BLEACHING FOILS

Abstract

Foil applicators for selective lightening of keratinic fibers and methods for selective lightening of keratinic fibers are provided. In an embodiment, a foil applicator contains a first layer comprising a leaf-like substrate and a second layer comprising a bleaching preparation containing a solid peroxodisulfate salt applied to the leaf-like substrate. The bleaching preparation is embedded in a nonwoven supporting material.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation of International Application No. PCT/EP2011/053436, filed Mar. 8, 2011, which was published under PCT Article 21(2) and which claims priority to German Application No. 102010029206.0, filed May 21, 2010, which are all hereby incorporated in their entirety by reference.

TECHNICAL FIELD

The technical field relates to a foil-like applicator for the selective color lightening of keratinic fibers, in particular human hair, and to methods for producing selective lightening effects on human head hair with such foil applicators.

BACKGROUND

Changing one's outward appearance, in particular changing the color of one's head hair, is an enduring fashion requirement in society. In addition to coloring the hair, lightening the hair is of particular interest to the user. For that reason lightening agents are in widespread use, either in the hairdressing sector or by home application. A number of problems arise when coloring the hair—in particular when coloring the hair by home application. Firstly, natural color shades are completely covered up, making multi-tonal colors difficult to achieve. Secondly, the selective lightening of individual sections of the hair, such as fiber bundles, strands and partings for example, is difficult to achieve without suitable aids. The use of suitable aids such as applicators or brushes frequently demands considerable experience and skill, however.

To give the hair a more natural appearance, undyed or dyed hairs are conventionally partially decolorized by the targeted application of oxidizing agents. Selected sections of the hair (“highlights”) to which the oxidizing agent preparation is applied fade during this process, giving rise to a multi-tonal hair color. The oxidizing agent preparation is applied using a brush or applicator, the hair to be treated optionally being selected by means of aluminum foil or a “highlighting cap”.

The problem with this procedure is that to produce the actual lightening preparation, a bleaching powder is usually mixed with an oxidizing agent preparation first and then strands and foils have to be wetted. In addition, it is often difficult to estimate the amount of application mixture required, so fresh mixture has to be prepared subsequently or surplus mixture discarded.

Therefore in the prior art, in particular WO1993/010687A1, the use of highlighting foils or highlighting papers to produce highlights has been proposed. These are flexible substrates impregnated with an activator encompassing ammonia or ammonium salts and optionally coloring agents and foaming agents. The impregnated substrates are treated before use with an oxidizing agent containing hydrogen peroxide in order to produce the actual lightening preparation and applied by wrapping them around the strand to be lightened.

Mixing on the foil presents a number of disadvantages for the user. Firstly it must be ensured that all foils are treated with the same amount of oxidizing agent. Secondly, after mixing the oxidizing agent preparation, the time within which it can be applied to the strand is limited. However, different preparation compositions and/or varying application time periods can lead to undesirable and uneven lightening results. There is therefore still a need, in particular for inexpert users, for easy-to-use applicator forms for the selective lightening of sections of the hair, in particular for producing highlights.

Finally the use of hydrogen peroxide alone is often not sufficient to achieve a satisfactory lightening result, in particular on dark hair. To improve the lightening result, bleach boosters are frequently added to bleaching agents. Peroxo salts are particularly suitable as bleach boosters, in particular peroxodisulfates. Owing to their salt form, however, there are limits to the extent to which these substances can be attached to a substrate or impregnated into a substrate without the solid peroxo salts crumbling when the foil is folded, reducing the bleaching power. There is also the risk that these salts will become detached when the foil is wrapped around the strand, resulting in pronounced bleaching agent gradients within the wrap.

SUMMARY

At least one object herein is therefore to provide bleaching agents in an applicator form that firstly is easy to use. Secondly, these bleaching agents should enable uniform and improved lightening results to be obtained, even on dark hair. The lightening agents should be applied to a flexible substrate in such a way that the agents do not detach when the substrate is folded, rolled or shaped in any other way. Finally these lightening agents should avoid the need for the laborious subsequent preparation of additional application mixture or the discarding of surplus mixture.

It has now been found that a special applicator in foil form can advantageously be used for the targeted and selective application of lightening agents if the applicator is a foil onto which a nonwoven supporting material has been applied in which a peroxodisulfate salt has been incorporated.

This form of foil applicator differs advantageously from the prior art in that a markedly improved lightening performance can be achieved. The nonwoven supporting material that is applied allows the peroxodisulfate salts to be embedded without detaching, maintaining the flexibility of the foil, and because of its structure it ensures that liquid penetrates easily into the supporting material, thus dissolving the bleach booster.

DETAILED DESCRIPTION

Therefore firstly provided is a foil applicator for the selective lightening of keratinic fibers, encompassing

• • (i) a leaf-like substrate (A) as the first layer and
  • (ii) a cosmetic bleaching preparation (B) containing at least one solid peroxodisulfate salt applied to the leaf-like substrate (A) as the second layer,
    wherein the bleaching preparation (B) is embedded in a nonwoven supporting material.

The terms “foil applicator”, “highlighting foil” and “applicator” are used synonymously below.

The applicator according to an embodiment encompasses a flexible substrate. The flexible substrate can assume any shape and consist of any material or any mixture of materials that is flexible. “Flexible” within the meaning contemplated herein refers to substrates that in terms of shape and materials are structured in such a way that they can be shaped by manual force, with reversible shaping being preferred. The flexible substrates according to an embodiment are leaf-like or laminar. “Leaf-like” or “laminar” as used herein means that the spatial extent of the substrate in one spatial direction is markedly smaller than in the other two spatial directions, wherein the smallest spatial extent of the substrate in the context herein is described as the “height” or “thickness”, while the corresponding extent of the substrate in the two orthogonal spatial directions is described as the “width” and “length”. These spatial directions fix the surface dimensions of the layer. If the spatial extent of the substrate in the spatial directions that are orthogonal to the height differs, then in the context herein the smaller spatial extent is described as the “width”, the larger as the “length”.

In substrates according to an exemplary embodiment the ratio of width to height is about 10 to about 1 to about 100,000 to about 1, for example about 50 to about 1 to about 50,000 to about 1, such as about 100 to about 1 to about 1000 to about 1. In one embodiment leaf-like substrates have the characterizing feature that their height is about 1 to about 1000 μm, for example about 2.5 to about 500 μm, such as about 4 to about 250 μm. Length and width of exemplary leaf-like substrates are in the range of from about 1 to about 50 cm, for example from about 2 to about 40 cm, for example from about 3 to 35 cm, such as from about 4 to about 30 cm.

