AEROGELS AND THEIR USE IN COSMETIC APPLICATIONS

Abstract

The present invention relates to a cosmetic and/or dermatological composition comprising, in a physiologically acceptable medium aerogel particles comprising an alginate, as well as the cosmetic use of a cosmetic and/or dermatological composition comprising, in a physiologically acceptable medium aerogel particles comprising an alginate, for treating the skin.

Claims

1. A cosmetic and/or dermatological composition comprising, in a physiologically acceptable medium, aerogel particles comprising an alginate.

2. The composition according to claim 1, wherein the aerogel particles have a bulk density in the range of from 0.03 to 1 kg/m.sup.3.

3. The composition according to claim 1, wherein the aerogel has a degree of cross-linking in the range of from 0.5 to 2.

4. The composition according to claim 1, wherein the aerogel comprises one or more further polysaccharide.

5. The composition according to claim 1, wherein the aerogel is obtained by a process for preparing a porous material, comprising: a) providing a mixture (I) comprising (i) a water soluble alginate, (ii) at least one compound suitable to react as cross-linker for the alginate or to release a cross-linker for the alginate, (iii) water, b) preparing a gel (A) comprising steps b1) and b2) b1) exposing mixture (I) to carbon dioxide at a pressure in the range of from 20 to 100 bar for a time sufficient to form a gel (A), and b2) depressurizing the gel (A), c) exposing the gel (A) obtained in step b) to a water miscible solvent (L) to obtain a gel (B), d) drying of the gel (B) obtained in step c).

6. The composition according to claim 1, wherein a volume average pore diameter of the aerogel is not more than 4 microns.

7. The composition according to claim 1, wherein a volume average pore diameter of the aerogel particles is at least 20 nm.

8. The composition according to claim 1, wherein the aerogel has a porosity of at least 70% by volume.

9. The composition according to claim 1, wherein the aerogel is present in the composition in an amount in the range of from 0.02 to 10% by weight, based on the total weight of the composition.

10. The composition according to claim 1, wherein the composition comprises at least one aqueous phase.

11. The composition according to claim 1, for use in treating the skin.

12. The composition according to claim 7, wherein the average pore diameter of the aerogel particles is at least 50 nm.

13. The composition according to claim 8, wherein the aerogel has a porosity of 70 to 99% by volume.

14. The composition according to claim 9, wherein the aerogel is present in the composition in an amount from 0.02 to 0.5% by weight-based on the total weight of the composition.

Description

EXAMPLES

[0154] 1. Preparation of Water Soluble Films from Aerogel

1.1 Cold Process

[0155] The required amount of Aerogel will be given to VE-water while stirring. The aerogels directly start swelling. After 5 min. of additional stirring, a homogenization with an Ultra Turax is recommended. The ph-value can be adjusted as required with citric acid or another cosmetically acceptable pH adjusting agent.

[0156] The prepared aqueous Aerogel will be now poured out of a smooth surface in the required thickness. After drying at low temperatures, strong inflexible films are formed.

[0157] With water contact the product starts to swell again and return to gel.

TABLE-US-00001 TABLE 1 Basic test formulation for skin care % by Phase Ingredients INCI weight Function A Eumulgin SG Sodium Stearoyl 1.00 Emulsifier Glutamate (O/W) Cutina HVG Hydrogenated 5.00 Consistency Vegetable Glycerides agent Cetiol LC Coco-Caprylate/Caprate 16.00 Emollient B Aerogel Ca-Alginat 0.75 Water, demin. 78.00 C Euxyl K 320 1.00 Preservative citric acid q.s. pH adjustment

1.2 Manufacturing Process

[0158] Heat phase A and phase B separately up to 85 C. Add phase B to phase A while stirring.

[0159] Stir in such a way that it remains in continual motion. Avoid the incorporation of air. Homogenize at 55 C. by means of a suitable dispersion unit (e.g. Ultra Turrax) in order to improve stability and structure.

[0160] Cool to 40 C. and add components of phase C one by one while stirring.

[0161] Finally adjust the pH-value to approx. 6.5. Stop stirring at 30 C. to give a smooth emulsion with a Brookfield viscosity of 65000 mPa*s measured with Brookfield Helipath and spindle 94 at 4 rpm.

TABLE-US-00002 Eumulgin SG 1.0 Cutina HVG 1.0 Lanette O 3.0 Myritol 331 6.0 Cetiol LC 3.0 preservative q.s. Glycerin 5.0 Water ad 100

TABLE-US-00003 TABLE 2a Reference 5 1 2 3 Variation Placebo 1% . . . 13 0.75% . . . 14 1.0% . . . 13 Oil phase Oil phase Water phase Viscosity 62.500 137.500 75.000 162.500 (mPas) (Brookfield RVF, TE-spindle, 4 rpm, Helipath) pH-value 7.4 7.2 7.6 7.1 Macro B C B C Micro Evenly Partly Evenly Evenly homogeneous, crystalline homogeneous homogeneous relatively structures, large oil drops relatively evenly appearance foamy slimy/ smooth slimy, like inhomogeneous GTC Stability/ RT and 5 C. Do not look 5 C., RT, 40 C. stabel good 40 C. 12 weeks Stability/ 4 weeks, 4 weeks, 8 weeks, 12 weeks, separated 45 C. 50 C. 50 C. 50 C. 8 weeks, 40, 50 C. viscosity after 37.500 137.500 100.000 187.500 12 weeks/RT (mPas) (Brookfield RVF, TE-spindle, 4 rpm, Helipath)

TABLE-US-00004 TABLE 2b Reference 4 6 7 8 9 Variation 1.0% . . . 14 0.3% . . . 13 2.0% . . . 13 0.3% . . . 14 2.0% . . . 14 water phase water phase water phase Water phase Water phase Viscosity 175.000 137.500 325.000 112.500 300.000 (mPas) (Brookfield RVF, TE- spindle, 4 rpm, Helipath) pH-value 7.5 7.6 7.6 7.8 7.9 Macro C B-C C B-C C Micro Evenly Evenly Lamellar Evenly Lamellar homogeneous homogeneous structures, homogeneous structures, large and large and uneven uneven appearance slimy, like smooth extremely smooth extremely GTC ,,griesig ,,griesig Stability/ 5 C. 5 C., RT, Not stored 5 C., RT, Not stabel 12 40 C. 40 C. stored weeks Stability/ 12 weeks, 2 weeks, 2 weeks, separated 50 C. 50 C. 50 C. 12 weeks, 4 weeks, 45 C. 45 C. viscosity after 200.000 87.500 87.500 12 weeks/RT (mPas) (Brookfield RVF, TE- spindle, 4 rpm, Helipath)

LITERATURE CITED

[0162] WO 2013/190104 A2 [0163] US 2015/0190319 A1 [0164] WO 2015/177081 A1 [0165] EP-A-251905 [0166] Alginic Acid in Rompp Chemie Lexikon Naturstoffe (Encyclopedia of Natural Products), Thieme Verlag, 1997 [0167] WO 2015/177081 A1