouch for receiving or containing at least one first active ingredient; a porous support structure; an air pouch that is sandwiched between the second side of the porous first layer and the porous support structure; and a plurality of microchannels that extend from the pouch and beyond the first side of the porous first layer when the air pouch is deflated; and c) a third layer attached to the second layer for receiving or containing at least one second active ingredient.
2. The multi-layered sheet mask according to claim 1, wherein the porous first layer and the porous support structure of the second layer comprise a plurality of slits.
3. The multi-layered sheet mask according to claim 1, wherein the porous first layer and the three-dimensional patterns are made of a material independently selected from the group consisting of synthetic, regenerated and natural biocompatible materials.
4. The multi-layered sheet mask according to claim 3, wherein the material is selected from the group consisting of UV-curable polymer, UV-LED curable polymer, bioabsorbable polymer, cotton, nylon, nylon microfibre, regenerated cellulose fibre, biocellulose, foil, hyaluronic acid, and hydrogel.
5. The multi-layered sheet mask according to claim 1, wherein the three-dimensional patterns comprise an exfoliating agent selected from the group consisting of alpha hydroxy acids, beta hydroxy acids, plant-based enzymes, animal-based enzymes and mixtures thereof; or wherein the three-dimensional patterns comprise an exfoliating agent selected from the group consisting of lactic acid, lactobionic acid, glycolic acid, hydroxycaproic acid, hydroxycaprylic acid, citric acid, malic acid, mandelic acid, tartaric acid, phytic acid, salicylic acid, hyaluronic acid, azelaic acid, kojic acid, ascorbic acid, trichloroacetic acid, alguronic acid, lipoic acid, ferulic acid and mixtures thereof; or wherein the three-dimensional patterns have an average diameter in a range of 1 μm to 1 mm, and a height in the range of 1 mm to 3 mm.
6. (canceled)
7. The multi-layered sheet mask according to claim 1, wherein the three-dimensional patterns comprise a plurality of pointed three-dimensional shapes as skin-engaging ends, wherein the pointed three-dimensional shapes are selected from the group consisting of cone, pyramid, stellated polyhedron, regular polyhedron, irregular polyhedron partial regular polyhedron, partial irregular polyhedron, sphere and at least one cone, sphere and at least one spike, sphere and at least one pyramid, hemisphere and at least one spike, spike, and combinations thereof.
8. The multi-layered sheet mask according to claim 5, wherein the pointed three-dimensional shapes have a height in a range of 200 μm to 250 μm.
9. The multi-layered sheet mask according to claim 7, wherein when the pointed three-dimensional shapes comprise of at least one spike, each spike has a length in a range of 40 μm to 100 μm.
10. The multi-layered sheet mask according to claim 9, wherein the spike is further positioned at an angle in a range of 10° to 30° from a vertical plane.
11. The multi-layered sheet mask according to claim 1, wherein the slits of the porous first layer and slits of the porous support structure of the second layer have an inner diameter in a range of 1 μm to 100 μm, and an outer diameter in a range of 100 μm to 150 μm.
12. The multi-layered sheet mask according to claim 1, wherein the slits of the porous first layer and slits of the porous support structure of the second layer have a shape selected from the group consisting of polyhedron, non-polyhedron, and combinations thereof; or wherein the slits of the porous first layer and slits of the porous support structure of the second layer have a shape selected from the group consisting of cylinder, prism, and combinations thereof; or wherein the slits of the porous first layer and slits of the porous support structure of the second layer have a hexagonal prism shape.
13. The multi-layered sheet mask according to claim 1, wherein the microchannels of the second layer have a height corresponding to different zones of a face as follows: a height in the range of 1.5 mm to 1.8 mm corresponding to a first zone consisting of hairline, forehead, temple and combinations thereof of the face; a height in the range of 1.2 mm to 1.5 mm corresponding to a second zone consisting of nose, cutaneous upper lip, philtum, philtum crest, cutaneous lower lip, chin, and combinations thereof of the face; and a height in the range of 1.6 mm to 1.9 mm corresponding to a third zone consisting of cheeks, midface, jawline, and combinations thereof of the face, or wherein the microchannels comprise pointed tips which penetrate the second side of the porous first layer, the first side of the porous first layer, an epidermis layer of a skin, and a dermis layer of a skin, when the air pouch is deflated.
14. (canceled)
15. The multi-layered sheet mask according to claim 1, wherein the at least one first active ingredient in each of the at least one pouch of the second layer is the same or different from each other; and wherein the first active ingredient is selected from the group consisting of anti-pigmentation agent, anti-ageing agent, anti-wrinkle agent, anti-acne agent, moisturizing agent, treatment agent, and mixtures thereof.
