WO1996003963A1

WO1996003963A1 - Aqueous compositions

Info

Publication number: WO1996003963A1
Application number: PCT/US1995/008739
Authority: WO
Inventors: Sarah Katriona Marie Dobson; Charles Marie Alain Dureau
Original assignee: The Procter & Gamble Company
Priority date: 1994-07-30
Filing date: 1995-07-12
Publication date: 1996-02-15
Also published as: GB9415450D0; AU3096695A

Abstract

An aqueous, perfumed cosmetic composition which is essentially free of short-chain, monohydric alcohols and which comprises: a) a first nonionic surfactant having general formula (I) in which R1 is an alkyl group having from about 10 to about 22 carbon atoms and m and n represent weight-averages in the range from about 2 to about 80; and b) an auxiliary nonionic surfactant comprising one or more polyethoxylated nonionic surfactants of HLB from about 10 to about 16. The compositions of the invention have excellent clarity and stability and are particularly suitable for perfuming skin or hair where the use of short chain alcohols is preferably avoided.

Description

AQUEOUS COMPOSmONS

Field of the Invention

The present invention relates to aqueous compositions such as perfumed cosmetic compositions, coolant compositions and the like and more particularly, to compositions which are essentially free of short-chain alcohols and which are suitable for application to the skin or mucosa. The present invention also relates to a method for applying perfume to the skin using these compositions.

Background of the Invention

Traditionally, perfumes intended for application to the skin are dissolved in short chain alcohols, especially monohydric alcohols, or mixtures thereof with water. Ethanol is commonly used as such a solvent

Ethanol and other short chain monohydric alcohols have several disadvantages as perfume solvents. They are volatile organic compunds whose release into the environment is undesirable. Their f ammability presents a fire hazard both in production and in use at home. T ey are relatively expensive and, further, have their own odour, which may interfere with that of the perfume. Moreover, for products which are applied to the skin, the short-chain alcohols can cause undesirable, and sometimes painful, stinging. It would thus be desirable to avoid the use of these alcohols as perfume solvents. Similar considerations apply to low molecular weight polyhydric alcohols such as glycols. The preferred medium for the perfume is water, which is cheap, innocuous, non-flammable and odourless.

Generally, most perfumes are effectively immiscible with water, and it is therefore required to use a surfactant to form an emulsion or to otherwise solubilise the perfume. To be suitable for many applications where, traditionally, alcoholic perfume solutions have been used, the compositions should be physically stable and substantially clear. Preferably the mixtures will be microemulsions or solutions. For perfume compositions to be used as colognes, then the formulations will, ideally, be of low viscosity and will not leave a sticky feeling upon application to the skin. The surfactants used should not themselves have an odour which would substantially interfere with that of the perfume and they should be mild to the skin. It is also desirable that the perfume compositions should have a high degree of clarity. Similar considerations apply to aqueous compositions containing other oily materials, for example physiological coolants.

B. Angla, 'The Solubilisation in Water of Essential Oils and Other Odorants' • Soap, Perfumery and Cosmetics (1 66), pp 375 - 382 discusses the micellar solubilisation in water of, especially, perfume oils and uses the concept of HLB (hydrophile - lipophile balance) number for the characterisation of surfactants. It is taught therein that although, often, solubilisers of different HLB's will be required, knowledge of HLB in itself is insufficient and the nature.of the surfactant also plays a role. Suitable surfactants given as examples are generally alcohol ethoxylates such as ethoxylated castor oil and cetyl alcohol ethoxylate. The HLB concept is also described more fully in The HLB System', published by ICI Americas Inc, Wilmington, Delaware.

EP-A-261.351 describes the solubilisation of perfume oils in water or water-ethanol mixtures using a mixture of a Cj-C6 alkanol propylene oxide / ethylene oxide oligomer with a nonionic emulsifier. The nonionic emulsifier is preferably an ethoxylated or propoxylated/ethoxylated alcohol or ester of which many examples are given. Preferably, 0.5 to 1.0 parts of the surfactant mixture are used to solubilise 1 part of the perfume. The main advantage of the invention is stated to be the low amount of solubiliser that may be used.

EP-A-571,677 discloses clear oil-in- water microemulsions comprising one or more primary surfactants with HLB between 9 and 18, where the weight ratio of perfume oil to surfactant is from 0.8S to 2.5. A variety of suitable surfactants is listed, the surfactant mixture being chosen to suit the perfume. 'Clear* is defined as transparent or translucent when observed through a layer of not more than 10cm thickness.

