A method for treating keratin fibers, comprising the application of a reductive pretreatment agent and the application of a post-treatment agent containing silane

Abstract

The present invention relates to a method for treating keratin fibers, in particular human hair, comprising the following steps: - Application of a pretreatment agent (V) to the keratin fibers, wherein the pretreatment agent contains (V-1) at least one reducing agent selected from the group consisting of dithioerythritol, dithiothreitol, acetylcysteine, dimercaptosuccinic acid, thioglycerol, thiolactic acid, sodium dithionite, zinc dithionite, potassium dithionite, formamidine sulfinic acid, 2-hydroxy-2-sulfinoacetic acid and salts thereof, and - Application of a post-treatment agent (N) to the keratin fibers, wherein the post-treatment agent (N) contains (N-1) at least one organic silicon compound from the group of silanes with one, two or three silicon atoms.

Description

[0001] The present application relates to a method for treating keratin fibers, in particular human hair, which comprises the application of a reductive pretreatment agent (V) and the application of a posttreatment agent (N). The pretreatment agent (V) is characterized by its content of at least one reducing agent from the group consisting of dithioerythritol, dithiothreitol, acetylcysteine, dimercaptosuccinic acid, thioglycerol, thiolactic acid, sodium dithionite, zinc dithionite, potassium dithionite, formamidine sulfinic acid, 2-hydroxy-2-sulfinoacetic acid, and salts thereof. The posttreatment agent (N) contains at least one organic silicon compound from the group of silanes having one, two, or three silicon atoms.

[0002] A second subject matter of the present application is a multi-component packaging unit (kit-of-parts) for treating keratin fibers, which comprises the previously described pretreatment agent (V) and the post-treatment agent (N) separately packaged in two different containers.

[0003] Altering the shape and color of keratin fibers, especially hair, represents an important area of ​​modern cosmetics. Depending on the coloring requirements, hair coloring experts are familiar with various coloring systems. For permanent, intense colorings with good fastness properties and good gray coverage, oxidation dyes are typically used. Such dyes typically contain oxidation dye precursors, so-called developer components, and coupler components, which, under the influence of oxidizing agents such as hydrogen peroxide, form the actual dyes. Oxidation dyes are characterized by very long-lasting coloring results.

[0004] When using direct dyes, the fully formed pigments diffuse from the dyeing agent into the hair fiber. Compared to oxidative hair coloring, the colors obtained with direct dyes are less durable and wash out more quickly. Colorations with direct dyes typically remain on the hair for between 5 and 20 washes.

[0005] The use of color pigments is known for temporary color changes on hair and / or skin. Color pigments are generally understood to be insoluble, color-imparting substances. These are present undissolved in the form of small particles in the coloring formulation and are deposited only externally on the hair fibers and / or the skin surface. Therefore, they can usually be removed without residue after several washes with surfactant-containing cleansers. Various products of this type are available on the market under the name hair mascara.

[0006] Coloring with pigments offers several significant advantages. Because the pigments only attach to the keratin fibers, especially the hair fibers, from the outside, unwanted coloring can be removed quickly and easily without leaving any residue, thus offering the user the opportunity to return to their original hair color immediately and without much effort. This coloring process is therefore particularly attractive for consumers who do not want to recolor their hair regularly.

[0007] Despite these many advantages, the pigment-based coloring system still has some disadvantages, which are due to the pigments' limited penetration into the keratin material. Since the pigments do not diffuse into the keratin fibers, but rather merely deposit themselves on the outer surface of the fiber in the form of a shell or film, the washfastness of the colorations produced with this system still requires improvement. Various studies have attempted to bond the pigment(s) more permanently to the hair surface using film-forming materials, usually polymers.

[0008] The coloring processes of EP 2168633 B1 utilize organosilicon compounds from the silane group, the molecular structure of which includes at least one hydroxyl group and / or hydrolyzable group. Due to the presence of the hydroxyl groups or hydrolyzable groups, the silanes are reactive substances that hydrolyze, oligomerize, or polymerize in the presence of water. The oligomerization or polymerization of the silanes, initiated by the presence of water, ultimately leads, when applied to the keratin material, to the formation of a film that fixes the color-imparting compounds, thus producing very long-lasting colorations.

[0009] However, a closer examination of the dyeing processes disclosed in EP 2168633 B1 revealed that the dyes produced on hair using these agents or processes still require improvement. In particular, the color intensity and abrasion resistance of the dyes from the hair still need to be optimized, and the durability, especially the washfastness of these dyes, also requires further improvement.

[0010] Various studies have already been conducted to improve the washfastness of dyes produced with silanes and pigments, including the effects of various pretreatment agents. For example, WO 2022 / 184357 A1 attempted to improve washfastness by pretreating with an enzyme from the lipase group, and WO 2022 / 184337 A1 used a pretreatment agent containing hydrogen peroxide.

[0011] However, further work on WO 2022 / 184337 A1 revealed that the oxidative pretreatment, which was performed here with an aqueous hydrogen peroxide solution, also resulted in hair lightening and damage. This can be particularly disadvantageous if the user resorts to pigment-based colorants because they want to avoid hair lightening and damage.

[0012] Another disadvantage remains that the films formed from the silanes adhere to different hair types and to different degrees of damage. It has been found that the silane films generally adhere better to damaged hair than to hair with lesser degrees of damage. When coloring the entire head, this results in the colored film peeling off relatively quickly at the roots, whereas the color remains visible much longer in the more damaged areas of the ends. Even though longer-lasting films are desirable in principle, the varying degrees of peeling off at the roots and tips lead to a very uneven or patchy color result, which the user dislikes.

[0013] The object of the present application was to find a method for treating, in particular for coloring, keratin fibers such as hair, with which the films formed from silanes are to be bonded very permanently and evenly to the keratin fibers. The colorants based on silanes and pigments should deliver high color intensities and possess very good fastness properties, in particular, washfastness should be outstanding. Furthermore, a uniform and long-lasting color should be achieved both at the roots and in the hair tips, and the hair should be lightened as little as possible by the coloring process. Furthermore, a uniform color result should be achieved over the entire length of the keratin fiber, regardless of the degree of damage to the keratin fiber, and the silane film should remain as evenly as possible on the fibers over multiple hair washes, even on hair sections with varying degrees of damage.

[0014] Surprisingly, it has now been found that the above-mentioned object can be excellently achieved if keratinic fibers, in particular human hair, are dyed using a process in which a reductive pretreatment agent (V) is first applied to the keratinic fibers and the formation of the silane-based film is only subsequently carried out by applying a post-treatment agent (N).

[0015] By using both agents (V) and (N) in a single dyeing process, keratin fibers could be dyed with particularly high color intensity and high fastness. The reductive pretreatment (V) of the keratin fibers also achieved a surprisingly even and long-lasting lift of the color-imparting compound.

[0016] A first object of the present invention is a method for treating keratin fibers, in particular human hair, comprising the following steps: - Application of a pretreatment agent (V) to the keratin fibers, wherein the pretreatment agent contains (V-1) at least one reducing agent selected from the group consisting of dithioerythritol, dithiothreitol, acetylcysteine, dimercaptosuccinic acid, thioglycerol, thiolactic acid, sodium dithionite, zinc dithionite, potassium dithionite, formamidine sulfinic acid, 2-hydroxy-2-sulfinoacetic acid and salts thereof, and - Application of a post-treatment agent (N) to the keratin fibers, wherein the post-treatment agent (N) contains (N-1) at least one organic silicon compound from the group of silanes with one, two or three silicon atoms.

[0017] In the work leading to this invention, it has been shown that the preferably successive application of agents (V) and (N) enables the creation of very stable and washfast films on the keratin fibers. The use of the organic silanes in agent (N) leads to the formation of a particularly resistant film on the keratin fibers. By using at least one colorant compound from the group of pigments and / or direct dyes in agent (N), the particularly stable films obtained in this way can be colored. The colorant compounds can be permanently fixed to the keratin material in this way, so that extremely washfast colorations with good resistance to abrasion and / or shampooing could be achieved. Keratin material

[0018] Keratin fibers include hair, but also wool and fur. Human hair is particularly preferred as keratin fibers. Pretreatment agent (V)

[0019] The pretreatment agent (V) used in the process according to the invention contains at least one reducing agent (V-1) selected from the group consisting of dithioerythritol, dithiothreitol, acetylcysteine, dimercaptosuccinic acid, thioglycerol, thiolactic acid, sodium dithionite, zinc dithionite, potassium dithionite, formamidine sulfinic acid, 2-hydroxy-2-sulfinoacetic acid and the salts of the aforementioned compounds.

[0020] With the help of the pretreatment agent, the adhesion and thus the durability of the films produced on the keratin material could be significantly increased. In this context, it is assumed that the pretreatment agent (V) hydrophilizes the surface of the keratin material and creates additional reactive sites on the surface of the keratin material. It has been found that this surface modification was particularly effective with the reducing agents dithioerythritol, dithiothreitol, acetylcysteine, dimercaptosuccinic acid, thioglycerol, thiolactic acid, sodium dithionite, zinc dithionite, potassium dithionite, formamidine sulfinic acid, 2-hydroxy-2-sulfinoacetic acid, or the salts of these compounds.

[0021] Dithioerythritol is also known as 1,4-dithioerythritol, erythro-1,4-dimercapto-2,3-butanediol, (2R,3S)-1,4-bis(sulfanyl)butane-2,3-diol, or (2R*,3S*)-1,4-bis(sulfanyl)butane-2,3-diol and has the CAS numbers 6892-68-8 (dithioerythritol) and 7634-42-6 (1,4-dimercapto-2,3-butanediol, unspecified). With dithioerythritol, a particularly uniform color result was observed after repeated shampooing on hair strands with varying degrees of damage. The wash fastness could also be significantly improved when dithioerythritol was used as a reducing agent, therefore the use of dithioerythritol in the pretreatment agent (V) is most preferred.

[0022] Dithiothreitol is formally derived from the sugar alcohol threitol, which belongs to the threose structural type. It occurs in two stereoisomers. The (2S,3S) form is derived from D-threose, the (2R,3R) form from L-threose. Both stereoisomeric forms, as well as a mixture of the two forms, are within the scope of the invention. Dithiothreitol is also alternatively known as 1,4-dimercapto-2,3-butanediol, butane-2,3-diol-1,4-dithiol, and has the CAS numbers 3483-12-3 (DL-threo), 16096-97-2 (L-threo), and 7634-42-6 (unspecified). Very fast colorings have also been achieved with dithiothreitol, which wash out particularly evenly from hair strands. Therefore, the use of dithiothreitol in the pretreatment agent (V) is explicitly preferred.

[0023] Acetylcysteine ​​can also be abbreviated as ACC and has the alternative name mercapturic acid, L-α-acetamido-β-mercaptopropionic acid, (R)-2-acetylamino-3-sulfanylpropanoic acid, or N-acetylcysteine, and has the CAS number 616-91-1. The carboxyl group of acetylcysteine ​​can also be deprotonated and neutralized by a corresponding equivalent of a cationic counterion. Suitable salts of acetylcysteine ​​include the sodium salt, the potassium salt, the ammonium salt, the magnesium salt, and the calcium salt. Very good results have been achieved with acetylcysteine. The use of acetylcysteine ​​and / or its salts in the pretreatment agent (V) is therefore also particularly preferred.

[0024] Dimercaptosuccinic acid, or dimercapto succinic acid, is an organic acid that has two stereocenters substituted by the same residues. Three stereoisomers of dimercaptosuccinic acid exist, all of which are within the scope of the invention. (2R,3R)-2,3-Dimercaptosuccinic acid has the CAS number 10008-75-0. (2S,3R)-2,3-Dimercaptosuccinic acid is also known as meso-2,3-Dimercaptosuccinic acid and has the CAS number 304-55-2. (2S,3S)-2,3-Dimercaptosuccinic acid has the CAS number 27887-82-7. 2418-14-6 is the CAS number of unspecified dimercaptosuccinic acid. One or both of the carboxyl groups present in dimercaptosuccinic acid can also be deprotonated and neutralized by a corresponding equivalent of a cationic counterion. Suitable salts of dimercaptosuccinic acid include the sodium salt, the potassium salt, the ammonium salt, the magnesium salt, and the calcium salt.

[0025] Thioglycerol is glycerol in which one of the three hydroxyl groups has been replaced by a thiol group. Thioglycerol is also alternatively referred to as 1-thioglycerol or 3-mercaptopropane-1,2-diol and has the CAS number 96-27-5. The use of thioglycerol in the pretreatment agent (V) is also preferred.

[0026] Another suitable reducing agent for the pretreatment agent (V) is thiolactic acid, alternatively referred to as 2-mercaptopropionic acid. 2-mercaptopropionic acid is chiral, so the substance comprises the two enantiomers (R)-thiolactic acid and (S)-thiolactic acid. Both enantiomers, as well as their mixture, are within the scope of the invention. When thiolactic acid is referred to without further reference symbols, a 1:1 mixture of (R)-thiolactic acid and (S)-thiolactic acid is meant. Thiolactic acid has the CAS number 79-42-5. The carboxyl group of thiolactic acid can also be deprotonated and neutralized by a corresponding equivalent of a cationic counterion. Suitable salts of thiolactic acid include, for example, the sodium salt, the potassium salt, the ammonium salt, the magnesium salt, and the calcium salt.

[0027] Sodium dithionite is an inorganic reducing agent with the molecular formula Na 2 S 2 O 4and CAS No. 7775-14-6.

