EP4658375A1

EP4658375A1 - At least two-part lightening agent comprising a silicate in a particular content, a peroxygenated salt, a compound of amino acid type, a (poly)carboxylic acid and an oxidizing agent

Info

Publication number: EP4658375A1
Application number: EP24702948.1A
Authority: EP
Inventors: Sanàa RAHAL; Hugo DORIE; Virginie SOULIE
Original assignee: LOreal SA
Current assignee: LOreal SA
Priority date: 2023-01-31
Filing date: 2024-01-30
Publication date: 2025-12-10
Also published as: CN120693140A; WO2024160821A1; FR3145274A1

Abstract

The invention relates to a lightening agent comprising a first composition A comprising one or more peroxygenated salts, one or more silicates in a total content of greater than or equal to 25% by weight relative to the weight of the first composition, one or more compound(s) of amino acid type; one or more (poly)carboxylic acids and/or salts thereof, other than the compound(s) of amino acid type; and a second composition B comprising one or more chemical oxidizing agent(s) other than peroxygenated salts. The invention also relates to a process for lightening keratin fibres, preferably human keratin fibres, in particular the hair, comprising the application, to said keratin fibres, of the composition resulting from mixing the first composition with the second composition.

Description

At least two-part lightening agent comprising a silicate in a particular content, a peroxygenated salt, a compound of amino acid type, a (poly)carboxylic acid and an oxidizing agent

The present invention relates to an agent for lightening keratin fibres, and in particular human keratin fibres such as the hair, comprising a first composition A comprising one or more silicates in a particular content, one or more peroxygenated salts, one or more compound(s) of amino acid type and one or more (poly)carboxylic acids other than the compound(s) of amino acid type, and a second composition B comprising a chemical oxidizing agent.
The invention also relates to a process for cosmetic treatment of human keratin fibres using such an agent.
In the field of hair lightening, tone depth is generally used to characterize the degree or level of lightening. The concept of “tone” is based on the classification of natural shades, with one tone separating each shade from the shade immediately following or preceding it. This definition and the classification of natural shades are well known to hairstyling professionals and are published in the book Sciences des traitements capillaires [The Science of Hair Care] by Charles Zviak, 1988, published by Masson, pages 215 and 278.
The tone depths range from 1 (black) to 10 (lightest blond), with one unit corresponding to one tone; the higher the number, the lighter the shade.
Lightening thus makes it possible to provide a lighter tone depth than the initial natural tone depth of the head of hair.
The processes used to lighten the hair generally consist in using an aqueous composition comprising at least one oxidizing agent, under alkaline pH conditions in the vast majority of cases.
The role of this oxidizing agent is to degrade the melanin of the hair, which, depending on the nature of the oxidizing agent present, leads to more or less pronounced lightening of the fibres. Thus, for relatively mild lightening, the oxidizing agent is generally hydrogen peroxide. When more pronounced lightening is desired, particularly lightening by at least 5 tones, use is usually made of peroxygenated salts, for instance persulfates, in the presence of hydrogen peroxide. These peroxygenated salts are contained in compositions which, at the time of use, are mixed with an aqueous composition comprising hydrogen peroxide.
In order to adjust the pH of the compositions to an alkaline pH to enable activation of the oxidizing agent, use is made of an alkaline agent. This alkaline agent also causes swelling of the keratin fibre, with opening of the scales, which promotes the penetration of the oxidizing agent into the fibre, and thus increases the efficacy of the reaction.
However, the use of alkaline agents and peroxygenated salts is not without consequence and may have an adverse effect on the quality of the hair. The essential causes of this adverse effect on the quality of the hair are a decrease in its cosmetic properties, such as its sheen, and degradation of its mechanical properties, more particularly degradation of its mechanical strength, which may also be reflected by an increase in its porosity. The hair is weakened and may become brittle during subsequent treatments such as blow-drying.
Patent application FR3115204 has already proposed hair lightening compositions which reduce damage done to hair fibres during bleaching and which comprise polycarboxylic acid, amino acid and antioxidant. However, it is still possible to improve such compositions.
Thus, one of the objectives of the present invention is to propose agents for lightening human keratin fibres such as hair which do not have the disadvantages mentioned above, that is to say which are capable of leading to very good lightening performance, good cosmetic properties, while preserving as much as possible the mechanical properties of the hair and at the same time offering very good usage qualities.
This and other aims are achieved by the present invention, a subject of which is therefore an agent for lightening keratin fibres which comprises:
a) a first composition A comprising:
- one or more peroxygenated salts,
- one or more silicates in a total content of greater than or equal to 25% by weight relative to the total weight of the first composition A,
- one or more compound(s) of amino acid type,
- one or more (poly)carboxylic acids and/or salts thereof, other than the compound(s) of amino acid type;
b) a second composition B comprising one or more chemical oxidizing agent(s) other than the peroxygenated salts.
According to a preferred embodiment, the agent according to the invention is an agent for lightening human keratin fibres, preferably the hair.
The invention also relates to a lightening process using said lightening agent and to the use of the agent for lightening keratin fibres, and in particular hair.
The lightening agent according to the invention results in high level of lightening, of up to 9 tones, while protecting the hair fibre so as to maintain good integrity of the hair, and while offering good usage qualities.
Other subjects, features, aspects and advantages of the invention will become even more apparent on reading the description and the examples that follow.
In that which will follow, and unless otherwise indicated, the limits of a range of values are included in this range, in particular in the expressions “of between” and “ranging from ... to ...”.
Moreover, the expression “at least one” used in the present description is equivalent to the expression “one or more”.
The lightening agent according to the invention comprises a first composition A and a second composition B.

