Patent Publication Number: US-7220285-B2

Title: Pulverulent composition for bleaching human keratin fibers

Description:
This application is a continuation of the U.S. application Ser. No. 10/061,338 filed on Feb. 4, 2002 which is abandoned on May 1, 2006. 
    
    
     The present invention relates, to a pulverulent composition for bleaching human keratin fibers, such as the hair, comprising, in a medium that is suitable for bleaching, at least one peroxygenated salt, at least one polymer chosen from nonionic amphiphilic and anionic amphiphilic polymers comprising at least one fatty chain, and at least one polydecene of formula C 10n H [(20n)+2]  in which n ranges from 3 to 9, in an amount by weight of less than 10% relative to the total weight of the composition. 
     The invention also relates to the use of the pulverulent composition, or powder, for the preparation of a composition for bleaching human keratin fibers. Other aspects of the invention relate to a process for preparing the powder and to a process for bleaching keratin fibers by using the inventive composition. 
     Human keratin fibers, and more particularly the hair, are generally bleached by oxidizing the “melanin” pigments, resulting in the dissolution and partial or total removal of this pigment. 
     To bleach hair, it is known to use bleaching powders which may contain a peroxygenated reagent such as ammonium or alkali metal persulphates, perborates and percarbonates, and which are combined at the time of use with an aqueous hydrogen peroxide composition. 
     Because peroxygenated salts and hydrogen peroxide are relatively stable in acidic medium, it may often be necessary to activate them at basic pH to obtain an adequate formation of oxygen. It is thus common practice to add to bleaching powders alkaline compounds such as those chosen from urea, ammonium salts (ammonium chloride, sulphate, phosphate or nitrate), alkali metal silicates, alkaline-earth metal silicates, phosphates, and carbonates. For example, the alkaline compounds added to bleaching powders may be alkali metal metasilicates. 
     In haircare cosmetics, this aqueous hydrogen peroxide composition should not have a titre of more than 40 volumes. 
     However, in hairdressing salons, in order to increase the bleaching performance of pulverulent bleaching compositions, certain hair stylists might be tempted to use aqueous hydrogen peroxide solutions that are not formulated for cosmetic use and that have a titre of more than 40 volumes. These practices can be dangerous and could jeopardize the client&#39;s comfort and safety. 
     Thus, there remains a need for a novel bleaching powder which can be used with aqueous hydrogen peroxide compositions at volumes of less than 40 volumes. 
     It is known that bleaching powders have a tendency to form dust during their handling, transportation and storage. Given that the compounds of which bleaching powders are composed (alkali metal persulphates and silicates) may be corrosive and irritating to the eyes, the respiratory pathways and mucous membranes, it has been proposed to reduce the level of dust by depositing on the powder, by means of a spraying process, various compounds that are substantially insoluble in water, such as, for example, oils or liquid waxes, which, by coating the powder particles, aggregate them into particles of coarser size. European Patent EP 560 088 describes such a process. 
     To reduce the amount of dust, it has also been previously proposed to use liquid anhydrous polymers that are soluble in water at room temperature, such as those chosen from polyethylene glycols or polypropylene glycols (French patent No. 2 716 804), or block and/or random block linear polymers of the type such as polyoxyethylene/polyoxypropylene (European patent EP 663 205). 
     Moreover, in order to localize the bleaching product on the hair so that it does not run down the face or outside the areas that are intended to be bleached, it is common practice to thicken or gel the bleaching compositions with conventional thickeners such as water-soluble thickening polymers, for instance cellulose derivatives, starch derivatives, crosslinked polyacrylic acid or alginates or alternatively with thickening silicas. 
     Because these conventional thickeners may result in a fall in the viscosity of the bleaching compositions over time, it has been proposed, in French patent 2 788 974, to use a thickening system capable of maintaining a high viscosity for the time required to obtain the desired bleaching. This thickening system comprises a combination of a standard water-soluble thickener with a nonionic amphiphilic polymer comprising at least one fatty chain. 
     However, the bleaching treatment may often be corrosive and can lead to poor cosmetic properties of the hair, such as difficult disentangling, an unpleasant feel, coarse and dull hair, and degradation of the fibers. It has been proposed in French patent No 2 788 976 to significantly limit this degradation by using a combination of nonionic and/or anionic amphiphilic polymers and of cationic or amphoteric substantive polymers. 
     After considerable research conducted in this matter, the inventors have discovered a novel bleaching powder that is stable upon storage and that is capable of being mixed only with aqueous hydrogen peroxide compositions having a titre of not more than 40 volumes. The powder can form homogeneous, stable, ready-to-use bleaching compositions that are easy to apply, and that remain where applied without running or diffusing onto the areas of the hair that it is not desired to bleach. The compositions result in intense and homogeneous bleaching results without rendering the hair coarse. 
     The inventors have noted that mixtures of the bleaching powders according to the invention with aqueous hydrogen peroxide compositions having a titre of more than 40 volumes were heterogeneous and unstable, did not allow an easy or sufficiently precise application without running, and spread onto areas of the hair that were not intended to be bleached. Moreover, such compositions gave a heterogeneous hair bleaching effect and left the hair coarse. 
     The novel bleaching powder according to the present invention may, for example, be anhydrous. This powder may also be non-volatile, i.e., free of dust (or fines). Alternatively stated, the powder has a particle size distribution where the weight content of particles less than or equal to 65 microns in size (fines content) is generally less than or equal to 5%. In one embodiment, the weight content of such particles is less 2%, for example, less than 1%. 
     One embodiment of the present invention relates to a pulverulent composition for bleaching human keratin fibers, such as the hair, comprising, in a medium that is suitable for bleaching, at least one peroxygenated salt, at least one polymer chosen from nonionic amphiphilic and anionic amphiphilic polymers comprising at least one fatty chain, and at least one polydecene of formula C 10n H [(20n)+2]  , in which n ranges from 3 to 9, such as from 3 to 7, in an amount by weight of less than 10%, such as less than 5%, and for example, in an amount by weight ranging from 0.5% to 2% relative to the total weight of the composition. 
     Another embodiment of the relatesto a method for the preparation of a ready-to-use composition intended for bleaching human keratin fibers, such as the hair. The method comprises mixing, at the time of use, the inventive pulverulent composition with an aqueous hydrogen peroxide composition having a titre of not more than 40 volumes. 
     For the purposes of the present invention, the expression “ready-to-use composition” means the composition is intended to be applied in unmodified form to the keratin fibers, i.e., it results from the extemporaneous mixing of the powder and of the aqueous hydrogen peroxide composition. 
     For the purposes of the present invention, the term “anhydrous” means a powder whose water content is less than 5%, such as less than 1%, for example, less than 0.5% by weight. 
     Another subject of the invention is directed towards a process for bleaching human keratin fibers, and more particularly the hair, using the ready-to-use bleaching composition described above. 
     Another subject of the invention provides a method of preparing a pulverulent composition for bleaching human keratin fibers comprising mixing, at ambient temperature of about 25° C., at least one polydecene of formula C 10n H [(20n)+2]  in which n ranges from 3 to 9 with a mixture comprising at least one peroxygenated salt and at least one polymer chosen from nonionic and anionic amphiphilic polymers. Said at least one polymer comprises at least one fatty chain. 
     Another subject of the invention provides a multi-compartment device for bleaching human keratin fibers comprising at least two compartments. The device comprises a first compartment comprising a pulverulent composition comprising at least one peroxygenated salt, at least one polymer chosen from nonionic and anionic amphiphilic polymers comprising at least one fatty chain. and at least one polydecene of formula C 10n H [(20n)+2]  in which n ranges from 3 to 9, present in an amount by weight of less than 10% relative to the total weight of the composition. A second compartment comprises an aqueous hydrogen peroxide composition having a titre of not more than 40 volumes. 
     However, other characteristics, aspects and advantages of the invention will emerge even more clearly on reading the description and the examples which follow. 
     Nonionic Amphiphilic Polymers Comprising at least One Fatty Chain 
     Nonionic amphiphilic polymers comprising at least one fatty chain useful in the present invention may be chosen from, but are not limited to: 
     (1) celluloses modified with groups comprising at least one fatty chain, such as: 
     hydroxyethylcelluloses modified with groups comprising at least one fatty chain, such as alkyl, arylalkyl, alkylaryl groups, and mixtures thereof, and in which the alkyl groups may be C 8 –C 22 , such as the product Natrosol Plus Grade 330 CS® (C 16  alkyls) sold by the company Aqualon, or the product Bermocoll EHM 100® sold by the company Berol Nobel,
         celluloses modified with polyalkylene glycol alkylphenyl ether groups, such as the product Amercell Polymer HM-1500® (polyethylene glycol (15) nonylphenyl ether) sold by the company Amerchol;   (2) hydroxypropyl guars modified with groups comprising at least one C 8  to C 22  fatty chain, such as the product Jaguar® XC-95/3 (C 14  alkyl chain) sold by the company Rhodia, the product Esaflor® HM 22 (C 22  alkyl chain) sold by the company Lamberti, and the products RE210-18® (C 14  alkyl chain) and RE205-1® (C 20  alkyl chain) sold by the company Rhone-Poulenc;   (3) copolymers of vinylpyrrolidone and of hydrophobic monomers containing a fatty chain such as:   the products Antaron® V216 or Ganex® V216 (vinylpyrrolidone/hexadecene copolymer) sold by the company I.S.P.,   the products Antaron® V220 or Ganex® V220 (vinylpyrrolidone/eicosene copolymer) sold by the company I.S.P;   (4) copolymers of C 1 –C 6  alkyl acrylates, methacrylates and of amphiphilic monomers comprising at least one fatty chain;   (5) copolymers of hydrophilic acrylates, methacrylates and of hydrophobic monomers comprising at least one fatty chain, such as, for example, the polyethylene glycol methacrylate/lauryl methacrylate copolymer;   (6) polymers with an aminoplast ether skeleton containing at least one fatty chain, such as the Pure Thix® compounds sold by the company Sud-Chemie; and   (7) polyurethane polyethers comprising in their chain both hydrophilic blocks usually of polyoxyethylenated nature, and hydrophobic blocks that may be aliphatic sequences alone and/or cycloaliphatic and/or aromatic sequences.       

     In one embodiment, the polyurethane polyethers comprise at least two hydrocarbon-based lipophilic chains, containing from 6 to 30 carbon atoms, separated by a hydrophilic block, the hydrocarbon-based chains possibly being pendent chains or chains at the end of a hydrophilic block. In particular, it is possible for at least one of the pendent chains to be provided. In addition, the polymer may comprise a hydrocarbon-based chain at one or both ends of a hydrophilic block. 
     The polyurethane polyethers may be multiblock, such as in triblock form. The hydrophobic blocks may be at each end of the chain (for example: triblock copolymer containing a hydrophilic central block) or distributed both at the ends and in the chain (for example, a multiblock copolymer). These same polymers may also be graft polymers or starburst polymers. 
     The fatty-chain nonionic polyurethane polyethers may be triblock copolymers whose hydrophilic block comprises a polyoxyethylenated chain comprising from 50 to 1000 oxyethylenated groups. The nonionic polyurethane polyethers comprise a urethane bond between the hydrophilic blocks. 
     Also included among the fatty-chain nonionic polyurethane polyethers are those whose hydrophilic blocks are linked to the lipophilic blocks via other chemical bonds. 
     Non-limiting examples of fatty-chain nonionic polyurethane polyethers that may be used include Ser-Ad FX 1100® from the company Servo Delden, which is a copolymer known under the European and US INCI name “Steareth-100/PEG-136/HMDI Copolymer”. Rheolate® 205 containing a urea function, sold by the company Rheox, or alternatively Rheolate® 208, 204 or 212 or Acrysol® RM 184, may also be used. Mention may also be made of the product Elfacos® T210 containing a C 12-14  alkyl chain and the product Elfacos® T212 containing a C 18  alkyl chain, from Akzo. 
     The polyurethane polyethers that may be used are, for example, those described in the article by G. Fonnum, J. Bakke and F k. Hansen—Colloid Polym. Sci. 271, 380–389 (1993). 
     In one embodiment, polyurethane polyethers comprising at least one C 10  to C 20  fatty chain, and hydroxypropyl guars modified with groups comprising at least one C 8  to C 22  fatty chain, are used. 
     Anionic Amphiphilic Polymers Comprising at least One Fatty Chain 
     The anionic amphiphilic polymers comprising at least one fatty chain which may be used according to the present invention are polymers chosen from crosslinked and non-crosslinked polymers comprising
         hydrophilic units derived from at least one monomer containing ethylenic unsaturation bearing a free carboxylic acid function, or a free or partially or totally neutralized sulphonic function, and   hydrophobic units derived from at least one monomer containing ethylenic unsaturation bearing a hydrophobic side chain, and optionally   crosslinking units derived from at least one polyunsaturated monomer.       

