Hair dyeing with coreopsis polyphenol and fe(II) mordant

Abstract

The invention relates to a method and to a kit for dyeing keratin-containing fibers, in particular human hair, using selected Coreopsis polyphenols as natural dyes and an iron(II) salt of an organic carboxylic acid.

Description

[0001] Henkel AG & Co. KGaA

[0002] December 11, 2025

[0003] “Hair coloring with Coreops / s polyphenol and Fe(ell) mordant”

[0004] The invention relates to a method and a kit for dyeing keratin-containing fibers, in particular human hair, using selected Coreops / s polyphenols as natural dyes and an iron(II) salt of an organic carboxylic acid.

[0005] 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 and alkalizing agents, which can damage the hair structure. Certain cationic direct dyes are also capable of achieving hair color changes with excellent colorfastness. These dyes contain synthetic dyes.

[0006] A growing number of consumers desire hair dyes and hair coloring processes based on natural dyes, even if these products and processes are inferior to the aforementioned products and processes in terms of authenticity, coverage, and color variety.

[0007] Besides dyeing with henna, which is obtained from the plant Lawsonia inermis, the coloring of hair with certain polyphenols, especially tannins and pseudotannins, has also been known for a long time. Such polyphenols are extracted from specific parts of plants. However, it is also possible to use powdered plant parts with a high polyphenol content in the dye. In addition, it is possible to use pure polyphenols according to the invention. The desired polyphenols can also 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...Polyphenols of plant origin are known in the prior art, for example from US20230313246A1 or JP2022038951A. Petrochemically synthesized Coreops / s polyphenols are also included within the scope of the present invention. The Coreops / s polyphenols used according to the invention can be produced synthetically or biotechnologically, or obtained from natural sources. The Coreops / s polyphenols used according to the invention can be extracted, for example, from plants, animals, fungi, algae, or bacteria. The Coreops / s polyphenols used according to the invention can also be obtained from genetically modified fungi, algae, or bacteria.

[0008] The adhesion of the polyphenol dye to the hair or keratin fibers, and thus the colorfastness, the resulting shade, and the color intensity, can be positively influenced by certain divalent, trivalent, or higher-grade metal salts. This metal salt-assisted color intensification is also known as mordanting. The principle is known in the art.

[0009] State of the art

[0010] German patent application EP327345A2 discloses a composition for darkening hair, comprising a first component formulated as a shampoo and containing at least one iron(II) salt (i.e., a mordant), and a second component containing at least one organic compound, e.g., propyl gallate, as a colorant. After application of the second component, the hair is darkened as a result of the formation of a dark-colored complex of iron(II) and propyl gallate. German patent application W02010094207A1 discloses a method for coloring hair in which the hair is first treated with a keratin reducing agent, thereby breaking down the hair structure. A composition containing an iron(II) salt as a mordant and an antioxidant, and subsequently a hair coloring composition containing an emollient and a polyphenol colorant, are applied to the hair.The dyeing of wool with Coreopsis tinctoria extracts and various metal salts is known from patent RO 104341 B1.

[0011] Task

[0012] The present invention was based on the objective of providing a method for dyeing keratin-containing fibers, in particular human hair, which causes the least possible damage to the keratin structure.

[0013] The present invention was further based on the objective of providing a method for dyeing keratin-containing fibers, in particular human hair, using natural dyes, which achieves a dyeing with high color intensity.

[0014] Another task was to provide a method for dyeing keratin-containing fibers, especially human hair, using natural dyes, which achieves a dyeing with as little yellow tint as possible.

[0015] Another task was to provide a method for dyeing keratin-containing fibers, especially human hair, using natural dyes, which achieves particularly chromatic colorations.

[0016] Furthermore, the resulting dyes should have the highest possible fastness properties, especially high wash fastness.

[0017] Surprisingly, it was found that the dyeing process described in the patent claims achieves intense colors with minimal yellowing. Furthermore, the dyeing process according to the invention resulted in colors with improved wash fastness. The present invention relates to a process for the non-oxidative dyeing of keratin fibers, in particular human hair, with natural dyes, comprising the following process steps in the specified order:

[0018] a) Applying an aqueous composition (T) having a pH value in the range of 3.5 to 7.8, preferably in the range of 4.5 to 7.5, particularly preferably in the range of 4.7 to 5.7, each measured at 20°C, to the keratin fibers, wherein the composition (T) comprises the following:

[0019] i. one or more polyphenols that occur naturally in plants of the genus Coreopsis, preferably in plants of the species Coreopsis tinctoria, and that are available via the shikimate biosynthesis pathway and

[0020] - have at least 2 hydroxy groups in the molecule and

[0021] - have a molar mass in the range of 170 to 20,000 g / mol,

[0022] - wherein at least one compound selected from marein and okanin is included as the coreops / s polyphenol;

[0023] ii. optionally a buffer system, selected from a mixture of a moderately strong or weak acid with its conjugate or corresponding base (or the respective salt) and a mixture of a moderately strong or weak base with its conjugate or corresponding acid,

[0024] b) Allow to act for a period of 30 seconds to 60 minutes, preferably 5 to 45 minutes, particularly preferably 15 to 30 minutes,

[0025] c) Rinsing the keratin fibers with water,

[0026] d) optional drying of the keratin fibers,

[0027] e) immediately afterwards applying an aqueous composition (M) having a pH value in the range of 2.5 to 7.5, preferably in the range of 5.2 to 6.0, particularly preferably in the range of 5.4 to 5.8, in each case measured at 20°C, to the keratin fibers, wherein the composition (M) comprises the following:

[0028] iii. at least one salt of the divalent iron cation Fe(ll) of an organic carboxylic acid in a total amount of 0.001 - 3.0 wt.%, preferably 0.01 - 2 wt.%, particularly preferably 0.1 - 1 wt.%, extremely preferably 0.1 - 0.5 wt.%, in each case based on the weight of the composition (M),

[0029] iv. optionally a buffer system, selected from a mixture of a moderately strong or weak acid with its conjugate or corresponding base (or the respective salt) and a mixture of a moderately strong or weak base with its conjugate or corresponding acid,

[0030] f) Allow to act for a period of 30 seconds to 60 minutes, preferably 5 to 45 minutes, particularly preferably 15 to 30 minutes,

[0031] g) Rinsing the keratin fibers with water,

[0032] h) optional drying of the keratin fibers, whereby no oxidizing agent other than atmospheric oxygen, nor elemental iron, sponge iron, copper salts and aluminum salts are used in the process.

[0033] In order to preserve the hair-friendly potential of natural dyes, the claimed process is limited to those processes in which no oxidizing agent other than atmospheric oxygen is used.

[0034] Oxidizing agents commonly used in hair cosmetics, but which are not intended for hair treatment according to the invention, include hydrogen peroxide, persulfates, perbromates, percarbonates, perborates, and percarbamides. Atmospheric oxygen is not considered an oxidizing agent in the context of the invention.