[0028] Zinc dithionite is an inorganic reducing agent with the molecular formula ZnS 2 O 4 and CAS No. 7779-86-4.

[0029] Potassium dithionite is an inorganic reducing agent with the molecular formula K 2 S 2 O 4 and CAS No. 14293-73-3.

[0030] Formamidine sulfinic acid is also known as thiourea dioxide or aminoiminomethanesulfinic acid. Formamidine sulfinic acid has the structure of formula (Red-I), but can also exist in the form of its tautomers. Formamidine sulfinic acid has the CAS number 1758-73-2. Formamidine sulfinic acid can also be used in the form of its salts. Suitable examples include the sodium, potassium, and ammonium salts of formamidine sulfinic acid.

[0031] The above-mentioned compounds are commercially available from various chemical suppliers such as Fluka, Merck or Aldrich.

[0032] 2-Hydroxy-2-sulfinoacetic acid is preferably used in the form of its salt, particularly the sodium salt. The compound is commercially available, for example, under the trade name Brüggolit FF7 from Brüggemann.

[0033] The pretreatment agent (V) preferably contains the reducing agent(s) in an amount of 0.1 to 15.0 wt. %, preferably 0.2 to 10.0 wt. %, more preferably 0.3 to 7.5 wt. %, and most preferably 0.5 to 5.5 wt. %. The amounts stated here refer to the total amounts of reducing agents according to the invention, which are related to the total amount of the pretreatment agent (V).

[0034] The pretreatment agent (V) particularly preferably contains - based on the total weight of the pretreatment agent (V) - one or more reducing agents (V-1) in a total amount of 0.1 to 15.0 wt.%, preferably 0.2 to 10.0 wt.%, more preferably 0.3 to 7.5 wt.% and very particularly preferably 0.5 to 5.5 wt.%.

[0035] The pretreatment agent (V) very particularly preferably contains - based on the total weight of the pretreatment agent (V) - one or more reducing agents (V-1) from the group consisting of dithioerythritol, dithiothreitol, acetylcysteine ​​and / or their salts, particularly preferably dithioerythritol and / or dithiothreitol, in a total amount of 0.1 to 15.0 wt.%, preferably 0.2 to 10.5 wt.%, more preferably from 0.3 to 7.5 wt.% and very particularly preferably from 0.5 to 5.5 wt.%.

[0036] In a further very particularly preferred embodiment, a process according to the invention is characterized in that the pretreatment agent (V) - based on the total weight of the pretreatment agent (V) - contains one or more reducing agents (V-1), preferably dithioerythritol, dithiothreitol, acetylcysteine ​​and / or their salts, particularly preferably dithioerythritol and / or dithiothreitol, in a total amount of 0.1 to 15.0 wt.%, preferably 0.2 to 10.5 wt.%, more preferably from 0.3 to 7.5 wt.% and very particularly preferably from 0.5 to 5.5 wt.%. pH value of the pretreatment agent

[0037] The pretreatment agent (V) preferably contains the reducing agent(s) in a cosmetic carrier, which is particularly preferably aqueous or water-containing.

[0038] It has been found that the surface modification of keratin fibers works particularly well when the reducing agent(s) act on the keratin fibers in an alkaline environment. Particularly suitable pH values ​​are in the range of 7.0 to 12.0, preferably 7.5 to 11.5, more preferably 8.0 to 11.0, and especially preferably 8.5 to 10.5.

[0039] In a further very particularly preferred embodiment, a process according to the invention is characterized in that the pretreatment agent (V) contains water and has a pH of 7.0 to 12.0, preferably 7.5 to 11.5, more preferably 8.0 to 11.0 and particularly preferably 8.5 to 10.5.

[0040] To adjust the desired pH, the pretreatment agents (V) may therefore also contain at least one alkalizing agent. The pH values ​​within the meaning of the present invention are pH values ​​measured at a temperature of 22°C.

[0041] As alkalizing agents, the pretreatment agent (V) may contain, for example, ammonia, alkanolamines and / or basic amino acids.

[0042] The alkanolamines which can be used in the agent are preferably selected from primary amines having a C 2 -C 6-Alkyl parent structure which carries at least one hydroxyl group. Preferred alkanolamines are selected from the group consisting of 2-aminoethanol-1-ol (monoethanolamine), 3-aminopropan-1-ol, 4-aminobutan-1-ol, 5-aminopentan-1-ol, 1-aminopropan-2-ol, 1-aminobutan-2-ol, 1-aminopentan-2-ol, 1-aminopentan-3-ol, 1-aminopentan-4-ol, 3-amino-2-methylpropan-1-ol, 1-amino-2-methylpropan-2-ol, 3-aminopropan-1,2-diol, and 2-amino-2-methylpropan-1,3-diol.

[0043] Particularly preferred alkanolamines are selected from 2-aminoethane-1-ol and / or 2-amino-2-methylpropane-1-ol. A particularly preferred embodiment is therefore characterized in that the agent contains an alkanolamine selected from 2-aminoethane-1-ol and / or 2-amino-2-methylpropane-1-ol as an alkalizing agent.

[0044] An amino acid within the meaning of the invention is an organic compound which has in its structure at least one protonatable amino group and at least one -COOH- or -SO 3 H group. Preferred amino acids are aminocarboxylic acids, especially α-(alpha)-aminocarboxylic acids and ω-aminocarboxylic acids, with α-aminocarboxylic acids being particularly preferred.

[0045] Basic amino acids are those amino acids which have an isoelectric point pl of greater than 7.

[0046] Basic α-aminocarboxylic acids contain at least one asymmetric carbon atom. Within the scope of the present invention, both possible enantiomers can be used equally as specific compounds or as mixtures thereof, particularly as racemates. However, it is particularly advantageous to use the naturally occurring isomer form, usually in the L-configuration.

[0047] The basic amino acids are preferably selected from the group consisting of arginine, lysine, ornithine, and histidine, particularly preferably arginine and lysine. In another particularly preferred embodiment, an agent is characterized in that the alkalizing agent is a basic amino acid from the group consisting of arginine, lysine, ornithine, and / or histidine.

[0048] In addition, the agent may contain other alkalizing agents, particularly inorganic alkalizing agents. Inorganic alkalizing agents usable according to the invention are preferably selected from the group consisting of sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, sodium phosphate, potassium phosphate, sodium silicate, sodium metasilicate, potassium silicate, sodium carbonate, and potassium carbonate.

[0049] Very particularly preferred alkalizing agents are ammonia, 2-aminoethan-1-ol (monoethanolamine), 3-aminopropan-1-ol, 4-aminobutan-1-ol, 5-aminopentan-1-ol, 1-aminopropan-2-ol, 1-aminobutan-2-ol, 1-aminopentan-2-ol, 1-aminopentan-3-ol, 1-aminopentan-4-ol, 3-amino-2-methylpropan-1-ol, 1-amino-2-methylpropan-2-ol, 3-aminopropan-1,2-diol, 2-amino-2-methylpropan-1,3-diol, arginine, lysine, ornithine, histidine, sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, sodium phosphate, potassium phosphate, sodium silicate, sodium metasilicate, potassium silicate, sodium carbonate and potassium carbonate.

[0050] Although the pretreatment agents (V) are preferably adjusted to pH values ​​in the alkaline range, it may still be necessary in principle to use small amounts of acidifying agents to fine-tune the desired pH value. Suitable acidifying agents according to the invention include, for example, citric acid, lactic acid, acetic acid, or diluted mineral acids (such as hydrochloric acid, sulfuric acid, phosphoric acid). Aftertreatment agent (N)

[0051] Following the keratin fibers thus prepared, the post-treatment agent (N) is now applied to the keratin fibers within the scope of the method according to the invention.

[0052] The aftertreatment agent (N) is characterized in that it contains at least one organic silicon compound (N-1) from the group of silanes with one, two or three silicon atoms.

[0053] According to IUPAC rules, the term silane refers to a group of chemical compounds based on a silicon backbone and hydrogen. In organic silanes, the hydrogen atoms are completely or partially replaced by organic groups such as (substituted) alkyl groups and / or alkoxy groups. In organic silanes, some of the hydrogen atoms can also be replaced by hydroxy groups.

[0054] Particularly suitable silanes (N-1) are the silanes of formula (I) R 1 R 2 NL-Si(OR 3 ) a (R 4 ) b (I), stand - R 1 , R 2 independently represent a hydrogen atom or a C 1 -C 6 -alkyl group, - L for a linear or branched, divalent C 1 -C 20 -alkylene group, - R 3 for a hydrogen atom or for a C 1 -C6 -alkyl group, - R 4 for a C 1 -C 6 -alkyl group, - a, for an integer from 1 to 3, and - b for the integer 3 - a, and / or their hydrolysis and / or condensation products.

[0055] In a further particularly preferred embodiment, a process according to the invention is characterized in that the aftertreatment agent (N) contains at least one silane (N-1) of the formula (I) and / or its hydrolysis and / or condensation products R 1 R 2 NL-Si(OR 3 ) a (R 4 ) b (I), where - R 1 , R 2 independently represent a hydrogen atom or a C 1 -C 6 -alkyl group, - L for a linear or branched, divalent C 1 -C 20 -alkylene group, - R 3 , R 4independently of each other for a C 1 -C 6 -alkyl group, - a, stands for an integer from 1 to 3, and - b stands for the integer 3 - a.

[0056] The substituents R 1 , R 2 , R 3 , R 4 and L in the compounds of formula (I) and (II) are exemplified below: Examples of a C 1 -C 6 Alkyl groups include methyl, ethyl, propyl, isopropyl, n-butyl, s-butyl, t-butyl, n-pentyl, and n-hexyl. Propyl, ethyl, and methyl are preferred alkyl radicals. Examples of a C 2 -C 6 -Alkenyl group are vinyl, allyl, but-2-enyl, but-3-enyl and isobutenyl, preferred C 2 -C 6 -Alkenyl radicals are vinyl and allyl. Examples of a linear divalent C 1 -C 20 -Alkylene group are, for example, the methylene group (-CH 2 -), the ethylene group (-CH2 -CH 2 -), the propylene group (-CH 2 -CH 2 -CH 2 -) and the butylene group (-CH 2 -CH 2 -CH 2 -CH 2 -). The propylene group (-CH 2 -CH 2 -CH 2 -) is particularly preferred. From a chain length of 3 C atoms, divalent alkylene groups can also be branched. Examples of branched, divalent C 3 -C 20 -Alkylene groups are (-CH 2 -CH(CH 3 )-) and (-CH 2 -CH(CH 3 )-CH 2 -).

[0057] In the organic silicon compounds of formula (I) R 1 R 2 NL-Si(OR 3 ) a (R 4 ) b (I), the residues R 1 and R 2 independently represent a hydrogen atom or a C 1 -C 6 -alkyl group. The radicals R 1 and R 2both represent a hydrogen atom.

[0058] In the middle part of the organic silicon compound is the structural unit or linker -L- which stands for a linear or branched, divalent C 1 -C 20 -alkylene group.

[0059] A divalent C 1 -C 20 -Alkylene group can alternatively be represented as a divalent or divalent C 1 -C 20 -alkylene group, which means that each group L can form two bonds. One bond is formed by the amino group R 1 R 2 N to the linker L, and the second bond is between the linker L and the silicon atom.

[0060] Preferably, -L- represents a linear, bivalent (i.e. divalent) C 1 -C 20 -alkylene group. More preferably, -L- represents a linear divalent C 1 -C 6 -alkylene group. Particularly preferably, -L- represents a methylene group (-CH2 -), an ethylene group (-CH 2 -CH 2 -), a propylene group (-CH 2 -CH 2 -CH 2 -) or a butylene group (-CH 2 -CH 2 -CH 2 -CH 2 -). Most preferably, L represents a propylene group (-CH 2 -CH 2 -CH 2 -).

[0061] The linear propylene group (-CH 2 -CH 2 -CH 2 -) can alternatively be referred to as propane-1,3-diyl group.

[0062] The organic silicon compounds of formula (I) R 1 R 2 NL-Si(OR 3 ) a (R 4 ) b (I), each carry the silicon-containing group -Si(OR 3 ) a (R 4 ) b .

[0063] In the terminal structural unit -Si(OR 3 ) a (R 4 ) b the remainder R 3for a hydrogen atom or a C 1 -C 6 -alkyl group, and the residue R 4 stands for a C 1 -C 6 -alkyl group. R 3 and R 4 independently represent a methyl group or an ethyl group.

[0064] Here, a represents an integer from 1 to 3, and b represents the integer 3 - a. If a represents the number 3, then b is 0. If a represents the number 2, then b is 1. If a represents the number 1, then b is 2.

[0065] If the index number a stands for the number 2 or 3, several OR 3 Units in the silane molecule of formula (I). In this case, the radical R 3 in each of the OR 3 Units independent of the other OR 3 units can be chosen. For example, if a stands for the number 3, the silane molecule comprises three OR 3Units of which, for example, one unit can represent a hydroxy group and two units can represent an ethoxy group.

[0066] Particularly resistant films could be produced if the aftertreatment agent (N) contains at least one organic silicon compound (N-1) of the formula (I), in which independently of one another the radical R 3 represents a hydrogen atom, a methyl group or an ethyl group and the radical R 4 represents a methyl group or an ethyl group.

[0067] When using the process for dyeing human hair, dyeings with the best wash fastness properties could be obtained if the aftertreatment agent (N) contains at least one organic silicon compound (N-1) of the formula (I), in which, independently of one another, - the remainder R 3 a hydrogen atom is a methyl group or an ethyl group, and - the remainder R 4represents a methyl group or an ethyl group.

