EP2737042B2 - Washing or cleaning method with electrochemically activatable mediator compound - Google Patents

Description

The present invention relates to a washing or cleaning process using bleach-active species generated from specific organic mediator compounds.

Inorganic peroxygen compounds, particularly hydrogen peroxide and solid peroxygen compounds which dissolve in water to liberate hydrogen peroxide, such as sodium perborate and sodium carbonate perhydrate, have long been used as oxidizing agents for disinfection and bleaching purposes. The oxidizing effect of these substances in dilute solutions depends strongly on the temperature; for example, with H ₂ O ₂ or perborate in alkaline bleaching liquors, sufficiently rapid bleaching of soiled textiles is only achieved at temperatures above about 80.degree. At lower temperatures, the oxidizing effect of the inorganic peroxygen compounds can be improved by adding so-called bleach activators, which are able to supply peroxocarboxylic acids under the perhydrolysis conditions mentioned and for which numerous proposals, especially from the substance classes of the N- or O-acyl compounds, for example reactive Esters, polyacylated alkylenediamines, in particular N,N,N',N'-tetraacetylethylenediamine (TAED), acylated glycolurils, in particular tetraacetylglycoluril, N-acylated hydantoins, hydrazides, triazoles, hydrotriazines, urazoles, diketopiperazines, sulfurylamides and cyanurates, and also carboxylic acid anhydrides, in particular phthalic anhydride, carboxylic acid esters, in particular sodium nonanoyloxybenzenesulfonate (NOBS), sodium isononanoyloxybenzenesulfonate, O-acylated sugar derivatives such as pentaacetyl glucose, and N-acylated lactams such as N-benzoylcaprolactam, have become known in the literature. By adding these substances, the bleaching effect of aqueous peroxide liquors can be increased to such an extent that, even at temperatures around 60°C, essentially the same effects occur as with the peroxide liquor alone at 95°C.

In recent years, in efforts to find energy-saving washing and bleaching processes, application temperatures well below 60° C., in particular below 45° C. down to cold water temperature, have also become more important.

At these low temperatures, the effect of the previously known activator compounds generally diminishes noticeably. There has therefore been no lack of efforts to develop more effective activators for this temperature range. The use of transition metal compounds, in particular transition metal complexes, to increase the oxidizing power of peroxygen compounds or atmospheric oxygen in detergents and cleaning agents has also been proposed on various occasions. The transition metal compounds proposed for this purpose include, for example, manganese, iron, cobalt, ruthenium or molybdenum salen complexes, manganese, iron, cobalt, ruthenium or molybdenum carbonyl complexes, manganese, iron, cobalt, ruthenium, molybdenum, titanium, vanadium and copper complexes with nitrogen containing tripod ligands, and manganese complexes with polyazacycloalkane ligands such as TACN. A disadvantage of such metal complexes, however, is that they either especially at low temperature, sometimes do not have sufficient bleaching power or, with sufficient bleaching power, the colors of the material to be washed or cleaned and possibly even the material itself, for example the textile fibers, can be undesirably damaged.

From the international patent application WO 2009/106406 A1 discloses a process for removing stains from textiles using bleaching species which are formed by hydrolysis of common bleaching agents such as hypochlorite and H ₂ O ₂ or by electrolysis of reducing sugars. In Electrochimica Acta 47 (2001) 799-805 the violet acid-mediated electrochemical bleaching of pulps for textile production is investigated. From the patent application DE 198 43 571 A1 discloses a process for bleaching indigo-dyed denim fabrics using electrochemically oxidized organic substances including violet acid.

Surprisingly, it has now been found that bleach-active species can be produced from organic mediator compounds by means of electrolysis, which species have an excellent bleach-boosting effect and enhance the cleaning performance of detergents and cleaning agents, in particular against bleachable soiling.

An object of the invention is accordingly a method for washing textiles or for cleaning hard surfaces, in particular for machine cleaning of dishes, using a bleach-active species generated electrolytically by a redox reaction from an organic mediator compound, characterized in that the mediator compound in the Production of the bleach-active species donates an electron, the organic mediator compound being an aliphatic, cycloaliphatic, aromatic or araliphatic compound which may contain heteroatoms and which has a group N-OH, N-OR, a nitroxyl radical NO and/or a group NO ^- with a counter cation M ⁺ or ½ M ²⁺ , where R is an alkyl group having in particular 1 to 4 carbon atoms and M is hydrogen, an alkali metal or an alkaline earth metal, and in particular a hydroxamic acid such as N-hydroxyphthalimide, an N-hydroxyheteroaromatic such as 1-hydroxyindole, 1 -hydroxybenzimidazole and 1-hydroxybenzotriazole Radical of a sterically hindered N-hydroxy compound such as (2,2,6,6-tetramethylpiperidin-1-yl)oxyl, and an oximidoketone such as violet acid and N,N'-dimethylviolet acid, and wherein the mediator compound contained liquor is continuous or on or is electrolyzed several times for specific periods of time, in particular 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes.

The bleach-active species can be produced in a simple manner by subjecting an aqueous system which contains the mediator compound to an electrical potential difference between at least two electrodes, so that the mediator compound releases an electron. Without wanting to be bound by this theory, it is conceivable that the free radical species generated in this way gets to the dirt with the aqueous liquor and removes an electron from the soiling, thereby ultimately turning the soiling into a less colored and/or more water-soluble and/or dispersible material arises. The potential difference is preferably 0.2 V to 5 V, in particular 1 V to 3 V. The mediator compound is preferably reformed from the bleach-active species by reaction with the soiling, so that a reversible redox system is present. It is possible to electrolyze the liquor containing the mediator compound continuously or one or more times for specific periods of time, for example 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes. The generation of the bleach-active species is also possible in that the mediator compound, in particular when using a conventional flushing device, passes through an electrolysis device before it enters the chamber of a washing machine or dishwasher, in particular in an aqueous solution or slurry flows through an electrolysis cell that is in the feed line can be mounted inside or outside the machine. Alternatively, it is possible at the beginning of the process to allow other active substances, for example enzymes, to perform their work unaffected and only to start the bleaching effect later by switching on the electrolysis device.

