WO2000032729A1

WO2000032729A1 - Peroxide-containing preparations with stabilized optical brightening agents

Info

Publication number: WO2000032729A1
Application number: PCT/EP1999/008919
Authority: WO
Inventors: Miguel Osset Hernandez; Lidia Jimenez Carrillo; Mercedes Mendoza Cruz
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 1998-12-01
Filing date: 1999-11-20
Publication date: 2000-06-08
Also published as: DE19855346A1; CA2292107A1; AU3034200A

Abstract

The invention relates to peroxide-containing preparations with a content of optical brightening agents. The inventive preparations are characterized in that the optical brightening agents are present in the preparation in microencapsulated form.

Description

Preparations containing peroxide with stabilized optical brighteners

Field of the Invention

The invention is in the field of bleaching and disinfecting agents and relates to peroxide-containing preparations which contain optical brighteners in a microencapsulation.

State of the art

In the Mediterranean countries, but also in the United States, cold washing of textiles continues to dominate. As a result, conventional bleaching agents such as e.g. Perborates or percarbonates are rarely used because they do not show any particular activity at temperatures around 20 ° C. Liquid wash bleaches, which are, for example, surfactant preparations with a content of up to 10% by weight of hydrogen peroxide, are therefore usually added to the wash liquor.

In order to counteract yellowing of the laundry, optical brighteners are added to the bleaching agents, which brighten up the fibers and then convert invisible UV radiation into visible, longer-wave light. The ultraviolet light absorbed from the sunlight is emitted again as a slightly bluish fluorescence, i.e. in the complementary color of the yellowing. Optical brighteners are usually dyes that are easily oxidized in a peroxide-containing environment and then lose their properties. Bleaching liquors containing these white toners are therefore only of limited shelf life in terms of the performance of this component. The object of the invention was to provide the simplest possible technical solution to the problem described. Description of the invention

The invention relates to peroxide-containing preparations containing optical brighteners, which are characterized in that the optical brighteners are in microencapsulated form.

Surprisingly, it was found that peroxide-containing textile bleaching agents can then be stably formulated with optical brighteners when used in microencapsulated form. The microcapsules are chemically and physically, in particular spatially, stable in the liquid compositions according to the invention, i.e. on average neither decomposition nor settling of the microcapsules occurs. In this way, peroxide-containing preparations can be produced with a practically free choice of optical brighteners.

Peroxide compounds

The term peroxide compounds is to be understood as meaning substances which contain an O-O group. Typical examples are perborates, percarbonates, percarboxylic acids and especially hydrogen peroxide. The aqueous compositions according to the invention preferably contain hydrogen peroxide in amounts of 1 to 10, preferably 5 to 8 and in particular 6 to 7% by weight. The calculation relates to 100% active substance, for example in the form of a 35% by weight aqueous solution.

Microcapsules

The term “microcapsule” is understood to mean aggregates which contain at least one solid or liquid core which is enclosed by at least one continuous shell, in particular a shell made of polymer (s). Usually, these are finely dispersed liquid or solid phases coated with film-forming polymers, in the production of which the polymers are deposited on the material to be encapsulated after emulsification and coacervation or interfacial polymerization. The microscopic capsules, also called nanocapsules, can be dried like powder. In addition to mononuclear microcapsules, multinuclear aggregates, also called microspheres, are known which contain two or more nuclei distributed in the continuous shell material. Single or multi-core microcapsules can also be enclosed by an additional second, third, etc. shell. Mononuclear microcapsules with a continuous shell are preferred. The cover can be made from natural, semi-synthetic or synthetic mate- rialien exist. Of course, wrapping materials are, for example, gum arabic, agar agar, agarose, maltodextrins, alginic acid or its salts, for example sodium or calcium alginate, fats and fatty acids, cetyl alcohol, collagen, chitosan, lecithins, gelatin, albumin, shellac, polysaccharides, such as starch or dextran, sucrose and waxes. Semi-synthetic casing materials include chemically modified celluloses, in particular cellulose esters and ethers, for example cellulose acetate, ethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose and carboxymethyl cellulose, and starch derivatives, in particular starch ethers and esters. Synthetic covering materials are, for example, polymers such as polyacrylates, polyamides, polyvinyl alcohol or polyvinyl pyrrolidone.

