EP2329000B1 - Use of manganese oxalates as bleach catalysts - Google Patents

Abstract

The invention relates to the use of manganese oxalates in detergents and cleaning agents, in particular in cleaning agents containing peroxy compounds for hard surfaces.

Description

The present invention relates to the use of manganese oxalates in detergents on hard surfaces as bleach catalysts for enhancing the bleaching effect of inorganic peroxygen compounds in bleaching colored stains on hard surfaces.

Inorganic peroxygen compounds, particularly hydrogen peroxide and solid peroxygen compounds which dissolve in water to release hydrogen peroxide, such as sodium perborate and sodium carbonate perhydrate, have long been used as oxidizing agents for disinfecting and bleaching purposes. The oxidation effect of these substances in dilute solutions depends strongly on the temperature; Thus, for example, with H ₂ O ₂ or perborate in alkaline bleaching liquors only at temperatures above about 80 ° C, a sufficiently fast bleaching of soiled textiles. At lower temperatures, the oxidation effect of the inorganic peroxygen compounds can be improved by adding so-called bleach activators, for the numerous proposals, especially from the classes of N- or O-acyl compounds, for example, polyacylated alkylenediamines, especially tetraacetylethylenediamine and acylated glycolurils, such as tetraacetylglycoluril, also carboxylic acid anhydrides , in particular phthalic anhydride, carboxylic acid esters, in particular sodium nonanoyloxybenzenesulfonate, sodium lauroyl-benzenesulfonate or decanoyloxybenzoic acid and acylated sugar derivatives, such as pentaacetylglucose, have become known in the literature. In addition, the recent literature claims a number of nitrile derivatives, in particular cationic nitrile quats, for this purpose. By adding these substances, the bleaching action of aqueous peroxide liquors can be increased so much that even at temperatures around 60 ° C substantially the same effects as with the peroxide solution alone at 95 ° C occur.

In the search for energy-saving washing and bleaching processes in recent years application temperatures well below 60 ° C, especially below 45 ° C down to the cold water temperature in importance.

At these low temperatures, the effect of the previously known activator compounds usually decreases noticeably. There has therefore been no lack of efforts to develop more effective systems for this temperature range, without that to date a convincing success would have been recorded. One starting point for this is the use of transition metal salts and complexes, known as bleach catalysts. The metal complexes, provided that they ensure a good soil removal at all under the conditions of the purification process, are usually characterized by a complex synthesis and the associated high production costs of the complex ligand.

Furthermore, a number of relatively simple manganese compounds are described, which cause a certain bleaching efficiency under washing and cleaning conditions in combination with persalts. These include manganese / EDTA complexes as in EP 0 141 470 or manganese sulfate / picolinic acid mixtures, as in US 3,532,634 or manganese (II) or (III) salts in combination with carbonates ( EP 0 082 563 ), Fatty acids ( US 4,626,373 ), Phosphonates ( EP 0 072 166 ), Hydroxycarboxylic acids ( EP 0 237 111 ) or citric acid or its salts ( EP 0 157 483 ). However, none of the above combinations has significant cleaning performance on stubborn tea stains on hard surfaces. Furthermore, it is known that oxalate ions have a positive effect on manganese-catalyzed epoxidations in the presence of trimethyl-1,4,7-triazacyclononane, ( TH Bennur et al., Journal of Molecular Catalysis A: Chemical 185 (2002) 71-80 ).

It has now been found that the use of manganese oxalates in detergent formulations has advantages over physical mixtures consisting of manganese salts and oxalic acid. These include volume reduction of the bleach catalyst for the same or better Bleaching performance, lower hygroscopicity and associated increased storage stability in the formulations.

The invention relates to the use of manganese oxalates as bleach catalysts in cleaning agents, as defined in claim 1.

