EP1032357A1 - Use of fluorinated solvents for the formulation of hair lotions - Google Patents

Abstract

The invention concerns a hair lotion characterised in that it contains a solvent¿n consisting of at least a hydrofluoroether of general formula (I) C¿n?HmF2n+1-m-O-CpHqF2p+1-q in which n = 1 to 20; m = 0 to 2n+1; p = 1 to 20; q = 0 to 2p+1.

Description

 Use of fluorinated solvents for the formulation of hair care lotions.

The invention relates to the field of the cosmetic and pharmaceutical industry. More specifically, the invention relates to hair care lotions for cosmetic or pharmaceutical use.

Hair care lotions are generally used to tone the hair, remove dandruff and other impurities from the scalp, and remove excess sebum secreted by the scalp. Certain hair lotions can also be used for therapeutic purposes. These lotions are generally for specific actions.

Their formula generally includes:

- A vehicle, which most often consists of ethanol titrating 30 to 50 °, chosen for its antiseptic properties and its ability to evaporate quickly; - emollients, such as, for example, castor oil and its derivatives, which compensate for the drying action of ethanol;

- sheathing polymers facilitating styling;

- antiseborrhoeic, anti-dandruff or superfatting, or even pharmaceutical active substances. Hair loss lotions can also contain:

- vasodilator compounds, such as, for example, extracts of capsicum, cinchona or nicotinic esters;

- biological extracts such as, for example, placental derivatives, amniotic fluid, mucopolysaccharides;

- panthenol or ethers derived (pantothenyl-ethyl-ether) which would be factors of growth of the hair;

- amino acids,

- vitamin complexes. Fragrance substances, such as camphor or oils essential, dyes as well as stabilizers (antioxidants, pH correctors) can complete the basic composition of such lotions for hair use.

These lotions are generally presented in the form of a monophasic or biphasic liquid system. In the case of monophasic systems, the various constituents of the lotion are dissolved or dispersed in water or in a hydroalcoholic mixture. In the case of two-phase liquid lotions, it is added to the formulation of deodorized light petroleum. This feature makes it possible to add to the lotion various lipophilic constituents which are poorly soluble in the hydroalcoholic phase. The immiscibility of light oil and water or hydroalcoholic solutions leads to the formation of the two liquid phases.

Ethanol, which, as already mentioned above, is very generally used as a vehicle in hair lotions, involves a certain number of drawbacks.

Thus, present in high concentrations (30 to 50%), it has a drying action on the scalp which can cause skin irritation. This aggressive effect must be neutralized by adding an emolient to the formulation.

The daily use of hair lotions containing alcohol leads to percutaneous absorption of this skin in sometimes large quantities. For obvious health reasons, this absorption of alcohol should be avoided. In addition, certain religions condemn the absorption of alcohol, whether by oral consumption or percutaneous absorption and therefore prohibit their practitioners from using perfumes and cosmetic products containing ethanol.

It will also be noted that the amounts of alcohol and of petroleum in the hair lotions are large enough to cause acute intoxication during accidental ingestion, in particular by young children, of such lotions.

Light oils, also frequently used in hair lotion formulations, also have recognized toxicity. By frequent or prolonged contact with the skin, light oils destroy the lipo-acid skin coating and can cause dermatoses of varying severity, with risk of secondary allergy. The vapors are irritating to the mucous membranes. At high concentration, they exert a narcotic action on the central nervous system (headache, dizziness, drowsiness). Certain light oils, officially called petrol A, petrol B and petrol C, have vapors rich in hexane and have been at the origin of serious polyneurites, notably in Japan and in certain European countries including France. Accidental ingestion of these essences is likely to cause serious hepato-digestive damage and sometimes nervous disorders (coma, respiratory incidents, etc.) with a serious prognosis. Furthermore, the possible presence of benzene in these solvents may have hematological implications.

The objective of the present invention is to provide hair lotions which do not contain ethanol.

Another object of the present invention is to allow the manufacture of such lotions which also do not contain light petroleum.

These objectives are achieved thanks to the invention which relates to a hair care lotion characterized in that it contains a solvent consisting of at least one fully or partially fluorinated hydrocarbon.