The microcapsules can have any shape in the production-related framework, but they are preferably approximately spherical. Their diameter along their greatest spatial extent can be between 10 nm (not visually recognizable as a capsule) and 10 mm, depending on the optical brighteners contained in them and the application. Visible microcapsules with a diameter in the range from 0.1 mm to 7 mm, in particular from 0.4 mm to 5 mm, are preferred. Microcapsules that can no longer be seen with the naked eye preferably have a diameter in the range from 20 to 500 nm, preferably 50 to 200 nm. The microcapsules can be obtained by methods known in the prior art, with coacervation and interfacial polymerization being of the greatest importance. All surfactant-stable microcapsules available on the market can be used as microcapsules, for example the commercial products (the shell material is given in brackets) Hallcrest microcapsules (gelatin, gum arabic), Coletica Thalaspheres (maritime collagen), Lipotec millicapsules (alginic acid, Agar-agar), Induchem Unispheres (lactose, microcrystalline cellulose, hydroxypropylmethyl cellulose); Unicerin C30 (lactose, microcrystalline cellulose, hydroxypropylmethyl cellulose), Kobo Glycospheres (modified starch, fatty acid esters, phospholipids), Softspheres (modified agar agar) and Kuhs Probiol Nanospheres (phospholipids).

The active ingredients are usually released from the microcapsules during use of the preparations containing them by destroying the shell as a result of mechanical, thermal, chemical or enzymatic action. In the bleaching agents which are usually used undiluted, the release is preferably carried out by mechanical action, in particular by mechanical forces, to which the microcapsules are exposed in the washing machine during metering, pumping or spinning. In a preferred embodiment of the invention, the compositions contain identical or different microcapsules in amounts of 0.1 to 10% by weight, in particular 0.2 to 8% by weight, extremely preferably 0.5 to 6% by weight. Optical brighteners

The optical brighteners which are used in microencapsulated form for the purposes of the invention are preferably those which are otherwise not stable in preparations containing peroxide. Typical examples of suitable optical brighteners are derivatives of diaminostilbenedisulfonic acid or its alkali metal salts. For example, derivatives of 4,4'-diamino-2,2'-stilbenedisulfonic acid (flavonic acid) are suitable, such as, in particular, the salts of 4,4'-bis (2-anilino-4-mo holino-1,3,5-triazinyl -6-amino) stilbene-2,2'-disulfonic acid or compounds of the same structure, which carry a diethanolamino group, a methylamino group, an anilino group or a 2-methoxyethylamino group instead of the morpholino group. Further may be present on the type of the substituted diphenyl brighteners, for example alkali metal salts of 4,4'-bis (2-sulfostyryl), ^4,4-bis (4-chloro-3-sulfostyryl) or 4- (4-chlorostyryl) -4 '- (2-sulfostyryl) diphenyls, methylumbelliferone, coumarin, dihydroquinolinone, 1, 3-diarylpyrazoline, naphthalic acid amide, benzoxazole, benzisoxalzole and benzimidazole linked via CH = CH bonds Systems, pyrene derivatives substituted by heterocycles and the like. Mixtures of the aforementioned brighteners can also be used. The potassium salt of 4,4'-bis (1,2,3-triazolyl) - (2-) - stilbin-2,2-sulfonic acid, which is sold under the brand name Phorwite® BHC 766, is preferred. As a rule, the microcapsules contain the optical brighteners in amounts of 1 to 75, preferably 10 to 60 and in particular 25 to 50 wt. It is also advantageous if the microcapsules also contain small amounts of a blue dye in addition to the usual brighteners in customary amounts, for example between 1 and 5% by weight, preferably between 2 and 3% by weight. Particularly preferred brighteners or dyes are naphthotriazolstilbenesulfonic acid, for example in the form of its sodium salt (Tinopal® RBS 200), and tetrabenzo-tetraazaporphin (Tinolux® BBS), distyrylbiphenylbis (triazinylamino) stilbene disulfonic acid (Tinopal® CDS-X), and in particular 4,4'-bis (2-sulfostyrene) biphenyl-di-sodium salt (Tinopal® CBS-X, commercial products from Ciba).

