MICROCAPSULES COMPRISING BLACK PIGMENTS

• US 20140335138A1
• Filed: 05/16/2012
• Published: 11/13/2014
• Est. Priority Date: 05/16/2011
• Status: Active Grant

• Current Assignee: Tagra Biotechnologies Ltd. (EFAL Chemical Industries, Ltd.)
• Original Assignee: Tagra Biotechnologies Ltd. (EFAL Chemical Industries, Ltd.)
• Inventors: Goldstein, Danny, Privalova, Olga, Yasman, Yuri, Benaltabet, Lior
• Granted Patent: US 10,449,127 B2
• Time in Patent Office: Days
• US Class Current: 424/401
• CPC Class Codes: A61K 2800/412 Microsized, i.e. having sizes between 0.1 and 100 microns
• CPC Class Codes: A61K 2800/43 Pigments; Dyes
• CPC Class Codes: A61K 2800/624 by macromolecular compounds
• CPC Class Codes: A61K 2800/651 The particulate/core comprising inorganic material
• CPC Class Codes: A61K 8/0241 Containing particulates characterized by their shape and/or structure see also A61K8/04, A61K8/11, and A61K8/14, further aspects are classified in A61K2800/40 and subcodes
• CPC Class Codes: A61K 8/11 Encapsulated compositions
• CPC Class Codes: A61K 8/19 containing inorganic ingredients
• CPC Class Codes: A61K 8/731 Cellulose; Quaternized cellulose derivatives
• CPC Class Codes: A61K 8/8147 Homopolymers or copolymers of acids; Metal or ammonium salts thereof, e.g. crotonic acid, (meth)acrylic acid; Compositions of derivatives of such polymers
• CPC Class Codes: A61K 8/8152 Homopolymers or copolymers of esters, e.g. (meth)acrylic acid esters; Compositions of derivatives of such polymers
• CPC Class Codes: A61Q 1/02 Preparations containing skin colorants, e.g. pigments preparations in powder form A61Q1/12
• CPC Class Codes: A61Q 1/06 Lipsticks
• CPC Class Codes: A61Q 1/08 for cheeks, e.g. rouge
• CPC Class Codes: A61Q 1/10 for eyes, e.g. eyeliner, mascara
• CPC Class Codes: B01J 13/12 removing solvent from the wall-forming material solution
• CPC Class Codes: C01P 2004/52 highly monodisperse size distribution
• CPC Class Codes: C01P 2004/61 Micrometer sized, i.e. from 1-100 micrometer
• CPC Class Codes: C01P 2006/10 Solid density
• CPC Class Codes: C01P 2006/11 Powder tap density
• CPC Class Codes: C09C 1/0081 Composite particulate pigments or fillers, i.e. containing at least two solid phases, except those consisting of coated particles of one compound C09C1/0015, C09C1/0078 take precedence
• CPC Class Codes: C09C 1/24 : Oxides of iron
• CPC Class Codes: C09C 1/48 : Carbon black
• CPC Class Codes: C09C 1/56 : Treatment of carbon black ; Purification
• CPC Class Codes: C09C 3/10 : Treatment with macromolecular organic compounds C09C3/006 takes precedence

Abstract

Monolayered microcapsules comprising a black pigment and cosmetic formulations comprising them are provided for use particularly in mascara and eye liner formulations. The black pigment may be carbon black, black iron oxide, or both.

Claims

1. Monolayered microcapsules comprising a core of a black pigment and a shell of a wall-forming polymeric material selected from a polyacrylate, a polymethacrylate, a cellulose ether, a cellulose ester, or a combination thereof, wherein the microcapsules do not contain a plasticizer.

2. The microcapsules according to claim 1, wherein the black pigment is carbon black, black iron oxide, or a mixture thereof.

4. The microcapsules according to claim 2, wherein the black pigment is carbon black, and the amount of carbon black in the microcapsules is within a range selected from about 25 to about 95% by weight.

6. The microcapsules according to claim 2, wherein the black pigment is black iron oxide, and the amount of black iron oxide in the microcapsules is within a range selected from about 50 to about 95% by weight.