[0068] Furthermore, dyeings with the best washfastness properties could be obtained when the aftertreatment agent (N) contains at least one organic silicon compound of the formula (I) in which the radical a represents the number 3. In this case, the radical b represents the number 0.

[0069] In a further preferred embodiment, the aftertreatment agent (N) used in the process is characterized in that it contains at least one organic silicon compound (N-1) of the formula (I), where - R 3 represents a hydrogen atom, a methyl group or an ethyl group, and - R 4 represents a methyl group or an ethyl group, and - a stands for the number 3, and - b stands for the number 0.

[0070] Organic silicon compounds of the formula (I) which are particularly suitable for solving the problem according to the invention are - (3-Aminopropyl)triethoxysilane - (3-Aminopropyl)trimethoxysilane - (2-Aminoethyl)triethoxysilane - (2-Aminoethyl)trimethoxysilane - (3-Dimethylaminopropyl)triethoxysilane - (3-Dimethylaminopropyl)trimethoxysilane - (2-Dimethylaminoethyl)triethoxysilane. - (2-Dimethylaminoethyl)trimethoxysilane and

[0071] The complete hydrolysis product of 3-aminopropyltriethoxysilane and 3-aminopropyltrimethoxysilane is 1-(3-aminopropyl)silanetriol

[0072] The complete hydrolysis product of 3-aminoethyltriethoxysilane and 3-aminoethyltrimethoxysilane is 1-(2-aminoethyl)silanetriol

[0073] In a further preferred embodiment, a process according to the invention is characterized in that the aftertreatment agent (N) contains at least one silane (N-1) selected from the group consisting of - (3-Aminopropyl)triethoxysilane - (3-Aminopropyl)trimethoxysilane - (2-Aminoethyl)triethoxysilane - (2-Aminoethyl)trimethoxysilane - (3-Dimethylaminopropyl)triethoxysilane - (3-Dimethylaminopropyl)trimethoxysilane - (2-Dimethylaminoethyl)triethoxysilane. - (2-Dimethylaminoethyl)trimethoxysilane and / or their hydrolysis and / or condensation products.

[0074] The aforementioned organic silicon compounds of formula (I) are commercially available. (3-Aminopropyl)trimethoxysilane, for example, can be purchased from Sigma-Aldrich. (3-Aminopropyl)triethoxysilane is also commercially available from Sigma-Aldrich.

[0075] In further dyeing tests, it has been found to be particularly advantageous if the aftertreatment agent (N) used in the process additionally contained at least one organic silicon compound (N-1) of the formula (II) R 5 Si(OR 6 ) k (R 7 )m (II).

[0076] The organic silicon compound(s) of formula (II) can also be referred to as silanes of the alkylalkoxysilane or alkylhydroxysilane type, R 5 Si(OR 6 ) k (R 7 )m (II), where - R 5 for a C 1 -C 18 -alkyl group, - R 6 for a hydrogen atom or a C 1 -C 6 -alkyl group, - R 7 for a C 1 -C 6 -alkyl group - k stands for an integer from 1 to 3, and - m stands for the integer 3 - k.

[0077] In a further preferred embodiment, a process according to the invention is characterized in that the aftertreatment agent (N) contains at least one silane (N-1) of the formula (II) and / or its hydrolysis and / or condensation products, R 5 Si(OR 6 ) k (R 7 )m (II), where - R 5 for a C 1 -C 18 -alkyl group, - R 6 for a hydrogen atom or a C 1 -C 6 -alkyl group, - R 7 for a C 1 -C 6 -alkyl group - k stands for an integer from 1 to 3, and - m stands for the integer 3 - k.

[0078] In the organic silicon compounds of formula (II), the radical R 5 for a C 1 -C 18 -alkyl group. This C 1 -C18 -Alkyl group is saturated and can be linear or branched. Preferably, R 5 for a linear C 1 -C 18 -alkyl group. R is preferably 5 represents a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-octyl group, an n-dodecyl group or an n-octadecyl group. R is particularly preferably 5 for a methyl group, an ethyl group, an n-hexyl group or an n-octyl group.

[0079] In the organic silicon compounds of form (II) the radical R 6 for a hydrogen atom or a C 1 -C 6 -alkyl group. R is particularly preferably 6 for a methyl group or for an ethyl group.

[0080] If the index number k stands for the number 2 or 3, several OR 6 Units in the silane molecule of formula (II). In this case, the radical R 6in each of the OR 6 Units independent of the other OR 6 units can be chosen. For example, if k stands for the number 3, the silane molecule comprises three OR 6 Units of which, for example, one unit can represent a hydroxy group and two units can represent an ethoxy group.

[0081] In the organic silicon compounds of form (II) the radical R 7 for a C 1 -C 6 -alkyl group. R is particularly preferably 7 for a methyl group or for an ethyl group.

[0082] Furthermore, k represents an integer from 1 to 3, and m represents the integer 3 - k. If k represents the number 3, then m is equal to 0. If k represents the number 2, then m is equal to 1. If k represents the number 1, then m is equal to 2.

[0083] Particularly stable films, ie dyeings with particularly good wash fastness properties, could be obtained when a post-treatment agent (N) was used in the process which, in addition to the silane(s) (N-1) of formula (I), contained at least one organic silicon compound of formula (II) in which the radical k stands for the number 3. In this case, the radical m stands for the number 0.

[0084] Organic silicon compounds of the formula (II) which are particularly suitable for solving the problem according to the invention are - Methyltrimethoxysilane - Methyltriethoxysilane - Ethyltrimethoxysilane - Ethyltriethoxysilane - n-hexyltrimethoxysilane - n-Hexyltriethoxysilane - n-octyltrimethoxysilane - n-octyltriethoxysilane - n-dodecyltrimethoxysilane and / or - n-dodecyltriethoxysilane, n-octadecyltrimethoxysilane and / or n-octadecyltriethoxysilane.

[0085] In a further preferred embodiment, a process according to the invention is characterized in that the aftertreatment agent (N) contains at least one silane (N-1) selected from the group consisting of - Methyltrimethoxysilane - Methyltriethoxysilane - Ethyltrimethoxysilane - Ethyltriethoxysilane - Propyltrimethoxysilane - Propyltriethoxysilane - Hexyltrimethoxysilane - Hexyltriethoxysilane - Octyltrimethoxysilane - Octyltriethoxysilane - Dodecyltrimethoxysilane, - Dodecyltriethoxysilane, - Octadecyltrimethoxysilane, - Octadecyltriethoxysilane and / or their hydrolysis and / or condensation products.

[0086] It has been found to be preferred if the aftertreatment agent (N) - based on the total weight of the aftertreatment agent (N) - contained one or more organic silicon compounds (N-1) of the formula (I) in a total amount of 0.1 to 20 wt.%, preferably 1 to 15 wt.% and particularly preferably 2 to 12 wt.%.

[0087] Furthermore, it has been found to be preferred if the aftertreatment agent (N) - based on the total weight of the aftertreatment agent (N) - contained one or more organic silicon compounds (N-1) of the formula (I) and the formula (II) in a total amount of 0.1 to 20 wt.%, preferably 1 to 15 wt.% and particularly preferably 2 to 12 wt.%.

[0088] In a further particularly preferred embodiment, a process according to the invention is characterized in that the aftertreatment agent (N) - based on the total weight of the aftertreatment agent (N) - contains one or more organic silicon compounds (N-1) in a total amount of 0.1 to 20 wt.%, preferably 1 to 15 wt.% and particularly preferably 2 to 12 wt.%.

[0089] In an explicitly particularly preferred embodiment, a method is characterized in that a post-treatment agent (N) is applied to the keratinic fibers, which contains at least one organic silicon compound of the formula (I) selected from the group consisting of (3-aminopropyl)triethoxysilane and (3-aminopropyl)trimethoxysilane, and additionally contains at least one organic silicon compound of the formula (II) selected from the group consisting of methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, hexyltrimethoxysilane and hexyltriethoxysilane. Oligomers and / or condensation products of organosilicon compounds

[0090] In the case of the previously described organic silicon compounds or silanes of formulas (I) and (II), even the addition of small amounts of water leads to hydrolysis or oligomerization and / or polymerization. The extent of oligomerization or polymerization depends on the amount of water that comes into contact with the silane(s) of formulas (I) or (II). The aim of the process according to the invention is that the formation of the colored film, i.e. the final polymerization starting from the silanes (N-1), takes place when the aftertreatment agent (N) is already on the keratin fibers. However, due to the high reactivity of the silanes (N-1), oligomerization or precondensation may have already taken place before the aftertreatment agent (N) is applied, and the silanes may already be hydrolyzed, oligomerized or, to a small extent, even polymerized in the aftertreatment agent (N).

[0091] For this reason, both the silanes of formulas (I) and (II) and their hydrolysis products, oligomers, and / or condensation products can be present in the colorant (F). According to the invention, the term "silanes of formula (I) and (II)" therefore also encompasses their hydrolysis products, oligomers, and / or condensation products.

[0092] The corresponding hydrolysis products, oligomers and / or condensation products are, for example, the following compounds.

[0093] Hydrolysis of C 1 -C 6 -Alkoxysilane of formula (I) with water (reaction scheme using the example of 3-aminopropyltriethoxysilane):

[0094] Depending on the amount of water used, the hydrolysis reaction can also be repeated several times per C used. 1 -C 6 -Alkoxy-silane take place:or.

[0095] Hydrolysis of C 1 -C 6-Alkoxysilane of formula (II) with water (reaction scheme using the example of methyltrimethoxysilane):

[0096] Depending on the amount of water used, the hydrolysis reaction can also be repeated several times per C used. 1 -C 6 -Alkoxy-silane take place:or.

[0097] Possible condensation reactions are, for example (shown using the mixture (3-aminopropyl)triethoxysilane and methyltrimethoxysilane): and / or and / or and / or and / or and / or and / or

[0098] In the above exemplary reaction schemes, the condensation to a dimer is shown, but further condensations to oligomers with several silane atoms are also possible and preferred.

[0099] A condensation product is a product formed by the reaction of at least two organic silicon compounds, each containing at least one hydroxyl group or hydrolyzable group per molecule, with the elimination of water and / or an alkanol. The condensation products can be, for example, dimers, but also trimers or oligomers, with the condensation products being in equilibrium with the monomers. Depending on the amount of water used or consumed in the hydrolysis, the equilibrium shifts from monomeric organic silicon compounds to condensation product.

[0100] Particularly good results were obtained when organic silicon compounds of formulas (I) and (II) were used in the process. Since, as already described above, hydrolysis / condensation begins even with traces of moisture, the hydrolysis and / or condensation products of the organic silicon compounds (I) and (II) are also encompassed by this embodiment. Cosmetic carrier of the aftercare product (N)

[0101] The post-treatment agent (N) contains the silane(s) (N-1) and particularly preferably in a cosmetic carrier. The post-treatment agent (N) is preferably formulated with little or no water. Compounds from the group of poly-C, for example, are particularly suitable as cosmetic carriers. 1 -C 6-Alkylene glycols, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, dipropylene glycol, ethanol, isopropanol, diethylene glycol monoethyl ether, glycerin, phenoxyethanol and benzyl alcohol. Poly-C 1 -C 6 -Alkylene glycols, especially polyethylene glycols, have shown particularly good suitability in this regard.

[0102] In a further particularly preferred embodiment, a process according to the invention is characterized in that the aftertreatment agent (N) - based on the total weight of the aftertreatment agent (N) - contains one or more solvents from the group consisting of ethanol, poly-C 1 -C 6 -alkylene glycols, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, dipropylene glycol, ethanol, isopropanol, diethylene glycol monoethyl ether, glycerin, phenoxyethanol and benzyl alcohol.

[0103] As suitable poly-C 1 -C 6-Alkylene glycols can be mentioned in particular the polyethylene glycols, as described for example by the formula (AG) where p represents an integer from 1 to 1000, preferably 1 to 100, particularly preferably 2 to 50.

[0104] The alkylene glycols of formula (AG) are protic substances with at least one hydroxyl group, which, due to their repeating unit -CH2-CH2-O-, can also be referred to as polyethylene glycols, provided p represents a value of at least 2. In the alkylene glycols of formula (AG), p represents an integer from 1 to 10,000. The work leading to this invention has shown that these polyethylene glycols are particularly suitable for improving the fastness properties of colorants and for optimally adjusting the viscosity of the agents.

[0105] 1,2-Propylene glycol is alternatively referred to as 1,2-propanediol and has the CAS numbers 57-55-6 [(RS)-1,2-dihydroxypropane], 4254-14-2 [(R)-1,2-dihydroxypropane], and 4254-153 [(S)-1,2-dihydroxypropane]. 1,3-Propylene glycol is alternatively referred to as 1,3-dihydroxypropane or 1,3-propanediol and has the CAS number 504-63-2. 1,2-Butylene glycol can also be referred to as 1,2-butanediol and has the CAS numbers 584-03-2 (racemate), 40348-66-1 ((R)-enantiomer), and 73522-17-5 ((S)-enantiomer).

[0106] Dipropylene glycols (or oxydipropanols) form a group of substances derived from glycol ethers. The dipropylene glycol group includes 2,2'-oxydi-1-propanol (CAS No. 108-61-2), 1,1'-oxydi-2-propanol (CAS No. 110-98-5), and 2-(2-hydroxypropoxy)-1-propanol (CAS No. 106-62-7). The mixture of these three isomers has CAS No. 25265-71-8.