Manganese oxalates can be prepared in a manner known per se by reacting manganese salts with oxalic acid in water. Examples include in A. Huizing et al., Mat. Res. Bull. Vol. 12, pp. 605-6166, 1977 and Donkova et al., Thermochimica Acta, Vol. 421, pp. 141-149, 2004 , For the use according to the invention, both the white manganese (II) oxalate dihydrate and the pink manganese (II) oxalate trihydrate are suitable. Although they have only a very low water solubility, these compounds surprisingly show a good bleaching performance in combination with inorganic peroxygen compounds. Due to their poor solubility, they also have over other manganese salts such as manganese (II) sulfate, manganese (II) acetate, manganese (III) acetate or manganese (II) chloride better storage stability in alkaline detergent and cleaner formulations. In comparison with physical mixtures of manganese salts and oxalic acid or salts thereof, the manganese oxalates according to the invention are more volume-effective bleach catalysts, which is advantageous, in particular, when used in machine dishwashing detergent tablets.

In addition to a peracid substance compound, the cleaning agents preferably contain from 0.025 to 2.5% by weight, in particular from 0.05 to 1.5% by weight, of bleach-intensifying manganese oxalates. In a particular embodiment, the manganese oxalates may also be combined with oxalic acid, thereby increasing their water solubility. The manganese oxalate: oxalic acid ratio in this case may correspond to 1: 0 to 1: 5 parts by weight.

Suitable peroxygen compounds are hydrogen peroxide, but in the first place alkali perborate or tetrahydrate and / or alkali metal percarbonate, with sodium being the preferred alkali metal. The use of sodium percarbonate has particular advantages in dishwashing detergents, since it has a particularly favorable effect on the corrosion behavior of glasses. The oxygen-based bleaching agent is therefore preferably an alkali percarbonate, especially sodium percarbonate.

The amounts of peroxygen compounds used are generally chosen so that in the solutions between 10 ppm and 10% active oxygen, preferably between 50 ppm and 5000 ppm of active oxygen are present.

Addition of small amounts of known bleach stabilizers such as phosphonates, borates or metaborates and metasilicates and magnesium salts such as magnesium sulfate may be useful.

In addition to the manganese oxalates according to the invention, it is possible to use conventional bleach activators, that is to say compounds which give perbenzoic acid which is optionally substituted under perhydrolysis conditions and / or peroxycarboxylic acids having 1 to 10 C atoms, in particular 2 to 4 C atoms. Suitable are the customary bleach activators cited at the outset which carry O- and / or N-acyl groups of the stated C atom number and / or optionally substituted benzoyl groups. Preference is given to polyacylated alkylenediamines, in particular tetraacetylethylenediamine (TAED), acylated glycolurils, in particular tetraacetylglycoluril (TAGU), acylated triazine derivatives, in particular 1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine (DADHT), acylated phenylsulfonates , in particular nonanoyl or Isononanoyloxybenzolsulfonat, acylated polyhydric alcohols, in particular triacetin, ethylene glycol diacetate and 2,5-diacetoxy-2,5-dihydrofuran and acetylated sorbitol and mannitol, and acylated sugar derivatives, in particular pentaacetylglucose (PAG), Pentaacetylfruktose, Tetraacetylxylose and Octaacetyllactose and acetylated , possibly N-alkylated glucamine and gluconolactone. Also from the German patent application DE 44 43 177 known combinations of conventional bleach activators can be used. In a preferred embodiment of the use according to the invention, such a compound releasing peroxocarboxylic acid under perhydrolysis conditions is used simultaneously with the manganese oxalate and the hydrogen peroxide-generating compound. In a preferred embodiment of inventive agents, 1 to 10% by weight, in particular 2 to 6% by weight, of such compound releasing peroxycarboxylic acid under perhydrolysis conditions are present.

The term bleaching is understood to mean here both the bleaching of dirt located on the hard surface, in particular tea, and the bleaching of dirt removed from the hard surface in the dishwashing liquor.

Essentially, the use of the present invention is to create conditions on a hard surface contaminated with colored stains, under which a peroxidic oxidizing agent and the manganese oxalates can react with each other, with the aim of obtaining more strongly oxidizing secondary products. Such conditions are especially present when the reactants meet in aqueous solution. This can be done by separately adding the peroxygen compound and the manganese oxalate to an optionally detergent-containing solution. However, the inventive method is particularly advantageous using a Hard surface cleaning agent containing a manganese oxalate and optionally a peroxygen-containing oxidizing agent. The peroxygen compound may also be added to the solution separately, in bulk or as a preferably aqueous solution or suspension, if a non-oxygenated cleaner is used.

