FR2910302A1 - Bleaching keratin fibers, especially human hair, by applying silicone-forming reactive components, oxidizing agent and optionally organic solvent - Google Patents

Abstract

A method for bleaching keratin fibers comprises applying: (a) compound(s) (X) and compound(s) (Y) (at least one of which is a silicone), which when contacted react with each other by hydrosilylation, by condensation or by crosslinking in presence of peroxide; (b) oxidizing agent(s); and (c) optionally organic solvent(s). Independent claims are included for: (1) the use of the components (a), (b) and optionally (c) (and optionally also alkali) for bleaching keratin fibers; (2) a bleaching kit containing at least two separately stored compositions, which jointly contain the components (a), (b) and optionally (c) and optionally alkali; and (3) a composition for bleaching keratin fibers, containing the components (a), (b) and optionally (c) (and optionally also alkali).

Description

1 DECOLORATION PROCESS USING X-COMPOUND AND Y-COMPOUND

  The subject of the present invention is a process for bleaching keratinous fibers, and in particular human keratinous fibers such as the hair, comprising applying at least two keratin fibers to the hair. compounds X and Y, able to react together, at least one of these compounds being silicone, at least one oxidizing agent, and optionally at least one organic solvent.

  It is known to decolorize keratinous fibers, and in particular human keratinous fibers such as the hair, with bleaching compositions containing one or more oxidizing agents. Among the oxidizing agents conventionally used, mention may be made of hydrogen peroxide, compounds capable of producing hydrogen peroxide by hydrolysis, such as urea peroxide, or persalts such as perborates, percarbonates and persulfates. hydrogen peroxide and persulfates being particularly preferred. The bleaching compositions are mainly in the form of anhydrous products, powders or creams, containing alkaline compounds such as amines or alkali silicates, and a peroxygenated reagent such as persulfates, perborates or percarbonates, ammonium or alkali metals, which are diluted at the time of use with an aqueous composition of hydrogen peroxide. The bleaching compositions may also result from mixing, at the time of use, an anhydrous powder containing the peroxygenated reagent with an aqueous composition containing the alkaline compounds and another aqueous composition containing the hydrogen peroxide. The bleaching compositions are also in the form of thickened aqueous compositions of hydrogen peroxide.