First composition A

Peroxygenated salts

The first composition A of the lightening agent comprises one or more peroxygenated salts.
Preferably, the peroxygenated salts are chosen from persulfates; perborates; peracids and/or salts thereof; alkali metal, alkaline-earth metal or ammonium percarbonates; magnesium peroxide; and mixtures thereof.
More preferably, the first composition A of the lightening agent according to the present invention comprises at least one persulfate.
Persulfates, also known as peroxysulfates, correspond, for the purposes of the invention, to SO₅ ^2- anions (peroxomonosulfate anion) or S₂O₈ ^2- anions (peroxodisulfate anion) or to compounds comprising at least one of these anions.
Preferably, the persulfates according to the invention are chosen from peroxodisulfates.
According to a preferred embodiment of the invention, the first composition A comprises at least one peroxygenated salt chosen from persulfates; preferably from alkali metal persulfates, alkaline-earth metal persulfates, ammonium persulfates, and mixtures thereof; more preferentially from (bis)tetrabutylammonium persulfate, barium persulfate, magnesium persulfate, calcium persulfate, sodium persulfate, potassium persulfate, ammonium persulfate, and mixtures thereof; even more preferentially from sodium persulfate, potassium persulfate, ammonium persulfate, and mixtures thereof.
Preferably, the total content of peroxygenated salt(s) present in the first composition A of the lightening agent according to the invention ranges from 1 to 80% by weight, preferably from 10 to 70% by weight, more preferentially from 20 to 65% by weight, better still from 30 to 60% by weight relative to the total weight of the first composition A.
Preferably, the total content of persulfate(s) present in the first composition of the lightening agent according to the invention ranges from 1 to 80% by weight, preferably from 10 to 70% by weight, more preferentially from 20 to 65% by weight, better still from 30 to 60% by weight relative to the total weight of the first composition A.

Silicates

The first composition A of the lightening agent according to the invention also comprises one or more silicates.
The term “silicate” means a silicic acid salt.
The silicate(s) are preferably water-soluble.
The term “water-soluble silicate” means a silicate which has a solubility in water at ordinary ambient temperature (25°C) and at atmospheric pressure (760 mmHg) of greater than 0.5% by weight, preferably greater than 1% by weight.
Preferably, the silicate(s) are chosen from alkali metal silicates, alkaline-earth metal silicates, aluminium silicates, trimethylammonium silicates and mixtures thereof.
More preferentially, the silicate(s) are chosen from sodium silicates, potassium silicates, calcium silicates, aluminium silicates, trimethylammonium silicates and mixtures thereof.
The silicate(s) may be chosen from metasilicates, preferably from sodium metasilicates, potassium metasilicates, calcium metasilicates, aluminium metasilicates, trimethylammonium metasilicates, and mixtures thereof.
Even more preferentially, the silicate(s) are chosen from sodium silicates.
Preferably, the silicate(s) are chosen from the compounds having the INCl name Sodium Silicate and/or Sodium Metasilicate.
The silicate(s) are present in the first composition A of the lightening agent according to the invention, preferably in a total content ranging from 25 to 50% by weight, more preferentially from 27 to 40% by weight, better still from 29 to 35% by weight, relative to the total weight of the first composition A.
Advantageously, the sodium silicate(s) are present in the first composition A of the lightening agent according to the invention, preferably in a total content ranging from 25 to 50% by weight, more preferentially from 27 to 40% by weight, better still from 29 to 35% by weight, relative to the total weight of the first composition A.

Compound(s) of amino acid type

The first composition A of the lightening agent according to the invention comprises one or more compound(s) of amino acid type.
For the purposes of the present invention, “compound of amino acid type” means an organic compound comprising one or more carboxylic acid and/or sulfonic acid functions and one or more amine functions, it being possible for the amine function(s) to be endocyclic, optionally in salt form.
Preferably, the compound(s) of amino acid type are chosen from compounds of amino acid type comprising only one or more carboxylic acid functions (thus not comprising any sulfonic acid functions) and/or salts thereof. Said compounds are also called compounds of aminocarboxylic acid type and are particularly preferred.
Preferably, the first composition A of the lightening agent according to the present invention comprises one or more compounds of amino acid type chosen from the compounds corresponding to formula (I) below and/or salts thereof.
The compounds of amino acid type may thus correspond to formula (I):
(I)
in which p is an integer equal to 1 or 2, it being understood that:
when p = 1, R forms, with the nitrogen atom, a saturated heterocycle comprising from 5 to 8 ring members, preferably 5 ring members, it being possible for this ring to be optionally substituted with one or more groups chosen from hydroxyl or (C₁-C₄)alkyl;
- when p = 2, R represents a hydrogen atom or a saturated, linear or branched, (C₁-C₁₂)alkyl, preferably (C₁-C₄)alkyl, group, optionally interrupted with one or more heteroatoms or groups chosen from –S–, –NH– or –C(NH)– and/or optionally substituted with one or more groups chosen from hydroxyl (-OH), amino (-NH₂), -SH, -COOH, -CONH₂ or –NH–C(NH)–NH₂;
Preferably, when p = 1, R forms, with the nitrogen atom, a saturated heterocycle comprising 5 ring members, this ring not being substituted.
Preferably, p = 2.
Preferably, when p = 2, R represents a hydrogen atom or a saturated, linear or branched, (C₁-C₄)alkyl group, optionally interrupted with a –S– heteroatom and/or optionally substituted with one or two groups chosen from hydroxyl, amino or –NH–C(NH)–NH₂.
Preferentially, p = 2 and R represents a hydrogen atom.
The compounds of amino acid type may also be a salt of a compound of formula (I).
These salts comprise salts with organic or mineral bases, for example the salts of alkali metals, for instance lithium, sodium or potassium salts; the salts of alkaline-earth metals, for instance magnesium or calcium salts, and zinc salts.
The compounds of amino acid type may be in the form of an optical isomer of L, D or DL configuration, preferably of L configuration.
As examples according to the present invention of compounds in the form of an optical isomer of L configuration, mention may be made of L-proline, L-methionine, L-serine, L-arginine and L-lysine.
Preferably, the compound(s) of amino acid type according to the invention are chosen from glycine, proline, methionine, serine, arginine, lysine, salts thereof (particularly alkali metal, alkaline-earth metal or zinc salts) and mixtures thereof.
Preferably, the compound(s) of amino acid type according to the invention are chosen from glycine, proline, methionine, serine, arginine, salts thereof and mixtures thereof.
Better still, the compound of amino acid type is chosen from glycine, salts thereof (particularly alkali metal, alkaline-earth metal or zinc salts) and mixtures thereof.
As glycine salts according to the present invention, mention may be made of sodium glycinate, zinc glycinate, calcium glycinate, magnesium glycinate, manganese glycinate and potassium glycinate, preferably sodium glycinate and potassium glycinate.
Preferably, the compound of amino acid type is glycine.
The total content of compound(s) of amino acid type present in the first composition A of the lightening agent according to the invention may range from 0.01% to 5% by weight, preferably from 0,05% to 4% by weight, more preferably from 0,1% to 3% by weight, better still from 0.2 to 2% by weight, even better still from 0.5 to 1.5% by weight relative to the total weight of the first composition A.
In particular, the total content of compound(s) of aminocarboxylic acid type in the first composition A of the lightening agent according to the invention may range from 0.01% to 5% by weight, preferably from 0.05% to 4% by weight, more preferably from 0.1% to 3% by weight, better still from 0.2 to to 2% by weight, even better still from 0.5 to 1.5% by weight relative to the total weight of the first composition A.
Better still, the the total content of compound(s) of amino acid type chosen from glycine, proline, methionine, serine, arginine, lysine, salts thereof and mixtures thereof, in the first composition A of the lightening agent according to the invention, can range from 0.01% to 5% by weight, preferably from 0.05 to 4% by weight, more preferably from 0.1 to 3% by weight, better still from 0.2 to 2% by weight, even better still from 0.5 to 1.5% by weight relative to the total weight of the first composition A.
Most particularly, the total content of compound(s) of amino acid type chosen from glycine, salts thereof, and mixtures thereof, in the first composition A of the lightening agent according to the invention may range from 0.01% to 5% by weight, preferably from 0.05 to 4% by weight, more preferably from 0.1 to 3% by weight, better still from 0.2 to 2% and even better still from 0.5 to 1.5% by weight relative to the total weight of the first composition A.
Even better still, the glycine content in the first composition A of the lightening agent according to the invention may range from 0.01% to 5% by weight, preferably from 0.05% to 4% by weight, more preferably from 0.1% to 3% by weight, better still from 0.2 to to 2%, even better still from 0.5 to 1.5% by weight relative to the total weight of the first composition A.