[0035] In the first process step, an aqueous composition (T) is applied to the hair to be dyed, which is preferably dry. The aqueous composition (T) has a pH value in the range of 3.5 to 7.8, preferably in the range of 4.5 to 7.5, and particularly preferably in the range of 4.7 to 5.7, in each case measured at 20°C. The aqueous composition (T) contains, as a natural dye, one or more polyphenols that occur naturally in plants of the genus Coreopsis, preferably in plants of the species Coreopsis tinctoria, and which—according to Quideau's definition of polyphenols—are obtainable via the shikimate biosynthesis pathway and furthermore have at least two hydroxyl groups in the molecule and whose molar masses are in the range of 170 to 20,000 g / mol, preferably 290 to 3,000 g / mol, wherein the Coreops / s polyphenol is at least one compound selected from marein and okanin.

[0036] Okanin is 2',3,3',4,4'-pentahydroxychalcone. Marein is a glucoside of okanin, more precisely, okanin-4'-O-glucoside.

[0037] Polyphenols that occur naturally in Coreopsis

[0038] According to the invention, coreops / s-polyphenols are understood to be polyphenols that are obtainable via the shikimate biosynthesis pathway and

[0039] - have at least 2 hydroxy groups in the molecule and

[0040] - have a molar mass in the range of 170 to 20,000 g / mol and

[0041] - which occur naturally in Coreopsis.

[0042] Preferred staining processes according to the invention are characterized in that, in addition to the at least one Coreops / s polyphenol selected from marein and okanin, at least one further Coreops / s polyphenol selected from flavanomarein, isokanin, maritimetin, maritimein, coreopsin, quercetagetin-7-O-glycoside, chlorogenic acid, butein, butin, luteolin, eriodictyol, quercetin, sulfuretin, taxifolin, taxifolin-7-O-glucoside, 3,5-dicaffeoylquinic acid, isocoreopsin, isoliquiritigenin, and apigenin, as well as mixtures thereof, are included. The Coreops / s polyphenols used according to the invention need not necessarily be obtained from a plant of the genus Coreopsis, for example, by extraction.They can equally well be obtained by a biotechnological manufacturing 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 polyphenols of plant origin are known in the prior art, for example, from US20230313246A1 or JP2022038951A. Petrochemically synthesized Coreops / s polyphenols are also included within the scope of the present invention. The Coreops / s polyphenols used according to the invention can be produced synthetically or biotechnologically, or obtained from natural sources. The Coreops / s polyphenols used according to the invention can, for example, be extracted from plants, animals, fungi, algae, or bacteria.The Coreops / s polyphenols used according to the invention can also be obtained from genetically modified fungi, algae or bacteria.

[0043] According to the invention, preferred polyphenols have 3 to 12, preferably 4 to 8, particularly preferably 4 to 5 hydroxy groups and two to three phenyl groups.

[0044] Further dyeing processes preferred according to the invention are characterized in that the at least one Coreops / s polyphenol is contained in the form of at least one ground plant part of the plant genus Coreopsis. Plant parts preferred according to the invention, which can preferably be used in ground form, are flowers, buds, leaves, stems, seeds, fruits, galls, pods, husks, fruit peels, seed coats, rhizome (rootstock), roots, bark, stem wood, and heartwood. Plant parts preferred according to the invention, which can preferably be used in ground form, are flowers or buds, in particular flowers or buds of the genus Coreopsis, especially flowers or buds of Coreopsis tinctoria.

[0045] Further dyeing processes preferred according to the invention are characterized in that the at least one Coreops / s polyphenol is contained in the form of at least one plant part extract of the plant genus Coreopsis. Plant parts preferred according to the invention, from which extracts preferred according to the invention can be obtained, are flowers, buds, leaves, stems, seeds, fruits, galls, pods, husks, fruit shells, seed coats, rhizomes, roots, bark, stem wood, and heartwood. Extracts from flowers or buds, in particular flowers or buds of the genus Coreopsis, especially flowers or buds of Coreopsis tinctoria, are preferably used according to the invention.Suitable extraction agents are C1-C4 alkanols and esters with Ci-C4 carboxylic acids thereof and C2-C4 polyols, in particular ethanol, isopropanol, n-propanol, n-butanol, ethyl acetate, ethylene glycol, 1,2-propanediol, glycerol and 1,3-butylene glycol, furthermore water, in particular hot water with a temperature of 45-100 °C, 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. Preferred extraction agents according to the invention are anhydrous ethanol (absolute ethanol), 96 vol% ethanol (balance water and optionally denaturant), 80 vol% ethanol (balance water and optionally denaturant), and 55 vol% ethanol (balance water and optionally denaturant).

[0046] Further dyeing processes preferred according to the invention are characterized in that the at least one Coreops / s polyphenol is derived from a plant selected from the Coreops / s sections Calliopsis, Coreopsis, Electra, Eublepharis, Gyrophyllum, Leptosyne, Pseudo-agarista, Pugiopappus, Tuckermannia, Anathysana, Silphidium and the species Coreopsis capillacea and Coreopsis fasciculata.

[0047] Further dyeing processes preferred according to the invention are characterized in that the at least one Coreops / s polyphenol is derived from a plant selected from Coreopsis tinctoria, Coreopsis basalis, Coreopsis auriculata, Coreopsis grandiflora, Coreopsis intermedia, Coreopsis lanceolata, Coreopsis pubescens, Coreopsis mutica, Coreopsis gladiata, Coreopsis integrifolia, Coreopsis nudata, Coreopsis rosea, Coreopsis major, Coreopsis palmata, Coreopsis pulchra, Coreopsis tripteris, Coreopsis verticillata, Coreopsis californica, Coreopsis latifolia, Coreopsis capillacea and Coreopsis fasciculata.

[0048] Further staining processes preferred according to the invention are characterized in that the at least one coreops / s polyphenol was produced by a biotechnological process. Further staining processes preferred according to the invention are characterized in that the at least one coreops / s polyphenol was obtained from plants, animals, fungi, algae, or bacteria, optionally genetically modified.

[0049] Further dyeing processes preferred according to the invention are characterized in that the aqueous composition (T), based on its weight, contains at least one polyphenol, including at least one compound selected from marein and okanin, in a total amount of 0.001 - 5 wt.%, preferably 0.005 - 1 wt.%, particularly preferably 0.01 - 0.5 wt.%, and most preferably 0.01 - 0.1 wt.%.

[0050] The pH value of the aqueous composition (T) used according to the invention is in the range of 3.5 to 7.8, preferably in the range of 4.5 to 7.5, and particularly preferably in the range of 4.7 to 5.7, in each case measured at 20°C. It may be preferred according to the invention that this corresponds to the pH value of the composition (T) that is established when the at least one Coreopsis polyphenol or the Coreopsis / s polyphenol-containing extract or plant part is dissolved or suspended in water without the presence of any further pH regulators.

