Method of blonding keratinous fibres, comprising the treatment of the keratin fibres with plasma and the use of a blonding agent

Abstract

The present invention provides a method of blonding keratinous fibres, especially human hair, comprising the following steps: (1) treating the keratinous fibres with a plasma, and (2) treating the keratinous fibres with a blonding agent (B), where the blonding agent (B) contains: (B1) hydrogen peroxide, and (B2) at least one peroxodisulfate from the group of ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate.

Description

[0001] A method for bleaching keratin fibers, comprising treating the keratin fibers with plasma and applying a bleaching agent

[0002] The present application relates to a method for bleaching keratin fibers, in particular human hair, which comprises treating the keratin fibers with plasma and applying a bleaching agent (B). The bleaching agent (B) is characterized in that it contains hydrogen peroxide (B1) and at least one peroxodisulfate (B2) from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate, and sodium peroxodisulfate.

[0003] Changing the shape and color of hair represents an important area of ​​modern cosmetics. In addition to coloring, lightening one's hair color, or bleaching, is a particular desire of many consumers, as blonde hair is considered attractive and fashionable. Various bleaching products with varying bleaching power are available for this purpose.

[0004] The oxidizing agents contained in bleaching products are capable of lightening the hair fiber through the oxidative destruction of the hair's natural pigment, melanin. For a moderate bleaching effect, the use of hydrogen peroxide – possibly with the addition of ammonia or other alkalizing agents – as the oxidizing agent alone is sufficient. To achieve a stronger bleaching effect, a mixture of hydrogen peroxide and peroxodisulfate salts and / or peroxomonosulfate salts is usually used.

[0005] For dark hair, longer application times and / or repeated bleaching processes are usually necessary to lighten the hair several shades. However, this also results in more severe damage, as not only the hair's pigments but also the other structural components of the hair are subject to oxidative damage. Depending on the severity of the damage, this can range from rough, brittle, and difficult-to-comb hair to reduced resilience and tensile strength, all the way to hair breakage.

[0006] Various methods for bleaching hair are known in the prior art. However, the known bleaching processes still require improvement, as they generally either describe an improvement in the bleaching effect, which is simultaneously associated with increased damage, or aim to reduce damage, which comes at the expense of the lightening effect. Therefore, the object of the present invention was to find a bleaching process characterized by both improved lightening performance and reduced hair damage. Users who lighten or bleach their hair usually do so at regular intervals to allow the regrowing hair or the roots to adjust to the blonde coloring along the lengths.The longer the user's hair, the more often it is subjected to the bleaching process, so that the associated damage accumulates particularly in the hair lengths.

[0007] It was therefore a further object of the present application to maintain the desired effects, ie the increase in lightening while simultaneously reducing damage, even over the duration of several applications, so that the damage to the hair does not accumulate after repeated bleaching.

[0008] Surprisingly, it has now been found that this object can be excellently achieved if keratinic fibers are bleached or lightened by a process which comprises treating the keratinic fibers with a plasma in step (1) and treating the keratinic fibers with a bleaching agent (B) in step (2), wherein the bleaching agent contains hydrogen peroxide (B1) and at least one peroxodisulfate from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate (B2) as oxidizing agent.

[0009] A first object of the present invention is therefore a method for bleaching keratin fibers, in particular human hair, comprising the following steps:

[0010] (1) Treatment of the keratin fibers with a plasma, and

[0011] (2) Treatment of the keratin fibres with a bleaching agent (B), the bleaching agent (B) containing:

[0012] (B1) hydrogen peroxide, and

[0013] (B2) at least one peroxodisulfate selected from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate.

[0014] The experiments carried out in the course of this application have shown that keratinic fibers such as hair which was subjected to a pre-treatment with a plasma before the application of the bleaching agent (B) were lightened to a greater extent. What was particularly surprising in this context was that this greater lightening was not simultaneously associated with an increase in hair damage, but on the contrary with a reduction in hair damage. This effect was also observed after several times carrying out the method according to the invention, i.e. even after repeated bleaching, the observed effects were still visibly improved compared to the application of the bleaching agent (B) without plasma pre-treatment. Keratinic fibers Keratinic fibers are understood to mean hair, wool or fur. Hair in particular, especially human hair, falls under the definition of keratinic fibers.