  The use of such oxidizing agents has the disadvantage of degrading the keratinous fibers and altering their cosmetic properties to lead, for example, to a difficult disentangling, an unpleasant touch or rough and dull hair.  It is also known from patent application FR 2 833 489 hair treatment compositions from compositions comprising electrophilic monomers.  Such a composition makes it possible to obtain perfectly sheathed hair.  However, these sheathings do not give full satisfaction in terms of remanence, especially sebum.  Documents WO 01/96450, GB 2 407 496 and EP 465 744 describe the use of particular reactive silicones for producing film on the skin.  WO 01/96450 and GB 2 407 496 disclose a one-part formulation which comprises a polysiloxane having trialkoxyalkylsilyl end groups, a catalyst, a solvent and optionally an alkoxysilane and fillers.  These compositions make it possible to obtain a film on the skin by condensation.  EP 465 744 describes the use of polysiloxane with unsaturated aliphatic groups for producing medical devices for topical use.  The object of the present invention is to provide a process for bleaching keratinous fibers which does not have the drawbacks of the known processes of the prior art, in particular a process for bleaching keratinous fibers which makes it possible to obtain an effect of lightening keratin fibers without degrading or limiting their degradation and without altering their cosmetic properties.  This object is achieved with the present invention, which relates to a process for bleaching keratinous fibers, comprising the application to the keratin fibers of: at least one compound X and at least one compound Y, at least one of the compounds X and Y being a silicone compound, said compounds X and Y being capable of reacting together by a reaction of hydrosilylation, condensation, or crosslinking in the presence of peroxide, when they are brought into contact; at least one oxidizing agent; and optionally at least one organic solvent.  The method according to the present invention makes it possible to obtain a lightening effect of keratin fibers without degrading them or by limiting their degradation and without altering their cosmetic properties.  The compounds X and Y are capable of reacting together on the keratinous fibers so as to form a remanent and cosmetic coating on the surface of the keratinous fibers.  The hair has good cosmetic properties and can be easily capped.  The subject of the present invention is also the use for the bleaching of keratinous fibers of at least two compounds X and Y, able to react together, at least one of these compounds being silicone, of at least one oxidizing agent, and optionally at least one organic solvent.  The present invention also relates to a kit for the bleaching of keratinous fibers comprising at least two compositions packaged separately, the kit comprising at least two compounds X and Y, able to react together, at least one of these compounds being silicone at least one oxidizing agent, and optionally at least one organic solvent.  The present invention also relates to a composition for the bleaching of keratinous fibers comprising at least two compounds X and Y, capable of reacting together, at least one of these compounds being silicone, at least two different oxidizing agents. on the other, and optionally at least one organic solvent.  Before their application to the keratinous fibers, the compound (s) X, the compound (s) Y, the oxidizing agent (s) and any organic solvent (s) may be present in several distinct compositions containing the compound (s) X, the or the compounds Y, the oxidizing agent (s) and the optional organic solvent or solvents, alone or as a mixture, or in a single composition containing the compound (s) X, the compound (s) Y, the oxidizing agent (s) and the optional organic solvent (s).  The different compositions used in the process according to the invention can be applied to dry or wet hair.  Rinsing and / or shampooing and / or drying may be performed between each application.  Keratin fibers can be dried in the open air, using a hair dryer or a helmet.  The flat or round tongs of an iron can be used after a pre-drying of the keratinous fibers.  Compounds X and Y Silicone compound is understood to mean a compound comprising at least two organosiloxane units.  According to a particular embodiment, the compounds X 5 and the compounds Y are silicone.  Compounds X and Y may be amino or non-amino.  They may include polar groups which may be selected from the following groups: COOH; -COO-; -COO-; -OH ; -NH2; -NH-; -NR-; -S03H; -S03-; -OCH2CH2-; -O-CH 2 CH 2 CH 2 -; -O-CH 2 CH (CH 3) -; -NR3 +; -SH; - NO2; -1; -Cl; -Br; -CN; -PO43-; -CONH-; -CONR-; -CONH2; -CSNH-; -SO2-; - 10 SO-; -SO2NH-; -NHCO-; -NHSO2-; -NHCOO-; -OCONH-; -NHCSO-; - OCSNH-; R representing an alkyl group.  According to another embodiment, at least one of the compounds X and Y is a polymer whose main chain is formed mainly of organosiloxane units.  Among the silicone compounds mentioned below, some may have both film-forming and adhesive properties, for example according to their proportion of silicone or depending on whether they are used in admixture with a particular additive.  It is therefore possible to modulate the film-forming properties or the adhesive properties of such compounds according to the intended use, this is particularly the case for reactive elastomeric silicones called "room temperature vulcanization".  Compounds X and Y may react together at a temperature varying between room temperature and 180 C.  Advantageously, compounds X and Y are capable of reacting together at ambient temperature (20 ° C.) and atmospheric pressure, advantageously in the presence of a catalyst, by a hydrosilylation reaction, or a condensation reaction, or a reaction of crosslinking in the presence of a peroxide.  1 / Compounds X and Y Which Can Be Reacted by Hydrosilvlation According to one embodiment, compounds X and Y are capable of reacting by hydrosilylation, this reaction being simplified in the following way: ## STR1 ## with W representing a carbon and / or silicone chain containing one or more unsaturated aliphatic groups.  In this case, the compound X may be chosen from silicone compounds comprising at least two unsaturated aliphatic groups.  By way of example, the compound X may comprise a silicone main chain whose unsaturated aliphatic groups are pendant to the main chain (lateral group) or located at the ends of the main chain of the compound (terminal group).  In the remainder of the description, these particular compounds will be called polyorganosiloxanes with unsaturated aliphatic groups.  According to one embodiment, the compound X is chosen from polyorganosiloxanes comprising at least two unsaturated aliphatic groups, for example two or three vinyl or allylic groups, each bonded to a silicon atom.  According to an advantageous embodiment, the compound X is chosen from polyorganosiloxanes comprising siloxane units of formula: R.  In which: R represents a linear or cyclic monovalent hydrocarbon group comprising from 1 to 30 carbon atoms, preferably from 1 to 20, and more preferably from 1 to 10 carbon atoms; such as, for example, a short-chain alkyl radical comprising, for example, from 1 to 10 carbon atoms, in particular a methyl radical or else a phenyl group, preferably a methyl radical; m is 1 or 2, and R 'represents: an unsaturated aliphatic hydrocarbon group comprising from 2 to 10, preferably from 2 to 5 carbon atoms, for example a vinyl group or a group -R "-CH = CHR wherein R "is a divalent aliphatic hydrocarbon-based chain having 1 to 8 carbon atoms, attached to the silicon atom and R" "is a hydrogen atom or an alkyl radical comprising 1 to 4 carbon atoms, preferably a hydrogen atom; mention may be made, as group R ', of the vinyl and allyl groups and their mixtures; or an unsaturated cyclic hydrocarbon group comprising from 5 to 8 carbon atoms such as, for example, a cyclohexenyl group.  Preferably R 'is an unsaturated aliphatic hydrocarbon group, preferably a vinyl group.  According to a particular embodiment, the polyorganosiloxane also comprises units of formula: R (II) in which R is a group as defined above, and n is equal to 1, 2 or 3.  According to one variant, the compound X may be a silicone resin comprising at least two ethylenic unsaturations, said resin being capable of reacting with the compound Y by hydrosilylation.  Mention may be made, for example, of resins of MQ or MT type bearing itself unsaturated reactive ends -CH = CH2.  These resins are crosslinked organosiloxane polymers.  The nomenclature of silicone resins is known as "MDTQ", the resin being described according to the different siloxane monomeric units it comprises, each of the letters "MDTQ" characterizing a type of unit.  The letter M represents the monofunctional unit of formula (CH 3) 3 SiO 12, the silicon atom being connected to a single oxygen atom in the polymer comprising this unit.  The letter D means a difunctional unit (CH3) 2SiO212 in which the silicon atom is connected to two oxygen atoms.  The letter T represents a trifunctional unit of formula (CH3) SiO312.  In the units M, D and T defined above, at least one of the methyl groups may be substituted with a group R other than the methyl group such as a hydrocarbon radical (in particular alkyl) having from 2 to 10 carbon atoms or a group phenyl or else a hydroxyl group.  Finally, the letter Q signifies a tetrafunctional SiO412 unit in which the silicon atom is bonded to four hydrogen atoms, themselves linked to the remainder of the polymer.  Examples of such resins include MT silicone resins such as poly (phenyl-vinylsilsesquioxane) such as those sold under the reference SST-3PV1 by Gelest.  Preferably, the compounds X comprise from 0.01 to 1% by weight of unsaturated aliphatic groups.  Advantageously, the compound X is chosen from polyorganopolysiloxanes, in particular those comprising the siloxane (I) and optionally (II) units described above.  The compound Y preferably comprises at least two free Si-H groups (hydrogenosilane groups).  The compound Y may advantageously be chosen from organosiloxanes comprising at least one alkylhydrogenosiloxane unit of the following formula:  Wherein R represents a monovalent hydrocarbon group, linear or cyclic, comprising from 1 to 30 carbon atoms, for example an alkyl radical having from 1 to 30 carbon atoms, preferably from 1 to 30 carbon atoms; at 20 and better still 1 to 10 carbon atoms, in particular a methyl radical, or else a phenyl group and p is equal to 1 or 2.  R is preferably a hydrocarbon group, preferably methyl.  These organosiloxane compounds Y with alkylhydrogenosiloxane units may further comprise units of formula: as defined above.  The compound Y may be a silicone resin comprising at least one unit selected from the units M, D, T, Q as defined above and comprising. At least one Si-H group such as the poly (methyl-hydridosilsesquioxane) sold under the reference SST-3MH1. 1 by the company Gelest.  Preferably, these organosiloxane compounds Y comprise from 0.5 to 2.5% by weight of Si-H groups.  Advantageously, the radicals R represent a methyl group in formulas (I), (II), (III) above.  Preferably, these organosiloxanes Y comprise terminal groups of formula (CH 3) 3 SiO 12.  Advantageously, the organosiloxanes Y comprise at least two alkylhydrogensiloxane units of formula (H3C) (H) SiO and optionally comprise (H3C) 2SiO units.  Such organosiloxane compounds Y having hydrogenosilane groups are described, for example, in document EP 0465744.  According to one variant, the compound X is chosen from oligomers or organic polymers (by organic means compounds whose main chain is non-silicone, preferably compounds containing no silicon atoms) or from polymers or hybrid organic / silicone oligomers, said oligomers or polymers bearing at least 2 reactive unsaturated aliphatic groups, the compound Y being selected from the above-mentioned hydrogen siloxanes.  Compound X, of organic nature, can then be chosen from vinyl, (meth) acrylic polymers or oligomers, polyesters, polyurethanes and / or polyureas, polyethers, perfluoropolyethers, polyolefins such as polybutene, polyisobutylene, dendrimers or organic hyperbranched polymers, or mixtures thereof.  In particular, the organic polymer or the organic part of the hybrid polymer may be chosen from the following polymers: a) polyesters with ethylenic unsaturation (s): This is a group of polymers of the polyester type having at least 2 ethylenic double bonds, randomly distributed in the main chain of the polymer.  These unsaturated polyesters are obtained by polycondensation of a mixture: linear or branched or cycloaliphatic aliphatic dicarboxylic acids containing in particular from 3 to 50 carbon atoms, preferably from 3 to 20 and better still from 3 to 10 carbon atoms, such as adipic acid or sebacic acid, aromatic dicarboxylic acids having in particular 8 to 50 carbon atoms, preferably 8 to 20 and better still 8 to 14 carbon atoms, such as phthalic acids, especially terephthalic acid, and / or dicarboxylic acids derived from dimers of ethylenically unsaturated fatty acids, such as the oleic or linoleic acid dimers described in application EP-A-959 066 (paragraph [0021)) marketed under the Pripol denominations by Unichema or Empol by Henkel, all these diacids to be free of polymerizable ethylenic double bonds; of linear or branched or cycloaliphatic aliphatic diols comprising in particular from 2 to 50 carbon atoms, preferably from 2 to 20 and better still from 2 to 10 carbon atoms, such as ethylene glycol, diethylene glycol, propylene glycol, and the like; , 4-butanediol or cyclohexanedimethanol, aromatic diols having 6 to 50 carbon atoms, preferably 6 to 20 and more preferably 6 to 15 carbon atoms such as bisphenol A and bisphenol B, and / or dimers diols from the reduction of fatty acid dimers as defined above; and one or more dicarboxylic acids or their anhydrides containing at least one polymerizable ethylenic double bond and having from 3 to 50 carbon atoms, preferably from 3 to 20 and better still from 3 to 10 carbon atoms, such as maleic acid, fumaric acid or itaconic acid.  B) polyesters with (meth) acrylate groups and / or terminal: This is a group of polymers of the polyester type obtained by polycondensation of a mixture of: linear aliphatic dicarboxylic acids or branched or cycloaliphatic comprising in particular from 3 to 50 carbon atoms, preferably from 3 to 20 and more preferably from 3 to 10 carbon atoms, such as adipic acid or sebacic acid, of aromatic dicarboxylic acids having especially from 8 to 50 carbon atoms; preferably 8 to 20 and more preferably 8 to 14 carbon atoms, such as phthalic acids, especially terephthalic acid, and / or dicarboxylic acids derived from ethylenically unsaturated fatty acid dimers such as dimers of the oleic or linoleic acids described in application EP-A-959 066 (paragraph [0021]) marketed under the names Pripol by the company Unichema or Empol by Henkel, all these diacids of to be free of polymerizable ethylenic double bonds; of linear or branched or cycloaliphatic aliphatic diols comprising in particular from 2 to 50 carbon atoms, preferably from 2 to 20 and better still from 2 to 10 carbon atoms, such as ethylene glycol, diethylene glycol, propylene glycol, 1, 4-butanediol or cyclohexanedimethanol, aromatic diols having 6 to 50 carbon atoms, preferably 6 to 20 and more preferably 6 to 15 carbon atoms such as bisphenol A and bisphenol B; and at least one (meth) acrylic acid ester and a diol or polyol having from 2 to 20 carbon atoms, preferably from 2 to 6 carbon atoms, such as the (meth) acrylate of 2 hydroxyethyl, 2-hydroxypropyl (meth) acrylate and glycerol methacrylate.  These polyesters differ from those described above under point a) in that the ethylenic double bonds are not located in the main chain but on side groups or at the end of the chains.  These ethylenic double bonds are those of the (meth) acrylate groups present in the polymer.  Such polyesters are sold, for example, by the company UCB under the names EBECRYL (EBECRYL 450: molar mass 1600, on average 6 acrylate functions per molecule, EBECRYL 652: molar mass 1500, on average 6 acrylate functions per molecule, EBECRYL 800: mass Molar 780, on average 4 acrylate functions per molecule, EBECRYL 810: molar mass 1000, on average 4 acrylate functions per molecule, EBECRYL 50,000: molar mass 1500, on average 6 acrylate functions per molecule).  c) polyurethanes and / or polyureas containing (meth) acrylate groups, obtained by polycondensation: cycloaliphatic and / or aromatic aliphatic diisocyanates, triisocyanates and / or polyisocyanates having in particular from 4 to 50, preferably from 4 to 30 carbon atoms, carbon, such as hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate or isocyanurates of the formula: ## STR5 ## resulting from the trimerization of 3 molecules of OCN-R-CNO diisocyanates where R is a linear, branched or cyclic hydrocarbon radical having from 2 to 30 carbon atoms; 5 - polyols, especially diols, free of polymerizable ethylenic unsaturations, such as 1,4-butanediol, ethylene glycol or trimethylolpropane, and / or polyamines, especially diamines, aliphatic, cycloaliphatic and / or aromatic having in particular from 3 to 50 carbon atoms, such as ethylenediamine or hexamethylenediamine; and at least one (meth) acrylic acid ester and a diol or polyol having 2 to 20 carbon atoms, preferably 2 to 6 carbon atoms, such as (meth) acrylate, 2-hydroxyethyl, 2-hydroxypropyl (meth) acrylate and glycerol methacrylate.  