WO2008060130A2 - Detergent compositions in the form of microemulsions and use thereof in the treatment of alopecia - Google Patents

Abstract

The invention relates to detergent compositions in the form of stable, transparent oil-in-water-type microemulsions which are prepared in accordance with the invention and which take the form of a liquid or gel. The aforementioned compositions comprise water, electrolytes, fatty acids, a combination of fatty acid salt type surface-active agents and at least one nonionic surface-active agent, an oil preferably selected from oils containing long-chain triglycerides and, if desired, other auxiliary agents, additives and active principles. Said compositions can be used, in particular, to clean and condition keratinous matter such as hair or skin. The inventive compositions can micro-emulsify sebum on contact. The invention also relates to a cosmetic method for the treatment of androgenic alopecia or the prevention of hair loss.

Description

 "Detergent compositions in the form of microemulsions and their use in the treatment of alopecia"

The present invention relates to stable detergent compositions in the form of oil-in-water microemulsions that provide excellent washing properties.

In particular, the present invention relates to cosmetic compositions intended simultaneously for the cleaning and conditioning of keratin materials such as the hair and the skin.

More particularly, the present invention relates to cosmetic compositions in microemulsion form comprising vegetable oils and fatty acids for the treatment of alopecia.

Although the present invention relates primarily to body care and alopecia treatment compositions, it may also be of interest for other cleaning compositions, including dishwashing compositions, laundry compositions and hard surface cleaning compositions.

All publications, patent applications and granted patents mentioned in the present invention are incorporated therein in their entirety by reference.

Shiite hair, also called androgenic alopecia or baldness, is a common problem in our society, which affects many men and women. In a society where beauty and youth are considered to be the most beautiful of virtues, it is not surprising that hair loss is often perceived as an embarrassing factor and often hinders self-confidence and, consequently, also, the quality of life.

Alopecia is found in both men and women and usually begins after puberty. The hair follicles of the hair become very small, dramatically reducing the growth. It seems like heredity plays an important role. In general, it starts at the vertex and temples before reaching the top of the head. On the other hand, the crown remains hairy. Approximately one third of men between the ages of 25 and 40 suffer from androgenic alopecia. According to the Norwood-Hamilton classification, it is possible to determine the degree of baldness.

Testosterone is the most active male hormone. Testosterone is converted to dihydrotestosterone (DHT) in the presence of the enzyme 5-alphareductase. When the concentration of DHT is very high because of the very high presence of the enzyme 5-alphareductase, the hair cycle is altered. The growth phase (anagen) is shortened and the rest phase (telogen) is extended. Androgenic alopecia is characterized by progressive miniaturization of the hair.

5-alipeductase is a microsomal enzyme that exists as two isoenzymes synthesized from two different genes. In the scalp, we find the type 1 isoenzyme of 5α-reductase in the sebaceous glands, as well as in the hair follicle. In the skin, the activity of 5α-reductase is more important in the sebaceous gland than in other structures.

The high rate of DHT does not only modify the hair cycle, but it also increases the production of lipid secretions. The hair quickly takes on an oily appearance that requires more frequent washing. Excess sebum engulfs the skin and hair follicle, and causes secondary problems: irritation, itching, dandruff and hair loss.

Excess sebum is usually an aggravating factor but not enough. Some bald people do not develop seborrhea, and some oily hair does not fall. 00011

Currently, there is no definitive treatment for alopecia. Treatments exist for mild cases, they are not very effective on severe cases. The finasteride and minoxidil treatments are the most common, and have only a very moderate efficacy especially for extensive alopecia

The minoxidil 2% or 5% is used at a rate of 1 ml twice a day, in local application on dry scalp. Minoxidil can not be used by people who are allergic to propylene glycol or alcohol. In addition, minoxidil is not suitable for the treatment of patients with complete baldness. The most common side effects are skin reactions, such as local irritation and redness, dry skin with peeling or eczema. It is thus that after its interruption, a more important fall of the hair can appear.

Inhibition of 5-alphareductase is a new therapeutic approach. Finasteride is a 5-alphareductase inhibitor that works by reducing the level of DHT in the plasma and in the scalp. Other 5-alpha-aldehydease inhibitors include fatty acids, fiavanoids, catechols, which are described, for example, in US Patent Nos. 6576660 and 6696484 to Liao et al.

Certain unsaturated aliphatic fatty acids, such as oleic acid, linoleic acid and linolenic acid, inhibit 5-alphareductase activity. Linolenic acid is a potent inhibitor of 5-alpliareductase. But if its in vitro efficacy is satisfactory, the results of topical treatment of the scalp of patients with alopecia are disappointing (US 6696484 to Liao et al, see column 33, lines 60 to 67); probably because the cutaneous absorption of linolenic acid is very small, and is limited at the stratum corneum (Aarti Naik et al, J. Control. Release, 1995 37 ₅ 299-306), this on the one hand. On the other hand, the enzyme 5-alphareductase is localized in the epidermis; mostly in the sebaceous glands, as well as in the hair follicles.

Moreover, it is a question of bioavailability of linolenic acid when applied topically to the scalp. Bioavailability is conditioned by the galenic formulation. Microemulsions thus allow a significant increase in the bioavailability of lipophilic active principles compared to traditional forms.

The inventor has discovered quite surprisingly and unexpectedly that the incorporation of sunflower oil and fatty acids into cosmetic compositions in the form of microemulsion of the oil-in-water type, made it possible to successfully treat the alopecia. Hair growth can be stimulated by the topical application of a microemulsion composition containing at least one long chain polyunsaturated vegetable oil.

Compositions in microemulsion form are known in the art. Understandably, these microemulsions have several advantages such as ease of absorption, delivery and bioavailability of active ingredients (Kreilgaard, Advanced Drug Delivery Reviews, 2002, 54 Suppl. I ₃ S77-S98).

Detergent compositions in the form of microemulsions are known in the art and are described, for example, in US Pat. No. 6,191,090 to Mondin et al .; 5716925 de Mondin et al; 5616548 of Thomas and putres; 5597792 to Klier and others; 5415813 to Msselyn et al; 5523014 of Dolan and others; 4909962 to Clark; 4540448 of Gauteer and others; 4561991 to Herbots et al; 4472291 to Rosario; 3723330 of Sheflin. Other references which relate to emulsions which contain solvents, WO 2002/102327 to Hua et al; the British patent

GB 2144763A to Herbots et al; European patents EP 0137615 and EP 0137616 to Herbots et al .; EP 0160762 to Johnston et al. All of these patents are incorporated by reference in the present invention.

Other references which describe microenalions that contain solvents, WO 99/9121 to Mondain et al; WO 99/6520 to Kaler et al and WO 98/35007 to Leonard and Drapier.

These documents describe oil-in-water emulsions or microemulsions that contain hydrocarbons or esters or mineral oils. These disclosures teach that these emulsions or microemulsions contain additives to improve the transparency of the formulation, such as lower C ₁ -C ₈ alcohols such as ethanol and isopropanol, glycols such as propylene glycol and glycol. These solvents have the sole function of stabilizing the composition. They increase the cost of formulation of these compositions without benefiting cleaning performance.

In addition, this approach is in itself ineffective for preparing emulsions containing dispersed oil in large quantities. The higher the amount of oil, the higher the concentration of solvent required to maintain said oil solubilization is high, more skin irritation may occur. The solvent has an affinity for the aqueous phase, its migration into the aqueous phase could then cause the separation of the composition in phase by decreasing the overall solubilizing power. What is needed is a substantially solvent free in-emulsion composition. The benefits of vegetable oils are well known, especially when it comes to care of hair fibers. However, the incorporation of vegetable oils, in order to benefit from their benefits, in the current detergent compositions leads to unstable formulations following the separation of the oil from the rest of the composition.

It will be readily appreciated that technical problems associated with the formulation of microemulsioms comprising long chain triglycerides are very different and more complex than those encountered in the manufacture of emulsions containing hydrocarbons, esters or mineral oils. .

Microemulsions comprising long chain triglycerides such as sunflower oil are non-trivial. We can refer to the works of Alander and Warαheim, J. Amer. OR Chem. Soc., 1989, 66, 1656-1660 and those of Gaonkar and Bagwe, Surfactant Science Series, 2003, 109, 407-430.

Several attempts to incorporate high molecular weight triglycerides into cleaning compositions have included the emulsion or microemulsion of such glycerides. In this regard, many non-conventional surfactants have been proposed among which alkylpolyglycosides, silicone surfactants, alkali salts of cetylphosphate and palmitoyl sarcosinate, alkyl ether citrates, unsaturated fatty acid esters of polyoxyethylene sorbitol, phospholipids and block copolymers.

For example, a method for providing long chain triglyceride emulsions utilizes phospholipids as surfactants. Such compositions are found in U.S. Patent 5152923 to Weder. These emulsions have the disadvantage of being unstable in storage and the compositions turn yellow and produce rancid odors. US5858954 of Baker, published January 12, 1999, mentions that the emulsion can be performed with alkylpolyglycoside surfactants which avoids the use of solvents. This publication also mentions that it is generally not possible to prepare emulsions of long chain triglycerides with nonionic surfactants of alcohol ethoxylate type without the use of solvents such as alcohols, glycols, amines (see Column 1, lines 60 to 65).

WO 98/47464 to Franco and Heine discloses that aqueous oil-in-water emulsions containing fatty alcohol ethoxylates and long chain triglycerides have a short shelf life (four weeks) and that they tend to to separate in phase.

US Patents 6120778 and 5958433 and WO 2004/50045 all deal with stable microemulsions comprising silicone surfactants and long chain triglycerides. However, the silicone surfactants do not have a very good washing action and their foam resistance is not particularly good.

The document WO 02/056843 (Oréal) describes a microemulsion of oils, with a molecular weight greater than 400, characterized in that it contains a ternary system of surfactants comprising a mixture of an ethoxylated fatty ester, a fatty acid ester sorbitan, the alkali salts of cetylphospliate and the alkaline salts of palmitoyl sarcosinate. The document mentions that a nanoemulsion is obtained only with the alkaline salts of cetylphosphate and palmitoyl sarcosinate (see Table 1, page 15). This document also mentions that emulsions comprising long chain triglycerides and ionic surfactants, conventionally used in cosmetics, are unstable. T / MA2007 / 000011

Another method for the microemulsification of triglycerides is found in US Patent 6413527 to Simonnet et al (Oréal), which teaches the use of citrated alkyl ether derivatives as essential surfactants in the composition.

Additional references to oil-in-water microemulsions including long chain triglycerides and non-conventional surfactants include US Patent No. 6464990 to Simonnet et al; and International Patent Application WO 2005/020939 of Huang et al. WO 2005/020939 (Unilever) mentions that long chain triglycerides are notoriously difficult to microemulsify (see page 1, lines 28 to 35 and page 21, lines 1 to 10).

