EP0358109A2 - Use of acyl derivatives of dihydroxydioxanes as bleach activators, and detergents containing the same - Google Patents

Abstract

Use of compounds of the formula <IMAGE> in which R¹ is, for example, C1 to C8 alkyl, optionally substituted alkyl or C3 to C8 alkenyl, R², R³ e.g. H or C1- to C16-alkyl mean as bleach activators for peroxides in detergents and detergents which contain compounds of the formula I.

Description

In the usual detergents, peroxides such as sodium perborate are used as typical bleaching agents. The bleaching process requires temperatures of approx. 80 to 85 ° C. This requires a relatively large amount of energy and can lead to fiber damage and discoloration in the case of colored textiles. Since the peroxides react slowly at the desired lower temperatures, such as 40 to 60 ° C., bleach activators are added to the peroxide-containing detergents.

The most widely used bleach activators include peracetylated compounds of polyamines such as tetracetylethylenediamine (TAED) or of polyols such as pentaacetylglucose (PAG). In practice, the TAED sets the standard. However, it has the disadvantage of being a nitrogen-containing compound, which should be avoided as much as possible because of the eutrophication of the waters by nitrogenous degradation products. Due to their reactivity, only two of the four acetyl groups in the molecule can serve as peroxide activators. In the nitrogen-free PAG, only two and a half of the five acetyl groups can be used for peroxide activation on average. The sodium salt of isononanoyloxibenzenesulfonic acid used, for example, as a bleach activator has the known disadvantage of phenol derivatives and, moreover, is not technically easy to prepare as a phenolsulfonic acid derivative.

From U.S. Patent 3,291,624 it is known to use acetylated derivatives of dialdehyde hemiacetals, e.g. 2,3-diacetoxi-1,4-dioxane, to be used as a hardener for gelatin preparations in films instead of formaldehyde. The 2,3-diacetoxi-1,4-dioxane is obtained from 2,3-dichlorodioxane by reaction with potassium acetate in glacial acetic acid, cf. Boeseken et al., J. Amer. Chem. Soc., Vol. 55, 1284ff (1933). Such a process is not easily feasible on an industrial scale because of the hydrochloric acid to be neutralized.

From J. Am. Soc., Volume 77, 1285 ff (1955) it is known that when 1-butanol is reacted with aqueous solutions of glyoxal which contain ethylene glycol, 2,3-di-n-butoxy-1,4- dioxane is formed. It is also known from Tetrahedron Vol. 40, 2011 ff (1984) that 2,3-dihydroxy-1,4-dioxane can be converted into two isomeric 2,3-diacetoxy-1,4-dioxanes by the action of acetic anhydride / pyridine .

The object of the invention is to provide new nitrogen-free bleach activators for detergents in which as far as possible all the acyl groups present have a peroxide-activating effect and which are technically easy to produce.

in der die Reste R¹ gleich sind und einen geradkettigen oder verzweigten Alkylrest mit 1 bis 16 C-Atomen, der gegebenenfalls eine oder mehrere ole­finische Doppelbindungen enthält und/oder durch eine Carboxylgruppe, durch eine Alkoxigruppe mit 1 bis 4 C-Atomen im Alkyl oder durch einen gegebe­nenfalls ein- oder zweifach durch Alkyl mit 1 bis 3 C-Atomen, Alkoxy mit 1 bis 3 C-Atomen im Alkyl oder durch eine Carboxylgruppe substituierten Phenylrest substituiert ist, wobei die vorhandenen Carboxylgruppen in neu­tralisierter Form vorliegen, und R² und R³ gleich oder verschieden sind und Wasserstoffatome, einen gesättigten geradkettigen oder verzweigten Alkylrest mit 1 bis 16 C-Atomen, wobei die Summe der C-Atome der beiden Alkylreste R² und R³ die Zahl 16 nicht übersteigt und die Alkylreste R² und R3 als Substituenten eine Carboxylgruppe, vorliegend in neutralisier­ter oder teilneutralisierter Form, oder durch einen Phenylrest substitu­iert sein können, eine Carboxylgruppe, in neutralisierter oder veresterter Form vorliegend, oder einen Rest der Formel

