EP0576479B1 - Liquid or paste-like washing product - Google Patents

Abstract

New washing products form suspensions of crystalline, stratified sodium silicates and other components typical of washing products in liquid non-ionic surface-active agents or in mixtures of such surface-active agents with organic solvents selected from the group composed of glycols, glycolethers and glycerine, whereas these washing products should not contain more than 30 wt. % water. The silicates used are compounds having the general formula: NaMSIx?O2x+1?.yH2?O, in which M stands for sodium or hydrogen, x is a number between 1.9 and 4 and y is a number from 0 to 20.

Description

The present invention relates to liquid to pasty detergents which contain silicates and nonionic surfactants.

For a long time, efforts have been made to replace the phosphates previously contained in almost all detergents as builders (builders) with other substances having the same effect, since phosphates can be responsible for the eutrophication of surface waters. Although substitutes were found with the zeolites in the 1970s that met practically all requirements for such substances, so that they have largely displaced the phosphates from detergents, efforts are still being made to find alternative substitutes for phosphates. A recent proposal relates to crystalline, layered sodium silicates of the general formula NaMSi _x O _{2x + 1} .yH₂O, in which M is sodium or hydrogen, x is a number from 1.9 to 4 and y is a number from 0 to 20 (EP 164 514, EP 337 217 and EP 337 219). Layer silicates of this general formula, in which x is preferably a number from 1.5 to 4 and y is less than 2x, are, according to EP 263 520, in a detergent together with polyoxyethylated, long-chain alcohols used. In contrast to amorphous silicates, which have always been used in detergents, sometimes alone or in addition to phosphate, these crystalline, layered silicates presented there have a pronounced binding capacity for calcium and magnesium ions. They were therefore proposed in the above-mentioned patent applications for use in water softening and as components of solid detergents.

These crystalline, layered silicates, however, were also known to be unstable in the presence of polar, protic liquids and to convert into amorphous silicates. With the loss of the layer structure, however, there is inevitably a loss of calcium and magnesium binding capacity, so that an essential function which a detergent builder should then no longer exist. For the These crystalline, layered disilicates therefore did not appear to be suitable for use in liquid or pasty detergents.

Surprisingly, it has now been found that this use in liquid and pasty detergents is nevertheless possible if these detergents contain a liquid phase of a certain composition and the crystalline, layered disilicates are predominantly in suspended form in this liquid phase.

The invention relates to liquid to pasty detergents, the crystalline, layered sodium silicate of the general formula NaMSi _x O2 _{x + 1} .yH₂O, in which M is sodium or hydrogen, x is a number from 1.9 to 4 and y is a number from 0 to 20 mean, wherein this silicate is suspended in a liquid phase, the nonionic surfactants, the formula R- (O-CH₂-CH₂-) _n OH (I), in which R is a long-chain primary or secondary alkyl radical with 8 to 20 C. -Atoms and n are a number between 3 and 20, and optionally organic solvents from the group of glycols and glycol ethers, and not more than 30% by weight, based on the total composition, of water. Agents in which the liquid phase contains not more than 20% by weight, in particular not more than 10% by weight, of water are particularly preferred.

In the new compositions, the decomposition of the crystalline, layered sodium silicates has been suppressed to such an extent that it no longer interferes with the storage times customary for detergents. The builder effect remains at the level necessary for the washing process. Another advantage is that inorganic peroxides can be stably incorporated into these detergents.

The crystalline, layered sodium silicates used according to the invention can be naturally occurring minerals, for example kanemite. However, preference is given to using synthetically produced, layered silicates which have been described in various forms in the literature. The silicates of the formula NaMSi₂O₅ · yH₂O are particularly preferred, of which in turn the beta and delta modifications of Na₂Si₂O₅ are particularly preferred. The crystalline, layered Sodium silicates are preferably contained in the liquid to pasty detergents in amounts between 10 and 50% by weight and in particular in amounts between 20 and 40% by weight, based on the total agent. The crystalline, layered sodium silicates are preferably used in the compositions in the form of very small particles, which are preferably smaller than 100 »m, in particular smaller than 30» m.

The essential components of the liquid phase, in which the crystalline, layered sodium silicates are suspended, contain nonionic surfactants of the formula (I) and optionally organic solvents from the group of glycols and glycol ethers and up to 30% by weight, based on the total Medium, in water. The water content is preferably between 0.5 and 20% by weight, in particular not more than 10% by weight, based on the total composition. The water that is introduced into the medium in the form of water of hydration of solid salts or in a similarly bound form must be included in the calculation. Otherwise, the composition of the liquid phase is preferably chosen so that the pour point of this phase is below 15 ° C., in particular below 10 ° C. These values can easily be achieved by using appropriately liquid nonionic surfactants and / or sufficient proportions of organic solvents and / or water.

