GB2450727A

GB2450727A - Perfumed silicone microemulsion

Info

Publication number: GB2450727A
Application number: GB0712960A
Authority: GB
Inventors: Brian O'rourke; Arnold Alexander Stevenson
Original assignee: IRISH SKINCARE Ltd
Current assignee: IRISH SKINCARE Ltd
Priority date: 2007-07-05
Filing date: 2007-07-05
Publication date: 2009-01-07
Also published as: GB0712960D0

Abstract

Perfumed microemulsion compositions are disclosed which comprise at least one perfume oil incorporated into a (volatile) silicone compound. The microemulsion compositions of the present invention comprise: <SL> <LI>(i) at least one silicone compound; <LI>(ii) one or more perfume oils; and <LI>(iii) one or more emulsifiers </SL> substantially in the absence of water and/or alcohols such as ethanol wherein all three components are present and where the proportion of emulsifier(s) does not exceed 40% w/w.

Description

* 2o121 P12422GB 1

IMPROVEMENTS IN AND RELATING TO PERFUMED MICROEMULSION

COMPOSITIONS AND METHODS OF PRODUCING SAME

The present invention relates to improvements in and relating to perfumed microemulsiori composition and methods of producing same.

The term microemulsion was first introduced by Hoar & Schulman, (Nature, [1943] 329,309) to describe clear, isotropic emulsions which were found to form spontaneously in mixtures of oil, water and surfactant. Microemulsions, which were also known as transparent emulsions or swollen micelles, are thermodynamically-stable dispersions of oil in water or water in oil in which the droplet size is small enough to let light pass through. El-Nokaly and Fnberg (Cosmetics & Toiletries 97, 1982 p.55) have pointed out that normal' micelles allow for the incorporation of up to 10% solubilisate, whereas microemulsions may incorporate 30% and higher of the internal or solubilisate phase. Perfume microemulsions in water which are free from, or containing only traces of alcohol, are known in the prior art. J.M.

Blakeway et al, in particular (lnt. J. Cosmetic. Sci. 1 (1979), p1-15, described microemulsions of up to 4% w/w perfume in water with anionic surfactants such as sodium :.:::. lauryl ether sulphate and monoethanolamine lauryl sulphate in combination with non-ionic surfactants such as coconut diethanolamde. T.J. Lin, (Surfactants in Cosmetics, Surfactants Sci. Ser. Vol 16, (1985), 29-52), mentions the necessity of having a surfactant-to-oil ratio of much greater than unity to prepare practical 01w microemulsions.

Previous discussions of microemulsions have focussed primarily on mixtures containing water as either continuous or dispersed phase. Microemulsions using silicones as hydrophobic phase have recently become more common with such as the Dow Coming Corporation's DOW CORNING 1716 MICROEMULSION, which contains 1.0 -5.0% hexadecyltnmethylammonium chloride and 1.0 -5.0 Octamethylcyclotetrasiloxane in a translucent, 30% active, pourable cationic microemulsion of cross-linked OH polydimethylsiloxane internal phase'. For the purposes of the present invention the term, silicone microemulsion" shall encompass mixtures of silicone oils as continuous, non-polar phase and polar perfume oils with which the latter is immiscible, the mixtures also containing suitable surfactants and co-surfactants.

Throughout this specification, the term microemulsion will be understood to be refemng to a ccmplctcly-transparent system (i.e. no cloudiness or "milkiness").

Prior Art:

1. International Patent Publication No. WO 02/079121 Title: "Products for preventing penetration into the skin" This patent specification discloses cosmetic and/or dermatological compounds and compositions for the photoprotection of human skin and/or hair against the damaging effects of UV radiation, in particular solar radiation. In one embodiment, the specification discloses compositions and compounds for topical application comprising at least one :. photoprotective compound for topical application comprising hydroxylated derivatives of natural Jojoba oil or its synthetic substitute, estenfied with carboxylic acids or amino acids bearing UV-absorbing groups. * . * ...

2. United States Patent Specification No. US 5,585,343 Title: "Low volatile organic compound(s) (VOC) perfume formulations" * .. * * * S...

*:. 20 The specification discloses oil-in-water (01W) and water-in-oil (W/0) microemulsions of fragrance product formulations. The microemulsions are clear or at least translucent, sprayable, and non-sticky. Combinations of anionic surfactant components (a) and hydrophilic coactives (highly water soluble component (b) or a mixture of highly water soluble (b)(i) and less water soluble prior (b)(ii) components) are used to obtain fragrance product formulations that are free or substantially fee of ethanol.

