BLEACHING COMPOSITION COMPRISING A NON-VOLATILE
LIQUID BRANCHED ESTER OF A CARBOXKLIC ACID
WITH A SOLIDIFICATION POINT BELOW 4°C
A subject-matter of the present invention is a composition for bleaching keratinous fibres, in particular human keratinous fibres, such as the hair, comprising at least one peroxygenated salt and at least one nonvolatile liquid branched ester of a carboxylic acid with a solidification point below 4°C which is suitably selected.
The bleaching of human keratinous fibres, more particularly of the hair, takes place by oxidation of the pigment "melanin", resulting in the dissolution and removal, partial or complete, of this pigment.
Use is made, in order to bleach the hair, of bleaching powders comprising a peroxygenated reactant, such as ammonium or alkali metal persulphates, perborates and percarbonates, which are combined, at the time of use/ with an aqueous hydrogen peroxide composition.
As peroxygenated salts and hydrogen peroxide are relatively stable in an acidic medium, it is often necessary to activate them at a basic pH in order to obtain appropriate formation of oxygen. It is thus normal to add alkaline compounds, such as urea, alkali metal or alkaline earth metal silicates and phosphates, in particular alkali raetal metasilicates, or agents which are precursors of ammonia, such as ammonium salts, to the bleaching powders.
However, bleaching powders have a tendency to form dust during their handling, transportation and storage thereof.
In point of fact, the products of which they are composed (persulphates, alkaline silicates) are corrosive
and irritating to the eyes, respiratory tract and mucous membranes.
In order to eliminate the problem of volatility of bleaching powders, pastes have been developed which comprise the said pulverulent agents (peroxygenated salts, alkaline agents, thickeners) in an inert liquid organic vehicle. Such compositions are described in particular in Patent Applications DE 38 14 356 and DE 197 23 538.
However, the bleaching pastes based on this technology which are currently marketed have unsatisfactory physicochemical stability and do not make it possible to obtain sufficiently homogeneous and powerful bleaching. In addition, they do not exhibit an attractive appearance.
Recourse has already been had, in order to overcome the lack of stability of bleaching pastes, of combinations of suitably chosen thickening agents, as is described in Patent Applications EP 0 778 020 and EP 1 034 777.
Use has also been made, in order to guarantee even better stability, of waxes which thicken the inert organic liquid. The term "waxes" is understood in particular to mean products having a melting point of greater than 40°C, or esters of fatty acids which are hydrophobic and which comprise a long chain, or substitution products of beeswax.
However, under these conditions, in order to be
dispersed, indeed even dissolved, in the organic
liquid, the wax has to be molten, which implies heating
it during the manufacturing process.
Furthermore, such compositions based on waxes are sensitive to temperature and to thermal impacts, both during their manufacture and their storage. The pastes
then lose their usual qualities.
In order to overcome these disadvantages, the proposal has been made, in Patent Applications FR 2 842 099 and FR 2 842 100, to use the combination of an inert organic liquid and of a pyrogenic silica with a hydro-philic or hydrophobia nature or the combination of a polydecene and of a gelling agent chosen from pyrogenic silicas with a hydrophilic or hydrophobia nature and diblock, triblock, multiblock or radical block copoly-mers composed of segments of styrene monomer type and of segments of thermoplastic monomer or comonomer type.
However, the bleaching pastes currently available commercially still exhibit the disadvantage of being not very resistant to cold. In particular, problems of syneresis, that is to say of exudation of the oily phase, are observed during storage at low temperatures and during transportation in which temperature cycles occur.
The aim of the present invention is to provide a composition for the bleaching of keratinous fibres which makes it possible to solve the problem of volatility of the powders without exhibiting the disadvantages of the known compositions of the prior art, in particular a composition for the bleaching of keratinous fibres which exhibits good resistance to low temperatures, while making it possible to obtain powerful and homogeneous bleaching and while leaving the hair neither greasy nor rough.
This aim is achieved with the present invention, a subject-matter of which is a composition for the bleaching of keratinous fibres comprising at least one peroxygenated salt and at least one non-volatile liquid branched ester of a carboxylic acid, the solidification point of which is below 4°C, chosen from the compounds with the following structure (I) (Formula Removed)
in which Ri and R2 denote, independently of one another, a C1-C30, preferably C2-C2o, hydrocarbon chain optionally interrupted by one or more oxygen atoms and/or by one or more carbonyl groups and optionally substituted by one or more hydroxyl groups, RI being branched.Another subject-matter of the present invention is a method for bleaching keratinous fibres employing the composition in accordance with the invention and also multicompartment devices for the implementation of this method.
