SE468518B - STABILIZED TEXTILE SOFTWARE ENZYMINE CONTINUOUS PREPARED LIQUID DETERGENT COMPOSITION AND ITS APPLICATION IN WASHING TEXTILES - Google Patents

Description

468 10 15 20 25 30 518 containing enzyme stabilizers which are otherwise effective in non-fortified formulations. Furthermore, the incorporation of an enhancer into a liquid detergent composition adds an additional problem, namely the ability to form a stable single phase composition, the solubility of sodium tripolyphosphate is e.g. relatively limited in aqueous compositions, and especially in the presence of anionic and nonionic detergents.

GB patent application 2,079,305, published January 20, 1982, discloses an aqueous fortified enzyme-containing liquid detergent composition which is stabilized by a mixture of a polyol and boric acid. As noted in the examples in the said British patent application, relatively large amounts of glycerol are required to stabilize the enzymes in the composition.

Nevertheless, it is hereinafter demonstrated in the present description that the enzyme stabilizing effect given by a mixture of glycerin and borax in an enhanced aqueous liquid detergent composition is relatively modest.

In EP publication no. 0126505 discloses an aqueous enzyme containing liquid detergent composition containing an enzyme stabilizing mixture consisting of certain dicarboxylic acids and borax. The dicarboxylic acids are recommended as a substitute for a polyol such as glycerol in known enzyme stabilizing mixtures containing glycerol and a boron compound. However, such dicarboxylic acid-borax mixtures as well as the aforementioned mixtures of glycerin and borax are incapable of providing anything other than a modest stabilizing effect in the present liquid fortified detergent compositions.

The present invention provides a stabilized fabric softening enhanced enzyme-containing liquid detergent composition comprising: ... dhülvnum 10 15 20 25 a) b) c) d) e) f) 468 518 ca. 5 - 20% by weight of one or more surfactant detergent compounds selected from the group consisting of anionic, nonionic and amphoteric detergent compounds, approx. 5 - 30% by weight of one or more builder salts selected from the group consisting of alkali metal tripolyphosphates, alkali metal carbonates, alkali metal nitrilotriacetates and polyacetal carboxylates, approx. 5 to 20% by weight of a swelling bentonite clay, an effective amount of an enzyme or an enzyme mixture selected from the group consisting of alkaline protease enzymes and alpha-amylase enzymes, an enzyme stabilizing system containing, based on the weight of the detergent composition, (i) approx. 1 - 10% glycerin, (ii) ca. 1-8% of a boron compound selected from the group containing boric acid, boron oxide and alkali metal borates, and (iii) approx. 0.5 - 8% of a carboxylic acid compound selected from the group consisting of mono-, di- and / or polycarboxylic acids having 1 to 8 carbon atoms and water-soluble salts thereof, and balance water and any perfume and other additives.

According to a preferred embodiment of the invention, the liquid detergent composition a) b) comprises approx. 5 - 15% of an alkali metal alkylbenzene sulfonate, wherein the alkyl group contains 12 - 15 carbon atoms, approx. 5, - 5% of an alkali metal alkyl polyethoxy sulphate, wherein the alkyl group contains 10 - 18 carbon atoms and the polyethoxide part comprises 3 - 11 ethylene oxide groups, -68 in which the weight ratio a) to b) amounts to approx. 2: 1 - ca. 6: 1, c) ca. 5 - 20% sodium tripolyphosphate, d) approx. 1-10% sodium carbonate, sodium bicarbonate or mixtures thereof, the weight ratio c) to d) amounting to approx. 2: 1 - ca. 6: 1, e) ca. 10-15% of a sodium bentonite, f) an effective amount of the above enzyme or enzyme mixture, g) an enzyme stabilizing system containing, based on the weight of the detergent composition, (i) approx. 1-5% glycerin, (ii) ca. 1-5% of an alkali metal borate and (iii) approx. 0.5 - 4% of said carboxylic acid compound, and h) balance water and any perfume and other additives.