The cleaning agents, which may be in the form of granules, powdered or tablet-form solids, other shaped bodies, homogeneous solutions or suspensions, may contain, in principle, all known ingredients customary in such agents, as well as the said manganese oxalate. The compositions may in particular contain builder substances, surface-active surfactants, peroxygen compounds, water-miscible organic solvents, sequestering agents, electrolytes, pH regulators and other auxiliaries, such as silver corrosion inhibitors, foam regulators, additional peroxygen activators and dyes and fragrances.

In addition, a hard surface cleaner can contain abrasive components, in particular from the group comprising quartz flours, wood flours, plastic flours, chalks and glass microspheres, and mixtures thereof. Abrasives are preferably not more than 20 wt .-%, in particular from 5 to 15 wt .-%, contained in the cleaning agents.

An apparatus for machine dishwashing may contain from 15 to 65% by weight, especially from 20 to 60% by weight of water-soluble builder component, from 5 to 25% by weight, especially from 8 to 17% by weight of oxygen-based bleach, in each case to the total agent, and each containing 0.05 to 1.5 wt .-% manganese oxalate. Such an agent is particularly low alkaline, that is, its 1-weight percent solution has a pH of 8 to 11.5, preferably 9 to 11.

In principle, all water-soluble builder components in detergents come in detergents for dishwashing machines commonly used builders, for example, alkali phosphates, which may be in the form of their alkaline, neutral or acidic sodium or potassium salts. Examples of these are trisodium phosphate, tetrasodium diphosphate, disodium dihydrogen diphosphate, pentasodium triphosphate, so-called sodium hexametaphosphate and the corresponding potassium salts or mixtures of sodium and potassium salts. Their amounts may be in the range of up to about 60 wt .-%, in particular 5 to 20 wt .-%, based on the total mean. Further possible water-soluble builder components, in addition to polyphosphonates and phosphonate alkyl carboxylates, are, for example, organic polymers of the type of the polycarboxylates of native or synthetic origin, which act as co-builders, in particular in hard water regions. For example, polyacrylic acids and copolymers of maleic anhydride and acrylic acid and the sodium salts of these polymeric acids are suitable. Commercially available products are, for example, Sokalan ™ CP 5, CP 10 and PA 30 from BASF. Examples of co-builder polymers of native origin include oxidized starch and polyamino acids such as polyglutamic acid or polyaspartic acid. Other possible builder components are naturally occurring hydroxycarboxylic acids such as mono-, dihydroxysuccinic, alpha-hydroxypropionic and gluconic acid. Preferred organic builder components include the salts of citric acid, especially sodium citrate. As sodium citrate, anhydrous trisodium citrate and preferably trisodium citrate dihydrate are suitable. Trisodium citrate dihydrate can be used as a fine or coarse crystalline powder. Depending on the pH finally set in the agents, the acids corresponding to the said co-builder salts may also be present.

The enzymes optionally present in the compositions include proteases, amylases, pullulanases, cutinases and / or lipases, for example proteases such as BLAP ™, Optimase ™, Opticlean ™, Maxacal ™, Maxapem ™, Durazym ™, Purafect ™ OxP, Esperase ™ and / or Savinase ™, amylases such as Termamyl ™, Amylase-LT ™, Maxamyl ™, Duramyl ™ and / or Lipases such as Lipolase ™, Lipomax ™, Lumafast ™ and / or Lipozym ™. The enzymes used may be adsorbed to carriers and / or embedded in encapsulants to protect against premature inactivation. They are preferably present in the cleaning agents in amounts of up to 10% by weight, in particular from 0.05 to 5% by weight, particular preference being given to using enzymes which are stabilized against oxidative degradation.

The machine dishwashing detergents preferably contain the customary alkali carriers, for example alkali metal silicates, alkali metal carbonates and / or alkali metal bicarbonates. The alkali carriers used conventionally include carbonates, bicarbonates and alkali silicates having a molar ratio of SiO ₂ / M ₂ O (M = alkali metal) of from 1: 1 to 2.5: 1. Alkali silicates may be present in amounts of up to 40% by weight. in particular from 3 to 30% by weight, based on the total agent. The alkali carrier system preferably used in the compositions is a mixture of carbonate and bicarbonate, preferably sodium carbonate and bicarbonate, which may be contained in an amount of up to 50% by weight, preferably 5 to 40% by weight.