U.S. Patent No. 3954658, instructed on a method for stabilizing oil-in-water emulsion triglycerides using from 60 to 80% by weight of unsaturated polyoxyethylene sorbitol fatty acid esters and 0.5 1% by weight of alkaline salts of fatty acids. This document also mentions the difficulty and instability of enemaulsions containing high weight triglycerides and conventional surfactants (see Column 1, lines 24 to 34).

US3808311 of Frank et al., Published April 30, 1974, discloses emulsion shampoo compositions comprising from 15% to 68% by weight of surfactant materials consisting of a mixture of amphoteric, cationic surfactants and alkyldimethylamine oxides. However, this description is limited to less than 2% by weight of the olive oil. With an amount greater than 2% by weight of the olive oil, the composition separates into two distinct phases for a very short period of rest. Some of these methods require vigorous stirring and high-pressure homogenization steps to obtain microemulsions with cells smaller than 150 nm in size.

Although these patents disclose compositions containing ernulphide oils, they are not entirely satisfactory in terms of cleaning for various reasons. These compositions are essentially based on nonionic surfactants which are characterized by a low foaming power compared to that of anionic surfactants. At higher concentrations, the nonionic surfactants form a liquid phase containing water droplets. These liquid phases have proved unsuitable as cleaners because they do not disperse easily in water but tend to form gels after dilution.

A second problem relates to the preparation of oil-in-water microemulsion detergent compositions, free of solvents, having good cleaning properties and which are based on conventional surfactants, in particular anionic surfactants and nonionic surfactants.

The prior art teaches that emulsions comprising long oil-in-water chain triglycerides are unstable when the fatty alcohol ethoxylate nonionic surfactants are used alone or in combination with conventional surfactants. The prior art has also recognized the difficult and non trivial nature of the microemulsification of high molecular weight triglycerides.

There is still a need for a microemulsion composition, which successfully incorporates long chain triglycerides and conventional surfactants, and has good stability. An object of the present invention is therefore to formulate stable aqueous microemulsions containing fatty alcohol ethoxylate nonionic surfactants which are substantially free of alcohols and solvents.

Therefore, it is still necessary in the art to have a microemulsion detergent product free of alcohols and solvents. Also, in the technique needs a detergent microemulsion containing a triglyceride long chain ¹ having a high storage stability and having acceptable cleaning properties and conditioning.

It has now surprisingly been found that stable oil-in-water microemulsion compositions comprising long chain triglycerides can be prepared from conventional surfactants such as fatty alcohol ethoxylates and acid salts. fat. Microemulsions according to the invention do not require the presence of solvents which are usually undesirable for aesthetic reasons (odor) and for toxicity reasons.

The present invention relates to transparent and stable microemulsions comprising an oily phase dispersed in an aqueous phase which does not comprise lower alcohols and / or solvents, thus allowing its application to sensitive skin.

Another object of the present invention is to provide oil-in-water type microemulsions containing long chain triglycerides which are substantially free of solvents which are thus aesthetically and stabilityally acceptable. Another object of the present invention is to provide compositions for treating alopecia and preventing hair loss. Still another object of the present invention is to provide compositions in the form of microelulsions to stimulate hair growth.

It is also an object of the present invention to provide a method of regulating hair growth which comprises applying a composition as defined herein to the hair or scalp.

The invention more particularly relates to a method of treating alopecia, characterized in that it consists in applying to the scalp a composition in the form of microemulsion according to the invention, then perform a rinsing with water , after a possible break time.

Another object of the present invention is to provide compositions in the form of microemulsions for simultaneously cleaning and conditioning of keratin materials such as hair and skin.

These and other aspects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description in which, unless otherwise indicated, all percentages are by weight.

To summarize the invention, one could say that it! relates to an oil-in-water microemulsion composition for the treatment of alopecia and for the cleaning and conditioning of keratin materials, composition having a better stability and comprising: a) from about 1% to about 40% by weight; weight of salts of fatty acids;

11 b) from about 1% to about 30% by weight of at least one nonionic surfactant; c) from about 0.01% to about 20% by weight of at least one natural or synthetic microemulsion oil; d) from about 0% to about 15% by weight of free fatty acids C ₈ -C ₂ 2; e) from about 10% to about 95% by weight of water; f) from about 0.1% to about 10% by weight of a wetting agent; g) from about 0.1% to about 10% by weight of an electrolyte; h) from about 0.1% to about 20% by weight of other ingredients; and i) 0% to about 30% of a water-soluble additive selected from the group consisting of lower amides having at most 6 aliphatic carbon atoms and mixtures thereof.

According to a preferred embodiment of the present invention, the composition comprises at least one vegetable oil containing triglycerides of long chain and unsaturated fatty acids. According to a preferred embodiment of the invention, the composition is in the form of a microemulsion of oil-in-water type.

By microemulsion means here an emulsion whose droplet size is less than a hundred nanometers. Oil-in-water microemulsions according to the invention contain water as a continuous phase. The oily phase (dispersed phase) is in the form of finely divided droplets in the aqueous phase. The average size of the oil globules is less than 400πnn, preferably between 30 and 150 nm, and even more particularly between 50 and 100 nm.

The compositions according to the present invention comprise from 10 to 95% water, preferably from 20 to 70%, more preferably from 25 to 60% by weight of the total composition. Microemulsions in the diluted state may contain larger amounts of water. Deionized water is preferably used.

The amount of the oily phase in the composition of the invention may range, for example, from 0.01 to 20% and preferably from 4 to 10% by weight relative to the total weight of the composition. Moreover, the compositions according to the invention may contain a large percentage of oil and while being perfectly stable and without leaving a greasy feeling after use.

Microemulsified oils

The oils which can be used in the present invention can be chosen from the group consisting of vegetable oils, waxes, animal oils, mineral oils, synthetic oils, fatty acid esters such as isopropyl myristate and silicones. insoluble in water, sorbitan fatty esters, lanolin and lanolin derivatives, and mixtures thereof.

According to a particularly preferred embodiment of the present invention, the composition is characterized in that the oily phase in microemulsion comprises at least one fatty acid ester of polyols and / or a fatty acid ester of an ether polyol which contains at least one free hydroxyl group such as 1,2-isopropylidene glycerol.

The term "polyol" is understood here to mean any aliphatic compound containing at least two free hydroxyl groups. For example, suitable polyols may be chosen in the following cases: linear aliphatics, straight or branched chain, saturated or unsaturated. This group includes in particular glycerol, ethylene glycol, propylene glycol, butylene glycol, 1,3-dihydroxyacetone, and mixtures thereof. As esters of C ₈ -C ₂₄ fatty acids of polyol, homogeneous esters or mixed esters of polyol of C ₈ -C ₂₄ fatty acids are preferred. In a preferred embodiment of the invention, the fatty acid ester can be selected from fatty acids of Cs to C24, preferably C12-Qs, in particular fatty acids, C _18, such as stearic acid, oleic acid, linoleic acid, liaolene acid or mixtures thereof.

Examples of fatty acid esters C§ -C ₂₄ esters which are obtainable by reacting glycerol or î'étîiylèneglycol on fatty acids Cs

C ₂ 4, and are contained for example in vegetable oils.

As vegetable oil, there may be mentioned argan oil, wheat germ oil, borage oil, evening primrose oil, olive oil, sweet almond oil , palm kernel oil, coconut oil, babassu oil, sunflower oil, corn oil, corn germ oil, melon seed oil, oil rapeseed, castor oil, sesame oil, pine oil, soybean oil, almond oil, avocado oil, black seed oil, oil of croton, grapefruit seed oil, grape seed oil, hazelnut oil, macadamia oil, palm kernel oil, safflower oil, peanut oil, nutmeg oil, walnut oil, pistachio oil, pumpkin oil, rice bran oil, watermelon seed oil, palm oil, apricot kernel oil, avocado oil and mixtures thereof.

In accordance with the present invention, the glycerol esters may be selected from the group consisting of triglycerides or diglycerides or monoglycerides or phospholipids or mixtures thereof. A glyceride ester may contain one to three fatty acid moieties, preferably C ₁₀ -C ₂₂ fatty acid moieties. Phospholipids, for example lecithins, may be selected from the group consisting of natural lecithin, synthetic lecithin, and mixtures thereof. The term "lecithin" in the context of this invention refers to glycerol esters wherein two alcohol functions are esterified with fatty acids and the third by a phosphorylcholiαβ group.

In a preferred embodiment of the composition for treating hair loss, microemulsions are preferred which comprise free oils whose iodine number is greater than 50, more preferably greater than 90, more preferably still higher than at 130, and most preferably above 150.

According to a particularly preferred embodiment of the present invention, the composition intended for the treatment of alopecia is characterized in that it comprises at least one microemulsion vegetable oil, preferably a mono and / or polyunsaturated vegetable oil which contains a significant number of unsaturations. Sunflower oil, wheat germ oil, argan oil and olive oil are preferred. It is also preferred to use a mixture of two or more oils. Particularly preferred is sunflower oil and / or argan oil, sunflower oil being particularly preferred.

By polyunsaturated oil is meant a triglyceride whose majority of linear carbon chains have two or three double bonds per chain, noted

C18: 2 or C18: 3.

The term vegetable oil used in the present invention includes oils from oleaginous plants, such as sunflower oil, olive oil, argan oil, corn oil. Salts of fatty acids

The salts of fatty acids that may be used in the present invention are straight or branched, saturated or unsaturated, natural or synthetic, or mixtures thereof. Said fatty acid salts include alkaline salts such as sodium, potassium and / or lithium salts as well as ammonium and / or alkylammonium salts of fatty acids.

A particularly preferred class of branched-chain fatty acid salts useful in the present invention include the secondary (monosubstituted on the 2-carbon) carboxylates of the formula ## STR2 ## wherein R ¹ and R ² are alkyl or alkenyl groups and the sum of the carbon atoms in R ¹ and R ² is from 8 to 16.

By way of illustration, but without limitation, precursor acid compounds include 2-methylundecanoic acid, 2-ethyldecanoic acid, 2-propylnonanoic acid, 2- butyloctanoic acid, 2-propyldecanoic acid, 2-butylnonanoic acid, 2-pentyloctanoic acid, 2-methyldodecanoic acid.

Still another class of branched chain fatty acid salts contains the C 10 -C ¹⁸ tertiary monocarboxylate compounds, for example the neo carboxylates, of the formula R ³ CR ⁴ (R ⁵ ) CQOM, in which the sum of the carbon in R ³ , R ⁴ and R ⁵ is 8 to 16.