It has now been found that, whilst the disclosures of the art go some way in teaching how to make clear perfumed aqueous compositions, none of them is entirely satisfactory. In particular, it is difficult to achieve superbly clear, perfumed, aqueous compositions, having low viscosity with a good odour.

It is accordingly an object of this invention to provide clear, aqueous, perfumed compositions that are essentially free of short chain monohydric alcohols.

It is a further object of the invention to provide perfumed, aqueous compositions that have low viscosity, do not leave a sticky feeling upon application to the skin and which preserve the original character of the perfume. It is yet a further object of the invention to provide clear, aqueous compositions that are essentially free of short chain monohydric alcohols and which comprise oily materials other than perfumes e.g. physiological coolants.

Summary of the Invention

According to one aspect of the present invention there is provided an aqueous, perfumed cosmetic composition which is essentially free of short-chain, monohydric alcohols and which comprises:

a) a first nonionic surfactant having the general formula

in which R] is an alkyl group having from about 10 to about 22 carbon atoms and m and n represent weight-averages in the range from about 2 to about 80; and

b) an auxiliary nonionic surfactant comprising one or more polyethoxylated nonionic surfactants of HLB from about 10 to about 16.

The compositions of the invention have a viscosity preferably less than about 6 mPa.s, more preferably less than 4 mPa.s, the viscosity being measured at 20°C with a Brookfield LVT viscometer using a UL adapter. In terms of clarity, the compositions of the invention preferably have a clarity index of less than about 50 nephetometric turbidity units (NTU), preferably less than about 40 NTU, even more preferably less than about about 30 NTU, clarity being measured at 20°C using an Orbico-Hellige Series 965 Turbidity Meter calibrated over the range 0 to 99.9 NTU.

All levels and ratios are by weight of total composition, unless otherwise indicated.

Detailed Description of the invention

The compositions of the invention include as an essential feature an oily material such as perfume, coolant etc.. As used herein the term 'perfume' includes materials which are used primarily to impart a desirable odour to the composition. These materials, generally of an oily or lipophilic nature, may be natural products such as essential oils, absolutes, resins, etc., or synthetic perfume components such as hydrocarbons, alcohols, aldehydes, ketones. ethers, acids, esters, acetals, ketais, nitriles etc., including saturated and unsaturated compounds, aliphatic, carboxylic and heterocyclic compounds. Examples of such perfume components are: geranyl acetate, linalyl acetate, citronellyl acetate, dihydromyrcenyl acetate, terpinyl acetate, tricyclodecenyl acetate, tricyclodecenyl propionate, 2-phenylethyl acetate, benzyl acetate, benzyl salicylate, benzyl benzoate, styrallyl acetate, amyl salicylate, methyl dihydrojasmonate, phenoxyethyl isobutyrate, neryl acetate, trichloromethyl- phenylcarbinyl acetate, p-tertiary butyl-cyclohexyl acetate, isononyl acetate, cedryl acetate, vetiveryl acetate, benzyl alcohol, 2-phenylethanol, linalool, tetrahydrolinalool, citronellol, dimethylbenzylcarbinol, dihydromyrcenol, tetrahydromyrcenol, terpineol, eugenol, geraniol, vetiverol, 3-isocamphyl-cyclohexanol, 2-methyl-3-(p-tertiary butylphenyl)- propanol, 2-methyl-3-(p-isopropylphenyl)-propanol, 3-(p-tertiary butylphenyl)-propanol, nerol, alpha-n-amylcmnamic aldehyde, alpha-hexyl-cinnamic aldehyde, 4-(4-hydroxy-4- methylpentyl)-3-cyclohexenecarbaldehyde, 4-(4-methyl-3-pentenyl)-3- cyclohexenecarbaldehyde, 4-acetoxy-3-pentyl-tetrahydropvran, 2-n-heptyl-cyclopentanone, 3-methyl-2-pentyl-cyclopentanone, n-decanal, n-dodecanal, hydroxycitronellal, phenylacetaldehyde dimethyl acetal, phenylacetaldehyde diethyl acetal, geranonitrile, citronellonitrile, cedryl methyl ether, isolongifolanone, aubepine nitrile, aubepine, heliotropine, coumarin, vanillin, diphenyl oxide, ionones, methyl ionones, isomethyl ionones, irones, cis-3-hexenol and esters thereof, indane musks, tetralin musks, isochroman musks, macrocyclic ketones, macrolactone musks, ethylene brassylate, aromatic nitromusks. The perfume may further include suitable extenders and diluents, for example: diethyl phthalate, triethyl citrate, etc. but only limited quantities of alcoholic or other water-miscible solvents such as ethanol, isopropanol or dipropylene glycol will be present in the perfume i.e. 25% by weight of the perfume or less. In general, perfumed compositions will have a total perfume content of from about 0.1% to about 20%, preferably from about 0.3% to about 15%, more especially from about 0.5% to about 10%. Moreover, the compositions will be essentially free, i.e. contain less than about 2%, preferably less than about 0.5%, of short chain (C1-C4) monohydric alcohols.