[0107] Ethanol has the CAS No. 64-17-5. Isopropanol is also known as 2-propanol and has the CAS No. 67-63-0. Ethylene glycol is also known as 1,2-ethanediol and has the CAS No. 107-21-1.

[0108] Diethylene glycol monoethyl ether can alternatively be referred to as ethoxydiglycol or ethyldiglycol or 2-(2-ethoxyethoxy)ethanol) and has the CAS No. 111-90-0.

[0109] Glycerin is also known as 1,2,3-propanetriol and has the CAS number 56-81-5. Phenoxyethanol has the CAS number 122-99-6. Benzyl alcohol can also be known as phenylmethanol and has the CAS number 100-51-6.

[0110] All solvents described above are commercially available from various chemical suppliers such as Aldrich or Fluka.

[0111] A solvent that is particularly suitable for the aftertreatment agent (N) is ethylene glycol, which belongs to the group of poly-C 1 -C 6 -Alkylene glycols and repeating -CH 2 -CH 2 -O-units. Ethylene glycols are compounds of the formula (EG-I)where y represents an integer from 1 to 10000, preferably an integer from 2 to 500, more preferably an integer from 3 to 100 and most preferably an integer from 5 to 30.

[0112] If y stands for the number 1, the ethylene glycol of formula (EG-F) is ethylene glycol itself, which is alternatively called 1,2-ethanediol and has the CAS number 107-21-1.

[0113] The polyethylene glycols of formula (EG-I) are protic substances with at least two hydroxyl groups, which, due to their repeating unit -CH2-CH2-O-, can also be referred to as polyalkylene glycols or polyethylene glycols, since y represents a value of at least 2. In the alkylene glycols of formula (EG-I), y represents an integer from 1 to 10,000. The work leading to this invention has shown that these polyethylene glycols are particularly suitable for improving the fastness properties of aftertreatment agents and for optimally adjusting the viscosity of the agents.

[0114] Depending on their chain length, polyethylene glycols are liquid or solid, water-soluble polymers. Polyethylene glycols with a molecular weight between 200 g / mol and 400 g / mol are non-volatile liquids at room temperature. PEG 600 has a melting range of 17 to 22 °C and thus a paste-like consistency. With molecular weights above 3000 g / mol, PEGs are solid substances and are marketed as flakes or powders.

[0115] The use of low-molecular-weight alkylene glycols (or polyethylene glycols) has proven particularly suitable for achieving the object of the invention. For low-molecular-weight alkylene glycols (or polyethylene glycols) within the meaning of the present invention, y represents an integer from 1 to 100, preferably an integer from 1 to 80, more preferably an integer from 2 to 60, even more preferably an integer from 3 to 40, even more preferably an integer from 4 to 20, and most preferably an integer from 6 to 15.

[0116] In a further particularly preferred embodiment, an agent according to the invention is characterized in that it contains at least one polyethylene glycol of the formula (EG-1a), wherein y1 represents an integer from 2 to 100, preferably an integer from 2 to 80, more preferably an integer from 2 to 60, even more preferably an integer from 3 to 40, even more preferably an integer from 4 to 20 and most preferably an integer from 6 to 15.

[0117] A particularly preferred low-molecular-weight polyethylene glycol is PEG-8. PEG-8 contains an average of 8 ethylene glycol units (y1 = 8), has an average molecular weight of 400 g / mol, and bears the CAS number 25322-68-3. PEG-8 is also referred to as PEG 400 and is commercially available, for example, from APS.

[0118] Other suitable low molecular weight polyethylene glycols include PEG-6, PEG-7, PEG-9 and PEG-10.

[0119] Another suitable polyethylene glycol is PEG-32. PEG-32 contains 32 ethylene glycol units (y1 = 32), has an average molecular weight of 1500 g / mol, and carries the CAS number 25322-68-3. PEG-32 is also known as PEG 1500 and can be purchased commercially, for example, from Clariant.

[0120] Furthermore, the use of high molecular weight polyethylene glycols has also proven to be well suited to solving the problem according to the invention.

[0121] High molecular weight polyethylene glycols in the sense of the present invention can be represented by the formula (EG-1b), where the index number y2 stands for an integer from 101 to 10000

[0122] In the case of particularly suitable high molecular weight polyethylene glycols, y2 represents an integer from 101 to 1000, preferably an integer from 105 to 800, more preferably an integer from 107 to 600, even more preferably an integer from 109 to 400 and most preferably an integer from 110 to 200.

[0123] In a further particularly preferred embodiment, an agent according to the invention is characterized in that it contains at least one alkylene glycol of the formula (EG-1b), wherein y2 represents an integer from 101 to 1000, preferably an integer from 105 to 800, more preferably an integer from 107 to 600, even more preferably an integer from 109 to 400 and most preferably an integer from 110 to 200.

[0124] A particularly suitable high-molecular-weight polyethylene glycol is PEG 6000, which is commercially available from National Starch (China). The molecular weight of PEG 6000 is between 6000 and 7500 g / mol, corresponding to a y2 value of 136 to 171.

[0125] Another suitable polyethylene glycol is PEG 12000, which is marketed commercially by CG Chemikalien, for example, under the trade name Polyethylene Glycol 12000 S (or PEG 12000 S). The molecular weight of PEG 12000 is stated to be between 10,500 and 15,000 g / mol, corresponding to a y2 value of 238 to 341.

[0126] Another suitable polyethylene glycol is PEG 20000, which is commercially available from Clariant under the trade name Polyglycol 20000 P or under the alternative name PEG-350. PEG 20000 has an average molecular weight of 20000 g / mol, which corresponds to a y2 value of 454.

[0127] The solvent(s) are preferably used in specific quantity ranges in the aftertreatment agent (N). The aftertreatment agent (N) preferably contains one or more solvents in a total amount of 10.0 to 99.0 wt. %, preferably 30.0 to 99.0 wt. %, more preferably 50.0 to 99.0 wt. %, and most preferably 70.0 to 99.0 wt. %, based on the total weight of the aftertreatment agent (N).

[0128] Within the scope of a further particularly preferred embodiment, a process according to the invention is therefore characterized in that the aftertreatment agent (N) - based on the total weight of the aftertreatment agent (N) - one or more solvents, preferably ethanol and / or poly-C 1 -C 6 -alkylene glycols, in a total amount of 10.0 to 99.0 wt.%, preferably 30.0 to 99.0 wt.%, more preferably 50.0 to 99.0 wt.% and most preferably 70.0 to 99.0 wt.%.

[0129] In a further particularly preferred embodiment, a process according to the invention is therefore characterized in that the aftertreatment agent (N) contains one or more ethylene glycols of the formula (EG), where y represents an integer from 1 to 10000, preferably an integer from 2 to 500, more preferably an integer from 3 to 100 and most preferably an integer from 5 to 30.

[0130] In a very particularly preferred embodiment, a process according to the invention is characterized in that the aftertreatment agent (N) - based on the total weight of the aftertreatment agent (N) - contains one or more ethylene glycols of the formula (EG) in a total amount of 10.0 to 99.0 wt.%, preferably 30.0 to 99.0 wt.%, more preferably 50.0 to 99.0 wt.% and very particularly preferably 70.0 to 99.0 wt.%, where y represents an integer from 1 to 10000, preferably an integer from 2 to 500, more preferably an integer from 3 to 100 and most preferably an integer from 5 to 30. Water content in the curing agent (N)

[0131] The post-treatment agent (N) is preferably formulated with low water or water-free content.

[0132] For this reason, the aftertreatment agent (N) preferably contains less than 20 wt.% water, based on the total weight of the aftertreatment agent (N). This ensures that the aftertreatment agent (N) remains stable over the entire application period and that premature, undesired oligomerization or polymerization of the silanes can be sufficiently avoided. Even if the stability of the agent can already be ensured at a water content of up to 20 wt.%, it has proven preferable to set the water content of the aftertreatment agent (N) to a value below 10 wt.% in order to further optimize stability. Particularly good results have been obtained when the water content in the aftertreatment agent (N) - based on the total weight of the aftertreatment agent (N) - is 0 to 20.0 wt.%, preferably 0.1 to 10.0 wt.%, more preferably 0.1 to 5.0 wt.-%, and particularly preferably from 0.5 to 3.0 wt.% water.

[0133] In a further particularly preferred embodiment, a process according to the invention is characterized in that the aftertreatment agent (N) - based on the total weight of the aftertreatment agent (N) - contains 0 to 20.0 wt.%, preferably from 0.1 to 10.0 wt.%, more preferably from 0.1 to 5.0 wt.%, and particularly preferably from 0.5 to 3.0 wt.% of water.

[0134] The range from 0 to 20.0 wt.% water means that the agent contains as little water as possible or that the amount of water that may be introduced into the aftertreatment agent (N) by other ingredients contained in the aftertreatment agent (N) does not exceed a content of 20.0 wt.%. Process for coloring keratin fibers

[0135] The successive application of the reducing agent-containing pretreatment agent (V) and the silane-containing post-treatment agent (N) enables the formation of particularly uniform and durable films on the keratin fibers. This formation of uniform films is advantageous in various keratin treatment processes, such as styling or permanent fiber reshaping. However, it is particularly important in the coloring process, as the films are colored by incorporated color-imparting compounds, and uneven removal of the film becomes particularly visible.

[0136] For this reason, the method according to the invention is particularly preferably a method for coloring keratin fibers. The previously described aftertreatment agent (N) is then a colorant (F).

[0137] Most preferably, the method according to the invention is a method for dyeing keratin fibers, in particular human hair, comprising the following steps: - Application of a pretreatment agent (V) to the keratin fibers, wherein the pretreatment agent contains (V-1) at least one reducing agent selected from the group consisting of dithioerythritol, dithiothreitol, acetylcysteine, dimercaptosuccinic acid, thioglycerol, thiolactic acid, sodium dithionite, zinc dithionite, potassium dithionite, formamidine sulfinic acid, 2-hydroxy-2-sulfinoacetic acid and salts thereof, and - Application of a colorant (F) to the keratin fibers, wherein the colorant (F) contains (F-1) at least one organic silicon compound from the group of silanes having one, two or three silicon atoms.

[0138] All previously described embodiments for the aftertreatment agent (N) also apply to the colorant (F).

[0139] Within the scope of a further explicitly particularly preferred embodiment, a method according to the invention is characterized in that it is a method for dyeing keratin fibers, in particular human hair, and in that the aftertreatment agent (N) is a colorant (F) which contains at least one color-providing compound from the group of pigments and direct dyes. Pigments (F-2) in the colorant (F)

[0140] The colorant (F) used in the process according to the invention particularly preferably contains at least one color-providing compound from the group of pigments and direct dyes.

[0141] Most preferably, the method according to the invention is a method for dyeing keratin fibers, in particular human hair, comprising the following steps: - Application of a pretreatment agent (V) to the keratin fibers, wherein the pretreatment agent contains (V-1) at least one reducing agent selected from the group consisting of dithioerythritol, dithiothreitol, acetylcysteine, dimercaptosuccinic acid, thioglycerol, thiolactic acid, sodium dithionite, zinc dithionite, potassium dithionite, formamidine sulfinic acid, 2-hydroxy-2-sulfinoacetic acid and salts thereof, and - Application of a colorant (F) to the keratin fibers, wherein the colorant (F) contains (F-1) at least one organic silicon compound from the group of silanes having one, two or three silicon atoms, and (F-2) at least one pigment.

[0142] Pigments within the meaning of the present invention are understood to be coloring compounds which have a solubility in water at 25°C of less than 0.5 g / L, preferably less than 0.1 g / L, even more preferably less than 0.05 g / L. The water solubility can be determined, for example, using the method described below: 0.5 g of the pigment is weighed into a beaker. A stirring bar is added. Then one liter of distilled water is added. This mixture is heated to 25°C for one hour while stirring on a magnetic stirrer. If undissolved components of the pigment are still visible in the mixture after this period, the solubility of the pigment is below 0.5 g / L. If the pigment-water mixture cannot be visually assessed due to the high intensity of the pigment, which may be present in finely dispersed form, the mixture is filtered.If a portion of undissolved pigments remains on the filter paper, the solubility of the pigment is below 0.5 g / L.

[0143] Suitable color pigments can be of inorganic and / or organic origin.

[0144] In a preferred embodiment, a colorant (F) according to the invention is characterized in that it contains at least one color-providing compound (F-2) from the group of inorganic and / or organic pigments.

[0145] In a preferred embodiment, a colorant (F) according to the invention is characterized in that it contains at least one inorganic and / or organic pigment (F-2).

[0146] Preferred color pigments are selected from synthetic or natural inorganic pigments. Inorganic color pigments of natural origin can be made from chalk, ochre, umber, green earth, burnt sienna, or graphite, for example. Other inorganic color pigments that can be used include black pigments such as iron oxide black, colored pigments such as ultramarine or iron oxide red, as well as fluorescent or phosphorescent pigments.

[0147] Particularly suitable are colored metal oxides, hydroxides, and oxide hydrates, mixed-phase pigments, sulfur-containing silicates, silicates, metal sulfides, complex metal cyanides, metal sulfates, chromates, and / or molybdates. Particularly preferred color pigments are black iron oxide (CI 77499), yellow iron oxide (CI 77492), red and brown iron oxide (CI 77491), manganese violet (CI 77742), ultramarines (sodium aluminum sulfosilicates, CI 77007, Pigment Blue 29), chromium oxide hydrate (CI 77289), iron blue (ferric ferrocyanide, CI 77510), and / or carmine (cochineal).