The straight-chain fatty acid salts contain 8 to 24 carbon atoms, preferably 8 to 20, more preferably 8 to 18. Particularly useful are the sodium and potassium salts of the fatty acid mixtures thereof. of coconut oil and long chain glycerides of vegetable or animal origin. The straight chain fatty acid salts used in the compositions of the present invention are salts consisting preferably of fatty acid mixtures derived from coconut oil and long chain glycerides of vegetable or animal origin. The coconut oil and glycerides are used in ratios of 95: 5, 90:10, 85:15, 80:20, 75:25; the preferred ratios are from about 80:20 to 60:40.

According to a preferred embodiment of the invention, mixtures of fatty acid salts comprise about 55% to 95% by weight of sodium salts of coconut oil fatty acids and about 0.1% to 40% by weight of coconut oil. weight of sodium salts of fatty acids of a vegetable oil having an iodine value greater than 50, although other types of fatty acid salts may be used. These mixtures contain about 90% by weight of fatty acid salts having carbon chain lengths in the Cn to Qg range.

Other oils such as palm kernel oil and babassu oil may also be used in the present invention in place of or in conjunction with coconut oil.

Palm kernel oil or babassu oil contains a similar distribution of fatty acids to that of coconut oil. The coconut oil contains mixtures of fatty acids that have an approximate carbon chain length distribution of about 7.6% C ₈ , 6.6% Ci ₀ , 47.1% C 12, 17 , 2% of C _4, 8.2% C _J6, 3.4% of C _8, 6.3% oleic acid and 2.6% of linoleic acid (the first six listed being saturated).

The concentrations of critical aggregations (cac) of linear aliphatic-chain sodium alkanoates of formula RCOONa, for R comprising 9, 10, 11, 12, 13 and 14 carbon atoms are respectively 106, 38, 31, 12, 9, and 3.8 mM (Sheth and Subrahmanyam, J. Indian, Chem Soc, 1982, 59, 860). On the other hand, the cac values of sodium p-hexylbenzoate and p-octylbenzoate sodium are respectively 48 and 130 mM (Moroi and Sakamoto, J. Phys Chem, 1988, 92 _S 5189). By comparing these cac values with alkanoates and alkylbenzoates, it is clear that the phenyl group is equivalent to four methylene groups.

As a result, another class of monocarboxylate compounds useful in the present invention includes carboxylates of the formula R ⁶ -R ⁷ -COOM wherein R is C ₅ -C ₁₀ alkenyl or alkenyl, and R is a cyclic structure, such as benzene, cyclopentane, cyclohexane and the like (Note: R ⁶ may be ortho, meta or para when the ring is phenyl). As an example of this family, mention may be made of sodium p-octylbenzoate and sodium 4-pentylcyclohexanecarboxylate.

The fatty acid salts used in the microemulsions according to the invention may be prepared by direct saponification of fats and / or oils or by neutralization of the free fatty acids which are prepared according to a separate manufacturing process. Saponification can be carried out by conventional boiling boiling processes or continuously operating processes. The neutralization of the fatty acids can be carried out with the appropriate alkali or alkylamines or alkanolamines such as rethanolamine, diethanolamine, and triethanolamine or mixtures thereof. As the alkali, there may be mentioned, but not limited to, sodium hydroxide, potassium hydroxide, ammonium hydroxide, or mixtures thereof.

To form the fatty acid salts according to the present invention, it is preferred to direct saponification micellar phase of fats and / or oils, characterized in that it comprises reacting together at a temperature of about 4O ⁰ At about 90 ^° C., an oily phase comprising at least one vegetable oil, an aqueous phase comprising an alkali and an electrolyte, and in the presence of at least one nonionic surfactant. The alkali may be selected from hydroxides of sodium, potassium, ammonium, or mixtures thereof, or 00011

can be replaced by an enzyme such as lipase. Sodium hydroxide is especially preferred.

Ionic name surfactants

The composition according to the present invention further contains, as essential compound, at least one nonionic surfactant. Nonionic surfactants which can be used in the present application are made from at least one mole of alkylene oxide, especially propylene oxide or ethylene oxide, with a compound containing at least 6 carbon atoms and an active hydrogen atom. Compounds which can be condensed with alkylene oxide include phenols, aliphatic alcohols, sorbitan, glycerols, glycols and polyglycols, alkylamines, alkanolainines, mercapto-functional compounds such as dodecyl, and the like. mercaptan, roleyl mercaptan and cetyl mercaptan, tliiophenols and thionaphthols, amides, acids, sulfonamides.

Among these nonionic surfactants, particular mention must be made of alkylphenols or alkoxylated fatty alcohols, preferably alkoxylated with ethylene oxide or mixtures of ethylene oxide and propylene oxide; polyglycol esters of fatty acids or fatty acid alcohols; ethylene oxide / propylene oxide block polymers; glycerol esters such as monoglycerides, esters of glycerol polyesters; sorbitol and sorbitan esters and mixtures thereof.

According to a particularly preferred embodiment of the present invention, use is made of nonionic surfactants such as alkyl ethoxy alcohols (AE) and ethoxylated alkylphenols. The alkylethoxy alcohols are products of the condensation of saturated or unsaturated straight chain or branched chain aliphatic alcohols with ethylene oxide. The alkyl group of the alcohol has from about 6 to about 20, preferably from about 9 to about 15 carbon atoms. carbon. For surfactants AE, the average degree of ErnOxyTarioή is from 0 to 20, preferably from 1 to 15, and more preferably from 2 to 15, most preferably from 2 to 12.

For the alkylphenol ethoxylates, the alkyl group contains about 6 to 16 carbon atoms and straight or branched chain, with about 4 to 25 moles of ethylene oxide per mole of alkylphenol.

Particularly preferred ethoxylated nonionic surfactants have HLB (hydroplle-lipophilic balance) below 16, preferably below 15, more preferably below 14, especially from 11 to 14.

A preferred class of nonionic ethoxylates is represented by the surfactants of the Neodol series of formula R (OCH ₂ CH ₂ ) _n OH (available from Shell). Suitable nonionic surfactants for use in the present invention are Neodol 45-7 (HLB = 1.6, R is a mixture of C _1-4 alkyl chains and C _1-5 , n is 7), or Neodol 23-6.5 (HLB = 12; R is a mixture of alkyl chains Cl ₂ and Cu, n is 6.5), or Neodol 25-7 (HLB = 2.3; R is a mixture of C ₁ and C ₁₅ alkyl chains, n is 7), or Neodol 91-6 (HLB = 12.4; R is a mixture of C ₉ and C ₉ alkyl chains; is 6), or Neodol 91-5 (HLB = 1.6, R is a mixture of C ₉ and C ₉ alkyl chains, n is 5), or mixtures thereof. Neodol 91-6 and Neodol 25-7 are preferred here.

Of the family of ethoxylated alkylphenols, polyoxyethylene (9) nonylphenyl ether such as Tergitol NP-9 and Igepal CO-630 is preferred.

Propoxylated nonionic surfactants and ethoxylated / propoxylated nonionic surfactants may also be used in the present invention in place of ethoxylated nonionic surfactants as defined above or together with said surfactants. Semi-polar nonionic surfactants such as water-soluble amine oxides, water-soluble phosphine oxides, water-soluble sulfoxides, wwitterionic surfactants, or mixtures thereof, can also be used in the present invention in place of the agents. ethoxylated ionic surfactants as defined above or together with said surfactants.

Oxides of amines ^! The water-soluble salts contain an alkyl chain of 10 to 18 carbon atoms and two chains selected from the group consisting of alkyl groups and hydroxyalkyl groups containing from 1 to 3 carbon atoms. The water-soluble phosphine oxides contain an alkyl group of 10 to 18 carbon atoms and two chains selected from the group consisting of alkyl groups and hydroxyalkyl groups containing from 1 to 3 carbon atoms. The water-soluble sulfoxides include an alkyl group of 10 to 18 carbon atoms and a chain of 1 to 3 carbon atoms selected from the group consisting of methyl groups and hydroxyalkyl groups. i

The compositions of this invention comprise from 0.1 to about 30% by weight of nonionic surfactant, preferably from about 5% to about 30%, more preferably from about 10% to about 20%.

Incorporation of the nonionic surfactant in the compositions of the present invention prevents frothing (Αntonenko et al., Colloid Journal, 2002, 64, 523-526). In addition, the nonionic surfactant contributes to the effectiveness of fatty acid salts in hard water by the complexation of calcium ions. Also, such a combination is particularly advantageous because the fatty acid salts and the nonionic surfactant act synergistically (Theander and Pugh, J Colloid Interface Sd 2003, 267, 9-17). Fatty acids

The compositions of the invention also preferably contain from about 0.1% to about 10% by weight, more preferably from about 1.5% to about 5% by weight of fatty acids having a chain of from 8 to 24 carbon atoms. carbon, straight or branched chain, saturated or unsaturated. The fatty acids are added as such or prepared in situ by the addition of an acidic compound, for example lactic acid, to convert the fatty acid salts present in the composition. In a preferred embodiment of the invention, the fatty acid may be selected from: fatty acids, of C ₂ to Cig, for example, from the acid group consisting of ^', palmitoleic, oleic acid, elaidic acid, acid linoleic, linolenic acid, and arachidonic acid. In a particularly preferred embodiment of the invention, stearic acid is used with linoleic and oleic acids in an amount of from 0.1% to 10% by weight.

Preferably, according to the present invention, the free fatty acids can be produced with an in situ reaction of an acidic compound with said fatty acid salts. This acidic compound, which may be organic or inorganic, is preferably water-soluble with a pKa of about 6, more preferably a pKa of less than 5 ^.

Preferably, the acid compound is, as non-limiting examples, an organic acid selected from the group consisting of lactic acid, citric acid, acetic acid, glycolic acid, acid and the like. aspartic acid, thiolactic acid, thioglycolic acid or mixtures thereof.

Advantageously, according to the present invention, the very short chain alkylbenzenesulfonyl acids or mixtures thereof are used as acidic compounds. Indeed, the reaction of these acids with the fatty acid salts produces alkylbeinzenesililonates of very short chain such as the 000011

sodium xylenesulfonate, sodium toluenesulfonate. Sodium xylenesulfonate is representative of hydrotropic agents.

Hydrotropes are capable of strongly promoting the solubilization of substances in aqueous systems in which said substances are practically insoluble. Hydrotropes are used in liquid detergents to prevent precipitation at low temperatures and to break any gelled structures. Therefore, hydrotropes are stabilizing ingredients.

According to the present invention, the amount of said acidic compound has been estimated so that a portion of the fatty acid salts whose chains contain 18 carbon atoms are converted into corresponding fatty acids; these salts are characterized by a pBLa> 9 (see Table 1). The fatty acids that may be formed during this stage are stearic acid, oleic acid and linoleic acid.