16. The multi-layered sheet mask according to claim 1, wherein the third layer is portioned into a number of parts, each part receiving or containing the at least one second active ingredient that is the same or different from each other; and wherein the second active ingredient is selected from the group consisting of oil, chemical sunscreen, anti-pigmentation agent, anti-ageing agent, anti-wrinkle agent, anti-acne agent, moisturizing agent, treatment agent, and mixtures thereof, or wherein a circumferential edge comprising the circumferential edges of the porous first layer, the second layer, and the third layer, having a width of at least 5 mm.
17. (canceled)
18. A mould for producing the three-dimensional patterns of the porous first layer of the multi-layered sheet mask according to claim 1, wherein the mould comprises a negative replica of the three-dimensional patterns.
19. The mould according to claim 18, further comprising a plurality of holes in sub-micrometre scale within the negative replica.
20. The mould according to claim 18, wherein the mould is transparent; or wherein the mould is formed by polymerizing a resin over a printed mould comprising a positive replica of the three-dimensional patterns.
21. A method of producing a multi-layered sheet mask, the method comprising the steps of: a) forming a porous first layer having a first side and a second side, by contacting a mask-shaped biocompatible material with a whole facial mask mould having a plurality of three-dimensional patterns thereon, wherein the three-dimensional patterns comprise a material selected from the group comprising of biocompatible material, exfoliating agent and combinations thereof, and drying for a duration; b) attaching a second layer to the second side of the porous first layer by bonding the circumferential edges of the first and second layers together; and c) attaching a third layer to the second layer by bonding the circumferential edges of the second and third layers together; wherein the multi-layered sheet mask comprises at least a porous first layer wherein the first side is opposite to the second side and comprises a plurality of three-dimensional patterns extending therefrom; a second layer attached to the second side of the porous first layer, the second layer comprising at least one pouch for receiving or containing at least one first active ingredient; a porous support structure; an air pouch that is sandwiched between the second side of the porous first layer and the porous support structure; and a plurality of microchannels that extend from the pouch and beyond the first side of the porous first layer when the air pouch is deflated; and a third layer attached to the second layer for receiving or containing at least one second active ingredient.
22. The method according to claim 21, wherein the three-dimensional patterns of step (a) are formed by filling sections of the whole facial mask mould with the material of step (a) and vacuuming for a duration; and wherein the sections comprise a mould for producing the three-dimensional patterns of the porous first layer of the multi-layered sheet mask, wherein the mould comprises a negative replica of the three-dimensional patterns, or wherein the sections of the whole facial mask mould correspond to facial areas selected from the group consisting of hairline, forehead, temple, nose, cutaneous upper lip, philtum, philtum crest, cutaneous lower lip, chin, cheeks, midface, jawline, and combinations thereof.
23. (canceled)
24. The method according to claim 21, wherein the attaching step (b) further comprises the step of applying fastening strips between the first and second layers; or wherein the attaching step (c) further comprises the step of applying fastening strips between the second and third layers; or wherein the bonding of steps (b) and (c) bonds at least a width of 5 mm of the circumferential edges.
25. (canceled)
Description
DESCRIPTION OF DRAWINGS
[0147] The accompanying drawings illustrate a disclosed embodiment and serve to explain the principles of the disclosed embodiment. It is to be understood, however, that the drawings are designed for purposes of illustration only, and not as a definition of the limits of the invention.
[0148] FIG. 1 is a schematic cross-sectional illustration of the multi-layered sheet mask 5000 applied on the skin 1 comprising dermis layer 2, epidermis layer 3 and stratum corneum 4, where the multi-layered sheet mask 5000 comprises the following components: porous first layer 5, three-dimensional patterns 6, second layer 7, air pouch 8, porous support structure 9, pouch 10 for receiving or containing at least one first active ingredient, microchannel 11, third layer 12, second active ingredient 13, and slits 14. The direction of flow of active ingredients as indicated by arrow 20 which is pointing from the mask 5000 towards the skin 1.
[0149] FIG. 2A is a schematic illustration of different zones A, B and C of a facial skin based on different skin thickness, where the microchannels of the second layer of the multi-layered sheet mask have different heights in corresponding to the skin thickness of each of these zones.
[0150] FIG. 2B is a schematic illustration of the foldable edges (dotted lines) of the multi-layered sheet mask.
[0151] FIG. 3A is a schematic illustration of an example of a design for the porous first layer of the multi-layered sheet mask that has various patterns of three-dimensional patterns at different regions corresponding to the facial skin.
[0152] FIG. 3B is schematic illustration of an example of a design for the porous first layer of the multi-layered sheet mask of FIG. 3A with a close-up view of the various patterns of three-dimensional patterns corresponding to different regions of the facial skin.
[0153] FIG. 4 is a schematic illustration of an example of a design for the second layer of the multi-layered sheet mask that has pouches positioned at different regions corresponding to different parts of the facial skin, each pouch 21 containing at least one first active ingredient and designed to be activated by one or more twist- and turn-valves 22. The darker regions in this figure (such as below the eyes area or above the lip area) correspond to the microchannel positions that extend across the first layer to illustrate the flow of the active ingredient(s) (such as serum) through the first layer and into the facial skin at the specific locations. For clarity, the darker regions are not represented by reference numerals 21 and 22 but are the darker regions (represented by the darker dots) in the other parts of the multi-layered sheet mask.
