Film for care for keratin materials

Abstract

A mask for caring for keratin materials comprises A) a water-insoluble substrate layer, and B) a water-soluble layer disposed on the water-insoluble substrate layer wherein the water-soluble layer comprises (i) at least one hyaluronic acid (HA) or a salt thereof, and (ii) polydatin wherein the hyaluronic acid or a salt thereof has a weight average molecular weight of between 20,000 Daltons and 60,000 Daltons. A non-therapeutic method for caring for keratin materials includes using the mask.

Description

Technical Field

[0001] The present invention relates to a product for caring for keratin materials. In particular, the present invention relates to a mask for caring for keratin materials. The present invention also relates to a non-therapeutic method for caring for keratin materials. Background Art

[0002] The ultimate goal in the cosmetics field has always been to provide consumers with highly effective products that provide skin benefits such as hydration, moisturization, brightening, cleansing, etc.

[0003] Masks are popular with many consumers because they can leave the mask on their face for a period of time and then remove the mask without having to massage the face during application.

[0004] Nanofiber masks are a new type of sheet mask due to their instant water solubility and much less formulation waste, unlike conventional tissue masks made from nonwoven fibers.

[0005] Electrospinning is an existing technology for preparing nanofiber sheets from a spinning solution. Typically, the spinning solution consists of a polymer, a solvent, and optionally a functional active ingredient.

[0006] In this field, commonly used polymers are polyethylene oxide (PEO), polyvinyl alcohol (PVA), polyacrylonitrile (PAN), etc. Solvents can be water and organic solvents such as ethanol and N,N-dimethylformamide (DMF).

[0007] In the cosmetics field, some companies have developed spinning solutions containing sodium hyaluronate as a matrix. However, some of the proposed associations may not be environmentally friendly.

[0008] Additionally, some spinning solutions may produce a muddy effect on the skin after use, especially in the case of high doses of some actives.

[0009] Therefore, it is desirable that the risk of a muddy effect on the skin after use is low.

[0010] It is also desirable to have a uniform nanofiber film for nanofiber coating.

[0011] Therefore, it is sought to develop a mask for the care of keratin materials comprising a uniform, environmentally friendly nanofiber layer capable of dissolving quickly on contact with water, with a low risk of creating a muddy effect on the skin after use. SUMMARY OF THE INVENTION

[0013] One object of the present invention is to provide a mask having a uniform, environmentally friendly nanofibrous layer that dissolves quickly on contact with water and has a low risk of a rubbing effect on the skin after use.

[0014] Another object of the present invention is to provide a non-therapeutic method for caring for keratin materials.

[0015] In a first aspect, the present invention provides a mask for caring for keratin materials, comprising:

[0016] A) a water-insoluble substrate layer, and

[0017] B) a water-soluble layer disposed on the water-insoluble substrate layer, wherein the water-soluble layer comprises (i) at least one hyaluronic acid (HA) or a salt thereof, and (ii) polydatin,

[0018] The weight average molecular weight of the hyaluronic acid or its salt is between 10,000 Daltons and 80,000 Daltons.

[0019] Owing to the presence of hyaluronic acid (HA) or its salts and polydatin, the mask according to the invention can be used to care for keratin materials.

[0020] In a second aspect, the present invention provides a non-therapeutic method for caring for keratin materials comprising the steps of:

[0021] (i) applying a film according to the invention to a keratin material, wherein the water-soluble layer is in contact with the keratin material;

[0022] (ii) adding water to the film to dissolve the water-soluble layer;

[0023] (iii) removing the water-insoluble substrate from the keratin material; and

[0024] (iv) leaving the dissolved water-soluble layer on the keratin material.

[0025] Other characteristics and advantages of the invention will appear more clearly on reading the following description and examples. Detailed Description of the Invention

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention belongs. When the definition of a term in this specification conflicts with the meaning commonly understood by those skilled in the art to which this invention belongs, the definition described in this specification shall apply.