3. United States Patent Specification No. US 5,374,614 Title: "Aqueous perfume oil microemulsions" The specification discloses clear 01w microemulsions comprising a perfume oil, an aqueous phase and one or more surfactants with HLB between 9 and 18, and co-surfactants of which at least 0.5% is ionic co-surfactant. The weight ratio of perfume oil to total surfactant is between 0.85 and 2.5, and preferably above 1. The quantity of perfume allis 0.01-40% wiw, preferably below 35%, of the microemulsions and the quantity of water at least 40% wiw, preferably at least 50%. The microemulsions comprise less than 10% preferably less than 5%, of alcohol. The surfactants are preferably of the nonionic type.

The microemulsions disclosed in US 5,374,614 are disclosed as being very suitable for perfuming purposes where the amount of organic solvents should preferably be kept to a minimum, such as for perfuming skin or hair.

The disclosure also concerns surfactantlperfume mixtures suitable for preparing the clear 0/w microemulsions. a * * * .*.

4. United States Patent Specification No. US 5,283,056 Title: Transparent oil-in-water microemulsions flavor or fragrance concentrate, :. process for preparing same, mouthwash or perfume composition containing said transparent microemulsion concentrate, and process for preparing same" : , The specification discloses a stable transparent oil-in-water microemulsion concentrate *. 20 consisting essentially of: (I) water; (ii) one or more hydrophobic flavour or perfume oils; and (iii) one or more surfactants wherein the mixing ratio of the water, oil and surfactant is, referring to FIG. 1A of the specification, within the range surrounded by the lines connecting points A, B and C of FIG. IA. Also described is a process for preparing the transparent microemulsion compositions.

Also described is a mouthwash containing acid transparent microemulsion compositions and a process for preparing same. Further disclosed is a perfume composition containing said transparent microemulsion compositions and the process for preparing same.

5. United States Patent Specification No. US 5,320,863 This patent ws divided out of Patent No. 5,283,056 (indicatedat*No. 4 above) and relates to similar subject-matter.

6. United States Patent Specification No. US 5,252,555 Title: "Microemulsions containing a perfuming concentrate and corresponding product" The specification discloses a non-alcoholic perfuming product comprising a lipophilic phase based on a concentrate of odoriferous substance or perfume and a water-soluble phase, the phases being combined in a microemulsion and the content of concentrate of : * odoriferous substances being between approximately 5 and 50% by weight of the product, a surfactant based on polyethylene glycol, a first cosurfactant based on polyglycerol and a second co-surfactant based on ether phosphate also being combined in the microemulsion.

The product has application in the production of cosmetic products. I..

7. UK Patent Application No. GB 2400 555 : * : :* Title: "Emulsions having a fragrance or perfume in the oil phase, their preparation and *:. 20 products containing them" This patent specification discloses emulsions, especially water-in-silicone oil emulsions, containing fragrances or perfumes in the oil phase of the emulsion. The emulsions are made by (i) preparing an oil phase containing as ingredients a vinyl-type polymer having in its molecular chain a carbosiloxane dendnmer; a volatile linear silicone oil, a non-volatile linear silicone oil, a volatile cyclic silicone oil, or an organic oil; a surfactant; an oil soluble emollient; and a fragrance or perfume; and mixing the ingredients of the oil phase; (ii) preparing an aqueous phase containing as ingredients, water, a thickening agent, and a water soluble emollient, and mixing the ingredients of the aqueous phase; (iii) adding the aqueous phase to the oil phase; and (iv) mixing the two phases to form the emulsions in which the fragrance or perfume remains in the oil phase of the emulsion. The vinyl-type polymer is preferably obtained by potymerizing a vinyl monomer with a carbosiloxane dendrimer macromonomer. The emulsions can be used as components of various products, especially cosmetic products. The products have particular utility in treating hair, skin or underarm areas of the human anatomy.

8. International Patent Publication No. WO 00/59463 Title: "Liquid compositions comprising skin benefit agent" This patent specification discloses a stable aqueous liquid comprising a surfactant, a dispersed cationic polymer particle and a small particle benefit agent. The dispersed polymer interacts with the benefit agent, without need of an additional structurant to stabilize particles in solution. Further, upon dilution, enhanced cationic deposition is achieved.

9. International Patent Publication No. WO 03/01 5736 :..::: Title: "Perfume-containing composition" :. This patent specification discloses an aqueous skin-care, hair-care or fabric-care * .;: composition comprises surfactant, silicone insoluble in water, and perfume having a solubility parameter (SP) not exceeding about 20. By using a perfume with a low SP value, the disclosed invention enables good partitioning of perfume into the silicone of the :. 20 composition, which means that the perfume will be associated with the silicone and deposited therewith onto skin, hair or fabric in use.