[0015] Process for bleaching keratin fibers

[0016] The term "bleaching of keratin fibers" used in the invention can also be synonymously referred to as "lightening of keratin fibers." Bleaching encompasses any form of color change of the fibers in which the keratin fibers have a lighter color than the color they had before the bleaching agent was applied. This particularly includes the color changes encompassed under the terms lightening, bleaching, and bleaching. The lightening of the hair color is achieved by the oxidizing agent(s) present in the product. In addition to the oxidizing agent(s), the products according to the invention can also contain coloring components, such as oxidation dye precursors and / or direct dyes, for the purpose of shading. The coloring components can slightly modify the color loss of the resulting coloration.According to the invention, however, these color-imparting components are contained in the product in such small quantities that the color impression of the keratin fibers treated with the product is still lighter than their original color. Corresponding coloring techniques can be referred to as coloring bleaching or nuanced bleaching.

[0017] The agent used in the bleaching process is the bleaching agent (B), which can also be referred to as a lightening agent.

[0018] Plasma treatment of keratin fibers

[0019] In step (1) of the method according to the invention, the keratin fibers are treated with a plasma. Human hair is particularly preferably treated with the plasma.

[0020] A plasma, within the meaning of the present invention, is understood to be a particle mixture of ions, free electrons, and optionally also neutral atoms and / or molecules. A plasma is characterized by the presence of free charge carriers. A plasma, within the meaning of the present invention, is understood, in particular, to be an ionized gas.

[0021] The degree of ionization of a plasma according to the invention can vary and range, for example, from 0.1 to 100% or even from 1 to 100%. At a degree of ionization of 100%, 100% of the particles are ionized, so in this case, complete ionization occurs. The essential property of a plasma is its electrical conductivity.

[0022] A plasma can be generated, for example, by blowing a working gas at atmospheric pressure (1013 mbar) and atmospheric temperature (20 °C) through an electric arc. When the working gas exits the arc, a so-called plasma jet is created, meaning a gas that is at least partially split into ions and electrons. Gases that can be used include air, helium, or oxygen. In an atmospheric plasma, air is used as the working gas.

[0023] Particularly good results were obtained when the keratin fibers were treated with atmospheric plasma, ie with ionized air, in the process according to the invention.

[0024] In a preferred embodiment, the method according to the invention comprises (1) treating the keratin fibers with atmospheric plasma.

[0025] In a preferred embodiment, the method according to the invention comprises

[0026] (1) Treatment of the keratin fibers with ionized air.

[0027] A cold plasma, or cold atmospheric plasma, is a plasma that does not cause excessive heating of the substrate exposed to the plasma. For example, if keratin fibers are treated with a cold plasma, the keratin fibers do not heat up to physiologically unacceptable temperatures of more than 40°C over the duration of the treatment. To achieve a cold plasma, just enough energy is supplied to the gas (or air) to partially ionize it. For example, many commercially available devices assume 10 9 Only one particle is ionized. Due to the low degree of ionization, the temperature can be controlled so that it remains below 40 °C.

[0028] In a further particularly preferred embodiment, the method according to the invention therefore comprises

[0029] (1) Treatment of the keratin fibers with cold atmospheric plasma.

[0030] In other words, the method according to the invention in this embodiment comprises

[0031] (1) Treatment of the keratin fibers with cold atmospheric plasma, which does not heat the keratin fibers to temperatures above 40 °C during the treatment.

[0032] In principle, there are three families of cold atmospheric plasmas: direct, indirect, and hybrid plasmas. In a direct plasma, the substrate acts as the counter electrode required to generate the plasma. The plasma is therefore generated between the electrode and the substrate. One of the most important direct plasma technologies is the so-called DBD (Dielectric Barrier Discharge) plasma. In an indirect plasma, the plasma is generated between two electrodes and then directed onto the substrate or keratin fibers using a gas stream. An indirect plasma can be generated, for example, using a plasma torch. Hybrid plasmas, so-called corona plasmas, combine the production method of a direct plasma with the properties of indirect plasmas.

[0033] In direct or hybrid plasmas, the keratin fibers act as a counter electrode, and the area under the electrode is treated.

[0034] During the plasma treatment in step (1) of the process, individual sections of the keratin fibers, such as individual strands of hair, can be treated with the plasma, or the plasma treatment can be applied to the entire hair. Treating individual strands with plasma (1) is particularly advantageous for highlight bleaching. In this process, the bleaching agent (B) is preferably applied after the plasma treatment only to the strands that have previously undergone the plasma treatment.

[0035] To perform the treatment, it may be necessary to move the element responsible for the local generation of plasma relative to the keratin fibers or relative to the hair strands. The electrode or plasma generation source is held at a controlled distance from the keratin fibers while being moved across the surface of the keratin fibers. This movement can be performed manually or automatically. In the case of manual movement, it can be assisted by a guide structure placed around the patient's head.

[0036] Commercially available devices can be used to generate plasma, especially cold plasma. With these devices, the plasma can be transported to a nozzle, for example, through a flexible tube. The nozzle, through which the plasma stream flows, can be guided over the keratin fibers to perform the plasma treatment.