[0154] FIG. 5A is a drawing featuring an example of a 3D-printed mould of three-dimensional pattern with pointed three-dimensional shape comprising multiple spikes on two tiers, some spikes positioned at an angle from the vertical plane.
[0155] FIG. 5B is a drawing featuring an array design of the 3D-printed mould of three-dimensional pattern of FIG. 5A.
[0156] FIG. 5C is a microscopic side view of the 3D-printed mould of three-dimensional pattern of FIG. 5A.
[0157] FIG. 5D is a microscopic isometric view of the 3D-printed mould of three-dimensional pattern of FIG. 5A.
[0158] FIG. 5E is a microscopic top view of the 3D-printed mould of three-dimensional pattern of FIG. 5A.
[0159] FIG. 6A is a drawing featuring an example of a 3D-printed mould three-dimensional pattern with pointed three-dimensional shape comprising a cluster of multiple spikes on the centre of a hemisphere, some spikes positioned at an angle from the vertical plane.
[0160] FIG. 6B is a drawing featuring an array design of the 3D-printed mould of three-dimensional pattern of FIG. 6A.
[0161] FIG. 6C is a microscopic side view of the 3D-printed mould of three-dimensional pattern of FIG. 6A.
[0162] FIG. 6D is a microscopic isometric view of the 3D-printed mould of three-dimensional pattern of FIG. 6A.
[0163] FIG. 6E is a microscopic top view of the 3D-printed mould of three-dimensional pattern of FIG. 6A.
[0164] FIG. 7A is a drawing featuring an example of a 3D-printed mould of three-dimensional pattern with pointed three-dimensional shape comprising a spike on the centre of a hemisphere.
[0165] FIG. 7B is a drawing featuring an array design of the 3D-printed mould of three-dimensional pattern of FIG. 7A.
[0166] FIG. 7C is a microscopic side view of the 3D-printed mould of three-dimensional pattern of FIG. 7A.
[0167] FIG. 7D is a microscopic isometric view of the 3D-printed mould of three-dimensional pattern of FIG. 7A.
[0168] FIG. 7E is a microscopic top view of the 3D-printed mould of three-dimensional pattern of FIG. 7A.
[0169] FIG. 8 is a drawing featuring an array design of the 3D-printed mould of three-dimensional pattern with pointed three-dimensional shape comprising a partial irregular polyhedron.
[0170] FIG. 9 is a microscopic view of the three-dimensional patterns filled with hyaluronic acid as an exfoliating agent, wherein the three-dimensional patterns are based on pointed three-dimensional shape of (a) according to FIG. 5A, (b) according to FIG. 6A, (c) according to FIG. 7A, and (d) according to FIG. 8.
[0171] FIG. 10 is a schematic illustration of the first side 30 of the porous first layer 5 of the multi-layered sheet mask with three-dimensional patterns 6 that have different pointed three-dimensional shapes as skin-engaging ends, such as the stellated polyhedron 41, sphere and cones 42, and partial irregular polyhedron 43.
[0172] FIG. 11A is a schematic illustration of the first side 30 of the porous first layer 5 of the multi-layered sheet mask with three-dimensional patterns 6 having a diameter 51 and a height 52.
[0173] FIG. 11B is a schematic illustration showing some examples of three-dimensional patterns 6 with a diameter 51, a height 52, and a height of the corresponding pointed three-dimensional shape 53 of the three-dimensional pattern 6. The three-dimensional pattern may have various spike designs 60.
[0174] FIG. 12 is a schematic diagram illustrating the process of preparing a polymeric mould comprising a negative replica of the three-dimensional patterns (steps 1 and 2) and thereafter preparing a three-dimensional pattern which is a positive replica of the 3D-printed mould (steps 3 and 4).
[0175] FIG. 13 is a schematic diagram illustrating the general process of preparing the porous first layer of a multi-layered sheet mask.
[0176] FIG. 14 is a schematic diagram illustrating the process of preparing a whole facial mask which forms the complete porous first layer of a multi-layered sheet mask where the three-dimensional patterns in the porous first layer comprise an exfoliating agent.
[0177] FIG. 15 is a schematic diagram illustrating a whole facial mask mould design depicting (a) dimension of the whole facial mask, and (b) whole facial mask design with hollow areas as positions for mould comprising negative replica of three-dimensional patterns, wherein the whole facial mask forms the complete porous first layer of a multi-layered sheet mask.
[0178] FIG. 16 is a photo of a prototype 3D-printed whole facial mask with (200) hollow areas as positions for mould comprising negative replica of three-dimensional patterns, wherein the whole facial mask forms the complete porous first layer of a multi-layered sheet mask. This mould can be used as a sheet mask mould as mentioned above.
