The present invention relates to a composition which makes possible the release of a beneficial agent comprising at least one beneficial agent and a support comprising at least one water-insoluble cyclodextrin polycondensate, it being possible for said cyclodextrin polycondensate to be obtained by esterification/polycondensation reaction:

A) of at least one cyclodextrin and

B) of at least one saturated or unsaturated or aromatic, linear or branched or cyclic polycarboxylic acid and/or at least one ester or one acid anhydride or one acid halide of said polycarboxylic acid and

C) of at least one thermoplastic polyol polymer and

D) optionally of at least one esterification catalyst and/or

E) optionally of at least one cyclic anhydride of a polycarboxylic acid chosen to be other than the polycarboxylic acid anhydride of paragraph B) and/or

F) optionally of at least one non-polymeric polyol comprising from 3 to 6 hydroxyl groups.

Another subject-matter of the invention consists of a consumer product comprising at least one composition which makes possible the release of a beneficial agent as defined previously, in particular a cosmetic or dermatological composition comprising a physiologically acceptable medium.

In addition, the invention relates to a process for cosmetic treatment of a keratin material, consisting in applying, to the surface of said human keratin material, a consumer product comprising a composition as defined above containing, in a physiologically acceptable medium, at least one beneficial agent chosen from cosmetic active agents. The objective of the present invention is to search for new materials which make it possible to trap at least one beneficial agent and to delay its time for release to the exterior for the purpose of:

(i) protecting it, for example during its storage or during its transportation, in order to prevent it from deteriorating, for example under the influence of atmospheric agents such as heat or cold, variations in temperature, ambient moisture, atmospheric oxygen or UV radiation;

(ii) owing to its sensitive chemical or physical nature, isolating it and preventing or delaying its contact with one or more other ingredients of a composition or with the site on which it must be applied, with which it is incompatible;

(iii) or trapping it and prolonging the duration of its release out of the capturing material in order to improve its effectiveness and/or its wear property and/or its deposition on the area where it must be applied. Among the beneficial agents used in particular in the cosmetics or pharmaceutical industry, in perfumery, in the food-processing industry or in products resulting from the textile or leather industry, in particular in textile materials or else in cleaning products, mention may more particularly be made of fragrances, fragranced essences, essential oils, bleaching agents, insecticides, colorants, lipids, silicones, waxes, flavourings, enzymes, oxidizing agents, microorganisms, phytosanitary active agents, food additives such as flavour enhancers, textile softeners, antibacterials, cooling agents, active ingredients of medicaments, and cosmetic or dermatological active agents. Such beneficial agents are generally expensive and/or volatile and/or physicochemically unstable and/or effective over periods of time which are too short. There is therefore a need to optimize their amount in order to limit costs, to improve their stability, to protect them against their environment and/or to improve their effectiveness over time. One of the means known from the prior art for achieving these objectives is the microencapsulation of these substances. In addition to the advantages previously mentioned, this encapsulation can also make it possible to render the material easier to use by diluting it and by promoting its homogeneous distribution within the support.

Microencapsulation groups together all the technologies for coating or trapping substances in solid, liquid or gas form within individualized particles, the size of which ranges between a few microns and a few millimetres. If these microparticles are hollow (vesicular) they are referred to as microcapsules, and if they are solid (matricial) they are referred to as microspheres. Their size ranges from 1 m to more than 1000 pm. These microparticles can be biodegradable or non-biodegradable and can contain between 5% and 90% (by weight) of encapsulated substance.

The encapsulated substances are very varied in origin: pharmaceutical active ingredients, cosmetic active ingredients, food additives, phytosanitary products, fragranced essences, microorganisms, cells, or else chemical reaction catalysts, etc.

The entire advantage of these known microcapsules lies in the presence of a polymeric membrane, which isolates and protects the content from the external environment. As required, the membrane will be destroyed during use for the release of its content (for example: "scratch and sniff" advertising inserts which release the fragrance when the microcapsules are crushed), or else the membrane will remain present throughout the release of the content, the rate of diffusion of which it will control (example: encapsulation of medicaments for slow release). The main methods of the prior art for carrying out the encapsulation of substances in microparticles are interfacial polymerization, interfacial crosslinking, emulsion followed by solvent evaporation or extraction, double emulsion solvent evaporation/extraction, spray drying, prilling, coacervation, etc. Microbeads consisting of hydrophobic polymeric materials which are generally prepared by phase separation techniques (coacervation or solvent extraction-evaporation) or by polymerization or polycondensation are also known. The phase separation techniques generally use organic solvents which have a certain number of drawbacks: elimination into the atmosphere, persistence within galenical systems, denaturation of certain microencapsulated molecules. The methods by polymerization or polycondensation that are known to date have the drawback of using highly reactive materials capable of reacting with the substances encapsulated within the microbeads.

Microbeads formed from hydrophilic polymeric materials which are generally prepared by gelling or coacervation techniques are also known from the prior art. This technique which makes it possible to encapsulate molecules in liquid or solid form is based on the desolvation of macromolecules, resulting in phase separation within a solution.

As regards encapsulation in lipid materials, the technique of microencapsulation by thermal gelling is known. This process, known as hot melt, is based on melting the coating material. The substance to be encapsulated is dissolved or dispersed in this molten material. The mixture is emulsified in a dispersing phase, the temperature of which is kept above the melting point of the coating. The solidification of the dispersed globules is obtained by abruptly cooling the medium. Alongside this type of particulate microencapsulation, molecular encapsulation (cyclodextrins) is also known. The latter constitutes an advantageous alternative to the conventional encapsulations described above. Cyclodextrins have in fact been increasingly used for this purpose since the 1980s since they are cage molecules which can selectively and reversibly complex a large diversity of organic molecules in the form of "host-guest" inclusion complexes. Cyclodextrin inclusion complexes are particularly useful for transporting, protecting and releasing chemically and thermally sensitive ingredients. The release of the complexed ingredients is generally brought about via water or temperature.

Cyclodextrins are a family of natural cyclic oligosaccharides obtained by enzymatic degradation of starch. They consist of alpha-D-glucose units (6 to 12 units) linked to one another so as to form rings delimiting in their centre a frustum-shaped cavity.

The most abundant are the hexamers (a-cyclodextrin), heptamers (β-cyclodextrin) and octamers (γ-cyclodextrin) which differ in terms of the number of glucose units and consequently in terms of the size of the conical cyclic cavity which results therefrom. All the hydroxyl (OH) polar groups are located on the exterior, making the exterior hydrophilic and explaining their solubility in water. Since the interior of the cavity contains only the glycosidic oxygen atoms and the hydrogen atoms directly bonded to the carbons, said cavity is hydrophobic and considerably less polar. This amphiphilic nature enables cyclodextrins to include in their cavity lipophilic (hydrophobic) molecules, provided that the size and the geometric shape of the molecules lend themselves thereto, so as to form inclusion complexes which are generally water- soluble. Their non-toxic and biodegradable nature predisposes them to important applications in the food-processing and pharmaceutical fields. The encapsulation in cyclodextrins in fact makes it possible to protect fragile molecules or to provide the slow and controlled release thereof. Furthermore, the solubilization of water-insoluble medicaments in the form of inclusion complexes in cyclodextrins makes it possible to have injectable preparations.

Native cyclodextrins can be chemically modified, for example to give ethers or esters, which will modify the solubility both of the modified cyclodextrins and of the inclusion complexes. Many advantages follow from this and allow cyclodextrins to be widely used in various industrial fields.

Cyclodextrins are also commonly used as a formulation excipient in medicaments. They make it possible in particular to convert liquid compounds into solids (powders, tablets) by inclusion complex precipitation. The complexation of the active ingredients makes it possible to have better control of their passage into the bloodstream or the progressivity of their diffusion. Another application is sublingual treatment. The complexation of photosensitive or highly reactive active ingredients often makes it possible to protect them or to stabilize them.

The food-processing industry also commonly uses cyclodextrins as taste enhancers, allowing easy addition of taste compounds, or for fixing molecules that are too volatile and prolonging, for example, the taste duration of chewing gums. They are also used, on the contrary, for removing certain undesirable molecules, in particular for reducing the levels of cholesterol or of bitter compounds of ready meals or else as masking agents against bad odours. Cyclodextrins are also used for stabilizing emulsions such as mayonnaise or margarines.

In the cosmetics industry, they also make it possible to stabilize emulsions and odorous or active molecules.

In the textile industry, they are used for attaching active compounds (fragrances, antibacterials) to fabric.

However, the cyclodextrins commonly used have drawbacks.

From a geometric point of view, the inclusion will depend on the relative size of the cavity of the cyclodextrin relative to the size of the guest molecule; if said molecule is too large, it will not be able to penetrate inside the cavity of the cyclodextrin and if, on the other hand, its size is too small, it will have few interactions with the cyclodextrin. The steric effect therefore plays an important role in the complexation phenomenon.

Furthermore, the cyclodextrin:guest molecule molar ratio of the inclusion complexes is generally 1:1 or higher; in other words, at most one molecule is transported per cyclodextrin molecule.

Finally, the chemical nature of the compounds which can form stable inclusion complexes with cyclodextrins is restricted to lipophilic (hydrophobic) compounds since they must displace the water molecules present in the cavity. The relatively low water-solubility of cyclodextrins, in particular of the commercial cyclodextrins, and in particular of the one which is most economically accessible, β-cyclodextrin (18 g/l, i.e. 15 mmol/l, at 25°C), can constitute a limit in their use. In order to remedy this situation, chemically modified cyclodextrins have been proposed in the prior art. For example, primary alcohols have been substituted with monosaccharide or oligosaccharide groups, on the one hand so as to improve their water-solubility and, on the other hand, so as to incorporate cell recognition signals into their structure (international applications PCT WO 95/19994, WO 95/21870 and WO 97/33919).