Table 1: pka of fatty acids (Kanicky et al., J. Colloid Interface Sd., 2002, 256, 201-207 Qt.Langmuir, 2000, 16, 172-177)

MA2007 / 000011

The presence of fatty acids in the compositions of the present invention makes it possible, among other things, to sufficiently lower the interracial tension (Kanicky - and-others, langmiur, 2000, 16, 172-177), to improve the performance cleaning and thus increase the stability of the microemulsion.

Faumidification Agent

The compositions of the present invention may contain one or more moisturizing or hydrating agents for the hair or skin. The preferred proportion of the wetting agent is about 0.1% and about 10% by weight. In preferred forms, the humectant is selected from water soluble polyols and essential amino acid compounds. Glycerol is especially used in the compositions according to the present invention.

Electrolytes

The compositions according to the present invention also comprise, as an essential element, a small amount of electrolyte. In fact, the excess of salt results in the turbidity of the composition and / or the separation of the phases.

The term "electrolyte" is used herein to define a soluble compound in

[the water that dissolves in the composition. According to the present invention, the electrolyte

I may preferably contain any salt, mineral or organic,

hydrosoluble. Suitable examples of electrolytes include chloride

^! of sodium or potassium, sodium citrate, sodium lactate, acetate

; of sodium, very short chain alkylbenzenesulfonates or mixtures thereof.

The preferred salt suitable in the present invention is sodium chloride I and / or sodium lactate and / or sodium thiolactate and / or sodium thioglycolate and / or sodium salts of very short chain alkylbenzene sulfonates. The amount of the electrolyte in the final composition according to the present invention is from about 0.1% to about 10% by weight, preferably from about 0.1% to about 5%. chelators

The present detergent compositions may also optionally contain one or more iron and / or manganese chelating agents. These chelating agents may be selected from the group consisting of aminocarboxylates, aminophosphonates, polyfunctionally substituted aromatic chelating agents, and mixtures thereof.

According to the present invention, a chelating agent selected from the group consisting of ethylenediaminetetraacetic acid and its derivatives and salts is preferred. These chelators can be incorporated in the present compositions in an amount of from about 0.1% to about 5% by weight, preferably from about 0.1% to about 2%, more preferably about 0.1%. about 0.5%.

Optional Ingredients

The compositions in the microemulsion form of the present invention may comprise a variety of optional ingredients. Suitable optional ingredients for use in the present invention include other surfactants, adjuvants, polymers, bactericides, antioxidants, solvents, pigments, dyes, and fragrances. The amounts of these different ingredients are from 0.01% to 20% of the total weight of the composition. Said ingredients and their concentrations must be such that they do not modify the desired property for the composition of the invention.

Other surfactants which may be used in the present invention are amphoteric surfactants, anionic surfactants, zwitterionic agents, cationic surfactants and mixtures thereof. Said surfactants may be present in the compositions according to the present invention in an amount of from 0.1% to 20% by weight of the total composition, preferably from 0.1% to 10% and more preferably from 0.1% to 5% by weight. %. Although they are not preferred; anionic surfactants such as alkyl sulphates and alkyl ether sulphates may be included in the compositions of the present invention.

It is also possible to incorporate different vitamins into the compositions of the present invention. For example, vitamin A and its derivatives, ascorbic acid, vitamin B, biotin, pantothenic acid, vitamin D and mixtures thereof can be used.

The present invention also relates to a method of manufacturing the microemulsions described herein.

A preferred process for preparing the composition of the invention comprises: forming an oily phase containing at least coconut oil and / or palm kernel oil and / or babassu oil, a vegetable oil other than these three oils, and at least one nonionic surfactant, as well as other hydrophobic substances that can be incorporated into the composition.

In the second step, an aqueous phase is prepared which comprises water, at least one electrolyte, a chelator and sodium hydroxide and the other water-soluble ingredients that can be incorporated into the composition.

The aqueous phase is mixed with stirring with the oily phase heated to about 40 ^° C. to about 90 ^° C.

After a time ranging from 5 to 60 minutes, preferably 15 mm, is added, with stirring, an aqueous solution of an acid compound as defined above, followed by the remainder of nonionic surfactant and the oil that is going to be microemulsified.

The following examples describe in more detail and show the preferred embodiments within the scope of the present invention. The examples are provided for illustrative purposes only and without the invention being limited to these examples, since many variations thereof are possible without depart from his mind or his frame. Unless otherwise indicated, all percentages herein are approximate and are by weight.

EXAMPLE 1 In a vessel equipped with magnetic stirring, 50 g of coconut oil and 20 g of Tergitol NP-9 (this mixture constituting the oily phase) are introduced and heated to 80 ° -85 ° C. using a water bath. Then, a solution comprising 9.3 g of sodium hydroxide (predetermined quantity for saponification of about 50 g of coconut oil), 1.6 g of sodium chloride, 0.4 g of EDTA-Na ₂ is added to this mixture. and 65 g of distilled water. The resulting mixture is stirred at 80 ° to 85 ° C for 15 minutes. Subsequently, to the resulting mixture is added a solution comprising 2.5 g of lactic acid 80% in 70 g of distilled water, 8 g of sunflower oil and 20 g of Tergitol NP-9. The resulting mixture is stirred for 15 minutes at a temperature between 80 ° and 85 ° C. The resulting mixture is cooled to room temperature (25 ° C). About 245 g of a turbid composition are obtained.

The approximate percentages of each component in the composition of Example 1 are shown in Table 2.

The cloudy composition of Example 1 was applied hour after hour, becoming transparent after a few days resting at room temperature (about three days). Similar cases have been described in Kralchevsky and Denkov, "Molecular Interfacial Phenomena of Polymers and Biopolymers" Woodhead Publishing, Cambridge, UK _5, 2005; Chapter 15, pp. 538-579. According to this reference, the solubilization of the oil is the term given to changes occurring spontaneously with time in an enralsion comprising triolein and nonionic surfactants. This is due to the tendency of the globules to reorganize and lead to a decrease in the size of the globules and the number of aggregations, which stabilize for three days. For cell sizes below 400 nm, the composition becomes transparent. Table 2: Example 1 composition in the form of microemulsion

component Percentage by weight

Free sunflower oil 3,26

Free fatty acids * 2,51

Glycerin ** 2.04 fatty acid sodium salts of copra oil *** 19.84

Tergitol NP-9 16.32

Sodium lactate 1,02

Sodium chloride 0.65

EDTA-Na ₂ 0.16

Water 54.20

* Fatty acid mixture comprises about 27.64% stearic acid, 51.22% oleic acid and 21.14% linoleic acid.

** Quantity of glycerine formed in situ during the hydrolysis of coconut oils. *** Mixture of sodium salts of fatty acids comprises about 9.0% of Cg, 7.6% of C ₁ O ₃ 53.7% of Ci ₃ , 19.4 of Ci ₄ , 10.3% of Ci ₆

The composition of Example 1 comprises fatty acid salts derived from coconut oil alone. More preferably, salts of coconut oil derived fatty acid mixtures and long chain glycerides of vegetable or animal origin are preferred.

The fatty acid salts used in the compositions of the examples which follow are salts consisting, preferably, of fatty acid mixtures derived from coconut oil and long chain glycerides of vegetable or animal origin. The coconut oil and glycerides are used in ratios of 95: 5, 90:10, 85:15, 80:20, 75:25; the preferred ratios are from about 80:20 to 60:40. An approximate distribution of the carbon chain length of the coconut oil fatty acids and some preferred oils of the present invention is shown in Table 3.

Table 3: Fatty acids of coconut oil, sunflower oil, argan oil and olive oil

Length of coconut oil Argan oil Olive oil Sunflower oil chain% by weight% by weight% by weight% by weight

C8 7.6

ClO 6.6

C12 47.1

C14 17.2

C16 8.2 13.5 10.7 6.2

C18 3.4 5.5 3.9 4.5

C18: l 6.3 46.2 75.3 19.4

C18: 2 2.6 32.1 7.6 65.3

C18: 3 0.1 0.2 I ₅ O 1.0

In the following examples, the compositions in the form of microemulsions were carried out by the following general procedure: 25 g of sunflower oil, 40 g of coconut oil and 20 g were introduced into a vessel equipped with magnetic stirring. of Neodol 91-6 (this mixture constitutes the oily phase) which is brought to a temperature of about 80 ⁰ C to about 85 ⁰ C using a water bath. Then, a solution comprising 10.6 g of sodium hydroxide (a predetermined amount for saponifying about 40 g of coconut oil and 21 g of sunflower oil), 1.6 g of sodium chloride, is added to this mixture. 0.4g of EDT A-Na ₂ and 77 g of distilled water. The resulting mixture is stirred at a temperature of about 80 ⁰ C to about 85 ° C for 15 minutes. Subsequently, to the resulting mixture is added a solution comprising 3 g of lactic acid (80%) in 90 th of water 00011

distilled (to form in situ free fatty acids pka> 9, in this case stearic acid and oleic acid), then 14g of sunflower oil and finally 25g of Neodol 91-6. The resulting mixture is stirred for 10 minutes at a temperature of about 80 ⁰ C to about 85 ° C. The resulting mixture is cooled to room temperature (25 ° C). About 305 g of a composition (Example 2) in the form of oil microemulsion in transparent and stable water are obtained. The approximate percentages of each constituent in the composition of Example 2 are shown in Table 4.

Table 4: Example 2 Composition in microemulsion form

* Fatty acid mixture comprises about 30.86% stearic acid and 69.14% oleic acid,

** Amount of glycerine formed in situ during the hydrolysis of the oils of the composition.

*** Mixtures of mono- and / or di-glycerides.

**** Blend of coconut oil / sunflower oil mixed sodium salts in a 65:35 weight ratio and has an approximate carbon chain length distribution of 5.9% C ₈₃ 5.1% C10, 36.2% C ₁₂ 13.0% C _14, 8.6% C _16,

2.6% sodium oleate, 28.1% sodium hydrogenate. The microemulsion according to Example 2 contains sodium salts of fatty acids derived from coconut oil and sunflower oil in the ratio of about 65:35. Lactic acid may be replaced by an equivalent molar concentration of any other water-soluble acid compound, and mixtures thereof. The amount of the nonionic surfactant is incorporated in two stages; at the beginning of the formulation, said oily phase may comprise said surfactant in an amount of from 0.5% to 40% by weight of the oily phase, preferably from 8% to 30% and more preferably from 13% to 30%.

Compositions comprising microemulsion vegetable oils are prepared according to the same general procedure as that used to prepare the microemulsion shown in Table 4.

