Natural-substance-based hair-dyeing methods

Abstract

The invention relates to methods for dyeing keratin-containing fibers, in particular human hair, using plant polyphenols at a pH value in the range of 1.0-6.9 and / or with a content of at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, and subsequent treatment with one or more silver salts. The invention also relates to products and kits for carrying out these dyeing methods.

Description

[0001] Natural substance-based hair coloring processes

[0002] The invention relates to methods for dyeing keratin-containing fibers, in particular human hair, using plant polyphenols at a pH value in the range of 1.0 to 6.9 and / or at a content of at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, and subsequent treatment with one or more silver salts, as well as agents and kits for carrying out these dyeing methods.

[0003] The desire to change one's hair color is a strong need for many consumers. To satisfy this need, the cosmetic industry offers a diverse range of products. Hair dyes that achieve particularly long-lasting color with high coverage are usually oxidative dyes. These use oxidizing agents that can damage the hair structure. Certain cationic direct-acting azo dyes are also capable of achieving hair color changes with excellent colorfastness. However, these azo dyes are synthetic dyes.

[0004] A growing number of consumers desire hair dyes and hair coloring processes based on natural dyes, even though these products and processes are often inferior to the aforementioned products and processes in terms of authenticity, coverage, and color variety.

[0005] State of the art

[0006] Besides dyeing with henna, which is obtained from the plant Lawsonia inermis, dyeing hair with plant parts of Camellia sinensis, in particular with the leaves of Camellia sinensis, is also already known (see KR20090056479A). With the dyeing processes known in the prior art using metal salts or with plant parts of Camellia sinensis, only a black color is usually achieved.

[0007] The use of salts of certain transition metals, particularly silver salts, for natural hair coloring is also known in the prior art; see JP2013001673A, KR20150027578A, or EP327345A2. JP2014051479A describes a method for producing a hair coloring product using silver salts in combination with citric acid or comparable organic carboxylic acids. The reduction to metallic silver, resulting in a red color, and treatment with UV / VIS light are mentioned. The reduction reaction of silver is explained here by irradiation with light. The addition of a plant polyphenol is not disclosed. The addition of halides or pseudohalides is also not mentioned, and the use of hydrochloric acid is deliberately avoided due to the potential precipitation of silver chloride.In IN421240 B, a two-step process is described using various reducing agents, including citrate, ascorbic acid, or tartrate, a base, and silver salts. The treatment sequence involves first applying the silver salt with / without a base, followed by treatment with the reducing agent (and base). The phenomenon of in-situ nanoparticle generation is described. The observed colors, particularly at concentrations >0.5% of the reducing agent, are described as dark to intense black. Irradiation with light is not mentioned; the strands undergo heat treatment between 75 and 100 °C. Documents DE2806603A1 and US9125842B2 each disclose a two-step hair coloring process in which a plant polyphenol is first applied to the hair, followed by an ammoniacal silver salt solution.The addition of halides or pseudohalides is not disclosed.

[0008] Task

[0009] The present invention was based on the objective of providing a method for dyeing keratin-containing fibers, in particular human hair, using naturally occurring substances with which a wider range of colorations can be achieved.

[0010] Surprisingly, it was found that with the dyeing processes and kits described in the patent claims, using plant polyphenols at a pH value in the range of 1.0 to 6.9 and / or at a content of at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, and subsequent treatment with one or more silver salts, dyeings with a wider variety of colors can be achieved.

[0011] A first object of the present invention is therefore a method for the non-oxidative coloring of keratinous fibers, in particular human hair, comprising the following process steps in the specified order: i. providing a composition C containing at least one polyphenol of plant origin in a cosmetic carrier, ii. applying the composition C to the keratin fibers to be colored, iii. allowing the composition C to act for a period of 1 to 60 minutes, iv. rinsing off the composition C, v. optionally drying the keratin fibers, vi. subsequently treating the keratin fibers with a composition S, which is an aqueous solution of a silver salt, for a period of 0.5 to 60 minutes, vii. rinsing off the silver salt-containing composition S, and viii.optional washing and / or drying of the keratin fibers, wherein no oxidizing agents other than atmospheric oxygen are used in the process, characterized in that the composition C has at least one feature M selected from

[0012] M1) a pH value in the range of 1.0 to 6.9, measured at 20°C, and

[0013] M2) containing at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, wherein, if only feature M1) is realized and not feature M2), at least one polyphenol of plant origin is not derived from Camellia sinensis and the silver salt-containing composition S is ammonia-free.

[0014] Effects of electromagnetic radiation on hair treated with plant polyphenols and silver salts

[0015] Preferred dyeing processes according to the invention are characterized in that the keratin fibers are exposed to electromagnetic radiation following process step vii. or process step viii. Preferably, this radiation exposure lasts 0.5 to 60 minutes, particularly preferably 1 to 45 minutes, extremely preferably 5 to 30 minutes, and further extremely preferably 10 to 20 minutes.

[0016] A preferred electromagnetic radiation according to the invention, to which the keratin fibers treated with plant polyphenol at a pH value in the range of 1.0 to 6.9 and / or at a content of at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, and subsequently with silver salt, are exposed in the optional step (ix) of the process according to the invention, is UV / VIS radiation, particularly preferably UV / VIS radiation in the wavelength range of 200 to 800 nm, and most preferably in the wavelength range of 290 to 700 nm.

[0017] Preferred dyeing processes according to the invention are characterized in that, following process step vii. or process step viii., the keratin fibers are exposed in a process step (ix) for a period of 0.5 to 60 minutes, preferably 1 to 45 minutes, particularly preferably 5 to 30 minutes, and most preferably 10 to 20 minutes, to electromagnetic radiation, preferably selected from UV / VIS radiation in the wavelength range of 200 to 800 nm. UV / VIS radiation comprises, as electromagnetic radiation in the wavelength range of 200 nm to 800 nm, the UV range (ultraviolet range) and the VIS range (visible range).

[0018] UV radiation (ultraviolet radiation) consists of electromagnetic waves with a wavelength of 380 to 10 nm or a frequency of approximately 790 THz to 30 PHz. The energy of a single photon ranges from approximately 3.3 eV (380 nm) to approximately 124 eV (10 nm).

[0019] Visible light, as perceived by the human eye, is the part of the electromagnetic spectrum with wavelengths between approximately 380 and 780 nm. Light with a wavelength of 800 nm is just barely visible.

[0020] Exposure to electromagnetic radiation within the meaning of the invention refers, on the one hand, to exposure to radiation from a natural radiation source, and on the other hand, to irradiation with an artificial light source which emits electromagnetic radiation in the desired wavelength range.

[0021] The exposure of keratin fibers treated with plant polyphenol at a pH value in the range of 1.0 to 6.9 and / or at a content of at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, and subsequently with silver salt, to daylight is also to be understood as exposure to electromagnetic radiation or irradiation within the meaning of the invention.

[0022] In the dyeing process preferred according to the invention, the keratin fibers to be treated are successively treated first with at least one plant polyphenol at a pH value in the range of 1.0 to 6.9 and / or with a content of at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, and then with a silver salt and rinsed with water. It is preferred that the keratin fibers are dried after the last rinsing step, preferably first with a towel, then optionally with a hairdryer or a hair dryer, or left to air dry. Particularly preferred dyeing processes according to the invention are characterized in that, after completion of process step viii, the keratin fibers have a water content of 1–42 wt.%, preferably 3–30 wt.%, particularly preferably 5–25 wt.%, and most preferably 8–15 wt.%, based on their weight.They contain -% water. After the optional drying step, the keratin fibers are exposed to electromagnetic radiation.

[0023] The source of this electromagnetic radiation can be artificial or natural. The artificial or natural electromagnetic radiation can be continuous or discontinuous. Preferably, the electromagnetic radiation used is light radiation in the wavelength range of 200 nm to 800 nm. For the purposes of the present invention, the term "artificial light radiation" means light radiation that differs from natural daylight, that is, light produced by the sun. In other words, natural daylight, that is, light produced by the sun, is not artificial light radiation.

[0024] The term "natural light radiation" means radiation whose only light source is daylight produced by the sun.

[0025] Preferably, the hair is irradiated with natural light radiation at a wavelength in the range of 360 to 600 nm, preferably in the range of 375 to 550 nm, particularly preferably in the range of 400 to 480 nm.

[0026] Irradiation of the hair with artificial light radiation at a wavelength in the range of 360 to 600 nm, preferably in the range of 375 to 550 nm, and particularly preferably in the range of 400 to 480 nm, is also preferred.