[0028] Hereinafter, and unless otherwise indicated, the upper and lower limits of a numerical range are included in the range, especially in the expressions "between and" and "ranging from to".

[0029] In addition, the expression "at least one" used in this specification is equivalent to the expression "one or more".

[0030] Throughout this application, the term "comprising" should be interpreted as encompassing all specifically mentioned features as well as optional, additional, unspecified features. As used herein, the use of the term "comprising" also discloses embodiments in which features other than those specifically mentioned are not present (i.e., "consisting of").

[0031] Unless otherwise indicated, all numerical values ​​expressing quantities of ingredients and the like used in the specification and claims are to be understood as modified by the term “about.” Accordingly, unless indicated to the contrary, the numerical values ​​and parameters described herein are approximations that can vary as necessary depending on the desired purpose.

[0032] As used herein, a uniform layer means that the layer has no lumps, nodules, or breaks when touched by hand.

[0033] As used herein, nanofiber means a fiber having a nanometer-sized diameter.

[0034] For the purposes of the present invention, the term "keratin material" is intended to encompass human skin. Facial skin is most particularly contemplated according to the present invention.

[0035] Unless otherwise specified, all percentages in the present invention are by weight.

[0036] Film

[0037] According to a first aspect, the present invention provides a mask for caring for keratin materials, comprising:

[0038] A) a water-insoluble substrate layer, and

[0039] B) a water-soluble layer disposed on the water-insoluble substrate layer, wherein the water-soluble layer comprises (i) at least one hyaluronic acid (HA) or a salt thereof, and (ii) polydatin,

[0040] The weight average molecular weight of the hyaluronic acid or its salt is between 10,000 Daltons and 80,000 Daltons.

[0041] Water-insoluble substrate layer

[0042] According to a first aspect, the coating according to the present invention comprises a water-insoluble substrate layer.

[0043] For the purposes of the present invention, the term "water-insoluble" means that the substrate layer is not soluble in water and that it does not disintegrate when immersed in water.

[0044] One skilled in the art can select an appropriate substrate layer and the weight ratio of substrate layer to water-soluble layer to be used based on the desired cosmetic benefit.

[0045] The substrate layer can be a woven fabric, a knitted fabric or a nonwoven fabric prepared from the following fibers: natural fibers, such as cotton fibers, pulp fibers, bamboo fibers and cellulose fibers; semi-natural fibers, such as viscose rayon fibers; and synthetic fibers, such as polyester fibers, polyethylene terephthalate fibers, polyethylene fibers and polypropylene fibers. Two or more selected from the above fibers can be used in combination.

[0046] The substrate layer may be composed of one or more sub-layers, wherein the materials of the sub-layers may be the same as or different from each other.

[0047] The substrate layer can have a variety of shapes, depending on the desired use and properties of the coating.

[0048] The substrate layer is typically designed to conform to the area of ​​skin to which the topical application is to be applied. For example, when the mask is applied to the face, the substrate layer is designed to conform to the shape of the face, avoiding the eye, nostril, and mouth areas as necessary.

[0049] Those skilled in the art can determine the thickness and texture of the substrate layer based on the intended purpose. In particular, the thickness and texture of the substrate layer are selected so that water can penetrate through the substrate and contact the water-soluble layer.

[0050] Water-soluble layer

[0051] According to a first aspect, the film coating according to the present invention comprises a water-soluble layer disposed on a water-insoluble substrate layer, wherein the water-soluble layer comprises (i) at least one hyaluronic acid (HA) or a salt thereof, and (ii) polydatin.

[0052] For the purposes of the present invention, the term "water-soluble layer" means that the layer is soluble in water upon contact with water.

[0053] Hyaluronic acid (HA) or its salt

[0054] Hyaluronic acid is a non-sulfated linear glycosaminoglycan composed of repeating units of D-glucuronic acid and N-acetyl-D-glucosamine.

[0055] The salt of hyaluronic acid may be selected from alkali metal salts, such as sodium and potassium salts; and other salts, such as zinc salts, silver salts; and mixtures thereof.