Another subject-matter of the present invention is the use of a non-volatile liquid branched ester of a carboxylic acid, the solidification point of which is below 4°C, as defined above, in a composition for the bleaching of keratinous fibres comprising a peroxy-genated salt.
The present invention makes it possible to obtain a composition for the bleaching of keratinous fibres which exhibits an improved resistance to low temperatures and in particular which makes it possible to avoid the problem of syneresis during storage at low temperatures and during transportation in which temperature cycles occur.
Unless otherwise indicated, the limits of the ranges of values which are given in the context of the present invention are included within these ranges.
The peroxygenated salt or salts present in the composition in accordance with the invention can, for example, be chosen from persulphates, perborates, percarbonates or peroxides of alkali metals or alkaline earth metals, and their mixtures. Preferably, use will

be made of persulphates and their mixtures and more preferably sodium persulphate, potassium persulphate, ammonium persulphate and their mixtures.
The concentration of peroxygenated salts in the composition according to the invention is generally between 10 and 70% by weight and preferably between 20 and 60% by weight of the total weight of the composition.
The term "low temperature" is understood to mean, within the meaning of the present invention, a temperature below 10°C and preferably below 5°C.
The term "liquid" is understood to mean, within the meaning of the present invention, any phase capable of flowing at ambient temperature, generally between 15°C and 40°C, and at atmospheric pressure under the action
of its own weight.
The term "non-volatile" is understood to mean, within the meaning of the present invention, a compound exhibiting a vapour pressure of less than or equal to 5 mmHg at a temperature of 20°C. Preferably, this vapour pressure is less than 1 mmHg.
The term "branched ester" is understood to mean, within the meaning of the present invention, an ester comprising, in the part resulting from an acid and/or in the part resulting from an alcohol, at least one branched hydrocarbon chain comprising at least three carbon atoms.
The non-volatile liquid branched ester or esters of carboxylic acid3 of use in the context of the invention have a solidification temperature below 4°C. This solidification temperature may in particular be determined by DSC (differential scanning calorimetry). Mention may be made, as DSC device which can be used, of the Pyris 1 device from Perkin-Elmer.
The non-volatile liquid branched ester or esters of carboxylic acids having a solidification point below 4°C result from a branched acid.
According to a specific embodiment of the invention, the non-volatile liquid branched ester or esters of carboxylic acids having a solidification point below 4°C comprise at least 8 carbon atoms.
Mention may in particular be made, as esters which can be used in the present invention, of octyl iso-nonanoate, isononyl isononanoate, isobutyl isobutyrate or 2,2,4-trimethyl-l,3-pentanediol butyrate.
Preferably, R1, and R2 are branched. The non-volatile liquid branched ester or esters of carboxylic acids having a solidification point below 4°C then result from a branched acid and from a branched alcohol.
More preferably still, isononyl isononanoate will be used.
The concentration of non-volatile liquid branched
esters of carboxylic acids having a solidification
point below 4°C in the composition according to the
invention is generally between 1 and 70% by weight,
preferably between 5 and 60% by weight and more
preferably still between 10 and 50% by weight of the
total weight of the composition.
According to a specific embodiment, the composition in accordance with the present invention comprises at least one alkaline agent.
The alkaline agent or agents can, for example, be chosen from urea, ammonium salts, such as ammonium chloride, ammonium sulphate, ammonium phosphate or ammonium nitrate, silicates, phosphates or carbonates
of alkali metals or alkaline earth metals, such as lithium, sodium, potassium, magnesium, calcium or barium, and their mixtures. Preferably, the alkaline agent or agents are chosen from silicates, carbonates, ammonium chloride and their mixtures.
When they are present in the composition in accordance with the invention, the concentration of alkaline agents is generally between 0.01 and 40% by weight and preferably between 0.1 and 30% by weight of the total weight of the composition.
According to a specific embodiment, the composition in accordance with the invention comprises at least one additional inert organic liquid other than non-volatile liquid branched esters of carboxylic acids having a solidification temperature below 4°C.
The term "inert organic liquid" is understood to mean, within the meaning of the present invention, an organic liquid which is chemically inert with regard to hydrogen peroxide. In the context of the invention, a liquid is inert if the decomposition of hydrogen peroxide in the presence of this liquid is less than 25% after 15 hours at 100'C.
Mention may be made, by way of example, of polydecenes of formula C1onH((20n)+2] in which n varies from 3 to 9 and preferably from 3 to 7, esters of fatty alcohols or of fatty acids other than the esters of the invention, esters or diesters of sugars and of C12-C24 fatty acids, cyclic ethers or cyclic esters, silicone oils, mineral oils or vegetable oils, or their mixtures.