     (A) The monomer(s) containing ethylenic unsaturation bearing a carboxylic acid function is(are) chosen from ethacrylic acid, methacrylic acid and acrylic acid, for example, from methacrylic acid and acrylic acid. 
     The monomer(s) containing ethylenic unsaturation bearing a hydrophobic side chain can be chosen from (i) fatty alkyl esters of unsaturated carboxylic acids, and (ii) allyl fatty alkyl ethers. 
     (i) The fatty alkyl esters of unsaturated carboxylic acids are chosen, for example, from C 10-30 , such as C 12-22 , alkyl ethacrylates, methacrylates, and acrylates. They encompass, for example, lauryl acrylate, stearyl acrylate, decyl acrylate, isodecyl acrylate and dodecyl acrylate, as well as the corresponding methacrylates, i.e., lauryl methacrylate, stearyl methacrylate, decyl methacrylate, isodecyl methacrylate and dodecyl methacrylate. 
     (ii) The allyl fatty alkyl ethers forming the hydrophobic units of the anionic amphiphilic polymers correspond to the formula
 
CH 2 ═CR′CH 2 OB n R  (I)
 
     in which R′ is chosen from a hydrogen atom and CH 3 , B is an ethylenoxy group, n is chosen from 0 or an integer from 1 to 100, R is a hydrocarbon-based group chosen from alkyl, arylalkyl, aryl, alkylaryl and cycloalkyl radicals comprising from 8 to 30 carbon atoms, such as from 10 to 24 carbon atoms, and for example from 12 to 18 carbon atoms. In one embodiment, R′ is a hydrogen atom, n is equal to 10 and R is a stearyl (C 18 ) radical. 
     The monomer from which the cross-linking Units are derived is a compound comprising at least two non-conjugated polymerizable double bonds. Examples which may be mentioned are diallyl phthalate, allyl(meth)acrylate, divinylbenzene, (poly)ethylene glycol dimethacrylate, methylenebisacrylamide, polyallylsucrose and polyallylpentaerythritol. 
     Anionic amphiphilic polymers of the type described above are described and prepared, for example, in U.S. Pat. Nos. 3,915,921 and 4,509,949 (copolymers of (meth)acrylic acid and of C 10-30  alkyl (meth)acrylates), or in European patent EP-0 216 479 B2 (copolymers of (meth)acrylic acid and of allyl fatty alcohol ethers), the disclosure of which are herein incorporated by reference. 
     In some embodiment, the polymers used may be chosen from, but are not limited to: 
     crosslinked polymers of acrylic acid and of C 10-30  alkyl methacrylate, such as Carbopol® ETD 2020 sold by the company Goodrich; 
     crosslinked polymers of acrylic acid and of C 10-30  alkyl acrylate, such as the polymers sold under the names Carbopol® 1382, Pemulen® TR1 and Pemulen® TR2 by the company Goodrich; 
     methacrylic acid/ethyl acrylate/oxyethylenated stearyl methacrylate (55/35/10) terpolymer; 
     (meth)acrylic acid/ethyl acrylate/25 EO oxyethylenated behenyl methacrylate terpolymer, and 
     methacrylic acid/ethyl acrylate/steareth-10 allyl ether crosslinked terpolymer. 
     (B) The amphiphilic polymers comprising, as hydrophilic units, at least one ethylenically unsaturated monomer containing a sulphonic group, in free or partially or totally neutralized form, and at least one hydrophobic portion, are described, for example, in French patent applications 0 016 954 and 0 100 328, the disclosures of which are hereby incorporated by reference. Examples of such amphiphilic polymers include: 
     2-acrylamido-2-methylpropanesulphonic acid (AMPS)/n-dodecylacrylamide copolymer neutralized with sodium hydroxide, the copolymer crosslinked with methylenebisacrylamide comprising 75% by weight of AMPS units neutralized with NH 3  and 25% by weight of acrylate units of Genapol® T-250, the copolymer crosslinked with allyl methacrylate comprising 90% by weight of AMPS units neutralized with NH 3  and 10% by weight of methacrylate units of Genapol® T-250, or the crosslinked copolymer of allyl methacrylate comprising 80% by weight of AMPS units neutralized with NH 3  and 20% by weight of methacrylate units of Genapol® T-250. 
     In the bleaching powder according to the present invention, the nonionic and/or anionic amphiphilic polymer(s) comprising at least one fatty chain may be present in an amount by weight ranging from 0.01% to 30%, such as from 0.01% to 15%, relative to the total weight of the bleaching powder. 
     Polydecenes of Formula C 10n H [(20n)+2]  with n Ranging from 3 to 9 
     These compounds correspond to the name “polydecene” in the CTFA Dictionary, 7th edition (1997), of the Cosmetic, Toiletry and Fragrance Association, USA, and also to the same INCI name in the USA and in Europe. They are products of hydrogenation of poly-1-decenes. In one embodiment, n ranges from 3 to 7. Mention may be made, by way of example, of the product sold under the name Silkflo® 366 NF Polydecene by the company Amoco Chemical. 
     In the bleaching powder according to the invention, the polydecene(s) may be present in an amount by weight of less than 10% relative to the total weight of the non-volatile powder, such as less than 5%, for example, ranging from 0.5% to 2%. 
     Peroxygenated Salts 
     Examples of peroxygenated salts useful in the present invention include, but are not limited to, ammonium and alkali metal persulphates, perborates and percarbonates and also from magnesium peroxide, and mixtures of these compounds. 
     In one embodiment, persulphates are used, such as sodium and potassium persulphates. 
     In the bleaching powder according to the invention, the peroxygenated salt(s) may be present in an amount by weight ranging from 20% to 70%, such as from 30% to 60% relative to the total weight of the said powder. 
     Alkaline Agents 
     Alkaline agents such as those chosen from urea, alkali metal and alkaline-earth metal silicates, phosphates and carbonates, alkali metal metasilicates, and ammonia precursors such as ammonium salts, may be present in the anhydrous bleaching powder in an amount by weight ranging from 0.01% to 40%, such as from 0.1% to 30% relative to the total weight of the bleaching powder. According to one embodiment, they may be present in an aqueous composition to be mixed at the time of use with the aqueous hydrogen peroxide composition. 
     Water-Soluble Thickening Polymers 
     In addition, the bleaching powder according to the invention may also contain water-soluble thickening polymers. These polymers encompass any water-soluble polymer that is synthetic or of natural origin, conventionally used in the cosmetic field, and are polymers other than the nonionic and/or anionic amphiphilic polymers comprising at least one fatty chain, as described previously. 
     Useful synthetic polymers include, but are not limited to, polyvinylpyrrolidone, polyacrylic acid, polyacrylamide, non-crosslinked poly-2-acrylamidopropanesulphonic acid such as, for example, the product sold under the name Simugel EG® by the company SEPPIC, crosslinked poly-2-acrylamido-2-methylpropanesulphonic acid, poly-2-acrylamido-2-methylpropanesulphonic acid crosslinked and partially neutralized with aqueous ammonia, sold under the brand name Hostacerin AMPS® by the company Clariant, mixtures with a synergistic thickening effect of the non-crosslinked poly-2-acrylamido-2-methylpropanesulphonic acid with hydroxylalkylcellulose ethers or with poly(ethylene oxide) as described in U.S. Pat. No. 4,540,510, the disclosure of which is hereby incorporated by reference, mixtures with a synergistic thickening effect of a poly(meth)acrylamido(C 1 –C 4 )alkylsulphonic acid, which may be crosslinked with a crosslinked copolymer of maleic anhydride, and of a (C 1 –C 5 )alkyl vinyl ether such as the mixture Hostacerin AMPS®/Stabileze QM® (from the company ISP) and as described in French patent application number 0 014 416, the disclosure of which is hereby incorporated by reference. 
     The thickening polymers of natural origin may be polymers comprising at least one sugar unit, such as, but not limited to: nonionic guar gums; biopolysaccharide gums of microbial origin such as scleroglucan gum and xanthan gum; gums derived from plant exudates, such as gum arabic, ghatti gum, karaya gum, gum tragacanth, carrageenan, agar and carob gum; pectins; alginates; starches; hydroxy(C 1 –C 6 )alkylcelluloses and carboxy(C 1 –C 6 )alkylcelluloses. 
     For purposes of the present invention, the expression “sugar unit” denotes a portion chosen from monosaccharide portions (i.e., monosaccharides, osides and simple sugars) and oligosaccharide portions (short chains formed from the linking of monosaccharide units, which may be different) or a polysaccharide portion (long chains comprising monosaccharide units, which may be different, i.e., polyholosides and polyosides (homopolyosides and heteropolyosides)). The saccharide units can also be substituted with groups chosen from alkyl, hydroxyalkyl, alkoxy, acyloxy groups, carboxyl groups, and alkyl radicals containing from 1 to 4 carbon atoms. 
     The nonionic guar gums can be modified or unmodified. The unmodified guar gums may be chosen from, for example, the products sold under the name Guargel® D/15 by the company Goodrich, Vidogum GH 175 by the company Unipectine and under the names Meypro-Guar 50® and Jaguar® C by the company Meyhall. 
     The modified nonionic guar gums are especially modified with C 1 –C 6  hydroxyalkyl groups. Among the hydroxyalkyl groups which may be mentioned, for example, are hydroxymethyl, hydroxyethyl, hydroxypropyl and hydroxybutyl groups. These guar gums are well known in the state of the art and can be prepared, for example, by reacting the corresponding alkene oxides such as, for example, propylene oxides, with the guar gum so as to obtain a guar gum modified with hydroxypropyl groups. The degree of hydroxyalkylation, which corresponds to the number of alkylene oxide molecules consumed by the number of free hydroxyl functions present on the guar gum, in one embodiment, ranges from 0.4 to 1.2. 
     Such nonionic guar gums optionally modified with hydroxyalkyl groups are sold, for example, under the trade names Jaguar® HP8, Jaguar® HP60 and Jaguar® HP120, Jaguar® DC 293 and Jaguar® HP 105 by the company Rhône-Poulenc (Meyhall) or under the name Galactasol® 4H4FD2 by the company Aqualon. 
     The biopolysaccharide gums of microbial origin, such as the scleroglucan and xanthan gums, the gums derived from plant exudates such as gum arabic, ghatti gum, karaya gum, gum tragacanth, carrageenan gum, agar gum and carob gum, the hydroxyalkylcelluloses and carboxymethylcelluloses, pectins, alginates and starches are well known to those skilled in the art and are described for example in the book by Robert L. Davidson entitled “Handbook of Water Soluble Gums and Resins,” published by McGraw Hill Book Company (1980). 
     Among these gums, the scleroglucans are represented by the products sold under the name Actigum® CS by the company Sanofi Bio Industries and in particular Actigum® CS 11, and under the name Amigel® by the company Alban Muller International. Other scleroglucans, such as the one treated with glyoxal in French patent application No. 2 633 940, the disclosure of which is hereby incorporated by reference, can also be used. 
     The xanthans are represented by the products sold under the names Keltrol®, Keltrol® T, Keltrol® TF, Keltrol® BT, Keltrol® RD and Keltrol® CG by the company Nutrasweet Kelco, or under the names Rhodicare® S and Rhodicare® H by the company Rhodia Chimie. 
     Among the starch derivatives that may be mentioned, for example, is the product sold under the name Primogel® by the company Avebe. 
     The hydroxy(C 1 –C 6 )alkylcelluloses may, in one embodiment, be hydroxyethylcelluloses, such as those sold under the names Cellosize® QP3L, Cellosize® QP4400 H, Cellosize® QP30000H, Cellosize® HEC30000A and Cellosize® Polymer PCG10 by the company Amerchol, or Natrosol® 250HHR, Natrosol® 250 MR, Natrosol® 250M, Natrosol® 250HHXR, Natrosol® 250HHX, Natrosol® 250HR and Natrosol® HX by the company Hercules, or Tylose® H1000 by the company Hoechst. The hydroxy(C 1 –C 6 )alkylcelluloses may also be hydroxypropylcelluloses such as the products sold under the names Klucel® EF, Klucel® H, Klucel® LHF, Klucel® MF and Klucel® G by the company Aqualon. 
     Among the carboxy(C 1 –C 6 )alkylcelluloses useful in the invention is, for example, carboxymethylcellulose, for which mention may be made of the products sold under the names Blanose® 7M8/SF, Blanose® Raffinée 7M, Blanose® 7LF, Blanose® 7MF, Blanose ® 9M31F, Blanose® 12M31XP, Blanose® 12M31P, Blanose® 9M31XF, Blanose® 7H, Blanose® 7M31 and Blanose® 7H3SXF by the company Aqualon, or Aquasorb® A500 and Ambergum® 1221 by the company Hercules, or Cellogen® HP810A and Cellogen® HP6HS9 by the company Montello, or Primellose® by the company Avebe. 
     When they are present in the pulverulent compositions of the present invention, the water-soluble thickening polymers can be present in an amount by weight of less than or equal to 5% relative to the total weight of the composition, such as less than or equal to 3%. 
     Other Adjuvants 
     To prevent the anhydrous bleaching powder of the invention from being degraded by ambient moisture during storage, it is possible to add thereto moisture absorbers such as, for example, silicas, for instance colloidal silica, or fumed silica of hydrophobic or hydrophilic nature, in an amount by weight of less than or equal to 3% relative to the total weight of the bleaching powder. 
     The bleaching powder according to the invention may also contain fillers such as those chosen from clays, binders such as vinylpyrrolidone, lubricants such as polyol stearates, alkali metal stearates, and alkaline-earth metal stearates, and also agents for controlling the evolution of oxygen, such as magnesium carbonate and magnesium oxide, colorants and matt-effect agents such as titanium oxides, and alternatively surfactants chosen from anionic, nonionic and amphoteric surfactants. 
     The bleaching powder may also contain polymers chosen from anhydrous cationic and amphoteric conditioning polymers that are well known to those skilled in the art and that are described in French patents Nos. 2 788 974 and 2 788 976 and as described below. 
     Cationic Polymers 
     As used herein, the expression “cationic polymer” denotes any polymer containing cationic groups and/or groups which may be ionized into cationic groups. 
     The cationic polymers may be chosen from any of those already known as improving the cosmetic properties of the hair, such as those described in European patent application EP-A-337 354 and in French patents FR-2 270 846, 2 383 660, 2 598 611, 2 470 596 and 2 519 863, the disclosures of all which are hereby incorporated by reference. 
     The cationic polymers may, for example, be chosen from those containing units comprising primary, secondary, tertiary and/or quaternary amine groups, which may either form part of the main polymer chain or may be borne by a side substituent directly attached thereto. 
     The cationic polymers used generally have a number-average molecular mass ranging from 500 to 5×10 6 , such as from 10 3  to 3×10 6 . 
     Among the cationic polymers which may be mentioned, for example, are polyamine, polyaminoamide and polyquaternary ammonium polymers. These polymers are described in French patents Nos. 2 505 348 and 2 542 997, the disclosures of which are hereby incorporated by reference. Examples of such polymers include, but are not limited to: 
     (1) homopolymers or copolymers derived from acrylic or methacrylic esters or amides and comprising at least one of the units of formula (I), (II), (III) or (IV) below: 
                         