[0027] Preferably, the natural light radiation used has an energy level per unit area of ​​up to or equal to 1 J / cm². 2 , preferably greater than 1 J / cm² 2 , even more preferably in the range of 1.001 and 100 J / cm² 2 , even more preferably in the range of 2 to 50 J / cm² 2 , especially preferred in the range of 3 to 10 J / cm² 2 on.

[0028] Preferably, the artificial light radiation used has an energy quantity per unit area of ​​up to or equal to 1 J / cm². 2 , preferably greater than 1 J / cm² 2 , even more preferably in the range of 1.001 and 100 J / cm² 2 , even more preferably in the range of 2 to 50 J / cm² 2 , especially preferred in the range of 3 to 10 J / cm² 2 on.

[0029] Preferably, the natural light radiation used has a luminous efficacy of 50 to 100 Im / W (lumens per watt), preferably 70 to 85 Im / W.

[0030] Preferably, the artificial light radiation used has a luminous efficacy of 50 to 100 Im / W (lumens per watt), preferably 70 to 85 Im / W.

[0031] Preferably, the natural light radiation used has a luminous flux of 50 to 100 Im / W (lumens per watt), preferably 70 to 85 Im / W.

[0032] Preferably, the artificial light radiation used has a luminous flux of 3500 to 8000 lumens, preferably of 4000 to 6000 lumens.

[0033] Preferably, the artificial light radiation is generated using a device selected from arc lamps such as xenon lamps and mercury lamps, fluorescent lamps, incandescent lamps such as halogen lamps, light-emitting diodes (LEDs), organic light-emitting diodes (OLEDs) and lasers.

[0034] Examples include Golite BLU products from Philips, the Energylight HF 3319 / 01 lamp from Philips, the Dayvia White and Messa lamps from Solvital, the Lumino Plus lamp from Laanaform, the Medibeam lamp from Medibeam, the M-LED 01 lamp from Meimed, the Lifemax Light Pod lamp from Lifemax, the Lite-Pad lamp from Reicorp, the Omnilux Clear-U and New-U lamps from Omnilux, the 1000 W xenon arc lamp from Lot-Oriel and the Camag Box 3 (4x8 W) lamp from Camag. In a first embodiment, the dyeing process according to the invention is characterized in that the composition C, which contains at least one plant polyphenol, has a pH value of 1.0 to 6.9, preferably 2.5 to 6.0, particularly preferably 3.0 to 5.5, and more preferably 3.0 to 4.9, each measured at 20°C, hereinafter referred to as feature M1.

[0035] In a second embodiment, the dyeing process according to the invention is characterized in that the composition C, which contains at least one plant polyphenol, additionally contains at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, hereinafter referred to as feature M2. In this (pseudo-)halide-containing embodiment, the composition C preferably has a pH value of 1.0 to 11.0, more preferably of 2.5 to 9.0, particularly preferably of 3.0 to 8.0, more preferably of 3.0 to > 6.9, and most preferably of 3.5 to 6.9, and most preferably of 4.0 to 5.5, in each case measured at 20°C.

[0036] Preferred compositions C according to the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one plant polyphenol, additionally contains at least one salt, selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, in a total amount of 0.1 to 10.0 wt.%, preferably 0.5 to 7.0 wt.%, particularly preferably 1.0 to 6.0 wt.%, extraordinarily preferably 2.5 to 5.0 wt.%, further extraordinarily preferably 3.0 to 4.0 wt.%, in each case based on the weight of the composition C.

[0037] Preferred compositions C according to the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one plant polyphenol, additionally contains one or more salts selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudo-halide anion, which are selected from sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, lithium fluoride, lithium chloride, lithium bromide, lithium iodide, rubidium fluoride, rubidium chloride, rubidium bromide, rubidium iodide, ammonium thiocyanate (NH4SCN), sodium thiocyanate (NaSCN) and potassium thiocyanate (KSCN) as well as mixtures of the aforementioned salts.Particularly preferred salts according to the invention are selected from sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, ammonium thiocyanate, sodium thiocyanate, and potassium thiocyanate, as well as mixtures of the aforementioned salts. Extraordinarily preferred salts according to the invention are selected from sodium chloride, sodium bromide, sodium iodide, potassium chloride, potassium bromide, potassium iodide, ammonium chloride, ammonium bromide, ammonium iodide, and ammonium thiocyanate, as well as mixtures of the aforementioned salts.Further particularly preferred compositions C according to the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one vegetable polyphenol, additionally contains one or more salts selected from sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, lithium fluoride, lithium chloride, lithium bromide, lithium iodide, rubidium fluoride, rubidium chloride, rubidium bromide, rubidium iodide, ammonium thiocyanate, sodium thiocyanate and potassium thiocyanate, as well as mixtures of the aforementioned salts, in a total amount of 0.1 to 10.0 wt.%, preferably 0.5 to 7.0 wt.%, particularly preferably 1.0 to 6.0 wt.%, extremely preferably 2.5 to 5.0 wt.%, and further extremely preferably 3.0 to 4.0 wt.%, respectively. on the weight of composition C.

[0038] Further particularly preferred compositions C according to the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one vegetable polyphenol, additionally contains one or more salts selected from sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, ammonium thiocyanate, sodium thiocyanate and potassium thiocyanate, as well as mixtures of the aforementioned salts, in a total amount of 0.1 to 10.0 wt.%, preferably 0.5 to 7.0 wt.%, particularly preferably 1.0 to 6.0 wt.%, extraordinarily preferably 2.5 to 5.0 wt.%, further extraordinarily preferably 3.0 to 4.0 wt.%, in each case based on the weight of the composition C.

[0039] Further particularly preferred compositions C according to the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one vegetable polyphenol, additionally contains one or more salts selected from sodium chloride, sodium bromide, sodium iodide, potassium chloride, potassium bromide, potassium iodide, ammonium chloride, ammonium bromide, ammonium iodide and ammonium thiocyanate as well as mixtures of the aforementioned salts, in a total amount of 0.1 to 10.0 wt.%, preferably 0.5 to 7.0 wt.%, particularly preferably 1.0 to 6.0 wt.%, extraordinarily preferably 2.5 to 5.0 wt.%, further extraordinarily preferably 3.0 to 4.0 wt.%, in each case based on the weight of the composition C.

[0040] Further preferred compositions C according to the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one plant polyphenol, additionally contains at least one salt, selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, in a total amount of 0.1 to 10.0 wt.%, preferably 0.5 to 7.0 wt.%, particularly preferably 1.0 to 6.0 wt.%, extremely preferably 2.5 to 5.0 wt.%, further extremely preferably 3.0 to 4.0 wt.%, in each case based on the weight of the composition C, and a pH value of 1.0 to 11.0, further preferably 2.5 to 9.0, particularly preferably 3.0 to 8.0, further particularly preferably 3.0 to > 6.9, extremely preferably 3.5 to 6.9, further extremely preferably 4.0 to 5.5. each measured at 20°C.

[0041] Preferred compositions C according to the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one plant polyphenol, additionally contains one or more salts selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudo-halide anion, which are selected from sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, lithium fluoride, lithium chloride, lithium bromide, lithium iodide, rubidium fluoride, rubidium chloride, rubidium bromide, rubidium iodide, ammonium thiocyanate (NH4SCN), sodium thiocyanate (NaSCN) and potassium thiocyanate (KSCN) as well as mixtures of the aforementioned salts.Particularly preferred salts according to the invention are selected from sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, ammonium thiocyanate, sodium thiocyanate, and potassium thiocyanate, as well as mixtures of the aforementioned salts. Extraordinarily preferred salts according to the invention are selected from sodium chloride, sodium bromide, sodium iodide, potassium chloride, potassium bromide, potassium iodide, ammonium chloride, ammonium bromide, ammonium iodide, and ammonium thiocyanate, as well as mixtures of the aforementioned salts.Further compositions C preferred according to the invention in the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one plant polyphenol, additionally contains one or more salts selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, and has a pH value of 1.0 to 11.0, more preferably 2.5 to 9.0, particularly preferably 3.0 to 8.0, more preferably 3.0 to > 6.9, more preferably 3.5 to 6.9, more preferably 4.0 to 5.5, each measured at 20°C.