The compounds of formula C1onH1[(20n)+2) with n varying from 3 to 9 correspond to the term "polydecene" of the CTFA Dictionary, 7th edition, 1997, of the Cosmetic, Toiletry and Fragrance Association, USA, and to the same INCI term in the USA and Europe. These are
polysaccharides.
Mention may be made, as sugars which can be used according to the invention, for example, of sucrose, glucose, galactoae, tibose, fuctose, maltose, fructose, mannose, arabinose, xylose, lactose and their derivatives, in particular alkylated derivatives, such as methylated derivatives, for example methylglucose.
The esters of sugars and of fatty acids which can be used according to the invention can be chosen in particular from the group consisting of the esters or mixtures of esters of sugars described above and of Cn-Cza fatty acids which are saturated or unsaturated and linear or branched.
The esters can be chosen from mono-, di-, tri- and tetraesters, polyesters and their mixtures.
These esters can, for example, be chosen from oleates, laurates, palmitates, myristates, behenates, cocoates, stearates, linoleates, linolenates, caprates, arachi-donates or their mixtures, such as in particular, oleopalmitate, oleostearate or palmitostearate mixed esters.
More particularly, preference is given to the use of mono- and diesters, in particular mono- or dioleates, -stearates, -behenates, -oleopalmitates, -linoleates, -linolenates or -oleostearates, of sucrose, of glucose
or of methylglucose.
Silicone oils can also be employed as inert organic
liquid.
More particularly, suitable silicone oils are liquid and non-volatile silicone fluids with a viscosity of less than or equal to 10 000 mPa•s at 25°C, the viscosity of the silicones being measured according to

Standard ASTM 445 Appendix C.
Silicons oils are defined in more detail in the work by Walter Noll, "Chemistry and Technology of Silicones", 1968, Academic Press.
Mention may in particular be made, among silicone oils which can be used according to the invention, of the silicone oils sold under the names DC 200 Fluid -5 mPa'S, DC 200 Fluid - 20 mPa-s, DC 200 Fluid - 350 mPa-s, DC 200 Fluid - 1000 mPa-s and DC 200 Fluid -10 000 mPa-s by Dow Corning.
Mineral oils can also be used as inert organic liquid, such as, for example, liquid paraffin.
Vegetable oils may also be suitable, in particular avocado oil, olive oil or jojoba liquid wax.
Preferably, the additional inert organic liquid or liquids are chosen from the group formed by polydecenes of formula C1onH(2on)+2) in which n varies from 3 to 9 and preferably from 3 to 7, esters of fatty alcohols or of fatty acids other than the esters of the invention, and their mixtures.
The content of additional inert organic liquids can vary between 5 and 60% by weight, preferably between 10 and 50% by weight and more preferably still between 15 and 45% by weight of the total weight of the composition.
According to a specific embodiment, the composition in accordance with the invention is provided in the form of an anhydrous paste.
In the context of the present invention, a composition is anhydrous when it exhibits a water content of less than 1% by weight and preferably of less than 0.5% by
weight, with respect to the total weight of the
composition,
According to another specific embodiment, the composi-tion in accordance with the invention furthermore comprises hydrogen peroxide.
In that case, the composition according to the invention is ready for use and results from the mixing of a composition provided in the form of an anhydrous paste in accordance with the invention with an aqueous composition comprising hydrogen peroxide. Its pH is generally between the values 3 and 11. It is preferably between 7 and 11.
The composition in accordance with the present invention can also comprise various additives conventionally used
in cosmetics.
The composition in accordance with the present invention can thus comprise inorganic or organic thickening agents, in particular anionic, cationic, nonionic or amphoteric, associative or nonassociative, thickening polymers, fillers, such as clays, binders, such as vinylpyrrolidone, lubricating agents, such as polyol stearates or alkali metal or alkaline earth metal stearates, hydrophilic or hydrophobia silicas, pigments, dyes, mattifying agents, such as titanium oxides, or also anionic, nonionic, cationic, amphoteric or zwitterionic surface-active agents, antioxidizing agents, penetrating agents, sequestering agents, buffers, dispersing agents, film-forming agents, preservatives, opacifying agents, vitamins, fragrances, anionic, cationic, nonionic, amphoteric or zwitterionic polymers, ceramides or conditioning agents, such as, for example, volatile or non-volatile and modified or unmodified silicones.
In the case where the composition in accordance with
the invention comprises hydrogen peroxide, it can also comprise agents for controlling the release of oxygen, such as magnesium carbonate or magnesium oxide.