in which:
 
     R 3 , which may be identical or different, is chosen from a hydrogen atom and a CH 3  radical; 
     A, which may be identical or different, is chosen from linear and branched alkyl groups of 1 to 6 carbon atoms, such as 2 or 3 carbon atoms, and hydroxyalkyl groups of 1 to 4 carbon atoms; 
     R 4 , R 5  and R 6 , which may be identical or different, are chosen from alkyl groups containing from 1 to 18 carbon atoms and benzyl radicals, such as an alkyl group containing from 1 to 6 carbon atoms; 
     R 1  and R 2 , which may be identical or different, are chosen from hydrogen and an alkyl group containing from 1 to 6 carbon atoms, such as methyl or ethyl; 
     X is an anion derived from an inorganic or organic acid, such as a methosulphate anion, or a halide such as chloride or bromide. 
     Copolymers of family (1) can also contain at least one unit derived from comonomers which may be chosen from the family of acrylamides, methacrylamides, diacetone acrylamides, acrylamides and methacrylamides substituted on the nitrogen with lower (C 1 –C 4 ) alkyls, acrylic acids, methacrylic acids, acylic esters, methacrylic esters, vinyllactams such as vinylpyrrolidone or vinylcaprolactam, and vinyl esters. 
     Thus, among these polymers of family (1), mention may be made of:
         copolymers of acrylamide and of dimethylaminoethyl methacrylate quaternized with dimethyl sulphate or with a dimethyl halide;   the copolymers of acrylamide and of methacryloyloxyethyltrimethylammonium chloride described, for example, in patent application EP-A-080 976, the disclosure of which is hereby incorporated by reference;   the copolymer of acrylamide and of methacryloyloxyethyltrimethylammonium methosulphate;   quaternized or non-quaternized vinylpyrrolidone/dialkylaminoalkyl acrylate or methacrylate copolymers, as described in detail in French patents 2 077 143 and 2 393 573, the disclosures of which are hereby incorporated by reference;   dimethylaminoethyl methacrylate/vinylcaprolactam/vinylpyrrolidone terpolymers;   vinylpyrrolidone/methacrylamidopropyldimethylamine copolymers; and   quaternized vinylpyrrolidone/dimethylaminopropylmethacrylamide copolymers.       

     (2) The cellulose ether derivatives containing quaternary ammonium groups, described in French patent 1 492 597, which is hereby incorporated by reference. These polymers are also defined in the CTFA dictionary as quaternary ammoniums of hydroxyethylcellulose which has reacted with an epoxide substituted with a trimethylammonium group. 
     (3) Cationic cellulose derivatives such as cellulose copolymers or cellulose derivatives grafted with a water-soluble monomer of quaternary ammonium, and described, for example, in U.S. Pat. No. 4,131,576, which is hereby incorporated by reference, such as hydroxyalkylcelluloses, chosen, for instance from hydroxymethyl-, hydroxyethyl- and hydroxypropylcelluloses grafted, for example, with a salt chosen from methacryloylethyltrimethylammonium, methacrylamidopropyltrimethylammonium and dimethyldiallylammonium salts. 
     (4) The cationic polysaccharides described, for instance in U.S. Pat. Nos. 3,589,578 and 4,031,307, the disclosures of which are hereby incorporated by reference, such as guar gums containing cationic trialkylammonium groups. Guar gums modified with a salt (e.g., chloride) of 2,3-epoxypropyltrimethylammonium are used, for example. 
     (5) Polymers comprising piperazinyl units and of divalent alkylene or hydroxyalkylene radicals containing straight or branched chains, optionally interrupted by a heteroatom such as oxygen, sulphur and nitrogen, or by aromatic or heterocyclic rings, as well as the oxidation and/or quaternization products of these polymers. Such polymers are described, in particular, in French patents 2 162 025 and 2 280 361, the disclosures of which are hereby incorporated by reference; 
     (6) Water-soluble polyaminoamides prepared in particular by polycondensation of an acidic compound with a polyamine; these polyaminoamides can be crosslinked with an epihalohydrin, a diepoxide, a dianhydride, an unsaturated dianhydride, a bis-unsaturated derivative, a bis-halohydrin, a bis-azetidinium, a bis-haloacyldiamine, a bis-alkyl halide or alternatively with an oligomer resulting from the reaction of a difunctional compound which is reactive with a bis-halohydrin, a bis-azetidinium, a bis-haloacyldiamine, a bis-alkyl halide, an epihalohydrin, a diepoxide or a bis-unsaturated derivative. The crosslinking agent is used in proportions ranging from 0.025 to 0.35 mol per amine group of the polyaminoamide. These polyaminoamides can be alkylated or, if they contain at least one tertiary amine function, they can be quaternized. Such polymers are described, in particular, in French patents 2 252 840 and 2 368 508, the disclosures of which are hereby incorporated by reference. 
     (7) The polyaminoamide derivatives resulting from the condensation of polyalkylene polyamines with polycarboxylic acids followed by alkylation with difunctional agents. Mention may be made, for example, of adipic acid/dialkylaminohydroxyalkyldialkylenetriamine polymers in which the alkyl radical contains from 1 to 4 carbon atoms, such as denotes methyl, ethyl or propyl. Such polymers are described in particular in French patent 1 583 363, which is hereby incorporated by reference. 
     Among these derivatives, mention may be made more particularly of the adipic acid/dimethylaminohydroxypropyl/diethylenetriamine polymers. 
     (8) The polymers obtained by reaction of a polyalkylene polyamine containing two primary amine groups and at least one secondary amine group with a dicarboxylic acid chosen from diglycolic acid and saturated aliphatic dicarboxylic acids having from 3 to 8 carbon atoms. The molar ratio between the polyalkylene polyamine and the dicarboxylic acid ranges, for example, from 0.8:1 to 1.4:1; the polyaminoamide resulting therefrom is reacted with epichlorohydrin in a molar ratio of epichlorohydrin relative to the secondary amine group of the polyaminoamide ranging from 0.5:1 to 1.8:1. Such polymers are described in particular in U.S. Patent Nos. 3,227,615 and 2, 961,347, the disclosures of which are hereby incorporated by reference. 
     (9) Cyclopolymers of alkyldiallylamine or of dialkyldiallylammonium, such as the homopolymers or copolymers containing, as main constituent of the chain, units corresponding to formula (V) or (VI): 
                         
wherein k and t are equal to 0 or 1, the sum k+t being equal to 1;
 
     R 9  is chosen from a hydrogen atom and a methyl radical; 
     R 7  and R 8 , independently of each other, are chosen from an alkyl group having from 1 to 8 carbon atoms, a hydroxyalkyl group in which the alkyl group may, in one embodiment, have 1 to 5 carbon atoms, and a lower C 1 –C 4  amidoalkyl group, or R 7  and R 8  can denote, together with the nitrogen to which they are attached, heterocyclic groups such as piperidyl or morpholinyl; in one embodiment, R 7  and R 8 , independently of each other, may be chosen from alkyl groups having from 1 to 4 carbon atoms; Y −  is an anion such as bromide, chloride, acetate, borate, citrate, tartrate, bisulphate, bisulphite, sulphate, and phosphate. These polymers are described in particular in French patent 2 080 759 and in its Certificate of Addition 2 190 406, the disclosures of which are hereby incorporated by reference. 
     (10) The quaternary diammonium polymer containing repeating units corresponding to the formula (VII): 
                         
in which:
 
     R 13 , R 14 , R 15  and R 16 , which may be identical or different, are chosen from aliphatic, alicyclic and arylaliphatic radicals containing from 1 to 20 carbon atoms and from lower hydroxyalkylaliphatic radicals, or alternatively R 13 , R 14 , R 15  and R 16 , together or separately, constitute, with the nitrogen to which they are attached, heterocycles optionally containing a second heteroatom other than nitrogen, or alternatively R 13 , R 14 , R 15  and R 16  are chosen from linear and branched C 1 –C 6  alkyl radicals substituted with groups chosen from nitrile, ester, acyl and amide groups, and a group —CO—O—R 14 —D or —CO—NH—R 14 —D where R 14  is an alkylene and D is a quaternary ammonium group; 
     A 1  and B 1 , which may be identical or different, are chosen from linear and branched, saturated and unsaturated polymethylene groups containing from 2 to 20 carbon atoms, and which may contain, linked to or intercalated in the main chain, at least one entity chosen from aromatic rings, oxygen, sulphur, sulphoxide, and a group chosen from sulphone, disulphide, amino, alkylamino, hydroxyl, quaternary ammonium, ureido, amide, and ester, and 
     X −  is an anion derived from an inorganic or organic acid; 
     A 1 , R 13  and R 15  can form, with the two nitrogens to which they are attached, a piperazine ring. In addition, if A 1  is a radical chosen from linear and branched, saturated and unsaturated alkylene and hydroxyalkylene radicals, B 1  can also denote a group—(CH 2 ) n —CO—D—OC—(CH 2 ) n — in which n is from 1 to 100, such as from 1 to 50, and D is chosen from: 
     a) a glycol residue of formula: —O—Z—O—, where Z is chosen from linear and branched hydrocarbon-based radicals and a group corresponding to one of the following formulae:
 
—(CH 2 —CH 2 —O) x —CH 2 —CH 2 —
 
—[CH 2 —CH(CH 3 )—O] y —CH 2 —CH(CH 3 )—
 
     where x and y are each an integer from 1 to 4, representing a defined and unique degree of polymerization or any number from 1 to 4 representing an average degree of polymerization; 
     b) a bis-secondary diamine residue such as a piperazine derivative; 
     c) a bis-primary diamine residue of formula: —NH—Y—NH—, where Y is chosen from linear and branched hydrocarbon-based radicals, or alternatively the divalent radical
 
—CH 2 —CH 2 —S—S—CH 2 —CH 2 —; or
 
     d) a ureylene group of formula: —NH—CO—NH—. 
     In one embodiment, X −  is an anion such as chloride or bromide. 
     These polymers generally have a number-average molecular mass ranging from 1000 to 100,000. 
     Polymers of this family are described in particular in French patents 2 320 330, 2 270 846, 2 316 271, 2 336 434 and 2 413 907 and U.S. Pat. Nos. 2,273,780, 2,375,853, 2,388,614, 2,454,547, 3,206,462, 2,261,002, 2,271,378, 3,874,870, 4,001,432, 3,929,990, 3,966,904, 4,005,193, 4,025,617, 4,025,627, 4,025,653, 4,026,945 and 4,027,020, the disclosures of which are hereby incorporated by reference. 
     Other exemplary polymers of family (10) can comprise repeating units corresponding to the following formula (VIII): 
                         
in which R 10 , R 11 , R 12  and R 13 , which may be identical or different, are chosen from alkyl and hydroxyalkyl radicals containing from 1 to 4 carbon atoms, n and p are integers ranging from 2 to 20, and X −  is an anion derived from an inorganic or organic acid.
 