In a preferred embodiment of the invention, the electrolysis device is installed inside a washing machine or dishwasher in the flooded area of the washing or cleaning room, preferably outside the washing drum in a drum washing machine. The device can be a permanently installed component of the washing machine or dishwasher or a separate component. In a further embodiment of the invention, the electrolysis device, which is designed in particular as an electrolysis cell, is designed as a separate device that is separate from a washing machine or dishwasher and is operated with its own power source, for example a battery (e-bleach ball). A further embodiment according to the invention consists in integrating the electrolysis device into an additional water circuit within the machine. In all embodiments, it is important that the electrodes of the electrolysis device can come into contact with the electrolyte (the washing or cleaning liquor, or the service water supplied), which contains the organic mediator compound, for example if the e-bleach ball moves during the Washing process is in the washing drum of a washing machine.

It is particularly advantageous that the activity of the bleach can be easily modified by controlling the current strength, if desired as a function of the degree of soiling or the fabric. In textile washing processes, there is no damage to the textile treated in this way that goes beyond the extent that occurs when using commercially available agents.

Within the scope of the method according to the invention, it is preferred if the concentration of the mediator compound in the aqueous washing or cleaning liquor is 0.05 mmol/l to 5 mmol/l, in particular 0.1 mmol/l to 2 mmol/l. The process according to the invention is preferably carried out at temperatures in the range from 10.degree. C. to 95.degree. C., in particular from 20.degree. C. to 40.degree. The process according to the invention is preferably carried out at pH values in the range from pH 2 to pH 12, in particular from pH 4 to pH 11.

The method according to the invention can be implemented in a particularly simple manner by using a washing or cleaning agent which contains the mediator compound. Detergents for cleaning textiles and detergents for cleaning hard surfaces, in particular dishwashing detergents and among these preferably those for machine use, which contain 0.1% by weight to 10% by weight of an organic mediator compound which is produced by electrolysis by a redox reaction can be converted into a bleaching-active species and in the production of the bleaching-active species releases an electron, in addition to customary ingredients compatible therewith, in particular a surfactant, are therefore further subjects of the invention. Although the success according to the invention is already achieved through the electrolytic generation of the bleaching-active species, a composition used according to the invention can additionally also contain, in particular, peroxygen-containing bleaching agents. A particular advantage, however, is that both bleaching agents and conventional bleaching activators can be dispensed with, with the result that a smaller amount of washing or cleaning agent has to be used per washing or cleaning cycle. In a preferred embodiment, an agent used according to the invention is therefore free of bleach and conventional bleach activator.

Agents used according to the invention preferably contain 0.5% by weight to 5% by weight of the mediator compound. The above-mentioned regulation of the bleaching activity via the amperage can be used to carry out a bleaching and a bleach-free application using the same agent if the amperage is regulated down to 0 for the latter case. The consumer therefore only needs a single detergent to wash non-sensitive, generally white, and sensitive, generally colored textiles.

The agents used according to the invention, which can be in the form of, in particular, powdered solids, in post-compacted particle form, as homogeneous solutions or suspensions, can in principle contain all known ingredients that are customary in such agents, in addition to the mediator compound. The agents used according to the invention can in particular builder substances, surface-active surfactants, water-miscible organic solvents, enzymes, sequestering agents, electrolytes, pH regulators, polymers with special effects, such as soil release polymers, color transfer inhibitors, graying inhibitors, wrinkle-reducing polymeric active ingredients and shape-retaining polymeric active ingredients, bleaching agents, bleaching boosters , and other auxiliaries such as optical brighteners, foam regulators, colors and fragrances.

The agents used according to the invention can contain one or more surfactants, with anionic surfactants, nonionic surfactants and mixtures thereof being particularly suitable, but cationic and/or amphoteric surfactants can also be present. Suitable nonionic surfactants are, in particular, alkyl glycosides and ethoxylation and/or propoxylation products of alkyl glycosides or linear or branched alcohols each having 12 to 18 carbon atoms in the alkyl moiety and 3 to 20, preferably 4 to 10, alkyl ether groups. Corresponding ethoxylation and/or propoxylation products of N-alkylamines, vicinal diols, fatty acid esters and fatty acid amides which correspond to the long-chain alcohol derivatives mentioned with regard to the alkyl moiety, and of alkylphenols having 5 to 12 carbon atoms in the alkyl radical can also be used.

Suitable anionic surfactants are, in particular, soaps and those which contain sulfate or sulfonate groups with preferably alkali metal ions as cations. Soaps that can be used are preferably the alkali metal salts of saturated or unsaturated fatty acids having 12 to 18 carbon atoms. Such fatty acids can also be used in a form that is not completely neutralized. The usable surfactants of the sulfate type include the salts of the sulfuric acid half esters of fatty alcohols having 12 to 18 carbon atoms and the sulfation products of said nonionic surfactants with a low degree of ethoxylation. The surfactants of the sulfonate type that can be used include linear alkyl benzene sulfonates having 9 to 14 carbon atoms in the alkyl moiety, alkane sulfonates having 12 to 18 carbon atoms, and olefin sulfonates having 12 to 18 carbon atoms, which are formed in the reaction of corresponding monoolefins with sulfur trioxide, and alpha-sulfofatty acid esters resulting from the sulfonation of fatty acid methyl or ethyl esters.