Example 3

Example 3 is identical to Example 2, except for the presence of the nonionic surfactant Tergitol NP-9 in place of Neodiol 91-6.

Example 4

A composition in the form of a microemulsion of oil in water is prepared according to Example 2 with the only difference that Ig of lactic acid has been replaced by 1.7 g of p-toluenesulphonic acid.

Example 5

Example 5 is identical to Example 4, except for the presence of the nonionic surfactant Tergitol NP-9 in place of Neodol 91-6.

Example 6

A microemulsion composition of oil in water is prepared according to Example 2 with the only difference that p-toluenesulfonic acid is used at an equivalent molar concentration and instead of lactic acid. Example 7

Example 7 is identical to Example 6, except for the presence of the nonionic surfactant Tergitol NP-9 in place of Neodol 91-6.

Example 8

A composition in the form of microemulsion oil in water is prepared according to Example 2 with the only difference that argan oil is used in place of sunflower oil.

Example 9

A composition in the form of microemulsion oil in water is prepared according to Example 2 with the only difference that olive oil is used in place of sunflower oil.

Example 10

The composition of Example 2 is modified by lowering the proportion of the nonionic surfactant to 13.79% by weight and increasing the proportion of sunflower oil to 4.82% by weight. which corresponds to the addition in the last step of 80 g of distilled water instead of 90 g and 20 g of nonionic surfactant instead of 25 g. This gives a transparent and stable microemulsion.

Example 11

The composition in the form of microemulsion oil in water is prepared according to the general procedure used to prepare Example 2, with the only difference that 25 g and 10 g of olive oil are used respectively instead 25 g and 14 g of the sunflower oil and that the proportion of the nonionic surfactant added in the last step is reduced to 16 g; which corresponds to a proportion of nonionic surfactant of about 12% weight of the composition. Said composition has excellent washing properties, conditioning keratinous substances such as skin and hair.

Example 12

Example 12 is identical to Example 11, except for the presence of Tergitol PEP-9 nonionic surfactant in place of Neodol 91-6.

Ie 13

25 g of sunflower oil, 40 g of coconut oil and 25 g of Tergitol NP-9 (the oily phase) are introduced into a vessel provided with magnetic stirring and are heated to a temperature of about 80 ° C. C at about 85 ° C using a water bath. Then, a solution comprising 10.6 g of sodium hydroxide, 1.6 g of sodium chloride, 0.4 g of DTA-Na ₂ and 77 g of distilled water is added to this mixture. The resulting mixture is stirred at a temperature of about 80 ⁰ C to about 85 ° C for 15 minutes. Subsequently, to the resulting mixture is added a solution comprising 3 g of lactic acid (80%) in 90 g of distilled water, then 17 g of sunflower oil and finally 20 g of Tergitol NP-9. The resulting mixture is stirred for 10 minutes at a temperature of about 80 ^° C. to about 85 ^° C. The resulting mixture is cooled to room temperature. About 308 g of a liquid composition in the form of microemulsion of oil in transparent and stable water are obtained. The liquid composition of Example 13 comprises about 5.5% by weight of microemulsion sunflower oil.

The composition of Example 13 is modified by increasing the proportion of microemulsified sunflower oil to 6.4% by weight (addition in the last step 20g of sunflower oil instead of 17g) and maintaining stirring for 15 minutes, after addition of lactic acid and the other ingredients, instead of 10 minutes. A translucent composition is thus obtained T / MA2007 / 000011

which becomes transparent and stable after a few hours (about 15 hours) at rest at room temperature (25 °).

Example 15

A composition in the form of microemulsion oil in water is prepared according to Example 14 with the only difference that 10g argan oil and 7g of sunflower oil are used in place of 17g of oil of sunflower that is added after the addition of lactic acid.

According to an advantageous variant of the general process above of the present invention, oil microemulsion, in particular vegetable oils and the active ingredients may be incoiporés in the composition at a temperature about 55 ° C to about 60 ⁰ C ₃ and not at 85 ⁰ C as described in said procedure. This mode of incorporation is particularly preferred when one seeks to not affect the integrity of said oils and said active ingredients. In particular the active ingredients and vegetable oils which can be denatured under the effect of heat.

In the following example (Example 16), the composition in microemulsion form was carried out by a variant of the general procedure: 25 g of sunflower oil were introduced into a vessel provided with magnetic stirring. 40 g of coconut oil and 25 g of Neodol 91-6 (this mixture constitutes the oily phase) which is heated at a temperature of about 80 ^° C. to about 85 ^° C. using a water bath. Then, a solution comprising 10.6 g of sodium hydroxide, 1.6 g of sodium chloride, 0.4 g of EDTA-Na ₂ and 77 g of distilled water is added to this mixture. The resulting mixture is stirred at a temperature of about 80 ⁰ C to about 85 ° C for 15 minutes. Subsequently, to the resulting mixture is added a solution comprising 3 g of lactic acid (80%) in 90 g of distilled water, and then cooled to a temperature of about 55 ⁰ C to about 60 ^° C. Then, it is added to this mixture 14g of argan oil and 20g of Neodol 91-6. The resulting mixture is stirred for 15 minutes at a temperature of about 55 ° C to about 60 ^° C. The resulting mixture is cooled to room temperature. About 305 g of a liquid composition are obtained in the form of oil microerosiltration in transparent and stable water.

Even better, the microemulsion oils, in particular the vegetable oils, and the active ingredients can be incorporated into the composition at room temperature (25 °). In the following example (Example 17), the composition in microemulsion form was carried out in two steps: in the first step, a composition is prepared which will be called "phase A" and in the second step, it incorporates the oil at room temperature. Preparation of Phase A: 25 g of sunflower oil, 40 g of coconut oil and 25 g of Tergitol NP-9 are introduced into a vessel fitted with magnetic stirring and are heated to a temperature of about 80.degree. ⁰ C to about 85 ° C using a water bath. Then, a solution comprising 10.6 g of sodium hydroxide, 1.6 g of sodium chloride, 0.4 g of EDTA-Na ₂ and 77 g of distilled water is added to this mixture. The resulting mixture is stirred at a temperature of about 80 ⁰ C to about 85 ⁰ C for 15 minutes. Subsequently, to the resulting mixture is added a solution comprising 3 g of lactic acid (80%) in 90 g of distilled water and 20 g of Tergitol NP-9, and then allowed to cool to room temperature (25 ^° C.). . Example 17 is obtained by mixing 95% by weight of the phase A and 5% by weight of the sunflower oil, with stirring for about 10 minutes at room temperature. The resulting mixture is in the form of a milky and opaque emulsion which becomes clear after about 10 hours at room temperature (25 ° C.).

The emulsion consists of deformable droplets, which can therefore change size, shape, but also number. Gradually, the size of the droplets decreases and the composition becomes transparent. Depending on the concentration of the oil, the composition will take a few hours or even a few days to become transparent; for example 17, the composition becomes transparent after standing for 10 hours at room temperature. This evolution, without energy input, from the milky aspect of the emulsion to transparency is called spontaneous emulsification

According to this procedure of the present invention, an oil-in-water microemulsion comprising a weakly water soluble active ingredient can be prepared. Said active ingredient being solubilized beforehand in an oily phase preferably comprising at least one vegetable oil. As an active ingredient, it is possible to use, according to the invention, vitamins and anti-UV agents. Compositions in microemulsion form are means for improving the bioavailability of active ingredients that are poorly soluble in water.

The microemulsions of the present invention differ from those described in the prior art by their long-term stability and their method of preparation which requires comparatively less energy. Said microemulsions form spontaneously after slight agitation. Spontaneous microemulsification makes it possible to guarantee the stability over time of the compositions according to the present invention.

In the above examples of the present invention, the oil was used in defect with respect to sodium hydroxide. The partial hydrolysis of the vegetable oils according to the present invention leads to 2-monoglycerides since the positions 1 and 3 of the triglycerides are preferentially attacked by the base. Monoglycerides (glycerol monoesters) have two free alcohol functional groups that confer ¹ Some hydrophiïie and emulsifying properties. Although it is not intended to be limited by theory, it appears that the presence of monoglycerides in the compositions of the present invention reduces the interfacial tension of water and oil droplets. This significant reduction in surface tension and the synergistic effect of fatty acids and 07 0000H

Monoglycerides appear to contribute to the stabilization of the microemulsion according to the present invention (Novales et al., Colloids Surf A 2005, 269, 80-86).

The oil-in-water microemulsions described in Examples 1 to 17, according to the present invention, are prepared with moderate agitation and without the high-pressure homogenization step, and are characterized by their storage stability. These microemulsions of oil-in-water type advantageously do not contain organic solvents such as low molecular weight alcohols and hydrocarbons.

The compositions of Examples 2 to 17 of the present invention are transparent and stable. By the term "stable" is meant in the present invention that the compositions of the present invention do not macroscopically separate in separate phases even after a long period of storage at temperatures ranging from 7 to 45 ° C.

Advantageously, the compositions according to the present invention may also contain an additive formed of a water-soluble material, the additive being selected from the group consisting of lower amides having at most 6 aliphatic carbon atoms and their mixtures. Urea is the most preferred additive. Urea is a natural component of keratin materials such as hair and skin. Examples of short-chain urea homologues and analogues, for example formamides and acetamides, are other useful additives. A preferred mixture of lower amides is urea and acetamide.

Example 18: microemulsion oil in water comprising urea 25g of sunflower oil, 40g of coconut oil and 25g of Neodol 91-6 and / or Tergitol NP- are introduced into a vessel provided with magnetic stirring. 9 that is heated to a temperature of about 80 ^° C. to about 85 ^° C. using a bath married. Then, a solution comprising 10.6 g of sodium hydroxide, 1.6 g of sodium chloride, 0.4 g of EDT A-Na ₂ and 77 g of distilled water is added to this mixture. The resulting mixture is stirred at a temperature of about 80 ⁰ C to about 85 ° C for 15 minutes. Subsequently, to the resulting mixture is added, preferably in order, a solution comprising 3 g of lactic acid (80%) in 65 g of distilled water, 20 g of urea, 15 g of sunflower oil and 20g Neodol 91 "6 and / or Tergitol NP-9. The resulting mixture is stirred for 15 minutes at a temperature of about 80 ⁰ C to about 85 ° C. The resulting mixture is cooled to room temperature. About 300 g of a liquid composition is obtained in the form of oil microemulsion in transparent and stable water.

The composition of Example 18 comprises about 5% by weight of microemulsion free sunflower oil, about 6.6% by weight of urea and about 48% by weight of water.

Examples 2 to 18 illustrate liquid compositions, in the form of oil-in-water microemulsions, preferred of the present invention for treating alopecia. Said compositions are particularly effective in inducing and stimulating the growth of hair and curbing their fall and that they can be used, in particular, for cleaning and conditioning hair.

