Oxidative hair brightening by means of persulfate, dicarboxylic acid, and citrulline

Abstract

The present invention relates to color-changing agents which act in particular as agents for brightening keratin fibers, in particular human hair. The present invention also relates to the use of the agents for gently bleaching or oxidatively brightening human hair, and to a multi-component packaging unit (kit of parts) for brightening keratin fibers, which comprises an anhydrous, persulfate-containing color-changing agent containing citrulline and at least one dicarboxylic acid having 2-10 carbon atoms, and which comprises, separate therefrom, an oxidizing agent preparation.

Description

[0001] Henkel AG & Co. KGaA

[0002] 04.09.2025

[0003] 2024P00117WG

[0004] "Color-changing agents and methods for gentle oxidative hair lightening"

[0005] The present invention relates to color-changing agents, which serve in particular as agents for lightening keratinous fibers, especially human hair. Furthermore, the present invention relates to the use of the agents for the gentle bleaching or oxidative lightening of human hair, as well as a multi-component packaging unit (kit-of-parts) for lightening keratinous fibers, comprising an anhydrous, persulfate-containing color-changing agent with a citrulline content and, separately, an oxidizing agent preparation.

[0006] Furthermore, a method for the oxidative lightening of keratinous fibers using the aforementioned color-changing agent and the kit comprising this color-changing agent is described.

[0007] The color-changing agent according to the invention can be in the form of a bleaching powder, i.e., an anhydrous, persulfate-containing powder, or a bleaching paste, i.e., an anhydrous, oil-based paste.

[0008] Lightening one's hair color has always been a desire for many consumers, as blonde hair is considered attractive and fashionable. Various bleaching agents with different levels of lightening power are available on the market for this purpose. The oxidizing agents contained in these products lighten the hair fiber by oxidatively destroying the hair's natural pigment, melanin. For a moderate bleaching effect, hydrogen peroxide—possibly with the addition of ammonia or other alkalizing agents—is sufficient as the oxidizing agent alone. To achieve a stronger bleaching effect, a mixture of hydrogen peroxide and at least one persulfate is typically used. To enhance the bleaching effect, these products contain higher concentrations of hydrogen peroxide and persulfate(s).Dark, dark brown, or black hair can be lightened by 4 to 6 shades in one step. The hydrogen peroxide-containing component and the persulfate-containing component are stored separately until use to prevent premature deactivation of the persulfates. The hydrogen peroxide component, which comprises an aqueous solution of hydrogen peroxide, has an acidic pH value, specifically a pH value of 2.5 to 5.5, and particularly 3 to 5, measured at 20°C, to stabilize the hydrogen peroxide.

[0009] However, for the melanin-degrading effect of hydrogen peroxide and the bleaching effect on the keratinous fiber, it is advantageous if the application mixture of hydrogen peroxide solution and persulfate has an alkaline pH value, preferably in the range of 8 to 12, particularly preferably in the range of 8.5 to 11.5, and most preferably in the range of 9 to 10.5, each measured at 20°C.

[0010] There are several ways to adjust the pH of the brightening application mixture to an alkaline level:

[0011] - the color-changing agent according to the invention or preferably according to the invention, in particular the bleaching powder or the bleaching paste, contains, in addition to the at least one persulfate, at least one powdered alkalizing agent in such a total amount that the application mixture has the desired alkaline pH value; or

[0012] - the hydrogen peroxide solution is combined not only with the color-changing agent according to the invention or preferred according to the invention, in particular the bleaching powder or bleaching paste, but also with an alkalizing agent preparation to form the application mixture.

[0013] Adding oxidation dye precursors and / or direct dyes to the alkalizing agent and / or the color-changing agent allows for simultaneous hair coloring. Corresponding three-component hair dyes are offered particularly for consumers with very dark, melanin-rich hair.

[0014] However, bleaching also damages the hair, as not only the hair's pigments but also its structural components are oxidatively damaged. Depending on the degree of damage, this ranges from rough, brittle, and difficult-to-comb hair to reduced resilience and tensile strength, and even breakage. Therefore, the greater the amount of hydrogen peroxide and, if applicable, persulfates used, the more severe the damage is generally caused to the keratin fibers.

[0015] In order to minimize hair damage and counteract the damaging effect of oxidizing agents, attempts are constantly being made to formulate persulfate-containing hair lightening and dyeing products with a higher oil content.

[0016] Prior art describes, for example, bleaching agent suspensions that are anhydrous suspensions of finely divided persulfates, solid at 25°C and 1013 mbar, in an oil or oil mixture, which may optionally be thickened with an oil gelling agent (see EP 778020 A1, EP 1034777 A1, and EP 1380287 A1). A disadvantage of this approach is that producing a homogeneous mixture from this highly hydrophobic paste and the highly aqueous hydrogen peroxide preparation, as well as the typically aqueous alkalizing agent preparation, is difficult and requires prolonged, vigorous shaking or stirring. Furthermore, producing a bleaching agent suspension is technically more complex than producing a powdered persulfate-containing mixture.

[0017] The object of the present invention was therefore to provide agents for lightening or bleaching keratinous fibers, in particular human hair, which cause as little damage to the keratin fibers as possible and which are easy to manufacture and handle. The reduction of fiber damage should be achieved, if possible, not through oils, but through alternative conditioning agents.

[0018] Surprisingly, these tasks were solved by the subject matter of the claims.

[0019] According to the invention, keratin-containing or keratinous fibers are understood to be furs, wool, feathers, and especially human hair. Although the compositions according to the invention are primarily suitable for bleaching and / or lightening keratin-containing fibers, there is nothing in principle to preclude their use in other areas as well.

[0020] A suitable parameter for quantifying fiber damage, especially hair damage, is the measurement of the tensile strength (Young's modulus) of the keratin fibers.

[0021] WO 2005 / 115314A1 discloses a process for restructuring keratin fibers, in which the keratin fibers are brought into contact with cystine and with at least one dicarboxylic acid having 2 to 10 carbon atoms, wherein preferred dicarboxylic acids are selected from oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, maleic acid, fumaric acid, and sorbic acid, with succinic acid being particularly preferred. DE10051774 A1 describes the use of short-chain carboxylic acids with a molecular weight below 750 g / mol in cosmetic products as an active ingredient for restructuring keratin fibers. EP1174112A discloses hair treatment products which, in addition to an organic acid, contain as further essential components an organic solvent, a cationic surfactant, and a higher alcohol, and which serve to repair pores in hair.

[0022] EP3463582A1 and EP3463583A1 disclose bleaching powders and bleaching pastes for the gentle oxidative lightening of keratin fibers, containing a combination of a dicarboxylic acid, preferably succinic acid, and at least one amino acid selected from arginine, lysine and histidine.

[0023] However, the compositions of the state of the art still need improvement in their effect on restructuring and damage minimization while simultaneously achieving good brightening results.

[0024] The present invention was based on the objective of providing a color-changing agent for keratin fibers, in particular for the oxidative brightening of keratin fibers, which causes the least possible fiber damage without impairing the result of the color change, in particular the result of the brightening, of the fibers.

[0025] Surprisingly, it was found that the degree of damage to keratin fibers during oxidative lightening was significantly reduced by the addition of citrulline in combination with at least one dicarboxylic acid with 2 to 10 carbon atoms to a persulfate-containing color-changing agent for keratin fibers, compared to oxidative lightening with a persulfate-containing color-changing agent without either of these active ingredient combinations. At the same time, no impairment of the color-changing result, particularly the lightening result, was observed in the fibers (2024P00117WÖ 4).

[0026] A first object of the present invention is an agent for oxidative color change, in particular for lightening, of keratinous fibers, in particular human hair, comprising a) at least one persulfate selected from the group consisting of sodium peroxodisulfate, potassium peroxodisulfate and ammonium peroxodisulfate and mixtures thereof, and b) citrulline and c) at least one dicarboxylic acid having 2 to 10 carbon atoms and d) 0 to 12 wt% water, based on the weight of the color-changing agent.

[0027] As mentioned above, the color-changing agent according to the invention can be in the form of a bleaching powder, i.e., an anhydrous, persulfate-containing powder, or a bleaching paste, i.e., an anhydrous, oil-based paste.

[0028] According to the invention, the terms "powder" or "powder-like" refer to a free-flowing dosage form consisting of individual particles that is solid at 20 °C and 1013 mbar, with individual particles having sizes ranging from 0.1 mm to a maximum of 1.6 mm. The particle sizes can preferably be determined by laser diffraction measurement according to ISO 13320-1 (2020). Optionally, the particle size can be adjusted to meet the requirements of the bleaching powder by physical treatment such as sieving, pressing, granulation, or pelletizing, or by the addition of specific additives, in order to, for example, improve the miscibility of the individual powder components or the miscibility of the bleaching powder with a hydrogen peroxide preparation.

[0029] According to the invention, preferred bleaching powders have a bulk density in the range of 400 to 1000 g / l (grams / liter), preferably 450 to 900 g / l, and particularly preferably 600 to 820 g / l. The bulk density is preferably determined according to EN ISO 60 or DIN 53468.

[0030] Unless otherwise stated, all temperature specifications refer to a pressure of 1013 mbar.

[0031] Bleaching pastes are essentially anhydrous and optionally thickened suspensions of powdered persulfates and optionally powdered alkalizing agent(s) in an oil or oil mixture.

[0032] According to the invention, the terms "paste" or "paste-like" are to be understood as a dosage form which, at 20 °o and 1013 mbar, has a viscosity in the range of 200,000 to 1,600,000 mPas, preferably 250,000 to 1,400,000 mPas, particularly preferably 300,000 to 1,000,000 mPas, and most preferably 400,000 to 750,000 mPas.

[0033] The paste viscosity is preferably determined using a Brookfield instrument; RVDV II+; spindle 2024P00117WC 5

[0034] No. 96, 4 revolutions per minute, at 20°C.

[0035] Unless otherwise stated, all temperature specifications refer to a pressure of 1013 mbar.

[0036] The color-changing agent according to the invention, preferably the bleaching powder or the bleaching paste, contains as a first essential component at least one persulfate selected from the group consisting of sodium peroxodisulfate, potassium peroxodisulfate and ammonium peroxodisulfate as well as mixtures thereof.

[0037] Ammonium peroxodisulfate, which can alternatively also be called ammonium persulfate, is understood to be the persulfate with the molecular formula (NH4)2S20s.

[0038] Potassium peroxodisulfate, which can alternatively also be called potassium persulfate, refers to the persulfate with the molecular formula K2S2O8.

[0039] Sodium peroxodisulfate, which can alternatively also be called sodium persulfate, refers to the persulfate with the molecular formula Na2S20s.

[0040] The color-changing agent according to the invention can contain one of the persulfates, mixtures of two persulfates, or all three persulfates. In the work carried out on the present invention, it has proven particularly preferred if the color-changing agent contains at least two different peroxodisulfates. Preferred peroxodisulfate salts are combinations of ammonium peroxodisulfate and potassium peroxodisulfate and / or sodium peroxodisulfate.

[0041] Preferred color-changing agents according to the invention, preferably bleaching powders or bleaching pastes, contain at least one persulfate selected from the group consisting of sodium peroxodisulfate, potassium peroxodisulfate and ammonium peroxodisulfate and mixtures thereof, in a total amount of 5 - 85 wt.%, preferably 10 - 75 wt.%, particularly preferably 15 - 65 wt.%, extraordinarily preferably 20 - 55 wt.%, further extraordinarily preferably 25 to 50 wt.% and particularly 30 to 45 wt.%, in each case based on the weight of the color-changing agent.