[0179] FIG. 17A is a photo of a prototype of a whole cellulose facial mask with three-dimensional patterns comprising hyaluronic acid, wherein the whole cellulose facial mask forms the complete porous first layer of a multi-layered sheet mask.
[0180] FIG. 17B is a photo of a prototype whole cellulose facial mask with three-dimensional patterns comprising hyaluronic acid at specific positions labelled as 300, 400, 500, 600, 700, 800 and 900, while the ring boundary 1000 prevents the leakage of active ingredients from the mask. The whole cellulose facial mask forms the complete porous first layer of a multi-layered sheet mask as defined herein. When used as a first layer of the multi-layered sheet mask, the three-dimensional patterns that comprises hyaluronic acid puncture the skin and thus improve permeation into the skin.
[0181] FIG. 18 shows the results of a skin test where (A) is a graph depicting the skin permeation of lidocaine over time and (B) is a chart depicting lidocaine in skin deposit after minutes, for skin treated with patches of four different designs of three-dimensional patterns. Here, the first layer was used for testing whereby all of the three-dimensional patterns were made of hyaluronic acid.
DETAILED DESCRIPTION OF DRAWINGS
[0182] FIG. 1 is a schematic cross-sectional illustration of the multi-layered sheet mask 5000 applied on the skin 1 comprising dermis layer 2, epidermis layer 3 and stratum corneum 4. The porous first layer 5 of the multi-layered sheet mask 5000 has a plurality of three-dimensional patterns 6 thereon. These three-dimensional patterns 6 with pointed three-dimensional shapes penetrate through the stratum corneum 4 during exfoliation. Some of the three-dimensional patterns 6 pass through the stratum corneum 4 and some of three-dimensional pattern 6 reach the dermis layer 2. The three-dimensional patterns 6 may be inserted from within the porous first layer 5 of the multi-layered sheet mask 5000 or may be formed on the surface of the first side of the porous first layer 5 of the multi-layered sheet mask 5000. Slits 14 are arranged within the support structure 9 of the second layer 7, as well as within the porous first layer 5 to allow the first active ingredient to flow from the pouch 10 in the second layer 7 to the surface of the skin 4 when the first active ingredient is released to flow from the pouch 10 by activating a twist-and-turn valve on the pouch 10 or when the pouch 10 is punctured by the microchannels 11. The slits 14 may have a hexagonal prism shape. The second layer 7 of the multi-layered sheet mask 5000 incorporates at least a pouch 10 for receiving or containing a first active ingredient and an air pouch 8. Each of the microchannels 11 has two ends, where one end is inserted into the pouch 10 and the other end comprising a pointed three-dimensional shape which penetrates the dermis layer 2 of the skin when the air pouch 8 is deflated. The three-dimensional patterns 6 may have a hollow center for the pointed microchannel 11 to penetrate through. The third layer 12 of the multi-layered sheet mask 5000 incorporates a second active ingredient 13 for cosmetic enhancement as needed. For instance, the third layer 12 may be portioned into a number of parts that contain chemical sunscreen or oil. Alternatively, the third layer 12 may have the second active ingredient 13 encapsulated in a pouch to be released by activating a twist-and-turn valve in the pouch. The second active ingredient 13 will pass through the second layer 7 and the porous first layer 5 to the skin 1 through the slits 14. The direction of flow of active ingredients is indicated by arrow 20. Optionally, a detachable fourth layer (not shown in FIG. 1) may be incorporated above the third layer 12 to provide further cosmetic functions such as final cleansing of the facial surface.
[0183] FIG. 2A is a schematic illustration of different zones A, B and C of a facial skin based on different skin thickness, where the microchannels of the second layer of the multi-layered sheet mask have different heights corresponding to each of these zones. When the microchannels are used in combination with the three-dimensional patterns of the multi-layered sheet mask, for instance when the air pouch in the second layer is deflated, some of the microchannels penetrate the three-dimensional patterns into the skin or directly into the skin to deliver a portion of the first active ingredient (e.g., collagen or moisturizer), while another portion of first active ingredient flows through the slits in the second and first layers to reach the skin. The type and volume of first active ingredient to be supplied to each of the zone may be arranged by tailoring the contents of the pouch or pouches in the second layer of the multi-layered sheet mask. Hence, exfoliation and stimulation of collagen formation or hydration can be performed on a facial skin of varying skin thickness in different zones to achieve a more targeted treatment. As an example, the depth of penetration in each zone is as follows: zone A—1500 to 1800 μm; zone B—1200 to 1500 μm; and zone C—1600 to 1900 μm. Additionally, when the mould of FIG. 16 is used as a sheet mask mould, polymeric moulds that are used to form the three-dimensional patterns can be inserted into each of the voids in regions A, B and C in FIG. 2A and a solution material for the three-dimensional patterns filled into the polymeric moulds. Thereafter, a mask-shaped biocompatible material, such as cellulose, can be pressed onto the polymeric moulds using the sheet mask mould of FIG. 16.