Another embodiment of the foil applicator has the characterizing feature that the leaf-like substrate (A) has a thickness of from about 0.5 μm to about 1 mm, for example of from about 1 μm to about 0.5 mm, for example from about 1.5 μm to about 0.1 mm, such as from about 20 μm to about 0.1 mm.

With a view to a stable shaping in the lightening process and taking account of the fact that the leaf-like substrate (A) should be able to be wrapped stably around a hair strand with no further mechanical aids, the use of aluminum foils is particularly suitable. Laminates in which the individual layers are glued to one another are suitable in particular.

In an exemplary embodiment, foil applicators contemplated herein have the characterizing feature that the leaf-like substrate (A) is an aluminum foil.

A cosmetic bleaching preparation (B) that is embedded in a nonwoven supporting material is applied to the leaf-like substrate.

A nonwoven fabric is understood herein to be a static accumulation of fibers, which depending on the production method leads to a differently consolidated material. The density of the fibers of the nonwoven fabric critically determines inter alia the rate of water ingress and egress into and out of this layer. A nonwoven fabric whose density ensures good water ingress and egress is preferred.

Various materials are suitable as the fiber material of the nonwoven fabric. For example, natural fibers such as pulp or cotton fibers, synthetic fibers such as polyester, polyamide, polypropylene or polyethylene, or bicomponent fibers in which natural and synthetic materials have been combined, such as for example pulp in combination with polyethylene, are suitable.

As the nonwoven supporting materials should be as chemically inert as possible under the oxidative, conventionally highly alkaline application conditions of bleaching, fibers having the corresponding stability are suitable. Nonwoven supporting materials made from fibers of polypropylene and moreover of polyethylene, polyesters, viscose, as well as acrylic fibers and polyamide fibers, are examples of suitable materials. Nonwoven supporting materials made from fibers of polypropylene are particularly suitable.

The fiber materials can be produced by various methods, such as for instance the known wet-laid, dry-laid, melt-blow, spun-laid or air-laid technologies. The nonwoven fabric is formed from the optionally roughened (carded) fibers by consolidation by means of mechanical needling (needle-punched nonwoven), spunlacing (water jet consolidation) or spunbonding (thermal, UV or IR consolidation, optionally involving gluing with certain aqueous dispersions such as polyacrylates, polyvinyl acetates, polybutadienes, latex and butadiene-styrene copolymers).

Such nonwovens are known inter alia from cleaning cloths or cosmetic cloths but also from other areas such as liquid or gas filter technology.

It has proved useful to give the nonwoven supporting material a hydrophilic finish in order to improve and accelerate the absorption of water during application, allowing the peroxodisulfate salts to be used more quickly and more completely. Finishing within the context herein is understood to mean a chemical and/or physical change of the supporting material, which provides it with certain performance characteristics, in the present case improved water absorption. The supporting materials are, for example, finished with anionic surfactants. This type of finishing simultaneously provides a better wetting of the hair by the ready-to-use preparation.

As contemplated herein, anionic surfactants have the characterizing feature of a water-solubilizing anionic group such as a carboxylate, sulfate, sulfonate or phosphate group and a lipophilic alkyl group having approximately 8 to 30 C atoms. The molecule can additionally contain glycol or polyglycol ether groups, ester, ether and amide groups and hydroxyl groups. Examples of such anionic surfactants, in each case in the form of the sodium, potassium and ammonium and also the mono-, di- and trialkanolammonium salts having 2 to 4 C atoms in the alkanol group, are linear and branched fatty acids having 8 to 30 C atoms (soaps); ether carboxylic acids, in particular of the formula RO(CH₂CH₂O)_xCH₂COOH, in which R is a linear alkyl group having 8 to 30 C atoms and x=0 or 1 to 16; acyl sarcosides; acyl taurides; acyl isethionates; sulfosuccinic acid mono- and dialkyl esters and sulfosuccinic acid monoalkyl polyoxyethyl esters; linear alkane sulfonates; linear α-olefin sulfonates; sulfonates of unsaturated fatty acids; α-sulfofatty acid methyl esters of fatty acids; alkyl sulfates and alkyl ether sulfates, in particular of the formula RO(CH₂CH₂O)_xSO₃H, in which R denotes a linear alkyl group having 8 to 30 C atoms and x denotes 0 or a number from 1 to 12; mixtures of surface-active hydroxy sulfonates; sulfated hydroxyalkyl polyethylene and/or hydroxyalkylene propylene glycol ethers; esters of tartaric acid and citric acid with alcohols; alkyl and/or alkenyl ether phosphates of the formula RO(C₂H₄O)_xP(=O)(OH)(OR′), in which R denotes an aliphatic, optionally unsaturated hydrocarbon residue having 8 to 30 carbon atoms, R′ denotes hydrogen, a residue (CH₂CH₂O)_yR, and x and y independently of each other denote a number from 1 to 10; sulfated fatty acid alkylene glycol esters of the formula RC(O)O(alkO)_nSO₃H, in which R denotes a linear or branched, aliphatic, saturated and/or unsaturated alkyl residue having 6 to 22 C atoms, alk denotes CH₂CH₂, CH(CH₃)CH₂ and/or CH₂CH(CH₃) and n denotes a number from 0.5 to 5; and monoglyceride sulfates and monoglyceride ether sulfates. Suitable anionic surfactants are alkyl sulfates, alkyl ether sulfates and ether carboxylic acids.

The foil applicator according to an embodiment has the characterizing feature that the leaf-like substrate (A) is closely bonded to the nonwoven supporting material of the second layer (ii). To that end the nonwoven supporting material is fixed to the leaf-like substrate before or after loading with the bleaching preparation (B), by welding or gluing over the entire surface area or at certain points. Further polymers are optionally used to that end at the desired contact surfaces or contact points, which polymers are selected for example from polyacrylates, polyvinyl acetates, polybutadienes, latex and butadiene-styrene copolymers.

Therefore an embodiment herein is a foil applicator having the characterizing feature that the second layer is fixed to the leaf-like substrate by gluing and/or welding the supporting material. A further embodiment is therefore a foil applicator having the characterizing feature that the second layer is fixed to the leaf-like substrate by spot welding the supporting material.

The entire surface of the leaf-like substrate can be coated with the layer (ii) encompassing the bleaching preparation (B), or only certain areas of the substrate can be coated. In one embodiment, only the center of the leaf-like substrate can be coated with the bleaching preparation (B) embedded in the nonwoven supporting material, with for example an uncoated margin of around 0.2 to around 1.5 cm being left on the leaf-like substrate. This ensures that when the strand is wrapped, no bleaching preparation is exposed on the outside of the wrap, thus preventing an undesired lightening of adjacent hair sections.