The compositions of Examples 2 to 18 are useful for inducing and stimulating hair growth and curbing hair loss and can be used, in particular, for cleaning and conditioning hair.

Increasing the level of urea for a given formulation results in an increase in its viscosity. According to the present invention, microemulsions in gel form have been obtained by controlling the amount of water and the level of urea. At least about 10% by weight of urea, for amounts of water ranging from about 20% to about 45% by weight, are required to prepare a gel suitably thickened. Urea is likely to force the hexagonal phase surfactant system.

Detergent gels including urea and surfactants are known in the art. U.S. Patent No. 4,165,819 issued to Leng et al., October 7, 1986, discloses detergent gel compositions in the form of hexagonal liquid crystals which consist of certain anionic or cationic surfactants in combination with certain additives such as urea (incorporated patent). to the present invention for reference).

Example 19: microemulsion type oil in water in the form of gel In a container provided with magnetic stirring, OE introduces 25 g of sunflower oil, 40 g of coconut oil and 25 g of Tergitol NP-9 which is door at a temperature of about 80 ⁰ C to about 85 ⁰ C using a water bath. Then, a solution comprising 10.6 g of sodium hydroxide, 1.6 g of sodium chloride, 0.4 g of EDT A-Na ₂ and 77 g of distilled water is added to this mixture. The resulting mixture is stirred at a temperature of about 80 ⁰ C to about 85 ⁰ C for 15 minutes. Subsequently, to the resulting mixture is added, preferably in order, a solution comprising 3 g of lactic acid (80%) in 25 g of distilled water, 60 g of urea, 15 g of sunflower oil and 20g of Tergitol NP-9. The resulting mixture is stirred for 15 minutes at a temperature of about 80 ⁰ C to about 85 ⁰ C. The mixture obtained (about 300 g) is a fluid mixture at 60 ⁰ C and is cooled to give a microemulsion oil in the water in the form of transparent and stable gel, aesthetically pleasing. The gel is easy to work and condition and its viscosity can be easily adjusted.

The composition of Example 19 comprises about 5% of microemulsion sunflower oil. Table S: Example 19: Composition of microemulsion in gel form

Component Percentage by weight

Free sunflower oil 5

Free fatty acids * 2.42

Glycerin ** 2.23

Glycerides *** 1.22

Mixture of sodium salts of fatty acids **** 18,48

Tergitol NP-9 15 urea 20

Sodium lactate 0.96

Sodium chloride 0.53

EDTA-Na ₂ 0.13

Water 34.03

* Fatty acid mixture comprises about 30.86% stearic acid and 69.14% oleic acid.

** Amount of glycerine formed in situ during the hydrolysis of the oils of the composition.

*** Mixtures of mono- and / or di-glycerides.

**** Blend of coconut oil / sunflower oil mixed sodium salts in a 65:35 weight ratio and has an approximate carbon chain length distribution of 5.9% C ₈ , 5.1% Ci ₀ , 36.2% Ci ₂ , 13.0% Cu, 8.6% Ci ₆ ,

2.6% sodium oleate, 28.1% sodium linoleate.

In the aforementioned Leng et al. Patent, when urea is used as an additive in detergent compositions, it is preferable to add a quantity of boric acid to trap aminoniac which results from the decomposition of urea during time. However, boric acid generally reduces the viscosity of the gels. The hydrolysis of urea to ammonia over time generally results in a degradation of the detergent properties of the composition which becomes uncomfortable to use. In the present invention, urea has been incorporated under such conditions that its stability is ensured by the presence of fatty acids. Indeed, urea forms stable complexes with fatty acids. The first description of the formation of stable fatty acid complexes with urea was indeed already established by Bengen in 1940 (German Patent OZ 12438 IS March 1940). For a long time, this technique has been used to purify fatty acids from vegetable fats and oils, for example, US Patent Number 4792418.

The detergent compositions of the present invention may contain thickening or suspending agents to provide even higher viscosities. Preferred thickeners include cellulosic polymers and oligomers substituted in varying degrees by different groups, gums such as guar gum and gum tragacanth and polymers. If a thickener is added to the composition, it will preferably be used in an amount of from about 0.01% to about 5% by weight of the composition.

Advantageously, the pH of the composition of the present invention is chosen in the range from 5 to 10 and preferably from 7 to 8.5, as measured in a 1% aqueous solution, at 25 ° C.

Another advantage of the compositions of the present invention is that they can contain a large amount of oil, without requiring the use of alcohols and solvents, which are usually undesirable for aesthetic reasons (odor) and for reasons of of toxicity.

The microemulsions of the present invention are characterized by their excellent stimulating properties of hair growth. Said microemulsions are quite fluid, more practical, easier to apply and more nice to use. The compositions obtained according to the invention have the advantage of spreading easily and being absorbed rapidly by the skin and the scalp.

The compositions of the examples of the present invention are useful for inducing and stimulating the growth of hair and curbing their fall and that they can be used, in particular, for cleaning and conditioning keratin materials such as skin and hair.

The compositions according to the present invention contain vegetable oils and urea which are thus important substances of skin care. Indeed, urea can hydrate the epidemic in depth; while vegetable oils maintain an oily layer on the surface of the skin and thus form a screen that prevents dermal water from evaporating. The oil evaporates at a much lower speed than the evaporation of water.

In order to evaluate the activity of the compositions according to the present invention, a study was carried out on male subjects having a state of hair lightening due to androgenic alopecia of a degree I to VII according to the Norwood-Hamilton classification. . Twenty-five men aged 23 to 45 were followed for 24 weeks. They were treated either with placebo or with a composition according to the invention for topical application at a rate of once to two per day. The composition according to the present invention is used in local application on dry or wet scalp, preferably dry. The placebo used for this study, is a mild shampoo for children available on the market. For extensive alopecia, a composition of the present invention is used twice a day morning and evening, in application local on dry scalp. Depending on the level of alopecia, one to two applications a day are recommended.

The method of cosmetic treatment of alopecia, according to the present invention, is characterized in that an effective amount of a composition as defined above is applied to the alopecic areas of the scalp, on the basis of one to two applications per day for 1 to 7 days per week and this for a period of 1 to 6 months. The application is eventually accompanied by a massage to promote penetration; then, the scalp thus treated is rinsed with water after possibly a pause of 1 to 30 minutes, preferably from 20 minutes to one hour, more preferably from 6 to 10 hours.

By the term "effective amount" is meant a sufficient amount of a composition of the invention to benefit a body part of the benefits of vegetable oils and free fatty acids, when the composition is applied locally.

The effective amount of a composition of the present invention has been estimated based on the results of some research (Ananthapadmanablian et al., Dermatology Therapy, 2004, 17, 16-25) which have addressed the problem of absorption of triglycerides and fatty acids through the skin. Indeed, in vivo studies (Ananthapadmanabhan et al., Dermatology Therapy, 2004, 17, 16-25) have shown that about 10-15 μg cm triglycerides are deposited on the skin during washing with a composition that contains 20% triglycerides. The same reference mentions that the use of sweet soap syndet, containing in its composition of free fatty acids, deposits on the skin approximately 12 μg per cm ² of fatty acids during the washing.

Effective amounts of a composition according to the invention that can be applied to the scalp to stimulate hair regrowth in the case subjects suffering from alopecia or for the conditioning of keratin materials, are about 50 mg / cm ² , without this indication being a limitation.

The most objective method, to follow the evolution of the alopecic zones, is the taking of comparative photographs before treatment then during the treatment. The evolution was demonstrated by photographs of all the alopecic areas, with the taking of new pictures every two weeks. The photographs are good witnesses of the evolution of the treatment. It is remarkable to mention that the hairs of the down, although visible to the naked eye, were not discernible in the photos. Thus, all quantitative and qualitative evaluations were made from terminal hairs.

After two weeks, the men of the group treated with a composition according to the invention presented a stop of hair loss. In men using placebo, hair loss has progressed.

In men treated with a composition according to the present invention, preferably compositions which contain microemulsion sunflower oil. more preferably the composition of Example 18, the growth of a new down and the strengthening of existing hair appears after 1 to 2 months of treatment. When the treatment is continued, the hair thickens and becomes darker, until it takes the color and structure of the hair already present. In addition, the hairs of the down become terminal hairs. The advanced cases of baldness respond as well to the treatment with the compositions according to the present invention, as well as those existing for more than ten years. These results show that microemulsions in accordance with the present invention are very useful for treating alopecia. No scalp irritation or allergy was reported during treatment with the compositions of the present invention. The compositions according to the invention, preferably the compositions which contain the microemulsion sunflower oil, more preferably the composition of Example 18, are likely to eliminate problems of sparse hair and baldness. The compositions according to the invention stimulate hair growth and reduce the lightening state of the scalp. This activity seems to be related on the one hand to the fatty acids contained in these compositions, but also to the phytosterols and tocopherols contained in the vegetable oils.

It is likely that the effectiveness of the compositions according to the invention in the treatment of alopecia, is the resultant of several mechanisms of action, the main one is the regulation of excess 5-alphareductase. Indeed, it is demonstrated that several components of the formula according to the present invention, have a 5-alphareductase inhibitory activity, for example, fatty acids, phytosterols and tocopherols. In addition, the microemulsion form improves the bioavailability of phytosterols and tocopherols at the cellular level. The effectiveness of said ingredients is therefore increased in comparison with non-microemulsified forms. The compositions of the present invention include dermal absorption promoters such as oleic acid and urea (Waker and Smith, Advanced Drug Delivery Reviews, 1996, 18, 295-301).

The present invention exploits certain advantages of microemulsions for treating hair loss problems. Indeed, improving the bioavailability of the ingredients is the major advantage and therefore the key factor in the use of the compositions according to the present invention in the treatment of alopecia. Washing and eoaditioBinβmemt keratin materials

The compositions of the present invention are useful for washing and conditioning keratin materials such as skin and hair. The method for washing and cosmetically conditioning keratinous materials consists in applying an effective amount of a composition, as described above, to the wet keratin materials, and the foam generated by massage or friction with the hands is then eliminated by rinsing with water after a possible pause time.

A shampoo cleans the hair by removing soiling and sebum. Cleansing also results in a loss of substances that are responsible for maintaining healthy hair and hair such as natural oils and other moisturizing substances; leading after washing to dryness, irritation, and even itching (Ananthapadmanabhan et al., Dermatology Therapy, 2004, 17, 16-25).

Indeed, surfactants, ubiquitous in shampoos and personal hygiene products, can damage the membrane of the stratum corneum and the cuticle which are respectively the outer layers of the skin and the hair. The destruction of the protective membranes of the skin and the hair leads to an irritation and a loss of the functions of the protective barrier of the skin.