The compositions disdosed in the prior art include water and in some instances also include ethanol or other alcohol.

Summary of the Invention

Certain products, sunscreening products especially, would benefit from anti-insect particularly mosquito-repellent properties. Of these, citronella has a history of gentle insect repellence, for example, in candles, etc. However, in anhydrous products, especially those containing high levels of silicone, citronella and other perfume oils are incompatible, resulting in a two-layer (two-phase) system.

Aqueous perfumes require the incorporation of relatively high levels of solubiliser which give problems with foam formation in production. The products may be viscous and usually imparts a tacky sensaticn on drying. For this reason, aqueous perfumes of extrait strength (>cal) 5% are very difficult to formulate. Silicone oils have a dry, elegant aspect which is neither oily nor tacky. They are available in a variety of volatilities and hence provide an elegant formulation vehicle for perfumes.

The present invention seeks to alleviate theproblems associated with formulating anhydrous products comprising relatively high levels of silicone compounds and perfume oils such as citronella, for instance.

Accordingly, the present invention provides a perfumed microemulsion composition :*. comprising at least one perfume oil incorporated into a silicone compound. S...

The microemulsion compositions of the present invention comprise: :. (i) at least one silicone compound; * .;: (ii) one or more perfume oils; and S (iii) one or more emulsifiers : .. substantially in the absence of alcohols such as ethanol wherein all three components are *5*S :. 20 present and where the proportion of emulsifier(s) relative to the other two components does not exceed 40% wlw.

Preferably, the proportion of emusifier(s) does not exceed 30% w/w.

The provision of perfumed compositions which are partially or totally alcohol-free has a number of advantages associated therewith, namely, the environmental requirements of low VOC emissions; the eschewal of alcohol as a delivery vehicle for cultural and religious reasons; the perception that in warm weather a fine, lightly-perfumed cooling aqueous mist is preferable to the more tradWonal alcoholic colognes.

The microemulsion compositions of the invention are stable and transparent.

The microemulsion compositions of the present invention have the advantages that they provide alcohol-free and anhydrous products in a stable microemulsion system.

Advantageously, the silicone compound may comprise a volatile silicone compound.

The silicone compounds included in the microemulsion compositions of the present invention, are preferably cyclic, and may have from 3 to 5 and/or from 7 to 10 silicon atoms, more preferably either 5 or 7 silicon atoms, most preferably 5 silicon atoms (cyclopentasiloxane). These preferred volatile cyclic silicone matenals conform to the following formula L[!Ji :..::: .1. S...

wherein n is from 3 to about 10, and n is 6 for cyclohexasiloxane and n is 5 for * 15 cyclopentasiloxane or n is 7 for cycloheptasiloxane and so forth. Optional volatile silicone materials for use herein include, but are not limited to, cyclopentasiloxane (commercially available from G.E. Silicones); Dow Coming 245, 246, 344 and 345 available from Dow Coming Corp.); GE 7207, GE 7158 and Silicone Fluid SF-1202 (available from General Electric Co.); ABIL B8839 (available from Goldschmidt); KF995 (available from Shin-Etsu) and combinations thereof.

Preferably, the at least one perfume oil included in the perfumed microemulsion composition of the invention may have insect-repellent properties.

Preferably, the perfume oil is selected from the group comprising citronella oil, lemon oil, eucalyptus oil, pine oil, cedar oil and lavender oil which have insect-repellent properties and particularly anti-mosquito properties. Accordingly, one use for the compositions of the present invention is as an insect repellent for instance, as a sunscreen which also has insect repellence. Other uses for the compositions include use as an alcohol-free cologne, a room deodorant or an air freshener.

Ideally, the microemulsion compositions also comprise an emulsifier and preferably a co-emulsifier.

The emulsifier and co-emulsifier preferably comprise a glyceryl ester and a polyglyceryl stearate, respectively. The glyceryl ester preferably comprises the partial glyceride of caprylic, capric and partially neutralized glyceryl laurate. This is available under the tradename, IMWITOR 380 supplied by Gattefosse. The polyglyceryl stearate preferably comprises polyglyceryl-4-isosterate. This is available under the tradename, ISOLAN Gl-34, also sold by T.H. Goldschmidt.

