Meta-stable insect repellent emulsion composition and method of use

• US 20060153891A1
• Filed: 03/09/2006
• Published: 07/13/2006
• Est. Priority Date: 12/26/2001
• Status: Abandoned Application

• Current Assignee: Andrew H. Pechko, Anthony D. Gonzalez, Vincent T. Polywoda
• Original Assignee: Andrew H. Pechko, Anthony D. Gonzalez, Vincent T. Polywoda
• Inventors: Gonzalez, Anthony D., Polywoda, Vincent T., Pechko, Andrew H.
• Application Number:
  US11/371,582
• Publication Number:
  US 20060153891A1
• Time in Patent Office: Days
• US Class Current: 424/405
• CPC Class Codes: A01N 2300/00 Combinations or mixtures of active ingredients covered by classes A01N27/00 - A01N65/48 with other active or formulation relevant ingredients, e.g. specific carrier materials or surfactants, covered by classes A01N25/00 - A01N65/48
• CPC Class Codes: A01N 25/02 containing liquids as carriers, diluents or solvents
• CPC Class Codes: A01N 25/04 Dispersions, emulsions, suspoemulsions, suspension concentrates or gels foams A01N25/16
• CPC Class Codes: A01N 31/02 Acyclic compounds
• CPC Class Codes: A01N 37/18 containing the group —CO—N<, e.g. carboxylic acid amides or imides; Thio analogues thereof
• CPC Class Codes: A01N 37/22 the nitrogen atom being directly attached to an aromatic ring system, e.g. anilides
• CPC Class Codes: A01N 37/46 N-acyl derivatives
• CPC Class Codes: A01N 43/16 with oxygen as the ring hetero atom
• CPC Class Codes: A01N 43/30 with two oxygen atoms in positions 1,3, condensed with a carbocyclic ring
• CPC Class Codes: A01N 49/00 Biocides, pest repellants or attractants, or plant growth regulators, containing compounds containing the group , wherein m+n>=1, both X together may also mean —Y— or a direct carbon-to-carbon bond, and the carbon atoms marked with an asterisk are not part of any ring system other than that which may be formed by the atoms X, the carbon atoms in square brackets being part of any acyclic or cyclic structure, or the group , wherein A means a carbon atom or Y, n>=0, and not more than one of these carbon atoms being a member of the same ring system, e.g. juvenile insect hormones or mimics thereof containing hydrocarbons A01N27/00
• CPC Class Codes: A01N 65/00 Biocides, pest repellants or attractants, or plant growth regulators containing material from algae, lichens, bryophyta, multi-cellular fungi or plants, or extracts thereof containing compounds of determined constitution A01N27/00 - A01N59/00
• CPC Class Codes: A01N 65/08 Magnoliopsida [dicotyledons]
• CPC Class Codes: A01N 65/12 Asteraceae or Compositae [Aster or Sunflower family], e.g. daisy, pyrethrum, artichoke, lettuce, sunflower, wormwood or tarragon
• CPC Class Codes: A01N 65/28 Myrtaceae [Myrtle family], e.g. teatree or clove
• CPC Class Codes: A01N 65/42 Aloeaceae [Aloe family] or Liliaceae [Lily family], e.g. aloe, veratrum, onion, garlic or chives
• CPC Class Codes: A01N 65/44 Poaceae or Gramineae [Grass family], e.g. bamboo, lemon grass or citronella grass
• CPC Class Codes: A61K 8/06 Emulsions
• CPC Class Codes: A61K 8/066 Multiple emulsions, e.g. water-in-oil-in-water
• CPC Class Codes: A61Q 17/04 Topical preparations for affording protection against sunlight or other radiation; Topical sun tanning preparations
• CPC Class Codes: Y02A 50/30 Against vector-borne diseases, e.g. mosquito-borne, fly-borne, tick-borne or waterborne diseases whose impact is exacerbated by climate change

Abstract

There is provided an improved insect repellent emulsion composition. The composition has an inner discontinuous phase and an outer continuous phase. The inner discontinuous phase and/or outer continuous phase has an insect repellent active therein. The inner discontinuous phase is generally dispersed in the outer continuous phase and is in the form of discrete droplets having a multimodal droplet size distribution. There is also provided a method of protecting skin from being bitten by insects in which the above composition is applied topically to the skin. There is also provided a method of enhancing the performance of a insect repellent emulsion by forming the inner discontinuous phase as a multiplicity of droplets having a multimodal droplet size distribution. There is also provided a method of preparing an emulsifier-free insect repellent composition.

Claims

1-27. -27. (canceled)

28. An emulsion composition for topical application to skin, comprising:

an insect repellent active;

an inner discontinuous phase comprised of a plurality of droplets;

an outer continuous phase; and

an amount of an emulsifying agent, or emulsifying agent and co-solvent, sufficient to produce in the inner discontinuous phase a multimodal droplet size distribution of the plurality of droplets so that the composition is meta-stable and when applied to the skin has a faster onset or longer period of insect repellent effect compared to application of a like amount of a like composition that is not meta-stable.

50. A method of enhancing the insect repellent performance of a composition containing an insect repellent active, comprising adding to the composition an emulsifying agent, a co-solvent, or a mixture of an emulsifying agent and co-solvent, and forming an emulsion having an inner discontinuous phase comprised of a plurality of droplets and an outer continuous phase, adjusting the amount of emulsifying agent, co-solvent, or mixture of emulsifier and co-solvent, that is added to such amount that will produce a multimodal distribution of the plurality of droplets so that the composition is meta-stable and when applied to skin exhibits an enhanced insect repellent performance as compared to application of a like amount of a like composition that is not meta-stable.

51. A method of preparing an insect repellent emulsion composition, comprising:

combining an insect repellent active with a co-solvent, an emulsifying agent, or a co-solvent and emulsifying agent, to form a mixture;

forming an emulsion having an inner discontinuous phase and an outer continuous phase;

introducing the mixture into the emulsion; and

adjusting the amount of emulsifying agent, the amount of co-solvent, or the relative amounts of the emulsifying agent and co-solvent, so that the inner discontinuous phase is dispersed in the continuous phase as a plurality of droplets in a multimodal droplet distribution and the composition when applied to skin exhibits a faster onset of insect repellent effect or a longer period of insect repellent effect, compared to application of a like amount of a like composition that is not meta-stable.