-CH₂-O-

-R⁴ ,
wobei R⁴ gleich dem Rest R¹ ist, bedeuten, als Bleichaktivatoren für Peroxide in Waschmitteln.The object is achieved according to the invention by using compounds of the formula

in which the radicals R 1 are the same and a straight-chain or branched alkyl radical having 1 to 16 carbon atoms, which optionally contains one or more olefinic double bonds and / or by a carboxyl group, by an alkoxy group having 1 to 4 carbon atoms in the alkyl or by an optionally mono- or disubstituted by alkyl having 1 to 3 carbon atoms, alkoxy having 1 to 3 carbon atoms in the alkyl or by a carboxyl group substituted phenyl radical, the carboxyl groups present being in neutralized form, and R² and R³ being the same or are different and are hydrogen atoms, a saturated straight-chain or branched alkyl radical having 1 to 16 carbon atoms, the sum of the carbon atoms of the two alkyl radicals R² and R³ not exceeding 16 and the alkyl radicals R² and R3 as substituents a carboxyl group, in the present case in neutralized or partially neutralized form, or may be substituted by a phenyl radical, a carboxyl group, in neutral sied or esterified form present, or a radical of the formula

-CH₂-O-

-R⁴,
where R⁴ is the same as R¹, mean as bleach activators for peroxides in detergents.

The particular advantages of the new bleach activators are that practically all existing acyl groups can be used as bleach activators. The products therefore have a very good effect.

mit Me = Na oder K von Interesse. Als Alkylreste kommen z.B. Methyl, Ethyl, 2-Ethylhexyl, 2-Propyl und 3,5,5-Trimethylhexyl in Betracht. In diesen Fällen bedeuten die Reste R² und R³ Wasserstoff oder einen Alkyl­rest mit 1 bis 16, bevorzugt 1 bis 4 C-Atomen, z.B. Methyl, Ethyl, Propyl, Butyl, Pentyl, Hexyl, Carboxyl, Phenyl, Dodecyl und Hexadecyl. Besonders bevorzugt verwendet man solche Verbindungen der Formel I, in der einer der Substituenten R² und R³ für Wasserstoff steht und der andere C₁- bis C₁₆-­Alkyl bedeutet.The compounds of formula I are preferably used as bleach activators in which R¹ = C₁ - to C₈-alkyl, C₃- to C₈-alkyl or - (CH₂) ₂-COOMe, - (CH₂) ₃-COOMe - (CH₂) ₄ · COOMe or -CH = CH-COOMe and Me represents Na, K or ammonium. Furthermore, the meanings for R¹ are phenyl and

with Me = Na or K of interest. Examples of suitable alkyl radicals are methyl, ethyl, 2-ethylhexyl, 2-propyl and 3,5,5-trimethylhexyl. In these cases, the radicals R² and R³ are hydrogen or an alkyl radical having 1 to 16, preferably 1 to 4, carbon atoms, for example methyl, ethyl, propyl, butyl, pentyl, hexyl, carboxyl, phenyl, dodecyl and hexadecyl. Compounds of the formula I in which one of the substituents R² and R³ is hydrogen and the other is C₁- to C₁--alkyl are particularly preferably used.

In accordance with the meanings mentioned and emphasized, the following can be mentioned, for example, as compounds of the formula I to be used according to the invention:
2,3-diacetoxy-1,4-dioxane, 2,3-diacetoxy-5-methyl-1,4-dioxane, 2,3-diacetoxy-5-acetoxymethyl-1,4-dioxane, 2,3-diacetoxy- 5,6-dimethyl-1,4-dioxane, 2,3-diacetoxy-5,6-benzo-1,4-dioxane, 2,3-dipivaloyl-1,4-dioxane, 2,3-dipivaloyl-5- methyl-1,4-dioxane, 2,3-diisononanoyl-1,4-dioxane, 2,3-di-phenylacetoxy-1,4-dioxane, 2,3- [2-ethylhexanoyl] -1,4-dioxane, 2,3-di-stearyl-1,4-dioxane, 2,3-di-benzoyl-1,4-dioxane. The use of 2,3-diacetoxy-1,4-dioxane is particularly preferred.