The nonionic surfactants of the formula (I) which can be used according to the invention are the addition products of 3 to 20 mol of ethylene oxide (EO) and long-chain primary and secondary alcohols having 8 to 20 C atoms, preferably 10 to 18 C atoms. These are preferably addition products of 4 to 10 mol EO and 1 mol saturated or unsaturated fatty alcohols with 12 to 18 carbon atoms or oxo alcohols of this chain length. Examples of such surfactants are coconut alcohol C _12/14 + 3 EO, coconut alcohol C _12/18 + 5 EO and oleyl cetyl alcohol + 10 EO, and oxo alcohol C _11/13 + 7 EO. The nonionic surfactants of the formula (I) are preferably present in the agents according to the invention in amounts between 10 and 60% by weight, in particular in amounts between 10 and 40% by weight.

As organic solvents, which together with the nonionic surfactants of formula (I) and optionally water, the liquid phase of can form agents according to the invention, primarily water-soluble glycols and glycol ethers and glycerol come into consideration; preferably no other organic solvents are used in addition. The glycols are preferably those having 2 to 6 carbon atoms in the molecule, and the di- and oligomers of propylene glycol and, preferably, ethylene glycol which are liquid at room temperature. For the glycol ethers, the monoethers from methanol, ethanol, propanol or butanol and mono-, di- or triglycols are preferably used. In particular, the ethers contain no more than 10 carbon atoms per molecule. The organic solvent content is preferably not more than 30% by weight, in particular between 0.5 and 10% by weight, based on the detergent as a whole.

Another preferred component of the liquid to pasty detergents according to the invention are inorganic peroxides, which are effective as bleaching agents. In the simplest case, an equal weight of hydrogen peroxide can be used instead of part of the water present in the liquid phase. However, preference is given to using solid inorganic peroxides, which on average are then predominantly also in undissolved, i.e. suspended form. Perborate tetrahydrate, perborate monohydrate and the adduct of H₂O₂ with sodium carbonate, which is also referred to as percarbonate, are very particularly preferred. The solid inorganic peroxides, like the crystalline, layered sodium silicates, are preferably used in the compositions in very finely divided form. Their content in the agents according to the invention can be up to 30% by weight, preferably between 5 and 30% by weight and in particular between 10 and 25% by weight.

In addition to the constituents already mentioned, the detergents according to the invention can contain further active ingredients and auxiliaries as are customary in liquid and pasty detergents, provided that these further ingredients do not impair the stability of the detergents. The following are primarily mentioned as such constituents: surfactants of other types, in particular nonionic and anionic surfactants, further organic or inorganic builders and sequestering agents, foam regulators, graying inhibitors and bleach activators. Further Examples of such auxiliaries and additives are optical brighteners, detergency boosters, enzymes, dyes, perfumes, inorganic salts and preservatives. The total content of the abovementioned active substances and auxiliaries in the agents according to the invention is generally not more than 50% by weight, preferably between 0.5 and 20% by weight, it being possible for the individual components to be present in the agents in dissolved or suspended form.

Additional nonionic surfactants include primarily the addition products of ethylene oxide with polypropylene oxide or with fatty acids, fatty acid amides or alkylphenols with 12 to 18 carbon atoms, and the alkyl glycosides, for example the alkyl glucosides or alkyl polyglucosides available from glucose and long-chain primary alcohols. These alkyl glucosides preferably contain 10 to 14 carbon atoms in the alcohol part and 1 to 3 glucose units per molecule. Nonionic surfactants of the amine oxide type, for example N-cocoalkyl-N, N-dimethylamine oxide and N-tallow alkyl-N, N-dihydroxyethylamine oxide, and the fatty acid alkanolamides can also be suitable. The amount of these nonionic surfactants is generally not more than that of the nonionic surfactants of the formula (I), preferably not more than half of them.