[0042] Further particularly preferred compositions C according to the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one vegetable polyphenol, additionally comprises one or more salts selected from sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, lithium fluoride, lithium chloride, lithium bromide, lithium iodide, rubidium fluoride, rubidium chloride, rubidium bromide, rubidium iodide, ammonium thiocyanate, sodium thiocyanate and potassium thiocyanate, as well as mixtures of the aforementioned salts, in a total amount of 0.1 to 10.0 wt.%, preferably 0.5 to 7.0 wt.%, particularly preferably 1.0 to 6.0 wt.%, extremely preferably 2.5 to 5.0 wt.%, further extremely preferably 3.0 to 4.0 wt.%.-% contained, each based on the weight of composition C, and having a pH value of 1.0 to 11.0, more preferably 2.5 to 9.0, particularly preferably 3.0 to 8.0, more preferably 3.0 to > 6.9, extraordinarily preferably 3.5 to 6.9, more preferably 4.0 to 5.5, each measured at 20°C.

[0043] Further particularly preferred compositions C according to the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one vegetable polyphenol, additionally comprises one or more salts selected from sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, ammonium thiocyanate, sodium thiocyanate and potassium thiocyanate, as well as mixtures of the aforementioned salts, in a total amount of 0.1 to 10.0 wt.%, preferably 0.5 to 7.0 wt.%, particularly preferably 1.0 to 6.0 wt.%, extremely preferably 2.5 to 5.0 wt.%, and further extremely preferably 3.0 to 4.0 wt.%.-%, contained, each based on the weight of composition C, and having a pH value of 1.0 to 11.0, more preferably 2.5 to 9.0, particularly preferably 3.0 to 8.0, more preferably 3.0 to > 6.9, extraordinarily preferably 3.5 to 6.9, more preferably 4.0 to 5.5, each measured at 20°C.

[0044] Further particularly preferred compositions C according to the second embodiment of the dyeing process according to the invention are characterized in that the composition C, which contains at least one plant polyphenol, additionally comprises one or more salts selected from sodium chloride, sodium bromide, sodium iodide, potassium chloride, potassium bromide, potassium iodide, ammonium chloride, ammonium bromide, ammonium iodide and ammonium thiocyanate, as well as mixtures of the aforementioned salts, in a total amount of 0.1 to 10.0 wt.%, preferably 0.5 to 7.0 wt.%, particularly preferably 1.0 to 6.0 wt.%, extraordinarily preferably 2.5 to 5.0 wt.%, and further extraordinarily preferably 3.0 to 4.0 wt.%.-%, contained, each based on the weight of composition C, and having a pH value of 1.0 to 11.0, more preferably from 2.5 to 9.0, particularly preferably from 3.0 to 8.0, more preferably from 3.0 to > 6.9, extraordinarily preferably from 3.5 to 6.9, more preferably from 4.0 to 5.5, each measured at 20°C.

[0045] Plant polyphenols

[0046] According to the invention, plant polyphenols are understood to be those polyphenols which

[0047] - are available via the shikimat biosynthesis pathway and

[0048] - have at least 2 hydroxy groups in the molecule and

[0049] - have a molar mass in the range of 170 to 20,000 g / mol. The plant polyphenols used according to the invention, or "plant-derived polyphenols," do not necessarily have to be obtained from a plant, for example, by extraction. They can just as well be obtained by a biotechnological production process in which, in particular, bacteria, yeasts, or fungi produce the polyphenol, which is obtainable via the shikimate biosynthesis pathway and has at least two hydroxyl groups in the molecule and a molar mass in the range of 170 to 20,000 g / mol. Corresponding processes for the production of plant polyphenols or plant-derived polyphenols are known in the prior art, for example, from US20230313246A1 or JP2022038951A. Petrochemically synthesized polyphenols of plant origin are also included within the scope of the present invention.

[0050] According to the invention, preferred dyeing processes, compositions C and dyeing kits are characterized in that the at least one plant polyphenol is selected from tannins and pseudotannins as well as mixtures thereof.

[0051] Tannins are phytochemical products of secondary metabolism, more precisely, of the shikimate biosynthesis pathway, in plants. They can be obtained from various plant parts, preferably from wood, especially stem wood, but also from bark, leaves, seeds, fruits, galls, pods, legumes, or roots.

[0052] According to the invention, the tannins preferably used are selected from hydrolyzable tannins and condensed tannins.

[0053] Hydrolyzable tannins have gallic acid as their basic building block. Gallic acid (170.12 g / mol) itself is not called a tannin, but a pseudotannin.

[0054] Hydrolyzable tannins can be divided into gallotannins and ellagitannins. Gallotannin is also known as tannic acid.

[0055] Condensed tannins have flavan-3-ols as their basic building blocks. Flavan-3-ols (226.27 g / mol) themselves are not referred to as tannins, but as pseudotannins. Preferred condensed tannins include, for example, proanthocyanidins, procyanidins, flavonoids, propelargonidins, prodelphinides, profisetinidines, proteracacinidins, proguibourtinidines, and prorobinetidines. Among the flavonoids, luteolin, apigenin, kaempferol, and chrysoeriol—that is, the main flavonoids from Reseda luteola—are particularly preferred according to the invention.

[0056] Preferred pseudotannins used according to the invention include gallic acid, flavan-3-ols and chlorogenic acid.

[0057] Preferred dyeing processes according to the invention are characterized in that the at least one plant polyphenol, preferably selected from tannins and pseudotannins, is obtained from at least one plant selected from Reseda spp., in particular Reseda luteola, Camellia sinensis, Acacia spp., in particular Acacia mollissima, Acacia negra and Acacia dealbata, Olea europaea (olive tree), Schinopsis lorentzii, Aspidosperma quebracho-blanco, Rubiaceae, Coffea arabica L., Rheum spp., in particular Rheum palmatum, Pinus spp., Picea spp., Vitis vinifera, Lawsonia inermis (red henna), Quercus spp. (oak), in particular Quercus macrolepsis, Curcuma longa, Juglans spp., in particular Juglans nigra and Juglans regia, the tara tree (Tara spinosa, Cesalpinia spinosa, Caesalpinia tinctoria), horse chestnut (Castanea sativa), ginseng (Rhus coriaria), smoke tree (Rhus cotinus, Cotinus coggygria), Haematoxylum brasiletto L. (Brazilian bloodwood tree), Haematoxylum campechianum (bloodwood tree, logwood tree, Campeche tree), and Madura tinctoria (dyer's mulberry tree), as well as mixtures thereof. According to the invention, the at least one plant polyphenol is particularly preferred if selected from polyphenols derived from Reseda luteola.

[0058] If the composition C according to the invention only realizes feature M1) according to which it has a pH value of 1.0 to 6.9, measured at 20°C, and no salt according to feature M2) is contained in C, the at least one polyphenol of plant origin does not originate from Camellia sinensis.

[0059] Further dyeing processes preferred according to the invention are characterized in that the at least one polyphenol, which is preferably selected from tannins and pseudotannins, is present in the form of at least one ground plant part. Plant parts preferred according to the invention, which can preferably be used in ground form, are leaves, flowers, branches, fruit peels, seed coats, rhizomes (rootstocks), and roots.

[0060] Further dyeing processes preferred according to the invention are characterized in that the at least one polyphenol, preferably selected from tannins and pseudotannins, is present in the form of at least one plant part extract. Plant parts preferred according to the invention, from which extracts preferred according to the invention can be obtained, are branches, flowers, the trunk wood, the heartwood, as well as bark, leaves, seeds, fruits, galls, pods, husks, and roots. Suitable extraction agents are water, in particular hot water with a temperature of 45 - 100 °C, furthermore Ci-C4 alkanols and C2-C4 polyols, in particular ethanol, isopropanol, n-propanol, ethylene glycol, 1,2-propanediol, glycerol and 1,3-butylene glycol, as well as mixtures of these extraction agents, in particular mixtures of water and at least one Ci-C4 alkanol, mixtures of water and at least one C2-C4 polyol, particularly preferably water / ethanol mixtures.

[0061] According to the invention, particularly preferred plant polyphenols are contained as a dried extract from the aerial parts of Reseda luteola, especially from the upper flowering branches and flowers. Preferably used as extraction agents for Reseda luteola are water, mixtures of water and at least one C₂-C₄ alkanol, mixtures of water and at least one C₂-C₄ polyol, and particularly preferably water / ethanol mixtures. According to the invention, preferred staining processes are characterized in that the at least one plant polyphenol is contained in a total amount of 0.1–50 wt.%, preferably 0.5–20 wt.%, particularly preferably 0.8–10 wt.%, and most preferably 1–2 wt.%, based on the weight of composition C. According to the invention, particularly preferred staining processes are characterized in that at least one plant polyphenol from Reseda luteola is contained in a total amount of 0.1–50 wt.%, preferably 0.5–20 wt.%.-%, particularly preferably 0.8 - 10 wt.%, extraordinarily preferably 1 - 2 wt.%, based on the weight of composition C, is contained.