(Poly)carboxylic acids

The first composition A of the lightening agent according to the invention comprises one or more (poly)carboxylic acids other than the compound(s) of amino acid type described above, a salt thereof, or mixtures thereof.
Preferably, the (poly)carboxylic acids is (are) chosen from (poly)carboxylic acid(s) of formula (II) below:
(II)
in which formula (II):
- n is an integer between 0 and 10, better still between 1 and 5, even better still between 1 and 3; preferably, n = 1 or 2, more preferably still n = 2;
- A is a saturated or unsaturated, linear, branched, cyclic or even aromatic monovalent hydrocarbon group (when n = 0) or multivalent hydrocarbon group (when n is other than 0), comprising from 1 to 6 carbon atoms, preferably from 1 to 4 carbon atoms, optionally substituted with one or more hydroxyl groups (OH).
Preferably, A is a monovalent or multivalent (C₁-C₆)alkylene, better still (C₂-C₄)alkylene group, or phenylene group, optionally substituted with one or more hydroxyl groups.
Preferably, the (poly)carboxylic acids of formula (II) are alpha-hydroxy acids, for which A is a (C₁-C₆)alkylene, better still (C₂-C₄)alkylene group, or a phenylene group, substituted with 1 or 2 hydroxyl groups, preferably 1 hydroxyl group; and n = 0 to 2.
Mention may be made in particular of the (poly)carboxylic acids of formula (II) in which:
- n = 0 and A is a monovalent (C₁-C₆)alkyl, particularly (C₂-C₄)alkyl group, optionally substituted with one or more hydroxyl groups (OH), particularly 1 or 2 OH, preferably 1 OH;
- n = 0 and A is a phenyl radical substituted with 1 OH radical; or
- n = 1 or 2 and A is a divalent or trivalent (C₁-C₆)alkyl, better still (C₂-C₄)alkyl group, substituted with one or more hydroxyl groups, particularly 1 or 2 OH, preferably 1 OH.
Preferentially, the (poly)carboxylic acids may be chosen from:
- citric acid (n=2 and A trivalent = -CH₂-CHOH-CH₂- );
- salicylic acid (n = 0 and A = phenyl substituted with an OH);
- lactic acid (n = 0 and A monovalent = -CH(OH)CH₃); and
- tartaric acid (n = 1 and A divalent = -CH(OH)-CH(OH)-).
Even more preferentially, the (poly)carboxylic acid is citric acid.
The first composition A of the lightening agent according to the invention preferably comprises said (poly)carboxylic acid(s) and/or salts thereof in a total amount ranging from 0.1% to 15% by weight, better still from 2 to 12% by weight, preferentially from 4 to 10% by weight relative to the total weight of the first composition A.
In a preferred embodiment, the first composition A of the lightening agent according to the invention comprises citric acid in a total amount ranging from 0.1% to 15% by weight, better still from 2 to 12% by weight, preferentially from 4 to 10% by weight relative to the total weight of the first composition A.