Suitable synthetic anionic surfactants are in particular those of the sulfonate and sulfate type. As surfactants of the sulfonate type come alkylbenzenesulfonates with a C₉-₁₅-alkyl radical, olefin sulfonates, ie mixtures of alkene and hydroxyalkanesulfonates, and disulfonates, such as those obtained, for example, from C₁₂-₁₈ monoolefins with a terminal or internal double bond by sulfonating with gaseous sulfur trioxide and subsequent receives alkaline or acidic hydrolysis of the sulfonation products into consideration. Also suitable are the alkanesulfonates which are obtainable from C₁₂-C₁₈ alkanes by sulfochlorination or sulfoxidation and subsequent hydrolysis or neutralization or by bisulfite addition to olefins, and the esters of α-sulfofatty acids, such as, for. B. the α-sulfonated methyl or ethyl esters of hydrogenated coconut, palm kernel or tallow fatty acids. Suitable surfactants of the sulfate type are the sulfuric acid monoesters of primary alcohols of natural or synthetic origin, ie of fatty alcohols such as, for example, coconut oil, tallow oil, oleyl, lauryl, myristyl, palmityl or stearyl alcohol or the C₁₀-C₂₀ oxo alcohols or secondary alcohols of this chain length. The sulfuric acid monoesters of the aliphatic primary alcohols or ethoxylated secondary alcohols ethoxylated with 1 to 6 mol EO are also suitable. Sulfated fatty acid alkanolamides and sulfated fatty acid monoglycerides are also suitable. The anionic surfactants based on natural raw materials are in particular the wash-active soaps, ie the salts of C₁₂₋C₁₈ fatty acids. The anionic surfactants are present in the agents according to the invention preferably in the form of their sodium salts or in the form of the soluble salts with organic bases, in particular mono-, di- and triethanolamine. The amount of anionic surfactants in the agents according to the invention is preferably not greater than the total amount of nonionic surfactants, in particular it is less than half of the nonionic surfactants. A preferred content is between 5 and 20% by weight, based on the total agent.

Cationic surfactants include, in particular, the quaternary ammonium compounds which, in addition to three shorter alkyl radicals, each with no more than 2 carbon atoms, have a long-chain alkyl radical with 10 to 18 carbon atoms on the nitrogen. Two or three of the shorter alkyl chains can also be closed to form a ring, for example a pyridine ring. Examples of such compounds are N, N, N-trimethyl-N-tetradecylammonium chloride and N, N-dimethyl-N-hydroxyethyl-N-dodecylammonium hydrogen sulfate.

The betaine surfactants are predominantly long-chain quaternary ammonium compounds in which one of the shorter alkyl substituents contains an anionic group, usually a carboxyl group. An example of a betaine surfactant is N, N-dimethyl-N-cocoalkylaminoacetate.

Although the agents according to the invention preferably contain only the crystalline, layered sodium silicates as builders, the agents may also contain further organic and / or inorganic, soluble or insoluble builders. The amount of these additional builder substances is generally not more than the amount of layered silicates and is preferably less than half these silicates; in particular the amount is between 0.1 and 5% by weight, based on the total agent.

The alkaline salts, in particular alkali salts, which not only precipitate or complexly bind calcium ions, but also, as far as possible, bring about a synergistic increase in washing power and have dirt-carrying capacity, should be mentioned as an additional framework substance. Of the inorganic salts, the water-soluble alkali metal or alkali polyphosphates, especially pentasodium triphosphate, are still of importance. Organic builder substances include sequestering agents of the aminopolycarboxylic acid type, such as, for example. Nitrilotriacetic acid, ethylenediaminetetraacetic acid, and higher homologues. Suitable phosphorus-containing organic complexing agents are the water-soluble salts of alkane polyphosphonic acids, amino and hydroxyalkane polyphosphonic acids and phosphonopolycarboxylic acids, such as. B. the compounds methanediphosphonic acid, dimethylaminomethane-1,1-diphosphonic acid, aminotrimethylenephosphonic acid, ethylenediaminetetramethylenephosphonic acid, diethylenetriaminepentamethylenephosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid. These sequestering agents can also be present in smaller amounts as stabilizers for per-compounds. Among the organic framework substances, the N- and P-free polycarboxylic acids that form complex salts with calcium ions are of particular importance. These include low molecular weight compounds, such as. As citric acid, 2,2'-oxydisuccinic acid or carboxymethyloxy succinic acid, and polymeric polycarboxylic acids with a molecular weight of 350 to about 1,500,000 in the form of the water-soluble salts. Particularly preferred polymeric polycarboxylates have a molecular weight in the range from 500 to 175,000, and in particular in the range from 10,000 to 100,000. These include compounds such as, for. B. polyacrylic acid, poly-alphahydoxyacrylic acid and polymaleic acid, and the copolymers of the corresponding monomeric carboxylic acids with one another, for example from acrylic acid and maleic acid, or with other ethylenically unsaturated compounds, such as. B. with vinyl methyl ether. The water-soluble salts of polyglyoxylic acid should also be mentioned.