[0051] In another preferred embodiment of the invention, the pH of the composition (T) is adjusted using a buffer system selected from a mixture of a moderately strong or weak acid with its conjugate or corresponding base (or the respective salt) and a mixture of a moderately strong or weak base with its conjugate or corresponding acid. In a third preferred embodiment of the invention, the pH of the composition (T) is adjusted using an acid and / or a base.

[0052] According to the invention, preferably used aqueous compositions (T) are characterized in that they contain a buffer system selected from a mixture of a medium-strength or weak acid with its conjugated or corresponding base (or the respective salt) and a mixture of a medium-strength or weak base with its conjugated or corresponding acid.

[0053] According to the invention, preferably suitable corresponding acid-base pairs are those that stabilize the aqueous composition (T) used according to the invention in the pH range of 3.5 to 7.8, preferably in the range of 4.5 to 7.5, and particularly preferably in the range of 4.7 to 5.7, in each case measured at 20°C. According to the invention, particularly preferred buffer systems are selected from

[0054] - Mixtures of citric acid and its salts, in particular the alkali metal citrates, in particular the sodium salts, in particular trisodium citrate,

[0055] - Mixtures of tartaric acid and its salts, in particular the alkali metal tartrates, in particular the potassium salts, in particular potassium hydrogen tartrate,

[0056] - Mixtures of phthalic acid and its salts, in particular the potassium salts, especially potassium hydrogen phthalate,

[0057] - Mixtures of lactic acid and its salts, especially lactic acid / sodium lactate mixtures,

[0058] - Mixtures of gluconic acid and its salts, especially gluconic acid / sodium gluconate mixtures,

[0059] - Mixtures of succinic acid and its salts, in particular the sodium salts, especially sodium hydrogen succinate and disodium succinate, as well as

[0060] - Mixtures of malic acid and its salts, especially the sodium salts, in particular sodium hydrogen malate and disodium malate.

[0061] A buffer system that is particularly preferred according to the invention is formed from citric acid and at least one sodium salt of citric acid; mixtures of citric acid and trisodium citrate are extremely preferred.

[0062] Other buffer systems, e.g., acetic acid / sodium acetate, are also suitable in principle according to the invention. However, due to the vinegar odor, such a buffer is not acceptable for the production of a cosmetic market product.

[0063] Preferred dyeing processes according to the invention are characterized in that the aqueous composition (T), based on its weight, contains a buffer system in an amount of 0.5 - 5 wt.%, preferably 0.8 - 4.5 wt.%, particularly preferably 1.5 - 3.5 wt.%, and most preferably 2.1 - 3.0 wt.%.

[0064] Preferred dyeing processes according to the invention are characterized in that the aqueous composition (T), based on its weight, contains as a buffer system 0.2 - 1.5 wt.%, preferably 0.3 - 1.4 wt.%, particularly preferably 0.5 - 1.1 wt.%, extremely preferably 0.6 - 0.9 wt.% citric acid and 0.3 - 3.5 wt.%, preferably 0.5 - 3.1 wt.%, particularly preferably 1.0 - 2.4 wt.%, extremely preferably 1.5 - 2.1 wt.% trisodium citrate.

[0065] Preferred dyeing processes according to the invention are characterized in that the aqueous composition (T), based on its weight, contains as a buffer system 0.2 - 1.5 wt.%, preferably 0.3 - 1.4 wt.%, particularly preferably 0.5 - 1.1 wt.%, extremely preferably 0.6 - 0.9 wt.% gluconic acid and 0.3 - 3.5 wt.%, preferably 0.5 - 3.1 wt.%, particularly preferably 1.0 - 2.4 wt.%, extremely preferably 1.5 - 2.1 wt.% sodium gluconate.

[0066] Preferred dyeing processes according to the invention are characterized in that the aqueous composition (T), based on its weight, contains as a buffer system 0.2 - 1.5 wt.%, preferably 0.3 - 1.4 wt.%, particularly preferably 0.5 - 1.1 wt.%, extremely preferably 0.6 - 0.9 wt.% lactic acid and 0.3 - 3.5 wt.%, preferably 0.5 - 3.1 wt.%, particularly preferably 1.0 - 2.4 wt.%, extremely preferably 1.5 - 2.1 wt.% sodium lactate.

[0067] Preferred dyeing processes according to the invention are characterized in that the aqueous composition (T), based on its weight, contains as a buffer system 0.2 - 1.5 wt.%, preferably 0.3 - 1.4 wt.%, particularly preferably 0.5 - 1.1 wt.%, extremely preferably 0.6 - 0.9 wt.% succinic acid and 0.3 - 3.5 wt.%, preferably 0.5 - 3.1 wt.%, particularly preferably 1.0 - 2.4 wt.%, extremely preferably 1.5 - 2.1 wt.% disodium succinate. Preferred dyeing processes according to the invention are characterized in that the aqueous composition (T), based on its weight, contains as a buffer system 0.2 - 1.5 wt.%, preferably 0.3 - 1.4 wt.%, particularly preferably 0.5 - 1.1 wt.%, extremely preferably 0.6 - 0.9 wt.% succinic acid and 0.3 - 3.5 wt.%, preferably 0.5 - 3.1 wt.%, particularly preferably 1.0 - 2.4 wt.%, extremely preferably 1.5 - 2.1 wt.% sodium hydrogen succinate.

[0068] Preferred staining processes according to the invention are characterized in that the aqueous composition (T), based on its weight, contains as a buffer system 0.2–1.5 wt.%, preferably 0.3–1.4 wt.%, particularly preferably 0.5–1.1 wt.%, extremely preferably 0.6–0.9 wt.% malic acid and 0.3–3.5 wt.%, preferably 0.5–3.1 wt.%, particularly preferably 1.0–2.4 wt.%, extremely preferably 1.5–2.1 wt.% disodium malate. Preferred staining processes according to the invention are characterized in that the aqueous composition (T), based on its weight, contains as a buffer system 0.2–1.5 wt.%, preferably 0.3–1.4 wt.%, particularly preferably 0.5–1.1 wt.%, extremely preferably 0.6–0.9 wt.% malic acid and 0.3–3.5 wt.% preferably contains 0.5 - 3.1 wt.%, particularly preferably 1.0 - 2.4 wt.%, extremely preferably 1.5 - 2.1 wt.% sodium hydrogen malate.

[0069] In further compositions (T) preferably used according to the invention, the water content is 40 - 99.5 wt.%, preferably 50 - 98 wt.%, particularly preferably 60 - 97 wt.%, and most preferably 70 - 95 wt.%, in each case based on the weight of the composition (T).

[0070] Another feature of the dyeing process according to the invention is that the composition (T) is left to act on the keratin fibers for a period of 30 seconds to 60 minutes, preferably 5 to 45 minutes, particularly preferably 15 to 30 minutes, after application.

[0071] Normally, the application and the exposure time of the composition (T) take place at a temperature in the range of 17 to 25 °C, which is referred to as "room temperature".