[0042] The color-changing agent according to the invention, preferably the bleaching powder or the bleaching paste, contains citrulline as a second essential component.

[0043] Citrulline possesses a stereogenic center. Both the (S)-form and the (R)-form (or both the L-form and the D-form) are according to the invention. Naturally occurring L-(+)-citrulline is preferred according to the invention.

[0044] Particularly good results were achieved when the color-changing agent according to the invention contains citrulline in an amount of 0.1 to 2 wt.%, preferably 0.2 to 1 wt.%, based on the weight of the color-changing agent.

[0045] Preferred color-changing agents according to the invention are therefore characterized in that citrulline is contained in an amount of 0.1 to 2 wt.%, preferably 0.2 to 1 wt.%, particularly preferably 0.4 to 0.8 wt.%, based on the weight of the color-changing agent. 2024P00117WC 6

[0046] The color-changing agents according to the invention, preferably bleaching powders or bleaching pastes, have a water content of 0 to 12 wt.%, preferably 0.1 to 10 wt.%, and particularly preferably 1 to 9 wt.% water, in each case based on the weight of the color-changing agent. These values ​​refer to the content of free water and water of crystallization that individual powder components may contain. The water content can be determined, for example, by Karl Fischer titration in accordance with ISO 4317 (version 2011-12).

[0047] To support the damage-minimizing effect of citrulline, the color-changing agent according to the invention, preferably the bleaching powder or bleaching paste, further contains at least one dicarboxylic acid with 2 to 10 carbon atoms. In a preferred embodiment according to the invention, the dicarboxylic acid with 2 to 10 carbon atoms is selected from succinic acid, malic acid, oxalic acid, malonic acid, adipic acid, pimelic acid, cortic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, D-tartaric acid, L-tartaric acid, meso-tartaric acid, racemic acid, alpha-ketoglutaric acid, beta-ketoglutaric acid, oxaloacetic acid, and / or at least one salt of these acids, as well as mixtures of these compounds, wherein the at least one dicarboxylic acid with 2 to 10 carbon atoms is particularly preferably selected from succinic acid, malic acid, and maleic acid, as well as their salts, wherein succinic acid and / or at least one salt of succinic acid are exceptionally preferably included.

[0048] Suitable salts of dicarboxylic acids with 2 to 10 carbon atoms according to the invention are selected from the mono- and disalts of succinic acid, malic acid, oxalic acid, malonic acid, adipic acid, pimelic acid, corticic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, D-tartaric acid, L-tartaric acid, meso-tartaric acid, racemic acid, alpha-ketoglutaric acid, beta-ketoglutaric acid and oxaloacetic acid with ammonium ions, alkali metal ions, alkaline earth metal ions and the ions of basic amino acids, such as arginine, lysine and histidine, in particular with lithium, sodium, potassium, magnesium and calcium ions, as well as mixtures of these salts.

[0049] The succinic acid particularly preferred according to the invention has a melting point in the range of 185–187 °C at 1013 mbar, and is therefore a solid at 20 °C. Suitable salts of succinic acid according to the invention are selected from the succinates and hydrogen succinates of ammonium ions, alkali metal ions, alkaline earth metal ions, and the ions of basic amino acids, such as arginine, lysine, and histidine, in particular the lithium, sodium, potassium, magnesium, and calcium ions, or the succinates and hydrogen succinates of basic amino acids, such as arginine, lysine, and / or histidine, e.g., arginine succinate, as well as mixtures of these salts. The aforementioned salts of succinic acid may also contain bound water of crystallization, in particular sodium succinate hexahydrate, which is particularly preferred according to the invention.

[0050] The malic acid particularly preferred according to the invention is optically active. Racemic DL-malic acid has a melting point in the range of 131–132 °C at 1013 mbar, and is therefore a solid at 20 °C. The enantiomers D-malic acid and L-malic acid each have a melting point in the range of 100–101 °C at 1013 mbar. For cost reasons, racemic DL-malic acid is preferred. 2024P00117WC 7

[0051] Suitable malic acid salts according to the invention are selected from the malates and hydrogen malates of ammonium ions, alkali metal ions, alkaline earth metal ions, and the ions of basic amino acids, such as arginine, lysine, and histidine, in particular lithium, sodium, potassium, magnesium, and calcium ions, as well as mixtures of these salts, especially disodium malate and dipotassium malate, but also calcium malate. The aforementioned suitable malic acid salts according to the invention may contain bound water of crystallization, in particular disodium malate hemihydrate and disodium malate trihydrate.

[0052] The oxalic acid preferred according to the invention has a melting point of 189.5 °C (anhydrous) at 1013 mbar or, as a dihydrate, a melting point of 101.5 °C. Suitable salts of oxalic acid according to the invention are selected from the oxalates and hydrogen oxalates of ammonium ions, alkali metal ions, alkaline earth metal ions, and the ions of basic amino acids, such as arginine, lysine, and histidine, in particular lithium, sodium, potassium, magnesium, and calcium ions, as well as mixtures of these salts.

[0053] The malonic acid preferred according to the invention has a melting point of 135 °C at 1013 mbar. Suitable salts of malonic acid according to the invention are selected from the malates and hydrogen malates of ammonium ions, alkali metal ions, alkaline earth metal ions and the ions of basic amino acids, such as arginine, lysine and histidine, in particular lithium, sodium, potassium, magnesium and calcium ions, as well as mixtures of these salts.

[0054] The adipic acid preferred according to the invention has a melting point of 152 °C at 1013 mbar. Suitable salts of adipic acid according to the invention are selected from the adipates and hydrogen adipates of ammonium ions, alkali metal ions, alkaline earth metal ions and the ions of basic amino acids, such as arginine, lysine and histidine, in particular lithium, sodium, potassium, magnesium and calcium ions, as well as mixtures of these salts.

[0055] The pimelic acid preferred according to the invention has a melting point of 105°C at 1013 mbar. Suitable salts of pimelic acid according to the invention are selected from the pimelates and hydrogen pimelates of ammonium ions, alkali metal ions, alkaline earth metal ions and the ions of basic amino acids, such as arginine, lysine and histidine, in particular of lithium, sodium, potassium, magnesium and calcium ions, as well as mixtures of these salts.

[0056] The corkic acid preferred according to the invention has a melting point of 144 °C at 1013 mbar. Suitable salts of corkic acid according to the invention are selected from the sub-sub ...

[0057] The azelaic acid preferred according to the invention has a melting point of 106°C at 1013 mbar. Suitable salts of azelaic acid according to the invention are selected from the azelates and hydrogen azelates of ammonium ions, alkali metal ions, alkaline earth metal ions and the ions of basic amino acids, such as arginine, lysine and histidine, in particular lithium, sodium, potassium, magnesium and calcium ions, as well as mixtures of these salts.

[0058] The sebacic acid preferred according to the invention has a melting point of 2024P00117WC 8 at 1013 mbar.

[0059] 134.5 °C. According to the invention, suitable salts of sebacic acid are selected from the sebacates and hydrogen sebacates of ammonium ions, alkali metal ions, alkaline earth metal ions and the ions of basic amino acids, such as arginine, lysine and histidine, in particular lithium, sodium, potassium, magnesium and calcium ions, as well as mixtures of these salts.

[0060] The maleic acid particularly preferred according to the invention has a melting point of 130 to 131°C (from ethanol or benzene) and of 138 to 139°C (from water) at 1013 mbar. Suitable salts of maleic acid according to the invention are selected from the maleates and hydrogen maleates of ammonium ions, alkali metal ions, and alkaline earth metal ions, in particular lithium, sodium, potassium, magnesium, and calcium ions, as well as mixtures of these salts.

[0061] The fumaric acid particularly preferred according to the invention has a melting point of 287°C in the sealed tube at 1013 mbar; fumaric acid sublimates at 200°C. Suitable salts of fumaric acid according to the invention are selected from the fumarates and hydrogen fumarates of ammonium ions, alkali metal ions, and alkaline earth metal ions, in particular lithium, sodium, potassium, magnesium, and calcium ions, as well as mixtures of these salts.

[0062] The D-tartaric acid (levorotatory) particularly preferred according to the invention has a melting point of 168–170°C at 1013 mbar. Suitable salts of D-tartaric acid according to the invention are selected from the tartrates and hydrogen tartrates of ammonium ions, alkali metal ions, and alkaline earth metal ions, in particular lithium, sodium, potassium, magnesium, and calcium ions, as well as mixtures of these salts.

[0063] The L-tartaric acid (dextrorotatory) particularly preferred according to the invention has a melting point of 168–170°C at 1013 mbar. Suitable salts of L-tartaric acid according to the invention are selected from the tartrates and hydrogen tartrates of ammonium ions, alkali metal ions, and alkaline earth metal ions, in particular lithium, sodium, potassium, magnesium, and calcium ions, as well as mixtures of these salts.

[0064] The meso-tartaric acid particularly preferred according to the invention has a melting point of 140°C at 1013 mbar. Suitable salts of meso-tartaric acid according to the invention are selected from the tartrates and hydrogen tartrates of ammonium ions, alkali metal ions and alkaline earth metal ions, in particular of lithium, sodium, potassium, magnesium and calcium ions, as well as mixtures of these salts.

[0065] The racemic acid particularly preferred according to the invention is the racemic mixture of D-tartaric acid and L-tartaric acid. Racemic acid has a melting point of 206°C at 1013 mbar. Suitable salts of racemic acid according to the invention are selected from the tartrates and hydrogen tartrates of ammonium ions, alkali metal ions, and alkaline earth metal ions, in particular lithium, sodium, potassium, magnesium, and calcium ions, as well as mixtures of these salts.

[0066] The alpha-ketoglutaric acid particularly preferred according to the invention has a melting point of 112–116 °C at 1013 mbar. Suitable salts of alpha-ketoglutaric acid according to the invention are selected from the alpha-ketoglutarates and alpha-ketohydrogenglutarates of ammonium ions, alkali metal ions, and alkaline earth metal ions, in particular lithium, sodium, potassium, magnesium, and calcium ions, as well as mixtures of these salts. 2024P00117WC 9

[0067] The beta-ketoglutaric acid particularly preferred according to the invention has a melting point of 122 °C at 1013 mbar; it melts with decomposition. Suitable salts of beta-ketoglutaric acid according to the invention are selected from the beta-ketoglutarates and beta-ketohydrogenglutarates of ammonium ions, alkali metal ions and alkaline earth metal ions, in particular lithium, sodium, potassium, magnesium and calcium ions, as well as mixtures of these salts.

[0068] The oxaloacetic acid particularly preferred according to the invention has a melting point of 161 °C at 1013 mbar. Suitable salts of oxaloacetic acid according to the invention are selected from the oxal acetates and oxal hydrogen acetates of ammonium ions, alkali metal ions and alkaline earth metal ions, in particular lithium, sodium, potassium, magnesium and calcium ions, as well as mixtures of these salts.

[0069] According to the invention, preferred color-changing agents, preferably bleaching powders or bleaching pastes, contain the at least one dicarboxylic acid with 2 to 10 carbon atoms in a total amount of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and most preferably 0.9 - 1.5 wt.%, based on the weight of the color-changing agent.