     (11) Polyquaternary ammonium polymers comprising repeating units of formula (IX): 
                         
in which p is an integer ranging from 1 to 6, D may be a bond or may be a group —(CH 2 ) r —CO— in which r is a number equal to 4 or 7, X −  is an anion;
 
     Such polymers may be prepared according to the processes described in U.S. Pat. Nos. 4,157,388, 4,702,906 and 4,719,282, the disclosures of which are hereby incorporated by reference. They are described, for example, in European patent application EP-A-122 324, which is hereby incorporated by reference. 
     (12) Quaternary polymers of vinylpyrrolidone and of vinylimidazole. 
     (13) Polyamines such as the product which is referenced to under the name “Polyethylene glycol (15) Tallow polyamine” in the CTFA dictionary. 
     (14) Crosslinked methacryloyloxy(C 1 –C 4 )alkyltri(C 1 –C 4 )alkylammonium salt polymers such as the polymers obtained by homopolymerization of dimethylaminoethyl methacrylate quaternized with methyl chloride, or by copolymerization of acrylamide with dimethylaminoethyl methacrylate quaternized with methyl chloride, the homo- or copolymerization being followed by crosslinking with a compound containing olefinic unsaturation, such as methylenebisacrylamide. A crosslinked acrylamide/methacryloyloxyethyltrimethylammonium chloride copolymer (20/80 by weight) in the form of a dispersion containing 50% by weight of the copolymer in mineral oil can be used, in one embodiment. This dispersion is sold under the name “Salcare® SC 92” by the company Allied Colloids. A crosslinked methacryloyloxyethyltrimethylammonium chloride homopolymer containing 50% by weight of the homopolymer in mineral oil or in a liquid ester can also be used. These dispersions are sold under the names “Salcare® SC 95” and “Salcare® SC 96” by the company Allied Colloids. 
     Other cationic polymers which can be used include polyalkyleneimines, such as polyethyleneimines, polymers containing vinylpyridine or vinylpyridinium units, condensates of polyamines and of epichlorohydrin, quaternary polyureylenes and chitin derivatives. 
     Amphoteric Polymers 
     The amphoteric polymers useful in the present invention, may be chosen from polymers comprising units K and M randomly distributed in the polymer chain, in which K is a unit derived from a monomer comprising at least one basic nitrogen atom and M is a unit derived from an acidic monomer comprising at least one carboxylic or sulphonic group, or alternatively K and M may be chosen from groups derived from zwitterionic carboxybetaine or sulphobetaine monomers; 
     K and M may also be chosen from a cationic polymer chain comprising a group chosen from at least one primary, secondary, tertiary and quaternary amine group, in which at least one of the amine groups bears a carboxylic or sulphonic group linked via a hydrocarbon-based radical, or alternatively K and M form part of a chain of a polymer containing an α,β-dicarboxylic ethylene unit in which one of the carboxylic groups has been made to react with a polyamine comprising at least one primary or secondary amine group. 
     The amphoteric polymers corresponding to the above definition can be chosen from the following polymers: 
     (1) polymers resulting from the copolymerization of a monomer derived from a vinyl compound bearing a carboxylic group, such as acrylic acid, methacrylic acid, maleic acid, α-chloroacrylic acid, and a basic monomer derived from a substituted vinyl compound containing at least one basic atom, such as dialkylaminoalkyl methacrylate and acrylate, dialkylaminoalkylmethacrylamide and -acrylamide. Such compounds are described in U.S. Pat. No. 3,836,537, which is hereby incorporated by reference. Mention may also be made of the sodium acrylate/acrylamidopropyltrimethylammonium chloride copolymer. 
     The vinyl compound may also be a dialkyldiallylammonium salt such as dimethyldiallylammonium chloride. 
     (2) polymers containing units derived from: 
     a) at least one monomer chosen from acrylamides and methacrylamides substituted on the nitrogen with an alkyl radical, 
     b) at least one acidic comonomer containing at least one reactive carboxylic group, and 
     c) at least one basic comonomer such as esters containing primary, secondary, tertiary and quaternary amine substituents of acrylic and methacrylic acids and the product of quaternization of dimethylaminoethyl methacrylate with dimethyl or diethyl sulphate. 
     In one embodiment, the N-substituted acrylamides or methacrylamides which can be used include groups in which the alkyl radicals contain from 2 to 12 carbon atoms, such as N-ethylacrylamide, N-tert-butylacrylamide, N-tert-octylacrylamide, N-octylacrylamide, N-decylacrylamide, N-dodecylacrylamide and the corresponding methacrylamides. 
     The acidic comonomers may be chosen, for example, from acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid and fumaric acid and alkyl monoesters, having 1 to 4 carbon atoms, of maleic or fumaric acids or anhydrides. 
     The preferred basic comonomers are aminoethyl, butylaminoethyl, N,N′-dimethylaminoethyl and N-tert-butylaminoethyl methacrylates. 
     (3) crosslinked and alkylated polyaminoamides partially or totally derived from polyaminoamides of formula: 
                         
in which R 19  is chosen from a divalent radical derived from a saturated dicarboxylic acid, a mono- or dicarboxylic aliphatic acid containing an ethylenic double bond, an ester of a lower alkanol, having 1 to 6 carbon atoms, of these acids or a radical derived from the addition of any one of the said acids to a bis(primary) or bis(secondary) amine, and Z is chosen from a bis(primary), mono- or bis(secondary) polyalkylene-polyamine radical, such as:
 
     a) in proportions of from 60 to 100 mol %, the radical 
                         
where x=2 and p=2 or 3, or alternatively x=3 and p=2, this radical being derived from diethylenetriamine, triethylenetetraamine or dipropylenetriamine;
 
     b) in proportions of from 0 to 40 mol %, the radical (XI) above in which x=2 and p=1 and which can be derived from ethylenediamine, or piperazine: 
     
       
         
         
             
             
         
       
     
     c) in proportions of from 0 to 20 mol %, the —NH—(CH 2 ) 6 —NH— radical, which can be derived from hexamethylenediamine, these polyaminoamines can be crosslinked by addition of a difunctional crosslinking agent chosen from epihalohydrins, diepoxides, dianhydrides and bis-unsaturated derivatives, using from 0.025 to 0.35 mol of crosslinking agent per amine group of the polyaminoamide and alkylated by the action of acrylic acid, chloroacetic acid or an alkane sultone, or salts thereof. 
     In one embodiment, the saturated carboxylic acids are chosen from acids having 6 to 10 carbon atoms, such as adipic acid, 2,2,4-trimethyladipic acid and 2,4,4-trimethyladipic acid, terephthalic acid and acids containing an ethylenic double bond such as, for example, acrylic acid, methacrylic acid and itaconic acid. 
     The alkane sultones used in the alkylation may be chosen from propane sultone and butane sultone, and the salts of the alkylating agents may be chosen from sodium and potassium salts. 
     (4) polymers containing zwitterionic units of formula: 
                         
in which R 20  is chosen from a polymerizable unsaturated group such as an acrylate, methacrylate, acrylamide or methacrylamide group; y and z are chosen from an integer ranging from 1 to 3;
 
     R 21  and R 22  are chosen from hydrogen atom, methyl, ethyl and propyl; 
     R 23  and R 24  are chosen from a hydrogen atom and an alkyl radical such that the sum of the carbon atoms in R 23  and R 24  does not exceed 10. 
     The polymers comprising such units can also contain units derived from non-zwitterionic monomers such as dimethyl or diethylaminoethyl acrylate or methacrylate or alkyl acrylates or methacrylates, acrylamides or methacrylamides or vinyl acetate. 
     By way of example, mention may be made of the copolymer of butyl methacrylate/dimethyl carboxymethylammonio ethyl methacrylate such as the product sold under the name Diaformer Z301 by the company Sandoz. 
     (5) polymers derived from chitosan containing monomer units corresponding to formulae (XIII), (XIV) and (XV) below: 
                         
the unit (XIII) being present in proportions ranging from 0 to 30%, the unit (XIV) in proportions ranging from 5 to 50% and the unit (XV) in proportions ranging from 30 to 90%, where in unit (XV), R 25  represents a radical of the formula:
 
                         
in which q is 0 or 1;
 
     if q=0, R 26 , R 27  and R 28 , which may be identical or different, each are chosen from a hydrogen atom, a methyl, hydroxyl, acetoxy and amino residue, a monoalkylamine residue and a dialkylamine residue which are optionally interrupted by at least one nitrogen atom and/or optionally substituted with at least one group chosen from amine, hydroxyl, carboxyl, alkylthio, and sulphonic groups, and an alkylthio residue in which the alkyl group bears an amino residue, at least one of the radicals R 26 , R 27  and R 28  being, in this case, a hydrogen atom; 
     or, if q=1, R 26 , R 27  and R 28  each are a hydrogen atom, as well as the salts formed by these compounds with bases or acids. 
     6) polymers derived from the N-carboxyalkylation of chitosan, such as N-carboxymethylchitosan and N-carboxybutylchitosan. 
     7) polymers corresponding to the general formula (XVI) as described, for example, in French patent 1 400 366, which is hereby incorporated by reference: 
                         
in which R 29  is chosen from a hydrogen atom, a CH 3 O, CH 3 CH 2 O and a phenyl radical,
 
     R 30  is chosen from hydrogen and a lower alkyl radical such as methyl or ethyl, 
     R 31  is chosen from hydrogen and a lower alkyl radical such as methyl or ethyl, 
     R 32  is chosen from a lower alkyl radical such as methyl or ethyl and a radical corresponding to the formula: —R 33 —N(R 31 ) 2 , 
     R 33  is chosen from —CH 2 —CH 2 —, —CH 2 —CH 2 —CH 2 — and —CH 2 —CH(CH 3 )— groups, 
     R 31  having the meanings mentioned above, as well as the higher homologues of these radicals and containing up to 6 carbon atoms, 
     r is such that the molecular weight ranges from 500 to 6 000 000, for example ranges from 1000 to 1 000 000. 
     8) amphoteric polymers of the type —D—X—D—X— chosen from: 
     a) polymers obtained by the action of chloroacetic acid or sodium chloroacetate on compounds containing at least one unit of formula:
 
—D—X—D—X—D—  (XVII)
 
where D is a radical
 
                         
and X is the symbol E or E′,
 
     E or E′, which may be identical or different, are chosen from a divalent radical which is an alkylene radical with a straight or branched chain containing up to 7 carbon atoms in the main chain, which is unsubstituted or substituted with hydroxyl groups; 
     E or E′ can optionally contain groups chosen from: heteroatoms chosen from oxygen, nitrogen and sulphur atoms; and 1 to 3 aromatic and/or heterocyclic rings. The oxygen, nitrogen and sulphur atoms can be present in the form of groups chosen from ether, thioether, sulphoxide, sulphone, sulphonium, alkylamine, alkenylamine, hydroxyl, benzylamine, amine oxide, quaternary ammonium, amide, imide, alcohol, ester and urethane groups; 
     b) polymers of formula:
 
—D—X—D—X—  (XVIII)
 
where D denotes a radical
 
     
       
         
         
             
             
         
       
     
     and X denotes the symbol E or E′ and at least once E′; E having the meaning given above and E′ being a divalent radical chosen from alkylene radicals with a straight or branched chain having up to 7 carbon atoms in the main chain, which is unsubstituted or substituted with at least one hydroxyl radical and containing at least one nitrogen atom, the at least one nitrogen atom being substituted with an alkyl chain which is optionally interrupted by an oxygen atom and necessarily containing at least one carboxyl function or at least one hydroxyl function and betainized by reaction with chloroacetic acid or sodium chloroacetate. 
     (9) (C 1 –C 5 )alkyl vinyl ether/maleic anhydride copolymers partially modified by semiamidation with an N,N-dialkylaminoalkylamine such as N,N-dimethylaminopropylamine or by semiesterification with an N,N-dialkanolamine. These copolymers can also contain other vinyl comonomers such as vinylcaprolactam. 
     In some embodiment, the following the cationic or amphoteric polymers may be used: 
     (i) among the cationic polymers:
         the dimethyldiallylammonium chloride homopolymer sold under the name Merquat® 100DRY by the company Merck;   the copolymers of dimethyldiallylammonium chloride and of acrylamide that are sold under the name Merquat® 2200 by the company Calgon;   the polymers of poly(quaternary ammonium) type prepared and described in French patent 2 270 846, which is hereby incorporated by reference, comprise repeating units of formulae (W) and (U) below:       

                         
such as those whose weight-average molar mass, determined by gel permeation chromatography, ranges from 9500 to 9900;
 
                         
such as those whose weight-average molar mass, determined by gel permeation chromatography, is 1200;
         polymers of poly(quaternary ammonium) type of family (11) and of formula (IX) in which X −  is chlorine, such as those whose weight-average molecular mass is less than 100 000, for example less than or equal to 50 000;       
     (ii) among the amphoteric polymers:
         the dimethyldiallylammonium chloride/acrylic acid (80/20) copolymer sold under the name Merquat® 280 Dry by the company Calgon (CTFA name: Polyquaternium 22);   the dimethyldiallylammonium chloride/acrylic acid (95/5) copolymer sold under the name Merquat® 295 Dry by the company Calgon (CTFA name: Polyquaternium 22);   the copolymer of methacrylamidopropyltrimonium chloride, of acrylic acid and of ethyl acrylate, sold under the name Merquat® 2001 by the company Calgon (CTFA name: Polyquaternium 47); and   the acrylamide/dimethyldiallylammonium chloride/acrylic acid terpolymer sold under the name Merquat® Plus 3330 Dry by the company Calgon (CTFA name: Polyquaternium 39).       