Such surfactants are contained in the cleaning or washing agents used according to the invention in proportions of preferably 5% by weight to 50% by weight, in particular from 8% by weight to 30% by weight, while the disinfectants used according to the invention as well cleaning agents used according to the invention preferably contain 0.1% by weight to 20% by weight, in particular 0.2% by weight to 5% by weight, of surfactants.

worin jede Gruppe R¹ unabhängig voneinander ausgewählt ist aus C_1-6-Alkyl-,-Alkenyl- oder -Hydroxyalkylgruppen; jede Gruppe R² unabhängig voneinander ausgewählt ist aus C_8-28-Alkyl- oder -Alkenylgruppen; R³ = R¹ oder (CH₂)_n-T-R²; R⁴ = R¹ oder R² oder (CH₂)_n-T-R²; T = -CH₂-, -O-CO- oder -CO-O- und n eine ganze Zahl von 0 bis 5 ist. Die kationischen Tenside weisen übliche Anionen in zum Ladungsausgleich notwendiger Art und Anzahl auf, wobei diese neben beispielsweise Halogeniden auch aus den anionischen Tensiden ausgewählt werden können. In bevorzugten Ausführungsformen der vorliegenden Erfindung kommen als kationische Tenside Hydroxyalkyltrialkyl-ammonium-verbindungen, insbesondere C₁₂-₁₈-Alkyl(hydroxyethyl)dimethylammoniumverbindungen, und vorzugsweise deren Halogenide, insbesondere Chloride, zum Einsatz. Ein erfindungsgemäß eingesetztes Mittel enthält vorzugsweise 0,5 Gew.-% bis 25 Gew.-%, insbesondere 1 Gew.-% bis 15 Gew.-% kationisches Tensid.The agents used according to the invention, especially when they are those intended for the treatment of textiles, can contain, in particular, one or more of the cationic, fabric-softening substances as cationic active substances with a fabric-softening effect general formulas X, XI or XII contain:

wherein each R ¹ group is independently selected from C _1-6 alkyl, alkenyl or hydroxyalkyl groups; each R ² group is independently selected from C _8-28 alkyl or alkenyl groups; R ³ = R ¹ or (CH ₂ ) _n -TR ² ; R ⁴ = R ¹ or R ² or (CH ₂ ) _n -TR ² ; T = -CH ₂ -, -O-CO- or -CO-O- and n is an integer from 0 to 5. The cationic surfactants have the usual anions in the type and number necessary for charge equalization, and these can also be selected from the anionic surfactants in addition to, for example, halides. In preferred embodiments of the present invention, hydroxyalkyltrialkylammonium compounds, in particular _C.sub.12-18 - _alkyl (hydroxyethyl)dimethylammonium compounds, and preferably their halides, in particular chlorides, are used as cationic surfactants. A composition used according to the invention preferably contains 0.5% by weight to 25% by weight, in particular 1% by weight to 15% by weight, of cationic surfactant.

A composition used according to the invention preferably contains at least one water-soluble and/or water-insoluble, organic and/or inorganic builder. The water-soluble organic builder substances include polycarboxylic acids, especially citric acid and sugar acids, monomeric and polymeric aminopolycarboxylic acids, especially methylglycinediacetic acid, nitrilotriacetic acid and ethylenediaminetetraacetic acid, as well as polyaspartic acid, polyphosphonic acids, especially aminotris(methylenephosphonic acid), ethylenediaminetetrakis(methylenephosphonic acid) and 1-hydroxyethane-1,1- diphosphonic acid, polymeric hydroxy compounds such as dextrin and polymeric (poly)carboxylic acids, in particular polycarboxylates accessible by oxidation of polysaccharides or dextrins, and/or polymeric acrylic acids, methacrylic acids, maleic acids and copolymers of these, which can also contain small amounts of polymerizable substances without carboxylic acid functionality in polymerized form. The relative molecular mass of the homopolymers of unsaturated carboxylic acids is generally between 5,000 and 200,000, and that of the copolymers between 2,000 and 200,000, preferably 50,000 to 120,000, in each case based on the free acid. A particularly preferred acrylic acid-maleic acid copolymer has a molecular weight of 50,000 to 100,000. Suitable, albeit less preferred, compounds of this class are copolymers of acrylic acid or methacrylic acid with vinyl ethers, such as vinyl methyl ethers, vinyl esters, ethylene, propylene and styrene in which the proportion of the acid is at least 50% by weight. Terpolymers which contain two unsaturated acids and/or their salts as monomers and vinyl alcohol and/or an esterified vinyl alcohol or a carbohydrate as the third monomer can also be used as water-soluble organic builder substances. The first acidic monomer or its salt is derived from a monoethylenically unsaturated C ₃ -C ₈ -carboxylic acid and preferably from a C ₃ -C ₄ -monocarboxylic acid, in particular from (meth)acrylic acid. The second acidic monomer or its salt can be a derivative of a C ₄ -C ₈ -dicarboxylic acid, maleic acid being particularly preferred, and/or a derivative of an allylsulfonic acid which is substituted in the 2-position with an alkyl or aryl radical. Such polymers generally have a molecular weight between 1,000 and 200,000. Further preferred copolymers are those which contain acrolein and acrylic acid/acrylic acid salts or vinyl acetate as monomers. The organic builder substances can be used in the form of aqueous solutions, preferably in the form of 30 to 50 percent by weight aqueous solutions, particularly for the production of liquid compositions. All of the acids mentioned are generally used in the form of their water-soluble salts, in particular their alkali metal salts.

Such organic builder substances can, if desired, be present in amounts of up to 40% by weight, in particular up to 25% by weight and preferably from 1% by weight to 8% by weight. Amounts close to the upper limit mentioned are preferably used in pasty or liquid, in particular aqueous, compositions used according to the invention.

Particularly suitable as water-soluble inorganic builder materials are polymeric alkali metal phosphates, which can be present in the form of their alkaline, neutral or acidic sodium or potassium salts. Examples of these are tetrasodium diphosphate, disodium dihydrogen diphosphate, pentasodium triphosphate, so-called sodium hexametaphosphate and the corresponding potassium salts or mixtures of sodium and potassium salts. In particular, crystalline or amorphous alkali metal aluminosilicates, in amounts of up to 50% by weight, preferably not more than 40% by weight and in liquid compositions, in particular from 1% by weight to 5% by weight, are used as water-insoluble, water-dispersible inorganic builder materials. deployed. Among these, the crystalline detergent grade sodium aluminosilicates, particularly zeolite A, P and optionally X, are preferred. Amounts close to the upper limit mentioned are preferably used in solid, particulate compositions. In particular, suitable aluminosilicates do not have any particles with a particle size of more than 30 μm and preferably consist of at least 80% by weight of particles with a size of less than 10 μm. Your calcium binding capacity, according to the information in the German patent specification DE 24 12 837 can be determined is usually in the range of 100 to 200 mg CaO per gram.