in der die Reste R² und R³ die für die Reste R² und R³ in Formel I ange­gebenen Bedeutungen aufweisen und darüber hinaus einer der Reste R² oder R³ einen Hydroxymethylrest darstellen kann, mit einer wäßrigen Lösung von Glyoxal bei Temperaturen von 20 bis 80°C und in einem pH-Wertbereich von 2 bis 6 zu einem Zwischenprodukt der Formel

in dem R² und R³ die für die Formel II angegebenen Bedeutungen aufweisen, umsetzt, aus der erhaltenen Lösung das Wasser und gegebenenfalls verwen­detes Lösemittel unter vermindertem Druck bei Temperaturen von 50 bis 80°C abdestilliert und den erhaltenen Rückstand in an sich üblicher Weise mit Acetanhydrid und Na-Acetat, Pyridin, H₂SO₄ oder einer organischen Säure als Katalysator verestert.The compounds of formula I are known. They can advantageously be manufactured technically extremely simply by using a compound of the formula

in which the radicals R² and R³ have the meanings given for the radicals R² and R³ in formula I and, moreover, one of the radicals R² or R³ can be a hydroxymethyl radical, with an aqueous solution of glyoxal at temperatures from 20 to 80 ° C and in a pH range from 2 to 6 to an intermediate of the formula

in which R² and R³ have the meanings given for the formula II, the water and any solvent used are distilled off under reduced pressure at from 50 to 80 ° C. and the residue obtained in a conventional manner with acetic anhydride and Na acetate, pyridine, H₂SO₄ or an organic acid esterified as a catalyst.

The compounds of formula II are preferably reacted in an equimolar amount with glyoxal. However, they can also be used in excess amounts of up to 50 mol%. The glyoxal is used in the form of its customary aqueous 20 to 50% by weight solutions, preferably in the form of the technical approx. 40% by weight aqueous solution. The preferred temperatures for the reaction of the compounds of formula II with glyoxal are 30 to 70 ° C. The reaction is preferably carried out in a pH range from 3 to 5. To maintain an appropriate or preferred pH range, the reaction to the intermediate of formula III can be carried out in the presence of an acid such as sulfuric acid, phosphoric acid or para-toluenesulfonic acid as a catalyst. The reaction can optionally be carried out in the presence of a solvent such as toluene.

-O-

-R¹      (IV),
in der die Substituenten R¹ die in Formel I angegebene Bedeutung haben. Die Veresterung der Verbindungen der Formel III mit den Verbindungen der Formel IV wird beispielsweise in Gegenwart von Schwefelsäure als Kataly­sator oder in dem System Acylanhydrid/Natriumacetat, beziehungsweise Acylanhydrid/Pyridin vorgenommen. Die Veresterung kann selbstverständlich auch durch Reaktion der Verbindungen der Formel III mit Säurehalogeniden, vorzugsweise Carbonsäurechloriden, vorgenommen werden.Appropriate process conditions for the esterification are reaction with a corresponding acyl anhydride of the formula

R¹-

-O-

-R¹ (IV),
in which the substituents R¹ have the meaning given in formula I. The esterification of the compounds of formula III with the compounds of formula IV is carried out, for example, in the presence of sulfuric acid as a catalyst or in the system acyl anhydride / sodium acetate or acyl anhydride / pyridine. The esterification can of course also be carried out by reacting the compounds of the formula III with acid halides, preferably carboxylic acid chlorides.

The bleach activators of the formula I mentioned above are particularly suitable for powdered or anhydrous liquid detergents. They are expediently used in amounts of 2 to 12% by weight, preferably 4 to 8% by weight, based on the detergent. The detergent formulations are obtained by mixing the individual components or by mixing prefabricated formulations. The connections of the Formula I can be used to prepare the detergents in the form of an aqueous solution or as a powder or granules.

The invention therefore also relates to detergents which contain a compound of the formula I as a bleach activator for peroxides.

Powdery or anhydrous liquid detergent formulations are preferred. Because of the sensitivity to hydrolysis of the compounds of formula (I), the detergents should contain as little free water as possible in the interest of the best possible shelf life. With liquid detergents, this means practically complete freedom from water within the limits of what is technically possible, i.e. Water content of at most about 0.5%. In the case of powder detergents, the tolerance limit for unbound water is significantly higher, namely a maximum of about 10%; any water of crystallization present in the powder detergents is bound so tightly that it is harmless to the compounds of the formula (I).