Such acrylate-containing polyurethanes / polyureas are commercially available for example under the name SR 368 (tris (2-hydroxyethyl) isocyanurate-triacrylate) or CRAYNOR 435 by the company CRAY VALLEY, or under the name EBECRYL by the company UCB (EBECRYL 210 : 1500 molar mass, 2 acrylate functions per molecule, EBECRYL 230: 5000 molar mass, 2 acrylate functions per molecule, EBECRYL 270: 1500 molar mass, 2 acrylate functions per molecule, EBECRYL 8402: 1000 molar mass, 2 acrylate functions per molecule , EBECRYL 8804: Molar mass 1300, 2 acrylate functions per molecule, EBECRYL 220: Molar mass 1000, 6 acrylate functions per molecule, EBECRYL 2220: Molar mass 1200, 6 acrylate functions per molecule, EBECRYL 1290: Molar mass 1000, 6 25 functions acrylate per molecule, EBECRYL 800: 800 molar mass, 6 acrylate functions per molecule).  Mention may also be made of the water-soluble aliphatic diacrylate polyurethanes sold under the names EBECRYL 2000, EBECRYL 2001 and EBECRYL 2002, and the aqueous dispersion diacrylate polyurethanes sold under the trade names IRR 390, IRR 400 and IRR 422 IRR 424 by the company UCB. .  d) polyethers with (meth) acrylate groups obtained by esterification, with (meth) acrylic acid, of terminal hydroxyl groups of homopolymers or copolymers of C 1 -C 4 alkylene glycols, such as polyethylene glycol, polypropylene glycol, copolymers of ethylene oxide and propylene oxide preferably having a weight average molecular weight of less than 10,000, polyethoxylated or polypropoxylated trimethylolpropane.  Suitable molar mass polyoxyethylenes (meth) acrylates are commercially available, for example, under the names SR 259, SR 344, SR 610, SR 210, SR 603 and SR 252 by the company CRAY VALLEY or under the name EBECRYL 11 by UCB.  Polyethoxylated trimethylolpropane triacrylates are commercially available, for example, under the names SR 454, SR 498, SR 502, SR 9035, SR 415 by the company Cray Valley or under the name EBECRYL 160 by the company UCB.  Polypropoxylated trimethylolpropane triacrylates are sold, for example, under the names SR 492 and SR 501 by the company Cray Valley.  e) epoxyacrylates obtained by reaction between: at least one diepoxide chosen for example from: (i) diglycidyl ether of bisphenol A, (ii) a diepoxy resin resulting from the reaction between bisphenol A diglycidyl ether and epichlorohydrin, (iii) an α,--diepoxy terminated epoxy ester resin resulting from the condensation of a dicarboxylic acid having from 3 to 50 carbon atoms with a stoichiometric excess of (i) and / or (ii), (iv) an epoxy ether resin having α,--diepoxy ends resulting from the condensation of a diol having from 3 to 50 carbon atoms with a stoichiometric excess of (i) and / or (ii), (v) natural oils or synthetic containing at least 2 epoxide groups, such as epoxidized soybean oil, epoxidized linseed oil and epoxidized vernonia oil, (vi) a phenol-formaldehyde polycondensate (Novolac resin), whose ends and / or the side groups have been epoxidized, and 2910302 One or more carboxylic acids or polycarboxylic acids containing at least one ethylenic double bond in a, of the carboxylic group such as (meth) acrylic acid or crotonic acid or esters of (meth) acrylic acid and a diol or polyol having 2 to 20 carbon atoms, preferably 2 to 6 carbon atoms such as 2-hydroxyethyl (meth) acrylate.  Such polymers are sold, for example under the names SR 349, SR 601, CD 541, SR 602, SR 9036, SR 348, CD 540, SR 480, CD 9038 by the company Cray Valley, under the names EBECRYL 10 600 and EBECRYL. 609, EBECRYL 150, EBECRYL 860, EBECRYL 3702 by the company UCB and under the names PHOTOMER 3005 and PHOTOMER 3082 by the company HENKEL.  f) poly (meth) acrylates of (C 1-50) alkyl, said alkyl being linear, branched or cyclic, comprising at least two functions with ethylenic double bond borne by the side and / or terminal hydrocarbon chains.  Such copolymers are sold for example under the names IRR 375, OTA 480 and EBECRYL 2047 by the company UCB.  g) polyolefins such as polybutene, polyisobutylene.  h) perfluoropolyethers containing acrylate groups obtained by esterification, for example with (meth) acrylic acid, of perfluoropolyethers bearing lateral and / or terminal hydroxyl groups.  Such perfluoropolyethers 1, 4-diols are described in particular in EP-A-1057849 and are sold by the company AUSIMONT under the name FOMBLIN Z DIOL.  I) dendrimers and hyperbranched polymers bearing (meth) acrylate or (meth) acrylamide end groups respectively obtained by esterification or amidification of dendrimers and hyperramified polymers with hydroxyl or amino terminal functions, with (meth) acrylic acid.  Dendrimers (from the Greek dendron = tree) are "tree" polymeric molecules, that is to say, highly branched molecules invented by D.  AT.  Tomalia and his team in the early 90s (Donald A.  Tomalia et al. , Angewandte Chemie, Int.  Engl.  Ed. , flight.  29, No. 2, pp. 138-175).  These are structures built around a generally versatile central pattern.  Around this central motif are chained, according to a perfectly determined structure, branched chain extension units thus giving rise to symmetrical, monodisperse macromolecules having a well-defined chemical and stereochemical structure.  Dendrimers of the polyamidoamine type are marketed for example under the name STARBUST by the company DENDRITECH.  The hyperbranched polymers are polycondensates, generally of polyester, polyamide or polyethyleneamine type, obtained from multifunctional monomers, which have a tree structure similar to that of the dendrimers but much less regular than this one (see for example WOA-93/17060). and WO 96/12754).  The company PERSTORP markets under the name BOLTORN hyperbranched polyesters.  Under the COMBURST name of the company DENDRITECH are hyperbranched polyethyleneamines.  Hyperramified poly (esteramide) with hydroxyl ends are marketed by DSM under the name HYBRANE.  These dendrimers and hyperbranched polymers esterified or amidified by acrylic and / or methacrylic acid are distinguished from the polymers described under points a) to h) above by the very large number of ethylenic double bonds present.  This high functionality, most often greater than 5, makes them particularly useful by allowing them to act as a "crosslinking node", that is to say a multiple crosslinking site.  These dendritic and hyperbranched polymers can thus be used in combination with one or more of the polymers and / or oligomers a) to h) above.  The additional reactive compounds According to one embodiment, at least one of the compositions applied to the keratinous fibers or an additional composition may further comprise an additional reactive compound such as: the organic or inorganic particles comprising on their surface at least Examples of unsaturated aliphatic groups that may be mentioned are surface-treated silicas, for example silicone-containing compounds containing vinyl groups such as, for example, cyclotetramethyltetravinylsiloxane-treated silica, and silazane compounds such as hexamethyldisilazane.  Catalyst The hydrosilylation reaction is advantageously carried out in the presence of a catalyst which may be present in at least one of the compositions applied to the keratinous fibers or a further composition, the catalyst being preferably platinum-based. or tin.  There may be mentioned, for example, platinum catalysts deposited on a silica gel or charcoal powder (charcoal) support, platinum chloride, platinum and chloroplatinic acid salts.  The chloroplatinic acids are preferably used in hexahydrate or anhydrous form, which is easily dispersible in organosilicone media.  There may also be mentioned platinum complexes such as those based on chloroplatinic acid hexahydrate and divinyl tetramethyldisiloxane.  The catalyst may be present in the composition comprising it in a content ranging from 0.0001% to 20% by weight relative to the total weight of the composition.  It is also possible to introduce into at least one of the compositions applied to the keratinous fibers or a further composition of the polymerization inhibitors or retarders, and more particularly catalyst inhibitors, in order to increase the stability of the composition over time. or delaying the polymerization.  In a nonlimiting manner, mention may be made of cyclic polymethylvinylsiloxanes, and in particular tetravinyl tetramethylcyclotetrasiloxane, and acetylenic alcohols, which are preferably volatile, such as methylisobutynol.  The presence of ionic salts, such as sodium acetate, in at least one of the compositions applied to the keratinous fibers or additional composition may influence the rate of polymerization of the compounds.  Advantageously, the compounds X and Y are chosen from silicone compounds capable of reacting by hydrosilylation; in particular, compound X is chosen from polyorganosiloxanes comprising units of formula (I) described above and compound Y is chosen from organosiloxanes comprising alkylhydrogensiloxane units of formula (III) described above.  According to one particular embodiment, the compound X is a polydimethylsiloxane with terminal vinyl groups, and the compound Y is methylhydrogensiloxane.  By way of examples of a combination of such compounds X and Y reacting by hydrosilylation, mention may be made of the following references proposed by the Dow Corning company: DC 7-9800 Soft Skin Adhesive parts A & B, as well as the mixtures A and following B prepared by Dow Corning: MIXTURE A: Ingredient (INCI name) N CAS Content Function (wt%) Dimethyl Siloxane, 68083-55-95 Dimethylvinylsiloxy-terminated Polymer 19-2 Silica Silylate 68909- 10-40 Charge 20- 6 1,3-Diethenyl-1,1,3,3- 68478- Trace Catalyst Tetramethyldisiloxane 92-2 complexes Tetramethyldivinyldisiloxane 2627-95-0.1-1 Polymer 4 MIXTURE B: Ingredient (INCI name) N CAS Level Function (% by weight) Dimethyl Siloxane, 68083-19-55-95 Polymer Dimethylvinylsiloxy-2-terminated Silica Silylate 68909-20- 10-40 Charge 6 Dimethyl, Methylhydrogen 68037-59- 1-10 Polymer Siloxane, trimethylsiloxy-2 terminated 2910302 17 2 / Compounds X and Y likely to react by condensation According to this embodiment X and Y compounds are capable of reacting by condensation, either in the presence of water (hydrolysis) by reaction of two compounds bearing alkoxysilane groups, or by direct condensation by reaction of a group-carrying compound (s). ) alkoxysilane (s) and a silanol group (s) carrier compound or by reaction of 2 silanol group (s) bearing compounds.  When the condensation is carried out in the presence of water, this may be in particular the ambient humidity, the residual water of the keratin fibers, or the water supplied by an external source, for example by prior wetting of the keratinous fibers. (for example by a fogger).  In this condensation reaction mode, the compounds X and Y, which are identical or different, may therefore be chosen from silicone compounds whose main chain comprises at least two alkoxysilane groups and / or at least two silanol groups (Si-OH) , side and / or at the end of the chain.  According to an advantageous embodiment, the compounds X and / or Y are chosen from polyorganosiloxanes comprising at least two alkoxysilane groups.  By alkoxysilane group is meant a group comprising at least one -Si-OR moiety, where R is an alkyl group having 1 to 6 carbon atoms.  The compounds X and Y are especially chosen from polyorganosiloxanes comprising alkoxysilane end groups, more specifically those which comprise at least 2 terminal alkoxysilane groups, preferably terminal trialkoxysilanes.  These compounds X and / or Y preferably comprise, in a majority manner, units of formula: (IV) in which R 9 independently represents a radical chosen from alkyl groups comprising from 1 to 6 carbon atoms, phenyl and fluorinated alkyl groups , and s is 0, 1, 2 or 3.  Preferably, R 9 independently represents an alkyl group having 1 to 6 carbon atoms.  Alkyl groups that may be mentioned include methyl, propyl, butyl, hexyl and mixtures thereof, preferably methyl or ethyl.  As the fluoroalkyl group, 3,3,3-trifluoropropyl may be mentioned.  According to a particular embodiment, the compounds X and Y, which are identical or different, are polyorganosiloxanes comprising units of formula: ## STR2 ## in which R 9 is as described above, preferably R 9 is a methyl radical, and f is in particular as the polymer has a viscosity at 25 C ranging from 0.5 to 3000 Pa. s, preferably ranging from 5 to 150 Pa. s and / or f is in particular a number ranging from 2 to 5000, preferably from 3 to 3000, more preferably from 5 to 1000.  These X and Y polyorganosiloxane compounds comprise at least 2 terminal trialkoxysilane groups per polymer molecule, said groups having the following formula: 1 () '- (VI) in which: the R radicals independently represent a methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl or isobutyl group, preferably a methyl or ethyl group, R' is a methyl or ethyl group, x is equal to 0 or 1, preferably x is equal to 0, and Z is chosen from: divalent hydrocarbon groups not containing ethylenic unsaturation and comprising from 2 to 18 carbon atoms (groups alkylene), the combinations of divalent hydrocarbon radicals and siloxane segments of the following formula (IX): wherein R 9 is as described above, G is a divalent hydrocarbon radical having no ethylenic unsaturation and comprising 2 to 18 carbon atoms and c is an integer from 1 to 6.  Z and G may especially be chosen from alkylene groups such as ethylene, propylene, butylene, pentylene, hexylene, arylene groups such as phenylene.  Preferably, Z is an alkylene group, and better ethylene.  These polymers may have on average at least 1.2 trialkoxysilane end groups or terminal chains per molecule, and preferably on average at least 1.5 trialkoxysilane end groups per molecule.  Since these polymers may have at least 1.2 trialkoxysilane end groups per molecule, some may comprise other types of terminal groups such as terminal groups of formula CH 2 = CHSiR 92 - or of formula R 63 -Si--, in which R 9 is such as defined above and each R6 group is independently selected from R9 or vinyl groups.  Examples of such end groups include trimethoxysilane, triethoxysilane, vinyldimethoxysilane and vinylmethyloxyphenylsilane.  Such polymers are described in particular in US Pat. No. 3,175,993, US Pat. No. 4,772,675, US Pat. No. 4,871,827, US Pat. No. 4,888,380, US Pat. No. 4,898,910, US Pat. No. 4,906,719 and US Pat. No. 4,962,174, the contents of which are incorporated by reference. to the present application.  As compound X and / or Y, there may be mentioned in particular the polymer of formula: ## STR2 ## W) 3. ,. x Z (S Q) fS Z-Si OJ &).  x i (VII) wherein R, R ', R9, Z, x and f are as described above.  Compounds X and / or Y may also comprise a polymer mixture of formula (VII) above with polymers of formula (VIII) below: ## STR5 ## `R9 R R. wherein R, R ', R9, Z, x and f are as described above.  When the compound X and / or Y polyorganosiloxanes with alkoxysilane group (s) comprises such a mixture, the various polyorganosiloxanes are present in contents such that the terminal organosilyl chains represent less than 40%, preferably less than 25% in number of the terminal chains.  Particularly preferred compounds X and / or Y polyorganosiloxanes are those of formula (VII) described above.  Such X and / or Y compounds are described, for example, in WO 01/96450.  As indicated above, the compounds X and Y may be the same or different.  According to one variant, one of the two reactive compounds X or Y is of a silicone nature and the other is of organic nature.  For example, compound X is chosen from organic oligomers or polymers or oligomers or hybrid organic / silicone polymers, said polymers or oligomers comprising at least two alkoxysilane groups and Y is chosen from silicone compounds such as the polyorganosiloxanes described above. above.  In particular, the organic oligomers or polymers are chosen from vinyl, (meth) acrylic, polyester, polyamide, polyurethane and / or polyurea oligomers or polyethers, polyethers, polyolefins, perfluoropolyethers, dendrimers and organic hyperbranched polymers, and mixtures thereof. .  The organic polymers of vinyl or (meth) acrylic nature, bearing alkoxysilane side groups, may in particular be obtained by copolymerization of at least one vinylic or (meth) acrylic organic monomer with a (meth) acryloxypropyltrimethoxysilane, a vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, etc.  For example, mention may be made of the (meth) acrylic polymers described in the KUSABE document. M. Pitture e Verniei - European Coating; 12-B, pages 43-2910302, 49, 2005, and in particular the polyalkyl acrylates with alkoxysilane groups referenced MAX of Kaneka or those described in the publication of PROBSTER, M, Adhesion-Kleben & Dichten, 2004, 481 (1-2), pages 12-14.  The organic polymers resulting from a polycondensation or a polyaddition, such as polyesters, polyamides, polyurethanes and / or polyureas, polyethers, and bearing side and / or terminal alkylsilanes groups, may result for example from the reaction of an oligomeric prepolymer as described above with one of the following silane co-reactants bearing at least one alkoxysilane group: aminopropyltrimethoxysilane, aminopropyltriethoxysilane, aminoethylaminopropyltrimethoxysilane, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, epoxycyclohexylethyltrimethoxysilane, mercaptopropyltrimethoxysilane.  Examples of polyethers and polyisobutylenes with alkoxysilane groups are described in the KUSABE publication. Mr. Pitture e Verniei European Coating; 12-B, pp. 43-49, 2005.  As an example of polyurethanes with terminal alkoxysilane groups, mention may be made of those described in the document PROBSTER, M. , Adhesion-Kleben & Dichten, 2004, 481 (1-2), pages 12-14 or those described in the document LANDON, S. , Pitture e Verniei Vol.  73, No. 11, pages 18-24, 1997 or in the document HUANG, Mowo, Pitture e Verniei 20 vol.  5, 2000, pages 61-67, there may be mentioned polyurethanes alkoxysilane groups of OSI-WITCO-GE.  As compounds X and / or Y polyorganosiloxanes, mention may be made of resins of the MQ or MT type, itself bearing alkoxysilane and / or silanol ends, for instance the poly (isobutylsilsesquioxane) resins functionalized with silanol groups proposed under reference SSTS7C41 (3 Si-OH groups) by Gelest.  2a Additional reactive compounds At least one of the compositions