[0070] According to the invention, preferred color-changing agents, preferably bleaching powders or bleaching pastes, contain at least one dicarboxylic acid with 2 to 10 carbon atoms, selected from succinic acid, malic acid, oxalic acid, malonic acid, adipic acid, pimelic acid, corticic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, D-tartaric acid, L-tartaric acid, meso-tartaric acid, racemic acid, alpha-ketoglutaric acid, beta-ketoglutaric acid, oxaloacetic acid and / or at least one salt of these acids, in a total amount of free dicarboxylic acid, converted to the mass of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and most preferably 0.9 - 1.5 wt.%, in each case based on the weight of the color-changing agent.

[0071] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain succinic acid and / or at least one salt of succinic acid in a total amount of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and extraordinarily preferably 0.9 - 1.5 wt.%, based on the weight of the color-changing agent.

[0072] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain malic acid and / or at least one salt of malic acid in a total amount of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and extraordinarily preferably 0.9 - 1.5 wt.%, based on the weight of the color-changing agent.

[0073] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain maleic acid and / or at least one salt of maleic acid in a total amount of 0.03 - 7 wt.% converted to the mass of free dicarboxylic acid, preferably 0.1 2024P00117WG 10

[0074] - 5 wt.%, particularly preferably 0.5 - 3 wt.%, extraordinarily preferably 0.9 - 1.5 wt.%, each based on the weight of the color-changing agent.

[0075] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain fumaric acid and / or at least one salt of fumaric acid in a total amount of 0.03 - 7 wt.%, preferably 0.1, converted to the mass of free dicarboxylic acid.

[0076] - 5 wt.%, particularly preferably 0.5 - 3 wt.%, extraordinarily preferably 0.9 - 1.5 wt.%, each based on the weight of the color-changing agent.

[0077] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain oxalic acid and / or at least one salt of oxalic acid in a total amount of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and extraordinarily preferably 0.9 - 1.5 wt.%, based on the weight of the color-changing agent.

[0078] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain malonic acid and / or at least one salt of malonic acid in a total amount of 0.03–7 wt.%, preferably 0.1%, converted to the mass of free dicarboxylic acid.

[0079] - 5 wt.%, particularly preferably 0.5 - 3 wt.%, extraordinarily preferably 0.9 - 1.5 wt.%, each based on the weight of the color-changing agent.

[0080] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain adipic acid and / or at least one salt of adipic acid in a total amount of 0.03 - 7 wt.%, preferably 0.1%, converted to the mass of free dicarboxylic acid.

[0081] - 5 wt.%, particularly preferably 0.5 - 3 wt.%, extraordinarily preferably 0.9 - 1.5 wt.%, each based on the weight of the color-changing agent.

[0082] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain pimelic acid and / or at least one salt of pimelic acid in a total amount of 0.03–7 wt.%, preferably 0.1%, converted to the mass of free dicarboxylic acid.

[0083] - 5 wt.%, particularly preferably 0.5 - 3 wt.%, extraordinarily preferably 0.9 - 1.5 wt.%, each based on the weight of the color-changing agent.

[0084] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain cortic acid and / or at least one salt of cortic acid in a total amount of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and extraordinarily preferably 0.9 - 1.5 wt.%, based on the weight of the color-changing agent.

[0085] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain azelaic acid and / or at least one salt of azelaic acid in a total amount of 0.03–7 wt.%, preferably 0.1%, converted to the mass of free dicarboxylic acid.

[0086] - 5 wt.%, particularly preferably 0.5 - 3 wt.%, extraordinarily preferably 0.9 - 1.5 wt.%, each based on the weight of the color-changing agent.

[0087] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain sebacic acid and / or at least one salt of sebacic acid in a total amount of 0.03 - 7 wt.%, preferably 0.1%, converted to the mass of free dicarboxylic acid.

[0088] - 5 wt.%, particularly preferably 0.5 - 3 wt.%, extraordinarily preferably 0.9 - 1.5 wt.%, each based on the weight of the color-changing agent.

[0089] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain D-tartaric acid and / or at least one salt of D-tartaric acid in a total amount of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and most preferably 0.9 - 1.5 wt.%, based on the weight of the color-changing agent.

[0090] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain L-tartaric acid and / or at least one salt of L-tartaric acid in a total amount of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and most preferably 0.9 - 1.5 wt.%, based on the weight of the color-changing agent.

[0091] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain meso-tartaric acid and / or at least one salt of meso-tartaric acid in a total amount of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and extraordinarily preferably 0.9 - 1.5 wt.%, based on the weight of the color-changing agent.

[0092] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain tartaric acid and / or at least one salt of tartaric acid in a total amount of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and extraordinarily preferably 0.9 - 1.5 wt.%, based on the weight of the color-changing agent.

[0093] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain alpha-ketoglutaric acid and / or at least one salt of alpha-ketoglutaric acid in a total amount of 0.03, converted to the mass of free dicarboxylic acid.

[0094] - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, extraordinarily preferably 0.9 - 1.5 wt.%, each based on the weight of the color-changing agent.

[0095] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain beta-ketoglutaric acid and / or at least one salt of beta-ketoglutaric acid in a total amount of 0.03, converted to the mass of free dicarboxylic acid.

[0096] - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, extraordinarily preferably 0.9 - 1.5 wt.%, each based on the weight of the color-changing agent.

[0097] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain oxaloacetic acid and / or at least one salt of oxaloacetic acid in a total amount of 0.03–7 wt.%, preferably 0.1–5 wt.%, particularly preferably 0.5–3 wt.%, and most preferably 0.9–1.5 wt.%, based on the weight of the color-changing agent. Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, additionally contain arginine or at least one salt of arginine.Among the salts of arginine that are preferably suitable according to the invention are the ammonium salts, alkali metal salts and alkaline earth metal salts, in particular the lithium, sodium, potassium, magnesium and calcium salts, also the hydrohalides, in particular the hydrochlorides, also the salts with at least one of the aforementioned dicarboxylic acids with 2 to 10 carbon atoms, as well as mixtures of these salts.

[0098] According to the invention, preferred color-changing agents, preferably bleaching powders or bleaching pastes, contain arginine or at least one salt of arginine in a total amount of 0.1 - 7 wt.%, preferably 0.2 - 5 wt.%, particularly preferably 0.5 - 2.5 wt.%, and most preferably 1 - 2 wt.%, based on the weight of the color-changing agent.

[0099] The combination of citrulline, succinic acid, and arginine has proven to be exceptionally preferred according to the invention. The combination of citrulline, disodium succinate, and arginine is also exceptionally preferred.

[0100] According to the invention, particularly preferred color-changing agents, preferably bleaching powders or bleaching pastes, contain succinic acid and / or at least one succinic acid salt in a total amount of 0.03–7 wt.%, preferably 0.05–5 wt.%, particularly preferably 0.1–3.0 wt.%, and most preferably 0.2–1.5 wt.%, based on the weight of the color-changing agent, as well as arginine or at least one salt of arginine in a total amount of 0.1–7 wt.%, preferably 0.2–5 wt.%, particularly preferably 0.5–2.5 wt.%, and most preferably 1–2 wt.%, based on the weight of the color-changing agent.

[0101] The combination of citrulline, malic acid, and arginine has proven to be exceptionally preferred according to the invention. The combination of citrulline, disodium malate, and arginine is also exceptionally preferred.

[0102] Particularly preferred color-changing agents according to the invention, preferably bleaching powders or bleaching pastes, contain malic acid and / or at least one malic acid salt in a total amount, converted to the mass of free dicarboxylic acid, of 0.03–7 wt.%, preferably 0.05–5 wt.%, particularly preferably 0.1–3.0 wt.%, and most preferably 0.2–1.5 wt.%, in each case based on the weight of the color-changing agent, and furthermore arginine or at least one salt of arginine in a total amount, converted to the mass of free amino acid, of 0.1–7 wt.%, preferably 0.2–5 wt.%, particularly preferably 0.5–2.5 wt.%, and most preferably 1–2 wt.%, in each case based on the weight of the color-changing agent. 2024P00117WG 13

[0103] To support the damage-minimizing effect of citrulline dicarboxylic acid, in a preferred embodiment according to the invention, the color-changing agent, preferably the bleaching powder or the bleaching paste, further contains at least one complexing agent selected from the group consisting of ethylenediamine disuccinate (EDDS), glutamic acid-N,N-diacetic acid (GLDA), N,N-bis(carboxymethyl)-L-alanine (MGDA), ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEDTA) and / or their sodium, potassium or ammonium salts.

[0104] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, are characterized in that they further contain at least one complexing agent selected from the group consisting of ethylenediamine disuccinate (EDDS), glutamic acid N,N-diacetic acid (GLDA), N,N-bis(carboxymethyl)-L-alanine (MGDA), ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEDTA) and / or their sodium, potassium or ammonium salts.

[0105] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, are characterized in that the at least one complexing agent, selected from the group consisting of ethylenediamine disuccinate (EDDS), glutamic acid-N,N-diacetic acid (GLDA), N,N-bis(carboxymethyl)-L-alanine (MGDA), ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEDTA) and / or their sodium, potassium or ammonium salts, is contained in a total amount of 0.05 to 10.0 wt.%, preferably 0.1 to 7.5 wt.%, more preferably 0.2 to 4.5 wt.%, even more preferably 0.4 to 2.5 wt.% and most preferably 0.5 to 1.9 wt.%, in each case based on the weight of the color-changing agent.

[0106] According to the invention, preferred color-changing agents, preferably bleaching powders or bleaching pastes, additionally contain at least one inorganic alkalizing agent, solid at 20 °C and 1013 mbar, preferably in a total amount of 1–60 wt.%, more preferably 5–55 wt.%, particularly preferably 10–50 wt.%, and most preferably 15–45 wt.%, in each case based on the weight of the color-changing agent. According to the invention, particularly preferred inorganic alkalizing agents, solid at 20 °C and 1013 mbar, are selected from alkali metal silicates, alkaline earth metal silicates, alkaline earth metal hydroxide carbonates, alkaline earth metal carbonates, alkali metal metasilicates, alkaline earth metal metasilicates, alkali metal hydroxides, alkaline earth metal hydroxides, (earth) alkali metal phosphates, and (earth) alkali metal hydrogen phosphates, as well as mixtures of these substances.Particularly preferred inorganic alkalizing agents according to the invention, which are solid at 20 °C and 1013 mbar, are selected from sodium metasilicates with a molar SiO2 / Na2O ratio of > 2, preferably 2.5 to 3.5, and from magnesium hydroxide carbonates as well as mixtures of these substances. Magnesium hydroxide carbonates preferred according to the invention are those with the formula MgCOs ■ Mg(OH)2 ■ 2 H2O and those with the formula MgCOs ■ Mg(OH)2. Magnesium hydroxide carbonate with the formula MgCOs ■ Mg(OH)2 is particularly preferred according to the invention.

[0107] According to the invention, particularly preferred color-changing agents, preferably bleaching powders or bleaching pastes, contain, based on their total weight, 25-50 wt.%, preferably 30-45 wt.%, particularly preferably 34-40 wt.% sodium silicates with a molar SiO2 / Na2O ratio of > 2, preferably 2.5 to 3.5, and 2-20 wt.%, preferably 5-15 wt.%, particularly preferably 8-25 wt.% magnesium hydroxide carbonate as inorganic alkalizing agents, solid at 20 °C and 1013 mbar.

