Polynuclear Microcapsules

• US 20100172999A1
• Filed: 12/21/2007
• Published: 07/08/2010
• Est. Priority Date: 12/28/2006
• Status: Active Grant

• Current Assignee: Dow Silicones Corporation (Dow, Inc.)
• Original Assignee: Dow Corning Corporation (Dow, Inc.)
• Inventors: Marteaux, Leon Andre, Zimmerman, Brett Lee
• Granted Patent: US 8,435,560 B2
• Time in Patent Office: Days
• US Class Current: 424/490
• CPC Class Codes: A45C 11/00 Receptacles for purposes not provided for in groups A45C1/00-A45C9/00 specially adapted for toiletry or cosmetic equipment A45D29/20, A45D44/18; travelling sewing kits A45F3/48
• CPC Class Codes: A45C 13/26 Special adaptations of handles A45C13/22 takes precedence
• CPC Class Codes: A45C 2011/001 for portable audio devices, e.g. headphones or MP3-players
• CPC Class Codes: A45C 2011/003 for portable computing devices, e.g. laptop, tablet, netbook, game boy, navigation system, calculator
• CPC Class Codes: A45F 2005/026 with a pin having an enlarged head detachably connected to a fastening device, e.g. to a pin receiving slot
• CPC Class Codes: A45F 2200/0508 Portable audio devices, e.g. walkman, discman, radio, MP3 player, headphones
• CPC Class Codes: A45F 2200/0516 Portable handheld communication devices, e.g. mobile phone, pager, beeper, PDA, smart phone
• CPC Class Codes: A45F 5/02 Fastening articles to the garment
• CPC Class Codes: A45F 5/021 to the belt
• CPC Class Codes: A61K 9/501 Inorganic compounds
• CPC Class Codes: A61K 9/5089 Processes
• CPC Class Codes: Y10S 224/93 Attached to animate bearer

Abstract

A process is disclosed for preparing polynuclear microcapsules by polymerizing an alkoxysilane at the oil/water interface of a multiple phase emulsion to form a suspension of polynuclear microcapsules. Also disclosed are polynuclear micro-capsules optionally comprising a hydrophilic active and uses thereof.

Claims

1. A polynuclear microcapsule which comprises an outer-capsule wherein the outer-capsule comprises an outer-shell and a plurality of inner-capsules, wherein each of the inner-capsules comprises an inner-shell and an aqueous phase core, wherein the outer-shell and the inner-shell further comprise a silica or an organofunctional silica.

2. The polynuclear microcapsule of claim 1 wherein the silica or organofunctional silica comprises a reaction product from the polymerization of an alkoxysilane or a mixture of alkoxysilanes at the oil/water interfaces of a multiple phase emulsion.

3. The polynuclear microcapsule of claim 1 wherein the aqueous phase core comprises a hydrophilic active.

4. The polynuclear microcapsule of claim 2 wherein the aqueous phase core comprises a hydrophilic active.

5. The polynuclear microcapsule of claim 3 wherein the alkoxysilane is tetraethoxysilane.

6. The polynuclear microcapsule of claim 3 wherein the weight percent of the hydrophilic active is between 0.01 percent and 90 percent.

7. The polynuclear microcapsule of claim 6, wherein the hydrophilic active comprises a drug, a vitamin, a sunscreen agent, a colorant, a metaloxide, or a biologic.

8. The polynuclear microcapsule of claim 7 wherein the biologic is an enzyme.

9. The polynuclear microcapsule of any one of claim 3 wherein the polynuclear microcapsule has an average volume particle size of between 0.5 micrometers and 1000 micrometers.

10. The polynuclear microcapsule of any one of claim 3 wherein the average volume particle size is between 0.5 micrometers and 20 micrometers.

11. The polynuclear microcapsule of any one of claim 3 wherein the average volume particle size is between 10 and 500 micrometers.

12. The use of the polynuclear microcapsule of claim 1 for the entrapment of biologic.

13. The use of the polynuclear microcapsule of claim 1 for the stabilization of a biologic.

14. A composition comprising a polynuclear microcapsule of claim 1 and at least one pharmaceutically-acceptable carrier, adjuvant or diluent.

15. A process for preparing a suspension of polynuclear microcapsules of claim 1 comprising the following steps:

I) mixing

A) a first emulsifier,

B) an alkoxysilane,

C) a hydrophilic active,

with water to form an emulsion having a continuous phase and a disperse phase wherein the alkoxysilane is in the continuous phase;

II) admixing to the emulsion having the alkoxysilane in the continuous phase

D) a second emulsifier

to form a multiple phase emulsion having multiple oil/water interfaces; and

III) polymerizing the alkoxysilane at the oil/water interfaces of the multiple phase emulsion to form the suspension of polynuclear microcapsules.

16. The process of claim 15 further comprising the step of recovering the polynuclear microcapsules from the suspension.

17. The process of claim 15 wherein the first emulsifier comprises a silicone polyether having the formula I or II:

wherein R1 is a (C₁-C₆) alkyl group,

x is an integer of 1-1,000, y is an integer of 1-500, z is an integer of 1-500,

R2 represents the group —

(CH₂)_aO(C₂H₄O)_b(C₃H₆O)_cR3;

a is an integer of 3-6;

b is an integer of 1-40;

c is an integer of 0-40; and

R3 is hydrogen, a methyl group, or an acyl group.

18. The process of claim 15 wherein the alkoxysilane is tetraalkoxysilane.

19. The process of claim 15 wherein the second emulsifier is a cationic surfactant, a non-ionic surfactant, amphoteric surfactant, or any combination the surfactants.

20. The process of claim 15 wherein the second emulsifier is a polymeric surfactant or particle.

21. The process of claim 20 wherein the polymeric surfactant is an ethylene glycol propylene glycol copolymer.

22. The process of claim 20 wherein the particle is fumed silica, colloidal silica or synthetic clay.

23. The process of claim 15 wherein the weight percent of components A, B and C in step I range from;

A) 0.1 to 30 weight percent,

B) 1 to 99 weight percent,

C) 1 to 99 weight percent.

24. The process of claim 23 wherein the weight percent of component D ranges from 0.1 to 20 weight percent in the multiple phase emulsion of step II.

25. The process of claim 17 wherein x is 396, y is 4, a is 3, b is 18, c is 18 and d is 18.

26. The product produced using the process of claim 15.