Preferably, said fluorinated solvent is chosen from the group consisting of: - linear saturated C _j , C _2Q totally or partially fluorinated hydrocarbons;

the hydrofluoroethers of general formula (I): C _n H _m F _{2n + 1-m} -OC _p H _q F _{2p + 1-q} in which n = 1 to 20; m = 0 to 2n + 1; p = 1 to 20; q = 0 to 2p + 1;

- the fluorinated derivatives of morpholine of general formula (II):

OC ₄ H _n F ₉ . _n N in which n = 0 to 8; - the fluorinated derivatives of N-alkylmorpholines of general formula (HI):

OC ₄ H _n F _8n NC _m H _p F _{2m + 1-p} in which n = 0 to 7; m = 1 to 20; p = 0 to 40;

- the fluorinated trialkylamines of general formula (IV):

(CnH _m F _{2n + 1-m} ) (C _p H _q F _{2p + 1-q} ) (C _x H _y F _{2x + 1-y} ) N in which n = 1 to 20; m = 0 to 40; p = 1 to 20; q = 0 to 40, x = 1 to 20; y = 0 to 40)

- fluorinated furan derivatives of general formula (V):

^C ₄ H _n F ₈ . _n O in which n = 0 to 7;

- the fluorinated derivatives of alkylfurans of general formula (VI):

CnH _m F _{2n +!} . _m -C ₄ H _p F ₇ . _p where n = 20; m = 0 to 40; p = 0 to 7.

Such fluorinated solvents have decisive advantages over conventional organic solvents, such as ethanol, which form part of the formulation of prior art hair lotions.

First, they are non-toxic. Various toxicological studies, in particular concerning perfluorinated alkanes and perfluorinated N-methylmorpholine, have been carried out on rodents. These studies have led to demonstrate oral atoxicity even for doses as high as 10 g / kg, in punctual administration, or 2 g / kg / day for 4 weeks. The

Perfluorinated N-methylmorpholine produces, at doses of 0.1 ml, a slight reversible irritation of the ocular connective tissues but without corneal alteration.

On the other hand, under the same conditions, fluorinated alkanes do not produce eye irritation. Furthermore, no skin irritation is observed for local applications of 0.5 ml of fluorinated solvent.

There is therefore, at present, no toxicological contraindication for the fluorinated solvents proposed by the invention for use in the context of hair care lotions. The fluorinated compounds proposed by the invention are also completely odorless or not very odorous. They can therefore be incorporated into hair lotion formulations without the risk of masking any perfumes.

Furthermore, it will also be noted that these fluorinated solvents are lipophilic compounds. They therefore make it possible, on the one hand, to dissolve the lipophilic constituents of the formulations and, on the other hand, to contribute to elimination of sebum.

These fluorinated solvents also have the advantage of being chemically inert and of not being able to react with any of the usual constituents of cosmetic formulations. These are volatile compounds which, after evaporation, leave no trace.

Finally, they do not pose a risk to the ecosystem.

According to a preferred variant, said solvent is chosen from the group consisting of methylperfluorobutylether, perfluorinated octane and perfluorinated nonane. It will be understood that the hair lotions according to the invention may include a fluorinated compound as described above or a mixture of such fluorinated compounds.

The invention will be more easily understood thanks to the description which follows of non-limiting embodiments thereof. Example 1

The light deodorized petroleum of a commercial hair lotion is replaced by a mixture of 50% (v / v) of methylperfluorobutylether (CH ₃ -O-

C ₄ F ₉ with n = l, m = 3, p = 4 and q = 0), 25% (v / v) of perfluorinated octane and 25% (v / v) of perfluorinated nonane. Methylperfluorobutylether makes it easy to dissolve fragrance substances. Perfluorinated octane and nonane are used because of their lower volatility than that of methylperfluorobutylether. They avoid too rapid evaporation of the organic phase during the application of the lotion and make it possible to prolong the feeling of freshness following the evaporation. Example 2

To eight volumes of an aqueous solution containing water-soluble active ingredients necessary for hair care, is added one volume of a mixture of 50% (v / v) of ethylperfluorobutylether (C ₂ H ₅ -OC ₄ F ₉ with n = 2, m = 5, p = 4 and q = 0) and 50% (v / v) of perfluorooctane. To this mixture is added 0.1% (v / v) of a mixture of essential oils of cypress, tea tree, chamomile and lavender, intended to perfume the composition and to provide additional hair care. Example 3

To eight volumes of an aqueous solution containing water-soluble active ingredients necessary for hair care, is added one volume of a mixture of 50% (v / v) of propylperfluorobutylether (C ₃ H ₇ -OC ₄ F ₉ with n = 3 , m = 7, p = 4 and q = 0) and 50% (v / v) of perfluorooctane. To this mixture is added 0.1% (v / v) of a mixture of essential oils of cypress, tea tree, chamomile and lavender, intended to perfume the composition and to provide additional hair care .

Claims

1. Hair care lotion characterized in that it contains a solvent consisting of at least one hydrofluoroether of general formula (I):

C _n H _m F2n + 1. _m -O-CpH _q F _{2p +} 1. _q in which n = 1 to 20; m = 0 to 2n + 1; p = 1 to 20; q = 0 to 2p + l.

2. Lotion according to claim 1 characterized in that said solvent contains methylperfluorobutylether.

3. Lotion according to claim 1 characterized in that said solvent contains ethylperfluorobutylether. If-. Lotion according to claim 1 characterized in that said solvent contains propylperfluorobutylether.