In accordance with the process of the invention, washing of stained and / or soiled materials is accomplished by contacting these materials with an aqueous solution of the aforementioned liquid detergent compositions.

The liquid detergent described is a commercially acceptable high performance laundry detergent which satisfactorily cleans laundry containing both oily and particulate soils. In addition, the described compositions can be used for pre-treatment of heavily soiled areas, such as collars and cuffs on garments to be washed.

The present invention is based on the discovery of a three component enzyme stabilizing system as defined herein which provides an enzyme stabilizing effect for the liquid detergent compositions of the invention which far exceeds that obtainable with conventional enzyme stabilizers. .

The enzyme stabilizing effect thus obtained reflects a synergism among the three components. In accordance with the invention, the enzyme stability provided by a mixture of glycerin and borax or a mixture of borax and a dicarboxylic acid as described in the prior art can be synergistically improved by the use of the three-component stabilization system defined herein in the present invention. the liquid compositions for raising the level of enzyme stability significantly above that produced by either the mixture of glycerin and borax or the mixture of borax and dicarboxylic acid, when used independently as enzyme stabilizers. For commercial purposes, a desired enzyme stability generally corresponds to a half-life of about one week at a temperature of approx. 43 ° C (110 ° F).

The enzyme stabilizing system of the invention is a mixture of glycerin, a boron compound selected from the group consisting of boric acid, boron oxide and an alkali metal borate and a carboxylic acid compound as defined herein. The weight of the stabilizing system in the present reinforced liquid detergent compositions is generally about 3 - 25% by weight, preferably approx. 6 - 15% by weight. The weight ratio of glycerin to borax in the stabilizing mixtures is generally approx. 05, - 3. The preferred amount of glycerin in the composition is approx. 1-5% by weight, the preferred amount of boron compound is approx. 1-5% by weight and the preferred amount of carboxylic acid is about 0.5 - 4% by weight, based on the weight of the composition.

The carboxylic acid compounds useful in the enzyme stabilizing system of the invention include saturated as well as unsaturated mono-, di- and polycarboxylic acids having 1 to 8 carbon atoms, which include oxalic acid (HOOCCOOH), malonic acid (HOOCCHZCOOH), maleic acid (HOOCCH: CHCOOH ) and succinic acid (HOOCCHZCHZCOOH). The carboxylic acids may contain hydroxy or amino substituents such as e.g. malic acid (HOOCCHOHCHZCOOH), tartaric acid (dihydroxy succinic acid), aspartic acid (amino succinic acid) and citric acid. Preferred carboxylic acids according to the invention are aspartic acid, tartaric acid, malonic acid and malic acid. From a commercial point of view, a particularly preferred carboxylic acid compound is citric acid and / or its salts, due to their relatively low cost.

The alkaline proteolytic enzymes suitable for the present compositions include the various commercial liquid enzyme formulations used for use in detergent compositions. Powdered enzyme preparations can also be used, although this is generally less convenient for incorporation into the enhanced liquid detergent compositions. Thus, suitable liquid enzyme formulations include "Alcalase" and "Esperase" sold by Novo Industries, Copenhagen, Denmark and "Maxatase" and "AZ-Proteas" sold by Gist-Brocades, Delft, The Netherlands.

Suitable liquid enzyme formulations of OC-amylase include those sold by Novo Industries and Gist-Brocades under the trademarks "Termamyl" and "Maxamyl" respectively.

"Esperase" is particularly preferred for the present compositions, due to its optimized activity at the higher pH values corresponding to the enhanced detergent compositions.

The preferred detergents for use in the present liquid compositions are the synthetic anionic detergent compounds and in particular a mixture of higher alkyl benzene sulfonate and alkyl polyethoxy sulfate. Although other water-soluble higher alkylbenzene sulfonates may also be present in the present formulations, such as potassium salts and in some cases the ammonium or alkanolammonium salts, in some cases, it has been found that the sodium salt is highly preferred. The higher alkylene in the alkylbenzene sulfonate contains 12 to 15 carbon atoms and preferably 13 carbon atoms. The alkyl polyethoxy sulfate, which may also be called sulfated polyethoxylated higher linear alcohol or the sulfated condensation product. of a higher fatty alcohol and ethylene oxide or polyethoxylene glycol, is of the type in which the alkyl group has 10 to 18 carbon atoms and preferably 12 to 15 carbon atoms, eg about 13 carbon atoms, and which comprises 3 to 11 ethylene oxide groups, preferably 3 to 7, more preferably 3-5 and most preferably 3 or about 3 ethylene oxide groups.