[0148] Also particularly preferred color pigments according to the invention are colored pearlescent pigments. These are typically based on mica and / or mica and can be coated with one or more metal oxides. Mica belongs to the class of layered silicates. The most important representatives of these silicates are muscovite, phlogopite, paragonite, biotite, lepidolite, and margarite. To produce the pearlescent pigments in combination with metal oxides, the mica, predominantly muscovite or phlogopite, is coated with a metal oxide.

[0149] As an alternative to natural mica, synthetic mica, optionally coated with one or more metal oxides, can also be used as a pearlescent pigment. Particularly preferred pearlescent pigments are based on natural or synthetic mica and coated with one or more of the aforementioned metal oxides. The color of the respective pigments can be varied by varying the layer thickness of the metal oxide(s).

[0150] In a further preferred embodiment, a process according to the invention is characterized in that the colorant (F) contains at least inorganic pigment (F-2), which is preferably selected from the group of colored metal oxides, metal hydroxides, metal oxide hydrates, silicates, metal sulfides, complex metal cyanides, metal sulfates, bronze pigments and / or colored pigments based on mica or mica, which are coated with at least one metal oxide and / or one metal oxychloride.

[0151] In a further preferred embodiment, a process according to the invention is characterized in that the colorant (F) contains at least one pigment selected from mica- or mica-based pigments coated with one or more metal oxides from the group consisting of titanium dioxide (CI 77891), black iron oxide (CI 77499), yellow iron oxide (CI 77492), red and / or brown iron oxide (CI 77491, CI 77499), manganese violet (CI 77742), ultramarines (sodium aluminum sulfosilicates, CI 77007, Pigment Blue 29), chromium oxide hydrate (CI 77289), chromium oxide (CI 77288) and / or iron blue (ferric ferrocyanide, CI 77510).

[0152] Examples of particularly suitable color pigments are commercially available under the trade names Rona®, Colorona®, Xirona®, Dichrona® and Timiron® from Merck, Ariabel® and Unipure® from Sensient, Prestige® from Eckart Cosmetic Colors and Sunshine® from Sunstar.

[0153] Particularly preferred color pigments with the trade name Colorona® are, for example: Colorona Copper, Merck, MICA, CI 77491 (IRON OXIDES) Colorona Passion Orange, Merck, Mica, CI 77491 (Iron Oxides), Alumina Colorona Patina Silver, Merck, MICA, CI 77499 (IRON OXIDES), CI 77891 (TITANIUM DIOXIDE) Colorona RY, Merck, CI 77891 (TITANIUM DIOXIDE), MICA, CI 75470 (CARMINE) Colorona Oriental Beige, Merck, MICA, CI 77891 (TITANIUM DIOXIDE), CI 77491 (IRON OXIDES) Colorona Dark Blue, Merck, MICA, TITANIUM DIOXIDE, FERRIC FERROCYANIDE Colorona Chameleon, Merck, CI 77491 (IRON OXIDES), MICA Colorona Aborigine Amber, Merck, MICA, CI 77499 (IRON OXIDES), CI 77891 (TITANIUM DIOXIDE) Colorona Blackstar Blue, Merck, CI 77499 (IRON OXIDES), MICA Colorona Patagonian Purple, Merck, MICA, CI 77491 (IRON OXIDES), CI 77891 (TITANIUM DIOXIDE), CI 77510 (FERRIC FERROCYANIDE) Colorona Red Brown, Merck, MICA, CI 77491 (IRON OXIDES), CI 77891 (TITANIUM DIOXIDE) Colorona Russet, Merck, CI 77491 (TITANIUM DIOXIDE), MICA, CI 77891 (IRON OXIDES) Colorona Imperial Red, Merck, MICA, TITANIUM DIOXIDE (CI 77891), D&C RED NO. 30 (CI 73360) Colorona Majestic Green, Merck, CI 77891 (TITANIUM DIOXIDE), MICA, CI 77288 (CHROMIUM OXIDE GREENS) Colorona Light Blue, Merck, MICA, TITANIUM DIOXIDE (CI 77891), FERRIC FERROCYANIDE (CI 77510) Colorona Red Gold, Merck, MICA, CI 77891 (TITANIUM DIOXIDE), CI 77491 (IRON OXIDES) Colorona Gold Plus MP 25, Merck, MICA, TITANIUM DIOXIDE (CI 77891), IRON OXIDES (CI 77491) Colorona Carmine Red, Merck, MICA, TITANIUM DIOXIDE, CARMINE Colorona Blackstar Green, Merck, MICA, CI 77499 (IRON OXIDES) Colorona Bordeaux, Merck, MICA, CI 77491 (IRON OXIDES) Colorona Bronze, Merck, MICA, CI 77491 (IRON OXIDES) Colorona Bronze Fine, Merck, MICA, CI 77491 (IRON OXIDES) Colorona Fine Gold MP 20, Merck, MICA, CI 77891 (TITANIUM DIOXIDE), CI 77491 (IRON OXIDES) Sienna Fine Color, Merck, CI 77491 (IRON OXIDES), MICA Sienna Color, Merck, MICA, CI 77491 (IRON OXIDES) Colorona Precious Gold, Merck, Mica, CI 77891 (Titanium dioxide), Silica, CI 77491 (Iron oxides), Tin oxide Colorona Sun Gold Sparkle MP 29, Merck, MICA, TITANIUM DIOXIDE, IRON OXIDES, MICA, CI 77891, CI 77491 (EU) Colorona Mica Black, Merck, CI 77499 (Iron oxides), Mica, CI 77891 (Titanium dioxide) Colorona Bright Gold, Merck, Mica, CI 77891 (Titanium dioxide), CI 77491 (Iron oxides) Colorona Blackstar Gold, Merck, MICA, CI 77499 (IRON OXIDES)

[0154] Other particularly preferred color pigments with the trade name Xirona® include: Xirona Golden Sky, Merck, Silica, CI 77891 (Titanium Dioxide), Tin Oxide Xirona Caribbean Blue, Merck, Mica, CI 77891 (Titanium Dioxide), Silica, Tin Oxide Xirona Kiwi Rose, Merck, Silica, CI 77891 (Titanium Dioxide), Tin Oxide Xirona Magic Mauve, Merck, Silica, CI 77891 (Titanium Dioxide), Tin Oxide.

[0155] In addition, particularly preferred color pigments with the trade name Unipure® are, for example: Unipure Red LC 381 EM, Sensient CI 77491 (Iron Oxides), Silica Unipure Black LC 989 EM, Sensient, CI 77499 (Iron Oxides), Silica Unipure Yellow LC 182 EM, Sensient, CI 77492 (Iron Oxides), Silica

[0156] In a further embodiment, the colorant (F) according to the invention may also contain one or more organic pigments

[0157] The organic pigments according to the invention are correspondingly insoluble, organic dyes or lakes which can be selected, for example, from the group of nitroso, nitro, azo, xanthene, anthraquinone, isoindolinone, isoindoline, quinacridone, perinone, perylene, diketopyrrolopyorrole, indigo, thioindido, dioxazine and / or triarylmethane compounds.

[0158] Particularly suitable organic pigments are, for example, carmine, quinacridone, phthalocyanine, sorghum, blue pigments with the color index numbers CI 42090, CI 69800, CI 69825, CI 73000, CI 74100, CI 74160, yellow pigments with the color index numbers CI 11680, CI 11710, CI 15985, CI 19140, CI 20040, CI 21100, CI 21108, CI 47000, CI 47005, green pigments with the color index numbers CI 61565, CI 61570, CI 74260, orange pigments with the color index numbers CI 11725, CI 15510, CI 45370, CI 71105, red pigments with the Color index numbers CI 12085, CI 12120, CI 12370, CI 12420, CI 12490, CI 14700, CI 15525, CI 15580, CI 15620, CI 15630, CI 15800, CI 15850, CI 15865, CI 15880, CI 17200, CI 26100, CI 45380, CI 45410, CI 58000, CI 73360, CI 73915 and / or CI 75470.

[0159] In a further particularly preferred embodiment, a process according to the invention is characterized in that the colorant (F) contains at least one organic pigment (F-2), which is preferably selected from the group consisting of carmine, quinacridone, phthalocyanine, sorghum, blue pigments with the color index numbers CI 42090, CI 69800, CI 69825, CI 73000, CI 74100, CI 74160, yellow pigments with the color index numbers CI 11680, CI 11710, CI 15985, CI 19140, CI 20040, CI 21100, CI 21108, CI 47000, CI 47005, green pigments with the color index numbers CI 61565, CI 61570, CI 74260, orange pigments with the color index numbers CI 11725, CI 15510, CI 45370, CI 71105, red pigments with the color index numbers CI 12085, CI 12120, CI 12370, CI 12420, CI 12490, CI 14700, CI 15525, CI 15580, CI 15620, CI 15630, CI 15800, CI 15850, CI 15865, CI 15880, CI 17200, CI 26100, CI 45380, CI 45410, CI 58000, CI 73360, CI 73915 and / or CI 75470.

[0160] The organic pigment can also be a colored lake. For the purposes of the invention, the term colored lake refers to particles comprising a layer of absorbed dyes, the particle-dye unit being insoluble under the above-mentioned conditions. The particles can be, for example, inorganic substrates, which can be aluminum, silica, calcium borosilicate, calcium aluminum borosilicate, or even aluminum.

[0161] Alizarin varnish, for example, can be used as a colored varnish.

[0162] Due to their excellent light and temperature stability, the use of the aforementioned pigments in the colorant (F) of the process according to the invention is very particularly preferred. Furthermore, it is preferred if the pigments used have a specific particle size. It is therefore advantageous according to the invention if the at least one pigment has an average particle size D 50 from 1.0 to 50 µm, preferably from 5.0 to 45 µm, preferably from 10 to 40 µm, in particular from 14 to 30 µm. The average particle size D 50 can be determined, for example, using dynamic light scattering (DLS).

[0163] Pigments with a specific shape can also be used to color the keratin fibers. For example, a pigment based on a lamellar and / or lenticular substrate plate can be used. Furthermore, coloring based on a substrate plate containing a vacuum-metallized pigment is also possible.

[0164] In a further preferred embodiment, an agent according to the invention is characterized in that it contains at least one pigment selected from the group of pigments based on a lamellar substrate platelet, pigments based on a lenticular substrate platelet and vacuum metallized pigments.

[0165] The substrate platelets of this type have an average thickness of at most 50 nm, preferably less than 30 nm, more preferably at most 25 nm, for example at most 20 nm. The average thickness of the substrate platelets is at least 1 nm, preferably at least 2.5 nm, more preferably at least 5 nm, for example at least 10 nm. Preferred ranges for the thickness of the substrate platelets are 2.5 to 50 nm, 5 to 50 nm, 10 to 50 nm; 2.5 to 30 nm, 5 to 30 nm, 10 to 30 nm; 2.5 to 25 nm, 5 to 25 nm, 10 to 25 nm, 2.5 to 20 nm, 5 to 20 nm and 10 to 20 nm. Each substrate platelet preferably has a thickness that is as uniform as possible. Due to the low thickness of the substrate platelets, the pigment has particularly high hiding power.

[0166] The substrate platelets are preferably monolithic in structure. Monolithic in this context means consisting of a single, closed unit without fractures, stratification, or inclusions, although structural changes may occur within the substrate platelets. The substrate platelets are preferably homogeneous in structure, meaning that no concentration gradient occurs within the platelets. In particular, the substrate platelets are not layered and do not contain any particles or particles distributed within them.

[0167] The size of the substrate platelet can be tailored to the specific application, especially the desired effect on the keratinous material. Typically, the substrate platelets have an average diameter of approximately 2 to 200 µm, particularly approximately 5 to 100 µm.

[0168] In a preferred embodiment, the aspect ratio, expressed as the ratio of the average size to the average thickness, is at least 80, preferably at least 200, more preferably at least 500, and particularly preferably more than 750. The average size of the uncoated substrate platelets is understood to be the d50 value of the uncoated substrate platelets. Unless otherwise stated, the d50 value was determined using a Sympatec Helos device with Quixel wet dispersion. For sample preparation, the sample to be tested was predispersed in isopropanol for 3 minutes.

[0169] The substrate platelets can be made of any material that can be formed into platelets.

[0170] They can be of natural origin or synthetically produced. Materials from which the substrate platelets can be constructed include metals and metal alloys, metal oxides, preferably aluminum oxide, inorganic compounds and minerals such as mica and (semi-)precious stones, as well as plastics. The substrate platelets are preferably made of metal (alloys).

[0171] Any metal suitable for metallic luster pigments can be considered. Such metals include iron and steel, as well as all air- and water-resistant (semi)metals such as platinum, zinc, chromium, molybdenum, and silicon, as well as their alloys such as aluminum bronze and brass. Preferred metals are aluminum, copper, silver, and gold. Preferred substrate platelets are aluminum platelets and brass platelets, with aluminum platelets being particularly preferred.

[0172] Lamellar substrate platelets are characterized by an irregularly structured edge and are also called “cornflakes” due to their appearance.

[0173] Due to their irregular structure, pigments based on lamellar substrate platelets generate a high degree of scattered light. Furthermore, pigments based on lamellar substrate platelets do not completely cover the existing color of a keratinous material, and effects similar to natural graying can be achieved, for example.

[0174] Lenticular (= lens-shaped) substrate platelets have a generally regular, round edge and are also called "silver dollars" due to their appearance. Due to their regular structure, the proportion of reflected light predominates in pigments based on lenticular substrate platelets.