The microemulsion compositions of the present invention are prepared by following the :... shaded areas of the partial pseudo-ternary phase diagrams of Figures 1 -8, inclusive, using a silicone compound, perfume oil and emulsifier(s) as the three components of the system depicted in the partial pseudo-ternary phase diagrams.

* The present invention will now be described more particularly with reference to the : * accompanying drawings and the Examples provided hereinbelow. S...

20 The drawings show partial pseudo-ternary phase diagram representing the components of the microemulsions of the present invention. It should be noted that the partial pseudo-ternary phase diagrams accompanying this application are partial in the sense that only the upper portion of the conventionally represented equilateral triangle diagram is shown because this is the portion that is of interest in the present invention. In the accompanying partial pseudo-ternary phase diagrams, a mixture of any of the three component compositions of the invention can be represented by a point on the interior of the triangle.

Points along the actual sides themselves of the triangle, of course, only represent a binary mixture of the two components indicated at both ends of a particular side.

In the drawings: Figure 1 is a partial pseudo-ternary phase diagram of a silicone, namely, decamethylcyclopentasiloxane (available under the tradename, Volatile Silicone Fluid 345 sold by Dow Coming) and citronella oil, and an emulsifier and co-emulsifier sold under the tradenames, ISOLAN Gl-34 and IMWITOR 380 showing in the shaded area, the stable, transpar3nt mcroemusion completely in the absence of alcohols such as ethanol; Figure 2 is a partial pseudo-ternary phase diagram of perfume oil, namely, citronella oil, silicone (Volatile Silicone Fluid 345 sold by Dow Corning) and emulsifier and co-emulsifiers showing in the shaded area, the stable, transparent microemulsion substantially in the absence of alcohols such as ethanol; the emulsifiers comprise ISOLAN Gl-34 and IMWITOR 380.

Figure 3 is a partial pseudo-ternary phase diagram of perfume oil, silicone and emulsifier showing in the shaded area, the stable, transparent microemulsion substantially in the : absence of alcohols such as ethanol; the emulsifiers comprise ISOLAN Gl-34 and IMWITOR 380 and the silicone compound comprises decamethylcydopentasiloxane sold by Dow Coming under the tradename Volatile Silicone Fluid 345 and the perfume oil comprises citronella oil.

S S..

Figure 4 is a partial pseudo-ternary phase diagram of perfume oil, silicone and emulsifier showing in the shaded area, the stable, transparent microemulsion substantially in the * 20 absence of alkanols such as ethanol; the co-emulsifiers comprise 33.3% ISOLAN Gl-34 and 66.6% IMWITOR 380; the silicone compound comprises decamethylcyclopentasiloxane sold by Dow Coming under the tradename, Volatile Silicone Fluid 345 and the perfume oil comprises citronella oil.

Figure 5 is a partial pseudo-ternary phase diagram of perfume oil, silicone and emulsifier showing in the shaded area, the stable, transparent microemulsion substantially in the absence of alkanols such as ethanol; the co-emulsifiers comprise 33.3% ISOLAN Gl-34 and 66.6% IMWITOR 380; the silicone compound comprises decamethylcyclopentasiloxane sold by Dow Corning under the tradename, Volatile Silicone Fluid 345 and the perfume oil comprises lemon oil.

Figure 6 is a partial pseudo-ternary phase diagram of perfume oil, silicone and emulsifier showing in the shaded area, the stable, transparent microemulsion substantially in the absence of alkanols such as ethanol; the emulsifier comprises 33.3% ISOLAN Gl-34 and 66.6% IMWITOR 380 and the silicone comprises a mixture of cyclopentasiloxane and cyclohexasiloxane, (sold by Dow Corning under the tradename, silicone fluid UP-1004) and the perfume is perfume 1" (the formulation of perfume "1" is given in Example 2); Figure 7 is a partial pseudo-ternary phase diagram of perfume oil, silicone and emulsifier showing in the shaded area, the stable, transparent microemulsion substantially in the absence of alkanols such as ethanol; the co-emulsifiers comprise 33.3% ISOLAN Gl-34 and 66.6% IMWITOR 380; the silicone compound comprises decamethylcyclopentasiloxane sold by Dow Corning under the tradename, Volatile Silicone Fluid 345 and the perfume oil comprises lavender oil; and Figure 8 is a partial pseudo-ternary phase diagram of perfume oil, silicone and emulsifier showing in the shaded area, the stable, transparent microemulsion substantially in the absence of alkanols such as ethanol; the emulsifier comprises 33.3% ISOLAN Gl-34 and re.. 66.6% IMWITOR 380 and the silicone comprises a mixture of cyclopentasiloxane and cyclohexasiloxane, (sold by Dow Corning under the tradename, silicone fluid UP-1004) and the perfume is citronella oil. * ** * * **

: * 20 Procedure for producing the microemulsions of the invention The microemulsions of the present invention are prepared by combining the components in the proportions and amounts indicated by the shaded areas of the phase diagrams of Figures 1-8, inclusive using silicone compound, perfume oil and at least one emulsifier as the components.