[0062] Preferred dyeing processes according to the invention are characterized in that the at least one silver salt with which the keratin fibers are treated after treatment with the plant polyphenol-containing composition C is selected from silver nitrate, silver sulfate, silver citrate, silver dihydrogen citrate, silver lactate, silver acetate, silver malate, silver succinate, silver tartrate, silver almondate, silver salicylate, silver gluconate, silver adipate, and silver galactarate, as well as from mixtures of these salts. Particularly preferred silver salts according to the invention are selected from silver nitrate, silver sulfate, silver citrate, silver dihydrogen citrate, and silver lactate, as well as mixtures of these salts. Silver nitrate is particularly preferred according to the invention.

[0063] Particularly preferred dyeing processes according to the invention are characterized in that the at least one silver salt is contained in a total amount of 0.05 - 2 wt.%, preferably 0.1 - 1.0 wt.%, particularly preferably 0.2 - 0.8 wt.%, and most preferably 0.3 - 0.5 wt.%, in each case based on the weight of the composition S.

[0064] According to the invention, the most preferred dyeing processes are characterized in that the at least one silver salt is contained in a total amount of 0.05 - 2 wt.%, preferably 0.1 - 1.0 wt.%, particularly preferably 0.2 - 0.8 wt.%, and most preferably 0.3 - 0.5 wt.%, based on the weight of the composition S, wherein the silver salt is selected from silver nitrate, silver sulfate, silver citrate, silver dihydrogen citrate, silver lactate, silver acetate, silver malate, silver succinate, silver tartrate, silver almondate, silver salicylate, silver gluconate, silver adipate and silver galactarate, as well as from mixtures of these salts.

[0065] Further dyeing processes that are particularly preferred according to the invention are characterized in that the at least one silver salt is contained in a total amount of 0.05–2 wt.%, preferably 0.1–1.0 wt.%, particularly preferably 0.2–0.8 wt.%, and most preferably 0.3–0.5 wt.%, in each case based on the weight of the composition S, wherein the silver salt is selected from silver nitrate, silver sulfate, silver citrate, silver dihydrogen citrate, and silver lactate, as well as from mixtures of these salts. Further dyeing processes that are particularly preferred according to the invention are characterized in that the silver salt-containing composition S has a pH value of 2.0 to 8.0, preferably 3.0 to 7.5, particularly preferably 4.0 to 7.0, and most preferably 4.5 to 6.5, in each case measured at 20°C.

[0066] In a preferred embodiment of the dyeing process according to the invention, the desired pH value of the aqueous compositions (C) or (S) is adjusted independently of one another using an acid or a base. Preferred acids for the compositions (C) according to the invention and used according to the invention are selected from the inorganic acids hydrochloric acid, sulfuric acid, and phosphoric acid, as well as the organic acids citric acid, lactic acid, gluconic acid, acetic acid, propionic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, galactaric acid (mucus acid), tartaric acid, malic acid, and mixtures of these acids. Hydrochloric acid is particularly preferred for adjusting the pH of the compositions (C).Preferred acids for the compositions (S) used according to the invention are selected from the inorganic acids sulfuric acid and phosphoric acid, as well as the organic acids citric acid, lactic acid, gluconic acid, acetic acid, propionic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, galactaric acid (mucus acid), tartaric acid, malic acid, and mixtures of these acids. Sulfuric acid, citric acid, lactic acid, and gluconic acid, as well as mixtures of these acids, are particularly preferred for adjusting the pH of the compositions (S).

[0067] Preferred bases are sodium hydroxide, potassium hydroxide, arginine, lysine, monoethanolamine, triethanolamine, 2-amino-2-methylpropan-1-ol, ammonia, and mixtures of these bases.

[0068] If the composition C according to the invention only realizes feature M1) according to which it has a pH value of 1.0 to 6.9, measured at 20°C, and no salt according to feature M2) is contained in C, the composition (S) is ammonia-free.

[0069] The compositions C and S used according to the invention contain the respective mandatory component, that is, the at least one plant polyphenol or the at least one silver salt, in a cosmetic carrier. In a first preferred embodiment according to the invention, the carrier is water.

[0070] Further dyeing processes preferred according to the invention are characterized in that the plant polyphenol-containing composition C contains water in an amount of 30.0–99.8 wt.%, preferably 50.0–98.0 wt.%, particularly preferably 70.0–90.0 wt.%, and extremely preferably 80.0–86.0 wt.%, based on the weight of composition C. Further dyeing processes preferred according to the invention are characterized in that the silver salt-containing composition S contains water in an amount of 30.0–99.8 wt.%, preferably 50.0–98.0 wt.%, particularly preferably 70.0–90.0 wt.%, and extremely preferably 80.0–86.0 wt.%, based on the weight of composition S.

[0071] To optimize the applicability of compositions C and S and their residence time on the keratin fibers, it is preferred that compositions C and S have a thickened consistency. Preferably, compositions C and S are available independently of each other, preferably as a gel, cream, or paste. Such carriers ensure homogeneous distribution and sufficient residence time of compositions C and S on the keratin fibers.

[0072] The compositions (C) and (S) used according to the invention, and preferably according to the invention, may optionally contain further additives to optimize their application properties. Preferred additives are, in particular, thickening agents that ensure that the compositions (C) and (S) adhere better to the hair during application.

[0073] According to the invention, particularly preferred compositions (C) and (S) each contain, independently of one another, at least one or more hydrophilic thickeners, which are preferably selected from polysaccharides that may be chemically and / or physically modified. Compounds from the group of polysaccharides are particularly preferred as hydrophilic thickeners according to the invention, since the basic structures of the polysaccharides are of natural origin and biodegradable.Preferred hydrophilic polysaccharide thickeners are selected from celluloses, cellulose ethers of C1-C4 alcohols, cellulose esters, xanthan gum, alginic acids (and their corresponding physiologically acceptable salts, the alginates), agar agar (with the polysaccharide agarose present as the main component in agar agar), starch fractions and starch derivatives such as amylose, amylopectin and dextrins, karaya gum, locust bean gum, gum arabic, pectins, dextrans and guar gum, and mixtures thereof.

[0074] Preferred cellulose ethers of C1-C4 alcohols and cellulose esters according to the invention are selected from methylcelluloses, ethylcelluloses, hydroxyalkylcelluloses (such as hydroxyethylcellulose), methylhydroxyalkylcelluloses and carboxymethylcelluloses (such as those with the INCI name Cellulose Gum) as well as their physiologically acceptable salts.

[0075] In preferred embodiments, xanthan gum is included as a hydrophilic thickener to ensure reliable viscosity control and residue-free application to keratin fibers and the scalp. In further preferred embodiments, carboxymethylcellulose (preferably sodium carboxymethylcellulose with the INCI name Cellulose Gum) is included as a hydrophilic thickener to ensure reliable viscosity control and residue-free application to keratin fibers and the scalp. In a preferred embodiment, carboxymethylcellulose may be the sole hydrophilic thickener. A combination of sodium carboxymethylcellulose and hydroxyethylcellulose is particularly preferred. The combination of sodium carboxymethylcellulose and xanthan gum may also be preferred according to the invention.

[0076] According to the invention, particularly preferred compositions (C) and (S) contain, each independently of the other, at least one hydrophilic thickener in a total amount of 0.1 to 5 wt.%, preferably 0.5 to 4 wt.%, more preferably 1 to 3.5 wt.% and most preferably 1.2 to 2 wt.%, each based on the weight of the respective composition (C) or composition (S).

[0077] According to the invention, particularly preferred compositions (C) and (S) each contain, independently of one another, at least one organic solvent having a phenyl group in the molecule. Preferably, this solvent is selected from phenoxyethanol, benzyl alcohol, and mixtures thereof. Surprisingly, it was found that such aromatic solvents can have a positive effect on the staining results of the dyeing process according to the invention; this was observed particularly when composition (C) contains such an aromatic solvent.

