WO2022110183A1

WO2022110183A1 - Mask composition and process

Info

Publication number: WO2022110183A1
Application number: PCT/CN2020/132880
Authority: WO
Inventors: Lixuan KE
Original assignee: L'oreal
Priority date: 2020-11-30
Filing date: 2020-11-30
Publication date: 2022-06-02
Also published as: FR3116725A1; CN116568179A; FR3116725B1

Abstract

It relates to a mask for caring for keratin materials, comprising: (1) at least one hydrogel layer (s); (2) at least one fibre-based layer (s), wherein at least one fibre-based layer is the layer that is closer to keratin materials than all hydrogel layer (s) present in the mask. It also relates to a process for preparing the same and its uses.

Description

MASK COMPOSITION AND PROCESS

FIELD OF THE INVENTION

The present invention relates to a mask composition for topical application which comprises a water-insoluble substrate including composition providing functional benefit to the skin. Further, the present invention relates to the corresponding non-therapeutic process involving use of same mask.

BACKGROUD OF THE INVENTION

A sheet which is formed by a substrate sheet such as a non-woven fabric sheet impregnated with a lotion or the like has be used for cosmetic treatments of the skin, in particular the face. Such masks for cosmetic treatment are disclosed, for example in the patent application WO 02/062132, which provides acute skin tone changing benefit to the skin.

It is also known to use actives in the cosmetic products for treating or caring for the skin, such as hydration, whitening, anti-aging, pore minimizing, freshness, smoothness, softness, and so on. Among which, skin conditioning effect, such as hydration, is always an interest to consumers around the world. Cosmetic masks that are impregnated with lotion containing skin conditioning agents are suitable for applying on the skin to provide especially skin hydration effect. Answering to this demand, various masks have been developed.

Besides the activity agents, the support of the mask is an important part. At present, the general products of masks on market is divided into two types: one uses a non-woven type fabrics sheet, the other uses a gel type sheet.

The disadvantage of a mask made by a fiber-like sheet can only hold or load limited amount of a functional liquid including activity agent (s) , wherein the activity agent (s) included in the fiber-like sheet is directly exposed in air. Therefore, the application time of the mask made of fiber-like sheet is limited in a short period because the activity agent (s) included in the fiber-like sheet is volatilized or become dry in short period. Such mask made by a fiber-like sheet cannot provide no continuous effects on skin. Moreover, the mask made by a fiber-like sheet has sufficient moisture at beginning of use, which causes the skin to absorb too much water; then, as the mask made by a fiber-like sheet dries, the mask made by a fiber-like sheet absorbs water from the skin in reverse, which will make the skin uncomfortable, for example, drawing tight.

The disadvantage of a mask made by a gel sheet is that, as the gel sheet is normally used as a support material, it must be used together with the fluid formulae; otherwise no cosmetic efficacy can be delivered to the skin. In other words, the mask made by a gel sheet doesn't have good delivery of actives to the skin even with the filling of a functional liquid including activity agent (s) .

However, the up-to-date masks are still to be improved especially in terms of long-term active effects with high amount activity agents.

Based on the foregoing, there is a need for a mask which is efficient in delivering the skin conditioning actives to the skin with high amounts of actives during application for a long-term. In particular, there exists a need for a mask with high loading of actives (for example, providing good skin conditioning benefit, in particular moisturizing, freshness, smoothness, and softness etc. to the skin) , and at the same time, an excellent delivery capability when applying on the skin.

DISCLOSURE OF THE INVENTION

An objective of the present invention is to provide a novel solid hydrogel sheet mask with high loading amount of actives, and with an excellent delivery capability. The present mask is efficient in delivering the skin conditioning actives to the skin with high amounts of actives during application for a long-term.

The above objective of the present invention can be achieved by a mask comprising at least:

(1) a fibre-based layer (s) as defined in the present invention;

(2) a hydrogel layer (s) as defined in the present invention, which contact with the fibre-based layer, optionally comprising active agent (s) ;

wherein at least one fibre-based layer is the layer that is closer to keratin materials after application than any hydrogel layer (s) present in the mask.

Another aspect of the present invention is to provide a process for preparing the mask, comprising the steps of:

- providing a fibre-based layer;

- providing a hydrogel layer comprising active agent (s) ,

- coating the fibre-based layer on the hydrogel layer.

Another aspect of the present invention is to provide a skin wound dressing, comprising at least:

(1) a fibre-based layer (s) as defined in the present invention;

wherein at least one fibre-based layer is the layer that is closer to keratin materials than all hydrogel layer (s) present.

These and other features, aspects, and advantages of the present invention will become better understood from a reading of the following description, and the claims.

Preferably, the “keratin material” according to the present invention is the skin. By “skin” , we intend all the body skin, including the scalp. Still preferably, the keratin material is the face, or neck, especially the face.

By “topical application” , it meant that the composition is applied or spread onto the surface of the keratin material, such as the skin.

DETAILED DESCRIPTION OF THE INVENTION

In that which follows and unless otherwise indicated, the limits of a range of values are included within this range, in particular in the expressions "between…and" and"from... to... " .

The terms “a, ” “an, ” and “the” are understood to encompass the plural as well as the singular.

The expression “at least one” means “one or more” and vice versa, and thus includes individual components as well as mixtures/combinations.

The term “about” when referring to a value, is meant specifically that a measurement can be rounded to the value using a standard convention for rounding numbers. For example, “about 1.5” is 1.45 to 1.54. All values set forth herein can be modified with the term “about, ” if desired to impart the meaning above, or recited without the term, regardless of whether the term “about” is specifically set forth (or is absent) in conjunction with any particular value in the specification.

According to the present invention, the mask comprises a mask for caring for keratin materials, comprising at least:

(1) a fibre-based layer (s) as defined in the present invention;

wherein at least one fibre-based layer is the layer that is closer to keratin materials than all hydrogel layer (s) present in the mask.