Particularly suitable water-insoluble inorganic builders are the finely divided synthetic zeolite A-type sodium aluminosilicates containing bound water described in German patent application DE 24 12 837 as phosphate substitutes for detergents and cleaning agents. The cation-exchanging sodium aluminosilicates are used in the usual hydrated, finely crystalline form, i.e. H. they have practically no particles larger than 30 »m and preferably consist at least 80% of particles smaller than 10» m. Their calcium binding capacity, which is determined according to the information in DE 24 12 837, is in the range from 100 to 200 mg CaO / g. The zeolite NaA can be used in particular, also the zeolite NaX and mixtures of NaA and NaX. However, the zeolites are preferably only used in the agents according to the invention if no inorganic peroxides, in particular perborate, are present.

Suitable inorganic, non-complexing salts are the bicarbonates, also known as "washing alkalis", carbonates, borates, sulfates or amorphous silicates of the alkalis. Other structural substances that are also used because of their hydrotropic properties are the salts of the non-capillary-active sulfonic acids containing 2 to 9 carbon atoms, carboxylic acids and sulfocarboxylic acids, for example the alkali salts of alkanoic, benzene, toluene, xylene or cumene sulfonic acids, of sulfobenzoic acids, sulfophthalic acid, sulfoacetic acid, sulfosuccinic acid and the salts of acetic acid or lactic acid.

Examples of foam regulators are the salts of fatty acids with 20 to 24 carbon atoms or long-chain N-alkylaminotriazines with essentially 8 to 18 carbon atoms in the alkyl radical or aliphatic C₁₈-C₄₀ ketones. Paraffin and silicone oil dispersions are preferred, which can optionally be made up with microfine silica. The content can be, for example in the case of soaps, up to 5% by weight of the total composition, in the case of the paraffins and silicone oils it is usually much less, for example 0.05 to 0.5% by weight.

Graying inhibitors include, above all, cellulose ethers, such as carboxymethyl cellulose, methyl cellulose, hydroxyalkyl celluloses and mixed ethers, such as Mention should be made of methylhydroxyethyl cellulose, methyl hydroxypropyl cellulose and methyl carboxymethyl cellulose, furthermore mixtures of various cellulose ethers, in particular mixtures of carboxymethyl cellulose and methyl cellulose.

To strengthen the bleaching effectiveness of the agents according to the invention, they can contain bleach activators in addition to inorganic peroxide. These are acylating agents which react with hydrogen peroxide in the wash liquor to form peroxycarboxylic acids or their salts. Examples of common bleach activators are tetraacetylethylenediamine, pentaacetylglucose and diacetyldioxohexahydrotriazine. In addition to N-acyl compounds and O-acyl compounds, anhydrides can also be used. Bleach activators are preferably used which remain largely undissolved in the liquid portion of the detergent and are therefore predominantly in suspended form. The amounts of bleach activators are preferably not more than 6% by weight, in particular between 2 and 5% by weight, based on the total agent.

Optical brighteners which are particularly suitable for detergents are alkali salts of 4,4-bis (2 '' - anilino-4 '' - morpholino-1,3,5-triazinyl-6 '' - amino) stilbene-2,2'-disulfonic acid or compounds of the same structure which carry a diethanolamino group instead of the morpholino group. Furthermore, brighteners of the type of the substituted diphenylstyryl come into question, e.g. B. the alkali salts of 4,4'-bis (2-sulfostyryl) diphenyl, 4,4'-bis (4-chloro-3-sulfostyryl) diphenyl and 4- (4-chlorostyryl-4 '- ( 2-sulfostyryl) diphenyl.

Detergent boosters are polar long-chain compounds that do not themselves have any surface-active properties, but are able to increase the cleaning effect of the surfactants contained in the detergents. Examples of such compounds are coconut amine + 2 EO and the addition products of glycerol and long-chain α-olefin epoxide.

Enzymes from the class of proteases, lipases and amylases or their mixtures are possible. Bacterial strains or fungi such as Bacillus subtilis, Bacillus licheniformis and are particularly suitable Streptomyces griseus enzymatic substances obtained. The enzymes can be embedded in coating substances to protect them against premature decomposition.