Surfactants

The first composition A of the lightening agent according to the present invention may comprise one or more surfactants. These surfactants may preferably be chosen from anionic surfactants, amphoteric surfactants, non-ionic surfactants and cationic surfactants and/or mixtures thereof.
Preferably, the first composition A of the lightening agent according to the invention comprises one or more surfactants.
Preferably, the first composition A of the lightening agent according to the invention comprises one or more anionic surfactants.
The term "anionic surfactant" is understood to mean a surfactant including, as ionic or ionizable groups, only anionic groups. These anionic groups are preferably chosen from the groups CO₂H, CO₂ ^-, SO₃H, SO₃ ^-, OSO₃H, OSO₃ ^-, H₂PO₃, HPO₃ ^-, PO₃ ^2-, H₂PO₂, HPO₂ ^-, PO₂ ^2-, POH and PO^-.
As examples of anionic surfactants that may be used in the first composition A, mention may be made of alkyl sulfates, alkyl ether sulfates, alkylamido ether sulfates, alkylaryl polyether sulfates, monoglyceride sulfates, alkyl sulfonates, alkylamide sulfonates, alkylaryl sulfonates, α-olefin sulfonates, paraffin sulfonates, alkyl sulfosuccinates, alkyl ether sulfosuccinates, alkylamide sulfosuccinates, alkyl sulfoacetates, acyl sarcosinates, acyl glutamates, alkyl sulfosuccinamates, acyl isethionates and N-(C₁-C₄)alkyl N-acyl taurates, salts of alkyl monoesters of polyglycoside-polycarboxylic acids, acyl lactylates, salts of D-galactoside uronic acids, salts of alkyl ether carboxylic acids, salts of alkylaryl ether carboxylic acids, salts of alkylamido ether carboxylic acids; and the corresponding non-salified forms of all these compounds; the alkyl and acyl groups of all these compounds (unless specified otherwise) generally comprising from 6 to 24 carbon atoms and the aryl group generally denoting a phenyl group.
Among the anionic surfactants, mention may also be made of salts of fatty acids, particularly C₈-C₂₄ fatty acids, preferably C₁₂-C₂₀ fatty acids, other than the (poly)carboxylic acids described above.
These compounds may be oxyethylenated and then preferably comprise from 1 to 50 ethylene oxide units.
The salts of C₆-C₂₄ alkyl monoesters of polyglycoside-polycarboxylic acids may be chosen from C₆-C₂₄ alkyl polyglycoside-citrates, C₆-C₂₄ alkyl polyglycoside-tartrates and C₆-C₂₄ alkyl polyglycoside-sulfosuccinates.
When the anionic surfactant(s) are in salt form, they may be chosen from alkali metal salts such as the sodium or potassium salt and preferably the sodium salt, ammonium salts, amine salts and in particular amino alcohol salts or alkaline-earth metal salts such as the magnesium salt.
By way of example of amino alcohol salts, mention may particualrly be made of monoethanolamine, diethanolamine and triethanolamine salts, monoisopropanolamine, diisopropanolamine or triisopropanolamine salts, 2-amino-2-methyl-1-propanol salts, 2-amino-2-methyl-1,3-propanediol salts and tris(hydroxymethyl)aminomethane salts.
Use is preferably made of the alkali metal or alkaline-earth metal salts and in particular the sodium or magnesium salts.
The anionic surfactants that are optionally present may be mild anionic surfactants, i.e. anionic surfactants without a sulfate function.
As regards mild anionic surfactants, mention may be made in particular of the following compounds and salts thereof, and also mixtures thereof: polyoxyalkylenated carboxylic acid alkyl ethers; polyoxyalkylenated carboxylic acid alkylaryl ethers; polyoxyalkylenated carboxylic acid alkylamido ethers, in particular those comprising 2 to 50 ethylene oxide groups; alkyl D-galactoside uronic acids; acylsarcosinates, acylglutamates; and alkylpolyglycoside carboxylic esters.
Use may be made most particularly of polyoxyalkylenated carboxylic acid alkyl ethers, for instance the carboxylic acid lauryl ether (4.5 EO) sold, for example, under the name AKYPO RLM 45 CA from KAO.
Among the anionic surfactants mentioned above, use is preferably made of the sulfated surfactants such as the alkyl sulfates or alkyl ether sulfates, and the acyl glutamates, salts of C₁₂-C₂₀ fatty acids, more preferentially alkyl sulfates and salts of C₁₂-C₂₀ fatty acids.
According to a preferred embodiment, the first composition A of the lightening agent comprises one or more surfactants chosen from alkyl sulfates.
When the first composition A comprises one or more surfactant(s), the total content of surfactant(s) in the first composition A preferably ranges from 0.01 to 15% by weight, more preferentially from 0.1 to 10% by weight, better still from 0.5 to 5% by weight relative to the total weight of the first composition A.
When the first composition A of the lightening agent comprises one or more anionic surfactant(s), the total content of anionic surfactant(s) in the first composition A preferably ranges from 0.01 to 10% by weight, more preferentially from 0.1 to 10% by weight, better still from 0.5 to 5% by weight relative to the total weight of composition A.

Fatty substance

The first composition A of the lightening agent according to the invention may also comprise one or more fatty substances.
For the purposes of the present invention, the term "fatty substance" means an organic compound that is insoluble in water at ordinary ambient temperature (20-25°C) and at atmospheric pressure (760 mmHg, i.e. 1.013×10⁵ Pa), with a solubility in water of less than 5%, preferably less than 1% and even more preferentially less than 0.1%. The fatty substances generally have in their structure a hydrocarbon chain comprising at least 6 carbon atoms. In addition, the fatty substances are generally soluble in organic solvents under the same temperature and pressure conditions, for instance chloroform, ethanol, benzene, liquid petroleum jelly or decamethylcyclopentasiloxane.
The fatty substances are, moreover, non-(poly)oxyalkylenated and non-(poly)glycerolated. In other words, the fatty substances do not comprise in their structure a (poly)ethylene oxide or (poly)glycerol or (poly)propylene glycol unit.
The fatty substance(s) may be chosen from solid fatty substances and/or liquid fatty substances (also called "oil"), and mixtures thereof.
The term "oil" means a "fatty substance" which is liquid, i.e. which is capable of flowing under the action of its own weight at ambient temperature (25°C) and at atmospheric pressure (760 mmHg, i.e. 1.013×10⁵ Pa). Preferably, the viscosity at a temperature of 25°C and at a shear rate of 1 s^-1 of the oil is between 10^-3 Pa.s and 2 Pa.s. It may be measured using a Thermo Haake RS600 rheometer with cone-plate geometry or an equivalent machine.
For the purposes of the present invention, the term "solid fatty substance" means a fatty substance that is not liquid at ambient temperature (20-25°C) and at atmospheric pressure (760 mmHg, i.e. 1.013×10⁵ Pa), in particular a solid compound or a compound having a viscosity of greater than 2 Pa.s at a shear rate of 1 s^-1 under the conditions mentioned above.
Preferably, the fatty substance(s) are chosen from the liquid fatty substances.
Advantageously, the liquid fatty substances are chosen from:
- fatty alcohols that are liquid at ambient temperature, containing a branched and/or unsaturated carbon chain having from 12 to 26 carbon atoms, for instance cetanol, octyldodecanol, linoleyl alcohol, linolenyl alcohol, isostearyl alcohol, oleyl alcohol, 2-hexyldecanol, 2-butyloctanol or 2-undecylpentadecanol;
- C₆-C₁₆ hydrocarbons;
- hydrocarbons comprising more than 16 carbon atoms;
- silicones and
mixtures thereof.
Preferably, the fatty substance(s) are chosen from hydrocarbons comprising more than 16 carbon atoms.
Preferably, the first composition A of the lightening agent according to the invention comprises one or more fatty substances, preferentially chosen from liquid fatty substances, better still from hydrocarbons comprising more than 16 carbon atoms.
Advantageously, the total content of fatty substances, when they are present, ranges from 0.01 to 10% by weight, preferably from 0.1 to 5% by weight, preferentially from 0.2 to 3% by weight relative to the total weight of the first composition A of the lightening agent according to the invention.
Advantageously, the total content of liquid fatty substances, when they are present, ranges from 0.01 to 10% by weight, preferably from 0.1 to 5% by weight, preferentially from 0.2 to 3% by weight relative to the total weight of the first composition A of the lightening agent according to the invention.