The additives and agents for controlling the release of oxygen as defined above can be present in an amount of, for each of them, between 0.01 and 40* by weight, preferably between 0.1 and 30% by weight, with respect to the total weight of the composition.
Of course, a person skilled in the art will take care to choose this or these optional additional compounds so that the advantageous properties intrinsically attached to the composition in accordance with the invention are not, or not substantially, detrimentally affected by the envisaged addition or additions.
The bleaching process in accordance with the present invention consists in applying, to the keratinous fibres, a composition provided in the form of an anhydrous paste in accordance with the invention as defined above in the presence of an aqueous composition comprising hydrogen peroxide.
The aqueous composition comprising hydrogen peroxide can be added to the composition provided in the form of an anhydrous paste at the very moment of use. It can also be applied simultaneously with or sequentially to the composition provided in the form of an anhydrous paste.
Another subject-matter of the present invention is a multicompartment device comprising at least two compositions packaged separately, the mixing of which results in a composition comprising hydrogen peroxide in accordance with the invention as defined above.
According to a specific embodiment, the device in accordance with the invention comprises a first
compartment which comprises a composition in the form of an anhydrous paste in accordance with the present invention as defined above and a second compartment which comprises an aqueous composition comprising hydrogen peroxide.
The appropriate cosmetic medium of the aqueous composition comprising hydrogen peroxide is generally composed of water or of a mixture of water and of at least one organic solvent in order to resolve the compounds which would be insufficiently soluble in the water. Mention may be made, as organic solvent, for example, of lower C1-C4 alkanols, such as ethanol and isopropanol; glycerol; glycols and glycol ethers, such as 2-butoxyethanol, propylene glycol or propylene glycol monomethyl ether, and also aromatic alcohols, such as benzyl alcohol or phenoxyethanol, the analogous products and their mixtures.
The solvents can be present in proportions preferably of between 1 and 40% by weight, with respect to the total weight of the dyeing composition, and more preferably still between 5 and 30% by weight approximately.
The aqueous composition comprising hydrogen peroxide preferably exhibits a pH of less than 7, the acidic pH guaranteeing the stability of the hydrogen peroxide in this composition.
The aqueous composition comprising hydrogen peroxide can be provided in various forms, such as in the form of liquids, of creams, of gels or in any other form appropriate for carrying out bleaching of keratinous fibres.
The aqueous composition comprising hydrogen peroxide can also include various additives conventionally used in cosmetics, such as those which are described above.
The aqueous composition comprising hydrogen peroxide can furthermore comprise agents for controlling the release of oxygen as defined above.
The device in accordance with the present invention can be equipped with a means which makes it possible to deliver the desired mixture to the hair, such as the devices described in Patent FR 2 586 913 on behalf of the Applicant Company.
it is possible, starting from this device, to bleach keratinous fibres starting from a process in accordance with the invention as defined above.
Another subject-matter of the present invention is the use of at least one non-volatile liquid branched ester of a carboxylic acid having a solidification point below 4°C as defined above in a composition for the bleaching of keratinous fibres comprising at least one peroxygenated salt.
According to a specific embodiment, the use in accordance with the invention makes it possible to improve the resistance to low temperatures of the composition for the bleaching of keratinous fibres and in particular makes it possible to avoid the problem of syneresis during storage at low temperatures and during transportation in which temperature cycles occur,
The invention will be more fully illustrated using the following non-liraiting examples.
EXAMPLES
The following anhydrous bleaching pastes were prepared:

(Table Removed)Each of the bleaching pastes described above was subjected to various tests in order to evaluate its resistance to cold and to transportation,
Test 1
Each of the bleaching pastes described above was placed in a refrigerator at 4°C for one week. After returning to ambient temperature, the following points were observed:
composition A does not exhibit any modification; in the case of composition B, the hardening of the paste and then the formation of pockets of Oil are
observed. Test 2
Each of the bleaching pastes described above was subjected to two temperature cycles from 20°C to -20'c (one cycle = 6 hours at 20°C, then from 20°C to -20°C in 6 hours, then 6 hours at -20°C, then from -20°C to 20°C in 6 hours), followed by stirring for 1 hour, which simulates the vibrations undergone by a sample during transportation by lorry over a distance of 1000 km. The following points were observed:
composition A does not exhibit any modification; in the case of composition B, phase separation of oil at the surface of the paste is observed,
Test 3
The thermal behaviour during cooling from 25°C to -40°C at a rate of 5°C/minute was recorded by differential scanning calorimetry for each of the bleaching pastes described above. The following points were observed:
composition A does not show any transition; composition B exhibits a pronounced crystallization peak beginning at -4°C.