[0108] According to the invention, exceptionally preferred color-changing agents, preferably bleaching powders or bleaching pastes, contain, based on their total weight, 25-50 wt.%, preferably 30-45 wt.%, particularly preferably 34-40 wt.% sodium silicates with a molar SiO2 / Na2O ratio of > 2, preferably 2.5 to 3.5, and 2-20 wt.%, preferably 5-15 wt.%, particularly preferably 10-13 wt.% magnesium hydroxide carbonate with the formula MgCOs ■ Mg(OH)2 as inorganic alkalizing agents, solid at 20 °C and 1013 mbar.

[0109] For dust removal of the color-changing agents of the invention, which are present as bleaching powder, at least one dust removal agent can be added, which is in particular selected from at least one oil, in particular selected from paraffin oil, silicone oils, branched fatty alcohols or ester oils as well as mixtures of these oils, wherein paraffin oil and branched fatty alcohols are particularly preferred.

[0110] According to the invention, preferred bleaching powders therefore additionally contain at least one oil in a total amount of 0.1–15 wt.%, preferably 0.5–10 wt.%, particularly preferably 1–8 wt.%, and most preferably 2–6 wt.%, in each case based on the weight of the bleaching powder. At least one oil can be added as a carrier medium for color-changing agents according to the invention, which are present as a bleaching paste. This oil is particularly selected from paraffin oil, silicone oils, branched fatty alcohols, or ester oils, as well as mixtures of these oils, with paraffin oil and branched fatty alcohols being particularly preferred.

[0111] According to the invention, preferred bleaching pastes therefore additionally contain at least one oil in a total amount of 16 - 60 wt.%, preferably 20 - 50 wt.%, particularly preferably 25 - 45 wt.%, in each case based on the weight of the bleaching paste.

[0112] According to the invention, preferred oils are selected from natural and synthetic hydrocarbons, particularly preferably from paraffin oils, Ci8-O3o-isoparaffins, in particular isoeicosan, polyisobutene and polydecenes, further selected from Cs-Cie-isoparaffins, in particular from isodecane, isododecane, isotetradecane and isohexadecane and mixtures thereof, as well as 1,3-di-(2-ethylhexyl)-cyclohexane.

[0113] Further oils preferred according to the invention are selected from the benzoic acid esters of linear or branched C8-22 alkanols. Benzoic acid C12-C15 alkyl esters are particularly preferred.

[0114] Further preferred oils according to the invention are selected from fatty alcohols having 6 to 30 carbon atoms, which are unsaturated or branched and saturated or branched and unsaturated. Preferred alcohol oils are 2-hexyldecanol, 2-octyldodecanol, 2-ethylhexyl alcohol, and isostearyl alcohol. 2024P00117WÖ 15

[0115] Further cosmetic oils preferred according to the invention are selected from the triglycerides (= triple esters of glycerol) of linear or branched, saturated or unsaturated, optionally hydroxylated C8-30 fatty acids. The use of natural oils is particularly preferred, e.g., amaranth seed oil, apricot kernel oil, argan oil, avocado oil, babassu oil, cottonseed oil, borage seed oil, camelina oil, safflower oil, peanut oil, pomegranate seed oil, grapefruit seed oil, hemp oil, hazelnut oil, elderberry seed oil, blackcurrant seed oil, jojoba oil, linseed oil, macadamia nut oil, corn germ oil, almond oil, marula oil, evening primrose oil, olive oil, palm oil, palm kernel oil, Brazil nut oil, pecan oil, peach kernel oil, rapeseed oil, castor oil, sea buckthorn pulp oil, sea buckthorn kernel oil, sesame oil, soybean oil, sunflower oil, grapeseed oil, walnut oil, rosehip oil, wheat germ oil, and the liquid components of coconut oil and the like. Synthetic triglyceride oils, especially oapric / oaprylic triglycerides, are also preferred.

[0116] Further cosmetic oils particularly preferred according to the invention are selected from the dicarboxylic acid esters of linear or branched β2-β0-alkanols, in particular diisopropyl adipate, di-n-butyl adipate, di-(2-ethylhexyl) adipate, dioctyl adipate, diethyl 1- / di-n-butyl / dioctyl sebacate, di-isopropyl sebacate, dioctyl malate, dioctyl maleate, dicaprylyl maleate, diisooctyl succinate, di-2-ethylhexyl succinate and di-(2-hexyldecyl) succinate.

[0117] Further cosmetic oils particularly preferred according to the invention are selected from the esters of linear or branched saturated or unsaturated fatty alcohols with 2 - 30 carbon atoms with linear or branched saturated or unsaturated fatty acids with 2 - 30 carbon atoms, which may be hydroxylated. These preferably include 2-hexyldecyl stearate, 2-hexyldecyl laurate, isodecyl neopentanoate, isononyl isononanoate, 2-ethylhexyl palmitate and 2-ethylhexyl stearate, isopropyl myristate, isopropyl palmitate, isopropyl stearate, isopropyl isostearate, isopropyl oleate, isooctyl stearate, isononyl stearate, isocetyl stearate, isononyl isononanoate, isotridecyl isononanoate, cetearyl isononanoate, 2-ethylhexyl laurate, 2-ethylhexyl isostearate, 2-ethylhexyl cocoate, 2-octyldodecyl palmitate, 2-butyloctanoic acid butyloctanoate, diisotridecyl acetate, n-butyl stearate, n-hexyl laurate, n-decyl oleate, oleyl oleate, Oleylerucate, erucyl oleate, erucylerucate, ethylene glycol dioleate and ethylene glycol dipalmitate.Further cosmetic oils preferred according to the invention are selected from the adsorption products of 1 to 5 propylene oxide units to mono- or polyhydric Cs-22 alkanols, such as octanol, decanol, decanediol, lauryl alcohol, myristyl alcohol, and stearyl alcohol, e.g., PPG-2 myristyl ether and PPG-3 myristyl ether. Further cosmetic oils preferred according to the invention are selected from the adsorption products of at least 6 ethylene oxide and / or propylene oxide units to mono- or polyhydric Cs-22 alkanols such as glycerol, butanol, butanediol, myristyl alcohol, and stearyl alcohol, which may optionally be esterified, e.g., PPG-14 butyl ether, PPG-9 butyl ether, PPG-10 butanediol, PPG-15 stearyl ether, and glycereth-7 diisononanoate.

[0118] Further cosmetic oils preferred according to the invention are selected from the O8-O22 fatty alcohol esters of monovalent or polyvalent O2-O7 hydroxycarboxylic acids, in particular the esters of glycolic acid, lactic acid, malic acid, tartaric acid, oetric acid and salicylic acid, e.g. C12-C15 alkyl lactate.

[0119] Further cosmetic oils preferred according to the invention are selected from the symmetrical, 2024P00117WÖ 16 unsymmetrical or cyclic esters of carbonic acid with 03-22-alkanols, 03-22-alkandiols or C3-22-alkanetriols, e.g. dicaprylyl carbonate, or the esters according to DE 19756454 A1, in particular glycerol carbonate.

[0120] Other cosmetic oils suitable according to the invention are selected from the silicone oils, which include, for example, dialkyl and alkylarylsiloxanes such as decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, dimethylpolysiloxane and methylphenylpolysiloxane, but also hexamethyldisiloxane, octamethyltrisiloxane and decamethyltetrasiloxane.

[0121] According to the invention, it may be extremely preferred to use mixtures of the aforementioned oils.

[0122] Preferred color-changing agents according to the invention, preferably bleaching powders or bleaching pastes, are characterized in that the cosmetic oil is selected from natural and synthetic hydrocarbons, particularly preferably from paraffin oils, omega-omeso-isoparaffins, in particular isoeicosan, polyisobutene and polydecenes, Cs-Cie isoparaffins, as well as 1,3-di-(2-ethylhexyl)cyclohexane; the benzoic acid esters of linear or branched omega-22-alkanols; fatty alcohols with 6 to 30 carbon atoms, which are unsaturated or branched and saturated or branched and unsaturated; triglycerides of linear or branched, saturated or unsaturated, optionally hydroxylated Cs-so fatty acids, in particular natural oils; the dicarboxylic acid esters of linear or branched omega-22-coio-alkanols;esters of linear or branched saturated or unsaturated fatty alcohols with 2–30 carbon atoms with linear or branched saturated or unsaturated fatty acids with 2–30 carbon atoms, which may be hydroxylated; the addition products of 1 to 5 propylene oxide units to mono- or polyhydric Cs-22 alkanols; the addition products of at least 6 ethylene oxide and / or propylene oxide units to mono- or polyhydric O3-22 alkanols; the O8-O22 fatty alcohol esters of mono- or polyhydric O2-O7 hydroxycarboxylic acids; the symmetrical, asymmetrical, or cyclic esters of carbonic acid with O3-22 alkanols, O3-22 alkanediols, or O3-22 alcanetrioles; the esters of dimers of unsaturated Ci2-O22 fatty acids (dimer fatty acids) with monovalent linear, branched or cyclic O2-Ci8-alkanols or with polyvalent linear or branched O2-Ce-alkanols;silicone oils and mixtures of the aforementioned substances, preferably in a total amount of 0.1–15 wt.%, preferably 0.5–10 wt.%, particularly preferably 1–8 wt.%, extremely preferably 2–6 wt.%, in each case based on the weight of the bleaching powder, or in a total amount of 16–60 wt.%, preferably 20–50 wt.%, particularly preferably 25–45 wt.%, in each case based on the weight of the bleaching paste.

[0123] Further color-changing agents preferred according to the invention, preferably bleaching powders or bleaching pastes, contain at least one polymer selected from acrylic acid homo- and copolymers, methacrylic acid homo- and copolymers, itaconic acid homo- and copolymers, polysaccharides which may be chemically and / or physically modified, and mixtures of these polymers, wherein one or more of the aforementioned polymers are particularly preferably present in a total amount of 0.1–6 wt.%, preferably 0.5–4 wt.%, and particularly preferably 1–3.5 wt.%. 2024P00117WÖ 17

[0124] %, preferably 2 - 3 wt.%, based on the weight of the color-changing agent.

[0125] Another object of the present invention is a method for lightening keratinous fibers, in particular human hair, in which a color-changing agent (B) according to the invention or preferably according to the invention, preferably a bleaching powder or a bleaching paste, according to one of claims 1-10, is mixed with an oxidation composition which, based on its weight, comprises 50-96 wt.%, preferably 70-93 wt.%, particularly preferably 80-90 wt.%, water and 0.5-20 wt.%.The oxidation composition contains -% hydrogen peroxide and further contains at least one pH unit in such an amount that the oxidation composition has a pH value in the range of 2.5 to 5.5, measured at 20°C. It is applied directly to the keratin-containing fibers, left on the fibers for 5 to 60 minutes, and then the fibers are rinsed with water and optionally washed with a surfactant-containing detergent. The color-changing agent (B) and the oxidation composition (Ox) are preferably mixed together in a weight ratio (B) : (Ox) of 0.2 - 1, particularly preferably 0.3 - 0.8, more preferably 0.4 - 0.7, and most preferably 0.5 - 0.6. The oxidation composition (Ox) used in the brightening process according to the invention essentially contains water and hydrogen peroxide. The concentration of the hydrogen peroxide is determined on the one hand by legal requirements and on the other hand by the desired effect.It amounts to 0.5 - 20 wt.%, preferably 3 - 12 wt.%, particularly preferably 6 - 9 wt.% hydrogen peroxide (calculated as 100% H2O2), in each case based on the weight of the oxidation composition (Ox).