The ideal shampoo compositions should provide sufficient foaming and washing benefits for washing the hair by causing little or no irritation of the hair. To achieve these goals, many conditioning materials have been proposed in the art, including hydrocarbon liquids, fatty alcohols, silicones, cationic surfactants, and cationic polymers. However, these solutions have not been entirely satisfactory because the cleaning components are in general incompatible with packaging materials, especially anionic surfactants with cationic agents and silicones.

The combination of vegetable oils and fatty acids according to the invention may be advantageously employed in place of those many conditioning materials which have been described in the art. Indeed, the use of the compositions according to the present invention in place of commercially available shampoos, was characterized by a positive effect on the softness of the hair.

The present invention provides; useful compositions for simultaneously cleaning and conditioning keratmic materials such as hair and skin. The compositions according to the invention include beneficial agents such as glycerol, urea, vegetable oils and fatty acids to improve skin hydration.

The present invention is particularly useful since it makes it possible to formulate compositions containing microemulsion oils for conditioning, while maintaining optimum cleaning performance. These new compositions make it possible to deposit a greater amount of oil on the hair than with the conventional compositions, but without affecting the bold visual appearance.

According to the present invention, the shampoo compositions comprise vegetable oils and free fatty acids of 18 carbon atoms. These act both to nourish and protect the hair. The compositions according to the invention additionally provide hair with cosmetic virtues: shine, swelling, ease of styling ... Finally, it is a "care shampoo", since in addition to washing, it nourishes the hair thanks to the different assets it contains. Although conventional detergents, such as soap and shower gel, are very effective in removing dirt and grease from the surface of the skin, they do not reduce sebum production by the sebaceous glands. Moreover, after a relatively short time, the level of sebum is restored.

Sebum is a complex mixture of triglycerides (57%), waxes (26%), squalene (12%), sterol esters (3%) and free sterols (2%). Sebum is produced in the sebaceous glands and secreted on the surface of the skin, from where it is removed by washing.

When the sebaceous glands produce more sebum, it accumulates in the follicle and clogs the pores; the skin becomes oily. This phenomenon is common and it is important to have good hygiene of oily skin. Good hygiene of oily skin consists of deep cleansing of the skin. For this purpose, microemulsions are an excellent means for deep pore cleansing due to increased capillary effects and micro-emulsification of sebum.

WO 2005/020939 (Unilever) discloses a process for microemulsification of sebum by contact using block copolymers.

Due to the spontaneous microemulsification of the triglycerides according to the present invention, the compositions described, particularly phase A of the composition of Example 17, can form microemulsions by contact with the sebum and allow deep cleaning of the skin.

In fact, in products for personal hygiene, there is a direct relationship between quality and efficiency: the better the quality, the greater the effectiveness. Quality is more affected by the nature of the ingredients; a good product 07 0000H

quality must contain fewer synthetic ingredients. The compositions according to the present invention contain more ingredients of vegetable origins.

Indeed, the compositions of the present invention include sodium laurate as the main anionic surfactant. Sodium laureth sulfate (SLES) and sodium lauryl sulphate (SLS) are ubiquitous in commercially available personal care products. Some studies (Imokawa, Surfactants in Cosmetics, Surfactant Science Series, 1997, 427-47Ij have demonstrated that SLS has the same effects on skin as sodium laurate.) Others (Υan der VaIk et al., J Invest Dermatol ., 1984, 82, 291-293, on the other hand, have tried to demonstrate the opposite, ie, that sodium laurate is milder than SLS.

According to these different studies, that sodium laurate has the same effects on the skin as the SLS; or it has lesser effects.

However, the idea that sodium laurate has negligible effects compared to SLS ₃ has been supported by some studies. The first of these studies showed that a 50% solution of a coconut oil soap, of which sodium laurate is the main compound, was tested on human skin. After 4 hours of exposure, skin irritation was judged to be negligible (Nixon et al., Toxicol Appl., Pharmacol 1975, 31, 481-490).

The second is the work of HERA; which is a European body responsible for assessing the impact of detergents on human health and the environment. This organization states that the use of cleaning products containing fatty acid salts does not raise concerns directly related to human health (HERA Targeted Risk Assessment of Fatty Acids Salts, June 2002). While SLS _{5 is} a health-damaging compound, it causes changes in the body's proteins, hair loss and skin dryness (Rhein et al., J. Soc Cosmet Chem., 1986, 37, 125- 139). Its replacement with sodium laureth sulfate (SLES) does not definitely solve the problem of irritation of the skin. The latter may cause more serious damage to human health in that it contains dioxane as an impurity; which is a carcinogen (Stickney et al., Reg Toxicol Pharmacol, 2003, 38, 183-195).

As far as rinsing is concerned, it is important to know that this is an important, if not essential, element of a cleaning product. However, the ordinary soap in contact with the tap water forms foam which is deposited in film on the skin and hair, making it difficult to rinse. As mentioned above, the nonionic surfactant inhibits scum growth by suitably dispersing the calcium and magnesium salts of the fatty acids in the bath water (Αntonenko et al., Colloid Journal, 2002). It is readily understood that rinsing, shower gels, and shampoos according to the present invention are easy and quick, and after use it has actually been found that the rinsing of the compositions according to the present invention is more easy and does not require a lot of water.

In comparison with commercially available shower gels and shampoos that contain SLS or SLES, during rinsing, a large amount of water is required to get rid of any foaming trace: rinsing is therefore long. In fact, it's not like soaps, SLS and SLES do not form insoluble compounds with calcium ions from tap water. To improve the rinsing, these two surfactants were combined with polyammoniums or calcium ions (1-5%). This will compromise the effectiveness of cleaning. MA2007 / 000011

On the other hand, cocoamide DEA, present in commercially available shampoos, has the main function of improving the stability of the bubble structure and providing a thick and creamy texture. Indeed, the bubbles will become fine after being coarse. According to the present invention, the presence of free fatty acids can have these same effects, as is the case in shaving creams. In addition, in the presence of nitrites, cocoamide DEA forms potentially carcinogenic nitrosamines (Proksch, Int.J.Hyg.En.Health, 2001, 204, 103-110). Nitrites are often present in raw materials used in body care products.

The compositions according to the present invention are endowed with many virtues. They moisturize and smooth skin and hair and meet the demands of modern life. They have been designed according to the sanitary standards required as the ingredients used are beneficial to the skin and hair and prevent drying out.

The oil-in-water microemulsion compositions of the present invention are stable and economical, are unheard of expensive and perform better than conventional formulations.

The droplet size of microemulsions seems to be a major asset for the stability offered to the microemulsion but also increases the bioavailability of lipophilic ingredients. Their effectiveness in improving the bioavailability of the ingredients is the major advantage and therefore the key factor in their use in the treatment of alopecia according to the present invention.

Ingredients used in the present invention: Sodium hydroxide pellets for analysis (Sigma), sodium chloride for analysis (Polysciences, INC), disodium EDTA for analysis (Acros), lactic acid 80% (Brenntag Morocco), sunflower oil ( Aisha). argan oil (Tissaliwine), p-toluenesulfonic acid (Prolabo monohydrate).

Claims

claims

A detergent composition for treating alopecia, reducing hair loss and increasing hair density, characterized in that it is in the form of a transparent and stable oil-like microeπralsion in the body. water comprising: a) from about 0.01% to about 20% by weight of at least one oil of microemulsion vegetable or animal origin, said oil containing long chain fatty acid triglycerides; b) from about 1% to about 40% by weight of fatty acid salts; c) from about 1% to about 30% by weight of at least one nonionic surfactant; d) 0% to about 15% by weight of free fatty acids in

e) from about 10% to about 95% by weight of water; f) from about 0.1 to about 10% by weight of a moistening agent; g) from about 0.1% to about 10% by weight of an electrolyte; and h) 0% to about 30% of a water-soluble additive selected from the group consisting of lower amides having not more than 6 aliphatic carbon atoms and mixtures thereof.

2. A microemulsion detergent composition for treating alopecia, according to claim 1, characterized in that it is in liquid or gel form.

3. A microemulsion detergent composition for treating alopecia, according to claim 1, characterized in that it comprises from 10% to 95% water, preferably from 20% to 70%, more preferably 25% 60% by weight of the total composition.

4. A microemulsion detergent composition for treating alopecia, according to claim 1, characterized in that said microemulsion oil has an iodine number greater than 50, more preferably greater than 90, more preferably still greater than at 130, and most preferably above 150.

5. A microemulsion detergent composition for treating alopecia, according to claims 1 or 4, characterized in that the vegetable oil is preferably chosen from linseed oil, argan oil, oil and of wheat germ, olive oil, sunflower oil, soybean oil, corn oil, borage oil, avocado oil, evening primrose oil or their mixtures.

6. A microemulsion detergent composition for treating alopecia according to claim 1, characterized in that the amount of the microemulsified oil is from 0.01% to 20%, the weight of the microemulsion, preferably from 2% to 10%, more preferably 4% to 7%.

7. A microemulsion detergent composition for treating alopecia, according to claim 1, characterized in that said fatty acid salts are straight or branched chain, saturated or unsaturated, natural or synthetic or mixtures thereof.

8. A microemulsion detergent composition for treating alopecia, according to claim 7, characterized in that said branched-chain fatty acid salts are secondary monocarboxylates of formula R ¹ CH (R ² ) COOM, in which R ¹ and R ² are alkyl or alkenyl groups and the sum of the carbon atoms in R ¹ and R ² is 8 to 16.

A detergent composition in the form of a microemulsion for treating alopecia, according to claim 7, characterized in that said salts of fatty acids with branched chain are tertiary C10-C18 carboxylates of formula

R ³ CR ⁴ (R ⁵ ) COOM, wherein the sum of the carbon atoms in R ³ , R ⁴ and R ⁵ is 8 to 16.

A microemulsion detergent composition for treating alopecia, according to claim 7, characterized in that said straight chain fatty acid salts are Cs-C ₂₄ fatty acid salts, preferably acidic salts thereof. containing 8 to 22 carbon atoms, more preferably 8 to 18 carbon atoms,

A detergent composition in microemulsion form for treating alopecia, according to claims 10, characterized in that said mixture of fatty acid salts preferably comprises a coconut oil fatty acid salt and / or a fatty acid salt of palm kernel oil and / or an acid salt of babassu oil and a fatty acid salt of an oil as defined in claim 4.

A microemulsion detergent composition for treating alopecia, according to claim 7, characterized in that said fatty acid salts include alkaline salts such as sodium, potassium and / or lithium salts as well as ammonium and / or alkylammonium salts of fatty acids, preferably the sodium salt.