  applied to the keratin fibers or a further composition may further comprise an additional reactive compound comprising at least two alkoxysilane or silanol groups.  For example, one or more organic or inorganic particles comprising, on their surface, alkoxysilane and / or silanol groups, for example fillers surface-treated with such groups.  Catalyst The condensation reaction may be carried out in the presence of a metal-based catalyst which may be present in at least one of the compositions applied to the keratinous fibers or a further composition.  The catalyst useful in this type of reaction is preferably a titanium-based catalyst.  In particular, mention may be made of tetraalkoxytitanium catalysts of formula: ## STR2 ## in which R 2 is chosen from tertiary alkyl radicals such as tert-butyl, tert-amyl and 2,4-dimethyl-3-pentyl; R 3 represents an alkyl radical comprising 1 to 6 carbon atoms, preferably a methyl ethyl, n-propyl, isopropyl, n-butyl, sec-butyl or hexyl group and y is a number ranging from 3 to 4, more preferably 3,4 to 4.  The catalyst may be present in at least one of the compositions applied to the keratinous fibers or an additional composition in a content ranging from 0.0001% to 20% by weight relative to the total weight of the composition.  2c Diluent At least one of the compositions applied to the keratinous fibers or an additional composition may further comprise a volatile silicone oil (or diluent) intended to reduce the viscosity of the composition.  This oil may be selected from linear short chain silicones such as hexamethyldisiloxane, octamethyltrisiloxane, cyclic silicones such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane and mixtures thereof.  This silicone oil may represent from 5% to 95%, preferably from 10 to 80% by weight relative to the weight of the composition comprising it.  By way of example of a combination of compounds X and Y bearing alkoxysilane groups and reacting by condensation, there may be mentioned the combination of the following mixtures A 'and B' prepared by the company Dow Corning: 2910302 Mixture A ': Ingredient (INCI name) N CAS Content Function (% by weight) Bis-Trimethoxysiloxyethyl PMN87176 25-45 Polymer Tetramethyldisiloxyethyl Dimethicone Silica Silylate 68909-20-6 5-20 Charge Disiloxane 107-46-0 30-70 Solvent Mixture B ': Ingredient ( INCI name) N CAS Content Function (% by weight) Disiloxane 107-46-0 80-99 Tetra T solvent Butyl Titanate - 1-20 Catalyst It should be noted that the identical compounds X and Y are combined in the mixture AT'.  3 / Crosslinking in the presence of peroxide: This reaction is preferably carried out by heating at a temperature greater than or equal to 50 ° C., preferably greater than or equal to 80 ° C., up to 120 ° C.  The compounds X and Y, which are identical or different, comprise in this case at least two side groups ûCH3 and / or at least two side chains bearing a group -CH3.  The compounds X and Y are preferably silicone and may be chosen, for example, from high molecular weight non-volatile linear polydimethylsiloxanes having a degree of polymerization of greater than 6 having at least two silicon-bonded side groups connected to the silicon atom and or at least two side chains bearing a -CH3 group.  Mention may be made, for example, of the polymers described in the Reactive Silicones Catalog of Gelest Inc. , 2004 Edition, page 6, and especially copolymers (also called vinylmethylsiloxane-dimethylsiloxane copolymers) of molecular weights ranging from 500,000 to 900,000 and viscosity greater than 2,000,000 cSt.  Peroxides that can be used in the context of the invention include benzoyl peroxide, 2,4-dichlorobenzoyl peroxide and mixtures thereof.  The peroxid (s) may be present in at least one of the compositions applied to the keratin fibers or a further composition.  When at least one catalyst and / or at least one peroxide is applied to the keratin fibers, the compound (s) X, the compound (s) Y, the catalyst (s) and / or the peroxide (s) are not stored simultaneously in the same composition.  They can however be mixed at the time of application.  According to one embodiment, the hydrosilylation reaction or the condensation reaction or else the crosslinking reaction in the presence of a peroxide between compounds X and Y is accelerated by a heat input by raising, for example, the temperature of the system between 25 C and 180 C.  The system will react in particular on keratinous fibers.  In general, irrespective of the type of reaction by which compounds X and Y react together, the molar percentage of X with respect to all compounds X and Y, i.e. X / (X + Y) x 100 may range from 5% to 95%, preferably from 10% to 90%, more preferably from 20% to 80%.  Likewise, the molar percentage of Y relative to all of the compounds X and Y, i.e., the ratio Y / (X + Y) x 100, can vary from 5% to 95%, from preferably from 10% to 90%, more preferably from 20% to 80%.  Compound X may have a weight average molecular weight (Mw) of from 150 to 1,000,000, preferably from 200 to 800,000, more preferably from 200 to 250,000.  Compound Y may have a weight average molecular weight (Mw) of from 200 to 1,000,000, preferably from 300 to 800,000, more preferably from 500 to 250,000.  The compound X can represent from 0.5% to 95% by weight relative to the total weight of the composition comprising it, preferably from 1% to 90% and better still from 5% to 80%.  The compound Y may represent from 0.05% to 95% by weight relative to the total weight of the composition comprising it, preferably from 0.1% to 90% and better still from 0.2% to 80%.  The ratio between the compounds X and Y can be varied so as to modulate the reaction rate and therefore the film formation speed or also to adapt the properties of the formed film (for example its adhesive properties) according to the application sought.  In particular, the compounds X and Y may be present in a molar X / Y ratio ranging from 0.05 to 20 and better still from 0.1 to 10.  At least one of the compositions applied to the keratinous fibers or an additional composition may comprise fillers.  By way of example, these fillers may be colloidal calcium carbonate which may or may not be treated with stearic acid or stearate, silica such as pyrogenic silicas, precipitated silicas, silicas treated for hydrophobing, ground quartz, alumina, aluminum hydroxide, titanium dioxide, diatomaceous earth, iron oxide, carbon black, and graphite.  Synthetic silicas whose surface is modified with silicone compounds to render them hydrophobic at the surface are particularly preferred.  These fillers are differentiated from one another by their surface properties, the silicone compounds used to treat the silica, and the way in which the surface treatment is carried out.  Such fillers make it possible to reduce the viscosity of the formulation obtained from compounds X and / or Y.  In addition, resin-based reinforcing fillers can also be used.  Filler silica, calcium carbonate, resin fillers are preferred.  By way of example, mention may be made of the treated feedstocks Cab-O-Sil® TS-530, Aerosil® R8200 and Wacker HDX® H2000.  Oxidizing agents According to one particular embodiment of the invention, the oxidizing agent (s) is (are) chosen from: hydrogen peroxide or an agent capable of producing hydrogen peroxide by hydrolysis, such as peroxide or hydrogen peroxide; urea; Persalts such as persulfates, perborates, ammonium or alkali metal percarbonates; Alkaline bromates; • magnesium monoperoxyphthalate; Nitrites and more particularly alkali metal, acalinoterrous or ammonium nitrites, organic derivatives of nitrites.  The preferred nitrites are sodium nitrite or ammonium nitrite; Periodic acid and its water-soluble salts.  Preferred salts are lithium, sodium, potassium, rhubidium, cesium, magnesium, calcium, strontium, manganese, iron, copper, zinc, and aluminum salts.  More particularly preferred are the sodium and potassium salts; Alkali metal ferricyanides and in particular potassium ferricyanide; • silver oxide; • Fenton's reagent; • lead oxide (IV); Anions of a metal chosen from permanganates or dichromates.  More particularly preferred are potassium permanganate and sodium dichromate; • the metal salts of group III to VIII of the periodic table, such as salts of manganese, cobalt, iron, copper, silver, such as, for example, manganese sulphate, manganese lactate, cobalt chloride ferric chloride, cupric chloride, ammoniacal silver nitrate, copper salts which are preferred.  These metal salts may be in the free state or adsorbed; • rare earth salts.  These are selected from lanthanide salts, cerium salts Ce3 +, Ce4 +, lanthanum Lai + salts, europium Eue +, Eu3 +, gadolinium salts Gd3 +, Ytterbium salts Yb2 +, Yb3 +, dysprosium salts. Dy3 +.  The preferred salts are sulphates, chlorides or nitrates.  Preferably, Ce3 + or Ce4 + will be selected as sulfate or chloride; • sodium hypochlorite; • benzoquinone.  According to a preferred embodiment of the invention, the oxidizing agent (s) useful in the context of the present invention are chosen from hydrogen peroxide or an agent capable of producing hydrogen peroxide by hydrolysis such as urea peroxide.  According to another preferred embodiment of the invention, the oxidizing agent (s) is (are) chosen from persalts, and in particular persulfates.  The oxidizing agent (s) are generally present in an amount of between 0.0001 and 30%, preferably between 0.001 and 15% by weight, relative to the total weight of the compositions applied to the keratinous fibers.  Alkaline agents According to a particular embodiment of the invention, the process comprises the application to the keratinous fibers of at least one alkaline agent.  The alkaline agent (s) may be chosen from ammonia, ammonium salts such as ammonium chloride, ammonium sulphate, ammonium phosphate or ammonium nitrate, silicates, phosphates or alkali or alkaline-earth metal carbonates or bicarbonates, such as lithium, sodium, potassium, magnesium, calcium, barium, organic amines, and in particular alkanolamines such as monoethanolamine, and their mixtures.  Preferably, the alkaline agent (s) are chosen from ammonium chloride, silicates, carbonates, and mixtures thereof.  The concentration of alkaline agents is generally between 0.001 and 30% by weight, and preferably between 0.01 and 20% by weight of the total weight of the compositions applied to the keratinous fibers.  Organic solvents An organic solvent is understood to mean an organic substance which is liquid at 25 ° C. and the atmospheric pressure (760 mmHg) capable of dissolving another substance without chemically modifying it.  The organic solvent (s) useful in the context of the invention are distinct from the compounds X and Y that are useful in the context of the invention.  The organic solvent or solvents are, for example, chosen from aromatic alcohols such as benzyl alcohol, phenoxyethanol and phenylethyl alcohol; liquid fatty alcohols, especially of C10-C30; C1-C6 alkanols such as ethanol, isopropanol, n-propanol, butanol, n-pentanol, 1,2-propanediol, 1,3-propanediol, 1-methoxy-2-propanol 1-ethoxy-2-propanediol, 1,3 and 1,4-butanediol, 1,2-hexanediol; polyols and polyol ethers having a free -OH function such as 2-butoxyethanol, propylene glycol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether and monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono butyl ether, neopentyl glycol, isoprene glycol, glycerol, glycol, dipropylene glycol, butylene glycol, butyl diglycol; volatile silicones such as linear short chain silicones such as hexamethyldisiloxane and octamethyltrisiloxane, cyclic silicones such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, polydimethylsiloxanes modified or not by alkyl and / or amine functional groups; and / or imine and / or fluoroalkyl and / or carboxylic acid and / or betaine and / or quaternary ammonium; liquid modified polydimethylsiloxanes; mineral, organic or vegetable oils; alkanes and more particularly linear or branched alkanes, from C5 to C20; liquid fatty acids; liquid fatty esters and more particularly liquid benzoates or salicylates of liquid fatty alcohol.  The organic solvent or solvents are preferably chosen from organic oils; silicones such as volatile silicones, silicone gums or silicone oils or not and mixtures thereof; mineral oils; vegetable oils such as olive oil, castor oil, rapeseed oil, copra oil, wheat germ oil, sweet almond oil, avocado oil, macadamia oil, apricot oil, safflower oil, bancoulier nut oil, camellina, tamanu, lemon or organic compounds such as linear or branched C 5 -C 20 alkanes such as isododecane, isohexadecane, isoparaffinic compounds of the type sold under the name Isopar E, acetone, methyl ethyl ketone, C1-C20 acid esters of liquid and C1-C8 alcohols such as methyl acetate, butyl acetate, ethyl acetate and isopropyl myristate dimethoxyethane, diethoxyethane, C10-C30 liquid fatty alcohols such as oleic alcohol, esters of fatty alcohols or of liquid fatty acids such as C10-C30 fatty alcohol benzoates and mixtures thereof; isononyl isononanoate, isostearyl malate, pentaerythrityl tetraisostearate, tridecyl trimate; polybutene oil; the cyclopentasiloxane mixture (14.7% by weight) / dihydroxylated polydimethylsiloxane at positions a and w (85.3% by weight), or mixtures thereof.  According to a preferred embodiment, the one or more organic solvents are chosen from silicones such as liquid polydimethylsiloxanes and liquid modified polydimethylsiloxanes, their viscosity at 25 C being between 0.1 and 1,000,000 cst, and more preferably between 1 and 30,000 cst.  The following oils are preferably mentioned: - the mixture of alpha-omega-dihydroxylated polydimethylsiloxane / cyclopentadimethylsiloxane (14.7 / 85.3) sold by Dow Corning under the name DC 1501 Fluid; the mixture of alpha-omega-dihydroxylated polydimethylsiloxane / polydimethylsiloxane marketed by Dow Corning under the name DC 1503 Fluid; the dimethicone / cyclopentadimethylsiloxane mixture marketed by Dow Corning under the name DC 1411 Fluid or that marketed by Bayer under the name SF1214; cyclopentadimethylsiloxane sold by Dow Corning under the name DC245 Fluid; and the respective mixtures of these oils.  These organic solvents can serve as a diluent for polycondensation reactions.  The organic solvent or solvents generally represent from 0.01 to 99%, preferably from 50 to 99% by weight relative to the total weight of the composition comprising them.  According to a particular embodiment of the invention, the method comprises a first step of bleaching the keratinous fibers using at least one oxidizing agent and a second step of cosmetic treatment of the keratinous fibers with the aid of at least two compounds X and Y, able to react together, at least one of these compounds being silicone, in the presence optionally of at least one organic solvent.  The order of execution of the first and second steps is irrelevant.  The first and second steps can be performed the same day or a few days apart.  The step of bleaching keratinous fibers consists in applying to the keratin fibers a composition comprising at least one oxidizing agent.  According to a particular embodiment, the bleaching step consists in applying to the keratinous fibers an aqueous composition (A) comprising at least one peroxygenated salt as defined above, at least one alkaline agent as defined above. and hydrogen peroxide.  This composition may be obtained from the mixture between an anhydrous composition (B) comprising at least one peroxygenated salt as defined above, an aqueous composition (C) comprising at least one alkaline agent as defined above and a composition ( D) aqueous hydrogen peroxide.  This composition may also be obtained from the mixture between an anhydrous composition (E) comprising at least one peroxygenated salt and at least one alkaline agent as defined above and an aqueous hydrogen peroxide composition (D).  The aqueous compositions (C) and (D) comprise water and optionally at least one organic solvent for solubilizing compounds that are not sufficiently soluble in water.  Examples of organic solvents are lower C1-C4 alkanols, such as ethanol and isopropanol; glycerol; glycols and glycol ethers such as 2-butoxyethanol, propylene glycol, propylene glycol monomethyl ether, and aromatic alcohols such as benzyl alcohol or phenoxyethanol, the like and mixtures thereof.  The solvents may be present in proportions preferably of between 1 and 40% by weight relative to the total weight of the composition, and more preferably between 5 and 30% by weight approximately.  The composition (D) preferably has a pH of less than 7, the acidic pH guaranteeing the stability of the hydrogen peroxide in this composition.  The compositions (C) and (D) may be in various forms, such as in the form of liquids, creams, gels, or in any other form suitable for dyeing keratinous fibers.  The anhydrous compositions (B) and (E) may be in the form of a powder or a paste.  They may comprise an organic inert liquid phase.  By liquid phase is meant in the sense of the present invention any phase 5 capable of flow at room temperature, generally between 15 C and 40 C, and at atmospheric pressure, under the action of its own weight.  By way of example of an inert liquid phase, mention may be made of polydecenes of formula C1or, H [(2on> +2) in which n varies from 3 to 9 and preferably from 3 to 7, esters of fatty alcohols or fatty acids, esters or diesters of C12-C24 fatty acid sugars, cyclic ethers or cyclic esters, silicone oils, mineral oils or vegetable oils, or mixtures thereof.  The compounds of formula C1or, H [(2on> +2) with n varying from 3 to 9 correspond to the name "polydecene" of the CTFA Dictionary 7th edition 1997 of the Cosmetic, Toiletry and Fragrance Association, USA, as well as to the same 15 appellation I. NOT. vs. I.  in the USA and Europe.  They are hydrogenation products of poly-1-decenes.  