[0126] The oxidation composition (Ox) preferably has an acidic pH value, in particular a pH value in the range of 2.5 to 5.5, measured at 20°C, to stabilize the hydrogen peroxide. Complexing agents, preservatives and / or buffer substances are also preferably included to further stabilize the hydrogen peroxide.

[0127] According to the invention, the color-changing agent (B) is preferably composed such that the mixture with the aforementioned oxidation composition (Ox), i.e. the ready-to-use bleaching agent, has an alkaline pH value, preferably a pH value of 8 to 11.5, particularly preferably a pH value of 8.5 to 11, and most preferably a pH value of 9.0 to 10.5, each measured at 20 °C.

[0128] According to the invention, the oxidation compositions (Ox) used most preferably contain at least one oil and / or at least one fat component with a melting point in the range of 23–110 °C, preferably in a total amount of 0.1–60 wt.%, particularly preferably 0.5–40 wt.%, and most preferably 2–24 wt.%, in each case based on the weight of the oxidation composition (Ox) used most preferably according to the invention. The oils suitable for the oxidation compositions (Ox) used most preferably according to the invention are the same oils disclosed above as suitable dedusting agents for bleaching powders or as carriers for bleaching pastes. 2024P00117WG 18

[0129] In the oxidation compositions (Ox) preferably used according to the invention, the fatty components with a melting point in the range of 23 - 110 °C are selected from linear saturated 1-alkanols with 12 - 30 carbon atoms, preferably in a total amount of 0.1 - 8 wt. %, particularly preferably 3.0 to 6.0 wt. %, in each case based on the weight of the oxidation composition (Ox) used according to the invention.

[0130] Preferably, the at least one linear saturated 1-alkanol with 12-30 carbon atoms is selected from lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, arachidyl alcohol, and behenyl alcohol, as well as from mixtures of these 1-alkanols, particularly preferably from cetyl alcohol, stearyl alcohol, and cetyl alcohol / stearyl alcohol mixtures.

[0131] According to the invention, oxidation compositions (Ox) preferably used further contain, based on their weight, at least one linear saturated 1-alkanol with 12-30 carbon atoms in a total amount of 0.1-8 wt.%, preferably in a total amount of 2-6 wt.%, wherein at least one 1-alkanol selected from cetyl alcohol, stearyl alcohol and cetyl alcohol / stearyl alcohol mixtures is included.

[0132] Further oxidation compositions (Ox) preferably used according to the invention contain at least one fatty component with a melting point in the range of 23 - 110 °C, selected from esters of a saturated, monovalent Cie-Ceo-alkanol and a saturated Cs-Cse monocarboxylic acid, in particular cetyl behenate, stearyl behenate and C2o-C4o alkyl stearate, glycerol triesters of saturated linear C12-Cso-carboxylic acids, which may be hydroxylated, candelilla wax, carnauba wax, beeswax, saturated linear C14-Cse-carboxylic acids and mixtures of the aforementioned substances.

[0133] Further oxidation compositions (Ox) preferably used according to the invention contain at least one surfactant or at least one emulsifier, preferably in a total amount of 0.5 - 10 wt.%, preferably 1 - 5 wt.%, in each case based on the weight of the oxidation composition (Ox) used according to the invention.

[0134] Surfactants and emulsifiers as defined in this application are amphiphilic (bifunctional) compounds consisting of at least one hydrophobic and at least one hydrophilic molecular moiety. The hydrophobic moiety is preferably a hydrocarbon chain with 8-28 carbon atoms, which may be saturated or unsaturated, linear or branched. A linear Cs-C28 alkyl chain is particularly preferred. Key properties of the surfactants and emulsifiers include oriented absorption at interfaces, aggregation into micelles, and the formation of lyotropic phases.

[0135] According to the invention, anionic, nonionic, and cationic surfactants are particularly suitable. However, zwitterionic and amphoteric surfactants are also very suitable according to the invention.

[0136] In the compositions according to the invention, all anionic surfactants suitable for use on the human body are suitable as anionic surfactants. These are characterized by a water-soluble anionic group, such as a carboxylate, sulfate, sulfonate, or phosphate group, and a lipophilic alkyl group with 8 to 30 carbon atoms. Additionally, the molecule may contain glycol or polyglycol ether groups, ester, ether, and amide groups, as well as hydroxyl groups. Examples of suitable anionic surfactants include linear and branched fatty acids with 8 to 30 carbon atoms (soaps), alkyl ether carboxylic acids, acyl sarcosides, acyltaurides, acyl isethionates, sulfosuccinic acid mono-, dialkyl esters and sulfosuccinic acid mono-alkyl polyoxyethyl esters, linear alkanesulfonates, linear alpha-olefin sulfonates, alkyl sulfates and alkyl ether sulfates, as well as alkyl and / or alkenyl phosphates.Preferred anionic surfactants are alkyl sulfates, alkyl ether sulfates, and alkyl ether carboxylic acids, each with 10 to 18 carbon atoms, preferably 12 to 14 carbon atoms in the alkyl group, and up to 12 glycol ether groups, preferably 2 to 6 glycol ether groups in the molecule. Examples of such surfactants are the compounds with the INCI names Sodium Laureth Sulfate, Sodium Lauryl Sulfate, Sodium Myreth Sulfate, or Sodium Laureth Carboxylate.

[0137] Zwitterionic surfactants are surface-active compounds that contain at least one quaternary ammonium group and at least one carboxylate, sulfonate, or sulfate group in their molecule. Particularly suitable zwitterionic surfactants include the so-called betaines, such as N-alkyl-N,N-dimethylammonium glycinates (e.g., cocoalkyl-dimethylammonium glycinate), N-acyl-aminopropyl-N,N-dimethylammonium glycinates (e.g., cocosacylaminopropyl-dimethylammonium glycinate), and 2-alkyl-3-carboxymethyl-3-hydroxyethyl-imidazolines, each with 8 to 18 carbon atoms in the alkyl or acyl group, as well as cocoacylaminoethyl-hydroxyethylcarboxymethyl glycinate. A preferred zwitterionic surfactant is the fatty acid amide derivative known under the INCI name cocamidopropyl betaine.

[0138] Amphoteric surfactants are defined as surface-active compounds that, in addition to a Cs-C24 alkyl or acyl group in the molecule, contain at least one free amino group and at least one -COCH or -SOsH group and are capable of forming internal salts. Examples of suitable amphoteric surfactants include N-alkylglycines, N-alkylpropionic acids, N-alkylaminobutyric acids, N-alkyliminodipropionic acids, N-hydroxyethyl-N-alkylamidopropylglycines, N-alkyltaurines, N-alkylsarcosines, 2-alkylaminopropionic acids, and alkylaminoacetic acids, each with 8 to 24 carbon atoms in the alkyl group. Particularly preferred amphoteric surfactants are N-cocosalkylaminopropionate, cocosacylaminoethylaminopropionate, and Ci2-Ci8-acylsarcosine.

[0139] Non-ionic surfactants contain, as a hydrophilic group, e.g. a polyol group, a polyalkylene glycol ether group or a combination of polyol and polyglycol ether groups. Examples of such compounds include addition products of 4 to 50 mol of ethylene oxide and / or 0 to 5 mol of propylene oxide to linear and branched fatty alcohols, fatty acids and alkylphenols, each with 8 to 20 carbon atoms in the alkyl group; ethoxylated mono-, di- and triglycerides, such as glycerol monolaurate + 20 ethylene oxide and glycerol monostearate + 20 ethylene oxide; sorbitan fatty acid esters and addition products of ethylene oxide to sorbitan fatty acid esters, such as the polysorbates (Tween 20, Tween 21, Tween 60, Tween 61, Tween 81); addition products of ethylene oxide to fatty acid alkanolamides and fatty amines; and alkyl polyglycosides.Suitable nonionic surfactants include C8-C22 alkyl mono- and oligoglycosides and their ethoxylated analogues, as well as ethylene oxide adsorption products to saturated or unsaturated linear fatty alcohols, each containing 2 to 30 moles of ethylene oxide per mole of fatty alcohol. 2024P00117WC 20.

[0140] Further oxidation compositions preferably used according to the invention are characterized in that the at least one anionic surfactant is selected from alkyl sulfates, alkyl ether sulfates and alkyl ether carboxylic acids, each having 10 to 18 C atoms, preferably 12 to 14 C atoms in the alkyl group and up to 12 glycol ether groups, preferably 2 to 6 glycol ether groups, in the molecule.

[0141] Further oxidation compositions preferably used according to the invention are characterized in that they contain at least one non-ionic surfactant selected from ethylene oxide reaction products to saturated or unsaturated linear fatty alcohols, each with 2 to 30 moles of ethylene oxide per mole of fatty alcohol, and at least one anionic surfactant selected from alkyl sulfates, alkyl ether sulfates and alkyl ether carboxylic acids, each with 10 to 18 carbon atoms, preferably 12 to 14 carbon atoms in the alkyl group and up to 12 glycol ether groups, preferably 2 to 6 glycol ether groups, in the molecule, wherein the weight ratio of all anionic surfactants to all non-ionic surfactants is particularly preferably in the range of 5 to 50, preferably 10 to 30.

[0142] In principle, all cationic surfactants suitable for use on the human body are suitable as cationic surfactants in the oxidation compositions (Ox) preferably used according to the invention. These are characterized by at least one water-soluble cationic group, such as a quaternary ammonium group, or by at least one water-soluble, cationizable group, such as an amine group, and furthermore by at least one (lipophilic) alkyl group with 6 to 30 carbon atoms, or at least one (lipophilic) imidazole group, or at least one (lipophilic) imidacylalkyl group. Oxidation compositions (Ox) particularly preferably used according to the invention contain at least one cationic surfactant, preferably selected from quaternary ammonium compounds with at least one C8-C24 alkyl group, ester quats, and amidoamines, each with at least one C8-C24 acyl group, as well as mixtures thereof.Preferred quaternary ammonium compounds with at least one C8-C24 alkyl group are ammonium halides, particularly chlorides, and ammonium alkyl sulfates, such as methosulfates or ethosulfates, like C8-C24 alkyltrimethylammonium chlorides, C8-C24 dialkyldimethylammonium chlorides, and C8-C24 trialkylmethylammonium chlorides, e.g., cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, distearyldimethylammonium chloride, lauryldimethylammonium chloride, lauryldimethylbenzylammonium chloride, and tricetylmethylammonium chloride, as well as the imidazolium compounds known under the INCI names Quaternium-27, Quaternium-83, Quaternium-87, and Quaternium-91. The alkyl chains of the surfactants mentioned above preferably have 8 to 24 carbon atoms.

[0143] Esterquats are cationic surfactants containing at least one ester group, at least one quaternary ammonium group as a structural element, and at least one C8-C24 alkyl or C8-C24 acyl group. Preferred esterquats are quaternary ester salts of fatty acids with triethanolamine, quaternary ester salts of fatty acids with diethanolalkylamines, and quaternary ester salts of fatty acids with 1,2-dihydroxypropyldiethylamines. Such products are marketed, for example, under the trademarks Stepantex®, Dehyquart®, and Armocare®. N,N-Bis(2-palmitoyloxyethyl)dimethylammonium chloride, distearoylethyl dimonium methosulfate, and distearoylethyl hydroxyethylmonium methosulfate are preferred examples of such esterquats.