The ratio of alkylbenzenesulfonate to polyethoxy sulfate in the detergent mixture preferably amounts to approx. 2: 1 - 6: 1 and most preferably approx. 2: 1 - 4: 1, expressed by weight. At ratios above 5: 1, the physical stability of the product can be adversely affected.

Under suitable circumstances, other anionic detergents such as fatty alcohol sulphates, paraffin sulphonates, olefin sulphonates, monoglyceride sulphates, sarcosinates and similarly acting detergents, preferably in the form of the alkali metal salts, e.g. sodium, be present, sometimes as a partial replacement for the aforementioned synthetic organic detergents, but generally, if present, in addition to said detergents. Normally the supplementary detergents are sulphated or sulphonated products (usually in the form of the sodium salts) and contain long-chain (8 to 20 carbon atoms) linear or fatty alkyl groups. In addition to any additional anionic synthetic organic detergents, nonionic and amphoteric materials may also be present, such as the Neodols sold by Shell Chemical Company, which are condensation products of ethylene oxide and higher fatty alcohols, e.g., Neodol 23- 6.5, which is a condensation product of a higher fatty alcohol with approx. 12 - 13 carbon atoms with approx. 6.5 moles of ethylene oxide. Examples of the various detergents and (TÅ OO (fl ... x OO 10 15 20 25 30 classes of detergents mentioned can be found in the text Surface Active Agents, volume II, by Schwartz, Perry and Berch (Interscience Publishers, 1958), and these descriptions are incorporated herein by reference.

The builder salt combination of the present invention, which has been found to satisfactorily improve the cleaning ability of the mixture of synthetic anionic organic detergents and provide the desired pH in the liquid detergent and in the wash water, is a mixture of sodium tripolyphosphate and sodium carbonate. The builder salts are used in the present compositions in amounts which generally constitute approx. 5 - 25% by weight. For the preferred builder salt combination, sodium tripolyphosphate is present in amounts of about 5 - 20%, preferably 10 - 16%, and sodium carbonate is present in an amount of 1 - 10% by weight, preferably 3 - 7% by weight, the weight ratio of tripolyphosphate to carbonate in the preferred builder mixtures amounting to approx. . 2: 1 - 6: 1, and most preferably approx. 2: 1 - 4: 1. As used herein, the term alkali metal "carbonates" or "carbonate" includes the carbonates, bicarbonates and sesquicarbonates of said alkali metal.

For best preparation, easier mixing and good end-use properties, it is preferred that the sodium tripolyphosphate has a low content of phase I-type tripolyphosphate.

Thus, the phase I type poly polyphosphate content should normally be less than 30% of the tripolyphosphate used. Although in some cases incompletely neutralized tripolyphosphate can be used, the phosphate used can normally be considered to be free of PO 5 3 10 'such as when potassium salts of other materials are present, ionic sodium tripolyphosphate. Of course, in some cases, exchange in an aqueous medium may result. in that salts other than sodium tripolyphosphate are present, but for the purpose of the present specification it is believed that sodium tripolyphosphate in the form of the pentasodium salt, the material normally charged to the mixer to produce it present liquid detergent, be the tripolyphosphate used.