[0037] The Plasma Care® device from Terraplasma Medical GmbH is particularly well-suited for the inventive method. Devices in the Plasma Care® product line are handy and designed for mobile use. In this type of device, the plasma source generates plasma through micro-discharges. The plasma source is equipped with very thin ceramic plates and sensitive electrical contacts. A spacer can be placed on the device during each treatment to ensure a controlled, constant distance between the plasma source and the keratin fibers. The device utilizes thin-film technology, which represents a further development of surface micro-discharge technology (SMD). The plasma source unit consists of a high-voltage electrode, a dielectric, and a grounded, structured electrode.By applying a high voltage of 3.5 kV, micro-discharges measuring just a few millimeters are created in the square-structured electrode. These ionize the gas and thus generate plasma. The treatment area that can be covered with the Plasma Care® device is 13 cm. 2 .

[0038] The corresponding device is also described in DE 102018209735 A1, to which reference is made in full at this point.

[0039] The treatment of keratin fibers with plasma is preferably carried out at atmospheric pressure (1,013 x 10 5 Pa).

[0040] In the bleaching process according to the invention, the treatment of the keratin fibers with plasma (1) can be performed at various times. For example, it is possible to subject the still-dry keratin fibers or the still-dry hair to the plasma treatment right at the beginning of the process. Thus, a bleaching process in which dry hair was treated with plasma also resulted in a good lightening effect while simultaneously reducing hair damage.

[0041] However, particularly good lightening results were achieved when the plasma treatment was performed on moistened keratin fibers or moistened or towel-dried hair.

[0042] Damp or towel-dried hair refers to hair that has been completely wetted with water, for example, at the sink or in the shower, then squeezed out and rubbed dry with a towel (e.g., for 30 seconds). Damp or towel-dried hair is therefore no longer dripping wet, but still damp.

[0043] In a further particularly preferred embodiment, the method according to the invention therefore comprises

[0044] (1) Treatment of moistened keratin fibres, in particular moistened hair, with plasma.

[0045] Keratin fibers such as hair that were moistened shortly before application were moistened within a period of no more than 30 minutes, preferably no more than 10 minutes, and most preferably no more than 5 minutes before application.

[0046] In a further particularly preferred embodiment, the method according to the invention therefore comprises

[0047] (1) Treatment of hair with plasma, whereby the hair was moistened shortly before the plasma treatment. The treatment of the keratin fibers with plasma can be carried out over various periods of time. To achieve a significant lightening effect, the keratin fibers can be treated with plasma for a period of 10 seconds to 15 minutes, preferably 20 seconds to 5 minutes, even more preferably 30 seconds to 2 minutes, and most preferably 45 seconds to 90 seconds.

[0048] Treating the keratin fibers with plasma for a period of 30 seconds to 2 minutes, and especially for a period of 45 seconds to 90 seconds, is particularly preferred, as this significantly enhances the lightening effect with a comparatively short application time. Extending the plasma treatment period beyond 2 minutes does further enhance the lightening effect, but the additional lightening that can be achieved by extending the plasma treatment beyond 2 minutes is comparatively small.

[0049] The reduction in hair damage, which is the second major advantage of plasma treatment, is particularly pronounced with treatment times of up to two minutes.

[0050] In a further particularly preferred embodiment, the method according to the invention is therefore characterized by the treatment of the keratin fibers with plasma (1) for a period of 10 seconds to 15 minutes, preferably from 20 seconds to 5 minutes, even more preferably from 30 seconds to 2 minutes and most preferably from 45 seconds to 90 seconds.

[0051] In principle, there are no specifications regarding the sequence of process steps (1) and (2). For example, the keratin fibers can generally first be treated with plasma in the first step (1), after which the bleaching agent (B) is subsequently applied to the keratin fibers in step (2). The reverse sequence, i.e., first bleaching the keratin fibers with the bleaching agent (B) and then treating the already bleached keratin fibers with plasma, is also conceivable in principle. However, the work leading to this invention has shown that very strong lightening could be achieved, especially when the keratin fibers were treated with plasma as a pretreatment before the subsequent bleaching step with the bleaching agent (B). In particular, the hair damage observed when hair was first treated with cold, atmospheric plasma and then lightened with the bleaching agent (B), was greatly reduced.

[0052] Therefore, a method for bleaching keratin fibers, in particular human hair, is particularly preferred, comprising the following steps in the given order: (1) Treatment of the keratin fibers with a plasma, particularly preferably with cold, atmospheric plasma, and then the

[0053] (2) Treatment of the keratin fibres with a bleaching agent (B), the bleaching agent (B) containing:

[0054] (B1) hydrogen peroxide, and

[0055] (B2) at least one peroxodisulfate selected from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate.