[0144] Alkylamidoamines are typically prepared by amidation of natural or synthetic C8-C24 fatty acids and fatty acid fractions with di-(C1-C3)alkylaminoamines. A particularly suitable compound from this group of substances according to the invention is stearamidopropyl dimethylamine.

[0145] According to the invention, oxidation compositions (Ox) that are particularly preferably used contain at least one cationic surfactant in a total amount of 0.01 - 5 wt.%, preferably 0.1 - 3 wt.%, particularly preferably 0.3 - 2 wt.%, in each case based on the weight of the oxidation composition (Ox) used according to the invention.

[0146] A further object of the present invention is a multi-component packaging unit (kit-of-parts) for lightening keratinous fibers, which contains at least two separately packaged components and which is characterized in that i) the first component (I) is a color-changing agent according to the invention or a color-changing agent preferred according to the invention, preferably a bleaching powder or a bleaching paste, ii) the second component (II) is an oxidation composition which, based on its weight, contains 50–96 wt.%, preferably 70–93 wt.%, particularly preferably 80–90 wt.%, water and 0.5–20 wt.% hydrogen peroxide and has a pH value in the range of 2.5 to 5.5, measured at 20°C, wherein the components (I) and (II) are preferably in a weight-based ratio (I) : (II) of 0.2–1, particularly preferably 0.3–0.8, more preferably 0.4–0.7, exceptionally preferably 0.5 - 0.6.

[0147] Another object of the present invention is a multi-component packaging unit (kit-of-parts) for color-changing keratinous fibers, in particular human hair, comprising at least three separately packaged components, characterized in that i) the first component (I) is a color-changing agent (B) according to the invention or a color-changing agent preferred according to the invention, preferably a bleaching powder or a bleaching paste, ii) the second component (II) is an oxidation composition comprising, based on its weight, 50–96 wt.%, preferably 70–93 wt.%, particularly preferably 80–90 wt.%, water and 0.5–20 wt.%.-% hydrogen peroxide and has a pH in the range of 2.5 to 5.5, measured at 20°C, iii) the third component (III) is an alkalizing composition (Alk) comprising water and at least one alkalizing agent selected from ammonia, alkanolamines and mixtures thereof, and having a pH in the range of 8 - 12, preferably 9 - 11, particularly preferably 9.5 - 10.5, each measured at 20°C, wherein the color-changing agent (B), the oxidizing composition (Ox) and the 2024P00117WC 22.

[0148] The alkalizing composition (Alk) is preferably in a weight-based ratio (B) : (Ox) : (Alk) of (0.7 - 1 ,3) : (2 - 3) : (2-3), particularly preferably (0.8-1, 2) : (2, 3-2, 7) : (2, 3-2, 7), extremely preferably 1:2:2, to each other.

[0149] A multi-component packaging unit comprises several individual components that are packaged separately from one another, as well as a common package for these components, for example, a folding carton. Within this package, the components are provided separately in different containers. For the purposes of this invention, a container is understood to be an envelope in the form of a bottle, tube, can, pouch, sachet, or similar envelope, which may be resealable. According to the invention, there are no limitations on the material used for the envelope. However, glass or plastic envelopes are preferred.

[0150] In addition, the packaging unit may include application aids such as combs, brushes or paintbrushes, personal protective clothing, especially disposable gloves, and instructions for use.

[0151] In a further preferred embodiment of the invention, a color-changing agent according to the invention, or a preferred one according to the invention, preferably a bleaching powder or a bleaching paste, can be combined with an alkalizing composition and with an oxidizing composition to form a lightening color-changing mixture for keratin fibers. Since the fiber's own pigment melanin is destroyed to a certain degree when keratin fibers, especially hair, are treated with oxidizing agents, particularly hydrogen peroxide, the fibers / hair are inevitably lightened, i.e., they change color even without the presence of a dye. Therefore, the term "color change" within the meaning of the present application includes both lightening and coloring with one or more dyes.

[0152] The alkalizing composition (Alk) used according to the invention contains water and at least one alkalizing agent selected from ammonia, alkanolamines, and mixtures thereof, and has a pH value in the range of 8–12, preferably 9–11, and particularly preferably 9.5–10.5, in each case measured at 20°C. Preferred alkanolamines are selected from monoethanolamine, 2-amino-2-methylpropanol, and triethanolamine, as well as mixtures thereof, with monoethanolamine being particularly preferred. Ammonia is an exceptionally preferred alkalizing agent.

[0153] Ammonia (NH3) is usually used in the form of its aqueous solution. Aqueous ammonia solutions often contain ammonia (NH3) in concentrations of 10 to 32 wt%. The use of an aqueous ammonia solution containing 25 wt% ammonia (NH3) is preferred. In addition to ammonia and alkanolamines, at least one further alkalizing agent may be included, selected from alkali metal silicates, alkaline earth metal silicates, alkaline earth metal hydroxide carbonates, alkaline earth metal carbonates, alkali metal metasilicates, alkaline earth metal metasilicates, alkali metal hydroxides, and alkaline earth metal hydroxides, as well as mixtures of these substances.

[0154] Preferably, ammonia and / or monoethanolamine are contained in the alkalizing compositions preferably used according to the invention (2024P00117WG 23) in amounts of 0.01 - 10 wt.%, preferably 0.1 - 7.5 wt.%, more preferably 0.5 - 5.5 wt.% and particularly preferably 1.5 - 4.5 wt.% - each based on the weight of the alkalizing composition.

[0155] A further object of the present invention is a method for color-changing keratinous fibers, in particular human hair, in which a color-changing agent (B) according to the invention or a preferred color-changing agent according to any one of claims 1-10 comprises an oxidation composition (Ox) which, based on its weight, contains 50-96 wt.%, preferably 70-93 wt.%, particularly preferably 80-90 wt.%, water and 0.5-20 wt.% hydrogen peroxide, and furthermore at least one pH-adjusting agent in such an amount that the oxidation composition has a pH value in the range of 2.5 to 5.5, measured at 20°C, and additionally an alkalizing composition (Alk) which contains water and at least one alkalizing agent selected from ammonia, alkanolamines and mixtures thereof, and has a pH value in the range of 8-12, preferably 9-11, particularly preferably from 9.5 - .

[0156] 10.5, each measured at 20°C, is mixed, immediately afterwards applied to the keratin-containing fibers, left on the fibers for 5 to 60 minutes and then the fibers are rinsed with water and optionally washed with a surfactant-containing cleaning agent, wherein the color-changing agent (B), the oxidation composition (Ox) and the alkalizing composition (Alk) are preferably mixed together in a weight-related ratio (B) : (Ox) : (Alk) of (0.7 - 1.3) : (2 - 3) : (2 - 3), particularly preferably (0.8 - 1.2) : (2.3 - 2.7) : (2.3 - 2.7), extremely preferably 1 :2:2. According to the invention, the color-changing agent (B) is preferably composed such that the mixture with the aforementioned oxidizing composition (Ox) and with the aforementioned alkalizing composition (Alk), i.e. the ready-to-use color-changing mixture, in particular the bleaching agent, has an alkaline pH value, preferably a pH value of 8 to

[0157] 11.5, particularly preferably having a pH value of 8.5 to 11, extraordinarily preferably having a pH value of 9.0 to 10.5, each measured at 20 °C.

[0158] The ready-to-use mixtures of a color-changing agent according to the invention, or a preferred one according to the invention, with one of the aforementioned oxidation compositions (Ox) and optionally with one of the aforementioned alkalizing compositions (Alk), preferably have a viscosity in the range of 15,000 to 100,000 mPas, particularly preferably 20,000 to 85,000 mPas, in each case measured at 20°C using a Brookfield viscometer type DV-II+, spindle 5, at a speed of 4 revolutions / minute. A viscosity in this range allows the ready-to-use agent to be applied easily and, at the same time, has such flow properties that it guarantees a sufficiently long contact time at the point of action on the keratinous fibers.

[0159] In order to facilitate the miscibility of the alkalizing composition used according to the invention with the color-changing agent used according to the invention or preferably according to the invention and the oxidizing composition used according to the invention, as well as to improve the application properties of the resulting application mixture, the alkalizing composition preferably used according to the invention preferably contains, based on its weight, at least one surfactant in a total amount of 0.5 - 10 wt.%, preferably 2 - 8 wt.%.

[0160] The surfactants suitable for the alkalizing compositions (Alk) preferably used according to the invention are selected from the same anionic, cationic, non-ionic, amphoteric and zwitterionic surfactants and emulsifiers disclosed above as surfactants and emulsifiers suitable for the oxidation compositions (Ox) preferably used.

[0161] Alkalizing compositions (Alk) used particularly preferably according to the invention further contain at least one oil and / or at least one fat component with a melting point in the range of 23–110 °C, preferably in a total amount of 0.1–60 wt.%, particularly preferably 0.5–40 wt.%, and most preferably 2–24 wt.%, in each case based on the weight of the alkalizing composition (Alk) preferably used according to the invention. The oils suitable for the alkalizing compositions (Alk) preferably used according to the invention are the same oils disclosed above as suitable dedusting agents for bleaching powders or carriers for bleaching pastes.

[0162] In the alkalizing compositions (Alk) used preferably according to the invention, the fatty components with a melting point in the range of 23 - 110 °o are selected from linear saturated 1-alkanols with 12 - 30 carbon atoms, preferably in a total amount of 0.1 - 20 wt.%, particularly preferably 3 - 15 wt.%, extraordinarily preferably 5 - 10 wt.%, in each case based on the weight of the alkalizing composition used according to the invention.

[0163] Preferably, the at least one linear saturated 1-alkanol with 12-30 carbon atoms is selected from lauryl alcohol, myristyl alcohol, ethyl alcohol, stearyl alcohol, arachidyl alcohol, and behenyl alcohol, as well as from mixtures of these 1-alkanols, particularly preferably from ethyl alcohol, stearyl alcohol, and ethyl alcohol / stearyl alcohol mixtures.

[0164] Alkalizing compositions (Alk) preferably used according to the invention further contain, based on their weight, at least one linear saturated 1-alkanol with 12-30 carbon atoms in a total amount of 0.1-20 wt.%, preferably in a total amount of 3-15 wt.%, most preferably 5-10 wt.%, wherein at least one 1-alkanol selected from ethyl alcohol, stearyl alcohol and ethyl alcohol / stearyl alcohol mixtures is included.Further alkalizing compositions (Alk) preferably used according to the invention contain at least one fatty component with a melting point in the range of 23–110 °C, selected from esters of a saturated monohydric oil-oil alkanol and a saturated oleo-oleic monocarboxylic acid, in particular ethyl behenate, stearyl behenate, and oleo-oleo-alkyl stearate, glycerol triesters of saturated linear C12–O30 carboxylic acids, which may be hydroxylated, almond wax, arnica wax, beeswax, saturated linear C14–O36 carboxylic acids, and mixtures of the aforementioned substances. Furthermore, the color-changing agents according to the invention, or the color-changing compositions preferably used according to the invention, may contain at least one direct dye. These are dyes that adhere directly to the hair and do not require an oxidative process to form the color.To mattify undesirable residual color impressions caused by melanin degradation products, particularly in the reddish or bluish range, certain direct-acting dyes of complementary colors are preferably included. Direct-acting dyes are typically nitrophenylenediamines, nitroaminophenols, azo dyes, anthraquinones, or indophenols. Direct-acting dyes are known as anionic, cationic, and nonionic direct-acting dyes. The direct-acting dyes are preferably used in an amount of 0.001 to 2% by weight, based on the weight of the color-changing agent or alkalizing composition (alcohol).