The preparation of the agents according to the invention presents no difficulties. In the simplest case, it is carried out by mixing all the components, the components which later form the liquid phase are advantageously first premixed and then the components to be suspended are introduced into this liquid and mixed homogeneously therewith. The solid constituents of the composition are preferably already based on particle sizes as they are later to be present in the finished composition, but it is also possible to further reduce the size of the suspended solid particles by wet grinding the finished composition. The viscosity of the finished product depends primarily on the solid / liquid ratio in the finished product and on the viscosity of the liquid phase. This in turn can be varied within wide limits by choosing suitable components. For example, the viscosity can be reduced by adding organic solvents and the viscosity can be increased by adding constituents with a thickening effect, such as soaps. Liquid agents according to the invention preferably have viscosities between about 1,000 and about 5,000 mPas, in particular between about 2,000 and about 4,000 mPas, the viscosity being measured using a Brookfield viscometer at 20 ° C. The viscosities of the detergent in paste form, which are preferred because of their particularly high physical stability, go far beyond.

The agents according to the invention are primarily intended for use in textile washing. Depending on the content of active ingredients, they can be used as stand-alone detergents or as detergent additives. However, if the active ingredients are selected appropriately, they are also suitable for cleaning hard surfaces in the home or in the commercial sector. Due to the stability of the suspensions, the agents can also be dosed automatically.

Examples

The paste-like detergents A and B described below were prepared in batches of 50 g each by weighing all the components together and homogenizing the mixtures in a ceramic ball mill (running time 5 minutes). ingredients Percentage by weight A B Crystalline layered disilicate (delta form) (SKS 6, Hoechst AG) 19.1 21.1 Nonionic surfactant Dehydol LST 80/20 (Henkel) 10.5 18.0 Polyethylene glycol 400 5.3 5.4 C _12/13 alkylbenzenesulfonate Na (55% aqueous paste) 33.3 14.5 Sodium perborate tetrahydrate 31.8 22.0 sodium - 9.0 Acrylic acid-maleic acid copolymer (Sokalan CP5, BASF) - 5.0 Tallow fatty acid Na soap - 5.0

Both detergents were stored for 4 weeks at 40 ° C in closed polyethylene bags. No signs of phase separation were seen after this time. Obtaining the crystalline layered The structure of the disilicate was demonstrated with the help of the X-ray reflexes. A loss of active oxygen could not be determined by manganometric titration.

Claims (8)

1. A liquid or paste-form detergent containing crystalline layer-form sodium silicate corresponding to general formula (I) NaMSi_xO_2x+1·yH₂O, where M is sodium or hydrogen, x is a number of 1.9 to 4 and y is a number of 0 to 20, this silicate being suspended in a liquid phase containing nonionic surfactants corresponding to the formula R-(O-CH₂-CH₂-)_n OH (I), in which R is a long-chain primary or secondary alkyl radical containing 8 to 20 C atoms and n is a number of 3 to 20, and optionally organic solvents from the group of glycols, glycol ethers and glycerol, and no more than 30% by weight, based on the detergent as a whole, of water.
2. A detergent as claimed in claim 1, in which the crystalline layer-form sodium silicate corresponds to the formula NaMSiO₂O₅ · yH₂O.
3. A detergent as claimed in claim 2, in which the beta- and/or delta-modification of Na₂Si₂O₅ is present as the crystalline layer-form sodium silicate.
4. A detergent as claimed in any of claims 1 to 3, in which the water content is no more than 20% by weight and preferably no more than 10% by weight.
5. A detergent as claimed in any of claims 1 to 3 containing
      10 to 50 and preferably 20 to 40% by weight crystalline layer-form sodium silicate,
      10 to 60 and preferably 10 to 40% by weight nonionic surfactant corresponding to formula (I),
      5 to 30 and preferably 10 to 25% by weight inorganic peroxide,
      0 to 30 and preferably 0.5 to 10% by weight organic solvent,
      0 to 30 and preferably 0.5 to 20% by weight water    and
      0 to 50 and preferably 0.5 to 20% by weight other typical detergent ingredients.
6. A detergent as claimed in claim 5 in which the nonionic surfactant is selected from the group of adducts of 4 to 10 mol ethylene oxide and 1 mol long-chain alcohol containing 10 to 18 carbon atoms.
7. A detergent as claimed in claim 5, in which the inorganlc peroxide is selected from the group consisting of sodium perborate monohydrate, sodium percarbonate and mixtures thereof.
8. A detergent as claimed in claim 5 in paste form.