Phosphate-containing and phosphate-free formulations come into consideration as framework regulations for suitable detergent formulations with the bleach activators to be used according to the invention. In addition to the bleach activators of the formula I, the detergents and cleaning agents each contain 6 to 25% by weight, based on the total weight, of surfactants and further customary constituents, such as 5 to 50% by weight builders and optionally co-builders, 5 to 35% by weight. Bleaching agents and optionally 3 to 30% by weight of auxiliaries, such as enzymes, foam regulators, corrosion inhibitors, optical brighteners, fragrances, dyes or formulation auxiliaries, such as sodium sulfate. In the following, the components of detergents usually used for the production of detergent formulations are mentioned as examples:

Suitable surfactants are those which contain at least one hydrophobic organic radical and one water-solubilizing anionic, zwitterionic or nonionic group in the molecule. The hydrophobic radical is usually an aliphatic hydrocarbon radical with 8 to 26, preferably 10 to 22 and in particular 12 to 18 carbon atoms, or an alkyl aromatic radical with 6 to 18, preferably 8 to 16, aliphatic carbon atoms.

Suitable synthetic anionic surfactants are in particular those of the sulfonate, sulfate or synthetic carboxylate type.

The surfactants of the sulfonate type are alkylbenzenesulfonates with 4 to 15 carbon atoms in alkyl, mixtures of alkene and hydroxyalkanesulfonates and disulfonates, such as are obtained, for example, from monoolefins with terminal or internal double bonds by sulfonation with gaseous sulfur trioxide and subsequent alkaline or acidic hydrolysis of the sulfonation products receives. Also suitable are alkanesulfonates which can be obtained from alkanes by sulfochlorination or sulfoxidation and subsequent hydrolysis or neutralization or by bisulfite addition to olefins. Other useful sulfonate type surfactants are the esters of α-sulfo fatty acids, e.g. the α-sulfonic acids from hydrogenated methyl or ethyl esters of coconut, palm kernel or tallow fatty acid.

Suitable sulfate type surfactants are the sulfuric acid monoesters of primary alcohols, e.g. from coconut fatty alcohols, tallow fatty alcohols or oleyl alcohol, and those from secondary alcohols. Sulfated fatty acid alkanolamines, fatty acid monoglycerides or reaction products of 1 to 4 moles of ethylene oxide with primary or secondary fatty alcohols or alkylphenols are also suitable.

Other suitable anionic surfactants are the fatty acid esters or amides of hydroxy or aminocarboxylic acids or sulfonic acids, e.g. the fatty acid sarcosides, glycolates, lactates, taurides or isothionates.

The anionic surfactants can be in the form of their sodium, potassium and ammonium salts and also as soluble salts of organic bases, such as mono-, di- or triethanolamine. The usual soaps, i.e. Salts of natural fatty acids should not go unmentioned.

As nonionic surfactants (Nonionics) e.g. Addition products of 3 to 40, preferably 4 to 20, moles of ethylene oxide and 1 mole of fatty alcohol, alkylphenol, fatty acid, fatty amine, fatty acid amide or alkanesulfonamide can be used. The addition products of 5 to 16 moles of ethylene oxide with coconut oil or tallow fatty alcohols, with oleyl alcohol or with synthetic alcohols with 8 to 18, preferably 12 to 18 carbon atoms, and with mono- or dialkylphenols with 6 to 14 carbon atoms in are particularly important the alkyl residues. In addition to these water-soluble nonionics, non-fully or not completely water-soluble polyglycol ethers with 1 to 4 ethylene glycol ether residues in the molecule are also of interest, in particular if they are used together with water-soluble nonionic or anionic surfactants.

Furthermore, the non-ionic surfactants are the water-soluble adducts of ethylene oxide with polypropylene glycol containing 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups ether, alkylenediaminopolypropylene glycol and alkylpolypropylene glycols with up to 10 carbon atoms in the alkyl chain can be used, in which the polypropylene glycol ether chain acts as a hydrophobic radical.

Nonionic surfactants of the amine oxide or sulfoxide type can also be used.

The foaming power of the surfactants can be increased or decreased by combining suitable types of surfactants. A reduction can also be achieved by adding non-surfactant-like organic substances.

Suitable builder substances are, for example: washing alkalis, such as sodium carbonate and sodium silicate, or complexing agents, such as phosphates, or ion exchangers, such as zeolites, and mixtures thereof. These builders and builders have the task of eliminating the hardness ions, which come partly from water, partly from dirt or the textile material, and to support the surfactant effect. In addition to the above Builder substances can also be contained in the builder, so-called co-builders. In modern detergents, the co-builders have the task of adopting some properties of the phosphates, e.g. Sequestering effect, dirt-carrying capacity, primary and secondary washing effect.