Hydrogel layer

The hydrogel layer used in the present mask is an insoluble solid hydrogel layer, in which, actives are optionally added. Generally, all kinds of insoluble solid hydrogel layer comprising at least one water soluble alkali metal salt that are acceptable in the cosmetic field can be used in the present invention.

The hydrogel layer is prepared by the following substances comprising water, a gel-forming composition, and at least one water soluble alkali metal salt.

Gel-forming composition

According to one aspect, the gel-forming composition according to the present invention comprises at least one hydrophilic thickener (also known as an aqueous-phase-thickening polymer) .

There is no particular limitation to the hydrophilic thickener. For example, the hydrophilic thickener may be selected from the following compounds:

(i) homopolymers or copolymers of acrylic or methacrylic acid or salts thereof and esters thereof

Examples that may be mentioned in particular include the products sold under the names Versicol F or Versicol K by the company Allied Colloid, Ultrahold 8 by the company Ciba-Geigy, Cosmedia SP by the company BASF, Lecigel (mixture of sodium acrylates copolymer/lecithin) by the company Lucas Meyer Cosmetics; polyacrylic acids of Synthalen K type, and salts, especially sodium salts, of polyacrylic acid (corresponding to the INCI name sodium acrylate copolymer) and more particularly a crosslinked sodium polyacrylate (corresponding to the INCI name sodium acrylate copolymer (and) caprylic/capric triglyceride) sold under the name Luvigel EM.

Mention may also be made of polyacrylic acid/alkyl acrylate copolymers, preferably modified or unmodified carboxyvinyl polymers, most particularly acrylate/C10-C30-alkyl acrylate copolymers (INCI name: Acrylate/C 10-30 Alkyl Acrylate Crosspolymer) such as the products sold by the company Lubrizol under the trade names Pemulen TR1, Pemulen TR2, Carbopol 1382, Carbopol EDT 2020 and even more preferentially Pemulen TR-2; copolymers of methacrylic acid, of methyl methacrylate, of methylstyrene isocyanate and of PEG-40 behenate (INCI name: polyacrylate-3) (Viscophobe DB 1000 sold by the company Dow) ,

(ii) copolymers of acrylic acid and of acrylamide

Mention may be made of those in the form of the sodium salt thereof sold under the Reten names by the company Hercules, the sodium polymethacrylate sold under the name Darvan No. 7 by the company Vanderbilt, and the sodium salts of polyhydroxycarboxylic acids sold under the name Hydagen F by the company Henkel.

(iii) homopolymers and copolymers based on acrylamidopropanesulfonic acid

Mention may be made of for instance:

- polyacrylamidomethylpropanesulfonic acid partially neutralized with aqueous ammonia and highly crosslinked, for example the product Hostacerin AMPS sold in particular by the company Clariant,

- copolymers of acrylamidopropanesulfonic acid/acrylamide for example of Sepigel or Simulgel type sold especially by the company SEPPIC,

- polyoxyethylenated acrylamidopropanesulfonic acid/alkyl methacrylate copolymers (crosslinked or non-crosslinked) of the type such as,inter alia, Aristoflex HMS and Aristoflex TAC, sold by the company Clariant,

- copolymers of acrylamidomethylpropanesulfonic acid and of hydroxyethyl acrylate, for instance the acrylamidomethylpropanesulfonic acid/hydroxyethyl acrylate copolymer especially such as the product used in the commercial product sold under the name Simulgel NS by the company SEPPIC, or the acrylamido methylpropanesulfonic acid/hydroxyethyl acrylate copolymer especially such as the product used in the commercial product sold under the name Sepinov EMT 10 sold by the company SEPPIC (INCI name: Hydroxyethyl acrylate/sodium acryloyldimethyl taurate copolymer) ;

- copolymers of acrylamidomethylpropanesulfonic acid and of vinylpyrrolidone, such as the product Aristoflex AVC (ammonium acryloyldimethyl taurate/VP copolymer in water) sold by the company Clariant; and

- mixtures thereof.

Alternatively, the hydrophilic thickener may be selected from:

- anionic, cationic, amphoteric or nonionic chitin or chitosan polymers;

- cellulose polymers, in particular (C ₁-C ₃) hydroxyalkylcelluloses, selected from hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, hydroxymethylcellulose, ethylhydroxyethylcellulose, carboxymethylcellulose and quatemized derivatives of cellulose;

- vinyl polymers, for instance polyvinylpyrrolidones, copolymers of methyl vinyl ether and of malic anhydride, the copolymer of vinyl acetate and of crotonic acid, copolymers of vinylpyrrolidone and of vinyl acetate; copolymers of vinylpyrrolidone and of caprolactam; polyvinyl alcohol,

- optionally modified polymers of natural origin, such as galactomannans and derivatives thereof, for instance carrageen gum, konjac gum, gellan gum, locust bean gum, fenugreek gum, karaya gum, gum tragacanth, gum arabic, acacia gum, guar gum and derivatives thereof (carboxymethyl guar, hydroxypropyl guar, hydroxypropyl guar modified with sodium methylcarboxylate groups (Jaguar XC97-1, Rhodia)) , xanthan gum and derivatives thereof;

- alginates and carrageenans, for example, carrageenans of the μ, κ, v, ι or λθ type, and mixtures thereof in all proportions, preferably κ type;

- mucopolysaccharides such as hyaluronic acid;

- and mixtures thereof.

According to some embodiments, the thickening polymer is selected from xanthan gum, carrageenan gum, konjac gum, guar gum, hydroxypropyl gum, locust beam gum and carboxymethylcellulose.

According to some embodiments, the composition according to the present invention comprises carrageenan gum and konjac gum as hydrophilic gums.

According to some embodiments, the composition according to the present invention comprises xanthan gum and konjac gum as hydrophilic gums.