The emulsifiers, ISOLAN Gl-34 and IMWITOR 380 are blended until homogeneous. The silicone is then added to the emulsifiers and mixed well until the mixture clarifies, before the perfume oil is added.

When a microemulsion is formed, the mixture becomes transparent to white light. For example, an acceptable insect repellent microemulsion is one that produces a clear solution in the finished product and which contains no alcohol content.

Refemng now to Figure 1 which is a partial pseudo-ternary phase diagram of the stable transparent microcmulsion of the present invention which comprises: (iv) at least one silicone compound; (v) one or more perfume oils; and (vi) one or more emulsifiers substantially in the absence of alcohols such as ethanol wherein all three components are present and where the proportion of emulsifier(s) does not exceed 40%.

Referring to Figure 1, the point indicated by reference numeral 1 indicates 100% of a silicone composition comprising 97.5% decamethylcyclopentasiloxane (Volatile Silicone Fluid 345) and 2.5% citronella oil. The point indicated by reference numeral 2 indicates approximately 40% ISOLAN Gl-34 and the point indicated by reference numeral 3 indicates approximately 40% IMWITOR 380. The shaded area in Figure 1 is indicated by reference **. 15 numeral 50. S...

The side of the diagram indicated by reference letter B shows increasing values from approximately 60% silicone compound/perfume oil composition up to 100% silicone compound/perfume oil composition and decreasing values of ISOLAN Gl-34 from 100% down to approximately 40% ISOLAN Gl-34. The side indicated by reference letter A shows :.:::. increasing amounts of emulsifier IMWITOR 380 from 0 to 100% starting from point 2 and ending at point 3. The side indicated by reference numeral C indicates increasing amounts of IMWiTOR 380 from 0% at point I to approximately 40% IMWITOR 380 at point 3.

It can be extrapolated from Figure 1 that a line drawn from the apex (point 1 on Figure 1) through point rn will intersect the base of the phase diagram along the side A Goining points 2 and 3) at the point indicating a binary composition comprising 66.6% IMWITOR 380 and 33.3% ISOLAN Gl-34. This particular relative proportion of IMWITOR 380 and ISOLAN GI- 34 was used in subsequent Examples and was found to be particularly effective in producing microemulsion compositions that were clear.

Referring now to Figure 2, the shaded area in Figure 2 is indicated by the reference numeral 51. Point 4 on Figure 2 represents 100% of a composition comprising 89% decamethylcyclopentasiloxane (Volatile Silicone Fluid 345) with 11% perfume oil, namely, citronella oil. Point 5 represents approximately 40% of polyglyceryl-4 Isostearate (ISOLAN Gl-34), andpoint 6 represents approximately 40% of IMWITOR 380.

Referring now to Figure 3, the point indicated by the reference numeral 7 shows 100% of a silicone composition consisting of 50% decamethylcyclopentasiloxane (Volatile Silicone Fluid 345) and 50% citronella oil. The point indicated by reference numeral 8 indicates approximately 60% ISOLAN Gl-34. The shaded area of the diagram indicated by reference numeral 52 shows the stable transparent microemulsion area.

In Figure 3, the side of the diagram indicated by reference letter G indicates a binary mixture of ISOLAN Gl-34 and IMWITOR 380 with increasing amounts of IMWITOR 380 moving from point 8 to point 9. Likewise, the side of the diagram indicated by reference letter H represents a binary mixture of ISOLAN Gl-34 and the silicone composition consisting of 50% Volatile Silicone Fluid 345 and 50% citronella oil with increasing amounts .,** 15 of the silicone compound moving from point 8 to apex point 9. The side of the diagram indicated by reference letter I represents the binary mixture comprising IMWITOR 380 and the silicone compound with increasing amounts of the silicone compound moving from point :.. 8 to apex point 9.