[0175] Vacuum metallized pigments (VMPs) can be obtained, for example, by releasing metals, metal alloys, or metal oxides from appropriately coated foils. They are characterized by a particularly thin substrate platelet thickness in the range of 5 to 50 nm and a particularly smooth surface with increased reflectivity. Substrate platelets comprising a vacuum-metallized pigment are also referred to as VMP substrate platelets in this application. VMP substrate platelets made of aluminum can be obtained, for example, by releasing aluminum from metallized foils.

[0176] The substrate plates made of metal or metal alloy can be passivated, for example by anodizing (oxide layer) or chromating.

[0177] Uncoated lamellar, lenticular, and / or VPM substrate plates, especially those made of metal or metal alloy, reflect incident light to a high degree and produce a light-dark flop. These have proven particularly preferred for use in the dye.

[0178] Suitable pigments based on a lamellar substrate platelet include, for example, the pigments of the VISIONAIRE series from Eckart.

[0179] Pigments based on a lenticular substrate platelet are available, for example, under the name Alegrace® Gorgeous from Schlenk Metallic Pigments GmbH.

[0180] Pigments based on a substrate platelet comprising a vacuum metallized pigment are available, for example, under the name Alegrace® Marvelous or Alegrace® Aurous from Schlenk Metallic Pigments GmbH.

[0181] In a further particularly preferred embodiment, a process according to the invention is characterized in that the colorant (F) contains at least one pigment (F-2) from the group consisting of inorganic pigments, organic pigments, pigments based on a lamellar substrate platelet, pigments based on a lenticular substrate platelet and / or vacuum metallized pigments.

[0182] The pigment(s) (F-2) represent(s) the second essential constituent of the colorant (F) according to the invention and are preferably used in the composition in specific quantity ranges. Particularly good results were obtained when the colorant—based on the total weight of the colorant—contained one or more pigments (F-2) in a total amount of 0.01 to 10.0 wt. %, preferably 0.1 to 5.0 wt. %, more preferably 0.2 to 2.5 wt. %, and most preferably 0.25 to 1.5 wt. %.

[0183] In a further very particularly preferred embodiment, a process according to the invention is characterized in that the colorant (F) - based on the total weight of the colorant (F) - contains one or more pigments (F-2) in a total amount of 0.01 to 10.0 wt.%, preferably 0.1 to 5.0 wt.%, more preferably from 0.2 to 2.5 wt.% and very particularly preferably from 0.25 to 1.5 wt.%. Direct dyes in the dyeing agent (F)

[0184] In principle, the coloring agents (F) used in the process according to the invention can also contain one or more direct dyes as optional components. Direct dyes are dyes that are absorbed directly onto the hair and do not require an oxidative process to develop the color. Direct dyes are typically nitrophenylenediamines, nitroaminophenols, azo dyes, anthraquinones, triarylmethane dyes, or indophenols.

[0185] The direct dyes according to the present invention have a solubility in water (760 mmHg) at 25°C of more than 0.5 g / L and are therefore not considered pigments. Preferably, the direct dyes according to the present invention have a solubility in water (760 mmHg) at 25°C of more than 1.0 g / L.

[0186] The essential advantage of the process according to the invention, however, is that the colorations achievable with the pigment-based colorant (F) are, on the one hand, very wash-stable, but, on the other hand, also possess very high shade stability and can be completely removed again with a suitable color stripping agent. This means that fading of the color, provided it occurs to a reduced extent after several washes of the keratin material, occurs while maintaining the color shade without any visible color shift. This shade stability can be observed even when the colorant (F) contains a mixture of pigments (F-2) of different colors.

[0187] Without being committed to this theory, it is assumed in this context that the reason for the high stability of the color nuance is that all pigments are deposited in the form of a film on the surface of the keratin material. Unlike direct dyes, the pigments cannot diffuse into the keratin material, and also unlike direct dyes, the size or structure of a pigment cannot influence its depth of penetration into the keratin material.

[0188] If a mixture of direct dyes of different colors is applied to the keratin material, these different dyes are usually based on different chromophoric structures and molecules of different sizes. Due to their structural differences, these different dyes can diffuse to different depths into the keratin material and are also washed out of the keratin material to varying degrees during washing. Particularly with natural-toned colorations, which are created, for example, by using a mixture of a yellow, a red, and a blue direct dye, a color shift from brown to yellowish, reddish, or bluish can be observed over the course of several washes or shampoos.

[0189] The colorations produced using the process according to the invention are based on a pigment-silane condensate film located on the surface of the keratin material. Washing tests have now shown that although repeated washings lead to a slight reduction in color intensity, there is no shift in the color tone. The dissolution of different colored pigments from the film during a hair wash is therefore much more uniform.

[0190] The fact that this color shift does not occur when using the process according to the invention is a significant advantage over a dyeing system based on direct dyes. For this reason, it is particularly preferred if the dyeing agent (F) contains no direct dyes or contains them in only very small amounts.

[0191] In a further, very particularly preferred embodiment, a process according to the invention is characterized in that the total amount of the direct dyes contained in the colorant (F) - based on the total weight of the colorant (F) - is below 0.1% by weight, preferably below 0.05% by weight, more preferably below 0.01% by weight and very particularly preferably below 0.001% by weight.

[0192] In other words, in a further very particularly preferred embodiment, a process according to the invention is characterized in that the total amount of the direct dyes contained in the colorant (F) - based on the total weight of the colorant (F) - is below 0.1 wt.%, preferably below 0.05 wt.%, more preferably below 0.01 wt.% and very particularly preferably below 0.001 wt.%, wherein the direct dyes are characterized in that they have a solubility in water (760 mmHg) at 25 °C of more than 0.5 g / L.

[0193] In a further, very particularly preferred embodiment, a process according to the invention is characterized in that the colorant (F) is free from direct dyes.

[0194] Direct dyes can be divided into anionic, cationic and non-ionic direct dyes.

[0195] Kationische direktziehende Farbstoffe sind beispielsweise Basic Blue 7, Basic Blue 26, HC Blue 16, Basic Violet 2 und Basic Violet 14, Basic Yellow 57, Basic Red 76, Basic Blue 16, Basic Blue 347 (Cationic Blue 347 / Dystar), HC Blue No. 16, Basic Blue 99, Basic Brown 16, Basic Brown 17, Basic Yellow 57, Basic Yellow 87, Basic Orange 31, Basic Red 51 Basic Red 76.

[0196] Examples of non-ionic direct dyes include non-ionic nitro and quinone dyes and neutral azo dyes. Examples of non-ionic direct dyes are those known under the international designations "N" and "N" respectively.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-nitrobenzol, 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-Nitro-1,2,3,4-tetrahydrochinoxalin, 2-Hydroxy-1,4-naphthochinon, Pikraminsäure und deren Salze, 2-Amino-6-chloro-4-nitrophenol, 4-Ethylamino-3-nitrobenzoesäure und 2-Chlor-6-ethylamino-4-nitrophenol.

[0197] Anionic direct dyes are also called acid dyes. Acid dyes are understood to be direct dyes that contain at least one carboxylic acid group (-COOH) and / or one sulfonic acid group (-SO 3 H). Depending on the pH value, the protonated forms (-COOH, -SO 3 H) the carboxylic acid or sulfonic acid groups with their deprotonated forms (-COO - , -SO 3 - presumably) in equilibrium. With decreasing pH, the proportion of protonated forms increases. If direct dyes are used in the form of their salts, the carboxylic acid groups or sulfonic acid groups are present in deprotonated form and are neutralized with corresponding stoichiometric equivalents of cations to maintain electroneutrality. Acid dyes according to the invention can also be used in the form of their sodium salts and / or their potassium salts.

[0198] The acid dyes according to the present invention have a solubility in water (760 mmHg) at 25°C of more than 0.5 g / L and are therefore not considered pigments. Preferably, the acid dyes according to the present invention have a solubility in water (760 mmHg) at 25°C of more than 1.0 g / L.

[0199] The alkaline earth metal salts (such as calcium and magnesium salts) and aluminum salts of acid dyes often have lower solubility than the corresponding alkali metal salts. If the solubility of these salts is below 0.5 g / L (25 °C, 760 mmHg), they do not fall under the definition of a direct dye.

[0200] A key feature of acid dyes is their ability to form anionic charges, with the carboxylic acid or sulfonic acid groups responsible for this being typically linked to various chromophoric systems. Suitable chromophoric systems can be found, for example, in the structures of nitrophenylenediamines, nitroaminophenols, azo dyes, anthraquinone dyes, triarylmethane dyes, xanthene dyes, rhodamine dyes, oxazine dyes, and / or indophenol dyes.

[0201] Als Beispiele für Säurefarbstoffe können kennen genannt green: Acid Yellow 1 (D&C Yellow 7, Citronin A, Ext. D&C Yellow No. 7, Japan Yellow 403,CI 10316, COLIPA n°C0 B001), Acid Yellow, C&5 N°3 : Quinoline Yellow, E104, Food Yellow 13), Acid Yellow 9 (CI 13015), Acid Yellow 17 (CI 18965), Acid Yellow 23 (COLIPA n° C 29, Covacap Jaune W 1100 (LCW), Sicovit Tartrazine,10 Tartrazine 25 (LCW) Japan Yellow 4, FD&C Yellow No. 5), Acid Yellow 36 (CI 13065), Acid Yellow 121 (CI 18690), Acid Orange 6 (CI 14270), Acid Orange 7 (2-Naphthol orange, Orange II, CI 15CLIPA n,D&4 10 (CI 16230; Orange G sodium salt), Acid Orange 11 (CI 45370), Acid Orange 15 (CI 50120), Acid Orange 20 (CI 14600), Acid Orange 24 (BROWN 1;CI20170;KATSU201;nosodiumsalt;Brown No.201;RESORCIN BROWN;ACID ORANGE 24;Japan Brown 201;D & C Brown No.1), Acid Red 14 (C.I.14720), Acid Red 18 (E124, Red 18; CI 16255), Acid Red 27 (E 123, CI 16185, C-Rot 46, Echtrot D, FD&C Red Nr.2, Food Red 9, Naphtholrot S), Acid Red 33 (Red 33, Fuchsia Red, D&C Red 33, CI 17200), Acid Red 35 (CI C.I.18065), Acid Red 51 (CI 45430, Pyrosin B, Tetraiodfluorescein, Eosin J, lodeosin), Acid Red 52 (CI 45100, Food Red 106, Solar Rhodamine B, Acid Rhodamine B, Red n° 106 Pontacyl Brilliant Pink), Acid Red 73 (CI CI 27290), Acid Red 87 (Eosin, CI 45380), Acid Red 92 (COLIPA n° C53, CI 45410), Acid Red 95 (CI 45425, Erythtosine,Simacid Erythrosine Y), Acid Red 184 (CI 15685), Acid Red 195, Acid Violet 43 (Jarocol Violet 43, Ext. D&C Violet n° 2, C.I.60730, COLIPA n° C063), Acid Violet 49 (CI 42640), Acid Violet 50 (CI 50325), Acid Blue 1 (Patent Blue, CI 42045), Acid Blue 3 (Patent Blau V, CI 42051), Acid Blue 7 (CI 42080), Acid Blue 104 (CI 42735), Acid Blue 9 (E 133, Patentblau AE, Amidoblau AE, Erioglaucin A, CI 42090, C.I. Food Blue 2), Acid Blue 62 (CI 62045), Acid Blue 74 (E 132, CI 73015), Acid Blue 80 (CI 61585), Acid Green 3 (CI 42085, Foodgreen1), Acid Green 5 (CI 42095), Acid Green 9 (C.I.42100), Acid Green 22 (C.I.42170), Acid Green 25 (CI 61570, Japan Green 201, D&C Green No. 5), Acid Green 50 (Brillantsäuregrün BS, C.I. 44090, Acid Brilliant Green BS, E 142), Acid Black 1 (Black n° 401, Naphthalene Black 10B, Amido Black 10B, CI 20 470, COLIPA n° B15), Acid Black 52 (CI 15711), Food Yellow 8 (CI 14270), Food Blue 5, D&C Yellow 8, D&C Green 5, D&C Orange 10, D&C Orange 11, D&C Red 21, D&C Red 27, D&C Red 33, D&C Violet 2 und / oder D&C Brown 1.

[0202] The water solubility of direct dyes can be determined, for example, as follows: 0.1 g of the direct dye is placed in a beaker. A stir bar is attached. Then 100 ml of water is added. This mixture is heated to 25 °C on a magnetic stirrer while stirring. It is stirred for 60 minutes. The aqueous mixture is then visually assessed. If undissolved residues remain, the amount of water is increased – for example, in 10 ml increments. Water is added until the added amount of dye has completely dissolved. If the dye-water mixture cannot be visually assessed due to the high intensity of the dye, the mixture is filtered. If a portion of undissolved dye remains on the filter paper, the solubility test is repeated using a larger amount of water.If 0.1 g of the anionic direct dye dissolves in 100 ml of water at 25 °C, the solubility of the dye is 1.0 g / L.

[0203] Acid Yellow 1 is called 8-hydroxy-5,7-dinitro-2-naphthalenesulfonic acid disodium salt and has a solubility in water of at least 40 g / L (25°C).

[0204] Acid Yellow 3 is a mixture of the sodium salts of mono- and disulfonic acids of 2-(2-quinolyl)-1H-indene-1,3(2H)-dione and has a water solubility of 20 g / L (25 °C).