     When they are present in the inventive pulverulent compositions, the cationic and/or amphoteric polymers are present in an amount by weight of less than or equal to 20% relative to the total weight of the said composition, such as less than or equal to 8%. 
     Preparation of the Bleaching Powder 
     The bleaching powder of the invention can be prepared by simple addition of the desired amount of polydecene of formula described above to a powdery mixture comprising peroxygenated salt(s), alkaline agents(s), anionic and/or nonionic amphiphilic polymer(s), and optionally a water-soluble thickening polymer and silica. 
     Aqueous Hydrogen Peroxide Composition 
     In one embodiment, the aqueous hydrogen peroxide composition of the invention does not have a titre of more than 40 volumes, and its titre may range from 2 to 40 volumes. 
     The composition is formulated for cosmetic use and may contain at least one ingredient chosen from the following: 
     (i) at least one surfactant chosen from anionic and nonionic surfactants and optionally at least another surfactant chosen from nonionic, anionic, cationic, and zwitterionic surfactants, the surfactant(s) being present in a total amount by weight ranging from 0.1% to 10%, such as from 0.1% to 5% relative to the total weight of the aqueous hydrogen peroxide composition; 
     (ii) a combination of at least two nonionic surfactants with HLB (Hydrophilic Lipophilic Balance) values that are different, and at least one of which is less than or equal to 5 according to the Griffin* scale, in an amount by weight ranging from 1.5% to 40%, for example from 1.5% to 20% relative to the total weight of the aqueous hydrogen peroxide composition; (Griffin* defined in the publication J. Soc. Cosm. Chem. 1954 (Volume 5), pages 249–256, or the HLB value determined experimentally and as described in the book by F. Puisieux and M. Seiller, entitled “Galenica 5: Dispersed systems—Volume I—Surface agents and emulsions—Chapter IV—Notions of HLB and of critical HLB, pages 153–194—paragraph 1.1.2. Determination of HLB experimentally, pages 164–180); 
     (iii) a combination of a nonionic surfactant with an HLB (Hydrophilic Lipophilic Balance) value of less than or equal to 5 according to the Griffin* scale and an anionic surfactant, in a total amount by weight ranging from 1% to 30%, such as from 1.5% to 15%, relative to the total weight of the aqueous hydrogen peroxide composition; and 
     (iv) at least one thickening polymer irrespective of its chemical nature, in an amount by weight ranging from 0.1% to 10%, such as from 0.1% to 5%, relative to the total weight of the aqueous hydrogen peroxide composition; 
     the said polymer optionally being combined with a surfactant of any type, in a weight proportion ranging from 0.1% to 10% and preferably from 0.1% to 5% relative to the total weight of the aqueous hydrogen peroxide composition. 
     This thickening polymer is chosen, for example, from the water-soluble thickening polymers already described above, amphiphilic polymers comprising at least one fatty chain and which may be chosen from nonionic and anionic polymers such as those described above for the non-volatile pulverulent composition, or alternatively from cationic and amphoteric polymers such as those described below. 
     Because the hydrogen peroxide composition is aqueous, the amphiphilic polymers of nonionic or anionic type may also be in the form of water-based solutions or dispersions. 
     Exemplary polymers include fatty-chain nonionic polyurethane polyethers such as: 
     Aculyn® 44 and Aculyn® 46 from the company Rohm &amp; Haas [Aculyn 46 is a polycondensate of polyethylene glycol containing 150 or 180 mol of ethylene oxide, of stearyl alcohol and of methylenebis(4-cyclohexyl isocyanate) (SMDI), at a concentration of 15% by weight in a matrix of maltodextrin (4%) and water (81%); Aculyn 44 is a polycondensate of polyethylene glycol containing 150 or 180 mol of ethylene oxide, of decyl alcohol and of methylenebis(4-cyclohexyl isocyanate) (SMDI), at a concentration of 35% by weight in a mixture of propylene glycol (39%) and water (26%)];
         the product DW 1206B from Rohm &amp; Haas, containing a C 20  alkyl chain and a urethane bond, sold at a solids content of 20% in water;   the products Rheolate® 255, Rheolate® 278 and Rheolate® 244 sold by the company Rheox, or the products DW 1206F and DW 1206J sold by the company Rohm &amp; Haas.       

     Other exemplary polymers include fatty-chain anionic amphiphilic polymers such as, for example:
         crosslinked terpolymers of methacrylic acid, and of ethyl acrylate, of polyethylene glycol (10 EO) stearyl ether (Steareth 10), sold by the company Allied Colloids under the names Salcare® SC 80 and Salcare® SC 90 which are aqueous 30% emulsions of a crosslinked terpolymer of methacrylic acid, of ethyl acrylate and of steareth-10 allyl ether (40/50/10);   the methacrylic acid/methyl acrylate/ethoxylated (40 EO) behenyl dimethyl-meta-isopropenylbenzylisocyanate as an aqueous 25% dispersion, described in Example 3 of patent EP-A-0 173 109, which is hereby incorporated by reference.       

     Among the amphiphilic polymers comprising at least one fatty chain and of amphoteric type, mention may be made of those comprising at least one non-cyclic cationic unit. Such polymers can be prepared from or can comprise from 1 mol % to 20 mol % of monomers comprising a fatty chain, such as from 1.5 mol % to 15 mol %, for example from 1.5 mol % to 6 mol %, relative to the total number of moles of monomers. 
     In one embodiment, amphoteric amphiphilic polymers comprise, or are prepared by copolymerizing: 
     1) at least one monomer of formula (Ia) or (Ib): 
                         
in which
 
     R 1  and R 2 , which may be identical or different, are chosen from a hydrogen atom and a methyl radical, 
     R 3 , R 4  and R 5 , which may be identical or different, are chosen from linear and branched alkyl radicals containing from 1 to 30 carbon atoms, 
     Z is chosen from an NH group and an oxygen atom, 
     n is an integer from 2 to 5, 
     A −  is an anion derived from an organic or mineral acid, such as a methosulphate anion or a halide such as chloride or bromide; 
     2) at least one monomer of formula (II)
 
R 6 —CH═CR 7 —COOH  (II)
 
in which R 6  and R 7 , which may be identical or different, are chosen from a hydrogen atom and a methyl radical; and
 
     3) at least one monomer of formula (III):
 
R 6 —CH═CR 7 —COXR 8   (III)
 
in which
 
     R 6  and R 7 , which may be identical or different, are chosen from a hydrogen atom and a methyl radical, 
     X is chosen from oxygen and nitrogen atoms, and 
     R 8  is chosen from linear and branched alkyl radicals containing from 1 to 30 carbon atoms; 
     at least one of the monomers of formula (Ia), (Ib) or (III) comprising at least one fatty chain. 
     The monomers of formulae (Ia) and (Ib) may, for example, be chosen from:
         dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate,   diethylaminoethyl methacrylate, diethylaminoethyl acrylate,   dimethylaminopropyl methacrylate, dimethylaminopropyl acrylate,   dimethylaminopropylmethacrylamide, dimethylaminopropylacrylamide;       

     these monomers optionally being quaternized, for example, with a C 1 –C 4  alkyl halide or a C 1 –C 4  dialkyl sulphate. 
     In one embodiment, the monomer of formula (Ia) is chosen from acrylamidopropyltrimethylammonium chloride and methacrylamidopropyltrimethylolammonium chloride. 
     In another embodiment, the monomers of formula (II) are chosen from acrylic acid, methacrylic acid, crotonic acid and 2-methylcrotonic acid. In yet another embodiment, the monomer of formula (II) is acrylic acid. 
     In one embodiment, the monomers of formula (III) are chosen from C 12 –C 22 , such as C 16 –C 18  alkyl acrylates and methacrylates. 
     The monomers comprising the fatty-chain amphoteric polymers may be already neutralized and/or quaternized. 
     In one embodiment, the ratio of the number of cationic charges/anionic charges is preferably equal to 1. 
     The amphoteric amphiphilic polymers may, for example comprise from 1 mol % to 10 mol % of the monomer comprising a fatty chain (monomer of formula (Ia), (Ib) or (III)), and as a further example from 1.5 mol % to 6 mol %. 
     The weight-average molecular weights of the amphoteric amphiphilic polymers may range from 500 to 50 000 000, such as from 10 000 to 5 000 000. 
     The amphoteric amphiphilic polymers may also contain other monomers such as nonionic monomers, for example C 1 –C 4  alkyl acrylates or methacrylates. 
     Certain amphoteric amphiphilic polymers are described and prepared, for example, in patent application WO 98/44012, which is hereby incorporated by reference. 
     Among these polymers, the ones that may be used in one embodiment of the invention are acrylic acid/(meth)acrylamidopropyltrimethylammonium chloride/stearyl methacrylate terpolymers. 
     Among the amphiphilic polymers comprising at least one fatty chain and of cationic type, mention may be made, for example: 
     (I)—those chosen from quaternized cellulose derivatives including, for example;
         quaternized celluloses modified with groups comprising at least one fatty chain, such as alkyl, arylalkyl or alkylaryl groups comprising at least 8 carbon atoms, or mixtures thereof;   quaternized hydroxyethylcelluloses modified with groups comprising at least one fatty chain, such as alkyl, arylalkyl or alkylaryl groups comprising at least 8 carbon atoms, or mixtures thereof.       

     The alkyl radicals borne by the above quaternized celluloses or hydroxyethylcelluloses may comprise from 8 to 30 carbon atoms. In one embodiment, the aryl radicals may denote groups chosen from phenyl, benzyl, naphthyl and anthryl groups. 
     Examples of quaternized alkylhydroxyethylcelluloses containing C 8 –C 30  fatty chains which may be mentioned are the products Quatrisoft® LM 200, Quatrisoft® LM-X 529-18-A, Quatrisoft® LM-X 529-18B (C 12  alkyl) and Quatrisoft® LM-X 529-8 (C 18  alkyl) sold by the company Amerchol and the products Crodacel® QM, Crodacel® QL (C 12  alkyl) and Crodacel® QS (C 18  alkyl) sold by the company Croda; 
     (II)—those chosen from quaternized and non-quaternized polyacrylates containing non-cyclic amino side groups, which have, for example, hydrophobic groups of the type such as steareth 20 (polyoxyethylenated (20) stearyl alcohol). 
     As examples of polyacrylates containing amino side chains, mention may be made of the polymers 8781-121B or 9492-103 sold by the company National Starch. 
     (III)—those chosen from the family of cationic associative polyurethanes described by the Applicant in French patent application number 0 009 609, which is hereby incorporated by reference; they may be represented by the general (XIX) below:
 
R—X—(P) n —[L—(Y) m ] r —L′—(P′) p —X′—R′  (XIX)
 
in which:
 