In a further agent 20 to 60 wt .-% of water-soluble organic builder, in particular alkali citrate, 3 to 20 wt .-% alkali carbonate and 3 to 40 wt .-% Alkalidisilikat included.

Surfactants, in particular anionic surfactants, zwitterionic surfactants and preferably weakly foaming nonionic surfactants may also be added to the compositions if appropriate, which serve to better remove greasy soilings, as wetting agents and, if appropriate, in the course of the preparation of the cleaning agents as granulation auxiliaries. Their amount can be up to 20 wt .-%, in particular up to 10 wt .-% and is preferably in the range of 0.5 to 5 wt .-%. Usually, extremely low-foam compounds are used in particular in detergents for use in automatic dishwashing processes. For this preferably include C ₁₂ -C ₁₈ -Alkylpolyethylenglykol-polypropylene glycol ethers, each with at 8 mol ethylene oxide and propylene oxide in the molecule. But you can also use other known low-foam nonionic surfactants, such as C ₁₂ -C ₁₈ alkylpolyethylene glycol polybutylenglykolether with up to 8 moles of ethylene oxide and butylene oxide in the molecule, endgruppenverschlossene Alkylpolyalkylenglykolmischether and the foaming, but ecologically attractive C ₈ -C ₁₄ - Alkylpolyglucoside having a degree of polymerization of about 1 to 4 and / or C ₁₂ -C ₁₄ alkyl polyethylene glycols having 3 to 8 ethylene oxide units in the molecule. Also suitable are surfactants from the family of glucamides, such as, for example, alkyl-N-methylglucamides, in which the alkyl moiety preferably originates from a fatty alcohol with the C chain length C ₆ -C ₁₄ . It is partially advantageous if the surfactants described are used as mixtures, for example the combination of alkyl polyglycoside with fatty alcohol ethoxylates or glucamide with alkyl polyglycosides. The presence of amine oxides, betaines and ethoxylated alkylamines is also possible.

To effect silver corrosion protection, silverware inhibitors can be used in dishwashing detergents. Preferred silver corrosion inhibitors are organic sulfides such as cystine and cysteine, di- or trihydric phenols, optionally alkyl- or aryl-substituted triazoles such as benzotriazole, isocyanuric acid, titanium, zirconium, Hafhium-, cobalt or cerium salts and / or complexes, in which Metals depending on the metal in one of the oxidation states II, III, IV, V or VI.

In order to prevent glass corrosion during the rinse, corresponding inhibitors can be used in dishwashing detergents. Particularly advantageous here are crystalline layered silicates and / or zinc salts. The crystalline layered silicates are sold, for example, by the company Clariant under the trade name Na-SKS, z. Na-SKS-1 (Na ₂ Si ₂₂ O ₄₅ .xH ₂ O, Kenyaite), Na-SKS-2 (Na ₂ Si ₁₄ O ₂₉ .xH ₂ O, magadiite), Na-SKS-3 (Na ₂ Si ₈ O ₁₇ .xH ₂ O) or Na-SKS-4 (Na ₂ Si ₄ O ₉ .xH ₂ O, makatite). Of these, especially Na-SKS-5 (alpha -Na ₂ Si ₂ O ₅ ), Na-SKS-7 (beta-Na ₂ Si ₂ O ₅ , natrosilite), Na-SKS-9 (NaHSi ₂ O ₅ .H ₂ O), Na-SKS-10 (NaHSi ₂ O ₅ .3H ₂ O, Kanemite), Na-SKS-11 (t-Na ₂ Si ₂ O ₅ ) and Na-SKS-13 (NaHSi ₂ O ₅ ), but especially Na-SKS-6 (delta-Na ₂ Si ₂ O ₅ ). An overview of crystalline phyllosilicates can be found, for. In the in " Soap-oil-grease waxes, 116 vintage, No. 20/1990 "on pages 805-808 published article.

In the context of the present application, preferred automatic dishwashing or automatic dishwashing assistants have a weight fraction of the crystalline layered silicate of from 0.1 to 20% by weight, preferably from 0.2 to 15% by weight and in particular from 0.4 to 10% by weight. -%, based in each case on the total weight of these funds.