S *5S

S

Figure 4 is another partial pseudo-ternary phase diagram showing a stable transparent : * : ::* microemulsion composition consisting essentially of: * (i) silicone comprising decamethylcyclopentasiloxane; (ii) perfume oil comprising citronella oil; and (iii) an emulsifier and co-emulsifier comprising 66.6% IMWITOR 380 and 33.3% ISOLAN Gl-34, completely in the absence of any alcohol. The area which indudes the components of the present invention is indicated by reference numeral 53. The point indicating 100% silicone compound is indicated by reference numeral 10 and the point indicating approximately 40% oil is indicated by reference numeral 11. The point showing 40% co-emulsifiers (comprising 33.3% ISOLAN GI 34 and 66.6% IMWITOR 380) is indicated by reference numeral 12.

Referring to Figure 4, reference numeral 10 indicates 100% silicone, namely Decamethylcyclopentasiloxane (sold under the tradename Volatile Silicone Fluid 345); * 13 reference numeral 11 indicates 40% citronella oil and reference numeral 12 indicates 40% co-emulsifier comprising 33.3% ISOLAN GI-34 and 66.6% IMWITOR 380.

Referring now to Figure 5, reference numeral 13 indicates 100% silicone, namely, decamethylcyclopentasiloxane (Volatile Silicone Fluid 345); reference numeral 14 indicates 40% lemon cii and reference numeral 15 indicates 40% co-emulsifiers comprising 33.3% ISOLAN GI 34 and 66.6% IMWITOR 380. The shaded area is indicated by reference numeral 54.

Referring now to Figure 6, reference numeral 16 indicates 100% silicone, in this case, a mixture of decamethyicyclopentasiioxane and decamethyicyciohexasiloxane, (sold under the tradename, silicone fluid ultrapure (UP) UP-i 004); reference numeral 17 indicates 40% of "perfume 1", the formulation of which is given in Example 2 and 4, and reference numeral 18 indicates 40% co-emulsifiers (comprising 66.6% IMWITOR and 33.3% ISOLAN Gl-34). S. 5. 15 * SS*

The shaded area on Figure 6 is indicated by reference numeral 54. S...

:. Referring now to Figure 7, point 19 indicates 100% silicone compound, namely * .:. decamethyicyclopentasiloxane (Volatile Silicone Fluid 345); point 20 indicates a point along the side T which indicates a binary mixture comprising 40% lavender oil and 60% : * : * decamethylcyclopentasiloxane; reference point 21 indicates a point along the side U of the diagram, representing approximately 60% decamethylcyclopentasiloxane and approximately 40% of a co-emulsifier composition containing 66.6% IMWITOR 380 and 33.3% ISOLAN GI-34.

Referring now to Figure 8, reference point 22 indicates 100% of a silicone composition comprising decamethylcyciopentasiloxane and decamethylcyclohexasiloxane (sold as silicone UP-1004); reference point 23 indicates a point along side W representing a binary mixture of approximately 40% citronella oil and approximately 60% silicone UP-I 004.

Reference point 24 along side X represents a binary mixture comprising 40% co-emuisifiers comprising approximately 60% silicone UP-1004 and approximately 66.6% IMWITOR 380 and 33.3% ISOLAN Gl-34.

Examples

In the following Examples, Volatile Silicone Fluid 345 is indicated by its chemical name, decamethylcyclopentasiloxane; Volatile Silicone Fluid 344 is indicated by the chemical names of its constituents, namely, octamethylcyclotetrasiloxane and octamethylcyclopentasiloxane; and Silicone UP-i 004 is indicated by the chemical names of its constituents, namely, decamethylcyclopentasiloxane and decamethylcyclohexasiloxane.

In the Examples, glyceryl laurate and IMWITOR 380 are used interchangeably. In the Examples, ISOLAN is referred to only by its chemical name, Polyglyceryl-4 Isosterarate.

The invention will be further described with reference to the following non-limiting

Examples:

**... 15 . Example I (Insect repellent formula) w/w% Decamethylcyclopentasiloxane -(tradename Volatile 89.15 Silicone Fluid 345) Polyglyceryl-4-Isostearate -(tradename ISOLAN GI-1.21 34) Glyceryl Laurate, Glyceryl Cocate and Glyceryl Citrate 2.34 (tradename IMWITOR 380) Citronella oil 2.30 Lavender oil 2.50 Eucalyptus oil 2.50 It is possible to have other ingredients included in the formulation. The above percentage (wiw %) figures refer to proportions of the three main components of the microemulsion system of the invention.

The chemical names for ISOLAN Gl-34 and IMWITOR 380 are: Polyglyceryl-4-isostearate and the partial glyceride of caprylic, capric and partially neutralized glyceryl laurate respectively. The supplier of ISOLAN Gl-34 and IMWITOR 380 is T.H. Goldschmidt.