[0056] Preferably, the salt of hyaluronic acid is selected from alkali metal salts, other salts, or mixtures thereof; preferably selected from sodium salts, potassium salts, zinc salts, silver salts, and mixtures thereof; more preferably selected from sodium salts and potassium salts.

[0057] More preferably, the water-soluble layer comprises a salt of hyaluronic acid, more preferably sodium hyaluronate.

[0058] The inventors have found that a weight average molecular weight (MW) of hyaluronic acid or its salts between 10,000 Daltons and 80,000 Daltons is beneficial for forming uniform nanofibers.

[0059] Preferably, the weight average molecular weight (MW) of the hyaluronic acid or its salt is between 20,000 and 60,000 Daltons, preferably between 25,000 and 55,000 Daltons, more preferably between 30,000 and 50,000 Daltons.

[0060] For example, sodium hyaluronate is available from BLOOMAGE BIOTECHNOLOGY under the trade name HYBLOOM TM LOWMOLECULARWEIGHT SODIUM HYALURONATE(HA-TLM) for sale.

[0061] Advantageously, hyaluronic acid (HA) or a salt thereof is present in the water-soluble layer in an amount ranging from 25 to 85 wt.%, preferably from 40 to 80 wt.%, more preferably from 50 to 75 wt.%, relative to the total weight of the water-soluble layer.

[0062] Polydatin

[0063] According to the first aspect, the water-soluble layer of the present invention comprises polydatin.

[0064] Polydatin is a polyphenol belonging to the chemical family of stilbenes, also known as picea glycosides. Polydatin can be extracted from the roots and rhizomes of Polygonum cuspidatum and can also be found in a variety of other sources, such as grapes, peanuts, hop cones, red wine, hop pellets, cocoa-containing products, chocolate products, and many everyday dietary sources.

[0065] Polydatin includes trans-polydatin and cis-polydatin, and trans-polydatin isomerizes into cis-polydatin.

[0066] Preferably, the polydatin used in the water-soluble layer according to the present invention is selected from trans-polydatin, cis-polydatin, and a combination thereof.

[0067] Trans-polydatin is 3,4',5-trihydroxystilbene-3-β-mono-D-glucoside: a stilbene compound that is trans-resveratrol substituted with a β-D-glucosyl residue at the 3-position and has the following structure:

[0068]

[0069] As an example of a commercial product of polydatin, mention may be made of the one sold under the name Polygonum cuspidatum root extract by the company GUILIN LAYN NATURAL INGREDIENTS.

[0070] Advantageously, polydatin is present in the water-soluble layer in an amount ranging from 1 wt.% to 22 wt.%, preferably from 2 wt.% to 21 wt.%, more preferably from 3 wt.% to 15 wt.%, relative to the total weight of the water-soluble layer.

[0071] Advantageously, the weight ratio of hyaluronic acid or a salt thereof to polydatin present in the water-soluble layer is from 20:1 to 3:1, preferably from 15:1 to 4:1.

[0072] In some embodiments, the water-soluble layer consists of at least one hyaluronic acid or a salt thereof and polydatin as described above.

[0073] Other cosmetic active ingredients

[0074] In addition to hyaluronic acid (HA) or a salt thereof and polydatin, the water-soluble layer of the present invention may also contain one or more other cosmetic active ingredients.

[0075] A person skilled in the art can easily adjust the amount of additional cosmetic active ingredient based on the final use of the film according to the invention.

[0076] Additional adjuvants or additives

[0077] The water-soluble layer of the present invention may further comprise conventional cosmetic adjuvants or additives, such as fragrances, hydrotropes, preservatives, pH adjusters, and combinations thereof.

[0078] In some embodiments, the water-soluble layer comprises at least one conventional cosmetic adjuvant or additive, preferably at least one hydrotrope.

[0079] As examples of hydrotropes, mention may be made of nicotinamide and caffeine.

[0080] Preferably, the water-soluble layer comprises at least a hydrotrope selected from niacinamide, caffeine, and combinations thereof.