[0184] FIG. 4 is a schematic illustration of an example of a design for the second layer of the multi-layered sheet mask that has pouches positioned at different regions corresponding to different parts of the facial skin, each pouch 21 containing at least one first active ingredient and designed to be activated by one or more twist-and-turn valves 22. For example, the pouch 21 at the forehead region has a diameter of about 70 mm by about 60 mm, and each of the three corresponding twist-and-turn valves 22 for at least one first active ingredient elution have a diameter of about 10 mm. Each of the pouch 21 at the cheeks have a diameter of about 50 mm by about 40 mm, and the corresponding twist-and-turn valve 22 for at least one first active ingredient elution have a diameter of about 10 mm. The volume of pouch in each zone is about 1 ml to 50 ml.
[0185] FIG. 11A is a schematic illustration of the first side 30 of the porous first layer 5 of the multi-layered sheet mask with three-dimensional patterns 6 that have pointed three-dimensional shape in the shape of cones, having a diameter 51 and a height 52. The three-dimensional patterns 6 may have different heights in order to penetrate different depths of facial skin.
[0186] FIG. 11B is a schematic illustration showing some examples three-dimensional patterns 6, with a diameter 51, a height 52 and a height of the corresponding pointed three-dimensional shape 53 of the three-dimensional pattern 6, The three-dimensional patterns 6 can have various spike designs 60 which can be positioned vertically on a three-dimensional pattern or positioned at an angle from the vertical plane on a three-dimensional pattern. The three-dimensional patterns 6 and the pointed three-dimensional shape 53 may have different heights in order to penetrate different depths of facial skin. Further, the angle and direction of the spike(s) 60 may also vary for different skin thickness and skin condition to achieve different treatment effects. As mentioned above, where the spike is positioned at an angle from the vertical plane, the spike may have higher penetration area from the angle and from an adjacent area of a center spike, as compared to a spike that is not positioned at an angle from the vertical plane. Additionally, when the spike is positioned at an angle from the vertical plane, the spike may have a different depth of penetration when the first layer of the multi-layered sheet mask is compressed, as compared to a spike that is not positioned at an angle.
[0187] FIG. 12 is a schematic diagram illustrating the process of preparing a polymeric mould comprising a negative replica of the desired three-dimensional pattern for the porous first layer of the multi-layered sheet mask (i.e., steps 1 and 2) and thereafter preparing a three-dimensional pattern which is a positive replica of the 3D-printed mould (i.e., steps 3 and 4). For instance, step 1 involves casting and curing a polymeric material, such as polydimethylsiloxane (PDMS), on a 3D-printed mould, and step 2 involves removing the cured polymeric mould from the 3D-printed mould. The polymeric mould thus obtained comprises a negative replica of the desired three-dimensional pattern. Thereafter, in step 3, a solution material for the three-dimensional pattern is filled into the polymeric mould obtained from step 2. Thereafter, in step 4, the three-dimensional pattern is subjected to curing, removal of a portion of the polymeric mould to expose the three-dimensional pattern formed within, and post-curing the three-dimensional pattern at an elevated temperature for a duration. The three-dimensional pattern thus obtained may be incorporated into the porous first layer of the multi-layered sheet mask such that the three-dimensional patterns function as a mechanical exfoliator (rather than comprising the exfoliating agent therein).
[0188] FIG. 13 is a schematic diagram illustrating the general process of preparing the porous first layer of a multi-layered sheet mask. Firstly, step 100 involves preparing a 3D-printed solid master mould with positive replica of desired three-dimensional patterns. The solid master mould may be made of steel. Thereafter, step 110 involves casting a polymeric material such as polydimethylsiloxane (PDMS) over the 3D-printed solid master mould. Step 120 involves curing the PDMS polymer on the master mould and ejecting the cured polymer to obtain a polymeric mould 130 with negative replica of the three-dimensional patterns. Next, step 140 involves casting a biocompatible material which is a polymer solution or melt, for example gelatin methacrylate (GelMA), over the polymeric mould, applying vacuum in step 150. The polymeric mould may comprise a plurality of holes in sub-micrometre scale within the negative replica, such that when vacuum is applied in step 150, air suction causes the biocompatible material in a solution or melt form to fill the entire contours of the polymeric mould 130 to effectively assume the positive replica shape of the three-dimensional patterns. Thereafter, UV radiation is applied in step 160 to cure the biocompatible material, followed by peeling off in step 170 to obtain the formed three-dimensional patterns 180. The polymeric mould 130 may also be transparent and the environment in step 160 may be filled with inert gas such as nitrogen or argon, with continuous vacuum applied such that UV radiation in step 160 can penetrate all sides of the polymeric mould to induce curing of the biocompatible material. The step of 160 will not be inhibited by oxygen for radical polymerization if the solution formulation for the biocompatible material is UV curable. The biocompatible material may be woven or non-woven and alternatively, the biocompatible material may be hot pressed on the polymeric mould to form the three-dimensional patterns 180 instead of undergoing steps 140, 150 and 160.