The amount and film thickness of the preparation, in particular the substrate and preparation masses, are also matched to one another. Highlighting foils as contemplated herein are suitable in which the bleaching preparation (B) makes up at least about 10 wt. %, for example at least about 25 wt. %, such as at least about 50 wt. % of the total weight of the highlighting foil.

The loading of the nonwoven supporting material with the bleaching preparation (B) can be performed by various methods. The bleaching preparation (B) of the second layer is either scattered or pressed into the nonwoven supporting material as a powder or brushed, pressed or rubbed in as a paste or emulsion.

As the substantial constituent the bleaching preparation (B) contains a solid peroxodisulfate salt or two or more thereof to activate and intensify the lightening effect of the preparation.

An embodiment herein has the characterizing feature that the solid peroxodisulfate salt is selected from the group that is formed from ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate.

In an exemplary embodiment, it has furthermore proved suitable for the bleaching preparation (B) to contain at least two different peroxodisulfates. Suitable peroxodisulfate salts are combinations of ammonium peroxodisulfate and potassium peroxodisulfate and/or sodium peroxodisulfate.

The bleaching preparations (B) contain solid peroxodisulfate salts in an amount from about 0.1 to about 80 wt. %, for example from about 1 to about 60 wt. %, such as from about 2 to about 50 wt. %, relative in each case to the total weight of the bleaching preparation (B).

The bleaching agents contemplated herein can contain a further bleaching strength intensifier in addition to the solid peroxodisulfate salts.

Suitable bleaching strength intensifiers are inorganic peroxo compounds selected from ammonium peroxomonosulfate, alkali metal peroxomonosulfates, alkali metal peroxodiphosphates and alkaline-earth metal peroxides. Exemplary bleaching strength intensifiers are potassium hydrogen peroxomonosulfate, potassium peroxodiphosphate, magnesium peroxide and barium peroxide.

Compounds which under perhydrolysis conditions yield aliphatic peroxocarboxylic acids having suitably 1 to 10 C atoms, in particular 2 to 4 C atoms, and/or optionally substituted perbenzoic acid can likewise be used as bleach intensifiers. Polyacylated alkylene diamines, in particular tetraacetyl ethylene diamine (TAED), acylated triazine derivatives, in particular 1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine (DADHT), acylated glycolurils, in particular tetraacetyl glycoluril (TAGU), N-acylimides, in particular N-nonanoyl succinimide (NOSI), acylated phenol sulfonates, in particular n-nonanoyl- or isononanoyloxybenzenesulfonate (n- or i-NOBS), carboxylic anhydrides, in particular phthalic anhydride, acylated polyhydric alcohols, in particular triacetin, ethylene glycol diacetate and 2,5-diacetoxy-2,5-dihydrofuran, are exemplary.

Carbonate salts or hydrogen carbonate salts can be used herein as bleach intensifiers of the carbonic acid derivative type. These are selected, for example, from the group of ammonium, alkali metal (in particular Na and K) and alkaline-earth metal (in particular Mg and Ca) carbonate salts or hydrogen carbonate salts. Particularly suitable carbonate or hydrogen carbonate salts are ammonium hydrogen carbonate, ammonium carbonate, sodium hydrogen carbonate, sodium carbonate, potassium hydrogen carbonate, potassium carbonate, magnesium carbonate and calcium carbonate. These salts can be used as bleach intensifiers alone or in mixtures of at least two representatives thereof.

Furthermore, alkyl carbonates, alkyl carbamates, silyl carbonates and silyl carbamates are suitable bleach intensifiers for use herein.

Bleaching strength intensifiers for use herein can furthermore consist of nitrogen-containing, optionally cationic heterocyclic compounds. Imidazole can be cited in particular as an example of a nitrogen-containing heterocyclic bleaching strength intensifier. Particularly suitable nitrogen-containing, heterocyclic bleaching strength intensifiers are the quaternary cations of pyridines and 3,4-dihydroisoquinolines, such as salts of 4-acetyl-1-methylpyridinium, in particular 4-acetyl-1-methylpyridinium-p-toluenesulfonate, salts of 2-acetyl-1-methylpyridinium, in particular 2-acetyl-1-methylpyridinium-p-toluenesulfonate, and salts of N-methyl-3,4-dihydroisoquinolinium, in particular N-methyl-3,4-dihydroisoquinolinium-p-toluenesulfonate.

The bleaching strength intensifiers used in addition to the peroxodisulfate salts are included in the cosmetic bleaching preparation for example in amounts from about 0.5 to about 30 wt. %, for example in amounts from about 2 to about 20 wt. %, relative in each case to the total weight of the bleaching preparation (B).

To further increase the lightening capacity at least one optionally hydrated SiO₂ compound can additionally be added to the composition as a bleach intensifier. Although even small amounts of the optionally hydrated SiO₂ compounds increase the lightening capacity, the optionally hydrated SiO₂ compounds can be used in amounts from about 0.05 wt. % to about 15 wt. %, for example in amounts from about 0.15 wt. % to about 10 wt. %, such as in amounts from about 0.2 wt. % to about 5 wt. %, relative in each case to the bleaching preparation (B). The specified amounts indicate the content of SiO₂ compounds (excluding their water component) in the agents.

The exemplary embodiments are subject to no restrictions in principle regarding the optionally hydrated SiO₂ compounds. Silicas, oligomers and polymers thereof as well as salts thereof are suitable. Exemplary salts are alkaline-earth metal salts and alkali metal salts, in particular potassium and sodium salts. In an exemplary embodiment, sodium salts are used.

A further embodiment is therefore a foil applicator having the characterizing feature that the bleaching preparation (B) additionally contains at least silica, oligomers or polymers thereof, and/or one of the alkali or alkaline-earth metal salts thereof.

The optionally hydrated SiO₂ compounds can be present in various forms. According to an embodiment, the SiO₂ compounds are used in the form of silica gels or salts thereof, silicates, for example as water glass.

Likewise suitable are water glasses formed from a silicate of the formula (SiO₂)_n(Na₂O)_m(K₂O)_p, where n denotes a positive rational number and m and p independently of each other denote a positive rational number or 0, with the provisos that at least one of the parameters m or p is different from 0 and that the ratio of n to the sum of m and p is between 1:4 and 4:1.

In particular, metasilicates, which are characterized according to the formula above by a ratio of n to the sum of m and p of 1 and which can be regarded as chain-like polymeric structures of the anion [SiO₃]²⁻, can be used. Sodium metasilicate of the formula [NaSiO₃] is particularly suitable.

In addition to the components described by the empirical formula, the water glasses can also contain small amounts of further additives, such as phosphates or magnesium salts.