[0072] Surprisingly, it was found that a more intense coloration can be achieved if the composition (T) is allowed to act, and possibly also the composition (T) is applied to the keratin fibers, at a temperature in the range of 26 to 40 °C, preferably at a temperature in the range of 30 to 37 °C.

[0073] A particularly preferred dyeing process according to the invention is therefore characterized in that the reaction of the composition (T) takes place at a temperature in the range of 26 to 40 °C, preferably at a temperature in the range of 30 to 37 °C.

[0074] Another dyeing method preferred according to the invention is characterized in that the application of the composition (T) to the keratin fibers takes place at a temperature in the range of 26 to 40 °C, preferably at a temperature in the range of 30 to 37 °C.

[0075] After the exposure time for the composition (T) has elapsed, the keratin fibers are rinsed with water to wash out the composition (T).

[0076] Optionally, the keratin fibers can be dried after this rinsing step. Drying can be done with an absorbent cloth, for example, a towel. The towel-dried hair can optionally also be partially or completely dried with a hairdryer or other heat source. Allowing the keratin fibers to air dry is also possible. Another feature of the dyeing process according to the invention is that, immediately following the rinsing of the composition (T) and optionally immediately following the drying step, an aqueous composition (M) is applied to the keratin fibers, which has a pH value in the range of 2.5 to 7.5, preferably in the range of 5.2 to 6.0, and particularly preferably in the range of 5.4 to 5.8, in each case at 20°C (process step e)).

[0077] The term "immediately thereafter" primarily means that no further composition is applied to the keratin fibers between the mandatory process steps c) and e). Furthermore, "immediately thereafter" refers to a period of 1 second to a maximum of 4 hours, preferably from 1 second to 1.5 hours.

[0078] The composition (M) used according to the invention has a pH value in the range of 2.5 to 7.5, preferably in the range of 5.2 to 6.0, particularly preferably in the range of 5.4 to 5.8, in each case at 20°C, and contains the following:

[0079] iii. at least one salt of the divalent iron cation Fe(ll) of an organic carboxylic acid in a total amount of 0.001 - 3.0 wt.%, preferably 0.01 - 2 wt.%, particularly preferably 0.1 - 1 wt.%, extremely preferably 0.2 - 0.5 wt.%, in each case based on the weight of the composition (M),

[0080] iv. optionally a buffer system, selected from a mixture of a moderately strong or weak acid with its conjugate or corresponding base (or the respective salt) and a mixture of a moderately strong or weak base with its conjugate or corresponding acid.

[0081] Another essential ingredient of the dyeing process according to the invention is at least one salt of the divalent iron cation Fe(ll) of an organic carboxylic acid in a total amount of 0.001 - 3.0 wt.%, preferably 0.01 - 2 wt.%, particularly preferably 0.1 - 1 wt.%, and most preferably 0.2 - 0.5 wt.%, in each case based on the weight of the composition (M), wherein no oxidizing agent other than atmospheric oxygen is used in the entire process, and furthermore no elemental iron, sponge iron, copper salts, or aluminum salts are used.

[0082] The sequential application of the Fe(ell) salt of an organic carboxylic acid used according to the invention significantly enhances the intensity of the Coreops / s polyphenol staining. Any yellow tint to the staining is also reduced. According to the invention, "divalent" refers to an iron salt whose cationic component comprises iron in the oxidation state "two".

[0083] According to the invention, carboxylic acid anions that are physiologically compatible are preferred as an anionic counterion for the at least one Fe(ell) salt of an organic carboxylic acid. These preferably include the anions of C1-C6 carboxylic acids that are substituted with one or more hydroxyl groups or that are unsaturated. The anions of lactic acid, gluconic acid, citric acid, acetic acid, propionic acid, oxalic acid, fumaric acid, malonic acid, succinic acid, glutaric acid, galactaric acid (mucus acid), tartaric acid, and malic acid, as well as mixtures of these anions, are particularly preferred as C1-C6 carboxylic acid anions. Lactate is especially preferred.

[0084] Preferred dyeing processes according to the invention are therefore characterized in that the composition (M) as an iron(II) salt of an organic carboxylic acid contains at least one compound selected from iron(II) lactate, iron(II) gluconate, iron(II) citrate, iron(II) acetate, iron(II) propionate, iron(II) oxalate, iron(II) fumarate, iron(II) malonate, iron(II) succinate, iron(II) glutarate, iron(II) galactarate, iron(II) tartrate and iron(II) malate, as well as from mixtures of these salts in a total amount of 0.001 - 3.0 wt.%, preferably 0.01 - 2 wt.%, particularly preferably 0.1 - 1 wt.%, and most preferably 0.2 - 0.5 wt.%, in each case based on the weight of the composition (M).

[0085] If the composition (M) contains several Fe(ell) salts of an organic carboxylic acid, their total amount is 0.001 - 3.0 wt.%, preferably 0.01 - 2 wt.%, particularly preferably 0.1 - 1 wt.%, extremely preferably 0.2 - 0.5 wt.%, in each case based on the weight of the composition (M).

[0086] Particularly preferred dyeing processes according to the invention are characterized in that the composition (M) contains iron(II) lactate as an iron(II) salt in an amount of 0.001 - 3.0 wt.%, preferably 0.01 - 2 wt.%, particularly preferably 0.1 - 1 wt.%, and most preferably 0.2 - 0.5 wt.%, in each case based on the weight of the composition (M).

[0087] Optionally, the composition (M) used according to the invention can include a buffer system as described above for composition (T).

[0088] In compositions (M) preferably used according to the invention, the water content is 40 - 99 wt.%, preferably 50 - 98 wt.%, particularly preferably 60 - 97 wt.%, in each case based on the weight of the composition (M).

[0089] Further staining processes that are particularly preferred according to the invention are characterized in that no basic amino acids are used in the process. It was surprisingly found that the presence of basic amino acids, such as arginine, lysine, histidine, or ornithine in particular, can impair the staining result.

[0090] The composition (M) used according to the invention is free of polyphenols which

[0091] - are available via the shikimat biosynthesis pathway and

[0092] - have at least 2 hydroxy groups in the molecule and a molar mass in the range of 170 to 20,000 g / mol.

[0093] The composition (T) used according to the invention is furthermore free of compounds and salts of transition metal ions. "Free of" in this case means that the composition (T) does not contain any intentionally added compounds and salts of transition metal ions. The content of compounds and salts of transition metal ions that is already naturally present in the water used to produce the composition (T), e.g., tap water or municipal water, is not taken into account; such water is considered, for the purposes of the present invention, to be "free of compounds and salts of transition metal ions".

[0094] The compositions (T) and compositions (M) used and preferably used 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 (T) and compositions (M) adhere better to the hair during application.

[0095] According to the invention, particularly preferred compositions (T) and compositions (M) contain at least one or more hydrophilic thickeners, 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, as well as mixtures thereof.