Additional alkaline agent

The first composition A of the lightening agent may optionally comprise one or more alkaline agents other than the silicates and amino acids described above. Mention may be made in particular of alkali metal, alkaline earth metal or ammonium carbonates and hydrogen carbonates.
Preferably, the first composition A of the lightening agent according to the invention is anhydrous. The term "anhydrous composition" is understood to mean a composition which comprises little or no water, in particular less than 0.5% of water, better still less than 0.1% water, even better still less than 0.05% or even less than 0.01% of water, relative to the total weight of the first composition A. In particular, the first composition A does not comprise any water added during the preparation thereof, it being possible for any water that may be present present to be supplied by the starting materials used during the preparation of said composition A.
Preferably, the first composition A of the lightening agent is a pulverulent composition.

Additives

The first composition A of the lightening agent according to the invention may optionally comprise one or more additives, other than the compounds of the invention and among which mention may be made of anionic, non-ionic, amphoteric or cationic polymers or mixtures thereof, mineral thickening agents, antidandruff agents, anti-seborrhoeic agents, agents for preventing hair loss and/or hair regrowth agents, vitamins and pro-vitamins, including panthenol, sunscreens, mineral or organic pigments, plasticizers, solubilizers, opacifiers or pearlescent agents, antioxidants, sequestering agents, fragrances and preservatives.
Needless to say, a person skilled in the art will take care to select this or these optional additional compounds such that the advantageous properties intrinsically associated with the composition according to the invention are not, or are not substantially, adversely affected by the envisaged addition(s).
The above additives may generally be present in an amount of between 0 and 20% by weight, for each of them, relative to the total weight of the first composition.

Second composition

Chemical oxidizing agent

According to the present invention, the second composition B of the lightening agent according to the invention comprises one or more chemical oxidizing agents other than peroxygenated salts.
Preferably, the second composition B comprises one or more chemical oxidizing agents chosen from hydrogen peroxide, hydrogen peroxide-generating systems other than peroxygenated salts, and mixtures thereof.
The hydrogen peroxide-generating systems other than peroxygenated salts may be chosen from urea peroxide, polymeric complexes that can release hydrogen peroxide, oxidases, and mixtures thereof.
As examples of polymeric complexes that can release hydrogen peroxide, mention may be made of polyvinylpyrrolidone/H₂O₂ in particular in powder form, and the other polymeric complexes described in US 5 008 093, US 3 376 110 and US 5 183 901.
Oxidases can produce hydrogen peroxide in the presence of a suitable substrate, for instance glucose in the case of glucose oxidase or uric acid with uricase.
According to a preferred embodiment, the second composition B of the lightening agent according to the invention comprises hydrogen peroxide as chemical oxidizing agent.
The chemical oxidizing agent(s) other than peroxygenated salts are present in the second composition B preferably in a total content ranging from 0.1 to 50% by weight, and preferentially from 0.5 to 20% by weight, better still from 1 to 15% by weight relative to the total weight of the second composition B.
The second composition B is preferably an aqueous composition. In particular, it comprises more than 10% by weight of water, preferably more than 30% by weight of water and more advantageously still more than 50% by weight of water. Preferably, the second composition B comprises water in a content ranging from 10% to 95% by weight, preferably from 30% to 90% by weight, better still from 50% to 80% by weight relative to the total weight of the second composition B.
The second composition B preferably comprises one or more fatty substances as defined above, preferably chosen from fatty alcohols, liquid hydrocarbons comprising more than 16 carbon atoms, and mixtures thereof.
Preferably, the second composition B may also comprise surfactants, preferably chosen from anionic surfactants and non-ionic surfactants, and mixtures thereof.
The second composition B also preferably comprises one or more acidifying agents. Among the acidifying agents, mention may be made, by way of example, of mineral or organic acids, such as hydrochloric acid, orthophosphoric acid, sulfuric acid, carboxylic acids such as acetic acid, tartaric acid, citric acid or lactic acid, and sulfonic acids.
The pH of the second composition B, when it is aqueous, is preferably less than 7, preferably between 1 and 5, preferentially between 1.5 and 4.5. This pH may be adjusted to the desired value by using one or more acidifying agents, which may be chosen in particular from those described above.

Additives

The second composition B of the lightening agent according to the invention may optionally comprise one or more additives, among which mention may be made of anionic, non-ionic, amphoteric or cationic polymers or mixtures thereof, mineral thickening agents, antidandruff agents, anti-seborrhoeic agents, agents for preventing hair loss and/or hair regrowth agents, vitamins and pro-vitamins, including panthenol, sunscreens, mineral or organic pigments, plasticizers, solubilizers, opacifiers or pearlescent agents, antioxidants, sequestering agents, fragrances and preservatives.
Needless to say, a person skilled in the art will take care to select this or these optional additional compounds such that the advantageous properties intrinsically associated with the composition according to the invention are not, or are not substantially, adversely affected by the envisaged addition(s).
The above additives may generally be present in an amount of between 0 and 20% by weight, for each of them, relative to the total weight of the second composition B.