Water glasses that are suitable are sold inter alia under the names Ferrosil® 119, soda water glass 40/42, Portil® A, Portil® AW and Portil® W and Britesil® C20.

The bleaching preparation (B) can moreover additionally contain a polymer to improve the loading onto the supporting material and in particular to adjust the viscosity of the ready-to-use lightening agent. Polymers that can be used are non-ionic polymers, for example vinyl pyrrolidinone/vinyl acrylate copolymers, polyvinyl pyrrolidinone or vinyl pyrrolidinone/vinyl acetate copolymers, zwitterionic and amphoteric polymers, for example acrylamidopropyl trimethylammonium chloride/acrylate copolymers, anionic polymers such as for example polyacrylic acids or crosslinked polyacrylic acids, natural thickening agents or thickening agents derived from natural thickening agents, such as agar-agar, guar gum, alginic acid, xanthan gum, gum arabic, karaya gum, carob seed meal, linseed gums, dextrans, cellulose derivatives, starch fractions and derivatives, such as amylose, amylopectin and dextrins, or fully synthetic hydrocolloids, such as polyvinyl alcohol.

It has been found that water-soluble polymers can be used to particular advantage here. Such bleaching preparations are detached from the supporting material particularly well in the wrapped hair strands and can thus be distributed particularly well between the hair fibers. This leads to a uniform lightening result. Polymers that are particularly suitable for use herein are therefore cellulose, cellulose ethers such as methyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, polyelectrolytes such as alginic acid, xanthan gum, gum arabic, or modified, natural thickening agents such as reaction products of guar gum with chloroacetic acid, with ethylene oxide or with propylene oxide, or polyvinyl alcohol.

The decolorization of hair, in particular hair of a dark initial color, can lead to undesired color shifts. This is because the natural hair color is determined by melanins in the cortex of the hair fiber, the ratio between the two pigment classes, eumelanins with brownish-black tones and pheomelanins with reddish-orange tones, determining the actual hair color. In the bleaching process the natural melanin dyes are destroyed by oxidative action, resulting in a decolorization of the fibers. However, owing to the differing oxidative decomposition rates of the different melanin pigment classes, hair is not decolorized uniformly. In darker fibers with a high melanin content a certain proportion of dyes usually remains, which is frequently reflected in yellowish to reddish shades. Therefore the bleaching of darker hair in particular leads to a color shift towards warmer shades.

Such color shifts towards warmer shades are generally undesirable to the user. Therefore this color shift is usually counteracted by shading with the corresponding complementary color in accordance with color theory. The goal is for the bleaching result to give a silvery-cool impression. The person skilled in the art refers to matting in this context. Depending on the initial hair color, a customized mix of tinting agents is used in order to balance out more reddish color shifts with greenish tinting agents or more yellowish color shifts with somewhat violet tinting agents.

Suitable tinting agents are in particular substantive dyes, in particular ones that are sufficiently stable under the oxidative and highly alkaline conditions of bleaching.

In a further embodiment the bleaching preparation (B) therefore additionally contains a combination of a blue substantive dye and a red substantive dye, wherein the weight ratio between the sum of all blue substantive dyes and the sum of all red substantive dyes has a value greater than or equal to 1. In this way it is possible to avoid undesired color shifts towards pink or rose-colored shades.

Exemplary agents for use herein therefore have the characterizing feature that the total weight of all blue substantive dyes is greater than the total weight of all red substantive dyes. Exemplary agents therefore have the characterizing feature that the weight ratio between the sum of all blue substantive dyes and the sum of all red substantive dyes has a value from 1 to 100, for example from about 1.5 to about 10, such as from about 2 to about 4.

In principle there are no limits to the choice of substantive dyes. Substantive dyes are conventionally divided into anionic, cationic and non-ionic substantive dyes. Substantive dyes that can be used herein are nitrophenylene diamines, nitroaminophenols, azo dyes, anthraquinones or indophenols, if these substantive dyes have an adequate resistance to the harsh conditions of the bleaching process.

The bleaching preparation (B) in an embodiment contains as a blue substantive dye an anionic substantive dye, selected in particular from compounds with the name bromophenol blue or tetrabromophenol blue.

The bleaching preparation (B) in an embodiment contains as a red substantive dye an anionic substantive dye, for example from the group of fluorescein dyes. Suitable red substantive dyes are known under the names Acid Red 92, Acid Red 98, Acid Red 94, Acid Red 87 and Acid Red 51. Acid Red 92 (also D&C RED No. 28 or Phloxin B) is particularly suitable.

Dye combinations that are suitable for use for matting in the bleaching preparation (B) are those containing at least the combination of tetrabromophenol blue and Acid Red 92, tetrabromophenol blue and Acid Red 98, tetrabromophenol blue and Acid Red 94, tetrabromophenol blue and Acid Red 87 or tetrabromophenol blue and Acid Red 51.

To increase the stability of the bleaching preparation and to avoid a premature reaction to water, it is convenient for the bleaching preparation (B) embedded in the nonwoven supporting material to be anhydrous.

Anhydrous as used herein means that the bleaching preparation has a water content of less than about 5.0 wt. %, for example less than about 1.0 wt. %, for example less than about 0.1 wt. %, such as less than about 0.05 wt. %, relative in each case to the total weight of the bleaching preparation.

The anhydrous bleaching preparation (B) that is applied to the leaf-like substrate embedded in the nonwoven supporting material can be in a solid, semi-solid, liquid, disperse, emulsified, suspended or gel form. In one embodiment the bleaching preparation is in solid form.

The bleaching preparation can contain further auxiliary substances, active ingredients and additives. These include in particular, where chemically possible, waxes and oils that allow a dedusting of the preparation and optionally a simplified application on or embedding in the supporting material.

Suitable waxes and oils are in particular esters of mono- or polycarboxylic acids with a total carbon number from 18 to 57 carbon atoms and in particular mineral oils, such as paraffin oil.

It has furthermore proved advantageous for the bleaching agent preparations to contain a stabilizer or complexing agent. Exemplary stabilizers are phenacetin, alkali benzoates (sodium benzoate) and salicylic acid.

Also suitable is the use of complexing agents. Complexing agents are substances that are capable of complexing metal ions. Exemplary complexing agents are chelating agents, which form bonds with a metal ion via multiple coordination sites.

All complexing agents of the prior art can be used in the context herein. Exemplary complexing agents are nitrogen-containing polycarboxylic acids, in particular EDTA, and phosphonates, suitably hydroxyalkane or aminoalkane phosphonates, such as 1-hydroxyethane-1,1-diphosphonate (HEDP) or the disodium or tetrasodium salt thereof and/or ethylenediamine tetramethylene phosphonate (EDTMP) or the hexasodium salt thereof and/or diethylenetriamine pentamethylene phosphonate (DTPMP) or the heptasodium or octasodium salt thereof.