[0056] In principle, the process according to the invention is not subject to any restrictions with regard to the time periods that may lie between steps (1) and (2). From a practical point of view, however, steps (1) and (2) are carried out within a bleaching process that is completed within a period of a few hours. For this reason, it is preferred if the time period between steps (1) and (2) is a maximum of 72 hours, preferably a maximum of 48 hours, more preferably a maximum of 24 hours, even more preferably a maximum of 2 hours, and most preferably a maximum of 30 minutes.

[0057] The tests carried out also showed that bleaching with good results was achieved, in particular, when there was a period of maximum 72 hours, preferably maximum 48 hours, more preferably maximum 24 hours, even more preferably maximum 2 hours and most preferably maximum 30 minutes between the plasma treatment in step (1) and the bleaching step (2).

[0058] In a further embodiment, a method comprising (1) treating the keratin fibers with plasma in a first step, followed by (2) treating the keratin fibers with the bleaching agent (B) in a second step, wherein between steps (1) and (2) there is a period of a maximum of 72 hours, preferably a maximum of 48 hours, more preferably a maximum of 24 hours, even more preferably a maximum of 2 hours and most preferably a maximum of 30 minutes.

[0059] Bleaching agent (B) for bleaching or lightening keratin fibers

[0060] In step (2) of the process according to the invention, the keratin fibers are treated with the bleaching agent (B). The bleaching agent (B) is characterized in that it contains hydrogen peroxide (B1) and at least one peroxodisulfate (B2) from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate, and sodium peroxodisulfate.

[0061] For the purposes of the present application, bleaching agent (B) is understood to mean a ready-to-use bleaching agent that can be applied directly to the keratin fibers in its present form. The oxidizing agent types contained in the bleaching agent, i.e., hydrogen peroxide and peroxodisulfate, can be prepared separately before use for stability and compatibility reasons. Thus, the ready-to-use bleaching agent can also be prepared before use by mixing at least two separate preparations, the first preparation containing hydrogen peroxide (B1) and the second preparation containing the peroxodisulfate salt(s) (B2).

[0062] Hydrogen peroxide (B1)

[0063] The bleaching agent used in the process according to the invention contains hydrogen peroxide (B1) as the first essential oxidizing agent.

[0064] In a preferred embodiment, hydrogen peroxide itself is used as an aqueous solution. The concentration of a hydrogen peroxide solution in the ready-to-use bleaching agent (B) according to the invention is determined, on the one hand, by legal requirements and, on the other hand, by the desired effect. Preferably, 3 to 12 wt.% solutions in water are used and diluted accordingly to achieve the desired concentration in the ready-to-use bleaching agent (B).

[0065] Methods preferred according to the invention are characterized in that the keratin fibers are treated in step (2) with a bleaching agent (B) which - based on the total weight of the bleaching agent (B) - contains 0.1 to 12.0 wt.%, preferably 0.5 to 10.5 wt.%, more preferably 1.0 to 5.5 wt.%, even more preferably 1.2 to 5.5 wt.% and very particularly preferably 3.5 to 4.5 wt.% hydrogen peroxide (B1).

[0066] In this context, it was discovered that the concentration of hydrogen peroxide (B1) in the ready-to-use bleaching agent can have a significant influence on the simultaneous increase in lightening and reduction in damage. Studies of bleaching agents with different hydrogen peroxide concentrations have shown that, with the same peroxodisulfate content (B2), the lightening performance initially increases with increasing hydrogen peroxide concentration (B1). The increase in lightening with an increase in the amount of oxidizing agent is not initially surprising to those skilled in the art. What was surprising, however, was that a particularly strong reduction in hair damage occurred at a hydrogen peroxide content of 1.2 wt.% and above, with a peak at 4 wt.%.

[0067] When a bleaching agent with a hydrogen peroxide content of 1.2 to 5.5 wt.%, in particular 3.5 to 4.5 wt.%, was applied in the process according to the invention, the lightening was very strong, and at the same time, hair damage decreased compared to conventional bleaching without plasma pretreatment. When the hydrogen peroxide content was increased further to 6 wt.%, the lightening performance was further improved, but hair damage also increased slightly compared to conventional bleaching. A bleaching agent (B) with 1.2 to 5.5 wt.%, in particular 3.5 to 4.5 wt.% hydrogen peroxide (B1) therefore contains the oxidizing agent in the amount range that can simultaneously improve the lightening performance and reduce hair damage after the plasma pretreatment.