[0165] Preferred anionic direct dyes are the compounds known under the international names or trade names Acid Yellow 1, Yellow 10, Acid Yellow 23, Acid Yellow 36, Acid Orange 7, Acid Red 33, Acid Red 52, Pigment Red 57:1, Acid Blue 7, Acid Green 50, Acid Violet 43, Acid Black 1, Acid Black 52, Bromophenol Blue and Tetrabromophenol Blue. Preferred cationic direct-drawing dyes are cationic triphenylmethane dyes, for example Basic Blue 7, Basic Blue 26, Basic Violet 2 and Basic Violet 14; aromatic systems substituted with a quaternary nitrogen group, such as Basic Yellow 57, Basic Red 76, Basic Blue 99, Basic Brown 16 and Basic Brown 17; cationic anthraquinone dyes, such as HC Blue 16 (Bluequat B); and direct-drawing dyes containing a heterocycle having at least one quaternary nitrogen atom, in particular Basic Yellow 87, Basic Orange 31 and Basic Red 51.The cationic direct dyes marketed under the trademark Arianor are also preferred cationic direct dyes according to the invention. Nonionic direct dyes particularly suitable are nonionic nitro and quinone dyes and neutral azo dyes. Preferred nonionic direct dyes are those known by the international names or...Handelsnamen HC Yellow 2, HC Yellow 4, HC Yellow 5, HC Yellow 6, HC Yellow 12, HC Orange 1 , Disperse Orange 3, HC Red 1 , HC Red 3, HC Red 10, HC Red 11 , HC Red 13, HC Red BN, HC Blue 2, HC Blue 11 , HC Blue 12, Disperse Blue 3, HC Violet 1 , Disperse Violet 1 , Disperse Violet 4, Disperse Black 9 bekannten Verbindungen, sowie 1 ,4-Diamino-2-nitrobenzol, 2-Amino-4-nitrophenol, 1 ,4-Bis-(2-hydroxyethyl)-amino-2-nitro- benzol, 3-Nitro-4-(2-hydroxyethyl)aminophenol, 2-(2-Hydroxyethyl)amino-4,6-dinitrophenol, 4-[(2- Hydroxyethyl)amino]-3-nitro-1-methylbenzol, 1-Amino-4-(2-hydroxyethyl)amino-5-chlor-2- nitrobenzol, 4-Amino-3-nitrophenol, 1-(2'-Ureidoethyl)amino-4-nitrobenzol, 2-[(4-Amino-2- nitrophenyl)amino]-benzoesäure, 6-N itro-1 ,2,3,4-tetrahydrochinoxalin, 2-Hydroxy-1 ,4-naphtho- chinon, Pikraminsäure und deren Salze, 2-Amino-6-chloro-4-nitrophenol, 4-Ethylamino-3-nitro- benzoesäure und 2-Chlor-6-ethylamino-4-nitrophenol.A combination of tetrabromophenol blue and Acid Red 92 is particularly preferred according to the invention. 2024P00117WG 26.

[0166] As a further optional ingredient, the alkalizing composition preferably used according to the invention contains at least one oxidation dye precursor, which is preferably selected from one or more developer components and optionally one or more coupler components.

[0167] Particularly preferred is at least one oxidation dye precursor in a total amount of 0.0001 to 10.0 wt.%, preferably 0.001 to 8 wt.%, in each case based on the weight of the alkalizing composition preferably used according to the invention.

[0168] According to the invention, it may be preferred to select as the developer component at least one compound from the group consisting of p-phenylenediamine, p-toluenediamine, 2-(2-hydroxyethyl)-p-phenylenediamine, 2-methoxymethyl-p-phenylenediamine, 2-(1,2-dihydroxyethyl)-p-phenylenediamine, N,N-bis-(2-hydroxyethyl)-p-phenylenediamine, N-(4-amino-3-methylphenyl)-N-[3-(1H-imidazol-1-yl)propyl]amine, N,N'-bis-(2-hydroxyethyl)-N,N'-bis-(4-aminophenyl)-1,3-diaminopropan-2-ol, bis-(2-hydroxy-5-aminophenyl)methane, 1,3-bis-(2,5-diaminophenoxy)propan-2-ol, N,N'-Bis-(4-aminophenyl)-1,4-diazacycloheptane, 1,10-Bis-(2,5-diaminophenyl)-1,4,7,10-tetraoxadecane, p-Aminophenol, 4-Amino-3-methylphenol, 4-Amino-2-aminomethylphenol, 4-Amino-2-(1,2-dihydroxyethylphenol, 4-Amino-2-(diethylaminomethyl)phenol, 4,5-Diamino-1-(2-hydroxyethyl)pyrazole, 2,4,5,6-Tetraaminopyrimidine, 4-Hydroxy-2,5,6-triaminopyrimidine, 2-Hydroxy-4,5,6-triaminopyrimidine and their physiologically acceptable salts.

[0169] Preferably, at least one developer component is included in a total amount of 0.0001 to 10.0 wt.%, preferably 0.001 to 8 wt.%, in each case based on the weight of the alkalizing composition preferably used according to the invention.

[0170] Coupler components alone do not produce significant coloration during oxidative staining, but always require the presence of developer components. Therefore, according to the invention, it is preferred that at least one coupler component is also used when at least one developer component is employed.

[0171] Erfindungsgemäß bevorzugte Kupplerkomponenten sind ausgewählt aus 3-Aminophenol, 5-Amino- 2-methylphenol, N-Cyclopentyl-3-aminophenol, 3-Amino-2-chlor-6-methylphenol, 2-Hydroxy-4-ami- nophenoxyethanol, 2,6-Dimethyl-3-aminophenol, 3-T rifluoroacetylamino-2-chlor-6-methylphenol, 5- Amino-4-chlor-2-methylphenol, 5-Amino-4-methoxy-2-methylphenol, 5-(2-Hydroxyethyl)amino-2- methylphenol, 3-(Diethylamino)phenol, N-Cyclopentyl-3-aminophenol, 1 ,3-Dihydroxy-5-(methylami- nojbenzol, 3-Ethylamino-4-methylphenol, 2,4-Dichlor-3-aminophenol, 2-(2,4-Diaminophenoxy)etha- nol, 1 ,3-Bis-(2,4-diaminophenoxy)propan, 1-beta-Hydroxyethyl-3,4-methylendioxyanilin, 1-Methoxy-

[0172] 2-amino-4-(2-hydroxyethylamino)benzol, 1 ,3-Bis-(2,4-diaminophenyl)propan, 2,6-Bis-(2'-hydro- xyethylamino)-1 -methylbenzol, 2-({3-[(2-Hydroxyethyl)amino]-4-methoxy-5-methylphenyl}ami- nojethanol, 2-({3-[(2-Hydroxyethyl)amino]-2-methoxy-5-methylphenyl}amino)ethanol, 2-({3-[(2- Hydroxyethyl)amino]-4,5-dimethylphenyl}amino)ethanol, 2-[3-Morpholin-4-ylphenyl)amino]ethanol,

[0173] 3-Amino-4-(2-methoxyethoxy)-5-methylphenylamin, 1-Amino-3-bis-(2-hydroxyethyl)aminobenzol, Resorcin, Resorcinmonomethylether, 2-Methylresorcin, 5-Methylresorcin, 2,5-Dimethylresorcin, 2- Chlorresorcin, 4-Chlorresorcin, Pyrogallol, 1,2,4-Trihydroxybenzol, 2,6-Dihydroxypyridin, 2-Amino-3- hydroxypy ridin, 2-Amino-5-chlor-3-hydroxypyridin, 3-Amino-2-methylamino-6-methoxypyridin, 2,6- Dihydroxy-3,4-dimethylpyridin, 2,6-Dihydroxy-4-methylpyridin, 2,6-Diaminopyridin, 2,3-Diamino-6- methoxypyridin, 3,5-Diamino-2,6-dimethoxypyridin, 2,6-Dihydroxy-3,4-dimethylpyridin, 3,4- Diaminopyridin, 2-(2-Methoxyethyl)amino-3-amino-6-methoxypyridin, 2-(4’-Methoxyphenyl)amino-3- aminopyridin, 1-Naphthol, 2-Methyl-1-naphthol, 2-Hydroxymethyl-1 -naphthol, 2-Hydroxyethyl-1- naphthol, 1 ,3-Dihydroxynaphthalin, 1 ,5-Dihydroxynaphthalin, 1 ,6-Dihydroxynaphthalin, 1 ,7- Dihydroxynaphthalin, 1 ,8-Dihydroxynaphthalin, 2,7-Dihydroxynaphthalin, 2,3-Dihydroxynaphthalin, 6-Hydroxybenzomorpholin, 4-Hydroxyindol,6-Hydroxyindole, 7-Hydroxyindole, 4-Hydroxyindolin, 6-Hydroxyindolin, 7-Hydroxyindolin, 4,6-Diaminopyrimidine, 4-Amino-2,6-dihydroxypyrimidine, 2,4-Diamino-6-hydroxypyrimidine, 2,4,6-Trihydroxypyrimidine, 2-Amino-4-methylpyrimidine, 2-Amino-4-hydroxy-6-methylpyrimidine and 4,6-Dihydroxy-2-methylpyrimidine or mixtures of these compounds or their physiologically acceptable salts.

[0174] Preferably, at least one coupler component is included in a total amount of 0.0001 to 10.0 wt.%, preferably 0.001 to 8 wt.%, in each case based on the weight of the alkalizing composition preferably used according to the invention.

[0175] Developer components and coupler components are generally used in approximately equimolar amounts to each other. While equimolar use has proven advantageous, a certain excess of individual oxidation dye precursors is not detrimental, so that developer components and coupler components may be present in a molar ratio of 0.2–2, particularly 0.5–1.

[0176] Preferably, the exposure time is 5 to 60 minutes, more preferably 5 to 50 minutes, and most preferably 10 to 45 minutes. During the exposure time of the agents on the fiber, it can be advantageous to support the lightening or color-changing process by applying heat. An exposure phase at room temperature is also according to the invention. In particular, the temperature during the exposure time is between 20 °C and 40 °C, more preferably between 25 °C and 38 °C. The agents already produce good treatment results at physiologically tolerable temperatures below 45 °C.

[0177] After the coloring process is complete, all components on the keratin fibers are rinsed out of the hair with water or a surfactant-containing cleanser. Commercially available shampoo can be used as a cleanser, although it is not necessary to use a cleanser and can be rinsed with tap water if the coloring agent has a higher surfactant content.

[0178] A further object of the present invention is the use of citrulline and at least one dicarboxylic acid having 2 to 10 carbon atoms in a color-changing agent according to any one of claims 1 to 10, which contains at least one persulfate and furthermore 0 to 12 wt.% water, based on the weight of the color-changing agent, for reducing damage to keratinous fibers, in particular human hair, which is caused by treating these fibers with a mixture of the color-changing agent and an oxidation composition which, based on its weight, contains 50 to 96 wt.%, preferably 70 to 93 wt.%, particularly preferably 80 to 90 wt.%, water and 0.5 to 20 wt.% hydrogen peroxide and has a pH value in the range of 2.5 to 5.5, measured at 20°C.

[0179] The statements made regarding the color-changing agents according to the invention and those preferred according to the invention also apply mutatis mutandis to the multi-component packaging units (kits of parts) according to the invention and those preferred according to the invention.