[0096] 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 compatible salts. In preferred embodiments, xanthan gum is included as a hydrophilic thickener to ensure reliable viscosity adjustment and residue-free application to keratin fibers and the scalp. In further preferred embodiments, carboxymethylcellulose (preferably carboxymethylcellulose with the INCI name Cellulose Gum) is included as a hydrophilic thickener to ensure reliable viscosity adjustment and residue-free application to keratin fibers and the scalp.In a preferred embodiment, carboxymethylcellulose may be included as the sole hydrophilic thickener. A combination of carboxymethylcellulose and hydroxyethylcellulose is particularly preferred. A combination of carboxymethylcellulose and xanthan gum (preferably xanthan gum with the INCI name Xanthan Gum) may also be preferred according to the invention.

[0097] According to the invention, particularly preferred compositions (T) and compositions (M) contain independently of one another 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.%, in each case based on the weight of the respective composition (T) or composition (M).

[0098] In a further preferred embodiment of the present invention, the compositions (T) and compositions (M) used according to the invention each contain, based on their weight, independently of one another 0.1 to 3 wt.%, preferably 0.5 to 2.5 wt.%, more preferably 1.2 to 2.0 wt.%, xanthan gum.

[0099] In a further preferred embodiment of the present invention, the compositions (T) and compositions (M) used according to the invention each contain, based on their weight, independently of one another 0.1 to 4 wt.%, preferably 1 to 2.8 wt.%, carboxymethylcellulose.

[0100] In a further preferred embodiment of the present invention, the compositions (T) and compositions (M) used according to the invention each contain, based on their weight, independently of one another 0.1 to 3 wt.%, preferably 0.5 to 2.5 wt.%, more preferably 1.2 to 2.0 wt.%, hydroxyethylcellulose.

[0101] According to the invention, particularly preferred compositions (T) and compositions (M) 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 (T) contains such an aromatic solvent.

[0102] In a further preferred embodiment of the present invention, the compositions (T) and compositions (M) used according to the invention each contain, based on their weight, independently of one another, 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 (T) and compositions (M) used according to the invention each contain, based on their weight, independently of one another, 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.Particularly preferred dyeing processes according to the invention are characterized in that at least one of the composition (T) or composition (M) independently contains at least one aliphatic solvent selected from Ci-C4 alkanols and C2-C4 polyols, in particular selected from ethanol, isopropanol, n-propanol, ethylene glycol, 1,2-propanediol, glycerol and 1,3-butylene glycol, as well as mixtures of these solvents, but only in a total amount of 0.01 - 8 wt.%, preferably 0.1 - 6 wt.%, particularly preferably 0.5 - 4 wt.%, in each case based on the weight of the composition (T) or the composition (M).

[0103] Other dyeing processes particularly preferred according to the invention are characterized in that neither the composition (T) nor the composition (M) contains an aliphatic solvent selected from Ci-C4 alkanols and C2-C4 polyols.

[0104] In order to make the compositions (T) and (M) used according to the invention also sensorially attractive to the user, further dyeing processes that are particularly preferred according to the invention are characterized in that at least one of the compositions (T) or compositions (M) independently contains at least one perfume oil which contains at least one fragrance compound or odor compound.

[0105] The definition of an odorant within the meaning of the present application corresponds to the skilled-skilled definition as found in the RÖMPP Chemistry Lexicon, dated 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 are a low molar mass of no more than 300 g / mol, a high vapor pressure, minimal water solubility and high lipid solubility, weak polarity, and the presence of at least one osmophoric group in the molecule. To distinguish volatile, low-molecular-weight substances, which are usually not considered odorants but primarily solvents, such as ethanol, propanol, isopropanol, and acetone, from odorants according to the invention,Odorants 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, that is, they excite the receptors of the hair cells of the olfactory system. Examples of ester-type fragrance and odorant compounds are benzyl acetate, phenoxyethyl isobutyrate, p-tert-butylcyclohexyl acetate, linalyl acetate, dimethylbenzylcarbinyl acetate (DMBCA), phenylethyl acetate, benzyl acetate, ethylmethylphenylglycinate, allylcyclohexyl propionate, styralyllipropionate, benzyl salicylate, cyclohexyl salicylate, Floramate, Melusate, and Jasmecyclate. Examples of fragrance and odorant compounds of the ether type are benzyl ethyl ether and ambroxane; examples of fragrance and odorant compounds of the aldehyde type are the linear alkanals with 8–18 carbon atoms, citral, citronellal, citronellyl oxyacetaldehyde, cyclamenaldehyde, lilial, and bourgeonal.Examples of ketone-type fragrance and odor compounds are the ionones, alpha-isomethyl ionone, and methylcedryl ketone; examples of alcohol-type fragrance and odor compounds are anethole, citronellol, eugenol, geraniol, linalool, phenylethyl alcohol, and terpineol; examples of terpene-type fragrance and odor compounds are limonene and pinene. Examples of fragrance and aromatic 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, olibanum 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, and 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, 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 oil, lemon oil, and cypress oil. Other fragrance and odorant compounds include ambrettolide, α-amylcinnamaldehyde, anethole, anisaldehyde, anis alcohol, anisole, methyl anthranilate, acetophenone, benzyl acetone, benzaldehyde, ethyl benzoate, benzophenone, benzyl alcohol, benzyl acetate, benzyl benzoate, benzyl formate, benzyl valerianate, borneol, bornyl acetate, α-bromostyrene, n-decylaldehyde, n-dodecylaldehyde, and 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, camphor, carvacrol, carvone, p-cresol methyl ether, coumarin, p-methoxyacetophenone, methyl n-amyl ketone, methyl anthranilic acid methyl ester, p-methylacetophenone, methyl chavicol, p-methylquinoline, methyl β-naphthyl ketone, methyl n-nonylacetaldehyde, methyl n-nonyl ketone, muscone, β-naphthol ethyl ether, β-naphthol methyl ether, nerol, nitrobenzene, n-nonyl aldehyde Nonyl alcohol, n-octylaldehyde, p-oxyacetophenone, pentadecanolide, β-phenylethyl alcohol, phenylacetaldehyde dimethylacetal, phenylacetic acid, pulegone, safrole, isoamyl salicylate, methyl salicylate, hexyl salicylate, cyclohexyl salicylate, santalol, skatole, terpineol, thymene, thymol, γ-undecalactone, vanillin, veratraldehyde, cinnamaldehydeCinnamyl alcohol, cinnamic acid, ethyl cinnamic acid ester, and benzyl cinnamic acid ester.

[0106] 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.

[0107] Preferably, mixtures of different fragrances are used, which together create an appealing scent.

[0108] Suitable perfume oils can also contain natural fragrance mixtures obtained from plant or animal sources, such as pine, citrus, jasmine, rose, lily, or ylang-ylang oil. Essential oils with lower volatility, which are usually used as aroma components, are also suitable as perfume oils, for example, 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.

[0109] According to the invention, compositions (T) and (M) that are particularly preferred are characterized in that they contain, independently of each other, 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 (T) and composition (M), respectively.