Among these compounds, it is preferred according to the invention those for which in the formula, n varies from 3 to 7.  By way of example, mention may be made of the product sold under the name Silkflo 366 NF Polydecene by the company Amoco Chemical, those sold under the name Nexbase 2002 FG, 2004 FG, 2006 FG and 2008 FG by the company Fortum.  Examples of esters of fatty alcohols or of fatty acids are: esters of linear or branched C 3 -C 6 saturated lower monohydric alcohols with monofunctional C12-C24 fatty acids; these may be linear or branched, saturated or unsaturated and chosen in particular from oleates, laurates, palmitates, myristates, behenates, cocoates, stearates, linoleates, linolenates, caprates, arachidonates, or mixtures thereof, such as, in particular, oleo-palmitates, oleo-stearates, palmito-stearates.  Among these esters, it is more particularly preferred to use isopropyl palmitate, isopropyl myristate and octyl dodecyl stearate.  esters of C3-C8 linear or branched monohydric alcohols with bifunctional C8-C24 fatty acids, the latter possibly being linear or branched, saturated or unsaturated, such as, for example, the isopropyl di-ester of sebacic acid; also called di-isopropyl sebacates; esters of linear or branched C 3 -C 8 monohydric alcohols with bifunctional C 2 -C 8 fatty acids, the latter being linear or branched, saturated or unsaturated, such as, for example, dioctyl adipate and dicaprylyl maleate; the ester of a trifunctional acid such as triethyl citrate.  With regard to the esters and diesters of C12-C24 fatty acid sugars, the term "sugar" means compounds which have several alcohol functions, with or without an aldehyde or ketone function, and which comprise at least 4 carbon atoms.  These sugars can be monosaccharides, oligosaccharides or polysaccharides.  As sugars which can be used according to the invention, mention may be made, for example, of sucrose (or sucrose), glucose, galactose, ribose, fuctose, maltose, fructose, mannose, arabinose, xylose, lactose, and their especially alkylated derivatives, such as methylated derivatives such as methylglucose.  The esters of sugars and of fatty acids that may be used according to the invention may be chosen especially from the group comprising the esters or mixtures of sugar esters described above and of linear or branched C12-C24 fatty acids. saturated or unsaturated.  The esters may be chosen from mono-, di-, tri- and tetraesters, polyesters and mixtures thereof.  These esters may be, for example, chosen from oleates, laurates, palmitates, myristates, behenates, cocoates, stearates, linoleates, linolenates, caprates, arachidonates, or mixtures thereof, such as, in particular, oleo-palmitate, oleostearate and palmitate mixed esters. stearates.  More particularly, it is preferred to use the mono- and diesters and especially the mono- or dioleates, stearates, behenates, oleopalmitates, linoleates, linolenates, oleostearates, sucrose, glucose or methylglucose.  By way of example, mention may be made of the product sold under the name Glucate DO by the company Amerchol, which is a methylglucose dioleate.  Examples of esters or mixtures of fatty acid sugar esters are: the products sold under the names F160, F140, F110, F90, F70 and SL40 by the company Crodesta; designating sucrose palmito stearates of 73% monoester and 27% di- and tri-ester, 61% monoester and 39% di-, tri- and tetraester, 52% of monoester and 48% di-, tri- and tetraester, 45% monoester and 55% di-, tri- and tetraester, 39% monoester and 61% di-, tri- and tetraester, and sucrose mono-laurate; The products sold under the name Ryoto Sugar Esters, for example referenced B370 and corresponding to sucrose behenate formed from 20% monoester and 80% di-triester-polyester; the sucrose mono-di-palmito-stearate marketed by Goldschmidt under the name Tegosoft PSE.  Examples of cyclic ethers and cyclic esters are γ-butyrolactone, dimethyl isosorbide or diisopropyl isosorbide.  Silicone oils can also be used as an inert organic liquid phase.  More particularly, the suitable silicone oils are liquid and non-volatile silicone fluids with a viscosity of less than or equal to 10,000 mPa. at 25 ° C., the viscosity of the silicones being measured according to ASTM Standard 445 Appendix C.  Silicone oils are further defined in Walter NOLL's "Chemistry and Technology of Silicones" (1968) - Academic Press.  Among the silicone oils that may be used according to the invention, mention may be made in particular of the silicone oils sold under the names DC-200 fluid-5 mPa. s, DC-200 fluid - 20 mPa. s, DC-200 fluid - 350 mPa. s, DC-200 fluid - 1000 mPa. s, DC-200 fluid - 10,000 mPa. s by Dow Corning.  The mineral oils can also be used as organic inert liquid phase, for example paraffin oil.  Vegetable oils may also be suitable, including avocado oil, olive oil or liquid jojoba wax.  Preferably, the organic inert liquid phase is chosen from the group formed by the polydecenes of formula C1ofH [(2on) +2] in which n varies from 3 to 9 and preferably from 3 to 7, the alcohols esters. fatty acids or fatty acids, and mixtures thereof.  The organic inert liquid phase content may vary between 5 and 60%, preferably between 10 and 50% by weight, and even more preferably between 15 and 45% by weight of the total weight of the composition.  The cosmetic treatment step of the keratinous fibers consists in applying to the keratinous fibers at least two compounds X and Y, able to react together, at least one of these compounds being silicone as defined above, and possibly at least minus an organic solvent.  Before being applied to the keratinous fibers, the compound (s) X and the compound (s) Y may be present in the same composition, the optional organic solvent (s) being present in this composition, or two distinct compositions called first and second compositions, the optional organic solvent or solvents being present in the first composition and / or in the second composition.  According to a particular embodiment, the process for the cosmetic treatment of keratinous fibers consists in applying to the keratinous fibers at least one layer of a mixture of a first composition comprising a compound X and a second composition comprising a compound Y ; at least one of the compounds X and Y being a silicone compound, said compounds X and Y being capable of reacting together by a reaction of hydrosilylation, condensation, or crosslinking in the presence of a peroxide, when they are brought into contact with each other, said mixture being obtained either extemporaneously before application to the keratin fibers, or simultaneously with its application to the keratinous fibers.  According to a first variant, the process for the cosmetic treatment of keratinous fibers consists in: a) extemporaneously mixing at least one first composition comprising a compound X and at least one second composition comprising a compound Y, at least one of the compounds X and Y being a silicone compound, and said compounds X and Y being capable of reacting together by a reaction of hydrosilylation, condensation, or crosslinking in the presence of a peroxide, when they are brought into contact with one another; with the other, then b) to apply at least one layer of the mixture to the keratinous fibers.  According to a second variant, the process for the cosmetic treatment of keratinous fibers comprises the application to the keratinous fibers of: a) at least one layer of a first composition comprising a compound X; b) at least one layer of a second composition comprising a compound Y; at least one of the compounds X and Y being a silicone compound, said compounds X and Y being capable of reacting together by a hydrosilation, condensation or crosslinking reaction in the presence of a peroxide, when they are put in contact with each other.  According to this second variant, it is possible to apply at least one layer of the first composition comprising the compound X to the keratinous fibers and then to deposit on the layer or layers of the first composition at least one layer of the second composition comprising the compound Y.  It is also possible to apply at least one layer of the second composition comprising the compound Y to the keratinous fibers and then to deposit on the layer or layers of the second composition at least one layer of the first composition comprising the compound X.  Alternatively, several layers of each of the first and second compositions can be alternately applied to the keratinous fibers.  According to another particular embodiment of the invention, the step of bleaching the keratinous fibers using at least one oxidizing agent and the step of treating the keratinous fibers using at least two compounds X and Y, able to react together, at least one of these compounds being silicone and optionally at least one organic solvent are simultaneously.  The method according to the invention then consists in applying to the keratin fibers a composition comprising: at least one compound X and at least one compound Y, at least one of the compounds X and Y being a silicone compound, said compounds X and Y being capable of reacting together by a hydrosilylation reaction, condensation, or crosslinking in the presence of peroxide, when they are brought into contact; At least one oxidizing agent; and - optionally at least one organic solvent and / or at least one alkaline agent.  According to a particular embodiment, the process according to the invention consists in applying to the keratin fibers an aqueous composition comprising: at least one compound X and at least one compound Y, at least one of the compounds X and Y being a silicone compound, said compounds X and Y being capable of reacting together by a hydrosilylation, condensation, or crosslinking reaction in the presence of peroxide, when they are brought into contact; at least one peroxygenated salt as defined above; at least one alkaline agent as defined above; - hydrogen peroxide; and optionally at least one organic solvent.  The composition applied to the keratin fibers may be derived from a composition (A) as defined above or from its mixture with one or more other compositions.  In this case, the compound (s) X and the compound (s) Y may be present within one and the same composition, the optional organic solvent (s) then being present in this composition, or the compound (s) X and the or the compounds Y may be present in two distinct compositions, the optional organic solvent or solvents being present in the composition comprising the compound (s) X and / or in the composition comprising the compound (s) Y.  Each of the compositions comprising the compound (s) X and / or the compound (s) Y may be the composition (A) or an additional composition.  The composition applied to the keratin fibers may also be derived from the mixture between a composition (B), a composition (C) and a composition (D) as defined above, optionally with one or more other compositions.  In this case, the compound (s) X and the compound (s) Y may be present within the same composition, the optional organic solvent or solvents then being present in this composition, or the compound (s) X and the the compounds Y may be present in two distinct compositions, the optional organic solvent (s) then being present in the composition comprising the compound (s) X and / or in the composition comprising the compound (s) Y.  Each of the compositions comprising the compound (s) X and / or the compound (s) Y may be one of the compositions (B), (C) or (D) or an additional composition.  The composition applied to the keratinous fibers may also be derived from the mixture between a composition (E) and a composition (D) as defined above, optionally with one or more other compositions.  In this case, the compound (s) X and the compound (s) Y may be present within the same composition, the optional organic solvent or solvents then being present in this composition, or the compound (s) X and the or the compounds Y may be present in two distinct compositions, the optional organic solvent (s) then being present in the composition comprising the compound (s) X and / or in the composition comprising the compound (s) Y.  Each of the compositions comprising the compound (s) X and / or the compound (s) Y may be one of the compositions (E) or (D) or an additional composition.  The composition (s) comprising the compound (s) X and / or the compound (s) Y may contain water in a proportion ranging from 1 to 99%, and preferably from 1 to 50% relative to the total weight of the compound. composition.  These compositions may be anhydrous, that is to say containing less than 1% by weight of water relative to the total weight of the composition.  These compositions may also be in the form of an emulsion and / or be encapsulated.  When these compositions are emulsions, they consist for example of a dispersed or continuous phase which may be water, C 1 -C 4 aliphatic alcohols or mixtures thereof and an organic phase insoluble in water.  Each composition useful in the process of the invention may also contain at least one agent usually used in cosmetics chosen, for example, from reducing agents, fatty substances, plasticizers, softeners, anti-foaming agents, agents and the like. moisturizers, pigments, clays, mineral fillers, UV filters, mineral colloids, peptizers, perfumes, preservatives, anionic, cationic, nonionic or amphoteric surfactants, fixing or non-binding polymers, proteins, vitamins, direct dyes, oxidation dyes, pearlescent agents, propellants, and inorganic or organic thickeners such as benzylidene sorbitol and N-acylamino acids, oxyethylenated waxes or not, paraffins , C10-C30 solid fatty acids such as stearic acid, lauric acid, C10-C30 fatty amides such as lauric diethanolamide, fatty alcohol esters or of solid fatty acids and mixtures thereof.  Compositions comprising hydrogen peroxide may also include oxygen release control agents such as carbonate or magnesium oxide.  The agents usually used in cosmetics and oxygen release control agents as defined above may be present in an amount for each of them ranging from 0.01 to 40%, preferably from 0.1 to 30% by weight. relative to the total weight of the composition containing them.  Of course, those skilled in the art will take care to choose this or these optional additional compounds in such a way that the advantageous properties intrinsically attached to the composition according to the invention are not, or not substantially, impaired by the one or more proposed additions.  Each composition useful in the process according to the invention comprises a cosmetically acceptable medium, carrying the compound (s) X and / or the compound (s) Y, and chosen in such a way that compounds X and Y are capable of reacting with each other by reaction of hydrosilylation, condensation, or crosslinking in the presence of peroxide, after the application of the cosmetic composition to the hair.  The present invention also relates to the use for the bleaching of keratin fibers of: at least one compound X and at least one compound Y, at least one of compounds X and Y being a silicone compound, said compounds X and Y being capable of reacting together by a hydrosilylation, condensation, or crosslinking reaction in the presence of peroxide, when contacted; at least one oxidizing agent; and 2910302 39 - optionally at least one organic solvent and / or at least one alkaline agent; the compound (s) X, the compound (s) Y, the oxidizing agent (s), the optional organic solvent (s) and any alkaline agent (s) being as defined above.  The present invention also relates to a kit for the bleaching of keratinous fibers comprising at least two compositions packaged separately, the kit comprising: at least one compound X and at least one compound Y, at least one of the compounds X and Y being a silicone compound, said compounds X and Y being capable of reacting together by a hydrosilylation reaction, condensation, or crosslinking in the presence of peroxide, when they are brought into contact; at least one oxidizing agent; and optionally at least one organic solvent and / or at least one alkaline agent; the compound (s) X, the compound (s) Y, the oxidizing agent (s), the optional organic solvent (s) and any alkaline agent (s) being as defined above.  The present invention also relates to a composition for the bleaching of keratinous fibers comprising: at least one compound X and at least one compound Y, at least one of compounds X and Y being a silicone compound, said compounds X and Y being capable of reacting together by a hydrosilylation, condensation, or crosslinking reaction in the presence of peroxide, when contacted; at least two oxidizing agents different from each other; and optionally at least one organic solvent and / or at least one alkaline agent; The compound (s) X, the compound (s) Y, the oxidizing agents, the optional organic solvent (s) and any alkaline agent (s) being as defined above.  According to a particular embodiment, one of the oxidizing agents present in the composition according to the invention is chosen from persulfates, peroxides, ammonium or alkali metal percarbonates and the other is peroxide of hydrogen.  The invention will be more fully illustrated with the aid of the following nonlimiting examples.  EXAMPLES In the composition examples described below, use is made of the following mixtures A 'and B' prepared by the company Dow Corning: Mixture A ': Ingredient (INCI name) N CAS Content Function (% by weight) Bis-Trimethoxysiloxyethyl PMN87176 25-45 Polymer Tetramethyldisiloxyethyl Dimethicone Silica Silylate 68909-20-6 5-20 Charge Disiloxane 107-46-0 30-70 Solvent Mixture B ': Ingredient (INCI Name) N CAS Content Function (% by weight) Disiloxane Example 1 Compositions 1 and 2 as defined below are prepared: Composition 1 in g Potassium persulfate 4.5 Hydrogen peroxide 20 volumes 50