In the builder e.g. water-insoluble silicates, as described for example in DE-PS 24 12 837, and / or phosphates. Pyrophosphate, triphosphate, higher polyphosphates and metaphosphates can be used from the group of phosphates. Organic complexing agents containing phosphorus, such as alkane polyphosphonic acids, amino and hydroxyalkane polyphosphonic acids and phosphonocarboxylic acids, are also suitable as further detergent ingredients. Examples of such detergent additives are e.g. the following compounds: methane diphosphonic acid, propane-l, 2,3-triphosphonic acid, butane-1,2,3,4-tetraphosphonic acid, polyvinylphosphonic acid, 1-aminoethane-1,1-diphosphonic acid, 1-amino-1-phenyl1,1- diphosphonic acid, aminotrismethylene-triphosphonic acid, methylamino- or ethylaminobismethylene-diphosphonic acid, ethylenediaminotetramethylene-tetraphosphonic acid, diethylene-triaminopentamethylene-pentaphosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid, phosphonoacetic and phosphonopropionic acid, mixed polymers or partially or acrylate-derived from vinylphosphonate and / or maleated acid from vinylphosphonate and theirs or methane-derived maleinates from vinylphosphonate and partially or maleated from vinylphosphonic acid and vinyl or phosphonic acid from vinylphosphonate and / or maleated acid from vinylphosphonate and / or maleated from vinylphosphonic acid and vinyl / phosphonic acid and from malphased or vinylphosphonic acid from vinylphosphonate and / or maleated.

Other organic compounds which act as complexing agents for calcium ions and can be present in detergent formulations are polycarboxylic acids, hydroxycarboxylic acids and aminocarboxylic acids, which are mostly used in the form of their water-soluble salts.

Examples of polycarboxylic acids are dicarboxylic acids of the general formula HOOC- (CH₂) _m -COOH with m = O-8, also maleic acid, methylene malonic acid, citraconic acid, mesaconic acid, itaconic acid, non-cyclic polycarboxylic acids with at least 3 carboxyl groups in the molecule, such as tricarballylic acid, aconitic acid, Ethylene tetracarboxylic acid, 1,1,3-propane-tetracarboxylic acid, 1,1,3,3,5,5-pentane-hexacarboxylic acid. Hexane hexacarboxylic acid, cyclic di- or polycarboxylic acids, such as cyclopentane tetracarboxylic acid, cyclohexane hexacarboxylic acid, tetrahydrofuran tetracarboxylic acid, phthalic acid, terephthalic acid, benzene tri-, tetra- or pentacarboxylic acid and mellitic acid.

Examples of hydroxymono- or polycarboxylic acids are glycolic acid, lactic acid, malic acid, tartronic acid, methyltartronic acid, gluconic acid, glyceric acid, citric acid, tartaric acid, salicylic acid.

Examples of aminocarboxylic acids are glycine, glyclglycine, alanine, asparagine, glutamic acid, aminobenzoic acid, iminodi- or triacetic acid, hydroxyethyliminodiacetic acid, ethylenediaminotetraacetic acid, hydroxyethyl-ethylenediamine-triacetic acid, diethylenetriamine-pentaacetic acid and polymerisation of a, e.g. of acetic acid, succinic acid, tricarballylic acid, and subsequent saponification, or by condensation of polyamines with a molecular weight of 500 to 10,000 with chloroacetic or bromoacetic salts.

Polymeric carboxylic acids are preferably used as co-builders. These polymeric carboxylic acids include the carboxymethyl ethers of sugar, starch and cellulose.

Among the polymeric carboxylic acids e.g. the polymers of acrylic acid, maleic acid, itaconic acid, mesaconic acid, aconitic acid, methylene malonic acid, citraconic acid and the like, the copolymers of the above-mentioned carboxylic acids with one another, e.g. Copolymers of acrylic acid and maleic acid (especially those in a ratio of 70:30 and a molecular weight of 70,000), or the 1: 1 copolymers of maleic anhydride and methyl vinyl ether of a molecular weight of 70,000 or the copolymers of maleic anhydride and ethylene or propylene play a special role.