However, the cyclodextrin derivatives of the prior art can have certain limitations, in particular with respect to the substances that may be transported, to the substance load capacity per unit weight of the cyclodextrin derivative, to their capacity to complex certain families of molecules, in particular hydrophilic molecules, to their cost, to their toxicity, and to the ease with which they can be synthesized.

Also known in the prior art are cyclodextrin polymers which have polymer- substrate complex stability constants that are often higher than those of native cyclodextrin-substrate complexes, and for which the hydrophobic and hydrophilic compounds and the supramolecules are more readily complexed and less readily released by the cyclodextrin polymers than by the native cyclodextrins.

Various types of cyclodextrin polymers and various preparation methods are thus known in the prior art (see, for example, Comprehensive Supramolecular Chemistry vol. 3, J.L. Atwood et al., Eds Pergamon Press (1996)).

These cyclodextrin polymers can be categorized into two types depending on whether the cyclodextrin constitutes the backbone of the polymer or else is a side substituent of a polymer chain.

The methods for synthesizing these prior art cyclodextrin polymers, the cyclodextrin of which constitutes the backbone, are based on the use of generally bifunctional crosslinking agents, such as epichlorohydrin, dialdehydes, diacids, diesters, diisocyanates, dihalogenated derivatives, polyisocyanates, bis-epoxides, acid dihalides in an organic solvent or else phytic acid.

A process for producing copolymers of cyclodextrin(s) using epichlorohydrin was proposed by Solms and Egi (Helv. Chim. Acta 48, 1225 (1965); US 3 420 788). Likewise, several modifications of the method of crosslinking with epichlorohydrin were later proposed in documents Wiedenhof N. et al., Die Starke 21(5), 119-123 (1989), Hoffman J.L., J. Macromol. Sci.-Chem, A7(5), 1147-1157 (1973), JP58171404 and JP61283601.

A process using a bifunctional agent, such as a dialdehyde, a diacid, a diester, an acid dichloride, a diepoxide, a diisocyanate or a dihalogenated derivative has been described in document US 3 472 835. This method envisages the activation of cyclodextrins via the action of sodium metal in liquid aqueous ammonia and then reaction with the bifunctional crosslinking agent.

A process using polyisocyanates in aprotic organic solvents has been described in documents US 4 917 956, Asanuma H. et al. Chem. Commun, 1971-1972 (1997) and W09822197. A process using ethylene glycol bis(epoxypropyl)ether has been described by Fenyvesi E. et al. in document Ann. Univ. Sci. Budapest, Rolando Eotvos Nominatae, Sect. Chim. 15, 13-22 (1979). A process using other diepoxy compounds has also been described by Sugiura I. et al. in document Bull. Chem. Soc. Jpn., (62, 1643-1651 (1989)).

A process using dicarboxylic acid dihalides in an organic solvent has been developed in documents US 4958015 and US 4902788.

A process based on phytic acid (which is a polyphosphoric acid) used for crosslinking cyclodextrin via a heat treatment under vacuum has been described in document US 5734 031. The main drawback of the processes for crosslinking cyclodextrins with epichlorohydrin is the corrosive and toxic properties of this reagent. The processes based on the use of diepoxy compounds prove to be toxic and to have a high cost price. Crosslinkings with polyisocyanates and diacid dihalides require the use of organic solvents which are harmful to the environment and cannot therefore be used on a large scale.

The second type of polymer is that in which the cyclodextrin is a pendent group of a polymer chain; it is produced by grafting cyclodextrin(s) or cyclodextrin derivative(s) onto a pre-existing polymer chain.

Thus, DE19520989 describes the grafting of cyclodextrins onto cellulose polymers via halotriazine and halopyrimidine derivatives. Furthermore, cyclodextrins have also been functionalized with aldehyde groups and then grafted onto chitosan via a reductive amination reaction; such a reaction is described by Tomoya T. et al. in J. Polym. Sci., Part A: Polym. Chem. 36 (11), 1965-1968 (1998). These cyclodextrin-based polymers can also be synthesized by functionalization of said cyclodextrin with polymerizable functional groups such as acryloyl or methacryloyl. This functionalization is followed by polymerization or copolymerization of these derivatives. Such processes have been described in document DE4009825, by Wimmer T. et al. in Minutes Int. Symp. Cyclodextrins 6th 106-109, (1992) Ed. Hedges A.R. Ed. Sante Paris, and by Harada A. et al. in Macromolecules 9(5), 701-704 (1976).

Finally, a process using acrylates, acrylic acid and styrene with insolubilization of the cyclodextrin has been carried out by emulsion polymerization in document EP780401.

In order to obtain cyclodextrin polymers under conditions which are non- polluting, non-toxic and less expensive than those of the processes mentioned above, Martel et al. have described, in the patent EP1165621B1, the synthesis of polymers from a solid mixture of cyclodextrin, of polycarboxylic acid or polycarboxylic acid anhydride and of a crosslinking catalyst, at a temperature of 100 to 200°C without the use of organic solvent. The mechanical properties and the molecular weight of these polymers are not controllable, with low stability and a low molecular weight. The work by B. Martel et al. (Journal of Applied Polymer Science, Vol. 97, 433-442 (2005)) describes a yield of 10% for obtaining soluble polymers and of 70% for obtaining insoluble polymers. These yields are low and require a very lengthy purification step (60 hours of dialysis) followed by lyophilization.

Known in the application WO0148025 (Kimberly Klarck) is a method of a preparation of a composition which consists to react a cyclodextrine on a polysaccharide for example cellulose fibers by crosslinking with a reactive anionic polymer in forming esters bounds between each other. The reactive anionic polymer comprises functional anionic groups as a cyclic acid anhydride like maleic acid anhydride and may react with a catalyst in particular with sodium hypophosphite. The reactive anionic polymer as used in the examples is a terpolymer of maleic anhydride/vinylacetate/ethylacetate BELCLENE DP80® (Durable Press 80). The cyclodextrin polycondensate as formed has a weak encapsulation capacity of a beneficial active ingredient like a perfume and the time of release is insufficiently long.

There remains therefore the need to provide novel cyclodextrin polymers which can capture and/or encapsulate large amounts of substances with a view to releasing them, without the drawbacks previously mentioned, and which can be easily prepared without the use of toxic and/or expensive reagents. In order to overcome the prior art drawbacks, the objective of the present invention is to immobilize cyclodextrins in a crosslinked polymeric network having absorbent properties and functioning like a sponge.

After considerable research, the applicant has discovered, surprisingly and unexpectedly, that it is possible to efficiently, rapidly and inexpensively immobilize cyclodextrins in a crosslinked polymeric network by esterification/polycondensation reaction of polycarboxylic acid(s) simultaneously with a thermoplastic polyol polymer and a cyclodextrin, and that these water-insoluble crosslinked cyclodextrin polycondensates lead to improved performance levels in terms of encapsulation capacity while at the same time being conveyable in numerous supports, it being possible to subsequently release the encapsulated compounds, under the action or not of an external stimulus.

This discovery forms the basis of the present invention.

The present invention relates to a composition which makes possible the release of a beneficial agent comprising at least one beneficial agent and a support comprising at least one water-insoluble cyclodextrin polycondensate which can be obtained by esterification/polycondensation reaction:

A) of at least one cyclodextrin and

B) of at least one saturated or unsaturated or aromatic, linear or branched or cyclic polycarboxylic acid and/or at least one ester or one acid anhydride or one acid halide of said polycarboxylic acid and

C) of at least one thermoplastic polyol polymer and

D) optionally of at least one esterification catalyst and/or

E) optionally of at least one cyclic anhydride of a polycarboxylic acid chosen to be other than the polycarboxylic acid anhydride of paragraph B) and/or

F) optionally of at least one non-polymeric polyol comprising from 3 to 6 hydroxyl groups.

Another subject of the invention consists of a consumer product comprising at least one composition which makes possible the release of a beneficial agent as defined previously.

More particularly, the consumer product relates to a cosmetic or dermatological composition comprising a physiologically acceptable medium. In addition, the invention relates to a process for cosmetic treatment of a keratin material, consisting in applying, to the surface of said human keratin material, a consumer product comprising a composition as defined above containing, in a physiologically acceptable medium, at least one beneficial agent chosen from cosmetic active agents.

Definitions For the purpose of the invention, the term "polycondensate" is intended to mean any polymer obtained by polymerization in steps where each step is a condensation reaction which is carried out with elimination of water or of an alcohol or of a halogenated acid in the case of an esterification. Monomers with two or more functional groups react so as to first form dimers, then trimers and longer oligomers, then long-chain polymers.

The term "water-insoluble cyclodextrin polycondensate" is intended to mean any cyclodextrin polycondensate which has a solubility in water at 25°C of less than 1% by weight, even less than 0.5% by weight, or even less than 0.1% by weight.

For the purpose of the present invention, the term "physiologically acceptable medium" is intended to mean a medium that is suitable for the topical administration of a composition.

A physiologically acceptable medium is preferably a cosmetically or dermatologically acceptable medium, that is to say a medium which is devoid of unpleasant odour or appearance and which is entirely compatible with the topical administration route.

The term "keratin materials" is intended to mean the skin, hides, the scalp, the lips, and/or the skin appendages such as the nails and keratin fibres, such as, for example, animal furs, body hair, wool, the eyelashes, the eyebrows and the hair.