[0189] FIG. 14 is a schematic diagram illustrating the process of preparing a whole facial mask which forms the complete porous first layer of a multi-layered sheet mask. A solution of hyaluronic acid is filled in the sections of the whole facial mask mould comprising three-dimensional patterns to form three-dimensional patterns comprising hyaluronic acid as exfoliating agent. Thereafter, the whole facial mask mould is brought into contact with a mask-shaped biocompatible material, such as cellulose, and secured using stainless steel rods and needle heads to form an assembly to ensure adequate contact between the mask-shaped biocompatible material and the hyaluronic acid. The formed whole facial mask is removed from the whole facial mask mould after the hyaluronic acid solution has completely dried.
[0190] FIG. 18 shows the results of a skin test where (A) is a graph depicting the skin permeation of lidocaine over time and (B) is a chart depicting lidocaine in skin deposit after 60 minutes, for skin treated with patches of four different designs of three-dimensional patterns as compared to control which is a cream applied to the skin directly without any treatment. Design 1 to 4 correspond to the three-dimensional patterns shown in FIG. 5A, FIG. 6A, FIG. 7A and FIG. 8 respectively. Design 1 showed the highest lidocaine absorption and had the highest lidocaine skin deposits among the four designs.
EXAMPLES
[0191] Non-limiting examples of the invention will be further described in greater details by reference to specific Examples, which should not be construed as in any way limiting the scope of the invention.
Example 1: Synthesis of 3D-Printed Moulds
[0192] Models of the 3D-printed moulds comprising positive replicas of the desired three-dimensional patterns were designed using SolidWorks (Dassult Systèmes, USA) to have various pointed three-dimensional shapes and synthesized by 3D printing using a Titan 2HR 3D printer (Kudo 3D, USA) with Optoma Projector with light spectrum >=400 nm (visible range) as the light source, light intensity set at 3000 lumens, slicing software from Creation workshop, resin (3DM cast from ADMAT of France), layer splicing at 25 μm, pixel resolution at 26 μm and exposure time set at 6 to 16 seconds.
Example 2: Synthesis of Polymeric Mould and Three-Dimensional Patterns
[0193] With reference to FIG. 12, FIG. 12 provides the steps used to make the mould and to generate the three-dimensional patterns.
Materials
[0194] Polydimethylsiloxane (PDMS) is a two-part polymer (Base Elastomer and Curing Agent). Here, Sylgard 184 from Dow Corning was used. The standard mixing ratio for PDMS is 10-parts base elastomer and 1-part curing agent. This ratio provides the mechanical properties that are desirable and optimum biocompatibility. The solution material (or precursor solution) for three-dimensional pattern can be any biocompatible material but in this example, hyaluronic acid was used as the solution material (or precursor solution).
Procedure
[0195] Firstly, to prepare the polymeric solution, the base elastomer and curing agent of the PDMS were mixed at a ratio recommended by the manufacturer which is a base to curing agent ratio of 10:1 (by parts) and de-aired for 30 minutes by applying negative pressure of −95 kPa. The polymeric solution was poured onto the cured 3D-printed mould in a container and vacuumed at −95 kPa for 30 minutes to ensure that bubbles were removed completely. The container containing the polymeric solution was cured at 80° C. for 30 minutes. After the polymeric solution was completely cured, the 3D-printed mould was removed from the cured polymeric mould by applying a force to detach the 3D-printed mould from the cured polymeric mould (which is a polydimethylsiloxane mold). This is a pre-casting step to create two halves of the negative replica of the 3D-printed mold.
[0196] Thereafter, hyaluronic acid (4 g of HA in 20 ml DI water for 20% stock HA solution) was filled into the microneedles of the polymeric PDMS mould and the whole 3D printed PLA mask mold was put under vacuum at 95 kPa for 30 minutes. The cellulose mask sheet was placed on top of the PLA mould with PDMS negative needles filled with hyaluronic in the PDMS mould and ensuring the cellulose sheet is in contact with the hyaluronic acid three-dimensional patterns. A weight was placed and secured with stainless steel rods to ensure good contact between the mask and the filled casted HA solution in the PDMS mould. The cellulose mask with filled HA solution was left dried at room conditions for at least 48 hours. After the HA solution was completely dried out, the cellulose mask with the HA three0dimensional patterns was removed from the mould, thus forming the first layer of the multi-layered sheet mask.