Suitable substitutes or partial substitutes for the aluminosilicate mentioned are crystalline alkali metal silicates, which can be present alone or in a mixture with amorphous silicates. The alkali metal silicates which can be used as builders in the detergents used according to the invention preferably have a molar ratio of alkali metal oxide to SiO ₂ below 0.95, in particular from 1:1.1 to 1:12, and can be present in amorphous or crystalline form. Preferred alkali metal silicates are the sodium silicates, in particular the amorphous sodium silicates, with a molar ratio Na ₂ O:SiO ₂ from 1:2 to 1:2.8. Crystalline phyllosilicates of the general formula Na ₂ Si _x O _2x+1 y H ₂ O are preferably used as crystalline silicates, which can be present alone or in a mixture with amorphous silicates, in which x, the so-called modulus, is a number from 1, 9 to 4 and y is a number from 0 to 20 and preferred values for x are 2, 3 or 4. Preferred crystalline layered silicates are those in which x has the value 2 or 3 in the general formula mentioned. In particular, both β- and δ-sodium dinitrates (Na ₂ Si ₂ O ₅ .yH ₂ O) are preferred. Practically anhydrous crystalline alkali metal silicates of the abovementioned general formula, in which x is a number from 1.9 to 2.1, produced from amorphous alkali metal silicates can also be used in agents used according to the invention. In a further preferred embodiment of agents used according to the invention, a crystalline sodium sheet silicate with a modulus of 2 to 3 is used, as can be produced from sand and soda. Crystalline sodium silicates with a modulus in the range from 1.9 to 3.5 are used in a further preferred embodiment of agents used according to the invention. In a preferred embodiment of agents used according to the invention, a granular compound of alkali metal silicate and alkali metal carbonate is used, as is commercially available, for example, under the name ^Nabion® 15. If alkali metal aluminosilicate, in particular zeolite, is also present as an additional builder substance, the weight ratio of aluminosilicate to silicate, based in each case on anhydrous active substances, is preferably 1:10 to 10:1. In compositions containing both amorphous and crystalline alkali metal silicates, the weight ratio of amorphous alkali metal silicate to crystalline alkali metal silicate is preferably 1:2 to 2:1 and in particular 1:1 to 2:1.

The detergents or cleaning agents used according to the invention preferably contain builder substances in amounts of up to 60% by weight, in particular from 5% by weight to 40% by weight.

1. a) 5 Gew.-% bis 35 Gew.-% Citronensäure, Alkalicitrat und/oder Alkalicarbonat, welches auch zumindest anteilig durch Alkalihydrogencarbonat ersetzt sein kann,
2. b) bis zu 10 Gew.-% Alkalisilikat mit einem Modul im Bereich von 1,8 bis 2,5,
3. c) bis zu 2 Gew.-% Phosphonsäure und/oder Alkaliphosphonat,
4. d) bis zu 50 Gew.-% Alkaliphosphat, und
5. e) bis zu 10 Gew.-% polymerem Polycarboxylat,

wobei die Mengenangaben sich auf das gesamte Wasch- beziehungsweise Reinigungsmittel beziehen. Dies gilt auch für alle folgenden Mengenangaben, sofern nicht ausdrücklich anders angegeben.In a preferred embodiment of the invention, an agent used according to the invention has a water-soluble builder block. The use of the term "builder block" is intended to express that the agent does not contain any other builder substances than those that are water-soluble, i.e. all the builder substances contained in the agent are combined in the "block" characterized in this way, with at most the amounts of Substances are excluded, which may be commercially available as impurities or stabilizing additives in small amounts in the other ingredients of the agent. The term “water-soluble” should be understood to mean that the builder block dissolves without residue at the concentration that results from the amount of agent containing it under the usual conditions. The compositions used according to the invention preferably contain at least 15% by weight and up to 55% by weight, in particular 25% by weight to 50% by weight, of water-soluble builder block. This is preferably composed of the components

1. a) 5% by weight to 35% by weight of citric acid, alkali metal citrate and/or alkali metal carbonate, which can also be replaced at least partially by alkali metal bicarbonate,
2. b) up to 10% by weight of alkali silicate with a modulus in the range from 1.8 to 2.5,
3. c) up to 2% by weight of phosphonic acid and/or alkali metal phosphonate,
4. d) up to 50% by weight alkali metal phosphate, and
5. e) up to 10% by weight polymeric polycarboxylate,

where the quantities are based on the total detergent or cleaning agent. This also applies to all the following quantities, unless expressly stated otherwise.

In a preferred embodiment of agents used according to the invention, the water-soluble builder block contains at least 2 of components b), c), d) and e) in amounts greater than 0% by weight.

With regard to component a), in a preferred embodiment of agents used according to the invention, 15% by weight to 25% by weight alkali metal carbonate, which can be replaced at least partially by alkali metal hydrogen carbonate, and up to 5% by weight, in particular 0.5% by weight -% to 2.5% by weight of citric acid and/or alkali citrate. In an alternative embodiment of agents used according to the invention, as component a) 5% by weight to 25% by weight, in particular 5% by weight to 15% by weight, of citric acid and/or alkali metal citrate and up to 5% by weight in particular 1% by weight to 5% by weight of alkali metal carbonate, at least some of which can be replaced by alkali metal bicarbonate. If both alkali metal carbonate and alkali metal bicarbonate are present, component a) preferably has alkali metal carbonate and alkali metal bicarbonate in a weight ratio of from 10:1 to 1:1.

With regard to component b), a preferred embodiment of agents used according to the invention contains 1% by weight to 5% by weight of alkali metal silicate with a modulus in the range from 1.8 to 2.5.