The co-builders can also contain dirt carriers which keep the dirt detached from the fibers suspended in the liquor and thus inhibit graying. Water-soluble colloids, mostly of an organic nature, are suitable for this, such as, for example, the water-soluble salts of polymeric carboxylic acids, glue, gelatin, salts of ether carboxylic acids or ether sulfonic acids of starch or cellulose or salts of acidic acids Sulfuric acid esters of cellulose or starch. Water-soluble polyamides containing acidic groups are also suitable for this purpose. Soluble starch preparations and starch products other than those mentioned above can also be used, such as degraded starch, aldehyde starches, etc. Polyvinylpyrrolidone can also be used.

Bleaching agents are especially hydrogen peroxide and derivatives or active chlorine-providing compounds. Sodium perborate hydrates, such as NaBO₂ · H₂O₂ · 3H₂O and NaBO₂ · H₂O₂, are of particular importance among the compounds which serve as bleaching agents and supply H₂O₂ in water. But there are also other H₂O₂ supplying borates. These compounds can be partially or completely replaced by other active oxygen carriers, in particular by peroxyhydrates, such as peroxycarbonates, peroxyphosphonates, citrate perhydrates, urea-H₂O₂- or melamine-H₂O₂-compounds as well as by H₂O₂-delivering peracid salts, e.g. Persulfates, perbenzoates or peroxyphthalates can be replaced.

Preparation of the compounds of formula I to be used according to the invention Bleach activator 1

5 moles of ethylene glycol are stirred with 40% by weight aqueous glyoxal solution at pH 4 for 2 hours at 70 ° C. and then the water is distilled off at 70 ° C. and 100 mbar on a rotary evaporator. The melt obtained crystallizes slowly or can be crystallized from ethanol. Melting point 97 ° C, the yield of 594 g corresponds to 99% of theory of 2,3-dihydroxy-1,4-dioxane.

0.5 mol of dihydroxy-1,4-dioxane are slowly introduced into 1.1 mol of acetic anhydride with 2 drops of H₂SO₄ with stirring. The reaction mixture is stirred at 40 ° C. for 4 hours. After cooling, the reaction mixture is poured onto ice water, the solid substance obtained is filtered off and dried. Melting point 106 ° C, the yield of 51 g corresponds to 50% of theory of 2,3-diacetoxi-1,4-dioxane.

Bleach activator 2

1 mol of 1,2-propanediol are stirred for 3 hours at 50 ° C. with 40% by weight aqueous glyoxal solution. The water is then distilled off at 70 ° C. and 100 mbar. 125 g (93% of theory) of 2,3-dihydroxi-5-methyl-1,4-dioxane are obtained in the form of a clear, colorless oil which crystallizes on prolonged standing.

0.25 mol of 2,3-dihydroxi-5-methyl-1,4-dioxane in 80 ml of pyridine, which contains catalytic amounts of dimethylaminopyridine, are placed in a flask equipped with a stirrer. At room temperature, 0.55 mol of pivaloyl chloride is added dropwise. After stirring for 12 hours at 80 ° C., the reaction mixture is poured onto ice water and the aqueous phase is extracted three times with 100 ml of diethyl ether each time. The organic phase is washed successively with 150 ml of 10% strength by weight hydrochloric acid and 150 ml of 5% strength by weight sodium hydrogen carbonate solution, then dried and the solvent is distilled off in vacuo. 63 g (75% of theory) of 2,3-dipivaloyl-5-methyl-1,4-dioxane remain in the form of a crystalline residue which, after recrystallization from methanol, has a melting point of 123 ° C.

Bleach activator 3

0.2 mol of the 2,3-dihydroxi-1,4-dioxane prepared according to Example 1 are esterified with 0.4 mol of isonanonic acid chloride in pyridine. After working up and recrystallization from diethyl ether / methanol, 51 g (59% of theory) of 2,3-di-isononanoyl-1,4-dioxane remain as a white solid. The spectroscopic data are consistent with the structure.

Bleach activator 1

can also be prepared by introducing 1 mol of acetic anhydride and 0.05 mol of Na acetate. 2,3-Dihydroxidioxane is then introduced at 40 ° C. and stirring is continued for 4 hours at 60 ° C. The solution is evaporated to dryness. A mixture of cis / trans-2,3-diacetoxi-1,4-dioxane in a ratio of 1: 1 is obtained.