According to some embodiments, the composition according to the present invention comprises hyroxypropyl guar as hydrophilic gum.

In order to increase the gel strength, the composition according to the present invention may further comprise a cross-linking agent.

As examples of cross-linking agent, mention can be made of sodium borate.

According to one embodiment, the composition according to the present invention comprises hydroxypropyl guar as hydrophilic gum and borax as cross-linking agent.

Under the teaching of the present description, the skilled in the art can adjust the amount and/or type of the thickening agent and/or the cross-linking agent to obtain the composition according to the present invention.

In some preferred embodiments, the composition according to the present invention comprises carrageenan gum and konjac gum as hydrophilic gums, the total amount of carrageenan gum and konjac gum is from 0.2wt. %to 10 wt. %, relative to the total weight of the composition.

In some preferred embodiments, the composition according to the present invention comprises xanthan gum and konjac gum as hydrophilic gums, the total amount of xanthan gum and konjac gum is from 0.5 wt. %to 10 wt. %, relative to the total weight of the composition.

In some preferred embodiments, the composition according to the present invention comprises hydroxypropyl guar as hydrophilic gum, the amount of hydroxypropyl guar is from 0.5wt. %to 10 wt. %, relative to the total weight of the composition.

In some preferred embodiments, the composition according to the present invention comprises hydroxypropyl guar as hydrophilic gum and borax as cross-linking agent, the amount of hydropropyl guar is from 0.5 wt.%to 10 wt. %, relative to the total weight of the composition.

As commercial product of carrageenans, mention can be made of those sold under the names Satiagum UTC 30 Carrageenan lamda Cargill, Satiagum UTC 10 Carrageenan lamda, and Cargill SATIAGEL ^TM UHD 300 by the company Cargill, under the name CARRAGEENAN BLK120 by the company BLG and under the name of KA120LMO by the company Greenfresh.

As commercial product of konjac gum, mention can be made of that sold under the name KONJAC GEL CKAA1220 by the company XieLi, and that sold under the name KONJAC FLOUR HWG1002 by the company BLG.

As commercial product of xanthan gum, mention can be made of that sold under the name KELTROL CG or KELTROL CG-T by the company CP KELCO; and under the name RHODICARE XC by the company PMC OUVRIE.

As commercial product of hydroxypropyl guar, mention can be made of that sold under the name JAGUAR HP 105 SGI by RHODIA (SOLVAY) .

Water soluble alkali metal salt

In one embodiment of the present invention, the water soluble alkali metal salt that can be used in the present invention comprises all kinds of alkali metals (e.g. Li, Na, K, etc. ) that form soluble salts (chlorides, nitrates, etc. ) acceptable in the cosmetic field.

In one embodiment of the present invention, the water soluble alkali metal salt is selected from water soluble alkali metal salt of inorganic acid (s) and/or organic acid (s) . The water soluble alkali metal salt of inorganic acid is selected from, for example, selected from alkali metal chlorides, alkali metal salt nitrates, alkali metal citrate, alkali metal sulfate, alkali metal carbonate, alkali metal bicarbonate, alkali metal phosphate, alkali metal acetate, and the like. The water soluble alkali metal salt of organic acid is selected from, for example, alkali metal salt of EDTA, alkali metal salt of carboxylic acid, alkali metal salt of lactic acid, alkali metal salt of acetic acid, alkali metal salt of formic acid, alkali metal salt of uric acid, alkali metal salt of malic acid, alkali metal salt of tartaric acid, and the like.

In one embodiment of the present invention, the alkali metal is selected from Li, Na, and K.

In one embodiment of the present invention, the water soluble alkali metal salt is selected from ethylenediaminetetraacetic acid disodium salt (i.e. EDTA disodium salt) , and sodium citrate.

In one embodiment of the present invention, the amount of the water soluble alkali metal salt is between 0.01 and 15wt. %by weight, preferably between 0.05 and 12wt. %by weight, or between 0.1 and 10wt. %by weight, or even between 1 and 8wt. %by weight, relate to the weight of hydrogel layer.

In one embodiment of the present invention, the weight of the hydrogel layer ranges from 400g/m ² to 1600g/m ².

In addition to water, the water soluble alkali metal salt and the hydrophilic thickener mentioned above, the hydrogel layer of the present invention may further comprises additional components.

Additional components

As additional components, mention can be made of water-miscible or at least partially water-miscible compounds for improving hydration feeling, for instance C ₂ to C ₈ lower polyols or monoalcohols, such as ethanol and isopropanol.

The term “polyol” should be understood as meaning any organic molecule comprising at least two free hydroxyl groups. Examples of polyols include glycols, for instance pentylene glycol, butylene glycol, propylene glycol, and isoprene glycol, caprylyl glycol, glycerol (i.e. glycerin) and polyethylene glycols.

As additional components, mention can be also made of sebum-absorbing ingredient.

The sebum-absorbing ingredient may be inorganic or organic sebum-absorbing particles. The particles of one or more inorganic compounds used in the hydrogel layer may have different shapes, for example spheres, full or hollow, glitter, needles or platelets and preferably they are approximately spherical.

More precisely, the sebum-absorbing particles may be selected from:

- silica powders,

- polyamide

powders,

- powders of acrylic polymers, especially of polymethyl methacrylate, poly (methyl methacrylate/ethylene glycol dimethacrylate) , poly (allyl methacrylate/ethylene glycol dimethacrylate) , ethylene glycol dimethacrylate/lauryl methacrylate copolymer,

- powders of silicone elastomer, obtained especially by polymerization of organopolysiloxane containing at least two hydrogen atoms each bonded to a silicon atom and of an organopolysiloxane comprising at least two ethylenically unsaturated groups (especially two vinyl groups) in the presence of a platinum catalyst,

- polylactic acid,

- cellulose,

- talc,

- carbon black,

- perlite

- clays, and

- a mixture thereof.