With regard to component c), a preferred embodiment of agents used according to the invention contains 0.05% by weight to 1% by weight of phosphonic acid and/or alkali metal phosphonate. Phosphonic acids are also understood as meaning optionally substituted alkyl phosphonic acids which can also have several phosphonic acid groups (so-called polyphosphonic acids). They are preferably selected from the hydroxy and/or aminoalkylphosphonic acids and/or their alkali metal salts, such as dimethylaminomethanediphosphonic acid, 3-aminopropane-1-hydroxy-1,1-diphosphonic acid, 1-amino-1-phenylmethanediphosphonic acid, 1-hydroxyethane -1,1-diphosphonic acid, amino-tris(methylenephosphonic acid), N,N,N',N'-ethylenediaminetetrakis(methylenephosphonic acid) and acylated derivatives of phosphorous acid, which can also be used in any mixtures.

With regard to component d), a preferred embodiment of agents used according to the invention contains 15% by weight to 35% by weight of alkali metal phosphate, in particular trisodium polyphosphate. Alkaline phosphate is the general term for the alkali metal (especially sodium and potassium) salts of the various phosphoric acids, in which metaphosphoric acids (HPO ₃ ) _n and orthophosphoric acid H ₃ PO ₄ can be distinguished in addition to higher-molecular representatives. The phosphates combine several advantages: they act as alkali carriers, prevent lime deposits on machine parts and lime incrustations in fabrics and also contribute to the cleaning performance. Sodium dihydrogen phosphate, NaH ₂ PO ₄ , exists as a dihydrate (density 1.91 gcm ^-3 , melting point 60°) and as a monohydrate (density 2.04 gcm ^-3 ). Both salts are white powders, very easily soluble in water, which lose the water of crystallization when heated and are converted into the weakly acidic diphosphate (disodium hydrogen diphosphate, Na ₂ H ₂ P ₂ O ₇ ) at 200°C and into sodium trimetaphosphate (Na ₃ P ₃ O ₉ ) and Madrell's salt. NaH ₂ PO ₄ is acidic; it is formed when phosphoric acid is adjusted to a pH value of 4.5 with sodium hydroxide solution and the mash is sprayed. Potassium dihydrogen phosphate (potassium phosphate primary or monobasic, potassium biphosphate, KDP), KH ₂ PO ₄ , is a white salt with a density of 2.33 gcm ^-3 , a melting point of 253° (decomposes to form (KPO ₃ ) _x , potassium polyphosphate) and is easily soluble in water. Disodium hydrogen phosphate (secondary sodium phosphate), Na ₂ HPO ₄ , is a colourless, very easily water-soluble crystalline salt. It exists anhydrous and with 2 mol. (density 2.066 gcm ^-3 , loss of water at 95°), 7 mol. (density 1.68 gcm ^-3 , melting point 48° with loss of 5 H ₂ O) and 12 mol. water ( Density 1.52 gcm- ³ , melting point 35° with loss of 5 H ₂ O), becomes anhydrous at 100° and turns into the diphosphate Na ₄ P ₂ O ₇ when heated more intensely. Disodium hydrogen phosphate is produced by neutralizing phosphoric acid with soda solution using phenolphthalein as an indicator. Dipotassium hydrogen phosphate (secondary or dibasic potassium phosphate), K ₂ HPO ₄ , is an amorphous, white salt that is easily soluble in water. Trisodium phosphate, tertiary sodium phosphate, Na ₃ PO ₄ , are colorless crystals which, as dodecahydrate, have a density of 1.62 gcm ^-3 and a melting point of 73-76°C (decomposition), as decahydrate (equivalent to 19-20% P ₂ O ₅ ) have a melting point of 100°C and in anhydrous form (corresponding to 39-40% P ₂ O ₅ ) a density of 2.536 gcm ^-3 . Trisodium phosphate is easily soluble in water with an alkaline reaction and is prepared by evaporating a solution of exactly 1 mole of disodium phosphate and 1 mole of NaOH. Tripotassium phosphate (potassium tertiary or tribasic phosphate), K ₃ PO ₄ , is a white, deliquescent, granular powder with a density of 2.56 gcm ^-3 , has a melting point of 1340° and is readily soluble in water with an alkaline reaction. It is formed, for example, when Thomas slag is heated with coal and potassium sulphate. Despite the higher price, the more easily soluble and therefore highly effective potassium phosphates are often preferred to the corresponding sodium compounds in the cleaning agent industry. Tetrasodium diphosphate (sodium pyrophosphate), Na ₄ P ₂ O ₇ , exists in anhydrous form (density 2.534 gcm ^-3 , melting point 988°, also given as 880°) and as decahydrate (density 1.815-1.836 gcm ^-3 , melting point 94° with loss of water) . Substances are colorless crystals that are soluble in water with an alkaline reaction. Na ₄ P ₂ O ₇ is formed when disodium phosphate is heated to >200°C or by reacting phosphoric acid with soda in a stoichiometric ratio and dewatering the solution by spraying. The decahydrate complexes heavy metal salts and hardeners and therefore reduces the hardness of the water. Potassium diphosphate (potassium pyrophosphate), K ₄ P ₂ O ₇ , exists in the form of the trihydrate and is a colourless, hygroscopic powder with a density of 2.33 gcm ^-3 , which is soluble in water at a pH of 1% solution at 25° is 10.4. Condensation of the NaH ₂ PO ₄ or the KH ₂ PO ₄ results in higher mol. Sodium and potassium phosphates, in which one can distinguish between cyclic representatives, the sodium or potassium metaphosphates, and chain-type types, the sodium or potassium polyphosphates. A large number of terms are used for the latter in particular: melted or calcined phosphates, Graham's salt, Kurrol's and Madrell's salt. All higher sodium and potassium phosphates are collectively referred to as condensed phosphates. That technically important pentasodium triphosphate, Na ₅ P ₃ O ₁₀ (sodium tripolyphosphate), is an anhydrous or crystallizing with 6 H ₂ O, non-hygroscopic, white, water-soluble salt of the general formula NaO-[P(O)(ONa)-O] _n - Well with n=3. In 100 g water, about 17 g dissolve at room temperature, about 20 g at 60°, and about 32 g at 100° of the anhydrous salt; After heating the solution for two hours at 100°, about 8% orthophosphate and 15% diphosphate are formed by hydrolysis. In the production of pentasodium triphosphate, phosphoric acid is reacted with soda solution or caustic soda in a stoichiometric ratio and the solution is dewatered by spraying. Similar to Graham's salt and sodium diphosphate, pentasodium triphosphate dissolves many insoluble metal compounds (including soap scum). Pentapotassium triphosphate, K ₅ P ₃ O ₁₀ (potassium tripolyphosphate), is commercially available, for example, in the form of a 50% by weight solution (>23% P ₂ O ₅ , 25% K ₂ O). Potassium polyphosphates are widely used in the detergent and cleaning agent industry. There are also sodium potassium tripolyphosphates which can also be used within the scope of the present invention. These arise, for example, when sodium trimetaphosphate is hydrolyzed with KOH:

(NaPO ₃ ) ₃ + 2 KOH → Na ₃ K ₂ P ₃ O ₁₀ + H ₂ O

These can be used just like sodium tripolyphosphate, potassium tripolyphosphate or mixtures of these two; Mixtures of sodium tripolyphosphate and sodium potassium tripolyphosphate or mixtures of potassium tripolyphosphate and sodium potassium tripolyphosphate or mixtures of sodium tripolyphosphate and potassium tripolyphosphate and sodium potassium tripolyphosphate can also be used.

With regard to component e), a preferred embodiment of agents used according to the invention contains 1.5% by weight to 5% by weight of polymeric polycarboxylate, in particular selected from the polymerization or copolymerization products of acrylic acid, methacrylic acid and/or maleic acid. Among these, the homopolymers of acrylic acid and among these, in turn, those with an average molar mass in the range from 5,000 D to 15,000 D (PA standard) are particularly preferred.

In addition to the oxidases mentioned below, suitable enzymes in the agents are those from the class of proteases, lipases, cutinases, amylases, pullulanases, mannanases, cellulases, hemicellulases, xylanases and peroxidases and mixtures thereof, for example proteases such as ^BLAP® , ^Optimase® , Opticlean ^® , Maxacal ^® , Maxapem ^® , Alcalase ^® , Esperase ^® , Savinase ^® , Durazym ^® and/or Purafect ^® OxP, amylases such as Termamyl ^® , Amylase-LT ^® , Maxamyl ^® , Duramyl ^® and/or Purafect ^® OxAm, lipases such as Lipolase ^® , Lipomax ^® , Lumafast ^® and/or Lipozym ^® , cellulases such as Celluzyme ^® and/or Carezyme ^® . Enzymatic active substances obtained from fungi or bacteria such as Bacillus subtilis, Bacillus licheniformis, Streptomyces griseus, Humicola lanuginosa, Humicola insolens, Pseudomonas pseudoalcaligenes or Pseudomonas cepacia are particularly suitable. Any enzymes used can be adsorbed on carriers and/or embedded in encapsulating substances in order to protect them against premature inactivation. They are in the detergents used according to the invention, Cleaning agents and disinfectants preferably in amounts of up to 10% by weight, in particular from 0.2% by weight to 2% by weight, with enzymes stabilized against oxidative degradation being particularly preferably used.

In a preferred embodiment of the invention, the agent contains 5% by weight to 50% by weight, in particular 8-30% by weight, of anionic and/or nonionic surfactant, up to 60% by weight, in particular 5-40% by weight. -% builder substance and 0.2% to 2% by weight of enzyme selected from the proteases, lipases, cutinases, amylases, pullulanases, mannanases, cellulases, oxidases and peroxidases and mixtures thereof.

Peroxygen compounds which may be present in the agents, but which can preferably be omitted in agents intended for use in the process according to the invention, include in particular organic peracids or peracid salts of organic acids, such as phthalimidopercaproic acid, perbenzoic acid or salts of diperdodecanedioic acid, hydrogen peroxide and inorganic substances which release hydrogen peroxide under the washing conditions Salts such as perborate, percarbonate and/or persilicate. Hydrogen peroxide can also be generated with the help of an enzymatic system, ie an oxidase and its substrate. If solid peroxygen compounds are to be used, they can be used in the form of powders or granules, which can also be coated in a manner known in principle. Alkali metal percarbonate, alkali metal perborate monohydrate, alkali metal perborate tetrahydrate or hydrogen peroxide in the form of aqueous solutions containing 3% by weight to 10% by weight of hydrogen peroxide is particularly preferably used. If desired, peroxygen compounds are present in amounts of up to 50% by weight, in particular from 5% by weight to 30% by weight, in detergents or cleaning agents used according to the invention.

In addition, customary bleach activators, which form peroxocarboxylic acids or peroxoimidic acids under perhydrolysis conditions, and/or customary bleach-activating transition metal complexes can be used. The component of the bleach activators which is optionally present, in particular in amounts of from 0.5% by weight to 6% by weight, comprises the N- or O-acyl compounds which are customarily used, for example polyacylated alkylenediamines, in particular tetraacetylethylenediamine, acylated glycolurils, in particular tetraacetylglycoluril, N-acylated hydantoins, hydrazides, triazoles, urazoles, diketopiperazines, sulfurylamides and cyanurates, also carboxylic acid anhydrides, especially phthalic anhydride, carboxylic acid esters, especially sodium isononanoyl phenolsulfonate, and acylated sugar derivatives, especially pentaacetyl glucose, and cationic nitrile derivatives such as trimethylammonium acetonitrile salts. To avoid interaction with the per-compounds during storage, the bleach activators may have been coated or granulated in a known manner with encapsulating substances, granulated tetraacetylethylenediamine having an average grain size of 0.01 mm to 0.8 mm, granulated 1,5- Diacetyl-2,4-dioxohexahydro-1,3,5-triazine, and/or trialkylammoniumacetonitrile formulated in particulate form is particularly preferred. Such bleach activators are preferably present in detergents or cleaning agents in amounts of up to 8% by weight, in particular from 2% by weight to 6% by weight, in each case based on the detergent as a whole.