[0110] A further object of the present invention is a kit for the non-oxidative dyeing of keratinous fibers, in particular human hair, with natural dyes, comprising a) an aqueous composition (T) having a pH value in the range of 3.5 to 7.8, preferably in the range of 4.5 to 7.5, particularly preferably in the range of 4.7 to 5.7, in each case measured at 20°C, wherein the composition (T) contains: i. one or more polyphenols that occur naturally in plants of the genus Coreopsis, preferably in plants of the species Coreopsis tinctoria, and that are obtainable via the shikimate biosynthesis pathway and

[0111] - have at least 2 hydroxy groups in the molecule and

[0112] - have a molar mass in the range of 170 to 20,000 g / mol,

[0113] - wherein at least one compound selected from marein and okanin is included as the coreops / s polyphenol; furthermore

[0114] ii. optionally a buffer system selected from a mixture of a moderately strong or weak acid with its conjugate or corresponding base (or the respective salt) and a mixture of a moderately strong or weak base with its conjugate or corresponding acid, and

[0115] b) an aqueous composition (M) having a pH in the range of 2.5 to 7.5, preferably in the range of 5.2 to 6.0, particularly preferably in the range of 5.4 to 5.8, in each case measured at 20°C, wherein the composition (M) comprises: iii. at least one salt of the divalent iron cation Fe(ll) of an organic carboxylic acid in a total amount of 0.001 - 3.0 wt.%, preferably 0.01 - 2 wt.%, particularly preferably 0.1 - 1 wt.%, most preferably 0.2 - 0.5 wt.%, in each case based on the weight of the composition (M),

[0116] iv. optionally a buffer system, selected from a mixture of a moderately strong or weak acid with its conjugate or corresponding base (or the respective salt) and a mixture of a moderately strong or weak base with its conjugate or corresponding acid,

[0117] wherein none of the components of the kit contain oxidizing agents other than atmospheric oxygen, elemental iron, sponge iron, copper salts or aluminum salts. Regarding further preferred embodiments of the kits according to the invention, what has been said about the methods according to the invention and about the compositions (T) and (M) used according to the invention applies mutatis mutandis.

[0118] The following examples are intended to illustrate the subject matter of the invention without limiting it thereto.

[0119] Experimental section

[0120] Comparison between Coreopsis tinctoria staining with post-treatment using organic iron(II) salt (according to the invention) and Coreopsis tinctoria staining with post-treatment using inorganic iron(II) salt (prior art)

[0121] Hair strand coloring with Coreopsis f / ncfor / a extract

[0122] For step a) of the dyeing process, the following composition (T) was prepared (quantities in wt.%):

[0123] Composition (T)

[0124]

[0125] * Coreopsis tinctoria-ExiraM. is a dry extract of the aerial parts of the plant (flowers, buds, leaves, stems, seeds, fruits, seed pods, and fruit peels). It was obtained by aqueous-ethanolic extraction followed by evaporation of the solvent and then homogenized with maltodextrin in a 1:1 weight ratio. The total polyphenol content of the extract is 10.9% in gallic acid equivalents, determined according to the Folin-Ciocalteu method. The marein content is 0.99% w / w, and the flavanomarein content is 0.89% w / w, both based on the total weight of the maltodextrin-containing dry extract.

[0126] For step e) of the dyeing process, the following compositions (M) were prepared (quantities in wt.%): Compositions (M)

[0127]

[0128] All coloring procedures were performed on strands of completely unpigmented Caucasian hair from Kerling International Haarfabrik GmbH (Backnang, Germany). The strands were 10 cm long, of which 8 cm were available for coloring. The remaining 2 cm at the top of the strands served for attachment. Each strand weighed 0.45 ± 0.05 grams. The hair strands were treated for 30 minutes in composition (T) (100 ml / g strand) and then rinsed for one minute under running deionized water, combing 20 times.

[0129] Afterwards, the hair strands were dried with a standard hairdryer at a defined distance (d = 10 cm) and a defined temperature (T = 80 ± 5 °C) by combing 20 times.

[0130] Staining the dyed strands with Fe(ell)

[0131] According to the invention, a portion of the dyed strands was treated with iron(II) lactate. The other portion of the strands dyed with Coreopsis tinctoria was treated with iron(II) sulfate for comparison.

[0132] Post-treatment according to the invention

[0133] Immediately after completion of the drying process, the hair strands dyed with Coreopsis tinctoria were treated in the composition (ME) (100 ml / g strand) for 30 minutes and then rinsed for one minute under running deionized water with 20 combing cycles.

[0134] Comparative follow-up treatment

[0135] Immediately after completion of the drying process, the hair strands dyed with Coreopsis tinctoria were treated for 30 minutes in the composition (Mv) (100 ml / g strand) and then rinsed for one minute under running deionized water with 20 combing strokes. Procedure step f)

[0136] The hair strands treated with Fe(ell) were each dried with a commercially available hair dryer at a defined distance (d = 10 cm) and a defined temperature (T = 80 ± 5 °C) by combing 20 times.

[0137] Spectrophotometric measurement of color loss during washing

[0138] The color difference or color shift, also known as dE or AE, can be determined colorimetrically with a colorimeter that measures the colors in the L*,a*,b* color space, for example with a colorimeter from Datacolor, type Spectraflash SF 600.

[0139] The L*,a*,b* color space refers to the CIELAB color space. The L value represents the brightness of the color (black-white axis); the larger the L value, the brighter the color. The a value represents the red-green axis of the system; the larger this value, the more the color is shifted towards red. The b value represents the yellow-blue axis of the system; the larger this value, the more the color is shifted towards yellow.

[0140] The dyed and Fe(ell)-treated hair strands were colorimetrically measured after drying and compared with the colorimetrically determined Laab values ​​of the undyed strands. All colorimetric measurements of the Laab values ​​were performed using the Spectraflash SF 600 colorimetric instrument from Datacolor.

[0141] The color shift AE, i.e. the color difference between two (hair) colors for which an L*,a*,b* value combination has been determined, is calculated according to the following formula:

[0142] AE = (AL 2 + Aa 2 + From 2 ) 05

[0143] The larger the AE value, the more pronounced the color difference.

[0144] A D65 lamp and a diffuse / 8° optical configuration were used for the spectrophotometer measurements. The spectral reflectance data for each sample from 380 nm to 700 nm were converted into colorimetric data using DCI Color software. Reflectance measurements were determined for each hair sample, with the mean of four measurements recorded.