Sequestering agent

If the preparations are used to treat textiles, it is advisable to add electrolytes that serve as sequestering agents for heavy metal ions and thus counteract yellowing of the laundry. For this purpose, for example, silicates, phosphonic acids or phosphonates, polyacrylic acid compounds, alkali carbonates, lignin sulfonates and mixtures of the electrolytes mentioned are suitable. A particularly preferred sequestering agent is the methylglycinediacetic acid tri-sodium salt, which is sold as Trilon® M by BASF. The The total amount of the sequestering agents used is usually 0.1 to 2, preferably 0.3 to 1.5, and in particular 0.5 to 1.0,% by weight, based on the agent.

For the purposes of the invention, silicates are understood to mean salts and esters of orthosilicic acid Si (OH) and their self-condensation cycles. Accordingly, the following crystalline substances can be used as silicates:

(a) Neosilicates (island silicates) such as phenakite, olivine and zircon;

(b) Sorosilicates (group silicates) such as thortveitite and hemimorphite;

(c) cyclosilicates (ring silicates) such as, for example, benitoid, axinite, beryl, milarite, osumiiith or eu-dialyth;

(d) Inosiiicate (chain and band silicates), such as, for example, metasilicates (e.g. diopside) or amphiboles (e.g. tremolite);

(e) phyllosilicates (leaf and layer silicates) such as talc, kaolinite or mica (e.g. Mus-covit);

(f) Tectosilicates (framework silicates), such as feldspars and zeolites as well as ciathrasils or dodecasils (e.g. melanophlogite), thaumasite and neptunite.

In contrast to the ordered crystalline silicates, silicate glasses such as e.g. Soda or potash water glass used. These can be of natural origin (e.g. montmorillonite) or synthetic. In a further embodiment of the invention, aluminosilicates can also be used. Typical examples of alkali or alkaline earth silicates are sodium and / or potassium silicates with a modulus in the range from 1.0 to 3.0 and preferably 1.5 to 2.0.

Phosphonic acids are organic derivatives of the acid HP (0) (OH) 2; Phosphates are the salts and esters of these phosphonic acids. The preferred organic phosphonic acids or phosphonates are known chemical compounds which can be prepared, for example, by the Michaelis-Arbuzov reaction. For example, they follow formula (I)

O

(I)

I.

OR ²

in which R ¹ for an optionally substituted alkyl and / or alkenyl radical having 1 to 22, preferably 2 to 18 and in particular 6 to 12 carbon atoms and R ² for hydrogen, an alkali and / or alkaline earth metal, ammonium, alkylammonium and / or alkanolammonium or an optionally substituted alkyl and / or alkenyl radical having 1 to 22, preferably 2 to 18 and in particular 6 to 12 carbon atoms. Typical examples are optionally hydroxy-, nitrilo- and / or amino-substituted phosphonic acids such as ethylphosphonic acid, nitrilotris (methylenephosphonic acid), 1-amino or 1-hydroxyalkane-1,1-diphosphonic acids. In a preferred embodiment of the invention, amine oxide phosphonic acids are used which follow the formula (II)

0 CH ₃ H

II I I

HO-P- (CH ₂ ) m (CH) _n -N.> 0 (II)

1 I

OR ³ H

in which R ^{3 stands} for hydrogen, a (CH2) m (CHCH3) nNH2θ group or an alkali metal, for numbers from 1 to 4 and n for 0 or 1. Amine oxide phosphonic acids are builders or sequestering agents which are sold, for example, by Bozetto / IT under the Sequion® brand. For their preparation, one starts from aminophosphonic acids, which are converted to the amine oxide. For the purposes of the invention, both mono- and diamine oxides can be used in the form of the phosphonic acids or their salts, which follow the formula (II). Amine oxidephosphonic acids are preferably used in which R ^{3 is} hydrogen, m is 3 and n is 0 (amine oxide based on aminotri-methylenephosphonic acid).