     R and R′, which may be identical or different, are chosen from hydrophobic groups and a hydrogen atom; 
     X and X′, which may be identical or different, are chosen from groups comprising an amine function optionally comprising a hydrophobic group, or alternatively a group L″; 
     L, L′ and L″, which may be identical or different, are chosen from groups derived from diisocyanate; 
     P and P′, which may be identical or different, are chosen from groups comprising an amine function optionally bearing a hydrophobic group; 
     Y is chosen from hydrophilic groups; 
     r is an integer ranging from 1 to 100, for example, ranging from 1 to 50, such as from 1 to 25, 
     n, m and p each, independently of each other, range from 0 to 1000; 
     the molecule containing at least one protonated or quaternized amine function and at least one hydrophobic group. 
     In one embodiment of these polyurethanes, the only hydrophobic groups are the groups R and R′ at the ends of the chain. 
     In another embodiment, one family of cationic associative polyurethanes is the one corresponding to formula (XIX) described above in which: 
     R and R′ both independently are a hydrophobic group, 
     X and X′ each are a group L″, 
     n and p range from 1 to 1000, and 
     L, L′, L″, P, P′, Y and m have the meaning given above. 
     Another useful family of cationic associative polyurethanes is the one corresponding to formula (XIX) above in which: 
     R and R′ both independently are a hydrophobic group, X and X′ each are a group L″, n and p are 0, and L, L′, L″, Y and m have the meaning given above. 
     The fact that n and p are 0 means that these polymers comprise no units derived from a monomer containing an amine function, incorporated into the polymer during the polycondensation. The protonated amine functions of these polyurethanes result from the hydrolysis of excess isocyanate functions at the end of the chain, followed by the alkylation of the primary amine functions formed with alkylating agents containing a hydrophobic group, that is to say compounds of the type RQ or R′Q, in which R and R′ are as defined above and Q denotes a leaving group such as a halide, a sulphate, etc. 
     Yet another useful family of cationic associative polyurethanes is the one corresponding to formula (XIX) above in which: 
     R and R′ both independently are a hydrophobic group, 
     X and X′ both independently are a group comprising a quaternary amine, 
     n and p are 0, and 
     L, L′, Y and m have the meaning given above. 
     The number-average molecular mass of the cationic associative polyurethanes may range from 400 to 500 000, for example, for example, from 1000 to 400 000, such as from 1000 to 300 000. 
     The term “hydrophobic group” means a radical or polymer containing a saturated or unsaturated, linear or branched hydrocarbon-based chain which may contain at least one hetero atom such as P, O, N and S, or a radical containing a perfluoro or silicone chain. When it denotes a hydrocarbon-based radical, the hydrophobic group comprises at least 10 carbon atoms, preferably from 10 to 30 carbon atoms, for example from 12 to 30 carbon atoms and, as a further example, from 18 to 30 carbon atoms. 
     The hydrocarbon-based group can be derived from a monofunctional compound. 
     By way of example, the hydrophobic group may be derived from a fatty alcohol such as stearyl alcohol, dodecyl alcohol or decyl alcohol. It may also denote a hydrocarbon-based polymer such as, for example, polybutadiene. 
     When X and/or X′ denote(s) a group comprising a tertiary or quaternary amine, X and/or X′ may represent one of the following formulae: 
                         
in which:
 
     R 2  is chosen from linear and branched alkylene radicals containing from 1 to 20 carbon atoms, optionally comprising a saturated or unsaturated ring, or an arylene radical, or at least one of the carbon atoms possibly being replaced with a hetero atom chosen from N, S, O and P; 
     R 1  and R 3 , which may be identical or different, are chosen from linear and branched C 1 –C 30  alkyl and linear and branched C 1 –C 30  alkenyl radicals and an aryl radical, at least one of the carbon atoms possibly being replaced with a hetero atom chosen from N, S, O and P; 
     A −  is a physiologically acceptable counterion. 
     The groups L, L′ and L″ may be chosen from a group of formula: 
                         
in which:
 
     Z is chosen from —O—, —S— and —NH—; and 
     R 4  is chosen from linear and branched alkylene radicals containing from 1 to 20 carbon atoms, optionally comprising a saturated or unsaturated ring or an arylene radical, at least one of the carbon atoms possibly being replaced with a hetero atom chosen from N, S, O and P. 
     The groups P and P′ comprising an amine function may be chosen from at least one of the following formulae: 
                         
in which:
 
     R 5  and R 7  have the same meanings as R 2  defined above in paragraph 0274; 
     R 6 , R 8  and R 9  have the same meanings as R 1  and R 3  defined above in paragraph 0275; 
     R 10  is chosen from a linear and branched, optionally unsaturated alkylene groups which may contain at least one hetero atom chosen from N, O, S and P, and 
     A −  is a physiologically acceptable counterion. 
     With respect to the definition of Y, the term “hydrophilic group” means a polymeric or non-polymeric water-soluble group. 
     By way of example, when the hydrophilic group is non-polymeric, exemplary polymers include ethylene glycol, diethylene glycol and propylene glycol. 
     When, in accordance with an embodiment of the invention, the hydrophilic group comprises hydrophilic polymers, exemplary polymers include polyethers, sulphonated polyesters, sulphonated polyamides or a mixture of these polymers. The hydrophilic compound can be a polyether and in particular a poly(ethylene oxide) or poly(propylene oxide). 
     The cationic associative polyurethanes of formula (XIX) according to the invention are formed from diisocyanates and from various compounds with functions containing a labile hydrogen. The functions containing a labile hydrogen may be alcohol, primary or secondary amine or thiol functions giving, after reaction with the diisocyanate functions, respectively, polyurethanes, polyureas and polythioureas. The term “polyurethanes” as used herein encompasses these three types of polymer, namely polyurethanes themselves, polyureas and polythioureas, as well as copolymers thereof. 
     A first type of compound involved in the preparation of the polyurethane of formula (XIX) can comprise at least one unit containing an amine function. This compound may be multifunctional. If the compound is difunctional, i.e., the compound can comprise two labile hydrogen atoms borne, for example, by a hydroxyl, primary amine, secondary amine or thiol function. A mixture of multifunctional and difunctional compounds in which the percentage of multifunctional compounds is low may also be used. 
     As mentioned above, this compound may comprise more than one unit containing an amine function. The compound can be a polymer having a repeat unit comprising an amine function. Compounds of this type may be represented by one of the following formulae:
 
HZ—(P) n —ZH
 
or
 
HZ—(P′) p —ZH
 
in which Z, P, and P′ are as defined above in paragraphs 0278 and 0280, and n and p are as defined above in paragraph 0253.
 
     As examples of compounds containing an amine function, mention may be made of N-methyldiethanolamine, N-tert-butyldiethanolamine and N-sulphoethyldiethanolamine. 
     The second compound involved in the preparation of the polyurethane of formula (XIX) can be a diisocyanate corresponding to the formula:
 
O═C═N—R 4 —N═C═O
 
in which R 4  is defined above in paragraph 0279.
 
     By way of example, mention may be made of methylenediphenyl diisocyanate, methylenecyclohexane diisocyanate, isophorone diisocyanate, toluene diisocyanate, naphthalene diisocyanate, butane diisocyanate and hexane diisocyanate. 
     A third compound involved in the preparation of the polyurethane of formula (XIX) can be a hydrophobic compound intended to form the terminal hydrophobic groups of the polymer of formula (XIX). 
     This compound comprises a hydrophobic group and a function containing a labile hydrogen, for example a hydroxyl, primary or secondary amine or thiol function. 
     By way of example, this compound may be a fatty alcohol such as, in particular, stearyl alcohol, dodecyl alcohol or decyl alcohol. When this compound comprises a polymeric chain, it may be, for example, hydroxylated hydrogenated polybutadiene. 
     The hydrophobic group of the polyurethane of formula (XIX) may also result from the quaternization reaction of the tertiary amine of the compound comprising at least one tertiary amine unit, i.e., the hydrophobic group can be introduced via the quaternizing agent. This quaternizing agent can be a compound of the type RQ or R′Q, in which R and R′ are as defined above in paragraph 0257, and Q denotes a leaving group such as a halide, a sulphate, etc. 
     The cationic associative polyurethane may also comprise a hydrophilic sequence. This sequence is provided by a fourth type of compound involved in the preparation of the polymer. This compound may be multifunctional, and in one embodiment, it is difunctional. It is also possible to have a mixture in which the percentage of multifunctional compound is low. 
     The functions containing a labile hydrogen can be alcohol, primary or secondary amine or thiol functions. This compound may be a polymer terminated at the chain ends with one of these functions containing a labile hydrogen. 
     By way of example, when they are not polymers, mention may be made of ethylene glycol, diethylene glycol and propylene glycol. 
     When they are hydrophilic polymers, mention may be made, for example, of polyethers, sulphonated polyesters and sulphonated polyamides, or a mixture of these polymers. In one embodiment, the hydrophilic compound is a polyether, such as a poly(ethylene oxide) or poly(propylene oxide). 
     The hydrophilic group termed Y in formula (XIX) is optional. Specifically, the units containing a quaternary or protonated amine function may suffice to provide the solubility or water-dispersibility required for this type of polymer in an aqueous solution. Although the presence of a hydrophilic group Y is optional, in one embodiment of the invention, the cationic associative polyurethanes comprise such a group. 
     (IV)—those chosen from cationic polyvinyllactams, the family of which is described in French patent application No 0 101 106, which is hereby incorporated by reference. 
     The polymers are formed from monomers comprising: 
     a) at least one monomer chosen from vinyllactam and alkylvinyllactam monomers; 
     b) at least one monomer of structure (I) or (II) below: 
                         
in which:
 
     X is chosen from an oxygen atom and a radical NR 6 , 
     R 1  and R 6  are chosen, independently of each other, from a hydrogen atom and linear and branched C 1 –C 5  alkyl radicals, 
     R 2  is chosen from linear and branched C 1 –C 4  alkyl radicals, 
     R 3 , R 4  and R 5  are chosen, independently of each other, from a hydrogen atom, linear and branched C 1 –C 30  alkyl radicals and a radicals of formula (III):
 
—(Y 2 ) r —(CH 2 —CH(R 7 )—O) x —R 8   (III)
 
     Y, Y 1  and Y 2  are chosen, independently of each other, from linear and branched C 2 –C 16  alkylene radicals, 
     R 7  is chosen from a hydrogen atom, linear and branched C 1 –C 4  alkyl radicals, and linear and branched C 1 –C 4  hydroxyalkyl radicals, 
     R 8  is chosen from a hydrogen atom, and linear and branched C 1 –C 30  alkyl radicals, 
     p, q and r, independently of each other, are chosen from 0 and 1, 
     m and n, independently of each other, are chosen from integers ranging from 0 to 100, 
     x is chosen from integers ranging from 1 to 100, 
     Z −  is chosen from an organic and mineral acid anions, 
     with the proviso that:
         at least one of the substituents R 3 , R 4 , R 5  or R 8  is chosen from linear and branched C 9 –C 30  alkyl radicals,   if m or n is other than zero, then q is equal to 1,   if m or n are equal to zero, then p or q is equal to 0.       

     The cationic poly(vinyllactam) polymers may be crosslinked or non-crosslinked and may also be block polymers. 
     In one embodiment, the counterion Z −  of the monomers of formula (I) is chosen from halide ions, phosphate ions, the methosulphate ion and the tosylate ion. 
     In one embodiment, R 3 , R 4  and R 5 , independently of each other, are chosen from a hydrogen atom and linear and branched C 1 –C 30  alkyl radicals. 
     In another embodiment, the monomer b) is a monomer of formula (I) for which m and n are equal to 0. 
     The vinyllactam or alkylvinyllactam monomer may be, for example, a compound of structure (IV): 
                         
in which:
 
     s is an integer ranging from 3 to 6, 
     R 9  is chosen from a hydrogen atom and a C 1 –C 5  alkyl radical, 
     R 10  is chosen from a hydrogen atom and a C 1 –C 5  alkyl radical, 
     with the proviso that at least one of the radicals R 9  and R 10  is a hydrogen atom. 
     In one embodiment, the monomer (IV) is vinylpyrrolidone. 
     The cationic poly(vinyllactam) polymers may also contain at least one additional monomer, such as cationic or nonionic monomers. 
     In one embodiment, cationic polyvinyllactams can be one of the following terpolymers comprising at least: 
     a) one monomer of formula (IV), 
     b) one monomer of formula (I) in which p=1, q=0, R 3  and R 4 , independently of each other, are chosen from a hydrogen atom and C 1 –C 5  alkyl radicals, and R 5  is chosen from C 9 –C 24  alkyl radicals, and 
     c) a monomer of formula (II) in which R 3  and R 4 , independently of each other, are chosen from a hydrogen atom and C 1 –C 5  alkyl radicals. 
     The terpolymers can comprise, by weight, 40% to 95% of monomer (a), 0.1% to 55% of monomer (c) and 0.25% to 50% of monomer (b). Such polymers are described in patent application WO 00/68282, which is hereby incorporated by reference. 
     Exemplary cationic poly(vinyllactam) polymers include
     vinylpyrrolidone/dimethylaminopropylmethacrylamide/-dodecyldimethylmethacrylamidopropylammonium tosylate terpolymers,   vinylpyrrolidone/dimethylaminopropylmethacrylamide/cocoyldimethylmethacrylamidopropyl-ammonium tosylate terpolymers,   vinylpyrrolidone/dimethylaminopropylmethacrylamide/lauryldimethyl-methacrylamidopropylammonium tosylate and chloride terpolymers.   