Other preferred builder salts, which may be used in place of or in addition to sodium tripolyphosphate and sodium carbonate, include a polyacetal carboxylate as described herein (NTA). Of the mentioned water-soluble builder salts the utilization and sodium nitrilotriacate Of course, different can be mixed. Nevertheless, the tripolyphosphate-carbonate mixture described has been found to be most preferred, although the other enhancers and mixtures thereof also work. Other builders that can be used as a supplement in addition to the proportions of the above-mentioned builders include other phosphates such as tetrasodium pyrophosphate or tetracaliam pyrophosphate, sodium bicarbonate, sodium citrate, sodium gluconate, sodium silicate and sodium sesquicarbonate. Among the water-insoluble builders that can be used are the zeolites, such as Zeolite A, usually in the form of its crystalline hydrate, although amorphous zeolites may also be useful.

Polyacetal carboxylates are generally described in U.S. Pat. 4,144,226 and 4,315,092. U.S. Pat. 4,146,495 discloses detergent compositions containing polyacetal carboxylates as builders.

The polyacetal carboxylates useful herein as builders can be considered to be those described in U.S. Pat. 4,144,226 and can be prepared by the method described therein.

A typical such product has the formula R1 - (CHO) n - R2 COOM where M is selected from the group consisting of alkali metal, ammonium, alkyl groups having 1-4 carbon atoms, tetraalkylammonium->> groups and alkanolamine groups, both having 1 to 4 carbon atoms in its alkyl groups, on average amounting to at least 4 and R 1 and R 2 are any chemically stable groups which stabilize the polymer against rapid depolymerization in alkaline solution. Preferably the polyacetal carboxylate is one in which M is alkali metal, e.g. sodium, n is 50 - 200, R 1 is CH 3 CH 2 O MOOC II HCO - or H 3 O-CO - II H 3 C MOOC or a mixture thereof, R 2 is OCH 2 CH 3 --CH CH 3 and n 1 is on average 20 - 100, more preferably 30 - 80. the weight average molecular weights of the polymers are normally in the range 2,000 - 20,000, preferably 3,500 - 10,000 and more preferably 5,000 - 9,000, e.g. ca. 8,000.

An especially preferred sodium polyacetal carboxylate is provided by the Monsanto Company and is known as Builder U.

It has an estimated average molecular weight of approx. 8,000 and an active polymer content of approx. 80%. Although the preferred polyacetal carboxylates have been described above, it is understood that they may be replaced in whole or in part by other such polyacetal carboxylates or related organic builder salts as described in the foregoing claims. The above-mentioned patents relating to such compounds, processes for their preparation and compositions in which they may be used Furthermore, the chain terminating groups described in the various patents, in particular U.S. Patent No. 4,144,226, may be used, provided that they have the desired stabilizing properties, which allow the said enhancers to be depolymerized in acidic media, facilitate their biodegradation in effluent streams, but maintain their stability in alkaline media, such as washing solutions.

The bentonite used herein is a colloidal clay (aluminum silicate) containing montmorillonite. Swelling bentonites are generally characterized as sodium bentonites, i.e. bentonite wherein the predominant cation is sodium. Among the sodium bentonite clays, those from Wyoming (commonly referred to as Western or Wyoming bentonite) are particularly preferred.

The swelling capacity of bentonite is generally associated with its fabric softening properties. In water, the swelling capacity of sodium bentonite is in the range of 3 - 20 ml / gram, preferably 7 - 15 ml / gram and its viscosity at 6% concentration in water is generally in the range of 3 - 30 cps, preferably 8 - 30 cps.

Preferred swelling bentonites are sold under the HI-JEL brand by Georgia Kaolin Company. These materials are the same as bentonites previously sold under the MINERAL COLLOID and THIXO-JEL brands. They are selectively extracted and those that are considered to be most useful are available as HI-JEL no. 1, 2, 3 etc., corresponding to THIXO-JEL no. 1, 2, 3 and 4. Such materials have a maximum free moisture content (before addition to the liquid medium) of 4 - 8% and specific weights of approx. 2.6. The bentonite is preferably one that passes through a 200 mesh U.S. Sieve Series sieve (corresponds to hole diameter 0.074 mm) and most preferably passes at least 90% of the particles through a sieve No. 325 (corresponds to hole diameter 0.044 mm), so the corresponding diameter for the bentonite can be considered to be less than 74 microns and more preferably less than about 44 microns.