In a further preferred embodiment, automatic dishwashing or dishwashing auxiliaries comprise at least one zinc salt selected from the group of organic zinc salts, preferably from the group of soluble organic zinc salts, more preferably from the group of soluble zinc salts of monomeric or polymeric organic acids, in particular from the group zinc acetate , Zinc acetylacetonate, zinc benzoate, zinc formate, zinc lactate, zinc gluconate, zinc ricinoleate, zinc abietate, zinc valerate, zinc p-toluenesulfonate.

For the purposes of the present application, automatic dishwashing or automatic dishwashing aids in which the proportion by weight of the zinc salt relative to the total weight of this agent is 0.1 to 10% by weight, preferably 0.2 to 7% by weight and in particular 0, are preferred , 4 to 4 wt .-% and regardless of which zinc salts are used, in particular therefore irrespective of whether organic or inorganic zinc salts, soluble or non-soluble zinc salts or mixtures thereof are used.

If the cleaning agents, for example in the presence of anionic surfactants, foam too much during use, they may still contain up to 6% by weight, preferably about 0.5 to 4% by weight, of a foam-suppressing compound, preferably from the group of silicone oils , Mixtures of silicone oil and hydrophobized silica, paraffins, paraffin-alcohol combinations, hydrophobicized silica, bis-fatty acid amides, and other other known commercially available defoamers. Other optional ingredients in the compositions are, for example, perfume oils.

Among the organic solvents which can be used in the compositions, in particular if they are in liquid or pasty form, are alcohols having 1 to 4 C atoms, in particular methanol, ethanol, isopropanol and tert-butanol, diols having 2 to 4 C atoms, in particular ethylene glycol and propylene glycol, and mixtures thereof and the derivable from said classes of compounds ethers. Such water-miscible solvents are preferably present in the detergents not more than 20% by weight, in particular from 1 to 15% by weight.

To establish a desired, by the mixture of the other components not automatically resulting pH, the agents can system and environmentally acceptable acids, in particular citric acid, acetic acid, tartaric acid, malic acid, lactic acid, glycolic acid, succinic acid, glutaric acid and / or adipic acid, but Also, mineral acids, in particular sulfuric acid or alkali metal hydrogen sulfates, or bases, in particular ammonium or alkali metal hydroxides. Such pH regulators are preferably not more than 10% by weight, in particular from 0.5 to 6% by weight, in the compositions.

The preparation of the solid agents presents no difficulties and may be carried out in a manner known in the art, for example by spray-drying or granulation, wherein peroxygen compound and bleach catalyst are optionally added separately later.

Detergents in the form of aqueous or other conventional solvent-containing solutions are particularly advantageous simple mixing of the ingredients that can be added in bulk or as a solution in an automatic mixer made.

The compositions are preferably in the form of powdered, granular or tablet-like preparations which are prepared in a manner known per se, for example by mixing, granulating, roller compacting and / or spray-drying the thermally stable components and admixing the more sensitive components, in particular enzymes, bleaches and the like Bleaching catalyst are expected to be produced.

For the preparation of detergents in tablet form, the procedure is preferably such that all ingredients are mixed together in a mixer and the mixture by means of conventional tablet presses, such as eccentric or rotary presses, with pressing pressures in the range of 200x10 ⁵ Pa to 1500x10 ⁵ Pa pressed.

This gives unbreakable, yet sufficiently rapidly soluble tablets under application conditions with flexural strengths of normally over 150 N. Preferably, a tablet thus produced has a weight of 15 to 40 g, in particular from 20 to 30 g, with a diameter of 35 to 40 mm.

The preparation of compositions in the form of non-dusting, storage-stable free-flowing powders and / or granules with high bulk densities in the range of 800 to 1000 g / l can be effected by subjecting the builder components with at least a proportion of liquid mixture components in a first process step Increase the bulk density of this premix and subsequently - if desired, after an intermediate drying - the other constituents of the agent, including the bleach catalyst, combined with the thus obtained premix.

Means for cleaning dishes can be used both in household dishwashers and in commercial dishwashers become. The addition is done by hand or by means of suitable metering devices. The application concentrations in the cleaning liquor are generally about 1 to 8 g / l, preferably 2 to 5 g / l.