[0145] For both post-treatment procedures, the color difference (AE) between the dyed, stained strand and the undyed strand was calculated from the measured L a b values ​​according to the following formula:

[0146]

[0147] Lv, av, bv: Colorimetric values ​​of undyed strands

[0148] Ln, an, bn: Colorimetric values ​​after staining and mordant. Results:

[0149] The figure below shows hair colors with Lab coordinates and 21E values. The use of Fe(II) salts generally results in lighter blonde and brown tones, regardless of the counterion. In comparison, the color is more intense and darker when using Fe(II) salts, especially when using Fe(II) lactate. The ZIE value differs by 10 units between Fe(II) lactate and Fe(II) sulfate. The L-coordinate, in particular, is significantly lower in the case of Fe(II) lactate, resulting in a more intense and darker color. This illustrates the advantage of using iron(II) lactate over iron(II) sulfate. The most intense and darkest colors (lowest L-coordinates) are achieved when using Fe(II) gluconate and Fe(II) lactate.

[0150]

[0151] Compared to inorganic ferrous sulfate, organic ferrous salts result in lower L values ​​and higher 21E values. Therefore, darker, more intense colors can be achieved with organic ferrous salts than with inorganic ones. This is particularly true for ferrous lactate. Furthermore, organic ferrous salts result in lower b values ​​compared to inorganic ferrous sulfate, meaning less yellowish coloration. This, too, is especially true for ferrous lactate.

[0152] Influence of the timing of FefID lactate addition on the color result

[0153] The following study investigated whether the timing of the hair strand treatment with Fe(ll)-Lactate influences the coloring result. A distinction was made between pre-, meta-, and post-treatment with Fe(ll)-Lactate, relative to the coloring of the hair strands with Coreopsis tinctoria extract.

[0154] In the pre-coloring process, the hair is first treated for 30 minutes with a 1 wt% aqueous iron(II) lactate solution, then rinsed and dried. In the second step, the hair is colored for 30 minutes with a 1 wt% Coreopsis tinctoria extract in aqueous solution, subsequently rinsed and dried.

[0155] In the meta-coloring process, the hair strand is treated for 30 minutes with an aqueous solution of 1 wt% iron(II) lactate and 1 wt% Coreopsis tinctoria extract. The hair strand is then rinsed and dried.

[0156] The post-coloring process was carried out according to the established method. In the first step, the hair was treated for 30 minutes with a 1% w / w aqueous solution of Coreopsis t / nctor / a extract, then washed and dried. Subsequently, the hair was treated for 30 minutes with a 1% w / w aqueous iron(II) lactate solution, followed by rinsing and drying.

[0157] The strands were then colorimetrically measured and compared with the uncolored strands. The results are summarized in the table below.

[0158]

[0159] The lowest L-values ​​and highest ZIE values ​​were achieved with the post-coloring according to the invention. Particularly dark, intense colors are achieved when the strands already colored with the Coreopsis f / ncto / ' / a extract are treated with Fe(ll)-lactate. Coloring the previously mordanted hair strands (pre-coloring) yields lighter, less intense, and especially more yellow-toned colors.

[0160] The most unfavorable effect on the intensity of the color result is the simultaneous treatment of the strands with Fe(ell)-Lactate and the Coreopsis tinctoria extract.

[0161] Investigations into the influence of wash fastness of dyeing with Coreopsis and Fe(ell) salt post-treatment

[0162] To investigate the wash fastness of a Coreopsis dye and subsequent treatment with an Fe(ll) salt of an organic carboxylic acid, the dyed and Fe(ll)lactate-treated hair strands were shampooed ten times with 0.5 g of shampoo (Schauma 7 Herbs). The hair strands were then rinsed under running water. This process was repeated five more times. Afterward, the hair strands were dried with a hairdryer. This process (six washes) was then repeated three more times, resulting in a total of 24 washes.

[0163] The colorimetric values ​​for the dyed and stained hair strands immediately after dyeing, compared to the color loss after 24 hair washes, are shown in the table below.

[0164] Lab values ​​and the AE values ​​calculated from them, based on untreated hair. Mean values ​​including standard deviation calculated on the basis of three identically colored hair strands.

[0165]

[0166] Twenty-four hair washes resulted in a decrease in color intensity, which was particularly noticeable in the L-value. The a- and b-values ​​remained constant. Consequently, the color shade itself remained unchanged; only the color intensity was reduced by the washes. The ZIE value decreased by 6.7 units.

[0167] Influence of the temperature of staining with Coreopsis on the color intensity

[0168] Hair strands were dyed as described above with a 1 wt% aqueous preparation of Coreopsis tinctura, with some strands dyed at room temperature (20°C) and others at 37°C. Post-treatment with fecal lactate was carried out at room temperature (20°C) in both cases.

[0169] The colorimetric values ​​for the hair strands dyed at two different temperatures are shown in the table below. Lab values ​​and the AE values ​​calculated from them are based on untreated hair. Dyeing with Coreopsis tinctoria extract was carried out at a temperature of 37 °C, followed by the fecal lactate mordant at 20 °C. Mean values, including standard deviation, are calculated based on three identically dyed hair strands.

[0170]

[0171] Staining with Coreopsis tinctoria at a temperature of 37°C followed by iron(ell)-lactate mordant at 20°C results in lower L-values ​​compared to staining and mordanting at 20°C, with a- and b-values ​​showing hardly any changes. The ZIE values ​​are higher in every case than with staining at room temperature.

[0172] Dyeing at 37°C therefore leads to a further significant intensification of the color result.

Claims

Patent claims 1. A process for the non-oxidative dyeing of keratinous fibers, especially human hair, with natural dyes, comprising the following process steps in the specified order: a) Applying an aqueous composition (T) having a pH value in the range of 3.5 to 7.8, preferably in the range of 4.5 to 7.5, particularly preferably in the range of 4.7 to 5.7, each measured at 20°C, to the keratin fibers, wherein the composition (T) comprises the following: i. one or more polyphenols that occur naturally in plants of the genus Coreopsis, preferably in plants of the species Coreopsis tinctoria, and that are available via the shikimate biosynthesis pathway and - have at least 2 hydroxy groups in the molecule and - have a molar mass in the range of 170 to 20,000 g / mol, - wherein at least one compound selected from marein and okanin is included as the coreops / s polyphenol; ii. optionally a buffer system, selected from a mixture of a moderately strong or weak acid with its conjugate or corresponding base (or the respective salt) and a mixture of a moderately strong or weak base with its conjugate or corresponding acid, b) Allow to act for a period of 30 seconds to 60 minutes, preferably 5 to 45 minutes, particularly preferably 15 to 30 minutes, c) Rinsing the keratin fibers with water, d) optional drying of the keratin fibers, e) immediately afterwards applying an aqueous composition (M) having a pH value in the range of 2.5 to 7.5, preferably in the range of 5.2 to 6.0, particularly preferably in the range of 5.4 to 5.8, in each case measured at 20°C, to the keratin fibers, wherein the composition (M) comprises the following: iii. at least one salt of the divalent iron cation Fe(ll) of an organic carboxylic acid in a total amount of 0.001 - 3.0 wt.%, preferably 0.01 - 2 wt.%, particularly preferably 0.1 - 1 wt.%, extremely preferably 0.2 - 0.5 wt.%, in each case based on the weight of the composition (M); iv. optionally a buffer system selected from a mixture of a moderately strong or weak acid with its conjugate or corresponding base (or the respective salt) and a mixture of a moderately strong or weak base with its conjugate or corresponding acid. f) Allow to act for a period of 30 seconds to 60 minutes, preferably 5 to 45 minutes, particularly preferably 15 to 30 minutes, g) Rinsing the keratin fibers with water, h) optionally drying the keratin fibers, the process does not use any oxidizing agent other than atmospheric oxygen, nor any elemental iron, sponge iron, copper salts, or aluminum salts.