Third Composition C

The lightening agent may optionally comprise a third composition C comprising one or more alkaline agents.
Preferably, the composition C comprises one or more inorganic, organic or hybrid alkaline agent(s).
For the purposes of the present invention, the terms "alkaline agent" or "basifying agent" are used without distinction.
The mineral basifying agent(s) are preferably chosen from ammonium hydroxide, alkali metal carbonates or bicarbonates such as sodium (hydrogen)carbonate and potassium (hydrogen)carbonate, alkali metal or alkaline-earth metal phosphates such as sodium phosphates or potassium phosphates, sodium hydroxide or potassium hydroxide, and mixtures thereof.
The organic basifying agent(s) are preferably chosen from alkanolamines, amino acids, organic amines, oxyethylenated and/or oxypropylenated ethylenediamines, 1,3-diaminopropane, 1,3-diamino-2-propanol, spermine, spermidine, and mixtures thereof.
“Alkanolamine" means an organic amine comprising a primary, secondary or tertiary amine function, and one or more linear or branched C₁-C₈ alkyl groups bearing one or more hydroxyl radicals.
Organic amines chosen from alkanolamines such as monoalkanolamines, dialkanolamines or trialkanolamines comprising one to three identical or different C₁-C₄ hydroxyalkyl radicals are in particular suitable for carrying out the invention.
In particular, the alkanolamine(s) are chosen from monoethanolamine (MEA), diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, N,N-dimethylethanolamine, 2-amino-2-methyl-1-propanol, triisopropanolamine, 2-amino-2-methyl-propane-1,3-diol, 3-amino-1,2-propanediol, 3-dimethylamino-1,2-propanediol, tris(hydroxymethyl)aminomethane, and mixtures thereof, preferably monoethanolamine.
Advantageously, the amino acids are basic amino acids comprising an additional amine function. Such basic amino acids are preferably chosen from histidine, lysine, arginine, ornithine and citrulline.
The organic amine may also be chosen from organic amines of heterocyclic type. Besides histidine that has already been mentioned in the amino acids, mention may in particular be made of pyridine, piperidine, imidazole, triazole, tetrazole and benzimidazole. The organic amine may also be chosen from amino acid dipeptides. As amino acid dipeptides that may be used in the present invention, mention may particularly be made of carnosine, anserine and balenine. The organic amine may also be chosen from compounds comprising a guanidine function. As amines of this type other than arginine that may be used in the present invention, mention may particularly be made of creatine, creatinine, 1,1-dimethylguanidine, 1,1-diethylguanidine, glycocyamine, metformin, agmatine, n-amidoalanine, 3-guanidinopropionic acid, 4-guanidinobutyric acid and 2-([amino(imino)methyl]amino)ethane-1-sulfonic acid.
Use may in particular be made, as hybrid compounds, of guanidine carbonate or monoethanolamine hydrochloride.
The alkaline agent(s) useful according to the invention is (are) preferably chosen from alkanolamines such as monoethanolamine, diethanolamine and triethanolamine; ammonium hydroxide, sodium hydroxide or potassium hydroxide and mixtures thereof, more preferentially from ammonium hydroxide, alkanolamines, and mixtures thereof, more better still from ammonium hydroxide and monoethanolamine, and mixtures thereof.
The third composition C of the lightening agent according to the invention preferably comprises said alkaline agent(s) in a total amount ranging from 0.1 to 40% by weight, more preferentially from 1 to 30% by weight, better still from 2 to 25% by weight, even better still from 5 to 20% by weight relative to the total weight of the third composition C.
Preferably, the third composition C of the lightening agent according to the invention comprises said alkaline agent(s) chosen from ammonium hydroxide and monoethanolamine, and mixtures thereof, in a total amount ranging from 0.1 to 40% by weight, more preferentially from 1 to 30% by weight, better still from 2 to 25% by weight, even better still from 5 to 20% by weight relative to the total weight of composition C.
The third composition C is preferably an aqueous composition. In particular, it comprises more than 10% by weight of water, preferably more than 20% by weight, better still more than 30% by weight relative to the total weight of the third composition C. Preferably, the third composition C comprises water in a content ranging from 10% to 80% by weight, preferably from 20% to 70% by weight, better still from 30 to 60% by weight relative to the total weight of the third composition C.
The third composition C may also comprise one or more organic solvents.
By way of organic solvent, mention may for example be made of linear or branched C₂ to C₄ alkanols, such as ethanol and isopropanol; glycerol; polyols and polyol ethers such as 2-butoxyethanol, propylene glycol, dipropylene glycol, propylene glycol monomethyl ether, and diethylene glycol monoethyl ether and monomethyl ether, and also aromatic alcohols or ethers, such as benzyl alcohol or phenoxyethanol, and mixtures thereof.
Preferably, the third composition C comprises one or more organic solvents, preferably chosen from polyols, preferentially propylene glycol, and mixtures thereof.
The third composition C of the lightening agent according to the invention preferably comprises said organic solvent(s) in a total amount ranging from 1 to 40% by weight and preferably from 5 to 30% by weight relative to the weight of the third composition C.
The third composition C preferably comprises one or more fatty substances as defined above, preferably chosen from fatty alcohols and fatty alcohol esters, and mixtures thereof.
The third composition C may also comprise surfactants as defined above, preferably chosen from anionic surfactants and non-ionic surfactants, and mixtures thereof.
The pH of the third composition C, when it is aqueous, preferably ranges from 8 to 12, preferentially from 9 to 11, better still from 10 to 11. More preferentially, the pH of the third composition C is greater than or equal to 10.5, better still ranges from 10.6 to 11.