The term "human keratin materials" is intended to mean the skin, the scalp, the lips, and/or the skin appendages such as the nails and human keratin fibres, such as, for example, body hair, the eyelashes, the eyebrows and the hair. For the purpose of the invention, the term "cosmetic composition" is intended to mean any composition which has a non-therapeutic hygiene, care, conditioning or makeup effect contributing to improving the well- being and/or to making more attractive and/or modifying the appearance of the keratin material to which said composition is applied.

The term "consumer product" is intended to mean any manufactured product intended to be used or consumed in the form in which it is sold and which is not intended for subsequent manufacture or modification. Without the examples being limiting, the consumer products according to the invention may be cosmetic products including both cosmetic formulations and application supports or articles comprising such formulations, such as patches, wipes, nonwoven supports; intimate hygiene products including care and hygiene formulations and also articles intended for this purpose, such as sanitary tampons, wipes, towels; products for oral hygiene, such as toothpastes, mouth care products, deodorants such as sprays, breath lozenges, chewing gums, sweets; cosmetic or dermatological products: creams, milks, lotions, balms, sticks, talcs; makeup products; hair products; babycare products including formulations and articles intended for this purpose, such as wipes, nappies; pharmaceutical products and also medical and paramedical articles such as dressings, patches, prostheses; products for veterinary use, such as animal litters; animal hygiene and/or care products; household products such as laundry care and/or cleaning products (laundry detergents, softeners), washing-up products, products for cleaning and/or maintaining household appliances, products for cleaning and/or maintaining floors, tiles, wood, etc; sanitary products such as deodorants, descaling products, unblocking products; textile materials, clothing, fine leather goods such as shoes, soles and products for the maintenance thereof; products resulting from the food-processing industry; products resulting from agriculture; phytosanitary products; products resulting from the wood and paper industry; paints; inks. For the purpose of the invention, the term "beneficial agent" is intended to mean any chemical compound present in a consumer product which produces a beneficial effect noticed by the consumer during use thereof and/or obtained on the consumer product itself, it being possible for said beneficial effect to be a sensory improvement or a modification, in particular a visual and/or olfactory and/or gustative and/or tactile improvement, an improvement of the comfort and/or ease of application, an aesthetic effect, a hygiene effect, a feeling of cleanliness, a curative and/or prophylactic effect.

The term "composition which makes possible the release of a beneficial agent" is intended to mean a composition comprising at least one beneficial agent immobilized, captured and/or encapsulated, in part or completely, in the matrix of an encapsulating or trapping system, said beneficial agent being released towards the outside as the encapsulating or trapping system deteriorates when the degradation thereof occurs on contact with a medium with which it will react or under the effect of a stimulus, such as a rise in the temperature by contributing heat, a contribution of water or any other constituent or mixture of constituents capable of being complexed in a more stable fashion than the encapsulated beneficial agent.

CYCLODEXTRIN POLYCONDENSATES

The cyclodextrin polycondensates according to the invention can be easily prepared, in a single synthesis step, and without producing waste, at low cost, in particular by carrying out the reaction in an extruder. Moreover, it is easily possible to modify the structure and/or the properties of the cyclodextrin polycondensates according to the invention, by varying the chemical nature of the various constituents and/or the proportions thereof. The cyclodextrin polycondensates according to the invention make it possible to generate a porous polymeric network which combines sponge- type superabsorbent properties with the capacity to form inclusion complexes in the cavities of cyclodextrins immobilized within the polymeric network. The cyclodextrin polycondensates according to the invention can be obtained by esterification/polycondensation, according to methods known to those skilled in the art, of the constituents described hereinafter.

CYCLODEXTRINS

One of the constituents required for the preparation of the cyclodextrin polycondensates according to the invention is a cyclodextrin.

For the purpose of the invention, the term "cyclodextrin" is intended to mean any compound of general structure

or a derivative thereof, such as methylated, hydroxyalkylated, sulfoalkylated or sulfated derivatives, or cyclodextrins substituted with sugars.

Among the cyclodextrins or derivatives thereof which are preferred, mention may be made of a-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, and methylated derivatives thereof such as TRIMEBs (heptakis(2,3,6- trimethyl)-3-CD), DIMEBs (heptakis(2,6-dimethyl)-3-CD) or else RAMEBs (Randomly Methylated β-Cyclodextrins); hydroxyalkylated derivatives thereof such as 2-hydroxypropyl-3-cyclodextrin (ΗΡβΟϋ; Kleptose® HPB), 3-hydroxypropyl-3-cyclodextrin, 2,3-dihydroxypropyl-3-cyclodextrin, 2-hydroxyethyl-3-cyclodextrin, 2-hydroxypropyl-Y-cyclodextrin and 2-hydroxyethyl-Y-cyclodextrin; sulfobutylated derivatives thereof such as sulfobutyl ether β-cyclodextrin sodium salt (SBE3CD; Captisol®); sulfated cyclodextrins such as β-cyclodextrin sulfate; cyclodextrins substituted with sugars, such as glucosyl-3-cyclodextrin, diglucosyl-3-cyclodextrin, maltosyl-3-cyclodextrin or dimaltosyl-3-cyclodextrin. A mixture of such cyclodextrins may obviously be used.

Preferably, the cyclodextrin is chosen from a-cyclodextrin, β-cyclodextrin, γ-cyclodextrin and mixtures thereof, and even better still β-cyclodextrin. The cyclodextrin(s) preferably represent(s) 10% to 70% by weight, in particular 20% to 65% by weight and better still 30% to 60% by weight of the total weight used in the synthesis of the cyclodextrin polycondensate.

POLYCARBOXYLIC ACIDS AND DERIVATIVES THEREOF a) Polycarboxylic acids

Another constituent required for the preparation of the cyclodextrin polymers according to the invention is a saturated or unsaturated or aromatic, linear or branched or cyclic polycarboxylic acid comprising at least 2 carboxylic COOH groups, preferably 2 to 4 COOH groups.

Said polycarboxylic acid may in particular be chosen from saturated or unsaturated, or even aromatic, linear, branched and/or cyclic polycarboxylic acids containing 2 to 50 carbon atoms, especially 2 to 40, in particular 3 to 36 carbon atoms, or even 3 to 18 and even better still 4 to 12 carbon atoms, or even 4 to 10 carbon atoms; said acid comprises at least two carboxylic COOH groups and preferably from 2 to 4 COOH groups.

Among the polycarboxylic acids that may be used, mention may be made, alone or as a mixture, of:

- icarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, malic acid, tartaric acid, tartronic acid, citramalic acid, dioxymaleic acid, dioxymalonic acid, maleic acid, fumaric acid, glutaconic acid, itaconic acid, fatty acid (in particular C ₃ 6 fatty acid) dimers, such as the products sold under the names Pripol 1006, 1009, 1013 and 1017 by Uniqema, glutamic acid, aspartic acid, oxaloacetic acid, cyclopropanedicarboxylic acid, cyclohexanedicarboxylic acid, cyclobutanedicarboxylic acid, naphthalene-1 ,4-dicarboxylic acid, naphthalene-2,3-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, phthalic acid, terephthalic acid, isophthalic acid, tetrahydrophthalic acid or hexahydrophthalic acid;

- tricarboxylic acids such as citric acid, aconitic acid, isocitric acid, oxalosuccinic acid, 1 ,2,3-propanetricarboxylic acid, 1 ,2,5-pentane- tricarboxylic acid, 1 ,3,5-pentanetricarboxylic acid, transaconitic acid, 3-butene-1 ,2,3-tricarboxylic acid, 3-butene-1 , 1 ,3-tricarboxylic acid, 1,3,5- cyclohexanetricarboxylic acid, trimellitic acid, 1 ,2,3-benzenetricarboxylic acid or 1 ,3,5-benzenetricarboxylic acid;

- tetracarboxylic acids such as 1 ,2,3,4-butanetetracarboxylic acid, pyromellitic acid, oxydisuccinic acid, thiodisuccinic acid, N-[1,2- dicarboxyethyl]-L-aspartic acid, ethylenediaminetetraacetic acid, ethylenediaminetetrapropionic acid or N,N'-ethylenedi(L-aspartic) acid. Preferably, said polycarboxylic acid, used alone or as a mixture, is aliphatic, saturated and linear and contains 2 to 36 carbon atoms, in particular 3 to 18 carbon atoms, or even 4 to 12 carbon atoms; or alternatively is aromatic and contains 8 to 12 carbon atoms. It preferably comprises 2 to 4 COOH groups.

Preferably, use may be made of citric acid, aconitic acid, tartaric acid, 1 ,2,3-propanetricarboxylic acid and 1 ,2,3,4-butanetetracarboxylic acid, alone or as a mixture, preferably alone, and even better still citric acid alone. b) Polycarboxylic acid esters

Among the polycarboxylic acid ester derivatives, mention may be made of the C1-C4 alkyl mono-, di-, tri- or tetraesters, in particular the methyl, ethyl, isopropyl or n-butyl esters and more preferentially the methyl or ethyl esters. The preferred polycarboxylic acid esters are the methyl, ethyl, isopropyl or n-butyl esters and more preferentially the methyl or ethyl esters of aliphatic, saturated, linear polyacids (2 to 4 COOH groups) containing 2 to 36 carbon atoms, in particular 3 to 18 carbon atoms, or even 4 to 12 carbon atoms; or alternatively of an aromatic acid containing 8 to 12 carbon atoms.