The sebum-absorbing particle may be a powder coated with a hydrophobic treatment agent.

The hydrophobic treatment agent may be selected from fatty acids, for instance stearic acid; metal soaps, for instance aluminium dimyristate, the aluminium salt of hydrogenated tallow glutamate; amino acids; N-acylamino acids or salts thereof; lecithin, isopropyl triisostearyl titanate, waxes, and mixtures thereof.

The N-acylamino acids may comprise an acyl group containing from 8 to 22 carbon atoms, for instance a 2-ethylhexanoyl, caproyl, lauroyl, myristoyl, palmitoyl, stearoyl or cocoyl group. The salts of these compounds may be the aluminium, magnesium, calcium, zirconium, zinc, sodium or potassium salts. The amino acid may be, for example, lysine, glutamic acid or alanine.

As non-limiting illustrations of sebum-absorbing particles according to the invention, mention may be made most particularly of the particles below.

Silicas that can be used may be natural and untreated. Mention may thus be made of the silicas provided under the names Sillitin N85, Sillitin N87, Sillitin N82, Sillitin V85 and Sillitin V88 by Hoffmann Mineral.

They may be fumed silicas.

The fumed silicas can be obtained by high-temperature hydrolysis of a volatile silicon compound in an oxyhydrogen flame, producing finely divided silica. This process makes it possible especially to obtain hydrophilic silicas which contain a large number of silanol groups at their surface. It is possible to chemically modify the surface of the said silica via a chemical reaction which brings about a reduction in the number of silanol groups. It is possible especially to substitute silanol groups with hydrophobic groups; a hydrophobic silica is then obtained.

The hydrophobic groups can be:

(a) trimethylsiloxyl groups, which are obtained especially by treating fumed silica in the presence of hexamethyldisilazane. Silicas thus treated are known as "Silica silylate" according to the CTFA (6th Edition, 1995) ;

(b) dimethylsilyloxyl or polydimethylsiloxane groups, which are obtained especially by treating fumed silica in the presence of polydimethylsiloxane or dimethyldichlorosilane. Silicas thus treated are known as “Silica dimethyl silylate” according to the CTFA (6th Edition, 1995) .

Silica powders that may more particularly be mentioned include:

- the porous silica microspheres sold under the name Silica Beads SB-700 by Miyoshi;

H51,

H33 by Asahi Glass;

- the polydimethylsiloxane-coated amorphous silica microspheres sold under the name SA

H33 and SA

H53 by Asahi Glass;

- the precipitated silica microspheres, for example coated with inorganic wax such as polyethylene, and sold especially under the name Acematt OK 412 by Evonik Degussa

- Silica silylate, such as DC VM-2270 sold by the company DOW CORNING and KTL 10 sold by the company TOKUYAMA.

Acrylic polymer powder that may be mentioned included:

Acrylate copolymer powder, such as EXPANCEL 551 sold by the company AKZO NOBEL;

Laurylmethacrylate/glycol dimethacrylate crosspolymer powder, such as Polytrap 6603 sold by the company AMCOL HEALTH&BEAUTY SOLUTIONS;

Polymethyl methacrylate, such as SEPIMAT H10 sold by the company MATSUMOTO YUSHI-SEIYAKU.

A Nylon powder that may be mentioned is the Nylon powder sold under the name

4000 by Atochem.

The silicone elastomers are especially elastomeric partially or completely crosslinked organopolysiloxanes, having a three-dimensional structure, such as those sold under the names

and

by SHIN-ETSU, Trefil

and Trefil

by DOW-CORNING, Gransil

SR

SR 5CYC

SR DMF 10

and SR DC 556

by GRANT INDUSTRIES, SF

and JK

by GENERAL ELECTRIC.

Silicone elastomer powders that may be mentioned include the powders sold under the names "

Powder E-505C" and "

Powder E-506C" by Dow Corning.

As silicone powder, gum beads of crosslinked polydimethylsiloxane coated with silsesquioxane resin may be mentioned, especially sold under the name KSP100 by Shin Etsu, silicone resin powders in the form of rugby balls such as especially the product sold under the name NLK-602 by TAKEMOTO.

As polylactic acid, mention can be made to TORAYPEARL PLA sold by the company TORAY INDUSTRIES.

As cellulose powder, mention can be made to CELLULOBEADS USF sold by the company DAITO KASEI.

Perlite is a natural glass of volcanic origin, shiny light-grey or black in colour, which results from the rapid cooling of lava and which is provided in the shape of small particles resembling pearls.

The perlite particles used according to the invention are especially commercially available from World Minerals Europe under the trade name Perlite P1430, Perlite P2550 or Perlite P2040. These particles are sold as mattifying agents for paints. They are presented in the form of a white powder having a crystalline silica content below 0.1wt. %, related to the total weight of the composition.

Preferably, the perlite particles according to the invention have a particle size distribution such that at least 50wt. %of the particles have a size of less than 25μm, preferably of less than 20μm. In addition, they preferably have a particle size distribution such that 90 wt. %by weight of the particles have a size of less than 55μm and preferably of less than 40 μm. Furthermore, it is preferable for 90wt. %by weight of the particles to have a size of greater than 5μm.

Boron nitride particles may be mentioned, such as PUHP1030L by Saint Gobain Ceramics, UHP-1010 by Carborundum, Ronaflair Extender by Merck, Covalumine Atlas White AS by Sensient, Boroneige 601 by ESK, PUHP3008 by Saint Gobain Ceramics.

Clays are products that are already well known per se, which are described, for example, in the publication Minéralogie des argiles [Mineralogy of Clays] , S. Caillère, S. Hénin, M. Rautureau, 2nd Edition 1982, Masson.

Clays are silicates containing a cation that may be selected from calcium, magnesium, aluminium, sodium, potassium and lithium cations, and mixtures thereof.