Process

The present invention also relates to a process for lightening keratin fibres, preferably human keratin fibres, particularly the hair.
The process according to the invention comprises:
(i) a step of mixing a first composition A as described above with a second composition B as described above,
(ii) a step of applying, to said keratin fibres, the composition resulting from the mixture obtained in step (i).
This mixing step is preferably performed at the time of use, just before the composition resulting from the mixing is applied to the hair.
Preferably, the first composition A and the second composition B are mixed in an A/B weight ratio ranging from 0.1 to 2, preferentially from 0.3 to 1.5, better still from 0.5 to 1.
According to one embodiment, the process according to the invention comprises:
(i) a step of mixing a first composition A as described above with a second composition B as described above and also with a third composition C as described above,
(ii) a step of applying, to said keratin fibres, the composition resulting from the mixture obtained in step (i).
Preferably, the first composition A, the second composition B and the third composition C are mixed in a weight ratio:
- A/B ranging from 0.05 to 2, preferentially from 0.1 to 1, better still from 0.2 to 0.5, and/or
- A/C ranging from 0.5 to 2, preferentially from 0.7 to 1.5, better still from 0.8 to 1, and/or
- C/B ranging from 0.05 to 2, preferentially from 0.1 to 1, better still from 0.2 to 0.5.
The composition resulting from the mixture of step (i) is referred to as a ready-to-use composition.
The present invention also relates to the ready-to-use composition obtained from mixing the first composition A and the second composition B, and optionally the third composition C, defined above.
Preferably, the pH of the ready-to-use composition ranges from 8 to 13, preferentially from 9 to 12.
The ready-to-use composition may be applied to wet or dry keratin fibres. After the treatment, the keratin fibres are optionally rinsed with water, optionally washed with a shampoo and then rinsed with water, before being dried or left to dry.

Kit

Another subject of the invention is a device with at least two compartments for lightening keratin fibres, comprising a first compartment containing a first composition A as described above and a second compartment containing a second composition B as described above.
Another subject of the invention is a device with at least three compartments for lightening keratin fibres, comprising a first compartment containing a first composition A as described above, a second compartment containing a second composition B as described above, and a third compartment containing a third composition C as described above.
The compositions A, B and optionally C of the device according to the invention are packaged in separate compartments, optionally accompanied by suitable application means, which may be identical or different, such as fine brushes, coarse brushes or sponges.
The device mentioned above may also be equipped with a means for dispensing the desired mixture on the hair, for instance the devices described in patent FR 2 586 913.
Finally, the present invention relates to the use of an agent according to the invention as described above, for lightening keratin fibres, and in particular hair.
The following examples serve to illustrate the invention without, however, exhibiting a limiting nature.

Examples

In the examples that follow, all the amounts are given as mass percentages of active material (AM) relative to the total weight of the composition (unless otherwise mentioned).

Compositions A1 and A2

Composition A1 according to the invention and comparative composition A2 were prepared using the ingredients, the contents of which are indicated in the table below:

	A1	A2
POTASSIUM PERSULFATE	42	42
AMMONIUM PERSULFATE	11.1	11.1
SODIUM PERSULFATE	4.9	4.9
Magnesium carbonate hydroxide	-	13.3
SODIUM SILICATE	28	14.7
SODIUM METASILICATE	3.3	3.3
SODIUM LAURYL SULFATE	1.5	1.5
CITRIC ACID	5.7	5.7
GLYCINE	1	1
Hydrogenated polydecene	0.5	0.5
sequestering agent, filler	qs 100	qs 100

Composition B1

Composition B1 was prepared from the ingredients of which the contents are indicated in the table below:

	B1
TETRASODIUM PYROPHOSPHATE	0.05
SODIUM SALICYLATE	0.05
PEG-40 hydrogenated castor oil	0.9
SODIUM CETEARYL SULFATE	0.45
HYDROGEN PEROXIDE	9
Cetearyl Alcohol	3.15
Mineral oil	17
TETRASODIUM ETIDRONATE	0.12
PHOSPHORIC ACID	qs pH 4.2 ± 0.2
Water/Aqua	qs 100

At the moment of use, compositions A1 and A2 were respectively mixed with composition B in a 1+2 weight ratio in order to obtain mixtures M1 and M2.
These mixtures were prepared in a bowl using a brush.
The mixture M1 according to the invention is sufficiently compact, thus allowing easy and uniform application to all hair strands.
Each of the mixtures M1 and M2 was applied to a lock of natural light chestnut-brown hair (tone height 4) in a proportion of 10 g of mixture per 1 g of lock of hair.
After a leave-on time of 45 min at 33°C, on a thermostatically controlled heating plate, the locks were rinsed, then washed and dried at 50°C in an oven for 30 minutes.

Colorimetric measurements

The lightening of the hair is evaluated in the L*a*b* system, using a Konica Minolta CM-3600A spectrocolorimeter (illuminant D65, angle 10°, specular component included) in the CIELab system.
In this system, L* represents the lightness, a* represents the green/red colour axis and b* represents the blue/yellow colour axis.
The higher the value of L, the more the lock is lightened.

Results

	L*
Control before treatment	19.10
M1	48.90
M2	43.90

The mixture M1 results in a higher value of L, and therefore better lightening of the hair than the mixture M2.

