Aerosol dispensing system

• US 4,680,173 A
• Filed: 04/09/1981
• Issued: 07/14/1987
• Est. Priority Date: 04/28/1977
• Status: Expired due to Fees

• Current Assignee: Nicholas A. Mardesich
• Original Assignee: Nicholas A. Mardesich, Norman D. Burger
• Inventors: Burger, Norman D.
• Primary Examiner(s): ORE, DALE
• Application Number:
  US06/252,306
• Time in Patent Office: 2,287 Days
• Field of Search: 424/68, 424/47, 424/46, 424/66, 424/65
• US Class Current: 424/47
• CPC Class Codes: A61K 2800/413 Nanosized, i.e. having sizes below 100 nm
• CPC Class Codes: A61K 2800/526 Corrosion inhibitors
• CPC Class Codes: A61K 2800/87 Application Devices; Containers; Packaging
• CPC Class Codes: A61K 8/046 Aerosols; Foams
• CPC Class Codes: A61K 8/25 Silicon; Compounds thereof
• CPC Class Codes: A61Q 15/00 Anti-perspirants or body deodorants deodorisation of air A61L9/00
• CPC Class Codes: B82Y 5/00 Nanobiotechnology or nanomedicine, e.g. protein engineering or drug delivery
• CPC Class Codes: C09K 3/30 for aerosols aerosol containers B65D83/14

Abstract

An aerosol dispensing system includes a container having a valve-controlled opening for dispensing the container contents, which include hydrocarbon-adsorbent solids such as silica, hydrocarbon propellant adsorbed on such solids, and a weight ratio of hydrocarbon propellant to adsorbent solids ranging up to about 65 parts by weight of the contents, and a liquid composition that may include water, organic oils, alcohols, dispersed and dissolved metals, and metal salts.

Water-encapsulating silica permits use of water in aerosol compositions, but prevents mixing of water with other substances in the composition until the composition is dispensed as an aerosol.

Aerosol systems including containers with a valve-controlled opening and a valve for dispensing the container contents benefit from the addition of a capillary dip tube extending from the valve into the container contents where the contents are highly viscous. The capillary dip tube increases the velocity of the contents, and keeps them cohesive during movement through the tube.

Aerosol system containers having a valve-controlled opening and a vapor tap valve for dispensing the container contents permit the aerosol dispensing of flammable compositions at controlled rates with acceptable flame extensions by dispersing vapor in the product emerging from the valve opening.

Claims

1. In an aerosol system for dispensing an antiperspirant where the system includes a metal container having a valve-controlled spray, a valve for dispensing the contents thereof, and a dip tube extending from said valve to said container contents, a propellant for said system, and wherein said contents includes an anti-perspirant material such as the astringent salts of multi-valent cations, divalent astringent salts, trivalent astringent salts, tetravalent astringent salts and aluminum astringent salts, wherein said anti-perspirant material if dissolved in water forms a material corrosive with respect to the exposed metal of said container, the improvement comprising:

a super-hydrophobic powdered fumed silica having a particle size of between 0.007 microns and 15 nm, a surface area of from 120 m² /g to 225 m² /g as measured by the nitrogen adsorption, B.E.T., a bulk density of from 3 to 10 lbs./ft³,

said super-hydrophobic silica being present in an amount of up to about 5.5% by weight of the container contents,

water in an amount sufficient to increase the effectiveness of said anti-perspirant material, and

said super-hydrophobic fumed silica encapsulating at least said water to form a multiplicity of encapsulated drops whose outer surface is the fumed silica and whose contents include at least said water, thereby to prevent contact between said water and any exposed metal of said metal container.

2. In an aerosol system of claim 1 wherein said anti-perspirant is in solution with water and wherein said super-hydrophobic fumed silica encapsulates said solution to form a multiplicity of encapsulated drops whose outer surface is said fumed silica and whose contents include said solution.

3. In an aerosol system as set forth in claim 1 wherein said anti-perspirant material is aluminum chlorohydrate.

4. In an aerosol system for dispensing an antiperspirant where the system includes a metal container having a valve-controlled spray, a valve for dispensing the contents thereof, and a dip tube extending from said valve to said container contents, a propellant for said system, and wherein said contents includes an anti-perspirant material such as the astringent salts of multi-valent cations, divalent astringent salts, tetravalent astringent salts, trivalent astringent salts and aluminum astringent salts, wherein said anti-perspirant material if dissolved in water forms a material corrosive with respect to the exposed metal of said container, the improvement comprising:

a multiplicity of encapsulated droplets having a particle size of not greater than about 0.004 inches,

said droplets including an aqueous inner phase which if it contacts said anti-perspirant material will corrode any exposed metal of said container,

said droplets including an outer phase of particles of a super-hydrophobic fumed silica,

said outer phase operating to encapsulate said aqueous inner phase while said droplets are within said container and to rupture when said container contents are dispersed, and

said water being present in an amount sufficient to activate said anti-perspirant material.

5. In an aerosol system of claim 4 wherein said aqueous phase is water.

6. In an aerosol system of claim 4 wherein said aqueous phase is a solution of water and said anti-perspirant material.

7. In an aerosol system of claim 4 wherein said fumed silica has a particle size of between 0.007 microns and 15 nm.

8. In an aerosol system of claim 4 wherein water is present in an amount of 5.5% or less by weight of said contents.

9. In an aerosol system of claim 4 wherein the ratio of water to said fumed silica is between 10:

1 to 4;

1.

10. In an aerosol system of claim 4 wherein said fused silica has a bulk density of between 3 and 10 lbs./ft³.

11. A composition for use as an anti-perspirant and to be packaged in a container including exposed metal surfaces, said composition including as the essential ingredients:

a multiplicity of encapsulated droplets having a particle size of not greater than about 0.004 inches,

an anti-perspirant material which if contacted by water will corrode any exposed metal surfaces of said container,

said encapsulated droplets including an outer phase of a particulate super-hydrophobic fumed silica,

said fumed silica having a particle size of less than 0.007 microns, and

said encapsulated droplets including an inner phase of aqueous solution.

12. A composition as set forth in claim 11 wherein said inner phase is water and said outer phase prevents contact between said water and said anti-perspirant material.

13. A composition as set forth in claim 11 wherein said inner phase includes dissolved anti-perspirant material and said outer phase prevents said inner phase from contacting exposed metal.

14. A composition as set forth in claim 11 wherein said composition is in the form of a free-flowing dry powder.