Typical chemical analyzes for certain bentonites that can be used to prepare the present liquid detergents show that they contain 64.8 - 73, 0% sioz, 14 - 18% Al .1% CaO, 2.3 - 3.4% Fe, O 0.8 - 2.8% Na - 3 'O and ø, 4 - 7, o% K o. 2 2 Although western bentonites are preferred, it is It is also possible to use other bentonites, such as those which can be prepared by treating Italian or similar bentonites containing relatively small proportions of exchangeable monovalent metals (sodium and potassium) with alkaline materials, such as sodium carbonate, to increase the cation exchange capacities of these products. dukter. The Na2O content of the bentonites is considered to be at least approx. 0.5%, preferably at least 1% and more preferably at least 2%, in order for the clay to be satisfactorily swelling with good softening and dispersing properties in aqueous suspension. Preferred swelling bentonites of the types described are sold under the trademarks Laviosa and Winkelmann, e.g. Laviosa AGB and Winkelmann G-13.

Other bentonites that are particularly useful for the present liquid detergent compositions by their white or very light color include the American Colloid Company's Polarite KB 325, a California bentonite, and Georgia Kaolin's GK 129, a Mexican bentonite.

The viscosity of the present liquid detergent is normally in the range of approx. 1,000 - 10,000 cps, preferably 2,000 - 7,000 cps, but products with other suitable viscosities may also be useful. At the mentioned viscosities, the liquid detergent is pourable, stable, non-separating and uniform. The pH of the liquid detergent composition, which is generally in the range of 7 - 11.5 and preferably 8 - 10.5, appears to help maintain product stability and product shelf life.

The following examples illustrate but do not limit the invention. Unless otherwise indicated, all parts are by weight and all temperatures are given in OC.

Example 1 Component Percent Pentanodium tripolyphosphate 11.0 Bentonite (Georgia-Kaolin 129) 12.0 Sodium carbonate - 2.0 Sodium sesquicarbonate 2.0 Sodium linear tridecyl benzenesulfonate 8.0 AEOS (1) 3.0 Carboxymethylcellulose (CMC) 0.2 Optical brighteners 0.3 Perfume 0.4 Enzyme (Esperase 8.0L) (2) 1.0 Glycerin 3.0 Borax 2.5 Citric acid 2.0 Water and additives balance (1) Sodium alkyl polyethoxy sulphate where the alkyl group has 12 to 15 carbon atoms and the polyethoxy group consists of 3 ethoxy groups (2) "Esperase" is sold by Novo Industries and has an activity of 8.0 KNPU / gram. 468 518 10 15 20 25 30 14 The composition shown above was prepared by the following procedure: 30.0 parts of deionized water at 4.4oC (40OF) are added to a suitable mixing apparatus such as a vertical cylindrical tank equipped with a stirrer. With the stirrer adjusted for medium (medium) stirring, a mixture consisting of 2.0 parts of anhydrous soda, 2.0 parts of sodium sesquicarbonate and 0.2 parts of sodium carboxymethylcellulose is incorporated into the water. The stirrer speed is then increased to maximum agitation and a mixture composed of 11.0 parts of pentasodium tripolyphosphate and 12.0 parts of bentonite is slowly added to the mixing apparatus over a period of 101-15 minutes to form a yellowish-white or off-white suspension. The stirring speed is then reduced to a slow / medium setting while adding 8.64 parts of a LTBS slurry with high AI (approx. 55%). Then the solution of optical brightener / paint consisting of 0.3 parts of Tinopal LMS-X (CIBA-GEIGY), 0.99 parts of dye and 4.02 parts of deionized water is added. When a uniform blue-green colored solution is obtained, 0.4 parts of perfume are added to the mixture with stirring. This is accompanied by the slow addition of 3.0 parts of glycerin and 2.5 parts of borax as a two component slurry. Stirring is continued until the mixture has a uniform appearance and then 2.0 parts of citric acid and 9.0 parts of water are added slowly. The agitation of the mixture is then reduced while adding 10.95 parts of a mixed AI detergent base consisting of an LTBS slurry (about 30% AI) and AEOS (about 27.5% AI) to the mixture. This is accompanied by the slow addition of 1.0 part of proteolytic enzyme with continuous stirring until all materials are completely dispersed or dissolved.