Preferably, use may be made of the methyl, ethyl, isopropyl or n-butyl esters and more preferentially the ethyl or butyl esters of citric acid, of aconitic acid, of tartaric acid, of 1 ,2,3-propanetricarboxylic acid and of 1 ,2,3,4-butanetetracarboxylic acid, alone or as a mixture, and even better still the ethyl or butyl esters of citric acid, such as triethyl citrate, triethyl acetylcitrate, tributyl citrate and tributyl acetylcitrate. c) Polycarboxylic acid anhydrides

Among the polycarboxylic acid-derived acid anhydrides, mention may be made of mixed anhydrides with a C ₂ -C ₄ carboxylic acid (acetic, propionic or butyric acid), preferably acetic acid. Mention may also be made of cyclic anhydrides of polycarboxylic acids, such as phthalic anhydride, trimellitic anhydride, maleic anhydride, succinic anhydride or Ν,Ν,Ν',Ν'- ethylenediaminetetraacetic acid dianhydride. Preferably, the polycarboxylic acid anhydride, alone or as a mixture, is chosen from maleic anhydride and succinic anhydride and more preferentially is maleic anhydride alone. d) Polycarboxylic acid halides

Among the acid halides derived from said polycarboxylic acids, mention may be made of the acid chlorides or acid bromides of said polycarboxylic acids, preferably the polycarboxylic acid chlorides.

Preferably, the acid halides, used alone or as a mixture, are derivatives of aconitic acid, of tartaric acid, of 1 ,2,3-propanetricarboxylic acid and of 1 ,2,3,4-butanetetracarboxylic acid.

Said polycarboxylic acid(s) and/or ester, acid anhydride or acid halide derivatives thereof, used alone or as a mixture, preferably represent(s) 5% to 40% by weight, more preferentially from 7% to 35% by weight and better still 10% to 30% by weight, of the total weight used in the synthesis of the cyclodextrin polycondensate.

THERMOPLASTIC POLYOL POLYMERS

Another constituent required for the preparation of the cyclodextrin polycondensates according to the invention is a thermoplastic polyol polymer. The term "polyol polymer" is intended to mean a polymer having an average molecular weight ranging from 1000 to 200 000 Daltons, containing at least two hydroxyl functions.

The term "thermoplastic polyol polymer" is intended to mean a polyol polymer which fluidifies (softens) in heat at a temperature between 100 and 250°C.

Various types of thermoplastic polyol polymers can be used according to the invention. Mention will be made of polyether-polyols, polyester- polyols, polycarbonate-polyols, polyamide-polyols, polyurethane-polyols, polyalkylene-polyols, polycaprolactone-polyols and polysaccharides.

Among the polyether-polyols, mention will be made of polyoxyethylene glycols, polyoxypropylene glycols, block or random copolymers of ethylene oxide and of propylene oxide, block or random copolymers of ethylene oxide and/or propylene oxide with tetrahydrofuran, and more particularly polytetramethylene glycols and polypropylene glycols.

Among the polyester-polyols, mention will in particular be made of those obtained by polycondensation of dicarboxylic or tricarboxylic acids with polyols (di-, tri- or tetraols), for instance poly(hexamethylene adipate), and also those obtained by polycondensation of hydroxy acids, such as polyhydroxyalkanoates and in particular polylactic acid, polyhydroxybutyrate (PHB) and polyhydroxybutyrate-valerate (PHBV). Among the polycarbonate-polyols, mention will be made of those prepared by reacting diols (propane-1 ,3-diol, butane-1 ,4-diol, hexane-1 ,6-diol, 1,9- nonanediol, 2-methyloctane-1 ,8-diol, diethylene glycol, etc.) with diaryl carbonates, such as diphenyl carbonate, or else with phosgene. Among the polyamide-polyols, mention will be made more particularly of those obtained by reacting a diamine and/or a polymeric diamine with a dicarboxylic or polycarboxylic acid and a hydroxy acid, such as, for example, 12-hydroxystearic acid. Among the polyurethane-polyols, mention will be made of those obtained by means of a polyaddition process consisting in reacting polyisocyanates, preferably diisocyanates, with diols and/or polyols.

Among the polycaprolactone-polyols, mention will be made in particular of the polycaprolactone-polyols obtained by polymerization of epsilon- caprolactone with ring opening via polyols such as ethylene glycol, 1,2- propanediol, 1 ,3-propanediol, glycerol or trimethylolpropane.

Among the polyalkylene-polyols, mention will be made of polyvinyl alcohol, modified polyvinyl alcohol having a content of ethylene units of 4 mol% to 15 mol% and polybutadiene diols.

Among the polysaccharides, mention will be made quite particularly of thermoplastic starches which are obtained by destructuring the native granule in the presence of a plasticizer under thermomechanical stresses; cellulose derivatives, such as cellulose acetate, cellulose acetobutyrate, cellulose acetopropionate, methylcellulose, ethylcellulose, hydroxypropylcellulose, hydroxyethylcellulose, hydroxy propyl methyl- cellulose, hydroxyethylmethylcellulose or carboxymethylcellulose, alone or as a mixture with alginates, gums such as guar gum, starches such as tapioca starch, modified starches such as starch octenyl succinate (E.1450), oxidized starches (E.1404), crosslinked starches (E.1412 or 1413), stabilized starches (E.1420 or E.1440), crosslinked/stabilized starches such as acetylated distarch adipate (E.1422) or hydroxypropylated distarch phosphate (E.1442), sulfated polysaccharides such as carrageenans, aminopolysaccharides such as chitosan or chitin, oxidized polysaccharides such as those described in application WO 2010/070235, patent FR 2 944 967 and application WO 2011/161020, and more particularly starches, inulins, carrageenans, alginates and glucomannans.

Among the thermoplastic polyol polymers which can be used for the preparation of the cyclodextrin polycondensates, the polysaccharides are particularly preferred since they have a renewable origin and are available at high tonnage and at low cost.

Preferably, among the polysaccharides, use may be made, alone or as a mixture, of hydroxypropylcellulose and hydroxyethylcellulose, and even better still hydroxypropylcellulose alone. Said thermoplastic polyol polymer(s) preferably represent(s) 10% to 50% by weight, in particular 15% to 45% by weight and better still 17% to 40% by weight, of the total weight used in the synthesis of the cyclodextrin polycondensate. POLYCARBOXYLIC ACID CYCLIC ANHYDRIDES

According to one particular form of the invention, at least one polycarboxylic acid cyclic anhydride chosen so as to be other than the first polycarboxylic acid anhydride previously mentioned is also used for the preparation of the cyclodextrin polycondensates according to the invention.

The polycarboxylic acid cyclic anhydride may in particular correspond to one of the following formulae:

in which the groups A and B are, independently of one another:

- a hydrogen atom;

- a saturated or unsaturated, linear, branched and/or cyclic, or alternatively aromatic, carbon-based radical containing 1 to 16 carbon atoms, in particular 2 to 10 carbon atoms or even 4 to 8 carbon atoms, in particular methyl or ethyl;

- or alternatively A and B, taken together, form a saturated or unsaturated, or even aromatic, ring containing in total 5 to 7 and in particular 6 carbon atoms.

Preferably, A and B represent a hydrogen atom or together form an aromatic ring containing in total 6 carbon atoms. Among the polycarboxylic acid cyclic anhydrides which may be used, mention may be made of, alone or as a mixture, phthalic anhydride, trimellitic anhydride, maleic anhydride and succinic anhydride.

Preferably, use may be made of maleic anhydride and succinic anhydride alone or as a mixture, and even better still maleic anhydride alone.

When said polycarboxylic acid cyclic anhydride is present among the ingredients used, it preferably represents 0.1% to 10% by weight, in particular 0.5% to 5% by weight, or even 0.7% to 4% by weight, relative to the total weight used in the synthesis of the cyclodextrin polycondensate.

ESTERIFICATION CATALYSTS

According to one particular form of the invention, at least one esterification catalyst will be used for the preparation of the cyclodextrin polycondensates according to the invention.

The esterification catalyst may in particular be chosen from dihydrogen phosphates, hydrogen phosphates, phosphates, hypophosphites and phosphites of alkali metals, alkali metal salts of polyphosphoric acids, alkali metal or alkaline-earth metal carbonates, bicarbonates, acetates, borates and hydroxides, aliphatic amines and aqueous ammonia, optionally combined with an inorganic solid support such as alumina, silica gels, Al silicates, zeolites, titanium oxides or zirconium oxides. The esterification catalyst may also be chosen from sulfonic acids or titanates.

Use may preferably be made of sodium hydrogen phosphate, sodium dihydrogen phosphate and sodium hypophosphite.

When said esterification catalyst is present among the ingredients used, it preferably represents 0.1% to 5% by weight, in particular 0.5% to 4% by weight, or even 0.5% to 3% by weight, relative to the total weight used in the synthesis of the cyclodextrin polycondensate.

NON-POLYMERIC POLYOLS

According to one particular form of the invention, at least one non- polymeric polyol comprising 3 to 6 hydroxyl groups will also be used for the preparation of the cyclodextrin polycondensates according to the invention. A mixture of such polyols may obviously be used.

Said polyol may in particular be a linear, branched and/or cyclic, saturated or unsaturated carbon-based and in particular hydrocarbon-based compound containing 3 to 18 carbon atoms, in particular 3 to 12 or even 4 to 10 carbon atoms, and 3 to 6 hydroxyl (OH) groups, and also possibly comprising one or more oxygen atoms inserted in the chain (ether function).