The suitability of the bleach activators produced is determined by washing and bleaching tests on artificially soiled cotton fabrics. Artificial, bleachable stains suitable for test purposes have been found to be cotton fabrics treated with tea or red wine. The results are described in Table 1. The bleaching tests were carried out at 20 ° C, 38 ° C and 60 ° C. The test conditions were as follows: Washing machine: Launder-O-meter Water hardness: 16.8 ° d (approx: Mg 4: 1) Amount of fabric: 20 g Fleet quantity: 250 ml Detergent concentration: 8 g / l Washing time: 30 min Detergent composition (powder): 6.25% C₁₂ alkylbenzenesulfonate 4.7% Tallow fatty alcohol reacted with 11 moles of ethylene oxide 2.8% Soap 15% Na perborate tetrahydrate 7.2% Nasilicate 3.6% Mg sulfate · 7 H₂O 1.0% Carboxymethyl cellulose 0.2% Ethylenediaminetetraacetic acid, sodium salt 20.0% Zeolite A 10.0% Na carbonate 17.5% Na sulfate 4% Bleach activator rest Water to 100%

The bleaching effect was determined by measuring the degree of whiteness with an Elrepho photometer. A detergent in which sodium sulfate was used instead of the bleach activator was used as a control test.

The washing results show that the activators to be used according to the invention markedly improve the bleaching effect. The effect is clearly pronounced at all of the three temperatures tested. Compared to activators that are already used in commercially available detergents, there are clear advantages at RT (20 ° C) in the activating effect. At higher washing temperatures, the effect is better than that of ISONOBS (3,5,5-trimethylhexanoylbenzenesulfonic acid Na salt). Comparable results with TAT cannot be obtained with the same concentration. Table 1 % Remission 20 ° C 38 ° C 60 ° C tea red wine tea red wine tea red wine 1. without activator 57.1 62.2 63.3 65.3 66.5 68.6 Bleach activator 1 59.7 63.6 66.1 66.6 69.3 70.5 2. without activator 58.2 56.7 60.4 60.6 68.0 66.4 Bleach activator 3 58.9 59.0 61.4 62.2 69.0 67.8 3. without activator 62.4 54.5 73.3 59.5 80.1 68.6 Bleach activator 1 68.2 56.8 75.4 62.9 80.9 72.1 TAED ¹⁾ 65.5 55.7 77.1 65.5 82.5 75.8 ISONOBS ²⁾ 65.7 54.6 76.0 61.0 81.3 69.9 ¹⁾ TAED = tetraacetylethylenediamine ²⁾ ISONOBS = Na salt of isononanoyloxibenzenesulfonic acid

Claims (4)

1. Use of compounds of formula I.

in which the radicals R 1 are identical and a straight-chain or branched alkyl radical having 1 to 16 carbon atoms, which optionally contains one or more olefinic double bonds and / or by an alkoxy group having 1 to 4 carbon atoms in the alkyl, by an optionally one or is substituted twice by alkyl having 1 to 3 carbon atoms or alkoxy having 1 to 3 carbon atoms in the alkyl or by a carboxyl group-substituted phenyl radical or by a carboxyl group, the carboxyl groups present being in neutralized form, and R² and R³ being identical or are different and are hydrogen atoms, a saturated straight-chain or branched alkyl radical having 1 to 16 carbon atoms, the sum of the carbon atoms of the two alkyl radicals R² and R³ not exceeding the number 16 and the alkyl radicals R² and R³ as substituents a carboxyl group, in the present case in neutralized or esterified form, or may be substituted by a phenyl radical, a carboxyl group, in neutralized ter or esterified form, or a radical of the formula

-CH₂-O-

-R⁴,
where R⁴ is the same as R¹, mean as bleach activators for peroxides in detergents. 2. Use according to claim 1, characterized in that one uses compounds of formula I in which
R¹ = C₁ to C₈-alkyl, C₃- to C₈-alkenyl, - (CH₂) ₂-COOMe, - (CH₂) ₃-COOMe, - (CH₂) ₄-COOMe, -CH = CH-COOMe,

Me = Na, K, ammonium and
R², R³ = H, C₁ to C₁₆ alkyl
mean. 3. Use according to claim 1, characterized in that compounds of the formula I are used in which R¹ = C₁- to C₈-alkyl and R², R³ = H. 4. Powdery or anhydrous liquid detergent containing effective amounts of at least one compound of the formula I as bleach activator for peroxides.