[0081] A person skilled in the art can choose the amount of additional adjuvants or additives so that the end use of the composition according to the invention is not adversely affected.

[0082] In some embodiments, the water-soluble layer comprises at least one hyaluronic acid or a salt thereof, polydatin, and at least one compound selected from the group consisting of a fragrance, a hydrotrope, a preservative, a pH adjuster, and combinations thereof.

[0083] Preferably, the water-soluble layer comprises sodium hyaluronate, polydatin, niacinamide and caffeine.

[0084] Preferably, the weight ratio of the water-insoluble substrate layer to the water-soluble layer ranges from 15:1 to 1:1.

[0085] More preferably, the weight ratio of the water-insoluble substrate layer to the water-soluble layer ranges from 8:1 to 2:1.

[0086] According to a particularly preferred embodiment, the present invention provides a mask for caring for keratin materials, comprising:

[0087] A) a water-insoluble substrate layer, and

[0088] B) a water-soluble layer disposed on the water-insoluble substrate layer, wherein the water-soluble layer comprises (i) sodium hyaluronate having a weight average molecular weight between 20,000 Daltons and 60,000 Daltons, and (ii) polydatin,

[0089] The weight ratio of sodium hyaluronate with a weight average molecular weight between 20,000 Daltons and 60,000 Daltons to polydatin present in the water-soluble layer is 15:1 to 4:1.

[0090] Preparation and use

[0091] The coating according to the present invention can be prepared by forming a water-soluble layer on a water-insoluble substrate layer through electrospinning.

[0092] The spinning solution for electrospinning comprises at least one hyaluronic acid (HA) or a salt thereof as described above, polydatin as described above, optionally other cosmetic active ingredients and optionally cosmetic adjuvants or additives in a solvent such as water.

[0093] The content of hyaluronic acid (HA) or its salt in the spinning solution can affect the structure of nanofibers and the quality of the membrane, thereby affecting the performance of the membrane.

[0094] When the content of hyaluronic acid (HA) or its salt is too low, the polymer chains break before reaching the collector, and the spinning solution may break into droplets without forming fibers, or filament breakage may also occur.

[0095] When the content of hyaluronic acid (HA) or its salt is too high, the spinning solution will not have good flowability, the electrostatic charge strength may be insufficient to stretch the solution to form nanofibers, and defective or beaded nanofibers may be obtained.

[0096] Preferably, the content of hyaluronic acid or its salt in the spinning solution is 2 wt.% to 30 wt.%, preferably 5 wt.% to 20 wt.%, more preferably 10 wt.% to 15 wt.%, relative to the total weight of the spinning solution.

[0097] Advantageously, polydatin is present in the spinning solution in an amount ranging from 0.01 wt.% to 10 wt.%, preferably from 0.1 wt.% to 5 wt.%, more preferably from 0.1 wt.% to 1 wt.%, relative to the total weight of the spinning solution.

[0098] Advantageously, the weight ratio of hyaluronic acid or a salt thereof to polydatin present in the spinning solution is from 20:1 to 3:1, preferably from 15:1 to 4:1.

[0099] Owing to the presence of hyaluronic acid (HA) or a salt thereof and polydatin, and optionally other cosmetic active ingredients, the mask according to the invention can be used to care for keratin materials.

[0100] The coating according to the present invention is a dry coating.

[0101] Here, the dry film means that no solvent is present in the film.

[0102] According to a second aspect, the present invention provides a non-therapeutic method for caring for keratin materials, comprising the steps of: (i) applying a film according to the invention to a keratin material, wherein the water-soluble layer is in contact with the keratin material;

[0103] (ii) adding water to the film to dissolve the water-soluble layer;

[0104] (iii) removing the water-insoluble substrate from the keratin material; and

[0105] (iv) allowing the dissolved water-soluble layer to remain on the keratin material.

[0106] Optionally, gentle massaging with fingers can be used for better absorption.

[0107] There is no need to rinse the keratin material after using the mask.