Example 3: Synthesis of Prototype Polymeric Mould, Prototype Whole Facial Mask Mould and Porous First Layer of Multi-Layered Sheet Mask
Materials
[0197] The following materials were purchased commercially for use in this example without modification: hyaluronic acid molecular weight 8 to 15 kDa (MakingCosmetics, USA), Sylgard 184 silicon elastomer kit (Dow Corning, USA), polylactic acid (PLA, Makerbot Industries, USA), 3DM-CAST resin (ADMAT, France) and mask-shaped cellulose (under brand name BIO-Celtox™ obtained from Guangzhou Yurui Cosmetics Co., Ltd, China) and isopropyl alcohol. De-ionised water was used.
Procedure
Digital Light Processing (DLP) Printing Method
[0198] Titan 2HR 3D printer (Kudo 3D, USA) was used to print the 3D-printed mould of the three-dimensional patterns. The three-dimensional patterns may be specific to a certain zone on the facial skin, as shown in FIG. 15B. The Titan 2HR 3D printer uses optoma projector with light spectrum ≥400 nm wavelength (visible range) as its light source. A model of the 3D-printed mould was designed using SolidWorks (Dassult Systèmes, USA) and sliced using Creation Workshop (XAYAV, USA). The 3D printer was calibrated prior to printing. Sliced STL files of the model of the 3D-printed mould were uploaded to the 3D printer and printing parameters settings are as shown in Table 1.
TABLE-US-00001 TABLE 1 Printing Parameters of DLP Printing Method Parameter Value Light intensity 3000 lumens Layer Slicing 25 μm Pixel resolution 26 μm Exposure time 6 to 16 seconds
[0199] The 3D-printed mould was washed two times at 15 minutes per wash using isopropyl alcohol. Thereafter, the 3D-printed mould was air-dried at room temperature followed by post-curing under UV irradiation for 30 minutes. Multiple 3D-printed moulds may be synthesized for different zones of facial skin. Examples of the 3D-printed moulds of three-dimensional patterns are shown in FIG. 5A to FIG. 8.
Casting of Polymeric Solution
[0200] A schematic diagram illustrating this process is shown in FIG. 12. Firstly, to prepare the polymeric solution, silicone elastomer was mixed at a ratio recommended by the manufacturer at base to curing agent ratio of 10:1 (by weight) and de-aired for 30 minutes by applying negative pressure of −95 kPa. The polymeric solution was poured onto the cured 3D-printed mould in a container and vacuumed at −95 kPa for 30 minutes. The container was placed in an oven at 80° C. for 2 hours for curing. After the polymeric solution was completely cured, the 3D-printed mould was removed from the cured polymeric mould. The cured prototype polymeric mould was ready for precursor solution filling. As the prototype polymeric mould may be specific to a certain zone on facial skin, multiple prototype polymeric moulds may be synthesized before assembly with a whole facial mask mould.
Fused Deposition Modeling (FDM) Printing Method
[0201] MakerBot Replicator Z18 (Makerbot Industries, USA) and biodegradable polylactic acid (PLA, Makerbot Industries, USA) were used to make the prototype whole facial mask mould. A model of the whole facial mask mould was designed using SolidWorks (Dassult Systèmes, USA) according to the printing parameters settings shown in Table 2. The whole facial mask mould was designed with hollow portions on the forehead, under eyelids, cheeks, nose, smile lines, upper lip lines and chin as shown in FIG. 16, as these facial areas are to be filled with the prototype polymeric mould prepared as disclosed above, such that these facial areas would have their corresponding three-dimensional patterns in the whole facial mask mould. The polymeric mould was slotted inside designated holes on the whole facial mask mould. Alternatively, the whole facial mask mould as shown in FIG. 16 may be used as a sheet mask mould to contact a first layer material onto three-dimensional patterns when into onto their respective three-dimensional moulds.
TABLE-US-00002 TABLE 2 Printing Parameters of FDM Printing Method Parameter Value Layer height 200 μm Infill 10% Material Biodegradable polylactic acid Extruder parameter 215° C. Print bed temperature 90° C.
Preparation of Whole Facial Mask Comprising an Exfoliating Agent
[0202] A schematic diagram illustrating the process to prepare a whole facial mask which forms the porous first layer of a multi-layered sheet mask, where the three-dimensional patterns comprise an exfoliating agent is shown in FIG. 14. Firstly, 4 g of hyaluronic acid was dissolved in 20 mL deionised water to prepare a stock hyaluronic acid solution. The slits of the porous first layer and slits of the porous support structure of the second layer can be formed by integrating honey comb protrusion on negative PDMS mold. The HA solution will be casted on the honey comb protruded structure PDMS mold. The hyaluronic acid solution was filled only in the areas of the whole facial mask mould that had the negative replica of the three-dimensional patterns (i.e., areas covered by the prototype polymeric moulds), and the whole facial mask mould was vacuumed at −95 kPa for 30 minutes. Thereafter, the whole facial mask mould was brought into contact with a mask-shaped cellulose and secured using stainless steel rods and needle heads to form an assembly to ensure adequate contact between the mask-shaped cellulose and the casted hyaluronic acid solution. The assembly was left to dry at room temperature for 2 days. After the casted hyaluronic acid solution was completely dried, the mask-shaped cellulose comprising hyaluronic acid three-dimensional patterns was removed from the whole facial mask mould. A photo of the whole cellulose facial mask comprising hyaluronic acid three-dimensional patterns is as shown in FIG. 17A, and a breakdown of the various parts of the whole cellulose facial mask is as shown in FIG. 17B.