7. The microcapsules according to claim 1, wherein said microcapsules have a mean particle size within a range selected from about 1 to about 100 μ

m, about 1 to about 90 μ

m, about 1 to about 80 μ

m, about 1 to about 70 μ

m, 1 about to about 60 μ

m, about 1 to about 50 μ

m, about 30 to about 50 μ

m, about 34 to about 40 μ

m, about 1 to about 40 μ

m, about 1 to about 30 μ

m, about 1 to about 20 μ

m, about 1 to about 10 μ

m, about 1 to about 5 μ

m, or about 1 to about 3 μ

m.

9. The microcapsules of claim 2, wherein the black pigment is a mixture of carbon black and black iron oxide, and the ratio between the carbon black and black iron oxide in said mixture is in a range of from 1:

20 to 20;

1, respectively.

10. The microcapsules of claim 9, wherein said black pigment is in an amount from about 50 to about 90%, about 60 to about 90%, about 75 to about 90%, about 80 to about 90%, by weight.

11. The microcapsules according to claim 1, wherein said wall-forming material is poly(methyl methacrylate) co-methacrylic acid, ammonium methacrylate copolymer type B, cellulose ethyl ether, cellulose ethyl ester, or a combination thereof.

12. The microcapsules according to claim 11, wherein the wall-forming material is poly(methyl methacrylate) co-methacrylic acid or ammonium methacrylate copolymer type B and the amount of the polymer in the microcapsules is within a range selected from about 2 to about 50% by weight.

13. The microcapsules according to claim 12, wherein the black pigment is black iron oxide in an amount of about 90% or 95%, by weight, and the wall-forming material is ammonium methacrylate copolymer type B in an amount of about 5% or 10%, by weight.

14. The microcapsules according to claim 11, further comprising one or more additives.

17. The microcapsules according to claim 14, wherein the black pigment is carbon black in an amount of about 90%, by weight, the wall-forming material is poly(methyl methacrylate) co-methacrylic acid in an amount of about 2%, by weight, and the additive is butylene glycol cocoate, in an amount of about 10%, by weight.

18. The microcapsules according to claim 14, wherein the black pigment is black iron oxide in an amount of about 80%, by weight, the wall-forming material is ammonium methacrylate copolymer type B in an amount of about 10%, by weight, and the additive is hydrogenated polyisobutene in an amount of about 10%, by weight.

19. A method for the preparation of microcapsules according to claim 1, comprising:

a) preparing an organic solution of a black pigment with the wall-forming polymeric material in ethyl acetate, optionally in the presence of one or more additives, and subjecting the solution to homogenization or low shear mixing/stirring until a homogenate suspension is obtained;

b) mixing said homogenate suspension with an aqueous solution containing an emulsifier, under low or high shear stirring, to form an emulsion;

c) adding to the emulsion formed in (b) an excess amount of water to initiate extraction of the organic solvent from the emulsion, thus obtaining microcapsules;

d) optionally allowing sedimentation of the microcapsules; and

e) isolating said microcapsules of c) or d) by filtration, subsequently washing with water or with 10% alcohol, and optionally drying the wet capsules.

20. The method according to claim 19, wherein said low shear stirring in step a) or step b) ranges from 300 to 600 revolutions per minute (RPM);

and said high shear stirring in step b) ranges from 6000 to 12000 RPM.

21. The method according to claim 19, wherein the wall-forming polymeric material is poly(methyl methacrylate) co-methacrylic acid, ammonium methacrylate copolymer type B, cellulose ethyl ether, cellulose ethyl ester, or a combination thereof.

23. The method according to claim 19, wherein the steps of homogenization or mixing/stirring in step a) and stirring in step b) are carried out for no longer than 5 minutes.

24. A cosmetic formulation comprising black pigment microcapsules according to claim 1.

25. The cosmetic formulation according to claim 24, wherein the microcapsules are selected from:

(i) carbon black microcapsules;

(ii) black iron oxide microcapsules, (iii) microcapsules comprising a mixture of black iron oxide and carbon black, or (iv) a mixture of black iron oxide microcapsules and carbon black microcapsules.

26. The cosmetic formulation according to claim 25, which is a mascara, an eyeliner, an eye shadow, a lipstick, a blush, a makeup, a cream concealer, or a foundation for makeup formulation.

28. The cosmetic formulation according to claim 24, prepared by mixing the black pigment microcapsules with the other ingredients of the formulation and compressing the mixture.

3. (canceled)

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8. (canceled)

15-16. -16. (canceled)

22. (canceled)

27. (canceled)