Claims

Agent for lightening keratin fibres, comprising:
a) a first composition A comprising:
- one or more peroxygenated salts,
- one or more silicates in a total content of greater than or equal to 25% by weight relative to the total weight of the first composition A,
- one more compound(s) of amino acid type,
- one or more (poly)carboxylic acids and/or salts thereof, other than the compound(s) of amino acid type;
b) a second composition B comprising one or more chemical oxidizing agent(s) other than the peroxygenated salts.
Agent according to the preceding claim, in which the peroxygenated salt(s) are chosen from alkali metal persulfates, alkaline earth metal persulfates, ammonium persulfates, and mixtures thereof; more preferentially from (bis)tetrabutylammonium persulfate, barium persulfate, magnesium persulfate, calcium persulfate, sodium persulfate, potassium persulfate, ammonium persulfate, and mixtures thereof; even more preferentially from sodium persulfate, potassium persulfate, ammonium persulfate, and mixtures thereof.
Agent according to either one of the preceding claims, in which the total content of peroxygenated salt(s) in the first composition A ranges from 1 to 80% by weight, preferably from 10 to 70% by weight, more preferentially from 20 to 65% by weight, better still from 30 to 60% by weight relative to the total weight of the first composition A.
Agent according to any one of the preceding claims, in which the first composition A comprises one or more silicates chosen from alkali metal silicates, alkaline earth metal silicates, aluminium silicates, trimethylammonium silicates and mixtures thereof, preferably from sodium silicates, potassium silicates, calcium silicates, aluminium silicates, trimethylammonium silicates and mixtures thereof, more preferentially from sodium silicates, even more preferentially from compounds having the INCI name Sodium Silicate and/or Sodium Metasilicate.
Agent according to any one of the preceding claims, in which the total content of the silicate(s) ranges from 25 to 50% by weight, more preferentially from 27 to 40% by weight, better still from 29 to 35% by weight relative to the total weight of the first composition A.
Agent according to any one of the preceding claims, in which the compound(s) of amino acid type are chosen from compounds of formula (I), salts thereof and mixtures thereof:
(I)
in which formula (I):
▪ p is an integer equal to 1 or 2; it being understood that:
▪ when p = 1, R forms, with the nitrogen atom, a saturated heterocycle comprising from 5 to 8 ring members, preferably 5 ring members, it being possible for this ring to be optionally substituted with at least one group chosen from hydroxyl or (C₁-C₄)alkyl;
▪ when p = 2, R represents:
- a hydrogen atom; or
- a saturated, linear or branched, (C₁-C₁₂)alkyl group, preferably a (C₁-C₄)alkyl group, optionally interrupted with at least one heteroatom or group chosen from –S–, –NH– or –C(NH)– and/or optionally substituted with at least one group chosen from hydroxyl (-OH), amino (-NH₂), -SH, -COOH, -CONH₂ or –NH–C(NH)–NH₂.
Agent according to any one of the preceding claims, in which the compound(s) of amino acid type are chosen from glycine, proline, methionine, serine, arginine, lysine, salts thereof and mixtures thereof, preferably from glycine, proline, methionine, serine, salts thereof and mixtures thereof, more preferentially from glycine, salts thereof and mixtures thereof; even more preferentially, the amino acid is glycine.
Agent according to any one of the preceding claims, in which the compound(s) of amino acid type are present in the first composition A in a total amount ranging from 0.01% to 5% by weight, preferably from 0.05 to 4% by weight, more preferably from 0.1 to 3% by weight, better still from 0.2 to 2% by weight, even better still from 0.5 to 1.5% by weight relative to the total weight of the first composition A.
Agent according to any one of the preceding claims, in which the first composition A comprises one or more (poly)carboxylic acids other than the compound(s) of amino acid type,corresponding to formula (II) below:
(II)
in which:
- n is an integer between 0 and 10, better still between 1 and 5, even better still between 1 and 3; preferably, n = 1 or 2, more preferably still n = 2;
- A is a saturated or unsaturated, linear, branched, cyclic or even aromatic monovalent (when n=0) or multivalent (when n is other than 0) hydrocarbon group comprising from 1 to 6 carbon atoms, preferably from 1 to 4 carbon atoms, optionally substituted with one or more hydroxyl groups (OH); A preferably being a monovalent or multivalent (C₁-C₆)alkylene, better still (C₂-C₄)alkylene, or phenylene group, optionally substituted with one or more hydroxyl groups;
in particular corresponding to formula (II) in which A is a (C₁-C₆)alkylene, better still (C₂-C₄)alkylene, or phenylene group, substituted with 1 or 2 hydroxyl groups, preferably 1 hydroxyl group; and n = 0 to 2;
even better still of formula (II) in which
- n = 0 and A is a monovalent (C₁-C₆)alkyl, particularly (C₂-C₄)alkyl group, optionally substituted with one or more hydroxyl groups (OH), particularly 1 or 2 OH, preferably 1 OH;
- n = 0 and A is a phenyl radical substituted with 1 OH radical; or
- n = 1 or 2 and A is a divalent or trivalent (C₁-C₆)alkyl, better still (C₂-C₄)alkyl group, substituted with one or more hydroxyl groups, particularly 1 or 2 OH, preferably 1 OH;
preferentially chosen from citric acid, salicylic acid, lactic acid and tartaric acid; more preferentially citric acid.
Agent according to one of the preceding claims, in which the total content of (poly)carboxylic acids, preferably citric acid, in the first composition A ranges from 0.1% to 15% by weight, better still from 2 to 12% by weight, preferentially from 4 to 10% by weight relative to the total weight of the first composition A.
Agent according to any one of the preceding claims, in which the first composition A is anhydrous.
Agent according to any one of the preceding claims, in which the first composition A is a pulverulent composition.
Agent according to any one of the preceding claims, in which the second composition B, which is preferably aqueous, comprises a chemical oxidizing agent chosen from hydrogen peroxide, hydrogen peroxide-generating systems other than peroxygenated salts, and mixtures thereof.
Agent according to any one of the preceding claims, comprising a third composition C comprising one or more alkaline agents, preferably chosen from alkanolamines such as monoethanolamine, diethanolamine, triethanolamine; ammonium hydroxide, sodium hydroxide or potassium hydroxide, and mixtures thereof, more preferentially from ammonium hydroxide, alkanolamines and mixtures thereof, better still from ammonium hydroxide, monoethanolamine and mixtures thereof.
Ready-to-use composition obtained by mixing the first composition A with the second composition B, and optionally the third composition C, as defined in any one of Claims 1 to 14.
Process for lightening keratin fibres, preferably human keratin fibres, in particular the hair, comprising (i) a step of mixing the first composition A with the second composition B, and optionally the third composition C, as defined in any one of Claims 1 to 14, (ii) a step of applying, to said keratin fibres, the composition resulting from the mixture obtained in step (i).
Use of a composition obtained from mixing the first composition A with the second composition B, and optionally the third composition C, as defined in any one of Claims 1 to 14, for lightening keratin fibres, and in particular the hair.