Lightening agents for keratinic fibers have the characterizing feature of having an alkaline pH. A further embodiment consists in that the ready-to-use agent has a pH in the range of from about 7.0 to about 12.0, for example from about 8.0 to about 11.0. The pH values contemplated herein are pH values measured at a temperature of about 22° C. Acidifying and alkalizing agents commonly used in cosmetics are familiar to the person skilled in the art for adjusting the pH. The alkalizing agents that can be used for adjusting the pH are typically chosen from inorganic salts, in particular alkali and alkaline-earth metals, organic alkalizing agents, in particular amines, basic amino acids and alkanol amines, and ammonia. Exemplary acidifying agents are food acids, such as for example citric acid, acetic acid, malic acid or tartaric acid, as well as dilute mineral acids.

It has however been found that in one embodiment bleaching preparations (B) that are suitable for use herein have the characterizing feature that they additionally contain an inorganic, solid alkalizing agent. This alkalizing agent at least partially dissolves on contact with water on the hair strand and thus establishes the alkaline pH required for bleaching processes. The inorganic alkalizing agent for example is selected from the group formed from sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, sodium phosphate, potassium phosphate, sodium silicate, potassium silicate, sodium carbonate and potassium carbonate. The compositions for example contain the alkalizing agents in amounts from about 0.2 to about 25 wt. %, such as from about 0.5 to about 10 wt. %.

To ensure that the foil applicator is easy to handle and that the bleaching preparation is rapidly released or dissolved, in an embodiment the second layer containing the bleaching preparation (B) is not embedded in the nonwoven supporting material too great a thickness. Suitable film thicknesses are for example from about 5 to about 200 μm.

An embodiment therefore has the characterizing feature that the cosmetic bleaching preparation (B) has a film thickness from about 5 μm to about 200 μm, for example from about 10 μm to about 150 μm, for example from about 15 μm to about 120 μm, such as from about 20 μm to about 100 μm.

After mixing the bleaching preparation (B) with an aqueous oxidizing agent preparation (OX), the ready-to-use lightening agents are applied by being brought into contact with the strand to be treated. The aqueous oxidizing agent preparation (OX) in an embodiment contains hydrogen peroxide as the oxidizing agent.

To that end an aqueous oxidizing agent preparation (OX) is added to the bleaching preparation of the foil applicator either immediately before the hair strand to be lightened is separated or after separation, along with the hair strand to be lightened. This is done either by spraying using conventional spray bottles or by spreading with the aid of an applicator or brush. Through the penetration of water into the water-permeable supporting material of the second applicator layer the bleaching preparation (B) is dissolved and together with the oxidizing agent preparation (OX) forms the ready-to-use lightening agent. The strand to be treated is then wrapped in the applicator foil, wherein the outside of the wrap is formed completely from the leaf-like substrate so that adjacent hair sections do not come into contact with the bleaching preparation. After the desired contact period the foil applicator is removed and the treated hair section is rinsed thoroughly.

The oxidizing agent preparation (OX) contains at least hydrogen peroxide as the oxidizing agent in a cosmetic carrier. Hydrogen peroxide itself is in an embodiment used as an aqueous solution. Hydrogen peroxide can however also be used in the form of a solid addition compound of hydrogen peroxide with inorganic or organic compounds, such as sodium percarbamide, polyvinyl pyrrolidinone n H₂O₂ (n is a positive integer greater than 0), urea peroxide and melamine peroxide.

Hydrogen peroxide is for example contained in the ready-to-use agent in an amount from about 0.1 to about 25 wt. %, for example from about 1 to about 20 wt. %, such as from about 4.5 to about 9 wt. %, calculated in each case against 100% hydrogen peroxide and relative to the total weight of the ready-to-use agent.

The cosmetic carrier of the oxidizing agent preparation (OX) is aqueous, alcoholic or aqueous-alcoholic. For the purposes of hair bleaching such carriers are for example creams, emulsions, gels or surfactant-containing foaming solutions, such as for example shampoos, foam aerosols or other preparations which are suitable for use on the hair. An aqueous carrier contains at least about 40 wt. %, for example at least about 50 wt. %, of water. As contemplated herein, aqueous-alcoholic carriers are understood to be hydrous compositions containing about 3 to about 70 wt. % of a C₁ to C₄ alcohol, in particular ethanol or isopropanol. The agents herein can additionally contain further organic solvents.

In another embodiment, one or more of the complexing agents described above in the oxidizing agent preparation (OX) are used to stabilize the hydrogen peroxide.

Oxidizing agent preparations contemplated herein are for examle aqueous, free-flowing preparations. The agents can contain surface-active substances selected from anionic and non-ionic, zwitterionic, amphoteric and cationic surfactants.

Non-ionic surfactants and emulsifiers contain as a hydrophilic group a polyol group, a polyalkylene glycol ether group or a combination of a polyol and polyglycol ether group, for example. Suitable compounds are in particular addition products of 1 to 50 mol of ethylene oxide and/or 0 to 5 mol of propylene oxide with linear and branched fatty alcohols having 8 to 30 C atoms, with fatty acids having 8 to 30 C atoms and with alkyl phenols having 8 to 15 C atoms in the alkyl group and alkyl polyglycosides corresponding to the general formula RO—(Z), in which R denotes alkyl, Z sugar and x the number of sugar units.

Examples of zwitterionic surfactants are betaines. A suitable zwitterionic surfactant is the fatty acid amide derivative known under the INCI name Cocamidopropyl Betaine. Amphoteric surfactants that are suitable for use herein are N-alkyl glycines, N-alkyl propionic acids, N-alkyl aminobutyric acids, N-alkyl iminodipropionic acids, N-hydroxyethyl-N-alkyl amidopropyl glycines, N-alkyl taurines, N-alkyl sarcosines, 2-alkyl aminopropionic acids and alkyl aminoacetic acids. Amphoteric surfactants by way of example are N-cocoalkyl aminopropionate, cocoacylaminoethyl aminopropionate and C₁₂-C₁₈ acyl sarcosine. Cationic surfactants of the quaternary ammonium compound, esterquat and amidoamine type are suitable for use in ready-to-use agents. Exemplary quaternary ammonium compounds are ammonium halides, such as alkyltrimethylammonium chlorides, dialkyldimethylammonium chlorides and trialkylmethylammonium chlorides, as well as the imidazolium compounds known under the INCI names Quaternium-27 and Quaternium-83.

In an embodiment anionic, non-ionic, zwitterionic and/or amphoteric surfactants and mixtures thereof can be used.