Examples of such products that may be mentioned include clays of the smectite family such as montmorillonites, hectorites, bentonites, beidellites and saponites, and also of the family of vermiculites, stevensite and chlorites.

The clays can be of natural or synthetic origin. Preferably, clays that are cosmetically compatible and acceptable with keratin fibres such as the hair are used.

The clay can be selected from montmorillonite, bentonite, hectorite, attapulgite, sepiolite and their mixtures. Preferably, the clay is a bentonite or a hectorite.

The clays may be selected from organophilic clays.

The organophilic clays are clays modified with a chemical compound selected from quaternary amines, tertiary amines, amine acetates, imidazolines, amine soaps, fatty sulfates, alkyl aryl sulfonates and amine oxides, and mixtures thereof.

Preferably, the organophilic clays according to the invention are clays modified with a chemical compound selected from quaternary amines.

Organophilic clays that may be mentioned include quaternium-18 bentonites such as those sold under the names Bentone 3, Bentone 38 and Bentone 38V by Elementis, Tixogel VP by United Catalyst, and Claytone 34, Claytone 40 and Claytone XL by Southern Clay; stearalkonium bentonites such as those sold under the names Bentone 27V by Elementis, Tixogel LG by United Catalyst, and Claytone AF and Claytone APA by Southern Clay and quaternium-18/benzalkonium bentonites such as those sold under the names Claytone HT and Claytone PS by Southern Clay.

The organophilic clay is particularly selected from modified hectorites such as the hectorite modified by C ₁₀-C ₁₂ fatty acid ammonium chloride, especially distearyldimethylammonium chloride and stearylbenzyldimethylammonium chloride.

The clays are especially selected from montmorillonites and kaolin.

Particularly preferred particles that absorb sebum are silica powders, especially silica powders especially precipitated and more specifically precipitated silica coated with wax, boron nitride, acrylic polymer powders.

Preferably, the particles have a number-average size of between 50 nm and 350 microns, better still between 100 nm and 100 microns and even more preferentially between 0.5 and 100 microns.

Fibre-based layer

According to the present invention, the fibre-based layer (s) can be all fibre-based layers that can efficiently absorb the actives out from the hydrogel and deliver to the skin.

The fibre-based layer (s) used in the present invention comprises a compound (e.g. salt (s) of fibre, for example, calcium alginate etc. ) that is capable of reacting with the water soluble alkali metal salt (e.g. EDTA disodium salt or sodium citrate etc. ) included in the hydrogel layer to form an alkali metal salt (e.g. sodium alginate) , wherein the obtained alkali metal salt is a hydrophilic substance. The obtained hydrophilic alkali metal salt thus can absorb water and/or aqueous substances including water-soluble components therein from the hydrogel layer, such that the water and water-soluble components in the gel are continuously transferred out of the gel into the fibre-based layer. Thus, the fibre-based layer delivers the water and water-soluble components to the keratin materials, particularly skin.

The present invention relates to a sheet of the fibre-based layer. As the fibre-based layer is used as a part of the sheet, the material of the fibre-based layer is one that can absorb the actives out from the hydrogel and deliver to the skin, wherein the fibre-based layer is based on at least one of the followings selected from natural, man-made natural and/or synthetic fibre that can be all fibre-based layers that can efficiently absorb the actives out from the hydrogel and deliver to the skin, for example, natural (bio-) cellulose fibers or manufactured (bio-) cellulose fibre, preferably, based on alginate fibre and cellulose fibres, its mixture thereof. Two or more selected from the above substances may be used in combination.

In one embodiment of the present invention, preferably, the fibre-based layer is based on alginate fibre and other fibres.

In one embodiment of the present invention, preferably, the fibre-based layer is based on alginate fibre and cellulose fibres.

In one embodiment of the present invention, the compound used in the fibre-based layer (s) that is capable of reacting with the water soluble alkali metal salt included in the hydrogel layer is a divalent salt of fibre, for example, calcium alginate.

In one embodiment of the present invention, the weight of the fibre-based layer ranges from 18g/m ² to 60g/m ².

In one embodiment of the present invention, the fibre-based layer is an alginate-based layer, comprising from 0.1wt. %-50wt. %of calcium alginate fibre with 50wt. %-99.9wt. %of at least one another cellulose fibre, related to the total weight of the composition.

In one embodiment, the present fibre-based layer (preferably, alginate-based layer) can efficiently absorb the actives out from the hydrogel and deliver to the keratin materials, particularly skin. The present fibre-based layer (preferably, alginate-based layer) has an excellent delivery capability when applying on the keratin materials, particularly skin.

Mask

According to the present invention, the present fibre-based layer is coated on the hydrogel layer, and the present fibre-based layer can help the actives delivered out from the hydrogel such that the mask highly improve the delivery capacity of hydrogel type mask, and make the hydrogel layer from the "support material" into a real functional layer.

The folded mask according to the present invention may be made of two or more layers. Thus, for example, the mask may comprise two or more stacked layers. If a layered mask is used, the material of each stacked layer may be same as or different from each other. For example, the layered mask may be prepared by laminating the above layer (s) or sheet, for example, by hot coating process.

The mask can be made into a wide variety of shapes and forms such as flat pads, thick pads, thin sheets of irregular thickness, depending on the desired use and characteristic of the mask. The mask is typically designed to fit the area of the keratin materials (particularly, the skin, and more preferably the facial skin) to which topical application is desired. For example, when the mask is applied to the face, it is designed to correspond to the shape of the face avoiding the eye, nostril, and mouth areas, as necessary.

The weight ratio of the hydrogel layer to the fibre-based layercoated on the hydrogel layer is between 99: 1 to 80: 20, preferably, between 99: 1 to 80:15, or between 99: 1 to 85: 15, or even between 98: 2 to 90: 10.

In one embodiment, in the present mask, the fibre-based layer (as a primer layer, i.e. a lowest layer) is the layer that directly contacts with keratin materials.