  Ammonia (20.5% NH 3) 3 Cyclopentadimethylsiloxane sold by Dow Corning as DC245 Fluid Blend A 2910302 42 Cyclopentadimethylsiloxane Composition 2 sold by Dow Corning under the name DC245 Fluid Blend B '0 Composition 3 is carried out at the time of use. Compositions 1 and 2 are extemporaneously blended. The mixture obtained is applied to a lock of 2.5 g of natural gray hair with 90% of clean and moist white hair. After 30 minutes break, the wick is rinsed, washed with a standard shampoo, and then dried with a hair dryer. The wick is discolored and has a smooth and soft touch. EXAMPLE 2 The compositions 3 and 4 as defined below are prepared: Cyclopentadimethylsiloxane composition 3 marketed by Dow 87.78 Corning under the name DC245 Fluid Mixture A '11.11 Composition 4 in g Mixture B' 1, Compositions 3 and 4 are extemporaneously mixed. 0.25 g of the mixture thus obtained is applied, preferably with a brush, to a moist lock of natural hair of pitch 1 of 1 g. After one hour of exposure, the wick is dried with the helmet for 30 minutes then combed. A terminal shampoo is optionally performed. A hair bleaching composition comprising 4.5% by weight of potassium persulfate, 50% by weight hydrogen peroxide (6% by weight H 2 O 2), 3% by weight ammonia is prepared in the cosmetic medium. (at 20.5% by NH 3).