Additionally, the composition may comprise similarly oily or lipophilic materials used primarily for purposes other than purely olfactory ones, such as colourants, preservatives, physiological coolants, viscosity modifiers, etc. Where these additional lipophilic materials are used in combination with perfume, they generally will not comprise more than 50% by weight of the perfume. It is a feature of the invention, however, that non- perfume lipophilic materials such as physiological coolantsand the like can be incorporated in aqueous alcohol-free compositions with improved clarity and stability. Thus according to a further aspect of the invention, there is provided an aqueous coolant composition which is essentially free of short-chain, monohydric alcohols and which comprises:

a) a first nonionic surfactant having the general formula

R! -(OCHCH₂)— (OCH₂CH₂) OH

<_Ή₃ in which Rj is an alkyl group having from about 10 to about 22 carbon atoms and m and n represent weight-averages in the range from about 2 to about 80; and

Physiological cooling agent suitable for use herein include carboxamides, menthane esters and menthane ethers, and mixtures thereof.

Suitable menthane ethers for use herein are selected from those with the formula:

where R5 is an optionally hydroxy substituted aliphatic radical containing up to 25 carbon atoms, preferably up to 5 carbon atoms, and where X is hydrogen or hydroxy, such as those commercially available under the trade name Takasago, from Takasago International Corporation. A particularly preferred cooling agent for use in the compositions of the present invention is Takasago 10 [3-1-menthoxy propan-l,2-diol (MPD)]. MPD is a monog.ycerin derivative of 1-menthol and has excellent cooling activity.

The carboxamides found most useful are those described in US-A-4,136,163, January 23, 1979 to Wason et al., and US-A-4,230, 688, October 28, 1980 to Rawsell et al. The carboxamides in US-A-4,136,163 are N-substi ted-p-menthane-3-carboxamides. These compounds are 3-substituted-p-menthanes of the formula:

where R', when taken separately, is hydrogen or an aliphatic radical containing up to 25 carbon atoms; R" when taken separately is hydroxy, or an aliphatic radical containing up to 25 carbon atoms, with the proviso that when R' is hydrogen R" may also be an aryl radical of up to 10 carbon atoms and selected from the group consisting of substituted phenyl, phenalkyl or substituted phenalkyl, naphthyl and substituted naphthyl, pyridyl; and R' and R", when taken together with the nitrogen atom to which they are attached, represent a cyclic or heterocyclic group of up to 25 carbon atoms, e.g. piperidino, morpholino etc.

In the above definitions "aliphatic" is intended to include any straight-chained, branched- chained or cyclic radical free or aromatic unsaturation, and thus embraces alkyl, cycloalkyl, alkenyl, cyclo-alkenyl, alkynyl, hydroxyalkyl, acyloxyalkyl, alkoxy, alkoxyalkyl, aminoalkyl, acylaminoalkyl, carboxyalkyl and similar combinations.

Typical values for R' and R" when aliphatic are methyl, ethyl, propyl. butyl, isobutyl. n- decyl, cyclopropyl, cyclohexyl, cyclopentyl, cycloheptylmethyl, 2-hydroxyethyl, 3- hydroxy-n-propyl, 6-hydroxy-n-hexyl, 2-aminoethyl, 2-acetoxyethyl, 2-ethylcarboxyethyl, 4-hydroxybut-2-ynyl, carboxymethyl etc.

When R" is aryl typical values are benzyl, naphthyl, 4-methoxyphenyl, 4-hydroxyphenyl, 4-methylphenyl, 3-hydroxy-4-methylphenyl, 4-flurophenyl, 4-nitrophenyl, 2- hydroxynaphthyl, pyridyl. etc.