Said polyol is preferably a linear or branched saturated hydrocarbon- based compound containing 3 to 18 carbon atoms, in particular 3 to 12 or even 4 to 10 carbon atoms, and 3 to 6 hydroxyl (OH) groups. It may be chosen, alone or as a mixture, from:

- triols such as 1 ,2,4-butanetriol, 1 ,2,6-hexanetriol, trimethylolethane, trimethylolpropane or glycerol;

- tetraols such as pentaerythritol (tetramethylolmethane), erythritol, diglycerol or ditrimethylolpropane;

- pentols such as xylitol;

- hexols such as sorbitol and mannitol; or alternatively dipentaerythritol or triglycerol.

Preferably, the polyol is chosen from glycerol, pentaerythritol, diglycerol and sorbitol, and mixtures thereof; and even better still the polyol is glycerol.

When said polyol comprising 3 to 6 hydroxyl groups is present among the ingredients used, it preferably represents 1% to 30% by weight, in particular 2% to 25% by weight, or even 10% to 20% by weight, relative to the total weight used in the synthesis of the cyclodextrin polycondensate .

In one preferred embodiment of the invention, the ratio between the number of moles of polycarboxylic acid and the number of moles of the cyclodextrin preferably ranges from 0.5 to 5, especially from 0.6 to 4, in particular ranging from 0.7 to 3.

It has been noted that these proportions make it possible to obtain a cyclodextrin polycondensate which is advantageously water-insoluble and which, moreover, has at the same time an appropriate capacity for both capturing and impregnating various ingredients.

Preferably, the cyclodextrin polycondensate according to the invention has an acid number, expressed in mg of potassium hydroxide per g of polycondensate, greater than or equal to 20, in particular ranging from 20 to 250 and even better still ranging from 40 to 180.

This acid number may be readily determined by those skilled in the art via the conventional analytical methods. The amount of -COOH groups present is evaluated according to the number of milligrams of potassium hydroxide required to neutralize 1 g of cyclodextrin polycondensate, the dispersion being carried out in a mixture of solvents (1 part of water and 1 part of absolute ethanol).

Preferably, the cyclodextrin polycondensate according to the invention exhibits a degree of swelling in water, measured at 20°C, greater than or equal to 100%, in particular ranging from 100% to 1000% and even better still ranging from 300% to 900%. This degree of swelling is measured in the manner described hereinafter.

Protocol for measuring the degree of swelling:

2 g of polycondensate are suspended in 20 g of demineralized water with light stirring for 24 h at ambient temperature. The suspension is centrifuged in order to separate the supernatant and then the solids content is determined on the centrifugate using a thermobalance. The % degree of swelling is obtained by calculating the evaporated weight/dry weight ratio x 100.

PREPARATION PROCESSES The cyclodextrin polycondensate according to the invention may be prepared via the esterification/polycondensation processes usually used by those skilled in the art.

By way of illustration, a general preparation process consists:

- in mixing together one or more cyclodextrins, a polycarboxylic acid and/or a derivative thereof (esters, acid anhydrides or acid halides), at least one thermoplastic polyol polymer and optionally at least one polycarboxylic acid cyclic anhydride chosen so as to be other than the previous polycarboxylic acid anhydride and/or at least one esterification catalyst and/or at least one non-polymeric polyol comprising 3 to 6 hydroxyl groups,

- in heating the mixture, preferably under an inert atmosphere, to a temperature ranging from 100 to 250°C, preferably while removing, during the heating, the water, the alcohol or the acid formed, then

- in cooling the mixture to ambient temperature. It is also possible to perform the reaction, totally or partly, in an inert solvent such as xylene and/or under reduced pressure, to facilitate the removal of the water, the alcohol or the acid formed. Advantageously, no solvent is used.

Said preparation process may also comprise a step of adding at least one antioxidant to the reaction medium, in particular in a weight concentration of between 0.01% and 2% relative to the total weight of monomers, so as to limit the possible degradation associated with prolonged heating.

The antioxidant may be of primary type or secondary type and may be chosen from hindered phenols, aromatic secondary amines, organophosphorus compounds, sulfur compounds, lactones and bisphenols, and mixtures thereof.

Among the antioxidants that are particularly preferred, mention may in particular be made of BHT, BHA, TBHQ, 1 ,3,5-trimethyl-2,4,6,tris(3,5-di- (te rt-b u ty I )-4-hydroxy benzyl) benzene, octadecyl 3,5,di-(tert-butyl)-4- hydroxycinnamate, tetra kis [methyl en e-3-(3,5-di-(te rt-b uty I )-4- hydroxyphenyl)propion ate] methane, octadecyl 3-(3,5-di-(tert-butyl)-4- hydroxyphenyl propionate, 2,5-di-(tert-butyl)hydroquinone, 2,2-methylene- bis(4-methyl-6-(tert-butyl)phenol), 2,2-methylenebis(4-ethyl-6-(tert-butyl)- phenol), 4,4-butylidenebis(6-(tert-butyl)-m-cresol), N,N-hexamethylene- bis(3,5-di-(tert-butyl)-4-hydroxyhydrocinnamamide), pentaerythrityl tetrakis(3-(3,5-di-(tert-buty I )-4-hydroxy phenyl propionate), in particular the product sold by Ciba under the name Irganox 1010; octadecyl 3-(3,5- di-(tert-butyl)-4-hydroxphenyl)propionate, in particular the product sold by Ciba under the name Irganox 1076; 1 ,3,5-tris(3,5-di-(tert-butyl)-4- hydroxybenzyl)-1 ,3,5-triazine-2,4,6(1 H,3H,5H)-trione, in particular the product sold by Mayzo of Norcross, Ga under the name BNX 3114; di(stearyl)pentaerythritol di phosphite, tris(2,4-di-(tert-butyl)phenyl)- phosphite, in particular the product sold by Ciba under the name Irgafos 168; dilauryl thiodipropionate, in particular the product sold by Ciba under the name Irganox PS800; bis(2,4-di-(tert-butyl)pentaerythritol diphosphite, in particular the product sold by Ciba under the name Irgafos 126; bis(2,4- bis)[2-phenylpropan-2-yl]phenyl)pentaerythritol diphosphite, triphenyl- phosphite, (2,4-di-(tert-butyl)phenyl)pentaerythritol diphosphite, in particular the product sold by GE Specialty Chemicals under the name Ultranox 626; tris(nonylphenyl)phosphite, in particular the product sold by Ciba under the name Irgafos TNPP; the 1:1 mixture of N,N- hexamethylenebis(3,5-di-(tert-butyl)-4-hydroxyhydrocinnamami de) and of tris(2,4-di-(tert-butyl)phenyl)phosphate, in particular the product sold by Ciba under the name Irganox B 1171; tetrakis(2,4-di-(tert- butyl)phenyl)phosphite, in particular the product sold by Ciba under the name Irgafos P-EPQ; distearyl thiodipropionate, in particular the product sold by Ciba under the name Irganox PS802; 2,4-bis(octylthiomethyl)-o- cresol, in particular the product sold by Ciba under the name Irganox 1520; 4,6-bis(dodecylthiomethyl)-o-cresol, in particular the product sold by Ciba under the name Irganox 1726.

One particularly preferred mode of preparation of the cyclodextrin polycondensates of the present invention consists in mixing at least one cyclodextrin, at least one polycarboxylic acid and/or an ester, acid anhydride or acid halide derivative thereof, at least one thermoplastic polyol polymer and optionally at least one polycarboxylic acid cyclic anhydride chosen to be other than the previous polycarboxylic acid anhydride and/or optionally at least one esterification catalyst and/or optionally at least one non-polymeric polyol, in an apparatus which makes it possible to bring the mixture to a thermoplastic state by combining sufficient temperature and shear force conditions, thus making the various components compatible.

Preferably, use will be made of an extruder, for instance of the Clextral BC 21® twin-screw type or any other apparatus which can meet these criteria, which preferably operates at a temperature ranging from 100 to 250°C and preferentially from 110 to 200°C.

The preferred mode of preparation of the cyclodextrin polycondensates according to the invention consists in incorporating, in a single step, all the ingredients in an extruder at a temperature ranging from 110 to 200°C, preferably ranging from 120 to 190°C and even better still from 150 to 180°C.

The residence time in an extruder preferably ranges from 1 to 10 minutes and even better still from 1 to 5 minutes.

Depending on the purpose for which the cyclodextrin polycondensate of the invention is intended, said polycondensate may subsequently be ground if required.

BENEFICIAL AGENTS

The cyclodextrin polycondensates of the invention exhibit a porous network which combines superabsorbent properties of sponge type with the ability to form inclusion complexes in the cyclodextrin cavities immobilized within the polymeric network, thus making it possible to capture one or more beneficial agents having an affinity with said polymeric network and to release them, in particular on contact with an aqueous medium or with heat, such as, for example, the contact with the skin or hair and/or the contact with perspiration, with or without an additional stimulus.

The compositions which make possible the release of a beneficial agent in accordance with the invention generally comprise some or all of said beneficial agent or agents captured and/or encapsulated in the polymeric network of the cyclodextrin polycondensate.

The amount of beneficial agent(s) present in the polycondensate will vary according to the nature of the cyclodextrin polycondensate chosen, according to the chemical nature and the affinity of the beneficial agent with regard to said polycondensate, according to the need or not to release the beneficial agent in a significant amount, according to the need or not to release the beneficial agent over a long period of time, according to the nature of the area to which the composition must be applied, indeed even according to the nature or the intensity of the stimulus, if a stimulus must be applied, and more generally according to the requirements of a person skilled in the art.