     The weight-average molecular mass of the cationic poly(vinyllactam) polymers may range from 500 to 20 000 000. In other embodiment, the weight-average molecular mass ranges from 200 000 to 2 000 000, such as from 400 000 to 800 000. 
     Oxyalkylenated Nonionic Surfactants with an HLB Value of Less Than or Equal to 5 
     Among these surfactants, mention may be made, in a non-limiting manner, of: 
     oxyethylenated alkylphenols containing not more than 2 mol of EO, 
     EO/PO condensates in which the EO/PO ratio is greater than 0.71, 
     oxyethylenated plant oils containing not more than 5 mol of EO, 
     oxyethylenated fatty alcohols containing not more than 2 mol of EO, 
     fatty alcohols and fatty alcohol esters, for example those containing from 8 to 18 carbon atoms, 
     fatty amides, for example those containing from 8 to 18 carbon atoms. 
     Surfactant(s) of Anionic, Nonionic, Amphoteric, Zwitterionic or Cationic Type: 
     Anionic Surfactants 
     By way of example of anionic surfactants which can be used, alone or as mixtures, mention may be made (nonlimiting list) of salts, such as alkali metal salts, for example those chosen from sodium salts, ammonium salts, amine salts, amino alcohol salts and magnesium salts, of the following compounds: sulphates such as alkyl sulphates, alkyl ether sulphates, alkylamido ether sulphates, alkylarylpolyether sulphates, monoglyceride sulphates; sulphonates such as alkyl sulphonates, alkyl phosphates, alkylamide sulphonates, alkylaryl sulphonates, α-olefin sulphonates, paraffin sulphonates; sulphosuccinates such as (C 6 –C 24 )alkyl sulphosuccinates, (C 6 –C 24 )alkyl ether sulphosuccinates, (C 6 –C 24 )alkylamide sulphosuccinates; (C 6 –C 24 )alkyl sulphoacetates; (C 6 –C 24  )acyl sarcosinates; and (C 6 –C 24 )acyl glutamates. It is also possible to use (C 6 –C 24 )alkylpolyglycoside carboxylic esters such as alkylglucoside citrates, alkylpolyglycoside tartrates and alkylpolyglycoside sulphosuccinates, alkylsulphosuccinamates; acyl isethionates and N-acyl taurates, the alkyl or acyl radical of all of these different compounds containing, e.g., from 12 to 20 carbon atoms and the aryl radical, e.g., denoting a phenyl or benzyl group. Among the anionic surfactants which can also be used, mention may also be made of fatty acid salts such as oleic, ricinoleic, palmitic and stearic acid salts, coconut oil acid or hydrogenated coconut oil acid; acyl lactylates in which the acyl radical contains 8 to 20 carbon atoms. It is also possible to use alkyl D-galactoside uronic acids and their salts, polyoxyalkylenated (C 6 –C 24 )alkyl ether carboxylic acids, polyoxyalkylenated (C 6 –C 24 )alkylaryl ether carboxylic acids, polyoxyalkylenated (C 6 –C 24 )alkylamido ether carboxylic acids and their salts, such as those containing from 2 to 50 alkylene oxide groups such as ethylene oxide groups, and mixtures thereof. 
     Nonionic Surfactant(s): 
     The nonionic surfactants include compounds such as those listed in “Handbook of Surfactants” by M. R. Porter, published by Blackie &amp; Son (Glasgow and London), 1991, pp. 116–178). Thus, they can be chosen from (non-limiting list) polyethoxylated, polypropoxylated, alkylphenols, alpha-diols or alcohols having a fatty chain containing, for example, 8 to 18 carbon atoms, it being possible for the number of ethylene oxide or propylene oxide groups to range from 2 to 50. Mention may also be made of copolymers of ethylene oxide and of propylene oxide, condensates of ethylene oxide and of propylene oxide with fatty alcohols; polyethoxylated fatty amides, such as those having from 2 to 30 mol of ethylene oxide, polyglycerolated fatty amides containing on average 1 to 5, such as 1.5 to 4, glycerol groups; polyethoxylated fatty amines such as those having 2 to 30 mol of ethylene oxide; oxyethylenated fatty acid esters of sorbitan having from 2 to 30 mol of ethylene oxide; fatty acid esters of sucrose, fatty acid esters of polyethylene glycol, alkylpolyglycosides, N-alkylglucamine derivatives, and amine oxides such as (C 10 –C 14 )alkylamine oxides and N-acylaminopropylmorpholine oxides. 
     Amphoteric or Zwitterionic Surfactants: 
     The amphoteric or zwitterionic surfactants, can be chosen from (nonlimiting list), aliphatic secondary and aliphatic tertiary amine derivatives in which the aliphatic radical is a linear or branched chain containing 8 to 18 carbon atoms and containing at least one water-solubilizing anionic group (for example carboxylate, sulphonate, sulphate, phosphate or phosphonate); mention may also be made of (C 8 –C 20 )alkylbetaines, sulphobetaines, (C 8 –C 20 )alkylamido(C 1 –C 6 ) alkylbetaines or (C 8 –C 20 )alkylamido(C 1 –C 6 )alkylsulphobetaines. 
     Among the amine derivatives, mention may be made of the products sold under the name Miranol, as described in U.S. Pat. Nos. 2,528,378 and 2,781,354, the disclosures of which are hereby incorporated by reference, and classified in the CTFA dictionary, 3rd edition, 1982, under the names Amphocarboxyglycinates and Amphocarboxypropionates, with the respective structures:
 
R 2 —CONHCH 2 CH 2 —N(R 3 )(R 4 )(CH 2 COO—)
 
in which:
 
     R 2  is an alkyl radical of an acid R 2 —COOH present in hydrolyzed coconut oil, a heptyl, nonyl or undecyl radical, 
     R 3  is a beta-hydroxyethyl group, 
     R 4  is a carboxymethyl group; and
 
R 2 —CONHCH 2 CH 2 —N(B)(C)
 
in which:
 
     B is —CH 2 CH 2 OX′, 
     C is —(CH 2 ) z —Y′, with z=1 or 2, 
     X′ is chosen from a —CH 2 CH 2 —COOH group and a hydrogen atom, 
     Y′ is chosen from —COOH and a —CH 2 —CHOH—SO 3 H radical, 
     R 2′  denotes an alkyl radical of an acid R 9 —COOH present in coconut oil or in hydrolysed linseed oil, an alkyl radical, such as a C 7 , C 9 , C 11  or C 13  alkyl radical, a C 17  alkyl radical and its iso form, and an unsaturated C 17  radical. 
     These compounds are classified in the CTFA dictionary, 5th edition, 1993, under the names Disodium Cocoamphodiacetate, Disodium Lauroamphodiacetate, Disodium Caprylamphodiacetate, Disodium Capryloamphodiacetate, Disodium Cocoamphodipropionate, Disodium Lauroamphopropionate, Disodium Caprylamphodipropionate, Disodium Caprylamphodipropionate, Lauroamphodipropionic acid and Cocoamphodipropionic acid. 
     By way of example, mention may be made of the cocoamphodiacetate sold under the trade name Miranol C2M concentrate by the company Rhodia Chimie. 
     Cationic Surfactants: 
     Among the cationic surfactants, mention may be made (nonlimiting list) of: salts of optionally polyoxyalkylenated primary, secondary or tertiary fatty amines; quaternary ammonium salts such as tetraalkylammonium, alkylamidoalkyltrialkylammonium, trialkylbenzylammonium, trialkylhydroxyalkylammonium or alkylpyridinium chlorides or bromides; imidazoline derivatives; or amine oxides of cationic nature. 
     The aqueous hydrogen peroxide composition may contain at least one stabilizer chosen, from for example, alkali metal and alkaline-earth metal pyrophosphates, alkali metal and alkaline-earth metal stannates, phenacetin and oxyquinoline acid salts, for instance oxyquinolenic sulphate. More advantageously, use is made of at least one stannate optionally in combination with at least one pyrophosphate. 
     In one embodiment, the aqueous hydrogen peroxide composition preferably has a pH of less than 7. The acidic pH ensures that the hydrogen peroxide is stable in the composition. 
     This pH may be obtained with the aid of acidifying agents such as, for example, hydrochloric acid, acetic acid, ethydronic acid, phosphoric acid, lactic acid or boric acid, and it may be adjusted conventionally by adding either basifying agents such as, for example, aqueous ammonia, monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, 1,3-diaminopropane, an ammonium or alkali metal (bi)carbonate, an organic carbonate such as guanidine carbonate, or alternatively an alkali metal hydroxide, it being possible, of course, for all these compounds to be taken alone or as a mixture. 
     The aqueous hydrogen peroxide composition may also contain preserving agents, colorants, fragrances, antifoams and sequestering agents such as, for example, ethylenediaminetetraacetic acid (EDTA) or Pentasodium Pentetate (CTFA name). 
     These optional additional compound(s) mentioned above are such that the advantageous properties intrinsically associated with the pulverulent bleaching composition or the ready-to-use bleaching composition according to the invention are not, or are not substantially, adversely affected by the envisaged addition(s). 
     The pH of the ready-to-use bleaching composition ranges from 4 to 12. The pH may, for example, range from 7 to 11.5, such as from 8 to 11. 
     In one embodiment, the bleaching method comprises mixing, at the time of application, a pulverulent composition as described previously with an aqueous hydrogen peroxide composition having a titre of not more than 40 volumes to produce a bleaching composition and applying the bleaching composition to the keratin fibers; leaving the bleaching composition on the fibers for an exposure time ranging from 1 to 60 minutes, for example, from about 10 to 45 minutes; rinsing the fibers; and optionally, washing the rinsed fibers with shampoo, rinsing the washed fibers, and drying the rinsed fibers. 
     Another aspect of the present invention comprises a multi-compartment device, or “kit”, for bleaching human keratin fibers, such as hair. The device comprises at least two compartments, one of which contains a pulverulent composition as described above, and the other of which contains an aqueous hydrogen peroxide composition with a titre of not more than 40 volumes. 
     Another aspect of the present invention provides a method for preparing the said pulverulent composition, mixing, at ambient temperature of about 25° C., at least one polydecene of formula C 10n H [(20n)+2]  in which n ranges from 3 to 9 with a mixture comprising at least one peroxygenated salt and at least one polymer chosen from nonionic and anionic amphiphilic polymers. Said at least one polymer comprises at least one fatty chain. The method can further comprise adding alkaline agent and various other adjuvants. 
     Concrete examples illustrating the invention are given below, without, however, having any limiting nature. 
    
    
     EXAMPLE 1 
     The anhydrous, non-volatile pulverulent composition below for bleaching the hair (A) was prepared (amounts expressed in grams): 
                                    Potassium persulphate   48       Sodium persulphate   8       Sodium metasilicate   12       Ammonium chloride   4.5       Magnesium oxide   1       Urea   4       EDTA (sequestering agent)   1       Clay   4.5       Fatty-chain nonionic amphiphilic polymer:   3       Ser-ad FX 1100 sold by the company Servo Delden       Fatty-chain nonionic amphiphilic polymer:   1       Jaguar XC-95/3 sold by the company Rhodia       Water-soluble thickening polymer:   2       Sodium alginate       Anionic surfactant:   3       Sodium cetostearyl sulphate       Calcium stearate   2       Titanium oxide   2       Colorant   0.2       Polydecene: SILKFLO 366 NF sold by the company Amoco   2                    
1. Assessment of the Stability on Storage of a Sample of Composition (A)
 
     The stability on storage over time of a sample of composition A above was assessed, by measuring the content of sodium persulphate and potassium persulphate of the composition, before and after 2 months of storage at 45° C. (T1 and T2, respectively). (These accelerated storage conditions make it possible to predict the stability of the sample under normal storage conditions). 
     The content of sodium persulphate and of potassium persulphate is expressed in meq/g, and was determined by redox potential assay, in acidic medium and in the presence of ferrous sulphate, using a potassium permanganate solution. 
     The loss of sodium persulphate and of potassium persulphate after 2 months at 45° C. (P) was thus determined by means of the following calculation:
 
( P )=100*[( T 1 −T 2)/ T 1]
 
     When this loss (P) is less than 5%, it is considered that the sample will have good stability under normal storage conditions. 
     The stability on storage of sample (A) was thus studied after 2 months at 45° C.; the results were as follows: 
     
       
         
           
               
               
               
               
             
               
                   
                   
               
               
                   
                 T1 
                 T2 
                   
               
               
                   
                 (content before 
                 (content after 
               
               
                   
                 storage for 2 
                 storage for 2 
                 Loss of 
               
               
                   
                 months at 45° C.) 
                 months at 45° C.) 
                 persulphates 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                 Sample (A) 
                 4.16 meq/g 
                 4.12 meq/g 
                 1% 
               
               
                   
               
            
           
         
       
     
     It is concluded therefrom that the pulverulent bleaching composition (A) shows very good stability on storage. 
     2. Measurement of the Particle Size of Composition (A) 
     A particle size measurement was performed on a sample of composition (A) using a Retsch AS 200 Digit granulometer (oscillation height: 1.25 mm/screening time: 5 minutes). 
     
