Self-standing cosmetic sheet
The present invention relates to a cosmetic process which applies onto the skin a self-standing cosmetic sheet for the skin, comprising: ⋅at least one biocompatible and/or biodegradable hydrophobic polymer layer ⋅wherein ⋅the self-standing cosmetic sheet has a thickness of from 10 to 1000 nm, preferably from 30 to 500 nm, and more preferably from 50 to 300 nm. The cosmetic sheet according to the present invention may comprise at least one cosmetic active ingredient. The cosmetic sheet used in the present invention is very thin and not easily perceived on the skin; can be prepared with a variety of materials such as a biocompatible and/or biodegradable material, preferably non-cross-linked poly(lactic acid) or a combination of chitosan and alginic acid; and can adhere well onto the skin without any adhesive layer so that it is less irritable or no irritable to the skin.
1. A cosmetic process for the skin, the process comprising:
applying onto the skin a cosmetic sheet comprising at least one biocompatible and/or biodegradable hydrophobic polymer layer, and
changing the feel to touch of the skin, hiding the appearance of wrinkles and/or pores, and/or protecting the skin from pollution and/or contaminants,
wherein the cosmetic sheet is self-standing,
wherein the self-standing cosmetic sheet has a thickness ranging from about 50 nm to about 1000 nm, and
wherein the self-standing cosmetic sheet does not include a cosmetic active ingredient.
2. The cosmetic process according to claim 1 , wherein the at least one biocompatible and/or biodegradable hydrophobic polymer layer is non-cross-linked and is chosen from non-cross-linked poly(lactic acid) and derivatives thereof.
3. The cosmetic process according to claim 1 , wherein the at least one biocompatible and/or biodegradable hydrophobic polymer layer comprises at least one cationic polymer and at least one anionic polymer.
4. The cosmetic process according to claim 3 , wherein the at least one cationic polymer has at least one positively chargeable moiety chosen from quaternary ammonium groups, guanidine groups, biguanide groups, imidazole groups, imino groups, pyridyl groups, or amino groups.
5. The cosmetic process according to claim 4 , wherein the at least one cationic polymer is chosen from chitosan, collagen, polyallylamines, polyvinylamines, polydiallyldialkyl ammonium chloride, polyanilines, polyvinylimidazoles, polydimethylaminoethylenemethacrylates, poly-1-methyl-2-vinylpyridine, polyamines, polyimines, polyethyleneimines, polyvinylpyridines, poly(quaternary pyridine), polylysines, polyornithines, polyarginines, polyhistidines, polyaminopropyl biguanides, or salts thereof.
6. The cosmetic process according to claim 3 , wherein the anionic polymer has at least one negatively chargeable moiety chosen from sulfuric groups, sulfate groups, sulfonic groups, sulfonate groups, phosphoric groups, phosphate groups, phosphonic groups, phosphonate groups, carboxylic groups, or carboxylate groups.
7. The cosmetic process according to claim 6 , wherein the anionic polymer is chosen from alginic acid, hyaluronic acid, polyglutamic acids, polylactic acids, polyglycolic acids, polycaprolactones, poly(meth)acrylic acids, polyamic acids, polystyrene sulfonate, poly(vinyl sulfate), dextran sulfate, chondroitin sulfate, polymaleic acids, polyfumaric acids, carboxy methyl cellulose, styrene maleic anhydride derivatives or salts thereof.
8. The cosmetic process according to claim 1 , wherein the self-standing cosmetic sheet has a thickness of from about 50 nm to about 300 nm.