[0078] In a further preferred embodiment of the present invention, the compositions (C) preferred according to the invention contain, based on their weight, 0.1 to 3 wt.%, preferably 0.5 to 2.5 wt.%, more preferably 0.8 to 1.0 wt.%, at least one organic solvent having a phenyl group in the molecule. In a further preferred embodiment of the present invention, the compositions (C) according to the invention contain, based on their weight, 0.1 to 3 wt.%, preferably 0.5 to 2.5 wt.%, more preferably 0.8 to 1.0 wt.%, at least one organic solvent selected from phenoxyethanol, benzyl alcohol, and mixtures thereof.

[0079] Further compositions (C) and (S) particularly preferred according to the invention contain, each independently of the other, at least one aliphatic solvent selected from Ci-C4 alkanols and C2-Ci2 polyols, in particular selected from ethanol, isopropanol, n-propanol, ethylene glycol, 1,2-propanediol, glycerol, diethylene glycol, dipropylene glycol, 1,3-butylene glycol, 1,2-hexanediol, 1,6-hexanediol and 1,2-octanediol, as well as mixtures of these solvents.

[0080] Further compositions (C) and (S) particularly preferably used according to the invention each contain, independently of one another, at least one aliphatic solvent selected from Ci-C4 alkanols and C2-Ci2 polyols, in a total amount of 0.01–60 wt.%, preferably 0.1–30 wt.%, particularly preferably 0.5–20 wt.%, extremely preferably 1–10 wt.%, and more preferably 2–5 wt.%, in each case based on the weight of compositions (C) and (S), respectively. Other compositions (C) and (S) particularly preferably used according to the invention are characterized in that they each independently do not contain an aliphatic solvent selected from Ci-O4 alkanols and C2-Ci2 polyols.

[0081] According to the invention, particularly preferred compositions (C) and (S) contain, independently of each other, at least one oil. Preferred cosmetic oils are selected from natural and synthetic hydrocarbons, particularly preferably from paraffin oils, C8-O3o isoparaffins, especially isoeicosan, polyisobutenes and polydecenes, Cs-Cie isoparaffins, as well as 1,3-di-(2-ethylhexyl)cyclohexane; the benzoic acid esters of linear or branched Cs-22 alkanols; fatty alcohols with 6 to 30 carbon atoms, which are unsaturated or branched and saturated or branched and unsaturated; triglycerides of linear or branched, saturated or unsaturated, optionally hydroxylated Cs-22 fatty acids, especially natural oils; the dicarboxylic acid esters of linear or branched C22 alkanols;esters of linear or branched saturated or unsaturated fatty alcohols with 2–30 carbon atoms with linear or branched saturated or unsaturated fatty acids with 2–30 carbon atoms, which may be hydroxylated; the addition products of 1 to 5 propylene oxide units to mono- or polyhydric Cs-22 alkanols; the addition products of at least 6 ethylene oxide and / or propylene oxide units to mono- or polyhydric O3-22 alkanols; the O8-O22 fatty alcohol esters of mono- or polyhydric O2-O7 hydroxycarboxylic acids; the symmetrical, asymmetrical, or cyclic esters of carbonic acid with O3-22 alkanols, O3-22 alkanediols, or O3-22 alcantriols; esters of dimers of unsaturated Ci2-O22 fatty acids (dimer fatty acids) with monovalent linear, branched or cyclic O2-Ci8-alkanols or with polyvalent linear or branched O2-O6-alkanols; silicone oils and mixtures of the aforementioned substances.;

[0082] Further compositions (C) and (S) that are particularly preferred according to the invention each contain, independently of each other, at least one surfactant or one emulsifier.

[0083] Surfactants and emulsifiers according to the present application are amphiphilic (bifunctional) compounds consisting of at least one hydrophobic and at least one hydrophilic molecular moiety. The hydrophobic moiety is preferably a hydrocarbon chain with 8-28 carbon atoms, which may be saturated or unsaturated, linear or branched. A linear 08-028 alkyl chain is particularly preferred. Basic properties of the surfactants and emulsifiers are oriented absorption at interfaces, aggregation into micelles, and the formation of lyotropic phases. When selecting suitable surfactants according to the invention, it may be preferred to use a mixture of surfactants in order to optimally adjust the stability of the compositions (C) and (S) used according to the invention, independently of each other.Preferred surfactants and emulsifiers are selected from anionic, cationic, zwitterionic, amphoteric, and nonionic surfactants and emulsifiers, as well as mixtures of these substances. Further compositions (C) and (S) particularly preferred according to the invention each contain, independently of one another, at least one linear saturated alkanol with 12–30 carbon atoms.

[0084] Preferred linear saturated alkanols with 12 to 30 carbon atoms, particularly with 16 to 22 carbon atoms, are selected from cetyl alcohol, stearyl alcohol, arachidyl alcohol, behenyl alcohol, and lanolin alcohol, as well as mixtures of these alkanols. Particularly preferred alkanol mixtures according to the invention are those obtained during the industrial hydrogenation of vegetable and animal fatty acids. Preferably, the total amount of at least one linear saturated alkanol with 12 to 30 carbon atoms is 0.1 to 20 wt.%, more preferably 0.5 to 16.5 wt.%, and more preferably 3 to 10 wt.%, in each case based on the weight of composition (C) or (S).

[0085] Preferred kits and dyeing processes according to the invention are further characterized in that no hydrogen peroxide is used in them.

[0086] Regarding further preferred embodiments of the dyeing process according to the invention, what has been said about the kit components composition (C) and composition (S) according to the invention applies mutatis mutandis.

[0087] In order to preserve the hair-friendly potential of the natural dyes, the claimed method is preferably limited to such methods in which the keratinous fibers have not been treated with an oxidizing agent for a period of up to 7 days prior to the application of the compositions (C) and (S) used according to the invention.

[0088] Oxidizing agents commonly used in hair cosmetics, but which are not intended for hair treatment according to the invention, including as a pretreatment, include hydrogen peroxide, persulfates, perbromates, percarbonates, perborates, and percarbamides. Oxygen contained in ambient air does not constitute an oxidizing agent in the context of the invention.

[0089] In order to preserve the hair-protecting potential of the natural dyes, preferred methods according to the invention are limited to those methods in which the keratinous fibers have not been treated with a keratin-reducing compound for a period of up to 7 days before the application of the compositions (C) and (S) used according to the invention.

[0090] Preferably, the keratin fibers are washed and / or dried after rinsing out compositions (C) and (S). Washing can be done with a commercially available shampoo. Drying can be done without the active application of heat. However, drying can also be done with the application of heat at a temperature of 25–120 °C, particularly preferably at a temperature of 30–80 °C, and most preferably at a temperature of 35–60 °C. The application of heat is preferably done by a heat lamp, a drying rod, a drying hood, a flat iron, or a hairdryer.

[0091] The keratin fibers can be dried after each rinsing step with an absorbent cloth, such as a towel. Optionally, the towel-dried hair can also be partially or completely dried with a hairdryer or other heat source. Air drying is also possible.

[0092] Another feature of the dyeing process according to the invention is that the composition (C) is left to act on the keratin fibers for a period of 1 to 60 minutes, preferably 5 to 45 minutes, particularly preferably 20 to 35 minutes, and most preferably 25 to 30 minutes, after application.

[0093] After the exposure time for composition (C) has elapsed, the keratin fibers are rinsed with water to wash out composition (C).

[0094] Another feature of the dyeing process according to the invention is that the composition (S) is left to act on the keratin fibers for a period of 0.5 to 60 minutes, preferably 5 to 45 minutes, particularly preferably 20 to 35 minutes, and most preferably 25 to 30 minutes, after application.

[0095] After the application time for the composition (S) has elapsed, the keratin fibers are rinsed with water to wash out the composition (S). Optionally, washing with a commercially available shampoo can follow.