       
         
           
               
               
               
             
               
                   
                   
               
               
                   
                 Diameter of the screens 
                 Particles retained by 
               
               
                   
                 in microns 
                 the corresponding screen, in % 
               
               
                   
                   
               
             
            
               
                   
                 800 microns 
                 3% 
               
               
                   
                 400 microns 
                 32.5%   
               
               
                   
                 200 microns 
                 53.5%   
               
               
                   
                 125 microns 
                 11.5%   
               
               
                   
                  63 microns 
                 2% 
               
               
                   
                  32 microns 
                 0% 
               
               
                   
                 Bottom 
                 0% 
               
               
                   
                   
               
            
           
         
       
     
     Composition (A) contains no fine particles with a diameter of less than 63 microns. 
     3. Mixing before use of Composition (A) with a Stabilized Aqueous Hydrogen Peroxide Composition 
     Two mixtures prepared were compared before use:
         that of composition (A) with a stabilized aqueous 30-volumes (9%) hydrogen peroxide composition (B),   that of the same composition (A) with a stabilized aqueous hydrogen peroxide composition (Ba) not formulated for cosmetic use (110 volumes) in accordance with the invention.       

     Compositions (B) and (Ba) are given below: 
     (Amounts Expressed in Grams %) 
     
       
         
           
               
               
               
             
               
                   
                   
               
               
                   
                 Composition (B) 
                 Composition (Ba) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                 50% hydrogen peroxide 
                 18 (30 vol) 
                 66 (110 vol) 
               
               
                 Nonionic surfactant of HLB = 1: 
                 2.5 
               
               
                 Cetostearyl alcohol 
               
               
                 Nonionic surfactant of HLB = 2: 
                 0.8 
               
               
                 Trideceth-2 carboxamide MEA 
               
               
                 Nonionic surfactant: 
                 0.6 
               
               
                 30 EO oxyethylenated cetostearyl 
               
               
                 alcohol 
               
               
                 Pentasodium pentetate 
                 0.05 
               
               
                 (sequestering agent) 
               
               
                 Tetrasodium pyrophosphate 
                 0.03 
               
               
                 Sodium stannate 
                 0.02 
               
               
                 85% phosphoric acid 
                 0.4 
               
               
                 Water qs 
                 100 
                 100 
               
               
                   
               
            
           
         
       
     
     Mixtures (A)(B) and (A)(Ba) were prepared by mixing 30 g of the non-volatile pulverulent composition (A) with 45 g of the stabilized aqueous hydrogen peroxide composition (B) or (Ba). 
     4. Results: 
     Each mixture (A)(B) and (A)(Ba) was applied to hair to bleach it. 
     The mixture (A)(Ba) was heterogeneous and unstable. It did not allow an easy or sufficiently precise application without running, and spread onto the areas of the hair that were not intended to be bleached. It gave a heterogeneous hair bleaching effect, leaving the hair coarse. 
     The mixture (A)(B) was homogeneous, easy to apply and thick enough to allow a precise application to the areas of the hair that were intended to be bleached. It gave a powerful and homogeneous hair bleaching effect while at the same time leaving the hair much less coarse than with the mixture (A)(Ba). 
     It was also found that composition (A) allowed larger dilutions, with the stabilized aqueous hydrogen peroxide composition (B) than with the aqueous hydrogen peroxide composition (Ba) not formulated for cosmetic use and not in accordance with the invention. 
     EXAMPLE 2 
     1. The pulverulent, anhydrous, non-volatile hair bleaching compositions (C), (D), (E), (F) and (G) below were prepared: 
     (Amounts Expressed in Grams) 
     
       
         
           
               
               
            
               
                   
                   
               
               
                   
                 COMPOSITIONS 
               
            
           
           
               
               
               
               
               
               
            
               
                   
                 (C) 
                 (D) 
                 (E) 
                 (F) 
                 (G) 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Potassium persulphate 
                 35 
                 37.5 
                 39.5 
                 36 
                 20 
               
               
                 Sodium persulphate 
                 10 
                 5 
                 5 
                   
                 20 
               
               
                 20% Magnesium peroxide 
                   
                 2 
                   
                 1.9 
                 4.3 
               
               
                 Sodium disilicate 
                 12 
                 24 
                 25 
                 22 
                 25 
               
               
                 Sodium metasilicate 
                 12 
                 1.3 
                   
                 2 
               
               
                 Ammonium chloride 
                 3 
                 2.5 
                 2.5 
                 2 
                 4 
               
               
                 Magnesium carbonate 
                 5 
                   
                   
                 4 
                 1.5 
               
               
                 Magnesium oxide 
                   
                   
                 0.3 
               
               
                 Urea 
                 3 
                 4 
                 2 
                 3 
               
               
                 EDTA (sequestering agent) 
                 1 
                 0.5 
                 0.5 
                 0.5 
                 1 
               
               
                 Colloidal silica 
                   
                   
                   
                   
                 0.5 
               
               
                 Fumed silica of hydrophilic nature 
                 2.5 
               
               
                 Fumed silica of hydrophobic nature 
                   
                   
                   
                 2.7 
               
               
                 Clay 
                 3 
                 4 
                 4 
                 3 
                 3 
               
               
                 Fatty-chain nonionic amphiphilic 
                 3 
                   
                   
                   
                 2 
               
               
                 polymer: 
               
               
                 Ser-ad FX 1100 from the company 
               
               
                 Servo Delden 
               
               
                 Fatty-chain nonionic amphiphilic 
                 2.8 
                   
                 1 
                   
                 2 
               
               
                 polymer: Jaguar XC-95/3 from the 
               
               
                 company Rhodia 
               
               
                 Fatty-chain anionic amphiphilic 
                   
                 5 
                 4 
                 5 
               
               
                 polymer: Carbopol ETD2020 from 
               
               
                 the company Goodrich 
               
               
                 Fatty-chain anionic amphiphilic 
                   
                   
                   
                   
                 2 
               
               
                 polymer: Carbopol 1382 from the 
               
               
                 company Goodrich 
               
               
                 Water-soluble thickening polymer: 
                 2 
                   
                   
                   
                 1.7 
               
               
                 unmodified nonionic guar gum 
               
               
                 (Guargel D/15 from the company 
               
               
                 Goodrich) 
               
               
                 Water-soluble thickening polymer: 
                   
                 3 
                 3 
                 0.5 
               
               
                 Primogel from the company Avebe 
               
               
                 Sodium lauryl sarcosinate 
                 2 
                   
                   
                   
                 0.5 
               
               
                 Sodium cetostearyl sulphate 
                 1 
                 2 
                 2 
                 2 
                 3 
               
               
                 Magnesium stearate 
                 3 
                 3 
                   
                 2 
               
               
                 Calcium stearate 
                   
                   
                 3 
                   
                 2 
               
               
                 Polyvinylpyrrolidone 
                 2 
                 2.8 
                 3 
                 2 
                 2 
               
               
                 Titanium oxide 
                 2 
                 1 
                 1 
                 1 
                 2 
               
               
                 Colorant 
                   
                 0.2 
                   
                   
                 0.5 
               
               
                 Amphoteric conditioning polymer: 
                 0.2 
                   
                 0.2 
                   
                 0.5 
               
               
                 Polyquaternium-22 
               
               
                 Fragrance 
                   
                 0.2 
                   
                 0.5 
               
               
                 Polydecene: Silkflo 366 NF from the 
                 9.5 
                 2 
                 2 
                 9.9 
                 2.5 
               
               
                 company Amoco 
               
               
                   
               
            
           
         
       
     
     2. The stabilized aqueous hydrogen peroxide compositions (H), (I), (J), (K) and (L) below were also prepared: 
     (Amounts Expressed in Grams) 
     
       
         
           
               
               
            
               
                   
                   
               
               
                   
                 COMPOSITIONS 
               
            
           
           
               
               
               
               
               
               
            
               
                   
                 (H) 
                 (I) 
                 (J) 
                 (K) 
                 (L) 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 50% Hydrogen peroxide 
                 18 
                 24 
                 18 
                 12 
                 18 
               
               
                   
                 (30 vol) 
                 (40 vol) 
                 (30 
                 (20 
                 (30 
               
               
                   
                   
                   
                 vol) 
                 vol) 
                 vol) 
               
               
                 Nonionic surfactant of HLB = 1 
                   
                   
                 2 
                 1 
               
               
                 Cetostearyl alcohol 
               
               
                 Nonionic surfactant of HLB = 1 
                   
                   
                 1 
                 3 
               
               
                 Cetyl alcohol 
               
               
                 Nonionic surfactant of HLB = 5: 
                 1.1 
               
               
                 2 EO oxyethylenated cetyl 
               
               
                 alcohol 
               
               
                 Nonionic surfactant: 30 EO 
                 3 
                   
                 0.5 
                   
                 1 
               
               
                 oxyethylenated cetostearyl 
               
               
                 alcohol 
               
               
                 Nonionic surfactant: 10 EO 
                 2.2 
                   
                 0.7 
               
               
                 oxyethylenated cetyl alcohol 
               
               
                 Anionic surfactant: Sodium 
                   
                   
                   
                 0.5 
               
               
                 cetearyl sulphate 
               
               
                 Anionic surfactant: Sodium 
                   
                   
                   
                 0.2 
               
               
                 lauryl sulphate 
               
               
                 Anionic surfactant: Sodium 
                   
                   
                 0.1 
                 0.3 
                 1 
               
               
                 (C14/C16) olefin sulphonate 
               
               
                 Anionic surfactant: Sodium 
                   
                   
                 0.1 
               
               
                 cocoyl isethionate 
               
               
                 Fatty-chain anionic 
                 2 
               
               
                 amphiphilic polymer: Aculyn 22 
               
               
                 from the company Rohm &amp; 
               
               
                 Haas 
               
               
                 Water-soluble thickening 
                   
                 2 
               
               
                 polymer: Simulgel EG from the 
               
               
                 company SEPPIC 
               
               
                 Water-soluble thickening 
                   
                 3 
               
               
                 polymer: Hostacerin AMPS 
               
               
                 from the company Clariant 
               
               
                 Disodium phosphate 
                   
                   
                 0.08 
                   
                 0.05 
               
               
                 Pentasodium pentetate 
                 0.05 
                   
                   
                 0.06 
               
               
                 (sequestering agent) 
               
               
                 Tetrasodium pyrophosphate 
                 0.03 
                 0.04 
                 0.03 
                 0.04 
                 0.02 
               
               
                 Sodium stannate 
                 0.01 
                 0.02 
                 0.02 
                 / 
                 0.02 
               
               
                 Fragrance 
                   
                   
                 1 
                 0.5 
               
               
                 Antifoam: Simethicone 
                   
                   
                 0.5 
                 0.6 
               
               
                 Ethydronic acid qs pH 
                   
                 3.5 
                   
                 2.5 
               
               
                 85% Phosphoric acid qs pH 
                 3 
                   
                 2.5 
                   
                 2 
               
            
           
           
               
               
            
               
                 Demineralized water 
                 qs 100 
               
               
                   
               
            
           
         
       
     
     3. The ready-to-use bleaching compositions (C)(H), (D)(L), (E)(J), (F)(K) and (G)(I) below were then prepared: 
     −30 g of the pulverulent composition (C)+60 g of the hydrogen peroxide composition (H), 
     −30 g of the pulverulent composition (D)+40 g of the hydrogen peroxide composition (L), 
     −30 g of the pulverulent composition (E)+45 g of the hydrogen peroxide composition (J), 
     −30 g of the pulverulent composition (F)+40 g of the hydrogen peroxide composition (K), 
     −30 g of the pulverulent composition (G)+40 g of the hydrogen peroxide composition (I). 
     The ready-to-use bleaching compositions thus obtained were homogeneous, easy to apply and thick enough to allow a precise application to the areas of the hair that were intended to be bleached. They gave powerful and homogeneous bleaching effects, while at the same time not leaving the hair coarse. 
     For comparative purposes, ready-to-use bleaching compositions (C)(Ba), (D)(Ba), (E)(Ba), (F)(Ba) and (E)(Ba) which were prepared from 30 g of each of the pulverulent compositions (C) or (D) or (E) or (F) or (G) with 30 g of the hydrogen peroxide composition (Ba) described in paragraph 3. of Example 1, were heterogeneous and too unstable. They did not allow an easy and sufficiently precise application without running, and they spread onto the areas of the hair that were not intended to be bleached. They gave heterogeneous hair bleaching effects and left the hair coarse. 
     In addition, it was found that the pulverulent bleaching compositions (C), (D), (E), (F) and (G) were non-volatile and stable on storage. In addition, they allowed much larger dilutions with the stabilized aqueous hydrogen peroxide compositions (H), (I), (J), (K) and (L), than with the aqueous hydrogen peroxide composition (Ba) not formulated for cosmetic use and not in accordance with the invention.