On the wick obtained previously, marked M, the fading composition is applied. The fading composition is also applied to a lock of natural hair of pitch pitch labeled T.

It is observed that the wick M which has undergone treatment with the blends A 'and B' has a more uniform color along its length than the control wick T simply discolored. It is said that the wick M has a better homogeneity than the control wick T.

EXAMPLE 3 Compositions 5 and 6 as defined below are prepared: Cyclopentadimethylsiloxane composition sold by Dow 87.78 Corning as DC245 Fluid Blend A '11.11 Composition 6 in g Blend B' 1, A hair bleach composition comprising 4.5% by weight of potassium persulfate, 50% by weight hydrogen peroxide (6% by weight H 2 O 2), 3% by weight, is prepared in the cosmetic medium. ammonia (at 20.5% by NH 3). 5 g of this composition are applied to two strands of 1 g of natural hair of 4 pitch of 4 clean and wet. After 30 minutes of installation, the locks are rinsed and then wrung out. Compositions 5 and 6 are extemporaneously mixed. 0.5 g of the mixture obtained is applied to one of the colored locks. After one hour of exposure, the wick is dried in a hair dryer for 2 minutes.

Two faded wicks are obtained but the wick which has subsequently been treated with the blends A 'and B' has a more pleasant feel.

In the composition examples described below, the following combination of mixtures A and B prepared by the company Dow Corning is used: MIXTURE A: Ingredient (INCI name) N CAS Content Function (% by weight) Dimethyl Siloxane, 68083-55-95 Polymer Dimethylvinylsiloxy-terminated 19-2 Silica Silylate 68909- 10-40 Charge 20-6 1,3-Diethenyl-1,1,3,3- 68478- Trace Catalyst Tetramethyldisiloxane Complexes 92-2 Tetramethyldivinyldisiloxane 2627-95 - 0.1-1 Polymer 4 MIXING B: Ingredient (INCI name) N CAS Content Function (% by weight) Dimethyl Siloxane, 68083-19- 55-95 Polymer Dimethylvinylsiloxy-2 terminated Silica Silylate 68909-20- 10-40 Charge 6 Dimethyl Example 4 Compositions 7 and 8 as defined below are prepared: 2910302 Composition 7 in g Potassium persulfate 4.5 Hydrogen peroxide 20 volumes 50 Ammonia, Methylhydrogen 68037-59- 1-10 Polymer Siloxane, trimethylsiloxy-terminated (at 20.5% NH 3) 3 Cyclopentadimethylsi loxane marketed by Dow Corning under the name DC245 Fluid Mixture A 3 Composition 8% by weight Cyclopentadimethylsiloxane marketed by Dow Corning 10 g under the name DC245 Fluid Mixture B 3 g Composition 7 is produced at the time of use. The compositions 7 and 8 are extemporaneously blended. The resulting blend is applied to a wick of 2.5 g of natural gray hair with 90% clean, moist white hair. After 30 minutes break, the wick is rinsed, washed with a standard shampoo, and then dried with a hair dryer. The wick is discolored and has a smooth and soft touch.

EXAMPLE 5 Compositions 9 and 10 as defined below are prepared: Cyclopentadimethylsiloxane Composition 9 sold by Dow 92 Corning under the name DC245 Fluid Mixture A 8 Composition 10% by weight Cyclopentadimethylsiloxane sold by Dow Corning 92 g under the name DC245 Fluid Blend B 8 g 2910302 46 The compositions 9 and 10 are extemporaneously blended. 0.25 g of the mixture thus obtained is applied, preferably with a brush, on a wet wick of natural hair of pitch 4 of 1 g. After one hour of exposure, the wick is dried in the helmet for 30 minutes and then combed. A terminal shampoo is optionally performed. A composition is prepared for bleaching the hair comprising in the cosmetic medium 4.5% by weight of potassium persulfate, 50% by weight of hydrogen peroxide (at 6% by weight in H 2 O 2), 3% by weight of ammonia (at 20.5% by NH 3).

On the wick obtained previously, marked M, the fading composition is applied. The bleaching composition is also applied to a lock of natural hair of T.sub.1 T.sub.1 T.sub.4. It is observed that the wick M which has undergone treatment with blends A and B has a more uniform color along its length than the wick. witness T simply discolored. The wick M is said to be better unison than the control wick. EXAMPLE 6 The compositions 11 and 12 as defined below are prepared: Cyclopentadimethylsiloxane composition 11 marketed by Dow 92 Corning under the name DC245 Fluid Blend 8 Composition 12% by weight Cyclopentadimethylsiloxane marketed by Dow Corning 92 g under the name DC245 Fluid Mixture B 8 g A composition for bleaching hair comprising, in the cosmetic medium, 4.5% by weight of potassium persulfate, 50% by weight of oxygenated water (6% by weight of H 2 O 2), 3% by weight of ammonia (at 20.5% by NH 3). 5 g of this composition are applied to two locks of 1 g of natural hair of 4 tone clean and wet. After 30 minutes of installation, the 5 locks are rinsed and then wrung out. The compositions 11 and 12 are mixed extemporaneously. 0.5 g of the mixture thus obtained is applied to one of the colored locks. After one hour of exposure, the wick is dried in a hair dryer for 2 minutes. Two faded locks are obtained, but the wick which has subsequently been treated with blends A and B has a more pleasant feel.