13. Detergent composition in the form of a microemulsion for treating alopecia, according to the preceding claim, characterized in that said fatty acid salts can be produced by direct saponification of fatty substances and / or oil or by the neutralization of free fatty acids with the appropriate alkali or. alkylamines or alkanolamines. 2007/000011

14. A detergent composition in the form of a microenhansion for treating alopecia, according to claim 13, characterized in that said fatty acid salts are produced by direct saponification in the inicellar phase which consists of reacting together at a temperature of about 40 ⁰ C at about 90 ⁰ C, an oil phase comprising at least one vegetable oil, an aqueous phase comprising an alkali and an electrolyte and in the presence of at least one nonionic surfactant.

A detergent composition in microemulsion form for treating alopecia, according to claim 14, characterized in that said fatty acid salts comprise about 3% to 30% by weight of coconut oil fatty acid sodium salts. and / or palm kernel oil and / or babassu oil, and about 0.1% to 20% by weight of fatty acid sodium salts of a long chain oil; said fatty acid salts contain about 90% by weight of fatty acid salts having carbon chain lengths in the range of C ₁₂ to Qg.

16. A detergent composition in microemulsion form for treating alopecia, according to claims 1 or 14, characterized in that the nonionic surfactant is selected from the group consisting of alkylphenols or fatty alcohols alkoxylated, preferably alkoxylated with the oxide ethylene or mixtures of ethylene oxide and propylene oxide; polyglycol esters of fatty acids or fatty acid amides; ethylene oxide / propylene oxide block polymers; glycerol esters such as monoglycerides, esters of glycerol polyesters; sorbitol and sorbitan esters, sucrose esters, water-soluble amine oxides, water-soluble phosphine oxides, water-soluble sulfoxides, and mixtures thereof.

17. A microemulsion detergent composition for treating alopecia, according to claim 16, characterized in that the nonionic surfactant is an ethoxylated nonionic surfactant comprising a C ₆ -C ₂₂ alkyl chain or a C 7 alkylbenzene chain. ₆ to C ₂ S and with an average degree of ethoxylation of 0 to 2O ₅ preferably 1 to 15, more preferably from 5 to 12, and, which is much better, of 6 to 10.

A microemulsion detergent composition for treating alopecia, according to claims 17, characterized in that the amount of nonionic surfactants is from about 2% to about 40%, by weight of the microemulsion, preferably from about 5% to about 40%, more preferably about 8% to about 20%.

19. A detergent composition in microemulsion form to treat hair loss according to claim I ₅ characterized in that said fatty acids are fatty acids with straight or branched chain, saturated or unsaturated having a length ranging from C ₁ 2 to ₂₂ € preferably, fatty acids of 18 carbon atoms such as stearic acid, oleic acid, linoleic acid, linolenic acid or mixtures thereof.

20. A microemulsion detergent composition for treating alopecia, according to claim 19, characterized in that said free fatty acids can be produced with an in situ reaction of an acidic compound with a half of the formed fatty acid salts. in the saponification step; the acidic compound may be organic or inorganic, and preferably water-soluble with a pKa of about 6, more preferably a pKa of less than 5.

21. A microemulsion detergent composition for treating alopecia, according to claim 19, characterized in that it comprises 0% to about 10% of free fatty acids, preferably from about 2% to about 5% by weight of the composition.

22. A detergent composition in the form of an imroperulsion for treating alopecia, according to claim 1, characterized in that said composition contains from about 0.1 to 10% by weight of said electrolyte which is selected from sodium chloride, chloride potassium, ammonium chloride, sodium thiolactate, sodium thioglycolate, salts of alpha-hydroxy acids such as citrates, tartrates and lactates, salts of amino acids such as aspartates, salts of organic diacids, sodium sulphate, sodium salts of pysiapfahoric acid, short chain alkylbenzene sulphonate salts, and mixtures thereof.

23. A microemulsion detergent composition for treating alopecia, according to claim 1, characterized in that it comprises from about 0.1% to about 10% by weight of a moistening agent, preferably from 'about

From about 2% to about 6% by weight; said agent is selected from water-soluble polyols and essential amino acid compounds, preferably glycerol which is formed in situ in the saponification step as defined above.

24. A microemulsion detergent composition for treating alopecia, according to claim 1, characterized in that said water-soluble additive is urea.

25. A detergent composition in microemulsion form for treating alopecia, according to any one of claims 1 to 24, characterized in that it further comprises preservatives, antioxidants such as tocopherols and a chelating agent. selected from the group consisting of ethylenediaminetetraacetic acid and its derivatives and salts.

A composition according to any one of the preceding claims which further comprises another surfactant or a mixture thereof, said surfactant being selected from the group consisting of amphoteric surfactants, alkylbenzoic acid salts of which the group alkyl contains 5 to 10 carbon atoms, the anionic surfactants, the zwitterionic agents, the cationic surfactants and mixtures thereof and being incorporated at a level of from 0.1% to 20% by weight of the total composition, preferably from 0 to , 1% to 10% and more preferably 0.1% to 5%.

27. A detergent composition in the form of a microemulsion for treating alopecia, according to any one of the preceding claims, characterized in that it has a pH of between 5 and 10, preferably 7 to 9, and more preferably of 7 to 8.

28. Process for the cosmetic treatment of alopecia, characterized in that an effective amount of a composition as defined in any one of Claims 1 to 27 is applied to the alopecic areas of the scalp, on the basis of one to two applications per day for 1 to 7 days per week and this for a period of 1 to 6 months; the application may optionally be accompanied by a massage to promote penetration; then, the scalp thus treated is rinsed with water after possibly a pause of 1 to 30 minutes, preferably from 20 minutes to one hour, more preferably from 6 to 10 hours.

29. A method for treating alopecia, according to claim 28, characterized in that said alopecia is androgenic alopecia. MA2007 / 000011

30. Use of a composition as defined in any one of claims 1 to 27 for washing and / or conditioning keratin materials such as skin and hair.

31. A method of washing and / or conditioning keratinous materials comprising applying an effective amount of a composition according to any one of claims 1 to 27, to said wet materials, and then performing a rinsing with water after a possible break time.

32. Use of a composition as defined in any one of claims 1 to 27 as a shampoo for the prevention of hair loss.

33. A detergent composition in the form of a transparent and stable microemulsion, characterized in that it comprises: a) from about 0.01% to about 20% by weight of a microemulsified fat; b) from about 1% to about 40% by weight of fatty acid salts; c) from about 1% to about 30% by weight of at least one nonionic surfactant; d) 0% to about 15% by weight of free fatty acids C ₈ -C _22; e) from about 10% to about 95% by weight of water; f) from about 0.1% to about 10% by weight of a moistening agent; g) from about 0.1% to about 10% by weight of an electrolyte; and h) 0% to about 30% by weight of a water-soluble additive selected from the group consisting of lower amides having not more than 6 aliphatic carbon atoms and mixtures thereof.

34. Microemulsion detergent composition according to claim 33, characterized in that it is in liquid or gel form.

A detergent composition in the form of a microenulsion, according to claim 33, characterized in that said fat may be selected from the group consisting of vegetable oils, waxes, animal oils, mineral oils, synthetic oils, fatty acid esters such as isopropyl myristate, water insoluble silicones, polyol esters, ether polyol esters, sorbitan fatty esters, lanolin and lanolin derivatives, and mixtures thereof.

36. A detergent composition under a microemulsion foil according to claim

35, characterized in that the polyol esters may be of synthetic origin, or of vegetable or animal origin, or mixtures thereof.

37. Microemulsion detergent composition according to claim

36, characterized in that said esters comprise one or more fatty acid esters per polyol molecule and that the fatty acid chains of the polyesters are each independently a fatty acid group which may be the same or different.

38. Microemulsion detergent composition according to claim

37, characterized in that the carbon chain of said fatty acids contains from 1 to 30, preferably from 8 to 24 carbon atoms, linear or branched, saturated or unsaturated, interrupted or not by one or more heteroatoms.

39. A microemulsion detergent composition according to claim

38, characterized in that the fatty acids are selected from the group consisting of lauric acid, myristiatic acid, stearic acid, palmitic acid, palmoleic acid, oleic acid, linoleic acid. linolenic acid and mixtures thereof.

40. Microemulsion detergent composition according to claim

38, characterized in that the fatty acid is palmoleic acid, oleic acid, linoleic acid, linolenic acid or mixtures thereof.

41. A detergent composition in microemulsion form, according to claim 36, characterized in that said polyol is a diol, a triol or a tetraol.

42. Microemulsion detergent composition according to claim 41, characterized in that the polyol is chosen from ethylene glycol, propylene glycol, butylene glycol, glycerol, 1,3-dihydroxyacetone and mixtures thereof.

43. Detergent composition in microemulsion form. according to the claim

35, characterized in that the ether polyol contains at least one free hydroxyl group such as 1,2-isopropylidene glycerol.

44. Use of a composition, according to claims 33 to 43, for washing and / or conditioning keratin materials such as skin and hair.

45. Use of a composition as defined in any one of claims 33 to 43 for cleaning and / or conditioning the hair, for stimulating or inducing hair growth and for stopping the process of hair loss in the hair. 'To be human.

46. A process for the cosmetic treatment of keratin materials, comprising the application of an effective amount of a composition according to any one of claims 33 to 43, to said wet materials, to rinsing with water after a possible break time.

47. A cosmetic process for reducing or controlling the oily or oily appearance of the skin by applying to the skin a composition according to any one of claims 1 to 27 or 33 to 43, then to rinsing with water after a possible break time.

48. A cosmetic method of sebum microéniulsifîcation by applying to the skin a composition according to any one of claims 1 to 27 or 33 to 43, and then in rinsing with î ^water after an optional action time.

49. Microemulsion detergent composition according to claims 1 to 27 or 33 to 43, characterized in that the said composition is prepared by the following steps: the formation of a mixture (A) containing at least one nonionic surfactant and salts of fatty acids and / or fatty acid sources, examples of fatty acid salt sources include oils such as coconut oil and sunflower oil. In the second step, an aqueous phase is prepared which comprises distilled water, at least one electrolyte, a chelator and an alkali, preferably sodium hydroxide (to form the fatty acid salts when said sources are acids fatty and / or glycerol esters) and the other water-soluble ingredients that can be incorporated into the composition. The said aqueous phase is mixed, with stirring, with the said mixture (A) heated to a temperature of approximately 40 ^° C. to approximately 90 ^° C. After a time ranging from 5 to 60 minutes, preferably 15 minutes, it is added, under stirring, fatty acids and / or an aqueous solution of an acidic compound as defined in claim 20 to form in situ free fatty acids, urea, at least one surfactant and a fat, which will be microemulsified, as defined in claim 1 or claim 33, as well as optional ingredients.