[0096] Further dyeing processes preferred according to the invention are characterized in that no oxidation dye precursors are used in them. Typical oxidation dye precursors are p-aminophenol, 4-amino-3-methylphenol, 4-amino-2-aminomethylphenol, 4-amino-2-(1,2-dihydroxyethyl)phenol, 4-amino-2-(diethylaminomethyl)phenol, 2-(2,5-diaminophenyl)ethanol, 2-(1,2-dihydroxyethyl)-p-phenylenediamine, N,N-bis-(2-hydroxyethyl)-p-phenylenediamine, N-(4-amino-3-methylphenyl)-N-[3-(1H-imidazol-1-yl)propyl]amine, N,N'-bis-(2-hydroxyethyl)-N,N'-bis-(4-aminophenyl)-1,3-diamino-propan-2-ol, Bis-(2-hydroxy-5-aminophenyl)methane, 1,3-bis-(2,5-diaminophen- oxy)propan-2-ol, N,N'-bis-(4-aminophenyl)-1,4-diazacycloheptane, 1,10-bis-(2,5-diaminophenyl)-1,4,7,10-tetraoxadecane, 2,4,5,6-tetraaminopyrimidine, 4-Hydroxy-2,5,6-triaminopyrimidine, 2-hydroxy-4,5,6-triaminopyrimidine, 2,3-diamino-6,7-dihydro-1H,5H-pyrazolo-[1,2-a]-pyrazol-1-one, 3-amino-phenol, 5-amino-2-methylphenol,3-Amino-2-chlor-6-methylphenol, 2-Hydroxy-4-aminophenoxy- ethanol, 5-Amino-4-chlor-2-methylphenol, 5-(2-Hydroxyethyl)-amino-2-methylphenol, 2,4-Dichlor-3- aminophenol, 2-Aminophenol, 3-Phenylendiamin, 2-(2,4-Diaminophenoxy)ethanol, 1 ,3-Bis(2,4-di- aminophenoxy)propan, 1-Methoxy-2-amino-4-(2-hydroxyethylamino)benzol, 1 ,3-Bis(2,4-diamino- phenyl)propan, 2, 6-Bis(2'-hydroxyethylamino)-1 -methylbenzol, 2-({3-[(2-Hydroxyethyl)amino]-4- methoxy-5-methylphenyl}amino)ethanol, 2-({3-[(2-Hydroxyethyl)amino]-2-methoxy-5-methylphenyl}- amino)ethanol, 2-({3-[(2-Hydroxyethyl)amino]-4,5-dimethylphenyl}amino)ethanol, 2-[3-Morpholin-4- ylphenyl)amino]ethanol, 3-Amino-4-(2-methoxyethoxy)-5-methylphenylamin, 1-Amino-3-bis-(2- hydroxyethyl)aminobenzol, Resorcin, 2-Methylresorcin, 4-Chlorresorcin, 1 ,2,4-Trihydroxybenzol, 2- Amino-3-hydroxypyridin, 3-Amino-2-methylamino-6-methoxypyridin, 2,6-Dihydroxy-3,4-dimethyl- pyridin, 3,5-Diamino-2,6-dimethoxypyridin, 1 -Phenyl-3-methylpyrazol-5-on, 1-Naphthol, 1 ,5-Dihydro- xynaphthalin, 2,7-Dihydroxynaphthalin, 1 ,7-Dihydroxynaphthalin, 1 ,8-Dihydroxynaphthalin, 4-Hydro- xyindol, 6-Hydroxyindol, 7-Hydroxyindol, 4-Hydroxyindolin, 6-Hydroxyindolin und 7-Hydroxyindolin.,

[0097] To make the compositions (C) according to the invention also olfactorily attractive to the user, further compositions (C) and (S) used particularly preferably according to the invention are characterized in that they each contain, independently of one another, at least one perfume oil which contains at least one fragrance compound or odorant compound. The definition of an odorant within the meaning of the present application corresponds to the skilled person's usual definition as found in the RÖMPP Chemistry Lexicon, as of December 2007. According to this definition, an odorant is a chemical compound with an odor and / or taste that excites the receptors of the hair cells of the olfactory system (adequate stimulus). The necessary physical and chemical properties for this are a low molar mass of a maximum of 300 g / mol, a high vapor pressure,Minimal water solubility, high lipid solubility, weak polarity, and the presence of at least one osmophoric group in the molecule are characteristic features. To distinguish volatile, low-molecular-weight substances, which are usually considered and used not as fragrances but primarily as solvents (and also not as such in the context of this application), such as ethanol, propanol, isopropanol, and acetone, from fragrances according to the invention, the fragrances according to the invention have a molar mass of 74 to 300 g / mol, contain at least one osmophoric group in the molecule, and possess an odor and / or taste, i.e., they stimulate the receptors of the hair cells of the olfactory system. Examples of ester-type fragrance and perfume compounds are benzyl acetate, phenoxyethyl isobutyrate, p-tert-butylcyclohexyl acetate, linalyl acetate, dimethylbenzylcarbinyl acetate (DMBCA), phenylethyl acetate, benzyl acetate, ethylmethylphenylglycinate, allylcyclohexyl propionate, and styralyl propionate.Benzyl salicylate, cyclohexyl salicylate, floramate, melusate, and jasmecyclate. Examples of ether-type fragrance and perfume compounds are benzyl ethyl ether and ambroxane; examples of aldehyde-type fragrance and perfume compounds are the linear alkanals with 8–18 carbon atoms, citral, citronellal, citronellyl oxyacetaldehyde, cyclamenaldehyde, lilial, and bourgeonal; examples of ketone-type fragrance and perfume compounds are the ionones, alpha-isomethyl ionone, and methylcedryl ketone; examples of alcohol-type fragrance and perfume compounds are anethole, citronellol, eugenol, geraniol, linalool, phenylethyl alcohol, and terpineol; examples of terpene-type fragrance and perfume compounds are limonene and pinene. Examples of fragrance and perfume compounds include pine, citrus, jasmine, patchouli, rose, ylang-ylang oil, clary sage oil, chamomile oil, clove oil, mint oil, cinnamon leaf oil, linden blossom oil, juniper berry oil, vetiver oil, and frankincense oil.Galbanum oil, labdanum oil, orange blossom oil, neroli oil, orange peel oil, and sandalwood oil, as well as essential oils such as angelica root oil, anise oil, arnica flower oil, basil oil, bay oil, bergamot oil, champaca flower oil, silver fir oil, silver fir cone oil, elemi oil, eucalyptus oil, fennel oil, spruce needle oil, geranium oil, ginger grass oil, guaiac wood oil, gurjun balsam oil, helichrysum oil, ho oil, ginger oil, iris oil, cajeput oil, calamus oil, chamomile oil, camphor oil, kanaga oil, cardamom oil, cassia oil, pine needle oil, kopa tva balsam oil, coriander oil, spearmint oil, caraway oil, cumin oil, lavender oil, lemongrass oil, lime oil, mandarin oil, lemon balm oil, musk seed oil, myrrh oil, clove oil, and niaouli oil. Orange oil, oregano oil, palmarosa oil, patchouli oil, Peruvian balsam oil, petitgrain oil, pepper oil, peppermint oil, pimento oil, pine oil, rose oil, rosemary oil, sandalwood oil, celery oil, spike oil, star anise oil, turpentine oil, thuja oil, thyme oil, verbena oil, juniper berry oil, wormwood oil, wintergreen oil, hyssop oil, cinnamon oil, citronella oilLemon oil and cypress oil. Other fragrance and scent compounds include ambrettolide, alpha-amylcinnamaldehyde, anethole, anisaldehyde, anisic alcohol, anisole, anthranilic acid methyl ester, acetophenone, benzylacetone, benzaldehyde, ethyl benzoate, benzophenone, benzyl alcohol, benzyl acetate, benzyl benzoate, benzyl formate, benzyl valerianate, borneol, bornyl acetate, α-bromostyrene, n-decylaldehyde, n-dodecylaldehyde, eugenol, eugenol methyl ether, eucalyptol, farnesol, fenchone, fenchyl acetate, geranyl acetate, geranyl formate, heliotropin, heptyne carboxylic acid methyl ester, heptaldehyde, hydroquinone dimethyl ether, hydroxycinnamaldehyde, hydroxycinnamaldehyde alcohol, indole, iron, isoeugenol, isoeugenol methyl ether, isosafrole, jasmon, and camphor. Karvakrol, Karvon, p-cresol methyl ether, coumarin, p-methoxyacetophenone, methyl n-amyl ketone, methyl anthranilic acid methyl ester, p-methyl acetophenone, methyl chavicol, p-methyl quinoline, methyl ß-naphthyl ketone, methyl n-nonylacetaldehyde, methyl n-nonyl ketone, muskone, ß-naphthol ethyl ether,β-Naphthol methyl ether, nerol, nitrobenzene, n-nonyl aldehyde, nonylic alcohol, n-octyl aldehyde, p-oxyacetophenone, pentadecanolide, β-phenylethyl alcohol, phenylacetaldehyde dimethyl acetal, phenylacetic acid, pulegone, safrole, isoamyl salicylate, methyl salicylate, hexyl salicylate, cyclohexyl salicylate, santalol, skatole, terpineol, thymene, thymol, γ-undecalactone, vanillin, veratraldehyde, cinnamaldehyde, cinnamyl alcohol, cinnamic acid, ethyl cinnamic acid, and benzyl cinnamic acid.