Example 2 Enzyme-containing fortified liquid detergent compositions A to G were formulated according to Table 1 below. The percentages indicate the percentages by weight. The arrows indicate the extent to which compositions B to G are identical to composition A.

Table l ln lo Im P11 Im Component ê Q Pentanodium tripolyphosphate 11.0 Bentonite (Georgia-Kaolin 129) 12.0 Sodium carbonate 2.0 Sodium sesquicarbonate 2.0 Sodium linear tridecylbenzenesulfonate 8.0 AEosm _ 3.0 Optical brightness enhancer (Tinopal LMS-X) 0.3 Perfume 0.4 CMC 0.2 Enzyme (2) 1.0 \ / \ / xv x / ~ / \ & Glycerin - 3.0 - 3.0 - - 3.0 Borax - - 2.5 2.5 - 2.5 2.5 Carboxylic acid compound - - - - 2.0 2.0 2.0 Water and additives balance (1) Sodium alkyl polyethoxy sulphate wherein the alkyl group has 12 to 15 carbon atoms and the polyethoxy moiety has 3 ethoxy groups. (2) "Esperase" sold by Novo Industries with an activity of 8,0 KNPU / gram (Kilo Novo protease units / gram).

The enzyme activities of compositions A to F were tested after 7 days of storage at 43.3 ° C (110 ° F). The measured enzyme activity for each composition after this storage period is given in Table 2 as a percentage of the initial value. The various carboxylic acids and salts used in the general formulas of compositions A, B, C, D, E and G are shown in Table 2 as well as the enzyme activities corresponding to each composition. .

Table 2 Enzyme stability Composition A (control) B (with glycerin) C (with borax) D (with glycerin and borax) Composition E (with carboxylic acid compound) wherein the carboxylic acid compound is: (1) Succinic acid (2) Malonic acid (3) Malic acid (4) Tartaric acid (5) Aspartic acid (6) Citric acid (7) Sodium tartrate (8) Sodium citrate Percent active enzyme after 7 days at 43.3 ° C ND * ND ND 50 ND * ND = undetectable (below 10% residual activity) 10 15 20 25 30 468 518 17 Composition G (with glycerin / borax / carboxylic acid compound) Percent active enzyme wherein the carboxylic acid compound is: (1) Succinic acid 70 (2) Malonic acid 70 (3) Malic acid 78 (4) Tartaric acid 73 (5) Aspartic acid 90 (6) Citric acid 74 (7) Sodium tartrate 66 (8) Sodium citrate 52 As shown in Table 2, the control composition as well as compositions B and C containing individual stabilizers in the form of glycerin and borax, respectively, showed essentially no enzyme activity after 7 days of storage at 43, 3 ° C. Since enzyme activities below 10% could not be accurately measured, they are termed "ND". Composition D containing glycerin / borax in the absence of a carboxylic acid compound gave an improvement in enzyme stability compared to composition A, but approx. 50% of the enzyme was deactivated. The various compositions E containing a number of different carboxylic acid compounds as indicated showed no improvement in enzyme stability relative to composition A. However, compositions G formulated in accordance with the invention demonstrate the unexpected and synergistic improvement in enzyme stability achieved with the use of glycerin. / borax in combination with a carboxylic acid compound in the present liquid detergent compositions. It should be noted that almost each of the compositions corresponding to composition G gave a significant improvement in enzyme activity relative to composition D (containing glycerin and borax).

A comparison of the enzyme activities obtained with the compositions D (glycerin / borax) and the different compositions F after 7 days at 43.3 ° C 468 518 10 Composition 18 (borax / carboxylic acid compound) and G (composed according to the invention ) is shown below in Table 3.