[0068] Within the scope of a further embodiment, a process according to the invention is very particularly preferred, comprising the use of a bleaching agent (B) which - based on the total weight of the bleaching agent (B) - contains 0.1 to 12.0 wt.%, preferably 0.5 to 10.5 wt.%, more preferably 1.0 to 5.5 wt.%, even more preferably 1.2 to 5.5 wt.% and very particularly preferably 3.5 to 4.5 wt.% hydrogen peroxide (B1).

[0069] Peroxodisulfates (B2)

[0070] As a second essential oxidizing agent, the bleaching agent (B) used in the process according to the invention contains at least one peroxodisulfate from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate.

[0071] Ammonium peroxodisulfate, which can also be called ammonium persulfate, is the persulfate with the molecular formula (NH4)2S2Oa.

[0072] Potassium peroxodisulfate, which can also be called potassium persulfate, is the persulfate with the molecular formula K2S2O8.

[0073] Sodium peroxodisulfate, which can also be called sodium persulfate, is the persulfate with the molecular formula Na2S2Os.

[0074] Very good results were obtained with bleaching agents containing ammonium peroxodisulfate and / or potassium peroxodisulfate.

[0075] In a further embodiment, a method according to the invention is preferred, comprising the treatment (2) of the keratin fibers with a bleaching agent (B) containing (B2) ammonium peroxodisulfate and / or potassium peroxodisulfate.

[0076] Particularly good results were obtained with bleaching agents containing the combination of ammonium peroxodisulfate and potassium peroxodisulfate.

[0077] Within the scope of a further embodiment, a method according to the invention comprising the treatment (2) of the keratin fibers with a bleaching agent (B) containing (B2) ammonium peroxodisulfate and potassium peroxodisulfate is particularly preferred. The persulfate(s) are also preferably used in specific amounts in the bleaching agent (B). It has been found to be preferable if the bleaching agent (B)

[0078] - based on the total weight of the bleaching agent (B) - one or more peroxodisulfates from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate in a total amount of 2.0 to 40.0 wt.%, preferably 7.0 to 30.0 wt.%, more preferably 9.0 to 20.0 wt.% and very particularly 11.0 to 16.0 wt.%.

[0079] Within the scope of a further embodiment, a method according to the invention is particularly preferred, comprising the treatment (2) of the keratin fibers with a bleaching agent (B) which

[0080] - based on the total weight of the bleaching agent (B) - one or more persulfates from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate in a total amount of 2.0 to 40.0 wt.%, preferably 7.0 to 30.0 wt.%, more preferably 9.0 to 20.0 wt.% and very particularly 11.0 to 16.0 wt.%.

[0081] Other optional ingredients of the bleaching agent (B)

[0082] In addition to the essential ingredients (B1) and (B2), the bleaching agent may optionally also contain other ingredients.

[0083] The bleaching agent (B) may preferably additionally contain at least one alkalizing agent. If the ready-to-use bleaching agent is prepared by mixing at least two separate preparations prior to use, the alkalizing agent can, for example, be incorporated into the preparation together with the peroxodisulfates (B2) or can be present separately from the hydrogen peroxide (B1) and peroxodisulfates (B2) in a third, separate preparation.

[0084] Preferred alkalizing agents include ammonia, alkanolamines, basic amino acids, and inorganic alkalizing agents such as alkaline earth metal hydroxides, alkaline earth metal metasilicates, alkaline earth metal silicates, alkaline earth metal phosphates, and alkaline earth metal hydrogenphosphates. Lithium, sodium, and / or potassium are preferred metal ions. Preferred alkalizing agents are alkaline earth metal metasilicates and alkaline earth metal silicates.

[0085] Suitable inorganic alkalizing agents are preferably selected from sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, sodium phosphate, potassium phosphate, sodium silicate, potassium silicate, magnesium silicate, sodium carbonate, and potassium carbonate. Sodium hydroxide and / or potassium hydroxide are particularly preferred.

[0086] Alkanolamines as alkalizing agents are preferably selected from primary, secondary or tertiary amines having a C2-Ce-alkyl parent structure carrying at least one hydroxyl group. Particularly preferred alkanolamines are selected from the group consisting of 2-aminoethan-1-ol (monoethanolamine), 3-aminopropan-1-ol, 4-aminobutan-1-ol, 5-aminopentan-1-ol, 1-aminopropan-2-ol (monoisopropanolamine), 1-aminobutan-2-ol, 1-aminopentan-2-ol, 1-aminopentan-3-ol, 1-aminopentan-4-ol, 2-amino-2-methylpropanol, 2-amino-2-methylbutanol, 3-amino-2-methylpropan-1-ol, 1-amino-2-methylpropan-2-ol, 3-aminopropan-1,2-diol, 2-amino-2-methylpropan-1,3-diol, 2-amino-2-ethyl-1,3-propanediol, N,N-Dimethylethanolamine, methylglucamine, triethanolamine, diethanolamine, and triisopropanolamine. Particularly preferred alkanolamines are monoethanolamine, 2-amino-2-methylpropanol, and triethanolamine.