The oxidizing agent preparation (OX) can contain further active ingredients, auxiliary substances and additives. Further active ingredients, auxiliary substances and additives that can be used are for example anionic polymers (such as carbomers, copolymers and cross-polymers of acrylic acid, methacrylic acid, maleic acid, itaconic acid and optionally further non-ionic monomers); non-ionic polymers (such as vinyl pyrrolidinone/vinyl acrylate copolymers, polyvinyl pyrrolidinone and vinyl pyrrolidinone/vinyl acetate copolymers and polysiloxanes); zwitterionic and amphoteric polymers (such as acrylamidopropyl trimethylammonium chloride/acrylate copolymers and octylacrylamide/methyl methacrylate/tert-butylaminoethyl methacrylate/2-hydroxypropyl methacrylate copolymers); thickening agents (such as agar-agar, guar gum, alginates, xanthan gum, gum arabic, karaya gum, carob seed meal, linseed gums, dextrans, cellulose derivatives, e.g. methyl cellulose, hydroxyalkyl cellulose and carboxymethyl cellulose, starch fractions and derivatives such as amylose, amylopectin and dextrins, clays such as bentonite or fully synthetic hydrocolloids such as for example polyvinyl alcohol); texturizing agents (such as sugars, maleic acid and lactic acid) and consistency modifiers (such as sugar esters, polyol esters or polyol alkyl ethers); protein hydrolysates (in particular elastin, collagen, keratin, milk protein, soy protein and wheat protein hydrolysates, condensation products thereof with fatty acids); perfume oils; conditioning oils; cyclodextrins; defoaming agents such as silicones; dyes and pigments to color the agent; light stabilizers (in particular derivatized benzophenones, cinnamic acid derivatives and triazines); further fats and waxes (such as fatty alcohols, beeswax, montan wax and paraffins); swelling and penetrating substances (such as glycerol, propylene glycol monoethyl ethers, 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); propellants (such as propane-butane mixtures, N₂O, dimethyl ether, CO₂ and air) and antioxidants.

The person skilled in the art will select these further substances in accordance with the desired properties of the agents. With regard to further optional components and to the amounts of these components used, reference is expressly made to the relevant manuals known to the person skilled in the art, for example Kh. Schrader, Grundlagen and Rezepturen der Kosmetika, 2^nd Edition, Hüthig Buch Verlag, Heidelberg, 1989.

In addition to the possibility of applying hydrogen peroxide to the foil applicator via the oxidizing agent preparation (OX) and thus providing the ready-to-use lightening agent with the bleaching preparation (B), there is also the possibility of placing hydrogen peroxide in solid form on the foil applicator and generating the ready-to-use lightening agent by bringing it into contact with water or an aqueous preparation. Hydrogen peroxide in solid form is understood herein to mean addition products of hydrogen peroxide with solid compounds.

Hydrogen peroxide can form addition products with many inorganic and organic compounds. They include addition products with urea (ureα-hydrogen peroxide addition compound, UHP, hydroperite, perhydrol urea, hydrogen peroxide-carbamide, percarbamide), melamine (melamine peroxide) and polyvinyl pyrrolidinone (PVP-n H₂O₂) as well as percarbonates, in particular sodium percarbonate and magnesium percarbonate, and perborates, in particular sodium perborate.

It has been found that for stability reasons it is convenient to physically separate the bleaching preparation (B) from the hydrogen peroxide addition products to begin with, as even slight traces of moisture can lead to instabilities and undesired decompositions. Therefore, in an embodiment, the foil applicator is covered with a further layer encompassing a solid oxidizing agent preparation (OX1). To separate the bleaching preparation (B) it is particularly advantageous to incorporate an additional interlayer between the oxidizing agent preparation (OX1) and the bleaching preparation (B) that allows a physical separation of the two preparations and thus prevents direct contact between the solid preparations. On the other hand it is suitable for the interlayer to be water-permeable so that the ready-to-use lightening agent is formed following the addition of water or an aqueous preparation comprising the bleaching preparation (B) and the solid oxidizing agent preparation (OX1).

A further embodiment herein is therefore a foil applicator in the form of a multilayer applicator that has the characterizing feature that the applicator additionally contains

• • (iii) a water-permeable barrier layer applied to layer (ii) and
  • (iv) a solid oxidizing agent preparation (OX1) containing as oxidizing agent a solid addition product of hydrogen peroxide with organic or inorganic compounds, applied to the barrier layer (iii).

The solid oxidizing agent preparation (OX1) of layer (iv) contains a solid addition product of hydrogen peroxide with organic or inorganic compounds. Hydrogen peroxide can form addition products with many inorganic and organic compounds. They include addition products with urea (ureα-hydrogen peroxide addition compound, UHP, hydroperite, perhydrol urea, hydrogen peroxide-carbamide, percarbamide), melamine (melamine peroxide) and polyvinyl pyrrolidinone (PVP-n H₂O₂) as well as percarbonates, in particular sodium percarbonate and magnesium percarbonate, and perborates, in particular sodium perborate.

In an embodiment the oxidizing agent preparation (OX1) contains a solid addition product of hydrogen peroxide with organic or inorganic compounds, which is selected from addition products with urea, melamine and polyvinyl pyrrolidinone.

The oxidizing agent preparation (OX1) contains the solid addition product of hydrogen peroxide with organic or inorganic compounds in an amount from about 0.1 to about 60 wt. %, for example from about 1 to about 50 wt. %, such as from about 2 to about 30 wt. %, calculated in each case as 100% H₂O₂ and relative to the total weight of the solid oxidizing agent preparation (OX1).

In an embodiment the solid oxidizing agent preparation (OX1) is also embedded in a nonwoven supporting material. In principle the nonwoven supporting materials used can be the same as the nonwoven supporting materials of the second layer (ii) described above. Supporting materials that are inert in respect of the oxidative environment of the ready-to-use lightening preparation are likewise suitable here. Nonwoven supporting materials made from polypropylene are suitable in particular.

The supporting materials are likewise given a hydrophilic finish to encourage the penetration and storage of water in this layer (iv). This accelerates the dissolution of the solid oxidizing agents, simplifies thorough mixing and thus shortens the contact period and improves wetting of the hair to be treated.

In addition to the oxidizing agent itself, the solid oxidizing agent preparation (OX1) can also contain further constituents, such as solid constituents. Such further active ingredients, auxiliary substances and additives that can be used herein are the substances described above, such as for example further interfacially active compounds, complexing agents, anionic, cationic or non-ionic, natural or synthetic thickening agents, texturizing agents and consistency modifiers, conditioning substances such as protein hydrolysates, conditioning oils; further fats and waxes; swelling and penetrating substances; opacifiers and pearlescent agents.