[0108] Preferably, after removing the water-insoluble substrate from a keratin material, such as skin, the keratin material is not rinsed.The keratin material may be skin, in particular facial skin and / or eye skin.

[0109] A mask as defined above is applied to at least one area of ​​the skin.

[0110] In particular, the mask as defined above is applied to the skin of the face and / or the skin of the eye. Example

[0111] The following examples serve to illustrate the invention but are non-limiting in nature.

[0112] The main raw materials used, their trade names and suppliers are listed in Table 1.

[0113] Table 1

[0114]

[0115] Inventive Examples 1-3 and Comparative Examples 1-4

[0116] Films of Inventive Examples (IE) 1-3 and Comparative Examples (CE) 1-5 were prepared.

[0117] First, spinning solutions of Inventive Examples (IE) 1-3 and Comparative Examples (CE) 1-4 were prepared based on the components given in Table 2. The amounts in Table 2 are given as weight % of active ingredient relative to the total weight of the spinning solution.

[0118] Table 2

[0119]

[0120] Then, a water-soluble layer was formed by electrospinning the spinning solutions of Inventive Examples (IE) 1-3 and Comparative Examples (CE) 1-4 according to Table 2 on a water-insoluble substrate layer composed of polyester fibers, wherein the weight ratio of the water-insoluble substrate layer to the water-soluble layer was 4:1.

[0121] The water-soluble layers obtained in Inventive Examples (IE) 1-3 and Comparative Examples (CE) 1-4 contained the components listed in Table 3. The amounts in Table 3 are given as weight % of active ingredient relative to the total weight of the water-soluble layer.

[0122] Table 3

[0123] Components IE.1 IE.2 IE.3 CE.1 CE.2 CE.3 CE.4 Sodium hyaluronate (MW = 20K ~ 60K) 64.14 57.35 57.64 63.40 67.28 0 0 Sodium hyaluronate (MW>100K) 0 0 0 0 0 64.14 0 Hydrolyzed sodium hyaluronate (MW=<5K) 0 0 0 0 0 0 64.14 Oxidized polyethylene 0 0 0 5.76 0 0 0 Polydatin 4.66 4.30 11.53 0 0 4.66 4.66 Niacinamide 21.87 26.88 21.61 21.61 22.94 21.87 21.87 caffeine 9.33 11.47 9.22 9.22 9.79 9.33 9.33

[0124] Evaluate

[0125] Nanofiber structure

[0126] The structures of the water-soluble layers obtained in Inventive Examples (IE) 1-3 and Comparative Examples (CE) 1-4 were observed using a scanning electron microscope.

[0127] It was found that a relatively uniform nanofiber network was formed in the water-soluble layers obtained in Inventive Examples (IE) 1-3 and Comparative Example (CE) 1. The nanofibers had an average diameter of approximately 150-250 nm. In contrast, a uniform nanofiber network was not formed in Comparative Examples (CE) 2-4.

[0128] Risk of mud rubbing

[0129] The risk of rubbing of each prepared mask was evaluated by a sensory expert on 6 volunteers using a specific hand gesture as follows:

[0130] 1) Apply the film to be evaluated on half of each volunteer's face;

[0131] 2) adding water to the film to dissolve the water-soluble layer;

[0132] 3) Remove the non-water-soluble layer and slide the knuckle across the volunteer's face using light pressure;

[0133] 4) Score the mud rubbing phenomenon on each volunteer's face according to the following criteria.

[0134]

[0135] The average scores of the mud-rubbing phenomenon are summarized in Table 4 .

[0136] Table 4

[0137] IE.1 IE.2 IE.3 CE.1 CE.2 CE.3 CE.4 Score by rubbing mud 0 0.2 0.5 4.5 N / A N / A N / A

[0138] N / A means that the risk of mudding was not assessed because a uniform nanofiber network was not formed on the water-insoluble layer.

[0139] It can be seen that the films obtained in Inventive Examples 1-3 contain a water-soluble layer of a uniform and environmentally friendly nanofiber structure, and the risk of a mud-rubbing effect on the skin after use is low.