[0087] Basic amino acids as alkalizing agents are preferably selected from the group consisting of L-arginine, D-arginine, D / L-arginine, L-lysine, D-lysine, D / L-lysine, L-ornithine, D-ornithine, D / L-ornithine, L-histidine, D-histidine, and / or D / L-histidine. L-arginine, D-arginine, and / or D / L-arginine are particularly preferably used as an alkalizing agent.

[0088] For shading purposes, the bleaching agent may also contain at least one oxidation dye precursor and / or at least one direct dye.

[0089] Furthermore, the bleaching agent (B) can also contain other active ingredients, auxiliaries and additives, such as complexing agents, solvents, fatty components such as Ca-Cso fatty alcohols, Ca-Cso fatty acid triglycerides, Ca-Cso fatty acid monoglycerides, Ca-Cso fatty acid diglycerides and / or hydrocarbons; non-ionic surfactants, anionic surfactants, cationic surfactants, amphoteric and / or zwitterionic surfactants, polymers; structuring agents such as glucose, maleic acid and lactic acid, hair conditioning compounds such as phospholipids, for example lecithin and cephalins; perfume oils, dimethyl isosorbide and cyclodextrins; fiber structure-improving active ingredients, in particular mono-, di- and oligosaccharides such as glucose, galactose, fructose, fructose and lactose; dyes for coloring the agent; Anti-dandruff agents such as piroctone olamine, zinc omadine, and climbazole; amino acids and oligopeptides;Protein hydrolysates of animal and / or plant origin, as well as in the form of their fatty acid condensation products or, where appropriate, anionically or cationically modified derivatives; vegetable oils; sunscreens and UV blockers; active ingredients such as panthenol, pantothenic acid, pantolactone, allantoin, pyrrolidinonecarboxylic acids and their salts, and bisabolol; polyphenols, in particular hydroxycinnamic acids, 6,7-dihydroxycoumarins, hydroxybenzoic acids, plant extracts; fats and waxes such as fatty alcohols, beeswax, montan wax, and paraffins; swelling and penetrating agents such as glycerol, propylene glycol monoethyl ether, carbonates, hydrogen carbonates, guanidines, ureas, and primary, secondary, and tertiary phosphates; opacifiers such as latex, styrene / PVP, and styrene / acrylamide copolymers; Pearlescent agents such as ethylene glycol mono- and distearate and PEG-3 distearate; as well as propellants such as propane-butane mixtures, N2O, dimethyl ether, CO2 and air.

[0090] The expert will select these additional substances based on the desired properties of the agent. Regarding further optional components and the amounts of these components used, reference is expressly made to the relevant manuals known to the expert. The additional active ingredients and excipients are preferably used in the preparations according to the invention in amounts of 0.0001 to 25 wt.%, in particular 0.0005 to 15 wt.%, based on the total weight of the respective agent.

[0091] Application of the bleaching agent (B)

[0092] For the treatment (2) of the keratin fibers with a bleaching agent (B), the bleaching agent (B) is applied to the keratin fibers, left to act on the keratin fibers for a period of 1 to 60 minutes, preferably 15 to 55 minutes and most preferably 30 to 50 minutes, and then rinsed out again with water.

[0093] Within the scope of a further embodiment, a method according to the invention is particularly preferred, comprising the treatment (2) of the keratin fibers with a bleaching agent (B), wherein

[0094] (21) the bleaching agent (B) is applied to the keratin fibres,

[0095] (22) for a period of 1 to 60 minutes, preferably 15 to 55 minutes and most preferably 30 to 50 minutes, on the keratin fibres, and then

[0096] (23) is rinsed out.

[0097] The bleaching agent can be rinsed out with water or with water and a shampoo containing surfactants.

[0098] In a post-treatment step, a conditioner can optionally be applied.

[0099] Repeating the bleaching process

[0100] When a user decides to lighten their hair, they typically want a permanent blonde tone and therefore repeat the bleaching process at regular intervals. With each subsequent bleaching, the hair experiences additional damage, so reducing hair damage, which persists even after multiple bleaching sessions, is particularly important for the user.