The carboxamides of US-A-4.230,688 are certain acyclic tertiary and secondary carboxamides. These have the structure

Rj — C* CONR'R" where R' and R". when taken separately, are each hydrogen, C1-C5 alkyl or Cj-Cg hydroxyalkyl and provide a total of no more than 8 carbon atoms, with the proviso that when R' is hydrogen R" may also be alkylcarboxyalkyl of up to 6 carbon atoms; R' and R", when taken together, represent an alkylene group of up to 6 carbon atoms, the opposite ends of which group are attached to the amide nitrogen atom thereby to form a nitrogen heterocycle, the carbon chain of which may optionally be interrupted by oxygen; Rj is hydrogen or C1-C5 alkyl; and R2 and R3 are each C1-C5 alkyl; with the provisos that (i) Rj, R2 and R3 together provide a total of at least 5 carbon atoms, preferably from 5-10 carbon atoms; and (ii) when K\ is hydrogen, R2 is C2-C5 alkyl and R3 is C3-C5 alkyl and at least one of R2 and R3 is branched , preferably in an alpha or beta position relative to the carbon atom marked (*) in the formula.

Suitable menthane esters for use herein are selected from those with the formula:

where R4 is hydrogen, hydroxy or an aliphatic radical containing up to 25 carbon atoms.

The physiological cooling agent is preferably present in an amount of from about 0.01% to about 1%, more preferably from about 0.02% to about 0.5%, most preferably from about 0.05% to about 0.3% by weight of composition.

An essential component of the composition of the invention is a first nonionic surfactant having the general formula:

R!

in which Rj is an alkyl group having 10 to 22 carbon atoms and m and n represent weight- averages in the range 2 - 80. Shorter chain length alkyl groups are avoided for efficacy reasons and because unreacted fatty alcohol in such surfactants is a source of malodour and occasionally of skin irritation. It will be understood that surfactants of this type are usually mixtures of varying degrees of ethoxylation / propoxylation, accordingly m and n represent the respective weight-averages of the number of propoxylate and ethoxylate groups. Both m and n are in the range from about 2 to about 80, however preferred values of m are from about 2 to about 20, more preferably from about 3 to about 10 and preferred values of n are from about 2 to about 60, more preferably from about 5 to about 50. One such material is PPG-5-ceteth-20 (available from Croda Inc as Procetyl A WS), where m and n have the values 5 and 20 respectively. In general, the ratio of this first surfactant to the perfume, coolant or other oily material will be in the range of from about 5:1 to about 1:3, preferably from about 3 : 1 to about 1 :2, more preferably from about 2: 1 to about 1:1.

The compositions of the invention further comprise an auxiliary nonionic surfactant. The auxiliary nonionic surfactant is preferably selected from polyethoxylated nonionic surfactants of HLB from about 10 to about 16. Preferably the HLB of such surfactants is from about 1 1 to about 15, more preferably from about 10 to about 14. The quantity of auxiliary surfactant is generally kept as low as possible, sufficient to provide the requisite clarity and stability. The quantity necessary to obtain a clear and stable composition obviously depends on the quantity of perfume or other oil. The minimum required ratio of total surfactant to oil in the composition (surfactant/oil ratio) tends to increase with decreasing oil content in the composition, so that in general, low oil contents require proportionately more surfactant than high oil contents. However, generally useful surfactant/oil ratios in the composition of the invention will be in the range from about 1 : 1 to about 4: 1 , preferably the ratio is from about 1.1 : 1 to about 3.5: 1 , most preferably from about 1.2: 1 to about 3:1. The ratio of first nonionic surfactant to auxiliary nonionic surfactant on the other hand is preferably from about 3:1 to 1:3, more preferably from about 2: 1 to about 1 :2.

Suitable nonionic auxiliary surfactants are e.g.: ethoxylated alkylphenol ethers, particularly octyl- and nonylphenol ethers containing 8-16 EO; ethoxylated aliphatic C6-C20 alcohols, which may be linear or branched and contain 8-16, preferably 9-15 EO;

Preferred auxiliary nonionic surfactants have an HLB of from about 10 to about 16, have minimal odour and have an alkyl chain length of 6-20 C-atoms, particularly of 8-14 C- atoms, such as; ethoxylated alkylphenol ethers, ethoxylated linear and branched Cg-C20 fatty alcohols, and ethoxylated hydrogenated castor oils. The nonionic surfactant mixture should be carefully selected so as to have an HLB which particularly suits the oil which is to be solubilised or emulsified. This may be done by testing the oil in the desired concentration with a standard range of surfactant solutions with stepwise increasing HLB and selecting the HLB value giving the clearest composition and/or the greatest range of temperature stability.