Claims

1. A mask for caring for keratin materials, comprising: A) a water-insoluble substrate layer, and B) a water-soluble layer disposed on the water-insoluble substrate layer, wherein the water-soluble layer comprises (i) at least one hyaluronic acid (HA) or a salt thereof, and (ii) polydatin, The weight average molecular weight of the hyaluronic acid or its salt is between 10,000 Daltons and 80,000 Daltons.

2. The film according to claim 1, wherein the salt of hyaluronic acid is selected from alkali metal salts, other salts, or mixtures thereof; preferably selected from sodium salts, potassium salts, zinc salts, silver salts, and mixtures thereof; more preferably selected from sodium salts and potassium salts. The film according to claim 2 , wherein the water-soluble layer comprises sodium hyaluronate.

4. The film according to any one of claims 1 to 3, wherein the weight average molecular weight (MW) of the hyaluronic acid or its salt is between 20,000 Daltons and 60,000 Daltons, preferably between 25,000 Daltons and 55,000 Daltons, more preferably between 30,000 Daltons and 50,000 Daltons.

5. The film according to any one of claims 1 to 4, wherein the amount of hyaluronic acid (HA) or a salt thereof present in the water-soluble layer is in the range of 25 wt.% to 85 wt.%, preferably 40 wt.% to 80 wt.%, more preferably 50 wt.% to 75 wt.%, relative to the total weight of the water-soluble layer.

6. The film according to any one of claims 1 to 5, wherein the polydatin is selected from trans-polydatin, cis-polydatin, and a combination thereof.

7. The film according to any one of claims 1 to 6, wherein the amount of polydatin present in the water-soluble layer is in the range of 1 wt.% to 22 wt.%, preferably 2 wt.% to 21 wt.%, more preferably 3 wt.% to 15 wt.%, relative to the total weight of the water-soluble layer.

8. The film according to any one of claims 1 to 7, wherein the weight ratio of hyaluronic acid or a salt thereof to polydatin in the water-soluble layer is 20:1 to 3:1, preferably 15:1 to 4:

1.

9. The film according to any one of claims 1 to 8, wherein the water-soluble layer comprises at least one conventional cosmetic auxiliary or additive, preferably at least one hydrotrope.

10. The film coating according to any one of claims 1 to 9, wherein the water-soluble layer comprises at least one hydrotrope selected from niacinamide, caffeine, and combinations thereof.

11. The film coating according to any one of claims 1 to 10, wherein the weight ratio of the water-insoluble substrate layer to the water-soluble layer is in the range of 15:1 to 1:1, preferably 8:1 to 2:

1.

12. The film according to claim 1, comprising: A) a water-insoluble substrate layer, and B) a water-soluble layer disposed on the water-insoluble substrate layer, wherein the water-soluble layer comprises (i) sodium hyaluronate having a weight average molecular weight between 20,000 Daltons and 60,000 Daltons, and (ii) polydatin, The weight ratio of sodium hyaluronate with a weight average molecular weight between 20,000 Daltons and 60,000 Daltons to polydatin present in the water-soluble layer is 15:1 to 4:

1.

13. The coating according to any one of claims 1 to 12, wherein the substrate layer is a woven fabric, a knitted fabric or a non-woven fabric prepared from the following fibers: natural fibers, such as cotton fibers, pulp fibers, bamboo fibers and cellulose fibers; semi-natural fibers, such as viscose rayon fibers; and synthetic fibers, such as polyester fibers, polyethylene terephthalate fibers, polyethylene fibers and polypropylene fibers.

14. A non-therapeutic method for caring for keratin materials comprising the following steps: (i) applying the film according to any one of claims 1 to 13 to the keratin material, wherein the water-soluble layer is in contact with the keratin material; (ii) adding water to the coating to dissolve the water-soluble layer; (iii) removing the water-insoluble substrate from the keratin material; as well as (iv) leaving the dissolved water-soluble layer on the keratin material.

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