In order to prepare the compositions which make possible the release of a beneficial agent according to the invention comprising one or more beneficial agents and a cyclodextrin polycondensate including them, it is possible to proceed in the following way:

a) the cyclodextrin polycondensate as described above is prepared and then said polycondensate is optionally ground,

b) the beneficial agent or the mixture of beneficial agents is impregnated (encapsulated) within the polycondensate by bringing said beneficial agents into static contact (blotter effect) or into contact with stirring for a time generally of between 1 hour and 24 hours (with the cyclodextrin polycondensate), which agents are pure or conveyed in a solvent or a mixture of solvents, such as water alone, an alcohol, such as ethanol or glycerol, a ketone, such as acetone, or their essentially aqueous mixtures or also in a fluid in a sub- or supercritical state, such as C0 ₂ or water.

Either the amount of beneficial agent(s) which it is desired to encapsulate or an excess of the latter can be added to the cyclodextrin polycondensate. In the latter case, the excess is separated by any appropriate means, such as, for example, centrifugation or filtration. The polycondensate, thus impregnated with beneficial agent(s), is generally left to dry in dry air before it is employed for the purpose of the release of the beneficial agents.

When the nature of the beneficial agents to be encapsulated in the polycondensate lends itself thereto, it is also possible to incorporate them during the stage of synthesis of the polycondensate, in particular when the synthesis is carried out, for example, in an extruder.

When the beneficial agents to be encapsulated in the polycondensate have a specific affinity sufficient for the polycondensate, it is also possible to incorporate the cyclodextrin polycondensate in the final implementational composition and then to add the beneficial agent(s) to said composition. The amount of beneficial agent present in the cyclodextrin polycondensate preferably varies from 1% to 100% by weight and more preferably from 10% to 90% and better still from 20% to 80%, relative to the total weight of the polycondensate.

The time for release of the beneficial agent will also vary according to the nature of the cyclodextrin polycondensate chosen and according to the chemical nature and the affinity of the beneficial agent with regard to said polycondensate or according to the nature of the area to which the composition must be applied, indeed even according to the nature or the intensity of the stimulus, if a stimulus must be applied.

The total period of time for releasing the beneficial agent will be highly dependent on the nature, in particular chemical nature, of the beneficial agent, on the amount encapsulated in the polycondensate and on the nature and on the intensity of the stimulus to which the polycondensate containing the beneficial agent will be subjected. It is possible to vary this total period of time for release into a large range of times which can extend from a few minutes to a few weeks, which constitutes another advantage of the polycondensates including beneficial agents of the invention. For example, it has been found that, at 150°C, the total period of time for release was generally between 15 minutes and 2 hours. For example, it has also been found that, at a temperature of 37°C and with addition of water, the total period of time for release was greater than 24 hours and could even exceed 72 hours, indeed even reach or exceed a week.

Mention may more particularly be made, among the beneficial agents which can be used according to the invention, of:

(i) fatty substances;

(ii) flavouring substances and/or taste enhancers;

(iii) fragrancing substances;

(iv) pharmaceutical active ingredients;

(v) cosmetic active agents. a) Fatty substances Fatty substances are commonly used in the formulation of pharmaceutical, cosmetic and/or food-processing compositions. They may be chosen from the group comprising:

(i) natural oils of vegetable, animal or marine origin, such as olive oil, sesame oil, argan oil, palm oil, soya bean oil, woad oil, turtle oil, babassu oil, aloe vera, avocado oil, allantoin, bisabol, grapeseed oil, apricot oil, wheat germ oil, almond oil, groundnut oil, macadamia nut oil, buckthorn oil, evening primrose oil, borage oil, ginger oil, geraniol, jujube oil, mink oil or lanolin,

(ii) synthetic oils,

(iii) mineral oils, such as isohexadecane, para-isoparaffin, ceresin or petroleum jelly,

(iv) hydrogenated oils,

(v) silicone oils,

(vi) hydrocarbon-based compounds, such as paraffin oil,

(vii) terpenes,

(viii) squalene,

(ix) saturated or unsaturated fatty acids, such as myristic acid,

(x) fatty acid esters,

(xi) waxes, beeswax, jojoba oil which is in fact a liquid wax, ester waxes,

(xii) fatty alcohols, such as myristyl alcohol, cetyl alcohol, stearyl alcohol or myricyl alcohol,

(xiii) butters, such as shea butter or cocoa butter,

(xiv) or a mixture thereof.

One of the possible applications according to the invention is the conveying of fatty substances for cosmetic use or for food use or for dietary cosmetic use, such as nutritive supplements. b) Flavouring substances and taste enhancers

One of the possible applications according to the invention is the conveying of flavouring substances and/or of taste enhancers for food use or for dietary cosmetic use, such as nutritive supplements. 1) Flavouring substances

Among the flavouring substances, mention may be made of those chosen:

(i) from those indicated in the official list established by the European Council in the publication Substances aromatisantes et sources naturelles de matieres aromatisantes [Flavouring substances and natural sources of flavouring materials], vol. 1, 4th edition, 1992, Maisonneuve;

(ii) from those indicated in the FEMA/GRAS official lists published by the Food and Drug Administration (FDA).

2) Flavour enhancers

The European Union defines flavour enhancers in the list of food additives via an E number. They are numbered from E620 (glutamic acid) to E641 (L-leucine).

Among the flavour enhancers, mention may be made of

i) glutamates such as glutamic acid (E620), monosodium glutamate (E621), monopotassium glutamate (E622), calcium diglutamate (E623), ammonium glutamate (E624) or magnesium diglutamate (E625);

(ii) guanylates such as guanylic acid or guanisine monophosphate

(E626), disodium guanylate (E627), dipotassium guanylate (E628) or calcium guanylate (E629);

(iii) inosinates such as inosinic acid (E630), disodium inosinate (E631), dipotassium inosinate (E632) or calcium inosinate (E633).

Mention may also be made of calcium 5'-ribonucleotide (E634), disodium 5'-ribonucleotide (E635), maltol (E636), ethylmaltol (E637), glycine (E640) and L-leucine (E641 ).

Mention may also be made of the following additives considered to be enhancers: lactic acid (acidifier) (E270), sweeteners such as acesulfame- K (E950), aspartame (E951), thaumatin (E957), neohesperidin dihydrochalcone (E959), neotame (E961) or erythritol (E968). c) Fragrancing substances The term "fragrancing substance" is intended to mean any fragrance or aroma capable of giving off a pleasant odour.

Fragrances are compositions in particular containing the starting materials described in S. Arctander, Perfume and Flavor Chemicals (Montclair, N.J., 1969), in S. Arctander, Perfume and Flavor Materials of Natural Origin (Elizabeth, N.J., 1960) and in Flavor and Fragrance Materials - 1991, Allured Publishing Co., Wheaton, III.

They may also be natural products, for instance essential oils, absolutes, resinoids, resins, concretes, and/or synthetic products (terpene or sesquiterpene hydrocarbons, alcohols, phenols, aldehydes, ketones, ethers, acids, esters, nitriles or peroxides, which may be saturated or unsaturated, and aliphatic or cyclic). According to the definition given in international standard ISO 9235 and adopted by the Commission of the European Pharmacopoeia, an essential oil is an odorous product generally of complex composition, obtained from a botanically defined plant starting material, either by steam distillation, or by dry distillation, or via an appropriate mechanical method without heating (cold pressing). The essential oil is generally separated from the aqueous phase by a physical method which does not result in any significant change in the composition.

Among the essential oils that may be used according to the invention, mention may be made of those obtained from plants belonging to the following botanical families:

Abietaceae or Pinaceae: conifers; Amaryllidaceae; Anacardaceae; Anonaceae: ylang ylang; Apiaceae (for example Umbelliferae): dill, angelica, coriander, sea fennel, carrot, parsley; Araceae; Aristolochiaceae; Asteraceae: yarrow, artemisia, camomile, helichrysum; Betulaceae; Brassicaceae; Burseraceae: frankincense; Carophyllaceae; Canellaceae; Cesalpiniaceae: copaifera (copaiba balsam); Chenopodaceae; Cistaceae: rock rose; Cyperaceae; Dipterocarpaceae; Ericaceae: gaultheria (wintergreen); Euphorbiaceae; Fabaceae; Geraniaceae: geranium; Guttiferae; Hamamelidaceae; Hernandiaceae; Hypericaceae: St. John's wort; Iridaceae; Juglandaceae; Lamiaceae: thyme, oregano, monarda, savory, basil, marjorams, mints, patchouli, lavenders, sages, catnip, rosemary, hyssop, balm; Lauraceae: ravensara, sweet bay, rosewood, cinnamon, litsea; Liliaceae: garlic; Magnoliaceae: magnolia; Malvaceae; Meliaceae; Monimiaceae; Moraceae: hemp, hop; Myricaceae; Myristicaceae: nutmeg; Myrtaceae: eucalyptus, tea tree, paperbark tree, cajuput, backhousia, clove, myrtle; Oleaceae; Piperaceae: pepper; Pittosporaceae; Poaceae: lemon balm, lemongrass, vetiver; Polygonaceae; Renonculaceae; Rosaceae: roses; Rubiaceae; Rutaceae: all citrus plants; Salicaceae; Santalaceae: sandalwood; Saxifragaceae; Schisandraceae; Styracaceae: benzoin; Thymelaceae: agar wood; Tilliaceae; Valerianaceae: valerian, spikenard; Verbenaceae: lantana, verbena; Violaceae; Zingiberaceae: galanga, turmeric, cardamom, ginger; Zygophyllaceae. Mention may also be made of the essential oils extracted from flowers (lily, lavender, rose, jasmine, ylang ylang, neroli), from stems and leaves (patchouli, geranium, petitgrain), from fruit (coriander, aniseed, cumin, juniper), from fruit peel (bergamot, lemon, orange), from roots (angelica, celery, cardamom, iris, rattan palm, ginger), from wood (pinewood, sandalwood, gaiac wood, rose of cedar, camphor), from grasses and gramineae (tarragon, rosemary, basil, lemongrass, sage, thyme), from needles and branches (spruce, fir, pine, dwarf pine) and from resins and balms (galbanum, elemi, benzoin, myrrh, olibanum, opopanax). Examples of fragrancing substances are in particular: geraniol, geranyl acetate, farnesol, borneol, bornyl acetate, linolool, linalyl acetate, linalyl propionate, linalyl butyrate, tetrahydrolinolool, citronellol, citronellyl acetate, citronellyl formate, citronellyl propionate, dihydromyrcenol, dihydromyrcenyl acetate, tetrahydromyrcenol, terpineol, terpinyl acetate, nopol, nopyl acetate, nerol, neryl acetate, 2-phenylethanol, 2-phenylethyl acetate, benzyl alcohol, benzyl acetate, benzyl salicylate, styrallyl acetate, benzyl benzoate, amyl salicylate, dimethylbenzylcarbinol, trichloromethylphenylcarbinyl acetate, p-tert-butylcyclohexyl acetate, isononyl acetate, vetiveryl acetate, vetiverol, a-hexylcinnamaldehyde,