Layer (iv) encompassing the oxidizing agent preparation (OX1) for example has the same dimensions in terms of length and width as layer (ii). In order to adjust the proportions of each preparation to one another, it is suitable to achieve this adjustment through different film thicknesses.

An embodiment herein has the characterizing feature that the solid oxidizing agent preparation (OX1) of layer (iv) has a film thickness from about 5 μm to about 200 μm, for example from about 10 μm to about 150 μm, for example from about 15 μm to about 120 μm, such as from about 20 μm to about 100 μm.

To separate the bleaching preparation (B) and the solid oxidizing agent preparation (OX1) the foil applicator advantageously contains an interlayer or barrier layer (iii). This barrier layer is sandwiched between layers (ii) and (iv). It has at least the surface dimensions of layer (ii).

Layers (ii), (iii) and (iv) for example each have the same length and width and lie on top of one another with no lateral overlapping.

The interlayer (iii) is water-permeable, so when layer (iv) is wetted and the bleaching preparation is dissolved, a penetration of water into the bleaching preparation of layer (ii) is allowed. At the same time the interlayer should prevent a premature reaction between the constituents of layers (ii) and (iv) by direct contact, in particular in the presence of atmospheric moisture.

To this end the interlayer can have a lattice-like or woven structure or alternatively a nonwoven structure, with in each case suitable pores or openings that allow the passage of water and aqueous preparations. The water permeability can be influenced by the weave, the yarn density and/or the weight per unit area. Suitable materials for the interlayer are inter alia cellulose, viscose, pulp, polyethylene, polyethylene terephthalate, polypropylene, polyester, polylactate and mixtures thereof. Preferred materials for such an interlayer (iii) are polypropylene.

A further embodiment of a water-permeable interlayer (iii) consists of producing the interlayer (iii) from a water-soluble compound. Polymers that are swellable, erodible and/or soluble in water are suitable in particular. The term “soluble in water” should be understood to mean that a complete hydration takes place and a solution forms. The term “swellable in water” should be understood to mean that on contact with water, water molecules penetrate into the layer, leading to changes in volume and shape and possibly forming a gel. The term “erodible in water” means that the interlayer disintegrates on contact with water. This results in smaller fragments, which can be further eroded with water or washed away. Complete solubility in water is not necessary for erodibility, however. In this embodiment the interlayer (iii) is in film form. Exemplary materials for the interlayer (iii) are cellulose, inulins, cellulose derivatives, in particular hydroxyalkyl celluloses and carboxyalkyl celluloses, and polyvinyl alcohols and polyvinyl acetate-polyvinyl alcohol copolymers.

An embodiment herein has the characterizing feature that the water-permeable interlayer (iii) has a film thickness from about 0.1 μm to about 100 μm, for example from about 0.5 μm to about 50 μm, such as from about 1 μm to about 50 μm.

The interlayer (iii) and the oxidizing agent preparation layer (iv) are closely bonded to the bleaching preparation layer (ii), for example by gluing and/or welding, such as by spot welding.

To prevent premature reactions of the exposed layer of the foil applicator with moisture, in particular atmospheric moisture, during storage, it is advantageous to cover this layer with a water-impermeable foil.

A further embodiment is therefore a foil applicator of the first subject-matter, which has the characterizing feature that the applicator encompasses as an additional layer (v) a peelable, water-impermeable foil by means of which the uncovered surface of the bleaching preparation layer (ii) or of the oxidizing agent preparation layer (iv) that is exposed to the air is completely covered.

In another embodiment layer (v) as the peelable foil has the same surface dimensions as the leaf-like substrate of layer (i). The water-impermeable foil of layer (v) is bonded to the uncoated margin of the leaf-like substrate by welding. The welded bond should be structured such that the foil of layer (v) can be manually peeled away from layer (i) without great effort and without detaching the further active ingredient layer or layers. This can be achieved by means of the surface finish of the layers and by welding and is known to the person skilled in the art.

Polyethylene, polypropylene and polyethylene terephthalate as well as polylactide (polylactic acid) are suitable in particular as water-impermeable foil materials for layer (v).

The foil (v) for example has a film thickness from about 0.01 μm to about 20 μm, such as from about 0.05 μm to about 5 μm.

The water-impermeable foil is peeled off manually immediately before use, thus exposing the reactive bleaching preparation and/or oxidizing agent preparation of the foil applicator.

The foil applicators are used for the selective lightening and bleaching of keratinic fibers.

Another embodiment also provides a method for lightening keratinic fibers, which has the characterizing feature that a foil applicator consisting of at least two layers encompassing

• • (i) a leaf-like substrate as the first layer and
  • (ii) a bleaching preparation (B) containing a solid peroxodisulfate salt and embedded in a nonwoven supporting material applied to the leaf-like substrate as the second layer,
    is treated on the side of the bleaching preparation with an oxidizing agent preparation (OX) containing in a cosmetic carrier at least hydrogen peroxide,
    immediately after which at least one bundle of keratinic fibers is laid on the foil applicator prepared in this way and wrapped in the foil applicator,
    left in the foil applicator for a contact period of about 10 to about 60 minutes, then the foil is removed and the bundle of keratinic fibers is rinsed.

The bundle of keratin-containing fibers to be treated is for example a bundle or strand of human hair that has been selected and separated from the remaining head hair. Prior to treatment the bundle of keratin-containing fibers to be treated is separated from the other fibers using a comb or another suitable aid.

Depending on the size of the foil applicator, two or more bundles of hair can also be wrapped, wound or packed simultaneously into a foil applicator. Certain sections of the hair bundle only, such as the tips, partial lengths, or the entire hair fiber lengths up to where they join the scalp can be wrapped.

If the foil applicator encompasses a protective layer in the form of a peelable, water-impermeable layer (v), this is removed immediately before use. The wrapping, winding or packing of the fiber bundle takes place in such a way that the leaf-like substrate (A) of layer (i) forms the outside of the pack, while the bleaching preparation (B) of layer (ii) can come into contact with the selected fiber bundle.

The treatment with the oxidizing preparation (OX) takes place immediately before the fiber bundle is packed into the applicator. Depending on the viscosity, the oxidizing agent preparation can be applied with a brush, with a spray bottle or using an aerosol can in the form of an aerosol or fine mist, directly onto the foil applicator prior to wrapping or onto the selected fiber bundle with the not yet wrapped foil applicator underneath it.

Depending on the needs and wishes of the user, individual or multiple different strands distributed throughout the hair can be wrapped in this way. Localized, cumulated or evenly distributed reflexes and highlights can be produced on the hair in this way. Preferably, multiple strands of head hair are wrapped in foil applicators to achieve uniform lightening results.