In view of the presence of active agent and hydrophilic substances that are benefit for the keratin materials (e.g. the skin) in the hydrogel layer, the mask of the present invention showed a tremendous improvement on high loaded amount of actives and hydrophilic substances, i.e., the mask of the present invention loads more actives and hydrophilic substances so as to efficiently provide them to the keratin materials (e.g. the skin) and shows good skin conditioning effect, such as moisturizing, freshness, smoothness, softness effect and for a long term of using.

Active agents

According to an embodiment of the present invention, the mask the present invention may comprise at least one functional agent (called active agent or actives) , such as, at least one active agent (preferably, added in the hydrogel layer) , for example, chosen from: drugs; desquamating or moisturizing agents; depigmenting or anti-depigmenting agents; anti-glycation agents; anti-NO agents; agents for stimulating the synthesis of dermal or epidermal macromolecules and/or for preventing their degradation; agents for stimulating fibroblast or keratinocyte proliferation and/or keratinocyte differentiation; muscle relaxants or dermo-decontracting agents; free-radical scavengers or anti-pollution agents; tensioning agents; agents acting on the capillary circulation; certainly, the following particularly active agents, and mixtures thereof.

Amongst all of the active agents that can be used in the present invention, particular mention can be made of: α-orβ-hydroxy acids such as lactic acid, glycolic acid, citric acid, 5-octanoylsalicyclic acid, α-hydroxydecanoic acid, α-hydroxylauric, tartaric acid, glucuronic acid, galacturonic acid, acrylic acid, α-hydroxybutyric acid, α-hydroxyisobutyric acid, malic acid, mandelic acid, phosphoric acid, pyruvic acid, lactobionic acid, and salicylic acid.

It is also possible to use anti-acne agents, such as salicylic acid or benzoyl peroxide, octopirox, dextrorotary and levorotary sulfur-containing amino acids, their salts, and their N-acetyl derivatives such as N-acetyl cysteine, or agents seeking to prevent aging of the skin and/or to improve its state, for example the above-mentionedα-andβ-hydroxy acids, retinoids such as retinoic acid, retinol, and its esters, such as, for example, retinyl propionate, and retinyl acetate, or retinyl palmitate, niacinamide, allantoin, extracts of aloe, azelaic acid, bisabolol, phytic acid, collagen, or agents stimulating the formation of collagen, vitamins such as vitamin C or derivatives thereof, such as ascorbyl glucoside, vitamin E or derivatives thereof, vitamin A or derivatives thereof, vitamin F or derivatives thereof, dextrorotary and levorotary sulfur-containing amino acids and derivatives thereof as mentioned above, elastin, N-acetyl D-glucosamine, luteolin, or antioxidants such as green tea or active fractions thereof, glycerin, laponite, caffeine, essential aromatic oils, coloring agents, free-radical scavengers, moisturizers, depigmenting agents, agents for improving the color of the skin such as artificial-tanning agents of the dihydroxyacetone or tyrosin ester type, liporegulators, softeners, anti-wrinkle agents, keratolytic agents, fresheners, deodorants, anesthetics, nourishing agents, and mixtures thereof. It is also possible to use bleaching agents such as kojic acid, ascorbyl phosphates, ascorbyl glucosides, ascorbic acid, and mixtures thereof.

It is also possible to use active agents for improving the condition of the skin in the case of mask, such as moisturizers or agents serving to improve the natural lipid barrier, such as ceramides, cholesterol sulfates, and/or fatty acids, and mixtures thereof. It is also possible to use enzymes that have activity on the skin, such as proteases, lipases, cerebrosidases, and/or melanases, and mixtures thereof.

As other examples of active agents that can be suitable for implementing the present invention there are agents for drugs, peptides, proteins, detectable labels, contrast reagents, pain-killing, anesthetics, antibacterial agents, anti-yeast agents, antifungal agents, antiviral agents, anti-dermititis agents, anti-pruritic agents, anti-emetics, vascular protectors, agents against motion sickness, anti-irritants, anti-inflammatory agents, immunomodulators, anti-hyperkeratolytic agents, agents for treating dry skin, antiperspirants, anti-psoriatic agents, antidandruff agents, anti-aging agents, anti-asthmatic agents and bronchodilators, sunscreen agents, antihistamines, healing agents, corticosteroids, tanning agents, and mixtures thereof.

The content of the at least one active agent in the first composition and/or in the second composition may be adjusted as a function of the intended purpose of the mask.

Adjuvants

In a known manner, the mask of the present invention may also contain adjuvants that are common in cosmetics and/or dermatology, such as preserving agents, antioxidants, pH modifiers (acidic or basic) , fragrances, fillers, bactericides, odour absorbers, colorants (pigments and dyes) , emulsifiers, and also lipid vesicles.

Needless to say, a person skilled in the art will take care to select this or these optional additional compound (s) , and/or the amount thereof, such that the benefits of the second composition according to the present invention are not, or are not substantially, adversely affected by the envisaged addition.

Method and use

The mask or a skin wound dressing according to the present invention can be prepared comprising the following steps:

- (1) providing a fibre-based layer; and

- (2) providing a hydrogel layer comprising active agent (s) ,

- (3) coating the fibre-based layer on the hydrogel layer.

According to an embodiment, the step (3) coating the fibre-based layer on the hydrogel layer is carried out by the hot coating process.

According to an embodiment, the mask according to the present invention is prepared by the process comprising the following steps:

- Fixing the tissue on a roll, and one end is inserted between the 2 pressing rolls,

- Keeping the hydrogel in the tank at the temperature 50-70℃,

- Dripping the hot fluid hydrogel bulk on top of the tissue,

- Fixing the 2 rolls distance at 0.1-0.2cm,

- Compressing and cooled the hydrogel layer with the 2 pressing rolls with cooling system,

- Die-cutting the final mask into a face shape (normally 300-350cm ² with eye, nose and mouth holes) .