2- methyl-3-(p-tert-butylphenyl)propanal, 2-methyl-3-(p- isopropylphenyl)propanal, 3-(p-tert-butylphenyl)propanal, 2,4- dimethylcyclohex-3-enylcarboxaldehyde, tricyclodecenyl acetate, tricyclodecenyl propionate, 4-(4-hydroxy-4-methylpentyl)-3- cyclohexenecarboxaldehyde, 4-(4-methyl-3-pentenyl)-3- cyclohexenecarboxaldehyde, 4-acetoxy-3-pentyltetrahyd ropy ran, 3-carboxymethyl-2-pentylcyclopentane, 2-n-4-heptylcyclopentanone,

3- methyl-2-pentyl-2-cyclopentenone, menthone, carvone, tagetone, geranylacetone, n-decanal, n-dodecanal, 9-decen-1 -ol, phenoxyethyl isobutyrate, phenylacetaldehyde dimethyl acetal, phenylacetaldehyde diethyl acetal, geranonitrile, citronel Ion itrile, cedryl acetate, 3-isocamphylcyclohexanol, cedryl methyl ether, isolongifolanone, aubepinonitrile, aubepine, heliotropin, coumarin, eugenol, vanillin, diphenyl ether, citral, citronellal, hydroxycitronellal, damascone, ionones, methylionones, isomethylionones, solanone, irones, cis-3-hexenol and esters thereof, musk-indans, musk-tetralins, musk-isochromans, macrocyclic ketones, musk-macrolactones, aliphatic musks, ethylene brassylate and rose essence, and mixtures thereof.

Another of the possible applications is, for example, the conveying of fragrancing substances for the manufacture of perfumery products (fragrances, eaux de toilette, eaux de parfum, aftershave lotions), cosmetic products for caring for and/or cleansing keratin materials, in particular human keratin materials, makeup products, laundry cleaning and/or care products, household products, in the manufacture of clothing, shoes, soles and products for the maintenance thereof, in products intended for animal hygiene, such as litters, in inks, products resulting from the paper industry, in products intended for babycare (wipes, nappies), in products intended for intimate hygiene (tampons, wipes, towels), in products for sanitary use, and in food-processing products and products resulting from agriculture. d) Pharmaceutical active ingredients The term "pharmaceutical active ingredient" is intended to mean a molecule which has a curative and/or prophylactic therapeutic effect. For example, it may be any molecule with therapeutic properties which is part of the composition of a medicament. Mention may be made, for example, of non-steroidal anti-inflammatory drugs (NSAIDs), abortifacients, alpha-blockers, alpha2-agonists, aminosides, analgesics, anaesthetics, local anaesthetics, anorexigenics, 5HT3 antagonists, calcium antagonists, anti-angina agents, antiarrhythmics, antibiotics, anticholinergics, anticholinesterases, antidiabetics, anti-diarrhoea agents, antidepressants, antihistamines, antihypertensives, antimycotics, antimalarials, antiparasitics, antipsychotics, antipyretics, antiretrovirals, antiseptics, antispasmodics, antivirals, antiemetics, antiepileptics, anxiolytics, barbiturates, benzodiazepines, bronchodilators, beta-blockers, chemotherapy agents, corticosteroids, diuretics, loop diuretics, osmotic diuretics, depressants, glucocorticoids, hallucinogenics, hypnotics, immunosupressants, carbonic anhydrase inhibitors, neuraminidase inhibitors, proton pump inhibitors, TNF inhibitors, selective serotonin reuptake inhibitors, HMG-CoA reductase inhibitors (or statins), keratolytics, laxatives, mineralocorticoids, muscle relaxants, neuroleptics, psychotropics, spasmolytics, stimulants, sedatives, tocolytics or vasodilators. This list is not exhaustive and extends to any therapeutic active ingredient known to those skilled in the art. e) Cosmetic active agents

The term "cosmetic active agent" is intended to mean any molecule which has a hygiene, care, makeup or dyeing effect contributing to improving the well-being and/or to making more attractive or modifying the appearance of the human keratin material to which said composition is applied.

The cosmetic active agents can therefore be chosen from any of the substances which meet this definition and which are present in products such as

(i) hygiene products: makeup-removing products, toothpastes, deodorants, antiperspirants, shower gels, bath preparations (bubble bath, bath oil, bath salts), intimate cleansing gels, soaps, shampoos,

(ii) care products: antiwrinkle cream, day cream, night cream, moisturizing cream, floral water, scrubbing product, milk, beauty mask, lip balm, tonic,

(iii) hair care and/or treatment products, such as styling products, dyeing products, permanent-waving products, conditioning products: conditioner, hair relaxing product, hair straightening product; gel, oil, lacquer, mask, anti-dandruff agents,

(iv) makeup products: concealer, eyeliner, face powder, foundation, khol, mascara, powder, skin whitening product, lipstick, nail varnish,

(v) fragrances: eau de Cologne, eau de toilette, perfume,

(vi) suntan products: self-tanning products, aftersun creams, milks, oils, sticks or lotions and anti-sun products,

(vii) shaving products and hair removal products: aftershave, hair removal cream, shaving foam and gels.

Among the active agents for caring for human keratin materials such as the skin, the lips, the scalp, the hair, the eyelashes or the nails, examples that may be mentioned include:

- vitamins and derivatives or precursors thereof, alone or as mixtures; - antioxidants;

- cleansing agents;

- hair dyes;

- conditioning agents;

- hair relaxing and/or straightening and/or shaping agents;

- free-radical scavengers;

- agents for combating pollutants;

- photoprotective agents such as organic screening agents, inorganic UV- screening agents;

- self-tanning agents;

- antiglycation agents;

- soothing agents;

- hair removal agents;

- deodorants;

- antiperspirants;

- essential oils;

- NO-synthase inhibitors; - agents which stimulate the synthesis of dermal or epidermal macromolecules and/or which prevent degradation thereof;

- agents which stimulate the proliferation of fibroblasts;

- agents which stimulate the proliferation of keratinocytes;

- dermo-relaxing agents;

- refreshing agents;

- tensioning agents;

- mattifying agents;

- depigmenting agents;

- propigmenting agents;

- keratolytic agents;

- desquamating agents;

- moisturizing agents;

- antimicrobial agents;

- slimming agents;

- agents which act on the energy metabolism of cells;

- insect repellents;

- substance-P or CGRP antagonists;

- agents for combating hair loss;

- antiwrinkle agents;

- anti-ageing agents;

- anti-dandruff agents.

The cyclodextrin polycondensates according to the invention can be used very advantageously in a cosmetic or dermatological composition which comprises, moreover, a physiologically acceptable medium.

The amount of cyclodextrin polycondensate present in the compositions obviously depends on the type of composition and on the desired properties and may vary within a very wide range, generally ranging from 0.1% to 100% by weight, preferably from 0.5% to 95% by weight, in particular from 1% to 70% by weight, or even from 1.5% to 50% by weight and better still from 2% to 20% by weight, relative to the total weight of the composition.

The composition may thus comprise, depending on the intended application, constituents that are common for this type of composition.

The composition according to the invention may advantageously comprise at least one fatty phase which may comprise at least one compound chosen from volatile or non-volatile carbon-based, hydrocarbon-based, fluoro and/or silicone oils, waxes and/or solvents of mineral, animal, plant or synthetic origin, alone or as a mixture, provided that they form a stable, homogeneous mixture and are compatible with the intended use. For the purpose of the invention, the term "volatile" is intended to mean any compound that is capable of evaporating on contact with keratin materials in less than one hour, at ambient temperature (25°C) and atmospheric pressure (1 atm). In particular, this volatile compound has a non-zero vapour pressure, at ambient temperature and atmospheric pressure, ranging from 0.13 Pa to 40 000 Pa (10 ^"3 to 300 mmHg), in particular ranging from 1.3 Pa to 13 000 Pa (0.01 to 100 mmHg), and more particularly ranging from 1.3 Pa to 1300 Pa (0.01 to 10 mmHg).