Polyacrylic acid compounds suitable as sequestering agents are, in particular - the low molecular weight homopolymers of acrylic acid and methacrylic acid or their esters, compared to the high molecular weight representatives suitable as thickeners. In addition to the acids, esters of the acids can also be polymerized with alcohols having 1 to 4 carbon atoms. Polyacrylic acid compounds with a particularly advantageous stabilizing action are present as alkali salts and have an average molecular weight in the range from 1,000 to 10,000 and in particular 4,000 to 6,000 daltons.

Surfactants

To support the cleaning performance, the preparations can furthermore contain peroxide-stable surfactants, such as, for example, fatty acid salts, alkyl sulfates, alkyl sulfonates, alkylbenzenesulfonates, xylene sulfonates, sarcosinates, taurides, isethionates, sulfosuccinates, betaines, sugar esters and fatty acid Contain N-alkylglucamides. However, alkyl ether sulfates, amine oxides, alk (en) yl oligoglycosides or fatty alcohol polyglycol ethers are preferably used. The sum of all surfactants - based on the preparations - generally makes up 1 to 15 and preferably 5 to 10% by weight.

Alkyl ether sulfates are anionic surfactants which can be obtained by sulfating alkyl polyglycol ethers and subsequent neutralization. The alkyl ether sulfates which are suitable for the purposes of the invention follow the formula (III)

(III)

in which R ^{4 represents} an alkyl radical having 12 to 18, in particular 12 to 14, carbon atoms, n represents numbers 2 to 5, in particular 2 to 3 and X represents sodium or potassium. Typical examples are the sodium salts of sulfates of Ci2 / i4 coconut alcohol + 2, + 2,3- and + 3-EO adduct. The alkyl ether sulfates can have a conventional or narrow homolog distribution. The alkyl ether sulfates are preferably used in amounts of 1 to 8, preferably 1, 5 to 6 and in particular 2 to 4% by weight, based on the composition.

Amine oxides are also known substances, which are occasionally attributed to the cationic, but usually the nonionic surfactants. They are prepared from tertiary fatty amines, which usually have either one long and two short or two long and one short alkyl radical, and are oxidized in the presence of hydrogen peroxide. The amine oxides which are suitable as surfactant ingredients for the purposes of the invention follow the formula (IV)

R ⁶

(IV)

IR ⁷

in which R ^{5 is} a linear or branched alkyl radical having 12 to 18 carbon atoms and R ⁶ and R ⁷ independently of one another are R ⁵ or an optionally hydroxyl-substituted alkyl radical having 1 to 4 carbon atoms. Amine oxides of the formula (IV) in which R ⁵ and R ^{6 are} C12 / 14 or C12 / 18 coconut alkyl radicals and R ^{7 is} a methyl or a hydroxyethyl radical are preferably used. Also preferred are amine oxides of the formula (IV) in which R ^{5 is} a C12 / 14 or C12 / 18 cocoalkyl radical and R ⁶ and R ⁷ are methyl or Hydroxyethylrestes have. The amine oxides are preferably used in amounts of 1.5 to 6, preferably 2 to 4,% by weight, based on the composition.