Procedure: The microemulsions of the present invention are prepared by combining the components in the proportions and amounts indicated by the shaded areas of the phase diagrams of Figures 1-8, inclusive using silicone compound, perfume oil and at least one emulsifier as the components. S. *. 15 * ... The emulsifiers, ISOLAN Gl-34 and iMWITOR 380 are blended until

homogeneous. The ** S silicone is then added to the emulsifiers and mixed well until the mixture clarifies, before the :... perfume oil is added.

S S..

When a microemulsion is formed, the mixture becomes transparent to white light. For example, an acceptable insect repellent microemulsion is one that produces a clear solution * in the finished product. The microemulsion compositions of the invention contain no alcohol content and are anhydrous.

ExamDle 2 Formula for erfume w/w% Octamethylcyclotetrasiloxane and Octamethylcyclopentasiloxane (Dow Coming Silicone 344 Fluid) 85.2 ISOLAN Gl-34 2.5 IMWITOR 380 4.9 Perfume 1 7.4 Perfume 1' Formula wIw% Diethyl phthalate 78.70 a-lonone 7.13 Phenyl ethyl alcohol 4.16 Linalool 2.85 Phenoxyethanol 2.76 Cineole 2.24 Camphor 0.88 Linalyl acetate 0.78 Limonene 0.22

:"... 15 Example 3

A simple UVB sunscreen with insect repellerlce *.

(Point (a) on Figure 1) w/w% Decamethylcyclopentasiloxane 82.9 : 20 2-ethylhexyl-4-methoxycinnamate 4.0 Glyceryl laurate 7.0 * : Polyglyceryl-4 Isostearate 7.0 Citronella Oil 2.0 The wlw% amount of decamethylcyclopentasiloxane in the composition is 82.9%. In ternary diagrams (including the pseudo-ternary diagrams accompanying this application), it is only the relative proportions of the principal ingredients that are indicated in the diagrams.

Thus, point (a) on Figure 1 indicates approximately 89% decamethylcyclopentasiloxane but if one eliminates the 2-ethylhexyl-4-methoxycinnamate and calculates the relative percentages of the three ingredients, the wlw% amounts are as indicated above.

Example 4 (An a'cohol-ree co!ogne) (Point (c) on Figure 6) w/w% Decamethylcyclopentasiloxane + decamethyl cyclohexasiloxane (sold under the tradename, Silicone UP-1004) 75.8 Glyceryl laurate 5.4 Polyglyceryl-4 Isostearate 10.8 Perfume 1' 8.0 wherein the formula for the perfume I' component is as follows: Perfume 1' Formula w/w% Diethyl phthalate 78.70 cz-lonone 7.13 * . :..::: Phenyl ethyl alcohol 4.46 **.

Linalool 2.85 :*. 20 Phenoxyethanol 2.76 * Cineole 2.24 **S Camphor 0.88 : *. Linalyl acetate 0.78 S...

*:. Limonene 0.22 Example 5 (A simple room deodorant) (similar formulation to but more complex than the oint (e) on Figure 7) wlw% Decamethylcyclopentasiloxane 79.2 Glyceryl laurate, Glyceryl Cocate, Glyceryl Citrate (IMWITOR 380) 3.0 Polyglyceryl-4 Isostearate 8.0 Lemon Oil 6.8 Lavender Oil 1.0 Cedar Oil 2.0 Exam le 6 (A lemon oil air freshener) (Doint (b) on Figure 5) Reading the coordinates of point (b) on Figure 5 shows that the composition corresponding to point (b) has the following composition: wlw% Decamethylcyclopentasiloxane 80.0 IMWITOR 380 4.7 Polyglyceryl-4 Isostearate 2.3 Lemon Oil 13.0 ExamDle 7 (An alcohol-free lavender sDray) (Point (d) on Figure 7) w/w% Decamethylcyclotetrasiloxane 81.0 : *** IMWITOR 380 6.0 S...

Folyglyceryl-4;sostearate 3.0 Lavender Oil 10.0 It is to be understood that the invention is not limited to the specific details described here which are given by way of example only and that various modification and alterations are possible without departing from the scope of the invention as defined in the appended . claims.