[0180] The statements made regarding the color-changing agents according to the invention and those preferred according to the invention also apply mutatis mutandis to the processes according to the invention and those preferred according to the invention for lightening and / or changing the color of the keratin fibers.

[0181] The statements made regarding the oxidation compositions or alkalizing compositions used according to the invention and preferably according to the invention also apply mutatis mutandis to the multi-component packaging units (kits of parts) according to the invention and preferably according to the invention.

[0182] The statements made regarding the oxidation compositions or alkalizing compositions used according to the invention and preferably according to the invention also apply mutatis mutandis to the processes according to the invention and preferably according to the invention for brightening and / or changing the color of the keratin fibers.

[0183] What has been said about the color-changing agents according to the invention and those preferred according to the invention also applies mutatis mutandis to the use according to the invention.

[0184] What has been said about the oxidation compositions or alkalizing compositions used according to the invention and preferably according to the invention also applies mutatis mutandis to the use according to the invention.

[0185] The following examples are intended to explain the invention in more detail, without limiting it thereto.

[0186] EXAMPLES

[0187] 1.1 Developer emulsion 2024P00117WG 29

[0188] 1.2 Bleaching Powder Formulations

[0189] (Unless otherwise stated, quantities are given in percent by weight)

[0190] The bleaching powders marked (E) are according to the invention. The bleaching powders marked (V) are comparison bleaching powders.

[0191] 2. Application

[0192] The respective bleaching powder and developer emulsion were mixed together in a weight ratio of 1:2.

[0193] 100 g of the freshly prepared mixture of the respective bleaching powder and developer emulsion were applied to dry hair strands (4 g of application mixture per gram of hair).

[0194] After the strands were bleached for 45 minutes at 35°C, they were rinsed with water for 2 minutes and dried with a hairdryer.

[0195] This bleaching process was repeated once, so that the strands were bleached twice in succession.

[0196] Result

[0197] The hair bleached with one of the bleaching powders (E) No. 4 or No. 6 according to the invention felt softer and smoother and showed a shinier, less damaged surface than the hair bleached with one of the comparison bleaching powders No. 1 (V), No. 2 (V), No. 3 (V) or No. 5 (V).

[0198] All bleaching powders achieved an equally good lightening result.

Claims

1. 2024P00117WG 30 Patent claims 1. Agent for oxidative color change, in particular for lightening, of keratinous fibers, especially human hair, containing a) at least one persulfate selected from the group consisting of sodium peroxodisulfate, potassium peroxodisulfate and ammonium peroxodisulfate and mixtures thereof, and b) citrulline and c) at least one dicarboxylic acid having 2 to 10 carbon atoms and d) 0 to 12 wt% water, based on the weight of the color-changing agent.

2. Color-changing agent according to claim 1, characterized in that at least one persulfate selected from the group consisting of sodium peroxodisulfate, potassium peroxodisulfate and ammonium peroxodisulfate and mixtures thereof, is contained in a total amount of 5-85 wt.%, preferably 10-75 wt.%, particularly preferably 15-65 wt.%, extraordinarily preferably 20-55 wt.%, further extraordinarily preferably 25-50 wt.% and particularly 30-45 wt.%, in each case based on the weight of the color-changing agent.

3. Color-changing agent according to claim 1 or 2, characterized in that citrulline is contained in an amount of 0.1 to 2 wt.%, preferably 0.2 to 1 wt.%, particularly preferably 0.4 to 0.8 wt.%, based on the weight of the color-changing agent.

4. Color-changing agent according to any one of claims 1-3, characterized in that the at least one dicarboxylic acid having 2 to 10 carbon atoms is selected from succinic acid, malic acid, oxalic acid, malonic acid, adipic acid, pimelic acid, corticic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, D-tartaric acid, L-tartaric acid, meso-tartaric acid, racemic acid, alpha-ketoglutaric acid, beta-ketoglutaric acid, oxaloacetic acid, and / or at least one salt of these acids as well as mixtures of these acids and / or acid salts, wherein the at least one dicarboxylic acid having 2 to 10 carbon atoms is preferably selected from succinic acid, malic acid and maleic acid as well as their salts, wherein succinic acid and / or at least one salt of succinic acid is particularly preferably included.

5. Color-changing agent according to any one of claims 1-4, characterized in that the at least one dicarboxylic acid with 2 to 10 carbon atoms and / or at least one salt of this acid(s) is contained in a total amount of 0.03-7 wt.%, preferably 0.1-5 wt.%, particularly preferably 0.5-3 wt.%, and most preferably 0.9-1.5 wt.%, based on the weight of the color-changing agent, preferably succinic acid and / or at least one salt of the Succinic acid is contained in a total amount of 0.03 - 7 wt.%, preferably 0.1 - 5 wt.%, particularly preferably 0.5 - 3 wt.%, and extraordinarily preferably 0.9 - 1.5 wt.%, based on the weight of the color-changing agent, as converted to the mass of free dicarboxylic acid.

6. Color-changing agent according to one of claims 1-5, characterized in that it additionally contains arginine or at least one salt of arginine.

7. Color-changing agent according to claim 6, characterized in that arginine or at least one salt of arginine is contained in a total amount, converted to the mass of free amino acid, of 0.1 - 3 wt.%, preferably 0.15 - 2 wt.%, particularly preferably 0.2 - 1.5 wt.%, and most preferably 0.4 - 1.0 wt.%, in each case based on the weight of the color-changing agent.

8. Color-changing agent according to one of claims 1-7, characterized in that it further contains at least one complexing agent selected from the group consisting of ethylenediamine disuccinate (EDDS), glutamic acid N,N-diacetic acid (GLDA), N,N-bis(carboxymethyl)-L-alanine (MGDA), ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEDTA) and / or their physiologically acceptable salts.

9. Color-changing agent according to claim 8, characterized in that the at least one complexing agent selected from the group consisting of ethylenediamine disuccinate (EDDS), glutamic acid N,N-diacetic acid (GLDA), N,N-bis(carboxymethyl)-L-alanine (MGDA), ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEDTA) and / or their sodium, potassium or ammonium salts, is contained in a total amount of 0.05 to 10.0 wt.%, preferably 0.1 to 7.5 wt.%, more preferably 0.2 to 4.5 wt.%, even more preferably 0.4 to 2.5 wt.% and most preferably 0.5 to 1.9 wt.%, in each case based on the weight of the color-changing agent.

10. Color-changing agent according to any one of claims 1-9, characterized in that it additionally contains at least one inorganic alkalizing agent, solid at 20 °C and 1013 mbar, preferably in a total amount of 1-60 wt.%, preferably 5-55 wt.%, particularly preferably 10-50 wt.%, and most preferably 15-45 wt.%, in each case based on the weight of the color-changing agent.

11. A method for lightening keratinous fibers, in particular human hair, characterized in that a color-changing agent (B) according to one of claims 1-10 is mixed with an oxidation composition which, based on its weight, comprises 50-96 wt.%, preferably 70-93 wt.%, particularly preferably 80-90 wt.%, The composition contains water and 0.5–20 wt% hydrogen peroxide and further contains at least one pH adjuster in such an amount that the oxidation composition has a pH value in the range of 2.5 to 5.5, measured at 20°C, is applied immediately thereafter to the keratin-containing fibers, left on the fibers for 5 to 60 minutes, and the fibers are then rinsed with water and optionally washed with a surfactant-containing detergent, wherein the color-changing agent (B) and the oxidation composition (Ox) are preferably mixed together in a weight ratio (B) : (Ox) of 0.2–1, particularly preferably 0.3–0.8, more preferably 0.4–0.7, and most preferably 0.5–0.

6.

12. Multi-component packaging unit (kit-of-parts) for lightening keratinous fibers, in particular human hair, comprising at least two separately packaged components, characterized in that i) the first component (I) is a color-changing agent according to any one of claims 1-10, ii) the second component (II) is an oxidation composition which, based on its weight, contains 50-96 wt.%, preferably 70-93 wt.%, particularly preferably 80-90 wt.%, water and 0.5-20 wt.% hydrogen peroxide and has a pH value in the range of 2.5 to 5.5, measured at 20°C, wherein the components (I) and (II) are preferably in a weight ratio (I) : (II) of 0.2-1, particularly preferably 0.3-0.8, further preferably 0.4-0.7, and most preferably 0.5-0.

6. are in relation to each other.

13. Method for changing the color of keratinous fibers, in particular human hair, in which a color-changing agent (B) according to one of claims 1-10 is combined with an oxidation composition (Ox) comprising, based on their weight, 50-96 wt.%, preferably 70-93 wt.%, particularly preferably 80-90 wt.%, water and 0.5-20 wt.%.- % hydrogen peroxide and furthermore contains at least one pH adjusting agent in such an amount that the oxidation composition has a pH value in the range of 2.5 to 5.5, measured at 20°C, and is additionally mixed with an alkalizing composition (Alk) which contains water and at least one alkalizing agent selected from ammonia, alkanolamines and mixtures thereof and has a pH value in the range of 8 - 12, preferably 9 - 11, particularly preferably 9.5 - 10.5, each measured at 20°C, is immediately applied to the keratin-containing fibers, left on the fibers for 5 to 60 minutes and the fibers are then rinsed with water and optionally washed with a surfactant-containing detergent, wherein the color-changing agent (B), the oxidation composition (Ox) and the. Alkalizing composition (Alk) preferably in a weight-based ratio (B) : (Ox) : (Alk) of (0.7 - 1 ,3) : (2 - 3) : (2 - 3), particularly preferably (0.8 - 1 ,2) : (2.3 - 2.7) : (2.3 - 2.7), extremely preferably 1:2:2, are mixed together.

14. Multi-component packaging unit (kit-of-parts) for color-changing keratinous fibers, in particular human hair, comprising at least three separately packaged components, characterized in that i) the first component (I) is a color-changing agent (B) according to any one of claims 1-10, ii) the second component (II) is an oxidation composition comprising, based on its weight, 50-96 wt.%, preferably 70-93 wt.%, particularly preferably 80-90 wt.% water and 0.5-20 wt.%iii) the third component (III) is an alkalizing composition (Alk) comprising water and at least one alkalizing agent selected from ammonia, alkanolamines and mixtures thereof, and having a pH in the range of 8 to 12, preferably 9 to 11, particularly preferably 9.5 to 10.5, each measured at 20°C, wherein the color-changing agent (B), the oxidizing composition (Ox) and the alkalizing composition (Alk) are preferably in a weight ratio (B) : (Ox) : (Alk) of (0.7 - 1.3) : (2 - 3) : (2 - 3), particularly preferably (0.8 - 1.2) : (2.3 - 2.7) : (2.3 - 2.7), exceptionally preferred 1:2:2, to each other.

15. Use of citrulline and at least one dicarboxylic acid having 2 to 10 carbon atoms in a color-changing agent, which contains at least one persulfate and furthermore 0 to 12 wt.% water, based on the weight of the color-changing agent, for reducing damage to keratinous fibers, in particular human hair, caused by treating these fibers with a mixture of the color-changing agent and an oxidizing composition, which, based on its weight, contains 50–96 wt.%, preferably 70–93 wt.%, particularly preferably 80–90 wt.% water and 0.5–20 wt.% hydrogen peroxide and has a pH in the range of 2.5 to 5.5, measured at 20°C, wherein said color-changing agent is preferably a color-changing agent according to any one of claims 2–10.

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