Alkyl and alkenyl oligoglycosides are known nonionic surfactants which follow the formula (V)

R ⁸ 0. [G] _P (V)

in which R ^{8 is} an alkyl and / or alkenyl radical having 4 to 22 carbon atoms, G is a sugar radical having 5 or 6 carbon atoms and p is a number from 1 to 10. The alkyl and / or alkenyl oligo-glycosides, which are furthermore suitable as surfactant ingredients, can be derived from aldoses or ketoses with 5 or 6 carbon atoms, preferably glucose. The preferred alkyl and / or alkenyl oligoglycosides are thus alkyl and / or alkenyl oligoglucosides. The index number p in the general formula (V) indicates the degree of oligomerization (DP), ie the distribution of mono- and oligoglycosides, and stands for a number between 1 and 10. While p in a given compound must always be an integer and here can assume the values p = 1 to 6 in particular, the value p for a certain alkyl oligoglycoside is an analytically determined arithmetic parameter, which usually represents a fractional number. Alkyl and / or alkenyl oligoglycosides with an average degree of oligomerization p of 1.1 to 3.0 are preferably used. From an application point of view, those alkyl and / or alkenyl oligoglycosides are preferred whose degree of oligomerization is less than 1.7 and is in particular between 1.2 and 1.4. The alkyl or alkenyl radical R ⁸ can be derived from primary alcohols having 4 to 11, preferably 8 to 10, carbon atoms. Typical examples are butanol, capronalcohol, caprylic alcohol, capric alcohol and undecyl alcohol and their technical mixtures, as are obtained, for example, in the hydrogenation of technical fatty acid methyl esters or in the course of the hydrogenation of aldehydes from Roelen's oxosynthesis. Alkyl oligoglucosides of chain length C_-Cιo (DP = 1 to 3) are preferred, which are obtained as a preliminary step in the separation of technical Cβ-Ciβ-coconut fatty alcohol by distillation and can be contaminated with a proportion of less than 6% by weight of Ci2-alcohol and Alkyl oligoglucosides based on technical Cg / n oxo alcohols (DP = 1 to 3). The alkyl or alkenyl radical R ⁸ can also be derived from primary alcohols having 12 to 22, preferably 12 to 14, carbon atoms. Typical examples are lauryl alcohol, myristyl alcohol, cetyl alcohol, palmoleyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, elaidyl alcohol, petroselinyl alcohol, arachyl alcohol, gadoleyl alcohol, behenyl alcohol, erucyl alcohol, brassidyl alcohol and the technical mixtures described above, which can be obtained as well as their technical mixtures . Alkyl oligoglucosides based on hardened are preferred Ci2 / i4 coconut alcohol with a DP of 1 to 3. The glycosides are preferably used in amounts of 1.5 to 6, preferably 2 to 4% by weight, based on the composition.

The agents according to the invention can contain fatty alcohol polyglycol ethers of the formula (VI) as further surfactants,

(VI)

in which R ^{9 is} a linear or branched alkyl and / or alkenyl radical having 6 to 22 and preferably 12 to 18 carbon atoms and n is a number from 1 to 10. Typical examples are the addition products of on average 1 to 10 and preferably 2 to 5 moles of ethylene oxide with capron alcohol, caprylic alcohol, 2-ethylhexyl alcohol, capric alcohol, lauryl alcohol, isotridecyl alcohol, myristyl alcohol, cetyl alcohol, palmoleyl alcohol, stearyl alcohol, isostearyl alcohol, elaalyl alcohol, oleyl alcohol, oleyl alcohol Linolenyl alcohol, elaeostearyl alcohol, arachyl alcohol, gadoleyl alcohol, behenyl alcohol, erucyl alcohol and brassidyl alcohol and their technical mixtures, which are used, for example, in the high-pressure hydrogenation of technical methyl esters based on fats and oils or aldehydes from Roeien's oxosynthesis and as a monomer fraction in the dimerization of unsaturated fatty alcohols. Addition products of 2 to 5 moles of ethylene oxide onto technical fatty alcohols with 12 to 18 carbon atoms, such as, for example, coconut, palm, palm kernel or tallow fatty alcohol, are preferred. The polyglycol ethers can have a conventionally broad, but also a narrow homolog distribution (NRE). A particularly preferred polyglycol ether with a narrow homolog distribution is Ci2 / i4 coconut fatty alcohol + 2.5EO (NRE). With regard to an advantageous thickening, mixtures of fatty alcohol polyglycol ethers of linear and branched alkyl chains have proven to be advantageous. Particularly powerful preparations also contain mixtures of different fatty alcohol polyglycol ethers, in which one component has an HLB above and the other below 10. The polyglycol ethers are preferably used in amounts of 1 to 5, preferably 2 to 4% by weight, based on the composition.