Claims

CLAIMS: * 1. A pcrfumed* croemusion ccmpostion comprising at least one

perfume oil incorporated into a silicone compound.
2. A perfumed microemulsion composition as claimed in claim 1 wherein the silicone compound comprises a volatile silicone compound.
3. A perfumed microemulsion composition as claimed in claim 1 or claim 2 wherein the silicone compounds included in the microemulsion composition are preferably cyclic, and may have from 3 to 5 and/or from 7 to 10 silicon atoms, more preferably either 5 or 7 silicon atoms, most preferably 5 silicon atoms (cyclopentasiloxane).
4. A perfumed microemulsion composition as claimed in claim 1 wherein the at least 15 one perfume oil is selected from the group comprising citronella oil, lemon oil, eucalyptus oil, pine oil, cedar oil and lavender oil.
5. A perfumed microemulsion composition as claimed in any one of the preceding claims wherein the compositions also comprise an emulsifier.
6. A perfumed microemulsion composition as claimed in claim 5 wherein a co- ** emulsifier is also included.
7. A perfumed microemulsion composition as claimed in claim I wherein the composition comprises the following three components: (i) at least one silicone compound; (ii) one or more perfume oils; and (iii) one or more emulsifiers substantially in the absence of alcohols such as ethanol wherein all three components are present and where the proportion of emulsifier(s), relative to said other two components, does not exceed 40% w/w.
8. A perfumed microemulsion composition as claimed in claim 7, wherein the relative proportion of emulsifier(s) does not exceed 30% w/w.
9. A perfumed microemulsion composition as claimed in claim 6 wherein the emulsifier and co-emulsifier comprise a glyceryl ester and a polyglyceryl stearate, respectively.
10. A perfumed microemulsion composition as claimed in any preceding claim wherein the composition is anhydrous.
11. A perfumed microemulsion composition as claimed in any preceding claim wherein the composition is free of alcohol.
12. A perfumed microemulsion composition as daimed in claim 9 wherein the glyceryl ester comprises the partial glyceride of caprylic, capnc and partially neutralized glyceryl 15 laurate.
13. A perfumed microemulsion composition as claimed in claim 9 wherein the polyglyceryl stearate comprises polyglyceryl-4-isosterate.

S *5*

S

* 20
14. A perfumed microemulsion composition as claimed in any preceding claim wherein :.:.. the silicone compound comprises decamethylcyclopentasiloxane. S.

S
15. A perfumed microemulsion composition as claimed in any one of claims 1 to 13 wherein the silicone compound comprises a mixture of octamethylcyclotetrasiloxane and octamethylcyclopentasiloxane.
16. A perfumed microemulsion composition as claimed in any one of claims 1 to 13 wherein the silicone compound comprises a mixture of decamethylcyclopentasiloxane and decamethylcyclohexasiloxane.
17. A perfumed microemulsion composition as claimed in any one of the preceding claims wherein the composition provides an insect-repellent composition.
18. A perfumed microemulsion composition as claimed in claim 17 wherein the composition provides a UV sunscreen with insect repellence.
19. A perfumed microemulsion composition as claimed in any one of claims 1 to 16 wherein the composition provides an alcohol-free cologne.
20. A perfumed microemulsion composition as daimed in any one of claims I to 16 wherein the composition provides a room deodorant.
21. A perfumed microemulsion composition as claimed in any one of claims I to 16 wherein the composition provides an air freshener.
22. A perfumed microemulsion composition as claimed in any one of claims I to 16 wherein the composition provides an alcohol-free perfumed spray. * S..

**e**
23. A perfumed microemulsion composition as claimed in any preceding claim wherein S...

silicone compound is induded in an amount of between 60% and 89% of the composition. * S * ...

*:.
24. A perfumed microemulsion composition as claimed in claim 18 wherein the silicone compound is decamethylcyclopentasiloxane and the composition provides a UV sunscreen : with insect repellence properties. *..

S
25. A perfumed microemulsion composition as claimed in any one of claims 6 to 24 wherein the emulsifier and co-emulsifier are included in relative proportions of 2:1.
26. A perfumed microemulsion composition as daimed in claim 24 wherein the emulsifier is included at 66.6% and the co-emulsifier is included at 33.3%, relative proportions to each other.
27. A perfumed microemulsion composition as claimed in any one of claims 6 to 26 wherein the emulsifier and co-emulsifier are included in an amount from 0.01% to approximately 40% of the total composition.
28. A perfumed microemulsion composition as claimed in any one of claims 6 to 26 wherein the emulsifier and co-emulsifier are included in an amount from 4% to opproximately 20% of the total composition.
29. A perfumed microemulsion composition substantially in accordance with any one of the embodiments herein described, in the Examples and/or with reference to and as shown in the accompanying drawings. a. a. a S... a * a a * a*a a a.$ a. a a S..

S a.. a