Table 3 Enzyme stability Percent active enzyme after 7 days at 43.3 ° C D (glycerin / borax) 50 F (borax / malonic acid) 45 G (glycerin / borax / malonic acid) 70 F (borax / aspartic acid) 72 G (glycerin / borax / aspartic acid 90 F (borax / citric acid) 42 G (glycerin / borax / citric acid) 74 As shown in Table 3, the various compositions G containing a three-component stabilizer system according to the invention provide a synergistic improvement in enzyme stability over compositions D and F assembled in accordance with prior art. p:

Claims (22)

10 15 20 25 1. Strengthened liquid detergent composition, 468 518 19 P a t e n t k r a v Stabilized textile emollient enzyme-containing precursor comprising: a) b) c) d) e) f) 2. n e t e c k n a d ca. 5 - 20% by weight of one or more surfactant detergent compounds selected from the group consisting of anionic, nonionic and amphoteric detergent compounds, approx. 5 - 30% by weight of one or more builder salts selected from the group consisting of alkali metal tripolyphosphates, alkali metal carbonates, alkali metal nitrilotriacetates and polyacetal carboxylates, approx. 5 to 20% by weight of a swelling bentonite clay, an effective amount of an enzyme or an enzyme mixture selected from the group consisting of alkaline protease enzymes and alpha-amylase enzymes, an enzyme stabilizing system containing, based on the weight of the detergent composition, of (i) approx. 1 - 10% glycerin, (ii) ca. 1-8% of a boron compound selected from the group consisting of boric acid, boron oxide and alkali metal borates, and (iii) approx. 0.5 - 8% of a carboxylic acid compound selected from the group consisting of mono-, di- and / or polycarboxylic acids having 1 to 8 carbon atoms and water-soluble salts thereof, and the balance comprising water and any perfume and other additives. Liquid detergent composition according to claim 1, characterized in that it comprises: 468 10 15 20 25 - .. x OO 20 a) approx. 5 - 15% of an alkali metal alkylbenzene sulfonate where the alkyl group contains 12 - 15 carbon atoms, b) approx. 0.5 - 5% of an alkali metal alkyl polyethoxy sulphate where the alkyl group contains 10 to 18 carbon atoms and the polyethoxy group contains 3 to 11 ethylene oxide groups, the weight ratio a) to b) amounting to approx. 2: 1 - ca. 6: 1, c) ca. 5 - 20% sodium tripolyphosphate, d) approx. 1 - 10% sodium carbonate, sodium bicarbonate or mixtures thereof, the weight ratio c) to d) amounting to approx. 2: 1 - ca. 6: 1, e) ca. 10-15% of a sodium bentonite, f) an effective amount of said enzyme or enzyme mixture, g) the enzyme stabilizing system containing, based on the weight of the detergent composition, of (i) approx. 1-5% glycerin, (ii) ca. 1 - 5% of an alkali metal borate and (iii) approx. 0.5 - 4% of said carboxylic acid compound, and h) the balance constituting water and any minor additives. Liquid detergent composition according to claim 2, characterized in that said alkali metal alkyl benzene sulfonate is sodium linear tridecyl benzenesulfonate and said alkali metal alkyl polyethoxy sulfate is one wherein the alkali metal is sodium, the alkyl group contains the poly 3 ethylene oxide groups. Liquid detergent composition according to claim 3, characterized in that the ratio of tridecylbenzenesulfonate to polyethoxy sulfate is approx. 2: 1 - ca. 4: 1. 468 518 21 Liquid detergent composition according to claim 2, characterized in that said boron compound is an alkali metal borate. Liquid detergent composition according to claim 5, characterized in that said borate is borax. Liquid detergent composition according to claim 2, characterized in that it contains approx. 8 - 16% sodium tripolyphosphate and approx. 