[0101] The tests conducted within the scope of this application have shown that the reduction in damage achieved by implementing the method according to the invention is measurable, particularly after multiple bleachings. For this reason, the method according to the invention offers a particular advantage when applied to previously bleached hair, or when the method itself is repeated several times. Within the scope of a further embodiment, a method according to the invention comprising the following steps in the following order is particularly preferred:

[0102] (1) Treatment of already bleached keratin fibers with a plasma, and

[0103] (2) Treatment of the keratin fibers with the bleaching agent (B).

[0104] Keratin fibers or hair that has already been bleached have previously been treated by the user or hairdresser with a lightening agent for the keratin fibers or hair. This lightening or bleaching agent contained hydrogen peroxide and one or more peroxydisulfates. The previous bleaching can, for example, have taken place a few days to 12 weeks before performing the method according to the invention. The exact time after which the bleaching is repeated depends, among other things, on the desired shade of blonde and the user's willingness to tolerate a darker, regrown hairline.

[0105] In a further embodiment, a method for bleaching keratin fibers, in particular human hair, comprising the following steps is also preferred:

[0106] (1) Treatment of the keratin fibers with a plasma, and

[0107] (2) Treatment of the keratin fibres with a bleaching agent (B), the bleaching agent (B) containing:

[0108] (B1) hydrogen peroxide, and

[0109] (B2) at least one peroxodisulfate from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate, wherein steps (1) and (2) are repeated at least once within a period of 1 day to 12 weeks.

[0110] Within this latter embodiment, the method according to the invention is thus carried out twice within a period of 1 day to 12 weeks.

[0111] Examples

[0112] 1 . Recipes

[0113] The following formulations were prepared. All data are in wt.% unless otherwise stated.

[0114] Developer formulations (Table 1)

[0115] Bleaching powder (Table 2)

[0116] 2. Preparation of the ready-to-use bleaching agent (B)

[0117] The ready-to-use bleaching agents (B) were prepared by mixing two parts by weight of developer with one part by weight of bleaching powder. The ready-to-use bleaching agents have the hydrogen peroxide and peroxodisulfate contents indicated in the table. Ready-to-use bleaching agents (Table 3)

[0118] 3. Bleaching process

[0119] Dark brown hair strands (Kerling 9-0) were colorimetrically measured using a Datacolor Spectraflash 450 colorimeter. Shortly before treatment, the hair strands were thoroughly wetted with water and towel-dried until they were towel-damp. Immediately afterward, the towel-damp strands were treated with plasma for 60 seconds (1 minute) or 300 seconds (5 minutes). For this, the Plasma Care® device from Terraplasma Medical GmbH was placed on the hair strand and switched on for the above-mentioned time period.

[0120] Immediately after the plasma treatment, the strands were bleached with the respective bleaching agent. The bleaching agent was applied to the strand and left to work for 45 minutes at room temperature (25°C). Following this, the strand was thoroughly rinsed with water (1 minute) and dried.

[0121] For comparison, hair strands (Kerling 9-0) were colorimetrically measured using a Datacolor Spectraflash 450 colorimeter, moistened, and then bleached using the bleaching agent (B) according to the above procedure, without plasma treatment. After bleaching and drying, the hair strands were colorimetrically measured again.

[0122] To assess the brightening performance, the dE value was used, which is calculated from the measured L*a*b* color values ​​as follows: dE = [ (Li - Lo) 2 + (ai - ao) 2 + (bi - bo)] 1 / 2

[0123] Lo, ao and bo = measurements of the untreated hair strand

[0124] Li, ai and bi = measurements of the hair strand after treatment

[0125] The higher the dE value, the greater the color difference to untreated hair.

[0126] If a double bleaching was to be investigated, the respective bleaching procedure was carried out twice on the hair strand.

[0127] 4. Measurement of hair damage

[0128] The hair lightened with the various bleaching methods was examined for hair damage. For this purpose, the amount of cysteic acid present in the hair strand was determined using quantitative NIR spectroscopy.

[0129] The spectra were recorded with an MPA™ FT -NIR spectrometer from Bruker Optik GmbH. The infrared range covers the wavenumber range of 12500 cm -1 up to 4000 cm -1 and is characteristic of overtone and combination vibrations of, for example, CH, OH and NH groups.

[0130] The measurements were carried out using the integrating sphere module at six different sample positions in diffuse reflection. For the analysis of the measured NIR spectra, the wavenumber range of 7300 cm -1 up to 4020 cnr 1 chosen.

[0131] The NIR spectra of cystine show in the wavenumber range of 6200 cm -1 up to 5500 cm -1 characteristic absorption bands. If the hair changes due to more severe damage (ie the cysteic acid content in the hair increases), this affects the bands in the NIR spectrum that are characteristic of cysteic acid at 5020 cm -1 up to 4020 cm -1 The quantitative analysis of the NIR spectra was carried out using computer-aided methods.