In contrast, the term "non-volatile" is intended to mean a compound that remains on human keratin materials at ambient temperature and atmospheric pressure for at least one hour and that in particular has a vapour pressure of less than 10 ^"3 mmHg (0.13 Pa).

The fatty phase may represent from 1% to 99% by weight of the composition, especially from 5% to 95% by weight, in particular from 10% to 90% by weight, or even from 20% to 85% by weight, of the total weight of the composition.

The composition may also comprise other ingredients commonly used in cosmetic compositions. Such ingredients may be chosen from antioxidants, fragrances, essential oils, preservatives, cosmetic active agents, moisturizers, vitamins, ceramides, sunscreens, surfactants, spreading agents, wetting agents, dispersants, antifoams, neutralizing agents, stabilizers, polymers and in particular liposoluble film-forming polymers, and mixtures thereof. Needless to say, those skilled in the art will take care to select this or these optional additional compound(s) and/or the amounts thereof so that the advantageous properties of the composition for the use according to the invention are not, or not substantially, adversely affected by the envisaged addition.

The compositions according to the invention may be in any common acceptable form for a cosmetic or dermatological composition. Those skilled in the art may select the appropriate galenical form, and also the method for preparing it, on the basis of their general knowledge, taking into account both the nature of the constituents used, in particular their solubility in the support, and also the intended use of the composition.

The invention is illustrated in greater detail in the following examples.

Preparation examples The information regarding the various starting materials used in the examples that follow are summarized in the following table.

INCI name Supplier Trade name

CAVAMAX W7 FOOD β-cyclodextrin WACKER

GRADE®

CAVAMAX W6 FOOD a-cyclodextrin WACKER

GRADE®

CAVAMAX W8 PHARMA γ-cyclodextrin WACKER

GRADE®

Hydroxypropylcellulose 80K ASHLAND KLUCEL®

ALDRICH M625®

Maleic anhydride

CITRIC ACID

Citric acid DSM

MONOHYDRATE

Sodium dihydrogen SODIUM DIHYDROGEN

MERCK

phosphate PHOSPHATE DEHYDRATE, (RECTAPUR®)

Glycerol ALDRICH Glycerol

1 ) Synthesis of cyclodextrin polycondensates

Example 1a

The β-cyclodextrin polycondensate 1 a was obtained after extrusion of the β-cyclodextrin (CD) in the presence of hydroxypropylcellulose (HPC), citric acid and sodium dihydrogen phosphate (DHPS). The proportions of each constituent are indicated as percentages by weight below:

According to this preparation mode, all the ingredients which are part of the composition for obtaining the polycondensate 1 a were incorporated at the same time in the extrusion tool (Clextral BC 21 twin-screw extruder) at a temperature of 170°C.

The extrusion conditions are summarized hereinafter:

After milling, the polycondensate 1 a was obtained in the form of a cream-coloured powder with an average particle size of 10 μηη.

Protocol for measuring the degree of swelling in water:

2 g of milled cyclodextrin polycondensate 1 a were suspended in 20 g of demineralized water with light stirring for 24 h at ambient temperature. The suspension was centrifuged in order to separate the supernatant and the solids content was determined on the centrifugate using a thermobalance. The % degree of swelling was obtained by calculating the evaporated weight/dry weight ratio x 100.

The cyclodextrin polycondensate 1 a has an acid number of 150 mg of potassium hydroxide per g of polycondensate and a degree of swelling in water of 805%.

5

Examples 1 b, 2a, 2b and 2c

The following cyclodextrin polycondensates (composition and synthesis conditions) were synthesized according to the same process: the proportions of each constituent are 10 indicated as percentages by weight hereinafter:

The extrusion conditions, the acid number of the cyclodextrin polycondensates obtained and also their degree of swelling in water, measured according to the same conditions as Example 1 a, are summarized hereinafter.

Cyclodextrin Temperature Extrusion Extrusion Acid Degree polycondensates fC) rate (rpm) flow rate number of

(kg/h) swelling in water

1 b 170 1 10 3 161 740%

2a 180 1 10 3 127 520%

2b 175 130 3 130 440%

2c 180 1 10 3 128 530% Comparative example A of cyclodextrin polycondensate synthesis according to the process of patent EP1165621 B1

1 litre of demineralized water, 50 g of sodium dihydrogen phosphate NaH ₂ P0 _4, 500 g of citric acid monohydrate and 1 kg of β-cyclodextrin were placed in a 2-litre round-bottomed flask. The reaction medium was stirred and heated to 60°C-70°C in order to completely dissolve the starting compounds. The solution obtained was transferred into a crystallizing dish, the size of which is chosen so as to obtain a liquid height of approximately 6 cm. The crystallizing dish was placed in an oven heated at 100°C for 80 h (a soft gel was obtained). The temperature was then increased to 140°C for 4 h and then allowed to return to ambient temperature. The solid obtained was detached from the crystallizing dish and then finely milled using a knife mill of coffee mill type. It was analyzed by 2D DOSY NMR which made it possible to demonstrate the covalent grafting of the citric acid onto the β-cyclodextrin so as to form an oligomer, the diffusion coefficient of which is 173 μπ"ΐ ² /8, which corresponds to a molecular weight estimated at approximately 3800 g/mol. Its acid number is 195 mg of potassium hydroxide per g of polycondensate and its degree of swelling in water is 0% since it is entirely soluble at ambient temperature (solubility greater than 30%). Encapsulation of a fragrancing substance and time of release

The encapsulation properties of the β-cyclodextrin polycondensate 1 a were measured and compared with β-cyclodextrin alone, but also

- with the β-cyclodextrin polycondensate of Comparative Example A as described above, and

- with the β-cyclodextrin polycondensate crosslinked with epichlorohydrin containing 54% of CD sold by Cyclolab under the reference CY-2009® (Comparative Example B). 5 g of dihydromyrcenol ingredient (fragrance) were added to 1 g of tested compound, and then the mixture was left under light stirring for 24 hours. After centrifugation to remove the fragrance not impregnated in the matrix of each tested compound and air-drying at ambient temperature in a dry atmosphere for 24 h, the impregnated compound was heated at 150°C using a thermobalance, also known as a halogen desiccator (Mettler Toledo HG63), until the weight was constant. The amount of dihydromyrcenol encapsulated in the matrix of each tested polymer was thus measured.

An amount of between 0.5 g and 1 g of impregnated compound was deposited on the dish and then the heating was begun, with the weight loss being recorded every 2 minutes. When the weight was constant, the apparatus automatically stopped the heating and produced the following data: initial weight, final weight, % solids content at 2 minute intervals, total duration of evaporation. The amount of perfumery ingredient released and the time necessary for the release thereof was subsequently measured. The results of dihydromyrcenol encapsulation according to the protocol described previously are summarized in the table hereinbelow:

If the amount of fragrance released from the compound by addition of water (2 ml per g of impregnated compound) is quantified, after 48 h, an identical result is obtained.

It was observed that the β-cyclodextrin polycondensate 1 a according to the invention exhibits a level of fragrance encapsulation which is 3.7 times greater than that of β-cyclodextrin, than that of the comparative β-cyclodextrin polycondensate A and than that of the comparative β-cyclodextrin polycondensate B.

It was observed that the β-cyclodextrin polycondensate 1 a according to the invention results in a longer fragrance release time than that obtained with β-cyclodextrin, than that obtained with the comparative β-cyclodextrin polycondensate A and than that obtained with the comparative β-cyclodextrin polycondensate B. Com parative tests between a cycl odextri n polycon densate accord i ng to the i nventi on and cycl odextri n polycondensates accord i ng to the app l i cati on WO01 /48025 Examples 1 c, 3a, 3b

The following cyclodextrin polycondensates (composition and synthesis conditions) were synthesized according to the same process: the proportions of each constituent are indicated as percentages by weight hereinafter:

The extrusion conditions are summarized hereinafter.

Encapsulation of a fragrancing substance and time for releasing

The encapsulation properties of the β-cyclodextrin polycondensate 1 c were measured and compared with the β-cyclodextrin polycondensate of Comparative Example 3a as described above.

5 g of dihydromyrcenol ingredient (fragrance) were added to 1 g of tested compound, and then the mixture was left under light stirring for 24 hours. After centrifugation to remove the fragrance not impregnated in the matrix of each tested compound and air-drying at ambient temperature in a dry atmosphere for 24 h, the impregnated compound was heated at 150°C using a thermobalance, also known as a halogen desiccator (Mettler Toledo HG63), until the weight was constant. The amount of dihydromyrcenol encapsulated in the matrix of each tested polymer was thus measured.

An amount of between 0.5 g and 1 g of impregnated compound was deposited on the dish and then the heating was begun, with the weight loss being recorded every 2 minutes. When the weight was constant, the apparatus automatically stopped the heating and produced the following data: initial weight, final weight, % solids content at 2 minute intervals, total duration of evaporation. The amount of perfumery ingredient released and the time necessary for the release thereof was subsequently measured. The results of dihydromyrcenol encapsulation according to the protocol described previously are summarized in the table hereinbelow:

If the amount of fragrance released from the compound by addition of water (2 ml per g of impregnated compound) is quantified, after 48 h, an identical result is obtained.

It was observed that the β-cyclodextrin polycondensate 1 c according to the invention exhibits a level of fragrance encapsulation which is 3.4 times greater than that of the comparative β-cyclodextrin polycondensate 3a.

It was observed that the β-cyclodextrin polycondensate 1 a according to the invention results in a longer fragrance release time than that obtained with the comparative β- cyclodextrin polycondensate 3a.