2 - 6% sodium carbonate, sodium bicarbonate or mixtures thereof. A liquid detergent composition according to claim 2, characterized in that said carboxylic acid compound is aspartic acid or a water-soluble salt thereof. Liquid detergent composition according to claim 2, characterized in that said carboxylic acid compound is tartaric acid or a water-soluble salt thereof. Liquid detergent composition according to claim 2, characterized in that said carboxylic acid compound is citric acid or a water-soluble salt thereof. Liquid detergent composition according to claim 2, characterized in that said carboxylic acid compound is malonic acid or a water-soluble salt thereof. Liquid detergent composition according to claim 2, characterized in that said carboxylic acid compound is malic acid or a water-soluble salt thereof. Washing method, characterized in that stained and / or soiled textiles to be washed are brought into contact with a stabilized enzyme-containing enhanced liquid detergent composition comprising: 468 518 10 15 20 25 a) b) c) d) e) f) 14. 22 ca. 5 - 20% by weight of one or more detergent surfactants selected from the group consisting of anionic, nonionic and amphoteric detergent compounds, approx. 5 - 30% by weight of one or more builder salts selected from the group consisting of alkali metal tripolyphosphates, alkali metal carbonates, alkali metal nitrilotriacetates and polyacetal carboxylates, approx. 5 to 20% by weight of a swelling bentonite clay, an effective amount of an enzyme or an enzyme mixture selected from the group consisting of alkaline protease enzymes and alpha-amylase enzymes, an enzyme stabilizing system containing, based on the weight of the detergent composition, of (i) approx. 1 - 10% glycerin (ii) ca. 1-8% of a boron compound selected from the group consisting of boric acid, boron oxide and alkali metal borates, and (iii) approx. 0.5 - 8% of a carboxylic acid compound selected from the group consisting of mono-, di- and / or polycarboxylic acids having 1 to 8 carbon atoms and water-soluble salts thereof, and the balance being water and any perfume and other additives. in that the Method according to claim 13, characterized in that said liquid detergent composition comprises: a) approx. 5 - 15% of an alkali metal alkylbenzene sulfonate where the alkyl group contains 12 - 15 carbon atoms, b) approx. 0.5 - 5% of an alkali metal alkyl polyethoxy sulphate where the alkyl group contains 10 to 18 carbon atoms and the polyethoxy moiety contains 3 to 11 ethylene oxide groups, and wherein the weight ratio a) to b) amounts to approx. 2: 1 - ca. 6: 1, c) ca. 5.- 20% sodium tripolyphosphate, d) ca. 1 - 10% sodium carbonate, sodium bicarbonate or mixtures thereof, the weight ratio c) to d) amounting to approx. 2: 1 - ca. 6: 1, e) ca. 10-15% of a sodium bentonite, f) an effective amount of said enzyme or enzyme mixture, g) containing the enzyme stabilizing system, based on the weight of the detergent composition of (i) approx. 1-5% glycerin, (ii) ca. 1 - 5% of an alkali metal borate and (iii) approx. 0.5 - 4% of said carboxylic acid compound, and h) the balance constituting water and any minor additives- SGI '. 15. A method according to claim 14, characterized in that said alkali metal alkyl benzene sulfonate is sodium linear tridecyl benzenesulfonate and that said alkali metal alkyl polyethoxy barrel is one in which the alkali metal is sodium, the alkyl group carbonate contains 12 - 15. 3 ethylene oxide groups. Method according to claim 15, characterized in that the ratio of tridecylbenzenesulfonate to polyethoxy sulphate amounts to approx. 2: 1 - ca. 4: 1. 17. A method according to claim 14, characterized in that said boron compound is borax. 468 518 10 15 24 The method of claim 14, wherein the liquid detergent composition contains approx. of 8 to 16% sodium tripolyphosphate and 2 to 6% sodium carbonate, sodium bicarbonate or mixtures thereof. The method of claim 14, that the carboxylic acid compound is aspartic acid or a water-soluble salt thereof. The method of claim 14, wherein the carboxylic acid compound is citric acid or a water-soluble salt or salt thereof thereof. The method of claim 14, wherein the carboxylic acid compound is malic acid or a water-soluble salt of the salt thereof. 22. A method according to claim 14, characterized in that the carboxylic acid compound is malonic acid or a water-soluble salt thereof.