[0205] Acid Yellow 9 is the disodium salt of 8-hydroxy-5,7-dinitro-2-naphthalenesulfonic acid, its water solubility is above 40 g / L (25 °C).

[0206] Acid Yellow 23 is the trisodium salt of 4,5-dihydro-5-oxo-1-(4-sulfophenyl)-4-((4-sulfophenyl)azo)-1H-pyrazole-3-carboxylic acid and is readily soluble in water at 25 °C.

[0207] Acid Orange 7 is the sodium salt of 4-[(2-hydroxy-1-naphthyl)azo]benzenesulfonate. Its water solubility is greater than 7 g / L (25 °C).

[0208] Acid Red 18 is the trisodium salt of 7-hydroxy-8-[(E)-(4-sulfonato-1-naphthyl)-diazenyl]-1,3-naphthalenedisulfonate and has a very high water solubility of more than 20 wt%. Acid Red 33 is the disodium salt of 5-amino-4-hydroxy-3-(phenylazo)-naphthalene-2,7-disulfonate; its water solubility is 2.5 g / L (25 °C).

[0209] Acid Red 92 is the disodium salt of 3,4,5,6-tetrachloro-2-(1,4,5,8-tetrabromo-6-hydroxy-3-oxoxanthen-9-yl)benzoic acid, whose water solubility is stated to be greater than 10 g / L (25 °C).

[0210] Acid Blue 9 is the disodium salt of 2-({4-[N-ethyl(3-sulfonatobenzyl]amino]phenyl}{4-[(N-ethyl(3-sulfonatobenzyl)imino]-2,5-cyclohexadien-1-ylidene}methyl)-benzenesulfonate and has a water solubility of more than 20 wt% (25 °C). further optional ingredients in the agents (V) and / or (N)

[0211] In addition to the components already described which are essential to the invention, the pretreatment agent (V) and / or the posttreatment agent (N) (or the colorant (F)) may also contain further optional ingredients.

[0212] The products may also contain other active ingredients, auxiliary substances and additives, such as solvents, fatty components such as C 8 -C 30 -fatty alcohols, the C 8 -C 30 -fatty acid triglycerides, the C 8 -C 30 -fatty acid monoglycerides, the C 8 -C 30-Fatty acid diglycerides and / or hydrocarbons; surfactants or emulsifiers, polymers; structuring agents such as glucose, maleic acid and lactic acid, hair conditioning compounds such as phospholipids, for example lecithin and cephalins; perfume oils, dimethyl isosorbide and cyclodextrins; fiber structure-improving agents, in particular mono-, di- and oligosaccharides such as glucose, galactose, fructose, fructose and lactose; dyes for coloring the product; anti-dandruff agents such as piroctone olamine, zinc omadine and climbazole; amino acids and oligopeptides; protein hydrolysates of animal and / or plant origin, as well as in the form of their fatty acid condensation products or optionally anionically or cationically modified derivatives; vegetable oils; light protectants and UV blockers; Active ingredients such as panthenol, pantothenic acid, pantolactone, allantoin, pyrrolidinone carboxylic acids and their salts and bisabolol;Polyphenols, in particular hydroxycinnamic acids, 6,7-dihydroxycoumarins, hydroxybenzoic acids, catechins, tannins, leucoanthocyanidins, anthocyanidins, flavanones, flavones and flavonols; ceramides or pseudoceramides; vitamins, provitamins and vitamin precursors; plant extracts; fats and waxes such as fatty alcohols, beeswax, montan wax and paraffins; swelling and penetrating agents such as glycerol, propylene glycol monoethyl ether, carbonates, hydrogen carbonates, guanidines, ureas and primary, secondary and tertiary phosphates; opacifiers such as latex, styrene / PVP and styrene / acrylamide copolymers; pearlescent agents such as ethylene glycol mono- and distearate and PEG-3 distearate; and propellants such as propane-butane mixtures, N; 2 O, dimethyl ether, CO 2 and air.

[0213] The expert will select these additional substances based on the desired properties of the agent. Regarding further optional components and the amounts of these components used, reference is expressly made to the relevant manuals known to the expert. The additional active ingredients and excipients are preferably used in the preparations according to the invention in amounts of 0.0001 to 25 wt.%, in particular 0.0005 to 15 wt.%, based on the total weight of the respective agent. Sequence of procedural steps

[0214] In the context of the method according to the invention, in a first step, the pretreatment agent (V) can be applied to the dry or recently moistened keratin fibers.

[0215] In another embodiment, it is also conceivable to additionally pre-shampoo the keratin fibers prior to applying the pre-treatment agent (V). This pre-washing can be particularly useful if the keratin fibers or hair are coated with various conditioning substances due to the previous application of a conditioning agent, which are best removed from the fibers for the reductive pre-treatment.

[0216] In principle, the user can freely choose the time interval between the application of the two products (V) and (N). However, it may be preferable that no other products, such as other conditioners or styling products, be applied between the application of the two products (V) and (N). For this reason, the maximum time interval between the application of the two products (V) and (N) is preferably limited to a maximum of 24 hours.

[0217] Particularly preferred is therefore a method for treating keratin fibers, comprising the steps in the given order: - if necessary, application of a pre-shampoo on the keratin fibers, then - Application of the pre-treatment agent (V) on the keratin fibers, then - Application of the after-treatment agent (N) to the keratin fibers, wherein between the application of the pre-treatment agent (V) and the application of the after-treatment agent (N) there is a period of maximum 24 hours, preferably of maximum 12 hours, more preferably of maximum 6 hours and most preferably of maximum 3 hours.

[0218] Therefore, a method for dyeing keratin fibers comprising the steps in the given order is explicitly preferred: - if necessary, application of a pre-shampoo on the keratin fibers, then - Application of the pre-treatment agent (V) on the keratin fibers, then - Application of the coloring agent (F) to the keratin fibers, wherein between the application of the pretreatment agent (V) and the application of the coloring agent (F) there is a period of maximum 24 hours, preferably of maximum 12 hours, more preferably of maximum 6 hours and most preferably of maximum 3 hours.

[0219] Also particularly preferred is a method for treating keratin fibers, in particular human hair, comprising the following steps in the order given: (1) if necessary, washing the keratin fibers with a pre-shampoo, (2) Applying the pretreatment agent (V) to the keratin fibers, (3) Allowing the pretreatment agent (V) applied in step (2) to act on the keratin fibres for a period of 1 to 45 minutes, preferably 5 to 30 minutes, (4) if necessary, rinsing out the pretreatment agent (V) with water or with the aid of water and a shampoo, (5) if necessary, drying the keratin fibres, (6) Applying the after-treatment agent (N), preferably the coloring agent (F), to the keratin fibers, and (7) Action of the after-treatment agent (N) on the keratin fibers.

[0220] The pre-cleaning of the keratin fibers in step (1) before the actual procedure can be done with a commercially available shampoo, which is rinsed out of the keratin fibers after the cleaning step.

[0221] In step (2), the pretreatment agent (V) is then applied to the keratin fibers or the hair. The pretreatment agent (V) is preferably applied to the still-damp keratin fibers.

[0222] In the subsequent step (3), the previously applied pretreatment agent (V) is allowed to act on the keratin fibers. Various exposure times from 1 to 45 minutes, preferably from 5 to 30 minutes, are possible.

[0223] After the pretreatment agent (V) has acted on the keratin fibers, it can finally be rinsed out with water in step (4). The pretreatment agent (V) can either be washed out with water alone, i.e., without the aid of a shampoo, or the washing-out process can be assisted by using a shampoo. It has proven preferable to rinse the pretreatment agent (V) out of the keratin fibers or hair before applying the post-treatment agent (N).

[0224] In step (5), the keratin fibers can then be dried if necessary. However, it is also possible to apply the post-treatment agent (N) to the still-damp keratin fibers after washing out the pre-treatment agent (V). In this embodiment, step (5) is omitted.

[0225] In step (6) the after-treatment agent (N) is then applied to the keratin fibers.

[0226] The action of the after-treatment agent (N) on the keratin fibers in step (7) can, for example, take place for a period of 15 seconds to 30 minutes, preferably for a period of 30 seconds to 15 minutes, particularly preferably for a period of 1 to 15 minutes.

[0227] Most particularly preferred is a method for dyeing keratin fibers, in particular human hair, comprising the following steps in the order given: (1) if necessary, washing the keratin fibers with a pre-shampoo, (2) Applying the pretreatment agent (V) to the keratin fibers, (3) the pretreatment agent (V) applied in step (2) is allowed to act on the keratin fibres for a period of 1 to 45 minutes, preferably 5 to 30 minutes and particularly preferably 10 to 15 minutes, (4) if necessary, rinsing out the pretreatment agent (V) with water or with the aid of water and a shampoo, (5) if necessary, drying the keratin fibres, (6) Applying the colorant (F) to the keratin fibers, and (7) Action of the colorant (F) on the keratin fibers. Application of the after-treatment agent (N) as rinse-off or leave-on application

[0228] After applying or allowing the after-treatment product (N) or the colorant (F) to work, it can be rinsed out again in a subsequent step. Rinsing can be done with or without the aid of a shampoo or conditioner, for example.

[0229] Particularly good results were obtained, however, when the process according to the invention was designed as a leave-on process. This means that in this case, the after-treatment agent (N) or the coloring agent (F) was not rinsed out immediately after application, but rather the keratin fibers still coated with the agent (N) or (F) were dried. The drying of the keratin fibers can take place at room temperature or be assisted by an external heat source.

[0230] After the action in step (7), the colorant can therefore be rinsed out in step (8), or the keratin fibers can be dried without first rinsing out the agent (N) or (F).

[0231] In a further particularly preferred embodiment, a method according to the invention is characterized by the (8) Drying of the keratin fibers without prior washing out of the after-treatment agent (N) or the colorant (F).

[0232] In a further particularly preferred embodiment, a method according to the invention is characterized by the (8) Drying the keratin fibers without prior washing out of the after-treatment agent (N) or the coloring agent (F) at a temperature of 40 °C to 210 °C, preferably from 45 °C to 190 °C, more preferably from 45 °C to 170 °C, even more preferably from 45 °C to 150 °C and most preferably from 45 °C to 100 °C.

[0233] A drying heat treatment involves bringing the keratin fibers into contact with a heated device, or applying this heated device to or on the keratin material. Furthermore, the keratin fibers can also be exposed to warm / hot air for heat treatment. The device used can include a hairdryer, a blow dryer, a thermal cap, a flat iron, a curling iron, or an infrared lamp.

[0234] In a particularly preferred embodiment, a method according to the invention is characterized in that the heat treatment is carried out using a device which is heated to a temperature of 40 °C to 210 °C, preferably from 45 °C to 190 °C, more preferably from 45 °C to 170 °C, even more preferably from 45 °C to 100 °C.

[0235] Within the scope of a particularly preferred embodiment, a method according to the invention is characterized by drying the keratin fibers still treated with the aftertreatment agent (N) or the colorant (F), preferably drying the keratin fibers still treated with the aftertreatment agent (N) or the colorant (F) under the action of heat at a temperature of 40 °C to 210 °C, preferably from 40 °C to 190 °C, more preferably from 40 °C to 170 °C, even more preferably from 40 °C to 100 °C and most preferably from 40 °C to 80 °C.

[0236] For example, the keratin fibers or hair can be treated with a hairdryer that blows warm or hot air onto the keratin material. This air is preferably between 45 and 100°C, or even more preferably between 40 and 80°C. Alternatively, the keratin fibers or hair can be held under an infrared lamp, which is preferably set to a temperature of between 40 and 100°C. For heat treatment, hair can also be pressed between two appropriately temperature-controlled plates of a straightening iron, with the plates simultaneously moving along the fiber. The plates of the straightening iron can, for example, be set to a temperature of up to 210°C.

[0237] The duration of the heat treatment can be adapted to the selected temperature range. For example, a heat treatment can be carried out over a period of 5 seconds to 60 minutes, preferably from 15 seconds to 45 minutes, more preferably from 15 seconds to 30 minutes, and most preferably from 15 seconds to 15 minutes. Multi-component packaging unit (kit of parts)

[0238] To increase user convenience, all required resources are preferably provided to the user in the form of a multi-component packaging unit (kit of parts).

[0239] A second subject of the present invention is therefore a multi-component packaging unit (kit-of-parts) for treating keratin fibers, in particular human hair, comprising separately packaged - a first container with a pretreatment agent (V), and - a second container with a post-treatment agent (N), wherein the pre-treatment agent (V) and the post-treatment agent (N) were disclosed in detail in the description of the first subject matter of the invention.

[0240] A preferred embodiment comprises a multi-component packaging unit (kit-of-parts) for dyeing keratin fibers, in particular human hair, comprising separately packaged - a first container with a pretreatment agent (V), and - a second container with a colorant (F), wherein the pretreatment agent (V) and the colorant (F) were disclosed in detail in the description of the first subject matter of the invention.

[0241] Regarding the further preferred embodiments of the multi-component packaging units, what has been said about the method applies mutatis mutandis. Examples1. Formulations

[0242] The following formulations were prepared (unless otherwise stated, all data are in wt% active ingredient). Pretreatment agent (V) V1 (wt%) V2 (wt%) V3 (wt%) V4 (wt%) V5 (wt%) Cysteine - 10,0 - - - Acetylcysteine - - 10,0 - - Dithioerythritol - - - 10,0 - Dimercaptosuccinic acid - - - - 10,0 Monoethanolamine / Citric acid to pH 10 to pH 10 to pH 10 to pH 10 to pH 10 Water (distilled) to 100 to 100 to 100 to 100 to 100

[0243] The pretreatment agent (V1) does not contain a reducing agent.