The organic solvents that can be used in the agents used according to the invention, especially if they are in liquid or pasty form, include alcohols with 1 to 4 carbon atoms, in particular methanol, ethanol, isopropanol and tert-butanol, diols with 2 to 4 carbon atoms Atoms, in particular ethylene glycol and propylene glycol, and mixtures thereof and the ethers which can be derived from the classes of compounds mentioned. Such water-miscible solvents are preferably present in the detergents used according to the invention in not more than 30% by weight, in particular from 6% by weight to 20% by weight.

To set a desired pH value that does not result automatically from mixing the other components, the agents used according to the invention can contain acids that are compatible with the system and the environment, in particular citric acid, acetic acid, tartaric acid, malic acid, lactic acid, glycolic acid, succinic acid, glutaric acid and/or adipic acid , but also contain mineral acids, in particular sulfuric acid, or bases, in particular ammonium or alkali metal hydroxides. The compositions used according to the invention preferably contain no more than 20% by weight of such pH regulators, in particular from 1.2% by weight to 17% by weight.

Polymers capable of releasing dirt, which are often referred to as "soil release" active substances or as "soil repellents" because of their ability to make the treated surface, for example the fiber, dirt-repellent, are, for example, nonionic or cationic cellulose derivatives. The particularly polyester-active soil release polymers include copolyesters of dicarboxylic acids, for example adipic acid, phthalic acid or terephthalic acid, diols, for example ethylene glycol or propylene glycol, and polydiols, for example polyethylene glycol or polypropylene glycol. The preferably used dirt-removing polyesters include those compounds that are formally accessible by esterification of two monomer parts, the first monomer being a dicarboxylic acid HOOC-Ph-COOH and the second monomer being a diol HO-(CHR ¹¹ -) _a OH, which can also be used as a polymeric diol H-(O-(CHR ¹¹ -) _a ) _b OH may be present. Ph is an o-, m- or p-phenylene radical which can carry 1 to 4 substituents selected from alkyl radicals having 1 to 22 carbon atoms, sulfonic acid groups, carboxyl groups and mixtures thereof, R ¹¹ is hydrogen, an alkyl radical having 1 to 22 carbon atoms and mixtures thereof, a is a number from 2 to 6 and b is a number from 1 to 300. The polyesters obtainable from these preferably contain both monomer diol units -O-(CHR ¹¹ -) _a O- and polymer diol units --( O-(CHR ¹¹ -) _a ) _b O- before. The molar ratio of monomer diol units to polymer diol units is preferably 100:1 to 1:100, in particular 10:1 to 1:10. The degree of polymerization b in the polymer diol units is preferably in the range from 4 to 200, in particular from 12 to 140. The molecular weight or the average molecular weight or the maximum of the molecular weight distribution of preferred soil-removing polyesters is in the range from 250 to 100,000, in particular from 500 to 50,000 The acid on which the radical Ph is based is preferably selected from terephthalic acid, isophthalic acid, phthalic acid, trimellitic acid, mellitic acid, the isomers of sulfophthalic acid, sulfoisophthalic acid and sulfoterephthalic acid and mixtures thereof. If their acid groups are not part of the ester bonds in the polymer, they are preferably present in salt form, in particular as an alkali metal or ammonium salt. Under of these, the sodium and potassium salts are particularly preferred. If desired, instead of the HOOC-Ph-COOH monomer, small proportions, in particular not more than 10 mol % based on the proportion of Ph with the meaning given above, of other acids which have at least two carboxyl groups can be present in the soil-removing polyester. These include, for example, alkylene and alkenylenedicarboxylic acids such as malonic acid, succinic acid, fumaric acid, maleic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid. Examples of diol components are ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,2-decanediol, 1, 2-dodecanediol and neopentyl glycol. Particularly preferred among the polymeric diols is polyethylene glycol with an average molar mass in the range from 1000 to 6000. If desired, these polyesters can also be end-capped, suitable end groups being alkyl groups having 1 to 22 carbon atoms and esters of monocarboxylic acids. Polymers of ethylene terephthalate and polyethylene oxide terephthalate, in which the polyethylene glycol units have a molecular weight of 750 to 5000 and the molar ratio of ethylene terephthalate to polyethylene oxide terephthalate is 50:50 to 90:10, are preferably used alone or in combination with cellulose derivatives.

The dye transfer inhibitors suitable for use in detergents used according to the invention for washing textiles include, in particular, polyvinylpyrrolidones, polyvinylimidazoles, polymeric N-oxides such as poly(vinylpyridine-N-oxide) and copolymers of vinylpyrrolidone with vinylimidazole and optionally other monomers.

The detergents used according to the invention for use in textile washing can contain anti-crease agents, since textile fabrics, in particular made of rayon, wool, cotton and mixtures thereof, can tend to wrinkle because the individual fibers are sensitive to bending, kinking, pressing and squeezing transversely to the fiber direction. These include, for example, synthetic products based on fatty acids, fatty acid esters, fatty acid amides, fatty acid alkylol esters, fatty acid alkylolamides or fatty alcohols, which are usually reacted with ethylene oxide, or products based on lecithin or modified phosphoric acid esters.

Graying inhibitors have the task of keeping the dirt detached from the hard surface and in particular from the textile fibers suspended in the liquor. Water-soluble colloids, usually of an organic nature, are suitable for this purpose, for example starch, glue, gelatin, salts of ether carboxylic acids or ether sulfonic acids of starch or cellulose or salts of acidic sulfuric acid esters of cellulose or starch. Water-soluble polyamides containing acidic groups are also suitable for this purpose. Furthermore, starch derivatives other than those mentioned above can be used, for example aldehyde starches. Cellulose ethers such as carboxymethyl cellulose (Na salt), methyl cellulose, hydroxyalkyl cellulose and mixed ethers such as methyl hydroxyethyl cellulose, methyl hydroxypropyl cellulose, methyl carboxymethyl cellulose and mixtures thereof are preferably used, for example in amounts of 0.1 to 5% by weight, based on the detergent.