[0098] Other (more volatile) fragrance substances are alkyl isothiocyanates (alkyl mustard oils), butanedione, limonene, linalool, linalyl acetate and propionate, menthol, menthone, methyl-n-heptenone, phellandrene, phenylacetaldehyde, terpinyl acetate, citral and citrinellalal.

[0099] Preferably, mixtures of different fragrances are used, which together create an appealing scent.

[0100] Suitable perfume oils can also contain natural fragrance mixtures, such as those obtained from plant or animal sources, e.g., pine, citrus, jasmine, rose, lily, or ylang-ylang oil. Essential oils of lower volatility, which are usually used as aroma components, are also suitable as perfume oils, e.g., sage oil, chamomile oil, lemon balm oil, mint oil, cinnamon leaf oil, linden blossom oil, juniper berry oil, vetiver oil, olibanum oil, galbanum oil, laudanum oil, clove oil, iso-eugenol, thyme oil, bergamot oil, geranium oil, and rose oil.

[0101] According to the invention, compositions (C) and (S) that are particularly preferred are characterized in that they each contain, independently of one another, at least one fragrance in a total amount of 0.01 - 5 wt.%, preferably 0.1 - 3 wt.%, particularly preferably 0.5 - 2 wt.%, and most preferably 1 - 1.5 wt.%, respectively, based on the weight of composition (C) and (S), respectively.

[0102] The expression “each independently of each other” also includes the case where only one of the two compositions (C) and (S) used according to the invention contains the respective optional ingredient.

[0103] Another object of the present invention is a kit for the non-oxidative coloring of keratinous fibers, in particular human hair, comprising a composition C containing at least one polyphenol of plant origin, preferably at least one polyphenol from Reseda luteola, in a cosmetic carrier and further comprising at least one feature M selected from

[0104] M1) a pH value in the range of 1.0 to 6.9, measured at 20°C, and

[0105] M2) containing at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, and a composition S representing an aqueous solution of a silver salt, wherein, if only feature M1) is realized and not feature M2), at least one polyphenol of plant origin is not derived from Camellia sinensis and the silver salt-containing composition S is ammonia-free.

[0106] A further object of the present invention is a composition for the non-oxidative coloring of keratinous fibers, in particular human hair, containing at least one polyphenol of plant origin, preferably at least one polyphenol from Reseda luteola, in a cosmetic carrier and further comprising at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion. The above regarding preferred embodiments of the coloring process according to the invention applies mutatis mutandis to preferred embodiments of this composition according to the invention.

[0107] The above regarding preferred embodiments of the dyeing process according to the invention applies mutatis mutandis to preferred embodiments of the kit according to the invention and its components, composition C and composition S. A further object of the present invention is the use of at least one salt, selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, to improve the wash resistance of a non-oxidative dyeing of keratinous fibers by means of at least one polyphenol of plant origin and the aqueous solution of a silver salt.

[0108] What has been said about preferred embodiments of the dyeing process according to the invention applies mutatis mutandis to preferred embodiments of the use according to the invention for improving wash resistance.

[0109] Examples of implementation

[0110] The exemplary embodiments shown below are intended to explain the subject matter of the invention in more detail, without limiting it thereto.

[0111] The dyeing process according to the invention was carried out on strands of white buffalo belly hair (tied in a round, with approximately 8 cm of free hair).

[0112] In a first step, a 1% (w:w) aqueous suspension of Reseda luteola plant extract is prepared and subsequently acidified (HCl 10% w:w, H₂SO₄ 20% w:w to pH 3, measured at 20 °C). Alternatively, up to 5% (w:w) of the additives NaCl, Nal, or NH₄SCN is added. A strand of buffalo belly or human hair is then stirred in the suspension for 30 minutes (100–130 rpm). 714 mg of Reseda luteola extract is used for every 1000 mg of hair. The strand is then washed with deionized water for 60 seconds while combing and blow-dried for 90 seconds with a standard hairdryer, maintaining a distance of approximately 10–15 cm between the hairdryer and the strand. At this point, the strand appears unchanged in color.

[0113] In the second step, the treated strand is treated with a 0.1–1% (w:w) AgNOs solution (pH 4.5, measured at 20°C), preferably in the dark, for 10–30 minutes (stirring at 100–130 rpm). 71.4 mL of silver solution are used per 1000 mg of hair. The strand is then washed again for 60 seconds with deionized water while combing and blow-dried for 90 seconds with a standard hairdryer, maintaining a distance of approximately 10–15 cm between the hairdryer and the strand.

[0114] The strand, which remains unchanged in color, is now exposed to natural sunlight or a sunlight lamp (full-spectrum plant lamp, PAR38) with a UV component (similar to the solar spectrum), so that the color development begins.

[0115] A halide-dependent intensification of the color can be observed. The term "additive" refers below to the addition of halide salt or pseudohalide salt.

[0116] Figure 1 shows the pretreatment conditions of the hair strand and the influence of these additives in combination with and without the Reseda luteola plant extract. All strands were treated with a 1% w:w AgNO3 solution after treatment with Reseda (+additive) and developed under a sunlight lamp.

[0117] The starting point for the experiments was treatment with 10% HCl. Here, an intense color was achieved in the first step by combining it with Reseda luteola. The color impression, albeit weaker, that could also be achieved without the addition of Reseda luteola in this case laid the foundation for a more in-depth investigation of the influence of the additives. Replacing the HCl with 5% NaCl already showed a strong red coloration without the addition of Reseda, which could be further intensified in combination with 1% Reseda. To differentiate the influence of the acidic environment from that of the chloride, a chloride-free acid (H₂SO₄, 20%) was used to adjust the pH. Without the addition of Reseda luteola, no color development was observed. This led to the conclusion that an acidic pH value alone cannot be decisive for color development. The combination of H₂SO₄ with 1% Reseda luteola, however, showed a red coloration.

[0118] To further limit the influence of chloride on the color result, it was replaced with the halide nal (sodium iodide) and a pseudo-halide, NH4SCN. This step allowed the color palette to be expanded to include darker, brownish tones as well as lighter, caramel shades, as shown in Figure 2. Figure 2 clearly shows that the use of NH4SCN instead of NaCl in combination with 1 wt% Reseda luteola produces a dark brown tone. The resulting shade without the addition of Reseda luteola is significantly lighter.

[0119] The exchange of chloride for iodide shows lighter, reddish-brown hues, the expression of which is very weak without the combination with Reseda luteola.

[0120] The control tests confirm the significant influence of the additive on the coloring. The most intense color result in both cases is achieved by combining Reseda luteola, the additive, and silver. Strands pre-treated with Reseda but without the additive appear paler.

[0121] Furthermore, it can be observed for all investigated additives that subsequent washing of the fully developed strand results in a further intensification of the color, see Figure 3. The strands treated with NH4SCN as an additive become more radiant after the washing process. A particularly noticeable difference is visible in the strands treated with Nal as an additive. The washing process causes a significant intensification of the color. Microtome sections of the strands after 4 wash cycles of 6 washes each show an intensification of the color on the hair and a deeper diffusion of the particles into the interior of the hair, see Figure 5.

[0122] The coloration is based on the in-situ formation of silver nanoparticles. Through the combination of Ag(l) with reducing polyphenols, reduction to Ag(0) occurs under the influence of electromagnetic radiation. This Ag(0) then agglomerates into nanoparticles, with both the polyphenols and the halide playing a crucial role in stabilizing the particles. The particles exhibit high mobility and are able to diffuse into the hair cortex, as shown in Figure 4. To illustrate the uniform red coloration, a light microscope image of cross-sections of a single hair treated with 1 wt% Reseda luteola, 5 wt% NaCl, and 1 wt% Ag is shown in Figure 4. A penetration depth of the coloring components between 15 and 20 pm is evident, with peak values ​​up to 30 pm. The formed particles are able to penetrate deep into the hair.