According to an embodiment, the mask according to the present invention can be used for caring for keratin materials, preferably the skin, and more preferably the facial skin; and also can be used for managing skin wound, for preventing post-surgical adhesion formation, or for filling or repairing osteochondral defects, and so on. This use may manifest itself as a process for managing skin wound, for preventing post-surgical adhesion formation, or for filling or repairing osteochondral defects, comprising applying the present mask or the present skin wound dressing of the present invention to a location in need.

Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the present invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contain certain errors necessarily resulting from the standard deviation found in their respective measurements. The following examples are intended to illustrate the present invention without limiting the scope as a result.

The examples that follow are aimed at illustrating the compositions and processes according to this invention, but are not in any way a limitation of the scope of the invention. All the parts and percentages in the examples are given on a weight basis and all the measurements were obtained at about 25℃, unless otherwise mentioned.

DESCRIPTION OF DRAWINGS

The figure 1 shows the coating process during preparing the present mask.

EXAMPLES

Example1: Preparation of Fibre-based layer

Protocol of preparation:

The alginate-based layer was prepared by the fibre that was available from Eastex company under the name E8080142 (20 wt. %calcium alginate, 80 wt. %cellulose, tissue density was 40g/m ²) .

Example2: Preparation of Hydrogel layer

Protocol of preparation:

The formulae of the hydrogel layer were as followings:

PROCESS:

1. Added all the ingredients into a baker

2. Heated the mixture into 70-80℃, mixed until all the ingredients well dissolved

3. Stopped mix, kept the mixture in the 80-85℃.

4. Cooled into room temperature.

Example3: Preparation of Mask

The alginate-based layer as above was tightly contact with the hydrogel layer obtained as above by hot coating process.

Protocol of preparation:

The coating process was presented as below picture shown in the Figure 1.

PROCESS:

1. Fixed the tissue on a roll, and one end is inserted between the 2 pressing rolls,

2. Kept the hydrogel in the tank at the temperature 50-60℃,

3. Dripped the hot fluid hydrogel bulk on top of the tissue,

4. Fixed the 2 rolls distance at 0.1-0.2cm,

5. Compressed and cooled the hydrogel layer with the 2 pressing rolls with cooling system,

6. Die-cut the final mask into a face shape (normally 300-350cm ² with eye, nose and mouth holes) .

Comparative Examples: (5*5cm ²tissue) preparation

Following examples were prepared:

1. Comparative Example 1:

The masks of Comparative Example 1 were prepared by coating the hydrogel layer on top of the alginate-based layer (the hydrogel layer formula and the composition of alginate base layer are as following)

Formula 1

INCI	%of weight
Niacinamide	0
caffeine	2.5
Xanthan gum	0.2
Carrageenan	0.6
Glucomannan	0.4
Glycerin	8
Sodium citrate	1.5
water	Up to 100

Tissue 1

Component	%of weight
calcium alginate fiber	20
Cellulose fiber	80
Tissue weight	40g/m ²

Protocol of preparation:

2. Kept the hydrogel formula 1 in the tank at the temperature 60℃,

3. Dripped the hot fluid hydrogel bulk on top of the tissue,

4. Fixed the 2 rolls distance at 0.15cm,

6. Die-cutted the final mask into a small square shape (5*5 cm ² tissue) .

2. Comparative Example 2:

The masks of Comparative Example 2 were prepared by impregnate the alginate tissue with the following function formula.

Formula 2

INCI	%of weight
caffeine	2.5
Xanthan gum	0.5
Glycerin	8
Sodium citrate	1.5
water	Up to 100

Tissue 1

Component	%of weight
calcium alginate fibre	20
Cellulose fibre	80
Tissue weight	40g/m ²

Protocol of preparation:

1. Cutted the tissue into 5cm*5cm shape

2. Impregnated the small tissue into 2.5g juice

3. Lifted out the tissue.

3. Comparative Example 3:

The masks of Comparative Example 3 were prepared forming a hydrogel layer without a tissue layer, formula is the same with Example 1.

Formula 3

Protocol of preparation:

2. Kept the hydrogel formula 1 in the tank at the temperature 50-60℃,

3. Dripped the hot fluid hydrogel bulk on top of a plastic or steel plate,

4. Fixed the 2 rolls distance at 0.15cm,

6. Die-cutted the final mask into a small square shape (5*5 cm ²) .

Evaluation:

1. Delivery capability

Evaluation protocol:

- Mask (1) (the mask of the present invention) : coating 2.5g of hydrogel on top of the 20 wt. %alginate fiber; then Applied the alginate tissue side on a flat plate for 20 minutes (A) ; then Measured the total amount of the functional liquid residual on the plate.

Mask (2) (Comparative mask only including the alginate-based layer) : Provided the 2.5g of same functional liquid as shown in Table 1 to impregnate the alginate-based layer, then Applied the alginate tissue side on a flat plate for 20 minutes (A) ; then Measured the total amount of the functional liquid residual on the plate; and measured the active content residual on the plate

- Mask (3) (Comparative mask of only including the hydrogen layer) : making the hydrogel layer without alginate fiber, at the weight of 2.5g, then Applied the hydogel side on the plate for 20minuts (B) , then Measured the total amount of the functional liquid residual on the plate. measured the active content residual on the plate

- Mask (4) (Comparative mask using the hydrogel layer to deliver the actives) : coating 2.5g of hydrogel on top of the 20 wt. %alginate fiber; then Applied the hydrogel tissue side on a flat plate for 20 minutes (B) ; then Measured the total amount of the functional liquid residual on the plate; measured the active content residual on the plate

Evaluation result

The evaluation results were as shown in the table below.

The results showed that the delivering actives by Mask (1) (the mask of the present invention) was much greater than that of Masks (Comparative mask, not according to the present invention) .