The agents can contain optical brighteners, including, in particular, derivatives of diaminostilbene disulfonic acid or their alkali metal salts. Suitable are, for example, salts of 4,4'-bis (2-anilino-4-morpholino-1,3,5-triazinyl-6-amino) stilbene-2,2'-disulfonic acid or similarly constructed compounds that instead of morpholino - carry a diethanolamino group, a methylamino group, an anilino group or a 2-methoxyethylamino group. Furthermore, brighteners of the substituted diphenylstyryl type may be present, for example the alkali metal salts of 4,4'-bis(2-sulfostyryl)diphenyl, 4,4'-bis(4-chloro-3-sulfostyryl)diphenyl, or 4 -(4-Chlorostyryl)-4'-(2-sulfostyryl)-diphenyls. Mixtures of the aforementioned optical brighteners can also be used.

In particular when used in machine washing or cleaning processes, it can be advantageous to add customary foam inhibitors to the detergents. Examples of suitable foam inhibitors are soaps of natural or synthetic origin which have a high proportion of C ₁₈ -C ₂₄ fatty acids. Examples of suitable non-surfactant foam inhibitors are organopolysiloxanes and mixtures thereof with microfine, optionally silanated silica, and paraffins, waxes, microcrystalline waxes and mixtures thereof with silanated silica or bis-fatty acid alkylenediamides. Mixtures of different foam inhibitors are also used with advantage, for example those made of silicones, paraffins or waxes. The foam inhibitors, in particular silicone- and/or paraffin-containing foam inhibitors, are preferably bound to a granular, water-soluble or water-dispersible carrier substance. Mixtures of paraffins and bistearylethylenediamide are particularly preferred.

Agents used according to the invention can also contain active ingredients to prevent objects made of silver from tarnishing, so-called silver corrosion inhibitors. Preferred silver corrosion inhibitors are organic disulfides, dihydric phenols, trihydric phenols, optionally alkyl- or aminoalkyl-substituted triazoles such as benzotriazole, and cobalt, manganese, titanium, zirconium, hafnium, vanadium or cerium salts and/or complexes in which the Metals are present in one of the oxidation states II, III, IV, V or VI.

The production of solid agents used according to the invention presents no difficulties and can be carried out in a manner known in principle, for example by spray drying or granulation. For the production of agents used according to the invention with an increased bulk density, in particular in the range from 650 g/l to 950 g/l, a process having an extrusion step is preferred. Detergents, cleaning agents or disinfectants in the form of aqueous solutions or solutions containing other customary solvents are particularly advantageously produced by simply mixing the ingredients, which can be added to an automatic mixer as such or as a solution. In a preferred embodiment of agents for cleaning dishes, in particular in a machine, these are in the form of tablets.

example

A 2 millimolar aqueous solution of violuric acid made up with acetate buffer pH 4.5 was activated at room temperature with a potential difference of 1.35 V (Ag/AgCl) using a graphite working electrode and a 15 Coulomb stainless steel counter electrode. Cotton substrates which had been provided with standardized tea stains or a standardized blueberry juice stain were then treated in the solution at 40° C. for 60 minutes. The tissues showed a clear brightening.

Claims (6)

1. Method for washing textiles or for cleaning hard surfaces, in particular for machine cleaning of dishes, using a bleach-active species generated electrolytically by a redox reaction from an organic mediator compound, characterized in that the mediator compound emits an electron during the preparation of the active bleach species, the organic mediator compound being an aliphatic, cycloaliphatic, aromatic or araliphatic compound optionally containing heteroatoms, which compound comprises an N-OH, NOR group, a nitroxyl radical N-O·, and/or an N-O^- group having a counter cation M⁺ or ½ M²⁺, where R is an alkyl group having in particular 1 to 4 C atoms and M is hydrogen, an alkali metal or an alkaline-earth metal, and in particular a hydroxamic acid such as N-hydroxyphthalimide, an N-hydroxy heteroaromatic such as 1-hydroxyindole, 1-hydroxybenzimidazole and 1-hydroxybenzotriazole, a radical of a sterically hindered N-hydroxy compound such as (2,2,6,6-tetramethylpiperidin-1-yl)oxyl and an oximidoketone such as violuric acid and N,N'-dimethyl violuric acid, and liquor containing the mediator compound being electrolyzed continuously or once or multiple times for specific periods of time, in particular 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes.
2. Method for washing textiles or for cleaning hard surfaces, in particular for machine cleaning of dishes, using a bleach-active species generated electrolytically by a redox reaction from an organic mediator compound, characterized in that the mediator compound emits an electron during the preparation of the active bleach species, the organic mediator compound being an aliphatic, cycloaliphatic, aromatic or araliphatic compound optionally containing heteroatoms, which compound comprises an N-OH, NOR group, a nitroxyl radical N-O·, and/or an N-O^- group having a counter cation M⁺ or ½ M²⁺, where R is an alkyl group having in particular 1 to 4 C atoms and M is hydrogen, an alkali metal or an alkaline-earth metal, and in particular a hydroxamic acid such as N-hydroxyphthalimide, an N-hydroxy heteroaromatic such as 1-hydroxyindole, 1-hydroxybenzimidazole and 1-hydroxybenzotriazole, a radical of a sterically hindered N-hydroxy compound such as (2,2,6,6-tetramethylpiperidin-1-yl)oxyl and an oximidoketone such as violuric acid and N,N'-dimethyl violuric acid, the mediator compound, in particular when using a conventional dispensing device, passing through an electrolysis device before entering the chamber of a washing machine, in particular flowing through an electrolysis cell in aqueous solution or suspension.
3. Method according to claim 1 or 2, characterized in that the electrolysis device, which is designed in particular as an electrolysis cell, is designed as a separate device which is separate from a washing machine or dishwasher and is operated by its own power source.
4. Method according to one of claims 1 to 3, characterized in that the concentration of the mediator compound in the aqueous washing or cleaning liquor is 0.05 mmol/L to 5 mmol/L, in particular 0.1 mmol/L to 2 mmol/L.
5. Method according to one of claims 1 to 4, characterized in that it is carried out at pH values in the range of from pH 2 to pH 12, in particular from pH 4 to pH 11.
6. Method according to one of claims 1 to 5, characterized in that the organic mediator compound forms a reversible redox system in aqueous solution.