[0132] The NIR analysis value provides the amount of mol of cysteic acid per 100 mol of amino acid. The higher this cysteic acid value, the more severe the hair damage:

[0133] 5. Results

[0134] The following values ​​were obtained: Two bleaching cycles (Table 4) in [mol cysteic acid / 100 mol amino acid]

[0135] V = Comparison

[0136] E = according to the invention

[0137] Table 4 lists the bleaching results and hair damage after two bleaching sessions. For example, in bleaching treatment E1, steps (1) and (2) were performed, the hair was left to rest for 1 day, and then both steps (1) and (2) were repeated. In bleaching treatment V1, step (2) was performed twice. Compared to V1, E1 showed an improvement in bleaching performance while simultaneously reducing hair damage.

[0138] Compared to V2, E2 showed an improvement in bleaching performance while reducing hair damage.

[0139] With E3, the bleaching performance was improved compared to V3, but hair damage also increased slightly.

[0140] E2 / V2 showed a greater improvement in lightening compared to E1 / V1. In the test series shown in Table 4, the best results were obtained with the E2 bleaching method.

[0141] One-time bleaching (Table 5) in [mol cysteic acid / 100 mol amino acid]

[0142] Table 5 lists the bleaching values ​​and hair damage after a single bleaching with the bleaching agent (B2).

[0143] Compared to V4, E4 showed an improvement in bleaching performance while reducing hair damage.

[0144] In E5, the plasma treatment was extended from 1 minute to 5 minutes compared to E4. E5 showed an improvement in lightening compared to V4, but the lightening performance could not be further improved by extending the plasma treatment time from 1 to 5 minutes. In the test series shown in Table 5, the best results were obtained with the E4 bleaching process.

Claims

Patent claims 1. A process for bleaching keratin fibers, in particular human hair, comprising the following steps: (1) Treatment of the keratin fibers with a plasma, and (2) Treatment of the keratin fibres with a bleaching agent (B), the bleaching agent (B) containing: (B1) hydrogen peroxide, and (B2) at least one peroxodisulfate selected from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate.

2. Method according to claim 1, comprising the (1) Treatment of the keratin fibers with cold atmospheric plasma.

3. Method according to one of claims 1 to 2, comprising (1) treating moistened keratin fibers, in particular moistened hair, with plasma.

4. Method according to one of claims 1 to 3, characterized by the treatment of the keratin fibers with plasma (1) for a period of 10 seconds to 15 minutes, preferably from 20 seconds to 5 minutes, even more preferably from 30 seconds to 2 minutes and most preferably from 45 seconds to 90 seconds.

5. The method according to any one of claims 1 to 4, comprising (1) treating the keratin fibers with plasma in a first step, followed by (2) treating the keratin fibers with the bleaching agent (B) in a second step, wherein between steps (1) and (2) there is a period of a maximum of 72 hours, preferably a maximum of 48 hours, more preferably a maximum of 24 hours, even more preferably a maximum of 2 hours and most preferably a maximum of 30 minutes.

6. The method according to any one of claims 1 to 5, comprising the use of a bleaching agent (B) which - based on the total weight of the bleaching agent (B) - contains 0.1 to 12.0 wt.%, preferably 0.5 to 10.5 wt.%, more preferably 1.0 to 5.5 wt.%, even more preferably 1.2 to 5.5 wt.% and most preferably 3.5 to 4.5 wt.% hydrogen peroxide (B1).

7. Method according to one of claims 1 to 6, comprising the treatment (2) of the keratin fibers with a bleaching agent (B) containing (B2) ammonium peroxodisulfate and potassium peroxodisulfate.

8. The method according to any one of claims 1 to 7, comprising the treatment (2) of the keratinic fibers with a bleaching agent (B) which - based on the total weight of the bleaching agent (B) - contains one or more peroxodisulfates from the group consisting of ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate in a total amount of 2.0 to 40.0 wt.%, preferably of 7.0 to 30.0 wt.%, more preferably of 9.0 to 20.0 wt.% and very particularly of 11.0 to 16.0 wt.%.

9. Method according to one of claims 1 to 8, comprising the treatment (2) of the keratin fibers with a bleaching agent (B), wherein (21) the bleaching agent (B) is applied to the keratin fibres, (22) for a period of 1 to 60 minutes, preferably 15 to 55 minutes and most preferably 30 to 50 minutes, on the keratin fibres, and then (23) is rinsed out.

10. Method according to one of claims 1 to 9, comprising the following steps in the following order: (1) Treatment of already bleached keratin fibers with a plasma, and (2) Treatment of the keratin fibers with the bleaching agent (B).

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