Example 4: Skin Test
Materials
[0203] The following materials were purchased commercially for use in this example without modification: lidocaine, diclofenac sodium, acetonitrile HPLC grade (Merck, USA), ethanol, ammonium formate (Merck, USA), phosphate buffered saline (PBS, Vivantis, Singapore). Water used was purified by Mili-Q system. Human cadaver dermatone skin used for the analysis was obtained from Science Care (Phoenix, AZ, USA). The experiment was conducted using vertical Franz diffusion cells at 32° C. with an effective exposed area of 1 cm.sup.2. The skin piece used in this experiment had a thickness of 150 μm to 200 μm and area of 2×2 cm.
Procedure
[0204] An active ingredient composition used in this experiment comprised 23% lidocaine and 1% diclofenac sodium in the form of a cream. 5 mL of phosphate buffered saline (PBS) in the receptor compartment was used as the medium for absorption of the active ingredient composition. The test was conducted by applying patches containing three-dimensional patterns according to designs of FIG. 5A, FIG. 6A, FIG. 7A and FIG. 8 on the skin as treatment, before applying the active ingredient composition on the treated skin. For control, the skin was not treated with any patch. Thereafter, 1 mL samples were collected from the receptor medium after a time of 10 minutes, 20 minutes, 40 minutes, and 60 minutes and the same amount was replaced with fresh PBS. After 60 minutes of sample collection from the receptor medium, the rest of the receptor medium was discarded, the cream on the skin was removed and the skin was washed with PBS to remove residual cream. Washed skin was dispersed in 70% ethanol for 24 hours to extract the absorbed lidocaine content. All samples were analysed using a validated high pressure liquid chromatography (HPLC) method as shown in Table 3.
TABLE-US-00003 TABLE 3 Validated HPLC Method Instrument Shimadzu LC-20AD with SDP-M20A UV detector (from Shimadzu Corporation, Japan) Column C18 UV detection 225 nm Mobile phase Organic phase (acetonitrile), aqueous phase (50 mM ammonium composition formate) Program Gradient flow At 0 minute 80% 50 mM ammonium formate, 20% acetonitrile To 9 minute 30% 50 mM ammonium formate, 70% acetonitrile; At 9.01 minute 80% 50 mM ammonium, 20% acetonitrile; To 12 minute 80% 50 mM ammonium formate, 20% acetonitrile Flow rate 0.8 mL/minute Injection volume 20 μL
[0205] Based on the results in FIG. 18A, treatment of the skin with patches containing three-dimensional patterns increased the skin absorption of lidocaine at all time points compared to the control which did not receive treatment. However, the extent of absorption of lidocaine varied according to different designs of three-dimensional patterns. Design 1 showing the highest lidocaine absorption corresponds to the three-dimensional pattern with pointed three-dimensional shape comprising multiple spikes on two tiers, some spikes positioned at an angle from the vertical plane as in FIG. 5A. Further, based on the results of FIG. 18B, Design 1 also had the highest lidocaine skins deposits compared to other designs. However, the lidocaine deposits were highest for the control. The high amount of lidocaine deposits in the skin while having low lidocaine absorption for the untreated skin suggests that the lidocaine in the untreated skin only remains in the stratum corneum layer of the skin. In contrast, lidocaine deposits in the treated skin were much lower but had higher lidocaine absorption. Further, an un-quantifiable amount of lidocaine may be metabolized in the skin, thus converting the lidocaine to metabolites that were not detected. The lidocaine skin deposits that were quantified corresponds to unmetabolized lidocaine in the skin.
INDUSTRIAL APPLICABILITY
[0206] The multi-layered sheet mask as disclosed herein may be used as a skincare product or a skin treatment product for providing a variety of cosmetic enhancements for facial skin, such as pigmentation alleviation, anti-wrinkle, anti-ageing, anti-acne, collagen growth stimulation and hydration. The multi-layered sheet mask may also be applied to other skin areas on the body besides facial skin.
[0207] The mould as disclosed herein may be used in the cosmetics, personal care and biomedical industries to produce complex three-dimensional patterns for enhanced skin engagement. The method as disclosed herein may be used in the cosmetics, personal care and biomedical industries to produce multi-layered structures that combine different functionalities of each layer into a single structure, with enhanced delivery of active ingredients into skin.
[0208] It will be apparent that various other modifications and adaptations of the invention will be apparent to the person skilled in the art after reading the foregoing disclosure without departing from the spirit and scope of the invention and it is intended that all such modifications and adaptations come within the scope of the appended claims.