A machine wash program is generally supplemented and terminated by a few rinses of clear water following a cleaning cycle and a rinse cycle with a common rinse aid. After drying, when using agents according to the invention, a completely clean and hygienically perfect dishes are obtained.

Examples Preparation of manganese (II) oxalate dihydrate.

176.0 g (1.95 mol) of oxalic acid in 4200 ml of water were placed in a 10 l four-necked round-bottomed flask equipped with stirrer, thermometer and reflux condenser and the resulting solution was added dropwise at room temperature to a solution of 318.6 g (1.30 mol ) Manganese (II) acetate tetrahydrate in 2100 ml of water and stirred after the addition for 15 min. Subsequently, the reaction mixture was heated to reflux and stirred for a further 30 min. After cooling to room temperature, the white precipitate was filtered off, washed three times with 200 ml of water and dried overnight in a vacuum oven at room temperature.
226.5 g of white, crystalline manganese (II) oxalate dihydrate were obtained

Examples 1 - 5

A cleaning agent (V1) containing 44 parts by weight of sodium tripolyphosphate, 30 parts by weight of sodium carbonate, 10% by weight of phyllosilicate SKS-6, 10 parts by weight of sodium perborate monohydrate, 1.5 parts by weight of protease and amylase Granules, 3 parts by weight of nonionic surfactant and 2 parts by weight of N, N, N'N'-tetraacetylethylenediamine (TAED) in granular form and detergent according to the invention (M1 to M3), otherwise composed as V1 but containing manganese oxalates according to the invention were tested for their tea-removing properties. In V 2 and V3 other non-inventive manganese salts or mixtures consisting of manganese salts and oxalic acid are listed as comparative examples.

For the production of standardized tea coverings, tea cups were immersed in a 70 ° C. hot tea solution 25 times. Then each of the tea solution was added to each tea cup and the cup dried in a drying oven.

The rinsing tests were carried out in a dishwasher Miele G 688 SC at 45 ° C using water of water hardness 21 ° dH in the presence of 100 g of IKW test soil. The pad removal was then graded visually on a scale from 0 (= very strong pad) to 100% (= no pad). Table 1: test product rating V1 (cleaner) 37% V2 (cleaner + 100 mg Mn (II) sulphate) 55% V3 (cleaner + 50 mg Mn (II) SO ₄ + 50 mg oxalic acid) 73% M1 (cleaner + 100 mg Mn (II) oxalate dihydrate) 80% M2 (cleaner + 100 mg Mn (III) oxalate trihydrate) 78% M3 (cleaner + 50 mg Mn (II) oxalate dihydrate) 65%

The evaluation of the means M1 to M3 given in Table 1 are significantly better than the value for the comparative product V1 and the comparative experiments V2 and V3.

It can be seen that a significantly better bleaching effect can be achieved by the use according to the invention.

Substantially similar results were obtained when replacing the sodium perborate with sodium percarbonate.

Claims (9)

1. The use of manganese oxalates in cleaning compositions for hard surfaces as bleach catalysts for enhancing the bleaching action of inorganic peroxygen compounds in the bleaching of colored stains.
2. The use as claimed in claim 1, wherein the manganese oxalate is a manganese(II) oxalate dihydrate or a manganese(II) oxalate trihydrate.
3. The use as claimed in claim 1 or 2, wherein the inorganic peroxygen compounds are alkali metal perborate mono- or tetrahydrate and/or alkali metal percarbonate.
4. The use as claimed in claim 3, wherein the alkali metal is sodium.
5. The use as claimed in claim 1, wherein free oxalic acid is additionally used.
6. The use as claimed in one or more of claims 1 to 5, wherein tetraacetylenediamine is used additionally.
7. The use as claimed in one or more of claims 1 to 6, wherein the cleaning composition for hard surfaces comprises the peroxygen compound and 0.025 to 2.5% by weight of manganese oxalate.
8. The use as claimed in claim 7, wherein the cleaning composition for hard surfaces comprises the peroxygen compound and 0.05 to 1.5% by weight of manganese oxalate.
9. The use as claimed in one or more of claims 1 to 8, wherein the cleaning composition for hard surfaces is a dishwashing detergent.