2. Staining method according to claim 1, characterized in that, in addition to the at least one coreops / s polyphenol selected from marein and okanin, at least one further coreops / s polyphenol selected from flavanomarein, isokanin, maritimetin, maritimein, coreopsin, quercetagetin-7-O-glycoside, chlorogenic acid, butein, butin, luteolin, eriodictyol, quercetin, sulfuretin, taxifolin, taxifolin-7-O-glucoside, 3,5-dicaffeoylquinic acid, isocoreopsin, isoliquiritigenin and apigenin, as well as mixtures thereof, is included.

3. Dyeing process according to one of claims 1 or 2, characterized in that the at least one Coreops / s polyphenol is contained in the form of at least one ground plant part of the plant genus Coreopsis.

4. Dyeing process according to one of claims 1 or 2, characterized in that the at least one Coreops / s polyphenol is contained in the form of at least one plant part extract of the plant genus Coreopsis.

5. Dyeing process according to any one of claims 1 to 4, characterized in that the at least one Coreops / s polyphenol is derived from a plant selected from the Coreops / s sections Calliopsis, Coreopsis, Electra, Eublepharis, Gyrophyllum, Leptosyne, Pseudoagarista, Pugiopappus, Tuckermannia, Anathysana, Silphidium and the species Coreopsis capillacea and Coreopsis fasciculata.

6. Dyeing process according to any one of claims 1 to 5, characterized in that the at least one Coreops / s polyphenol is derived from a plant selected from Coreopsis tinctoria, Coreopsis basalis, Coreopsis auriculata, Coreopsis grandiflora, Coreopsis intermedia, Coreopsis lanceolata, Coreopsis pubescens, Coreopsis mutica, Coreopsis gladiata, Coreopsis integrifolia, Coreopsis nudata, Coreopsis rosea, Coreopsis major, Coreopsis palmata, Coreopsis pulchra, Coreopsis tripteris, Coreopsis verticillata, Coreopsis californica, Coreopsis latifolia, Coreopsis capillacea and Coreopsis fasciculata.

7. A staining method according to claim 1 or 2, characterized in that the at least one coreops / s polyphenol was produced by a biotechnological process.

8. A staining method according to any one of claims 1 to 7, characterized in that the at least one coreops / s polyphenol was obtained from, optionally genetically modified, plants, animals, fungi, algae or bacteria.

9. Dyeing process according to any one of claims 1 to 8, characterized in that the aqueous composition (T), based on its weight, contains at least one polyphenol in a total amount of 0.001 - 5 wt.%, preferably 0.005 - 1 wt.%, particularly preferably 0.01 - 0.5 wt.%, extraordinarily preferably 0.01 - 0.1 wt.%, including at least one compound selected from marein and okanin.

10. Dyeing process according to any one of claims 1 to 9, characterized in that the composition (T) contains 40 - 99.5 wt.%, preferably 50 - 98 wt.%, particularly preferably 60 - 97 wt.%, extraordinarily preferably 70 - 95 wt.% water, in each case based on the weight of the composition (T), 11. Dyeing process according to one of claims 1 to 10, characterized in that the at least one salt of the divalent iron cation Fe(I) of an organic carboxylic acid applied to the keratin fibers in step e) is selected from iron(I) lactate, iron(I) gluconate, iron(I) citrate, iron(I) acetate, iron(I) propionate, iron(I) oxalate, iron(I) malonate, iron(I) fumarate, iron(I) succinate, iron(I) glutarate, iron(I) galactarate, iron(I) tartrate, iron(I) malate, and from mixtures of these salts.

12. Dyeing process according to any one of claims 1 to 11, characterized in that the aqueous composition (T), in each case based on its weight, contains as a buffer system 0.2 - 1.5 wt.%, preferably 0.3 - 1.4 wt.%, particularly preferably 0.5 - 1.1 wt.%, extraordinarily preferably 0.6 - 0.9 wt.% citric acid and 0.3 - 3.5 wt.%, preferably 0.5 - 3.1 wt.%, particularly preferably 1.0 - 2.4 wt.%, extraordinarily preferably 1.5 - 2.1 wt.% trisodium citrate.

13. Dyeing process according to any one of claims 1 to 12, characterized in that at least one of the compositions (T) or (M) independently contains at least one aliphatic solvent selected from C1-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 solvents, in a total amount of 0.01–8 wt.%, preferably 0.1–6 wt.%, particularly preferably 0.5–4 wt.%, in each case based on the weight of composition (T) or the weight of composition (M).

14. Kit for the non-oxidative dyeing of keratinous fibers, in particular human hair, with natural dyes, comprising a) an aqueous composition (T) having a pH in the range of 3.5 to 7.8, preferably in the range of 4.5 to 7.5, particularly preferably in the range of 4.7 to 5.7, in each case measured at 20°C, wherein the composition (T) contains: i. one or more polyphenols naturally occurring in plants of the genus Coreopsis, preferably in plants of the species Coreopsis tinctoria and - are available via the shikimat biosynthesis pathway and - have at least 2 hydroxy groups in the molecule and - have a molar mass in the range of 170 to 20,000 g / mol; - wherein at least one compound selected from marein and okanin is included as the coreops / s polyphenol; furthermore ii. optionally a buffer system selected from a mixture of a moderately strong or weak acid with its conjugate or corresponding base (or the respective salt) and a mixture of a moderately strong or weak base with its conjugate or corresponding acid, and b) an aqueous composition (M) having a pH value in the range of 2.5 to 7.5, preferably in the range of 5.2 to 6.0, particularly preferably in the range of 5.4 to 5.8, in each case at 20°C, wherein the composition (M) comprises the following: iii. at least one salt of the divalent iron cation Fe(ll) of an organic carboxylic acid in a total amount of 0.001 - 3.0 wt.%, preferably 0.01 - 2 wt.%, particularly preferably 0.1 - 1 wt.%, extremely preferably 0.2 - 0.5 wt.%, in each case based on the weight of the composition (M), iv. optionally a buffer system, selected from a mixture of a moderately strong or weak acid with its conjugate or corresponding base (or the respective salt) and a mixture of a moderately strong or weak base with its conjugate or corresponding acid, none of the kit's components contain oxidizing agents other than atmospheric oxygen, elemental iron, sponge iron, copper salts or aluminum salts.

15. Kit according to claim 14, characterized in that the aqueous composition (T) and the aqueous composition (M) are designed as in any one of claims 2 - 13.

Images