[0123] Tests on wash fastness show that even 24 washes have no visible effect on the color intensity. For these tests, strands of hair were treated with a 1 wt% aqueous suspension of Reseda luteola plant extract, adjusted to pH 3 with HCl, and subsequently with a 1 wt% aqueous solution of AgNO3. After 6 washes, an intensification of color brilliance was observed, as a grayish cast washed off the hair. This observation was confirmed by an increase in the L*, a*, and b* values. After 12 and 18 washes, respectively, no further change in color intensity was observed, evidenced by only minimal changes in the L*, a*, and b* values. After 18 washes, the L* value (brightness) remained unchanged, suggesting that no significant amount of color was washed off.The changes in the a* and b* values ​​after 18 washes are minimal and imperceptible to the human eye. Both the visual impression and the calculated L*, a*, b*, and AE values ​​suggest that no significant amounts of color were removed from the hair during the wash fastness tests, but rather that the strands benefited from the washing process, as an intensification of color brilliance was observed after 6 washes.

[0124] The high wash fastness is further demonstrated by cross-sections of the hair. With an increasing number of washes, a greater penetration depth of the red dye into the hair shaft was observed. Strands were used that had been treated with 1% Reseda at pH 3 (adjusted with HCl) followed by 1% AgNO3. The average penetration depth of the dye at the beginning of the study was 9.3 ± 1.7 pm. The relative penetration depth, which takes individual hair diameter into account, was therefore 10–14%. A ring-shaped penetration pattern was observed, reminiscent of demi-permanent hair dyes, which confirms the high wash resistance. After six washes, an increase in penetration depth (13.7 ± 3.0 pm, 14–17%) was observed. The initial contact of the hair fiber with water and a surfactant after the dyeing process induces the mobilization of the dye deeper into the hair. Further increases in penetration depths were also observed after 12 (18.9±4.The highest penetration depth of 20.8 ± 3.2 pm (27%) was observed after 18 washes. At this point, the color appeared as several concentric color rings within the hair. After 24 washes, the average penetration depth decreased to 14.6 ± 6.7 pm (18–23%). Several concentric color rings were also observed at this stage.

[0125] The results show a continuous diffusion of the red dye particles into the hair shaft under the influence of water for up to 18 washes. Subsequently, a migration of the particles to the outer layers was observed. The fundamental movement of the particles—whether inwards or outwards—suggests that there are no strong covalent interactions between the dye molecules and components of the hair. Simultaneously, repeated exposure to water did not significantly remove the dye from the hair, suggesting a certain affinity between the dye and the hair fiber. Considering the critical molecular diameter for molecules to penetrate the hair cuticle, the species must be smaller than 6–8 Å (0.6–0.8 nm) to move within the hair.The resulting characteristic penetration pattern can presumably be attributed to various hair-intrinsic structures that are made visible by aggregated silver particles.

Claims

Patent claims 1. A process for the non-oxidative coloring of keratinous fibers, in particular human hair, comprising the following process steps in the specified order: i. Providing a composition C containing at least one polyphenol of plant origin, preferably at least one polyphenol from Reseda luteola, in a cosmetic carrier; ii. Applying the composition C to the keratin fibers to be colored; iii. Allowing the composition C to act for a period of 1 to 60 minutes; iv. Rinsing off the composition C; v. Optionally drying the keratin fibers; vi. Subsequently treating the keratin fibers with a composition S, which is an aqueous solution of a silver salt, for a period of 0.5 to 60 minutes; vii. Rinsing off the silver salt-containing composition S; and viii.optional washing and / or drying of the keratin fibers, wherein no oxidizing agents other than atmospheric oxygen are used in the process, characterized in that the composition C has at least one feature M selected from M1) a pH value in the range of 1.0 to 6.9, measured at 20°C, and M2) containing at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, wherein, if only feature M1) is realized and not feature M2), at least one polyphenol of plant origin is not derived from Camellia sinensis and the silver salt-containing composition S is ammonia-free.

2. A method for the non-oxidative coloring of keratin fibers, in particular human hair, according to claim 1, characterized in that the keratin fibers are exposed to electromagnetic radiation following process step vii. or viii.

3. Method according to claim 2, characterized in that the electromagnetic radiation to which the keratin fibers are exposed following process step vii. or viii. electromagnetic radiation is selected from a natural light source, preferably selected from daylight from the sun.

4. Method according to one of claims 2 or 3, characterized in that the keratin fibers are exposed to electromagnetic radiation for a period of 0.5 to 60 minutes, preferably 1 to 45 minutes, Preferably, the exposure should be for 5-30 minutes, and most preferably for 10-15 minutes.

5. A method for the non-oxidative dyeing of keratinous fibers, in particular human hair, according to one of claims 1-4, characterized in that the composition C, which contains at least one plant polyphenol, additionally contains one or more salts selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, and has a pH value of 1.0 to 11.0, more preferably 2.5 to 9.0, particularly preferably 3.0 to 8.0, more preferably 3.0 to > 6.9, more preferably 3.5 to 6.9, more preferably 4.0 to 5.5, in each case measured at 20°C.

6. A method for the non-oxidative dyeing of keratinous fibers, in particular human hair, according to any one of claims 1 to 5, characterized in that the composition C, which contains at least one plant polyphenol, additionally contains one or more salts selected from sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, ammonium fluoride, ammonium chloride, ammonium bromide, ammonium iodide, lithium fluoride, lithium chloride, lithium bromide, lithium iodide, rubidium fluoride, rubidium chloride, rubidium bromide, rubidium iodide, ammonium thiocyanate, sodium thiocyanate and potassium thiocyanate, as well as mixtures of the aforementioned salts, preferably in a total amount of 0.1 to 10.0 wt.%, more preferably 0.5 to 7.0 wt.%, particularly preferably 1.0 to 6.0 wt.%, and extraordinarily preferably 2.5 to 5.0 wt.%. 3.0 to 4.0 wt.%, based on the weight of composition C.

7. Method according to one of claims 1 - 6, characterized in that the at least one plant polyphenol, preferably derived from Reseda Luteola, is contained in a total amount of 0.1 - 50 wt.%, preferably 0.5 - 20 wt.%, particularly preferably 0.8 - 10 wt.%, and most preferably 1 - 2 wt.%, based on the weight of composition C.

8. Method according to any one of claims 1 - 7, characterized in that the composition C contains water in an amount of 30.0 - 99.8 wt.%, preferably 50.0 - 98.0 wt.%, particularly preferably 70.0 - 90.0 wt.%, extraordinarily preferably 80.0 - 86.0 wt.%, based on the weight of the composition C.

9. Method according to any one of claims 1-8, characterized in that the at least one silver salt is selected from silver nitrate, silver sulfate, silver citrate, silver dihydrogen citrate, silver- lactate, silver acetate, silver malate, silver succinate, silver tartrate, silver almondate, silver salicylate, silver gluconate, silver adipate and silver galactarate, as well as mixtures of these salts, wherein silver nitrate, silver sulfate, silver citrate, silver dihydrogen citrate and silver lactate, as well as mixtures of these salts, are particularly preferred.

10. Method according to any one of claims 1-9, characterized in that the at least one silver salt is contained in a total amount of 0.05-2 wt.%, preferably 0.1-1.5 wt.%, particularly preferably 0.2-0.8 wt.%, and most preferably 0.3-0.5 wt.%, in each case based on the weight of the composition S.

1. Method according to one of claims 1-10, characterized in that the composition S has a pH value of 2.0 to 8.0, preferably 3.0 to 7.5, particularly preferably 4.0 to 7.0, and most preferably 4.5 to 6.5, each measured at 20°C.

12. A non-oxidative dyeing agent for keratinous fibers, especially human hair, containing at least one polyphenol of plant origin, preferably at least one polyphenol from Reseda luteola, in a cosmetic carrier and further comprising at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion.

13. Kit for the non-oxidative coloring of keratinous fibers, in particular human hair, comprising a composition C containing at least one polyphenol of plant origin, preferably at least one polyphenol from Reseda luteola, in a cosmetic carrier and further comprising at least one feature M selected from M1) a pH value in the range of 1.0 to 6.9, measured at 20°C, and M2) containing at least one salt selected from the alkali metal salts or the ammonium salts of a halide anion or a pseudohalide anion, and a composition S representing an aqueous solution of a silver salt, wherein, if only feature M1) is realized and not feature M2), at least one polyphenol of plant origin is not derived from Camellia sinensis and the silver salt-containing composition S is ammonia-free.

14. Kit for non-oxidative staining according to claim 13, characterized in that the composition (C) is an agent according to any one of claims 5 - 8.

15. Kit for non-oxidative staining according to claim 13 or 14, characterized in that the composition (S) is an agent according to one of claims 9 - 11.

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