[0244] The pretreatment agent (V2) contains the reducing agent cysteine, which is not according to the invention.

[0245] The pretreatment agents (V3), (V4) and (V5) each contain a reducing agent according to the invention, acetylcysteine, dithioerythritol or dimercaptosuccinic acid. Dye (F) Dye (F) % by weight (3-Aminopropyl)triethoxysilane 3,0 Methyltriethoxysilane 6,0 Water 1,0 NaOH 0,01 Unipure Red LC 3079 (Pigment Red 7, CAS No. 5281-04-9) 1,0 Ethanol to 100 2. Application

[0246] For the pre-wash, hair strands (Kerling 9-0) were pre-washed with Schauma 7 Herbal Shampoo. For this, 0.4 g of shampoo per 1 g strand was applied to each strand and the shampoo was massaged into the strands for 2 minutes. The strands were then rinsed with warm water for 30 seconds and dried.

[0247] The pre-treatment agent was applied to each of the pre-washed strands. 0.4 g of pre-treatment agent (V) was applied per 1 g of strand, massaged in, and left to work for 25 minutes at room temperature. The strands were then rinsed with warm water for 1 minute and dried.

[0248] Immediately afterward, each strand of hair was briefly moistened. The dye (F) was then applied to the towel-dried strand (1.0 g of dye (F) per 1 g of hair) and massaged into each strand for 30 seconds. Another 4 g of water was applied to the hair still coated with the dye, and the hair was massaged again. After a 5-minute exposure time, each strand of hair was dried with a hairdryer without rinsing out the dye (F).

[0249] The dyed strands were visually assessed by trained personnel under a daylight lamp. 3. Measurement of wash fastness

[0250] Following the coloring procedure, each colored strand was manually shampooed. For each wash, the strand was moistened, then a commercially available shampoo (Schwarzkopf, Schauma 7 Kräuter) was massaged into the strand for 25 seconds (0.25 g of shampoo per gram of hair). The strand was then rinsed with lukewarm tap water for 30 seconds and dried. After 4, 8, and 12 washes, each strand was visually assessed again under a daylight lamp.

[0251] The hair strands were assessed for their color intensity using a scale from 1 (very low color intensity) to 5 (very high color intensity). HW = hair washing 0 HW = Color result directly after coloring 0 HW 4 HW 8 HW 12 HW Pretreatment with (V1) Staining with (F) 5 3 2 1 Pretreatment with (V2) Staining with (F) 5 3 3 2 Pretreatment with (V3) Staining with (F) 5 5 4 3 Pretreatment with (V4) Staining with (F) 5 5 5 4 Pretreatment with (V5) Staining with (F) 5 4 3 3 Color intensity: 5 = very high 1 = very low

[0252] The best wash fastness properties were achieved with the successive application of the pretreatment agent (V4) and the dye (F).

[0253] Pretreatment with pretreatment agents (V3) and (V5) also provided improved wash fastness. 4. Measurement of wash fastness depending on the pH value of the pretreatment agent

[0254] The following pretreatment agents were prepared. Since the best results were achieved with pretreatment agent (V4), dithioerythritol was used as the reducing agent. V6 (wt%) V7 (wt%) V8 (wt%) Cysteine --- --- --- Acetylcysteine --- --- --- Dithioerythritol 5,0 5,0 5,0 Dimercaptosuccinic acid --- --- --- Monoethanolamine / Citric acid to pH 10 to pH 7 to pH 3 Water (distilled) to 100 to 100 to 100

[0255] The pretreatment agents (V) and the dye (F) were applied to hair strands as described in point 2. The hair strands were then washed as described in point 3, and the washfastness was determined. HW = hair washing 0 HW = Color result directly after coloring 0 HW 4 HW 8 HW 12 HW Pretreatment with (V6) Staining with (F) 5 5 4 4 Pretreatment with (V7) Staining with (F) 4 4 3 3 Pretreatment with (V8) Staining with (F) 4 3 3 3 Color intensity: 5 = very high 1 = very low

[0256] The best wash fastnesses were obtained with the pretreatment agent (V6) adjusted to a pH of 10. 5. Measurement of wash-out behavior on hair strands with different degrees of damage

[0257] The following pretreatment agents were produced: Pretreatment agent (V) V1 (wt%) V6 (wt%) V9 (wt%) Cysteine - - - Acetylcysteine - --- Dithioerythritol - 5,0 1,0 Dimercaptosuccinic acid - - - Monoethanolamine / Citric acid to pH 10 to pH 10 to pH 10 Water (distilled) to 100 to 100 to 100

[0258] Hair strands with varying degrees of damage (Kerling 9-0, slightly damaged, and Euronaturhaar white, heavily bleached, and heavily damaged) were pre-washed with Schauma 7 Herbal Shampoo. For this, 0.4 g of shampoo per 1 g of strand was applied to each strand and the shampoo was massaged into the strands for 2 minutes. The strands were then rinsed with warm water for 30 seconds and dried.

[0259] The pretreatment agent was applied to each of the pre-washed strands. 1.0 g of pretreatment agent (V) was applied per 1 g of strand, massaged in, and left to work for 25 minutes at room temperature. The strands were then rinsed with warm water for 1 minute and dried.

[0260] Immediately afterward, each strand of hair was briefly moistened. The dye (F) was applied to the towel-dried strand (1.0 g of dye (F) per 1 g of hair) and massaged into each strand for 30 seconds. Another 4 g of water was applied to the hair still coated with the dye, and the hair was massaged again. After a 5-minute exposure time, each strand of hair was dried with a hairdryer without rinsing out the dye (F). K = Kerling 9-0 (little damage) ENH = Euronatural hair white (severely damaged) 0 HW 4 HW 8 HW 12 HW ENH K ENH K ENH K ENH K Pretreatment with (V1) Staining with (F) 5 5 4 3 4 2 3 1 Pretreatment with (V6) Staining with (F) 5 5 5 5 4 4 4 4 Pretreatment with (V9) Staining with (F) 5 5 4 4 4 3 3 3

[0261] Pretreatment with pretreatment agent (V1) (without reducing agent) resulted in significantly different washfastnesses when applied to strands with varying degrees of damage. On severely damaged strands (ENH), better washfastness was observed with the combination (V1) / (F) than on less severely damaged strands (K). This undesirable effect could be counteracted by using a pretreatment agent containing dithioerythritol (5.0 wt.% (V6) or 1.0 wt.% (V9)). Pretreatment with (V6) and (V9) improved washfastnesses on both strand types and also led to a more uniform color result after shampooing. This effect was even more pronounced for the combination (V6) / (F) (pretreatment with 5.0 wt.% dithioerythritol) than for the combination (V9) / (F) (pretreatment with 1.0 wt.% dithioerythritol). QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 2168633 B1 [0008, 0009] WO 2022 / 184357 A1

[0010]

Claims

[1] Method for treating keratin fibres, in particular human hair, comprising the following steps: - Application of a pretreatment agent (V) to the keratin fibers, wherein the pretreatment agent contains (V-1) at least one reducing agent selected from the group consisting of dithioerythritol, dithiothreitol, acetylcysteine, dimercaptosuccinic acid, thioglycerol, thiolactic acid, sodium dithionite, zinc dithionite, potassium dithionite, formamidine sulfinic acid, 2-hydroxy-2-sulfinoacetic acid and salts thereof, and - Application of a post-treatment agent (N) to the keratin fibers, wherein the post-treatment agent (N) contains (N-1) at least one organic silicon compound from the group of silanes with one, two or three silicon atoms. [2] Method according to claim 1, characterized bythat the pretreatment agent (V) - based on the total weight of the pretreatment agent (V) - contains one or more reducing agents (V-1), preferably dithioerythritol, dithiothreitol, acetylcysteine and / or salts thereof, particularly preferably dithioerythritol and / or dithiothreitol, in a total amount of 0.1 to 15.0 wt.%, preferably 0.2 to 10.5 wt.%, further preferably 0.3 to 7.5 wt.% and very particularly preferably 0.5 to 5.5 wt.%. [3] Method according to one of claims 1 to 2, characterized by that the pretreatment agent (V) contains water and has a pH of 7.0 to 12.0, preferably of 7.5 to 11.5, more preferably of 8.0 to 11.0 and particularly preferably of 8.5 to 10.

5. [4] Method according to one of claims 1 to 3, characterized by that the aftertreatment agent (N) contains at least one silane (N-1) of formula (I) and / or its hydrolysis and / or condensation products R1R2N-L-Si(OR3)a(R4) b(I), where - R1, R2 independently represent a hydrogen atom or a C1-C6 alkyl group, - L for a linear or branched, divalent C1-C 20 -alkylene group, - R3, R4 independently represent a C1-C6 alkyl group, - a, stands for an integer from 1 to 3, and - b stands for the integer 3 - a. [5] Method according to one of claims 1 to 4, characterized by that the aftertreatment agent (N) contains at least one silane (N-1) selected from the group consisting of - (3-Aminopropyl)triethoxysilane - (3-Aminopropyl)trimethoxysilane - (2-Aminoethyl)triethoxysilane - (2-Aminoethyl)trimethoxysilane - (3-Dimethylaminopropyl)triethoxysilane - (3-Dimethylaminopropyl)trimethoxysilane - (2-Dimethylaminoethyl)triethoxysilane. - (2-Dimethylaminoethyl)trimethoxysilane and / or their hydrolysis and / or condensation products. [6] Method according to one of claims 1 to 5, characterized by that the aftertreatment agent (N) contains at least one silane (N-1) of formula (II) and / or its hydrolysis and / or condensation products, R5Si(OR6) k (R7) m (II), where - R5 for a C1-C 18 -alkyl group, - R6 represents a hydrogen atom or a C1-C6 alkyl group, - R7 represents a C1-C6 alkyl group - k is an integer from 1 to 3, and - m stands for the integer 3 - k. [7] Method according to one of claims 1 to 6, characterized by that the aftertreatment agent (N) contains at least one silane (N-1) selected from the group consisting of - Methyltrimethoxysilane - Methyltriethoxysilane - Ethyltrimethoxysilane - Ethyltriethoxysilane - Propyltrimethoxysilane - Propyltriethoxysilane - Hexyltrimethoxysilane - Hexyltriethoxysilane - Octyltrimethoxysilane - Octyltriethoxysilane - Dodecyltrimethoxysilane, - Dodecyltriethoxysilane, - Octadecyltrimethoxysilane, - Octadecyltriethoxysilane and / or their hydrolysis and / or condensation products. [8] Method according to one of claims 1 to 7, characterized by that the aftertreatment agent (N) contains one or more solvents from the group consisting of ethanol, poly-C1-C6-alkylene glycols, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, dipropylene glycol, ethanol, isopropanol, diethylene glycol monoethyl ether, glycerol, phenoxyethanol and benzyl alcohol. [9] Method according to one of claims 1 to 8, characterized bythat the aftertreatment agent (N) - based on the total weight of the aftertreatment agent (N) - contains one or more solvents, preferably ethanol and / or poly-C1-C6-alkylene glycols, in a total amount of 10.0 to 99.0 wt.%, preferably 30.0 to 99.0 wt.%, more preferably 50.0 to 99.0 wt.% and most preferably 70.0 to 99.0 wt.%. [10] Method according to one of claims 1 to 9, characterized by that the aftertreatment agent (N) - based on the total weight of the aftertreatment agent (N) - contains 0 to 20.0 wt.%, preferably from 0.1 to 10.0 wt.%, more preferably from 0.1 to 5.0 wt.%, and particularly preferably from 0.5 to 3.0 wt.% of water. [11] Method according to one of claims 1 to 10, characterized bythat it is a process for dyeing keratin fibers, in particular human hair, and that the after-treatment agent (N) is a colorant (F) which contains at least one color-providing compound from the group of pigments and direct dyes. [12] Method according to one of claims 1 to 11, comprising the steps in the order given: - if necessary, application of a pre-shampoo on the keratin fibers, then - Application of the pre-treatment agent (V) on the keratin fibers, then - Application of the post-treatment agent (N) to the keratin fibers, wherein between the application of the pre-treatment agent (V) and the application of the post-treatment agent (N) there is a period of maximum 24 hours, preferably of maximum 12 hours, more preferably of maximum 6 hours and most preferably of maximum 3 hours. [13] A method according to any one of claims 1 to 12, comprising the following steps in the order given: (1) if necessary, washing the keratin fibers with a pre-shampoo, (2) Applying the pretreatment agent (V) to the keratin fibers, (3) Allowing the pretreatment agent (V) applied in step (2) to act on the keratin fibres for a period of 1 to 45 minutes, preferably 5 to 30 minutes, (4) if necessary, rinsing out the pretreatment agent (V) with water or with the aid of water and a shampoo, (5) if necessary, drying the keratin fibres, (6) Applying the after-treatment agent (N), preferably the coloring agent (F), to the keratin fibers, and (7) Action of the after-treatment agent (N), preferably the colorant (F), on the keratin fibers. [14] Method according to claim 13, characterized by the (8) Drying the keratin fibers without prior washing out of the after-treatment agent (N), preferably the colorant (F). [15] Multi-component packaging unit (kit-of-parts) for treating keratin fibers, in particular human hair, comprising separately packaged - a first container with a pretreatment agent (V), and - a second container with a post-treatment agent (N), wherein the pre-treatment agent (V) and the post-treatment agent (N) were defined in claims 1 to 11.