In conclusion, a clear superiority for resistance to cold and to transportation of the anhydrous paste comprising isononyl isononanoate in comparison with the anhydrous paste comprising isopropyl myristate was observed.
The bleaching composition of the present invention is a synergistic composition showing surprising properties such as good resistance to low temperature powerful and homogeneous bleaching while leaving the hair neither nor rough.

1. Composition for the bleaching of keratinous fibres
comprising at least one peroxygenated salt and at least
one non-volatile liquid branched ester of a carboxylic
acid, the solidification point of which is below 4°C,
chosen from the compounds of following formula (I) (Formula Removed)
in which R1 and R2 denote, independently of one another, a C1-C30, hydrocarbon chain optionally interrupted by one or more oxygen atoms and/or by one or more carbonyl groups and optionally substituted by one or more hydroxyl groups, R1 being branched.
2. Composition according to Claim 1, in which the
peroxygenated salt or salts are chosen from
persulphates, perborates, percarbonates or peroxides of
alkali metals or alkaline earth metals, and their
mixtures .
3. Composition according to Claim 2, in which the
peroxygenated salt or salts are chosen from
persulphates and their mixtures.
4. Composition according to any one of the preceding
claims, in which the concentration of peroxygenated
salts is between 10 and 70% by weight of the total
weight of the composition.
5. Composition according to any one of the preceding
claims, in which the non-volatile liquid branched ester
or esters of carboxylic acids having a solidification
point below 4°C comprise at least 8 carbon atoms.
6. Composition according to any one of the preceding
claims, in which R1 and R2 are branched.
7. Composition according to any one of the preceding
claims, in which the non-volatile liquid branched ester
of a carboxylic acid having a solidification point
below 4°C is isononyl isononanoate.
8. Composition according to any one of the preceding
claims, in which the concentration of non-volatile
liquid branched esters of carboxylic acids having a
solidification point below 4°C is between 1 and 70% by
weight of the total weight of the composition.
9. Composition according to any one of the preceding
claims, comprising at least one alkaline agent.
10. Composition according to Claim 9, in which the
alkaline agent or agents are chosen from urea, ammonium
salts, silicates, phosphates or carbonates of alkali
metals or alkaline earth metals, and their mixtures.
11. Composition according to Claim 10, in which the
alkaline agent or agents are chosen from silicates,
carbonates, ammonium chloride and their mixtures.
12. Composition according to any one of Claims 9 to
11, in which the alkaline agent or agents are in an
amount of between 0.01 and 40% by weight of the total
weight of the composition.
13. Composition according to any one of the preceding
claims, comprising at least one additional inert
organic liquid other than non-volatile liquid branched
esters of carboxylic acids having a solidification
point below 4'C as defined in any one of Claims 1 and 5
to 7.
14. Composition according to Claim 13, in which the
additional inert organic liquid or liquids are chosen
from polydecenes of formula C10nH[(2on)+2) in which n
varies from 3 to 9, esters of fatty alcohols or of
fatty acids other than non-volatile liquid branched esters of carboxylic acids having a solidification point below 4°C as defined in any one of Claims 1 and 5 to 1, eaters or diesters of sugars and of C12-C24 fatty acids, cyclic ethers or cyclic esters, silicone oils, mineral oils or vegetable oils, or their mixtures.
15. Composition according to Claim 13 or 14, in which
the content of additional inert organic liquids varies
between 5 and 60% by weight of the total weight of the
composition.
16. Composition according to any one of the preceding
claims provided in the form of an anhydrous paste.
11. Composition according to any one of Claims 1 to 16 comprising hydrogen peroxide.
18. Bleaching process, consisting in applying, to
keratinous fibres, a composition provided in the form
of an anhydrous paste as defined in Claim 16 in the
presence of an aqueous composition comprising hydrogen
peroxide.
19. Multicompartment device comprising at least two
compositions packaged separately, the mixing of which
results in a composition comprising hydrogen peroxide
as defined in Claim 17.
20. Device according to Claim 19, comprising a first
compartment which comprises a composition in the form
of an anhydrous paste as defined in Claim 16 and a
second compartment which comprises an aqueous
composition comprising hydrogen peroxide.
21. Use of at least one non-volatile liquid branched
ester of a carboxylic acid having a solidification
point below 4°C as defined in any one of Claims 1 and 5
to 7 in a composition for the bleaching of keratinous
fibres comprising at least one peroxygenated salt.
22. Use according to Claim 21 for improving the resistance to low temperatures of the composition for the bleaching of keratinous fibres.
23. A bleaching composition substantially as herein described with reference to the foregoing examples.