Thickener

The use of electrolytes is a very simple and inexpensive way of adjusting the viscosity. However, it has been found that the presence of chloride ions in addition to peroxide can lead to pitting on certain textiles as a result of chlorine formation. For this reason, in a preferred embodiment of the invention, organic thickeners are used. used, which are, for example, polysaccharides, in particular xanthan gum, guar guar, agar agar, aiginates and tyloses, carboxymethyl cellulose and hydroxyethyl cellulose, and also higher molecular weight polyethylene glycol mono- and diesters of fatty acids, polyacrylates, (for example Carbopole® from Goodrich or Synthalene® from Sigma), polyacrylamides, polyvinyl alcohol and polyvinylpyrrolidone, clays such as Laponite® from Southern Clay Products or Zeothix® from Huber, surfactants such as ethoxylated fatty acid glycerides, esters of fatty acids with polyols such as pentaerythritol or Trimethylolpropane, fatty alcohol ethoxylates with a narrow homolog distribution or alkyl oligoglucosides, which can be added to the agents in amounts of 0.1 to 5% by weight, in particular 0.1 to 2% by weight.

Industrial applicability

The agents according to the invention are generally aqueous with a non-aqueous content of preferably 5 to 35% by weight and in particular 8 to 15% by weight and are particularly suitable for the treatment of textile fabrics, such as yarns, webs of fabric and in particular Textiles. They are usually used at low temperatures, i.e. in the cold wash area (approx. 15 to 25 ° C). The agents are not only characterized by excellent stain removal, but also reliably prevent deposits of lime and metal on the fibers and thus also prevent incrustation and yellowing. Although the actual use of the agents is aimed at removing stains during washing, they are basically also suitable for other purposes in which bleaching solutions are used, for example for cleaning and disinfecting hard surfaces.

In addition, the agents can contain fragrances, dyes and pigments in a total amount of 0.01 to 0.5% by weight, based on the agents. Typical examples of suitable peroxide-stable fragrances are: Citronellol (3,7-dimethyl-6-octen-1-ol), Dimethyloctanol (3,7-Dimethyloctanol-1), Hydroxycitronellol (3,7-Dimethyloctane-1,7-diol) , Mugol (3,7-dimethyl-4,6-octatrien-3-ol), myrcenol (2-methyl-6-methylene-7-octen-2-ol), terpinolene (p-mentho-1, 4 (8 ) -diene), ethyl 2-methylbutyrate, phenylpropyl alcohol, galaxolide (I.SAδ .δ-hexahydro e.δJ.δ.δ, - hexamethylcyclopental-2-benzopyran, tonalide (7-acetyl-1, 1, 3,4 , 4,6-hexamethyltetrahydronaphthalene), rose oxide, linalol oxide, 2,6-dimethyl-3-octanol, tetrahydroethyl-linalool, tetrahydroethyllinalylacetate, o-sec-butylcyclohexylacetate and isolonediphorene epoxide as well as isoborneal, dihydroterpene oil, isobornylacetyl acetate, dihydryl acetate. Other suitable fragrances are the substances mentioned in columns 3 and 4 of European patent application EP 0622451 A1 (Procter & Gamble). The color pigments include green chlorophthalocyanines (pigmo- sol® Green, Hostaphine® Green) or yellow Solar Yellow BG 300 (Sandoz) in question. In addition, the agents can contain other customary auxiliaries and additives, for example antioxidants such as phenols or phenol derivatives, for example butylated hydroxytoluene (BHT, 2,6-di-tert-butyl-4-methylphenol). The agents according to the invention are produced by stirring. If necessary, the product obtained can be decanted or filtered to remove foreign bodies and / or agglomerates. The agents also have a viscosity - measured at 20 ° C. in a Brookfield viscometer (spindle 1, 10 rpm) - above 100, preferably above 200 mPas.