Additionally, the compositions of the invention may further comprise co-surfactants which improve the solubilizing properties of the first and auxiliary nonionic surfactants. These co-surfactants may be of the ionic (cationic, anionic, amphoteric) or nonionics other than those mentioned above. Suitable anionic co-surfactants include the sodium, potassium, ammonium or alkylammonium salts of alcohol sulphates, alcohol ether sulphates, sulphosuccinates and isethionates. Cationic co-surfactants suitable for use herein comprise quaternary ammonium compounds and amine oxides e.g. lauryldimethylamine oxide. Particularly suitable amphoteric co-surfactants are betaines such as cocoamidopropyl betaine.

The compositions of the invention may be prepared according to methods known in the art A suitable method consists of adding the surfactant mixture to the oil phase at such a temperature that a homogeneous mixture is obtained, followed by gradually adding the aqueous phase to this mixture while stirring until the water-in-oil emulsion reverses to an oil-in-water emulsion. Thereafter the remainder of the aqueous phase may be added more quickly. The temperature should not be higher than necessary to obtain a homogeneous surfactant / oil mixture in order to prevent loss or deterioration of the perfume, coolant etc. Suitably, the mixing may be done at room temperature.

The compositions according to the invention are suitable for a wide variety of applications and particularly for those applications where the use of organic solvents should be kept to a minimum. Examples are: use in aerosols or pump sprays for various purposes where a fire hazard may be involved, e.g. room deodorants; preparations for skin and hair, including in particular preparations for fine perfumery i.e. preparations primarily or exclusively intended for imparting an agreeable odour to the skin, cooling compositions for application to the skin or oral mucosa etc.

The following examples are illustrative of the clear perfumed aqueous compositions according to the invention. However, the invention is not limited thereto. Fxamples I - IV I II III IV

% % % %

PPG-5-ceteth-20 3.0 3.0 4.5 3.0

PEG-40 hydrogenated castor oil - 1.8 4.5 3.0

Trideceth-12 2.0 - - -

Trideceth-9 - 2.0 - 3.0

Perfume A^"'^' 1.5 2.0 6.0 6.0

Trimethyl butanamide 0.3 0.1 - -

Germall l l5 0.2 0.2 0.2 0.2

Water <_—-.. to 100%

^"*^" Perfume A is a complex mixture of ingredients used primarily for olfactory purposes.

Claims

1. An aqueous, perfumed cosmetic composition which is essentially free of short-chain, monohydric alcohol and which comprises:

a) a first nonionic surfactant having the general formula

in which Rj is an alkyl group having from about 10 to about 22 carbon atoms and m and n represent weight-averages in the range from about 2 to about 80; and

2. A composition according to Claim 1 wherein the aqueous composition has a total perfume content of from 0.1% to 20%, preferably from 0.3% to 15%, more especially from 0.5% to 10%.

3. A composition according to Claim 1 or Claim 2 wherein the weight ratio of the first nonionic surfactant to the perfume is from about 5:1 to about 1 :3, preferably from about 3: 1 to about 1 :2, more preferably from about 2: 1 to about 1:1.

4. A composition according to any of the preceding claims wherein the weight ratio of total surfactant to the perfume is from about 1 : 1 to about 4:1, preferably from about 1.1:1 to about 3.5:1, most preferably from about 1.2:1 to about 3:1.

5. A composition according to any of the preceding claims wherein the weight ratio of first nonionic surfactant to auxiliary nonionic surfactant is from about 3:1 to 1:3, preferably from about 2: 1 to about 1:2.

6. A composition according to any of the preceding claims wherein m averages from about 2 to about 20, preferably from about 3 to about 10, and n averages from about 2 to about 60, preferably from about 5 to about 50.

7. A composition according to any of the preceding claims wherein the auxiliary nonionic surfactant has an HLB in the range from about 1 1 to about 15, more preferably from about 10 to about 14.

8. A composition according to any of the preceding claims wherein the auxiliary nonionic surfactant is a Cg-C20 alcohol ethoxylated with from about 8 to about 16, preferably from about 9 to about 15 moles of ethylene oxide per mole of alcohol.

9. A process for perfuming skin or hair wherein a composition according to any of the preceding claims is applied to the skin or hair.