The contact period is about 10 to about 60 minutes, for example about 30 to about 45 minutes. The contact phase can take place at room temperature or at elevated temperatures from about 40 to about 45° C. The application temperature is however suitably room temperature. Depending on the contact period and temperature, different intensities of lightening results can be obtained, with higher temperatures and/or longer contact periods leading to a more intense lightening.

At the end of the contact period the foil applicators are removed, the treated fiber bundles are rinsed with water and optionally treated with commercial shampoos and conditioners.

All that has been stated in respect of the foil applicators herein applies with necessary alterations to further embodiments of the methods herein.

In the case of multilayer foil applicators encompassing a solid oxidizing agent preparation (OX1) in addition to the bleaching preparation (B), activation with water alone is sufficient. Thirdly provided is a method for lightening keratinic fibers, which has the characterizing feature that a multilayer foil applicator encompassing

• • (i) a leaf-like substrate as the first layer and
  • (ii) a bleaching preparation containing a solid peroxodisulfate salt and embedded in a nonwoven supporting material applied to the leaf-like substrate as the second layer,
  • (iii) a water-permeable barrier layer applied to layer (ii) and
  • (iv) a solid oxidizing agent preparation (OX1) containing as oxidizing agent a solid addition product of hydrogen peroxide with organic or inorganic compounds, applied to the barrier layer (iii),
    is treated with water on the side of the oxidizing agent preparation (OX1),
    immediately after which at least one bundle of keratinic fibers is laid on the foil applicator prepared in this way and wrapped in the foil applicator,
    left in the foil applicator for a contact period of about 10 to about 60 minutes, then the foil is removed and the bundle of keratinic fibers is rinsed.

The bleaching preparation and the oxidizing agent preparation on the foil are wetted with water immediately before application in order to be used.

In an alternative application form one or more of the foil applicators loaded with bleaching preparation and oxidizing agent preparation can be wrapped around a wet bundle of keratinic fibers such as for example a wet strand of human hair. It makes no difference whether the hair strand is separated from the wet hair and is still sufficiently wetted or whether the hair strand is isolated from the dry hair and wetted immediately before being wrapped in the foil applicator. For lightening longer hair in particular, however, it makes sense to isolate a bundle of keratinic fibers or a strand from the dry hair, to wet this bundle or strand thoroughly, and to wrap this bundle wetted in this way in the foil applicator for lightening. A spray bottle is suitable in particular for wetting the strand.

All that has been stated in respect of the preceding subject-matters herein applies with necessary alterations to further preferred embodiments of the method herein.

The use of these foil applicators in combination or in close succession with further color-changing and shape-changing agents, such as for example oxidative lightening and/or coloring agents, is likewise possible and can be used correspondingly by the person skilled in the art or the user according to his needs and wishes. Natural, attractive color reflexes and highlights can be obtained in this way in particular in uniformly colored hair or in a naturally very homogeneous hair color. Alternatively, strong contrasts and accents are possible within the hair style with more intense lightening.

While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.

Claims

1. A foil applicator for selective lightening of keratinic fibers, the foil applicator comprising: wherein the bleaching preparation is embedded in a nonwoven supporting material.

a first layer comprising a leaf-like substrate; and

a second layer comprising a bleaching preparation containing a solid peroxodisulfate salt applied to the leaf-like substrate,

2. The foil applicator according to claim 1, wherein the leaf-like substrate is an aluminum foil.

3. The foil applicator according to one of claim 1, wherein the second layer is attached by gluing and/or welding the nonwoven supporting material to the leaf-like substrate.

4. The foil applicator according to claim 1, wherein the solid peroxodisulfate salt is chosen from ammonium peroxodisulfate, potassium peroxodisulfate and sodium peroxodisulfate.

5. The foil applicator according to claim 1, wherein the bleaching preparation additionally contains silica, oligomers or polymers thereof, and/or one of alkali or alkaline-earth metal salts thereof.

6. The foil applicator according to claim 1, wherein the bleaching preparation has a film thickness of from about 5 μm to about 200 μm.

7. The foil applicator according to claim 6, wherein the bleaching preparation has the film thickness of from about 10 μm to about 150 μm.

8. The foil applicator according to claim 7, wherein the bleaching preparation has the film thickness of from about 20 μm to about 100 μm.

9. The foil applicator according to claim 1, wherein the foil applicator additionally comprises:

a water-permeable barrier layer applied to the second layer; and

a solid oxidizing agent preparation containing as an oxidizing agent a solid addition product of hydrogen peroxide with organic or inorganic compounds, wherein the solid oxidizing agent preparation is applied to the water-permeable barrier layer.

10. The foil applicator according to claim 9, wherein the foil applicator comprises as an additional layer a peelable, water-impermeable foil by means of which an uncovered surface of the bleaching preparation or of the solid oxidizing agent preparation that is exposed to air is completely covered.

11. A method for lightening keratinic fibers, wherein the method comprises the steps of:

providing a foil applicator having a leaf-like substrate and a bleaching preparation containing a solid peroxodisulfate salt applied to the leaf-like substrate, wherein the bleaching preparation is embedded in a nonwoven supporting material;

treating the foil applicator with an oxidizing agent preparation containing hydrogen peroxide in a cosmetic carrier;

immediately thereafter, laying a bundle of keratinic fibers on the foil applicator and wrapping the bundle in the foil applicator;

leaving the bundle of keratinic fibers in the foil applicator for a contact period of about 10 to about 60 minutes;

removing the foil applicator; and

rinsing the bundle of keratinic fibers.

12. A method for lightening keratinic fibers, wherein the method comprises the steps of:

providing a multilayer foil applicator having; a first layer comprising a leaf-like substrate; a second layer comprising a bleaching preparation containing a solid peroxodisulfate salt applied to the leaf-like substrate, wherein the bleaching preparation is embedded in a nonwoven supporting material; a water-permeable barrier layer applied to the second layer; and a solid oxidizing agent preparation containing as an oxidizing agent a solid addition product of hydrogen peroxide with organic or inorganic compounds, wherein the solid oxidizing agent preparation is applied to the water-permeable barrier layer;

treating the multilayer foil applicator with water on a side with the solid oxidizing agent preparation;

immediately thereafter, laying a bundle of keratinic fibers on the multilayer foil applicator and wrapping the bundle in the multilayer foil applicator;

leaving the bundle of keratinic fibers in the multilayer foil applicator for a contact period of about 10 to about 60 minutes;

removing the multilayer foil applicator from the bundle of keratinic fibers; and

rinsing the bundle of keratinic fibers.