Examples

Various hydrogen peroxidations were mixed with Tinopal® CBS-X capsules on the one hand and with the pure optical brightener on the other, filled into dark bottles and stored at 25 ° C. In each case 100 ml of the agents were assessed visually immediately after preparation and after 2 or 4 weeks of storage, then filled into beakers and treated with a magnetic stirrer for 1 min with poor stirring performance. Dirty tissue was then treated with the bleach solutions. The yellowing of the fabric was determined photometrically, the

Table 1

Bleach composition, yellowing and washing performance

0) Keltroi® T (from KeIco); 1) Carbopoi 497 (Goodrich); 2) trisodium salt of methylglycinediacetic acid (Fa.BASF); 3) loading: 90% by weight of Tinopal® CBS-X (4,4'-bis (2-sulfostyrene) biphenyl-di-sodium salt), coating material: sodium alginate; 4) 2,6-di-tert-butyl-4-methylphenol; 5) Pigmosol® Blue 6900 = water-dispersible copper phthalocyanine preparation = Pigment Blue 15 = C.1. 74160 (Fa.BASF)

Initial value of the soiled tissue served as the standard (100%). The water hardness of the liquor was 1000 ppm CaC, the hydrogen carbonate content was 0.013% by weight. The liquor ratio (tissue: water) was 1:50, the exposure time was 30 minutes at a temperature of 40 ° C. In addition, the washing performance was determined photometrically against a white standard. The results are summarized in Table 1. Examples 1 to 3 are according to the invention, examples V1 and V3 serve for comparison.

The preparations according to the invention with the microencapsulated optical brightener are homogeneous even after 4 weeks of storage, i.e. the capsules have not settled. While the comparative formulations, despite a 30% higher content of Tinopal® CBS-X, clearly deteriorate in their performance after 2 weeks due to chemical decomposition of the optical brightener, when the preparations according to the invention are subjected to mechanical stress, a sufficient amount of optical brightener is released even after storage. As a result, microencapsulation proves to be suitable for preventing chemical decomposition.

Claims

claims

1. Peroxide-containing preparations containing optical brighteners, characterized in that the optical brighteners are in microencapsulated form.

2. Preparations according to claim 1, characterized in that - based on the agent - contain 0.5 to 10 wt .-% hydrogen peroxide.

3. Preparations according to claims 1 and / or 2, characterized in that they contain - based on the agent - 0.1 to 10 wt .-% microcapsules containing optical brighteners.

4. Preparations according to at least one of claims 1 to 3, characterized in that they contain microcapsules, the shell substance is selected from the group formed by gum arabic, agar, agarose, maltodextrins, alginic acid, alginates, fats, fatty acids, cetyl alcohol , Collagen, chitosan, lecithin, gelatin, albumin, shellac, polysaccharides, celluloses, cellulose esters, cellulose ethers, starch ethers, starch esters, polyacrylates, polyamides, polyvinyl alcohols and polyvinyl pyrrolidone.

5. Preparations according to at least one of claims 1 to 4, characterized in that they contain microcapsules, the diameter of which is 0.01 to 10,000 microns along its greatest spatial extent.

6. Preparations according to at least one of claims 1 to 5, characterized in that they contain microcapsules which - based on the weight of the capsules - contain 1 to 95 wt .-% optical brighteners.

7. Preparations according to at least one of claims 1 to 6, characterized in that they further contain sequestering agents.

8. Preparations according to at least one of claims 1 to 7, characterized in that they also contain surfactants.

9. Preparations according to at least one of claims 1 to 8, characterized in that they further contain organic thickeners.

0. Preparations according to at least one of claims 1 to 9, characterized in that they have a Brookfield viscosity above 100 mPas.