2. Amount of functional liquid loading on the Mask

Evaluation protocol:

- Mask (1) (the mask of the present invention) : coating 33g hydrogel layer on top of alginate fiber, measure the weight of hydrogel loading on the alginate fiber

- Mask (2) (Comparative mask only including the alginate-based layer) : Merged the alginate tissue in the 33g functional liquid as shown in Table 1, lifted out, and measured the loaded amount of the functional liquid on the mask.

The evaluation results were as shown in the table below.

The result showed that the weight of functional liquid loaded on the Mask (2) was 28g; while the mask according to the present invention, had 33g functional liquid left on the mask.

Conclusion

Comparing to the prior art (only hydrogel layer or only alginate-based layer) , the mask of the present invention showed a tremendous improvement on high loaded amount of actives and good delivery capability, i.e., the mask of the present invention loads more actives so as to efficiently provide them to the skin and shows good skin conditioning effect, such as moisturizing, freshness, smoothness, softness effect and for a long term of using.

Claims

A mask for caring for keratin materials, comprising:

(1) at least one hydrogel layer,

(2) at least one fibre-based layer,

wherein one or more fibre-based layer is the layer that is closer to keratin materials after application than any hydrogel layer present in the mask.
The mask as claimed in claim 1, wherein the hydrogel layer (s) comprises water, at least one gel-forming composition, and at least one water soluble alkali metal salt.
The mask as claimed in any one of the preceding claims, wherein the gel-forming composition comprises at least one hydrophilic thickener, in particularly the hydrophilic thickener is selected from:

- anionic, cationic, amphoteric or nonionic chitin or chitosan polymers;

- cellulose polymers, in particular (C ₁-C ₃) hydroxyalkylcelluloses, selected from hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, hydroxymethylcellulose, ethylhydroxyethylcellulose, carboxymethylcellulose and quatemized derivatives of cellulose;

- vinyl polymers, for instance polyvinylpyrrolidones, copolymers of methyl vinyl ether and of malic anhydride, the copolymer of vinyl acetate and of crotonic acid, copolymers of vinylpyrrolidone and of vinyl acetate; copolymers of vinylpyrrolidone and of caprolactam; polyvinyl alcohol,

- optionally modified polymers of natural origin, such as galactomannans and derivatives thereof, for instance carrageen gum, konjac gum, gellan gum, locust bean gum, fenugreek gum, karaya gum, gum tragacanth, gum arabic, acacia gum, guar gum, carboxymethyl guar, hydroxypropyl guar, hydroxypropyl guar modified with sodium methylcarboxylate groups, xanthan gum and derivatives thereof;

- alginates and carrageenans, for example, carrageenans of the μ, κ, v, ι or λθ type, and mixtures thereof in all proportions, preferably κ type;

- mucopolysaccharides such as hyaluronic acid; and

- mixtures thereof.
The mask as claimed in any one of the preceding claims, wherein the water soluble alkali metal salt is selected EDTA disodium salt or sodium citrate.
The mask as claimed in any one of the preceding claims, wherein the hydrogel layer (s) comprises at least one active agent (s) .
The mask as claimed in claim 5, wherein the active agent is chosen from: agents for improving the condition of the keratin materials; drugs; anti-aging agents; anti-acne agents; desquamating or moisturizing agents; depigmenting or anti-depigmenting agents; anti-glycation agents; anti-NO agents; agents for stimulating the synthesis of dermal or epidermal macromolecules and/or for preventing their degradation; agents for stimulating fibroblast or keratinocyte proliferation and/or keratinocyte differentiation; muscle relaxants or dermo-decontracting agents; free-radical scavengers or anti-pollution agents; tensioning agents; agents acting on the capillary circulation.
The mask as claimed in any one of the preceding claims, wherein the fibre-based layer comprises a compound, for example divalent salt such as calcium alginate, which is capable of reacting with the water soluble alkali metal salt, such as EDTA disodium salt or sodium citrate, included in the hydrogel layer to form a hydrophilic alkali metal salt, such as sodium alginate.
The mask as claimed in any one of the preceding claims, wherein the fibre-based layer is the alginate-based layer, comprising from 0.1 wt. %-50 wt. %of calcium alginate fibre with 50 wt. %-99.9 wt. %cellulose fibre, related to the total weight of the composition.
The mask as claimed in any one of the preceding claims, wherein the keratin materials are the skin, and more preferably the facial skin.
A process for preparing the mask as claimed in any one of the preceding claims, comprising the following steps:

- providing a fibre-based layer;

- providing a hydrogel layer comprising active agent (s) ,

- coating the fibre-based layer on the hydrogel layer.
The process as claimed in claim 10, wherein the hydrogel layer is prepared by the substances comprising water, at least one gel-forming composition, at least one water soluble alkali metal salt.
The process as claimed in claim 10 or 11, wherein the step of coating the fibre-based layer on the hydrogel layer is carried out by the hot coating process.
The process as claimed in any one of claims 10 to 12, wherein the fibre-based layer is the alginate-based layer, which is preparing from 0.1 wt. %-50 wt. %of calcium alginate fibre with 50 wt. %-99.9 wt. %cellulose fibre.
Use of the mask as claimed in any one of the preceding claims 1 to 9 and of the mask obtained by the process as claimed in any one of the preceding claims 10 to 13, for caring for the keratin materials, preferably the skin, and more preferably the skin face, particularly, wherein at least one fibre-based layer is the layer that is closer to keratin materials than all hydrogel layer (s) present in the mask..
Non-therapeutic process involving use of the mask as claimed in any one of the preceding claims 1 to 9 and of the mask obtained by the process as claimed in any one of the preceding claims 10 to 13, wherein the fibre-based layer is applied to the keratin materials, preferably the skin, and more preferably the skin face, such that the fibre-based layer directly contacts with keratin materials, preferably the skin, and more preferably the skin face.