Claims (15)

  1. A process for bleaching keratinous fibers comprising the application to the keratinous fibers of: at least one compound X and at least one compound Y, at least one of compounds X and Y being a silicone compound, said compounds X and Y being capable of reacting together by a hydrosilylation reaction, condensation, or crosslinking in the presence of peroxide, when they are brought into contact; at least one oxidizing agent; and - optionally at least one organic solvent.   2. Process according to claim 1, in which the compound (s) X, the compound (s) Y, the oxidizing agent (s) and any organic solvent (s) may be present in several distinct compositions containing the compound (s) X, the or the compounds Y, the oxidizing agent (s) and the organic solvent (s), alone or as a mixture, or in a single composition containing the compound (s) X, the compound (s) Y, the oxidizing agent (s) and the or possible organic solvents.   3. Method according to claim 1 or 2 comprising the application of at least one catalyst.   4. Method according to any one of the preceding claims wherein compounds X and Y are capable of reacting by hydrosilylation.   5. Method according to claim 4 wherein the compound X is selected from silicone compounds comprising at least two unsaturated aliphatic groups.   6. The method of claim 5 wherein the compound X is a polyorganosiloxane comprising a silicone main chain whose unsaturated aliphatic groups are pendant to the main chain (side group) or located at the ends of the main chain of the compound (end group).   7. Method according to any one of claims 4 to 6 wherein the compound X is selected from polyorganosiloxanes comprising at least two unsaturated aliphatic groups each bonded to a silicon atom. 2910302 49   8. Process according to one of Claims 4 to 7, in which the compound X is chosen from polyorganosiloxanes comprising siloxane units of formula: ## STR3 ## in which: R represents a linear or cyclic monovalent hydrocarbon group comprising from 1 to 30; carbon atoms; m is equal to 1 or 2, and R 'represents an unsaturated aliphatic hydrocarbon group comprising from 10 to 10 carbon atoms or an unsaturated cyclic hydrocarbon group comprising from 5 to 8 carbon atoms.   9. The process according to claim 8 wherein the polyorganosiloxane of formula (I) is such that R 'is a vinyl group or a group R "-CH = CHR" "wherein R" is a divalent aliphatic hydrocarbon chain, comprising 1 to 8 carbon atoms, bonded to the silicon atom and R "'is a hydrogen atom or an alkyl radical comprising from 1 to 4 carbon atoms.   10. The method of claim 8 or 9 wherein R represents an alkyl radical comprising 1 to 10 carbon atoms or a phenyl group and R 'is selected from vinyl groups. 20   11. The method of claim 10 wherein the polyorganosiloxanes further comprise units of the formula: ## STR5 ## wherein R is a group as defined in claim 8, and n is equal to 1, 2 or 3. 25   12. The method of claim 4 wherein the compound X is selected from oligomers or organic polymers, oligomers or hybrid organic / silicone polymers, said oligomers or polymers bearing at least 2 reactive unsaturated aliphatic groups and mixtures thereof. (I) 2910302 50   13. Method according to one of claims 4 to 12 wherein the compound Y is selected from organosiloxanes comprising at least two free Si-H groups.   14. Process according to one of Claims 4 to 13, in which the compound Y is chosen from organosiloxanes comprising at least one alkylhydrogenosiloxane unit of the following formula: in which: R represents a linear or cyclic monovalent hydrocarbon group, comprising: from 1 to 30 carbon atoms or a phenyl group; and - p is 1 or 2. 17. The process according to claim 14 wherein the compound Y is such that the R radicals represent a C1-C10 alkyl group. 18. A process according to any one of claims 13 to 15 wherein the Y organosiloxanes comprise at least two alkylhydrogensiloxane units of the formula (H3C) (H) SiO and optionally include (H3C) 2SiO units. 19. Method according to one of claims 4 to 16 wherein the catalyst is a platinum or tin catalyst. 20. Process according to claim 17 wherein the catalyst or catalysts represent from 0.0001% to 20% by weight relative to the total weight of the composition comprising it. 21. Process according to any one of claims 4 to 13 wherein the compound X is a polydimethylsiloxane end vinyl groups and the compound Y is methylhydrogensiloxane. 20. The process of any one of claims 1 to 3 wherein compounds X and Y are capable of condensation reaction. 21. The process as claimed in claim 20, in which the compounds X and Y, which are identical or different, are silicone compounds whose main chain comprises at least two alkoxysilane groups and / or at least two silanol (Si-OH) groups, and / or at the end of the chain. 22. The process according to claim 20 or 21, in which the compounds X and / or Y, which are identical or different, mainly comprise units of the formula: (IV) in which the Rs independently represent a radical chosen from the groups alkyl having 1 to 6 carbon atoms, phenyl, fluorinated alkyl groups, and s is 0, 1, 2 or 3. 23. The process of claim 22 wherein the compounds X and / or Y, which are identical or Different compounds include units of the formula: wherein R 9 is as defined in claim 22, and f is such that the polymer has a viscosity at 25 C ranging from 0.5 to 3000 Pa.s. 24. The process according to one of claims 20 to 23 wherein the polyorganosiloxanes comprise at least 2 terminal trialkoxysilane groups per polymer molecule, said groups having the following formula: SR (OR) -x, in which: R radicals represent independently methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl; R 'is methyl or ethyl; x is 0 or 1; and Z is selected from: divalent hydrocarbon groups having no ethylenic unsaturation and comprising from 2 to 18 carbon atoms, combinations of divalent hydrocarbon radicals and siloxane segments of the formula: R 9 R 1 ', 9 R 9 R 9 being as defined in claim 22, G is a divalent hydrocarbon radical having no ethylenic unsaturation and comprising from 2 to 18 carbon atoms and c is an integer from 1 to 6. 25. Process according to any one of the following: Claims 20 to 24 wherein the polyorganosiloxanes are selected from polymers of the formula: wherein R, R ', R9, Z, x, and are as defined in any one of claims 22 to 24. 26. The method of claim 20 wherein the compound X is selected from organic oligomers or polymers or hybrid organic / silicone oligomers or polymers, said polymers or oligomers compr at least two alkoxysilane groups and the compound Y is selected from polyorganosiloxanes. 27. Method according to one of claims 20 to 26 wherein the catalyst is a titanium-based catalyst. 28. The method of claim 27 wherein the catalyst or catalysts are present in a content ranging from 0.0001% to 20% by weight relative to the total weight of the composition comprising them. 29. The process as claimed in claim 20, in which the compounds X and Y represent a mixture of polydimethylsiloxanes containing methoxysilane groups. 30. Process according to any one of claims 1 to 3 wherein the compounds X and Y are capable of reacting by crosslinking in the presence of peroxide. 31. The process as claimed in any one of the preceding claims, wherein at least one filler selected from silica or surface-treated silica is applied to the keratinous fibers. 32. The process as claimed in one of the preceding claims, in which the compound X has a weight-average molecular mass (Mw) ranging from 150 to 1,000,000. 33. A process according to any one of the preceding claims in which the compound Y has a weight average molecular weight (Mw) of from 200 to 1,000,000. 34. A process according to any one of the preceding claims wherein the oxidizing agent (s) is (are) selected from: • hydrogen peroxide or an agent capable of produce hydrogen peroxide by hydrolysis; • persalts; • alkaline bromates; Magnesium monoperoxyphthalate; • nitrites; • periodic acid and its water-soluble salts; • ferricyanides of alkali metals; • silver oxide; • Fenton's reagent; • lead oxide (IV); Anions of a metal chosen from permanganates or dichromates; • the metal salts of group III to VIII of the periodic table; Rare earth salts chosen from lanthanide salts, cerium Ce3 +, Ce4 + salts, lanthanum Lai +, europium Eue +, Eu3 + salts, gadolinium Gd3 + salts, Ytterbium salts Yb2 +, Yb3 +, dysprosium Dy3 +; • sodium hypochlorite; • benzoquinone. 48. The process according to claim 34 wherein the oxidizing agent (s) is (are) selected from hydrogen peroxide and agents capable of producing hydrogen peroxide by hydrolysis. 49. The method of claim 35 wherein the agent capable of producing hydrogen peroxide by hydrolysis is urea peroxide. 50. The method of claim 34 wherein the oxidizing agent (s) is (are) selected from persalt. 51. The method of claim 37 wherein the oxidizing agent (s) is (are) chosen from persulfates. 52. Process according to any one of the preceding claims, in which the oxidizing agent (s) are present in an amount of between approximately 54% and 30% by weight of the total weight of the compositions applied to the keratinous fibers. 40. Process according to any one of the preceding claims, in which at least one alkaline agent is applied to the keratinous fibers. 41. Process according to claim 40, in which the alkaline agent (s) is (are) chosen from ammonia, ammonium salts, silicates, phosphates or carbonates or bicarbonates of alkali or alkaline-earth metals, organic amines. and their mixtures. 42. The process according to claim 41 wherein the alkaline agent (s) are selected from ammonium chloride, silicates, carbonates, and mixtures thereof. 43. Process according to any one of claims 40 to 42 wherein the concentration of alkaline agents is between 0.001 and 30% by weight of the total weight of the compositions applied to the keratinous fibers. 44. A process according to any one of the preceding claims wherein the one or more organic solvents are selected from organic oils; silicones; mineral oils; vegetable oils; C5-C20 alkanes; acetone; methyl ethyl ketone; esters of C1-C20 acids and C1-C8 alcohols; dimethoxyethane; diethoxyethane; C10-C30 liquid fatty alcohols; esters of fatty alcohols or liquid fatty acids; isononyl isononanoate; isostearyl malate; pentaerythrityl tetraisostearate; tridecyl trimelate; polybutene oil; or their mixtures. 45. The composition of claim 44 wherein the organic solvent (s) is (are) selected from silicones. 46. Use for the bleaching of keratin fibers of: at least one compound X and at least one compound Y as defined in any one of claims 1 and 4 to 33; at least one oxidizing agent as defined in any one of claims 1 and 34 to 38; and - optionally at least one organic solvent as defined in any one of claims 1, 44 and 45 and / or at least one alkaline agent as defined in any one of claims 1 and 40 to 42. 2910302 55 47 Kit for the bleaching of keratinous fibers comprising at least two compositions packaged separately, the kit comprising: at least one compound X and at least one compound Y as defined in any one of claims 1 and 4 to 33; At least one oxidizing agent as defined in any one of claims 1 and 34 to 38, and optionally at least one organic solvent as defined in any one of claims 1, 44 and 45 and / or at least one alkaline agent; as defined in any one of claims 1 and 40 to 42. 48. Composition for the bleaching of keratinous fibers comprising: - at least one compound X and at least one compound Y as defined in any one of the claims 1 and 4 to 33; at least two oxidizing agents different from one another as defined in any one of claims 1 and 34 to 38; and   - optionally at least one organic solvent as defined in any one of claims 1, 44 and 45 and / or at least one alkaline agent as defined in any one of claims 1 and 40 to 42. 49. Composition according to claim 48 wherein one of the oxidizing agents is selected from persulfates, perborates, ammonium or alkali metal percarbonates and the other is hydrogen peroxide.