LU86526A1 - STABILIZED REINFORCED LIQUID DETERGENT COMPOSITION CONTAINING ENYZMES AND SOFTENING FABRICS, AND PROCESS FOR ITS IMPLEMENTATION - Google Patents

Description

1 i * f i, 1

The present invention relates to reinforced, stable liquid detergent compositions containing enzymes, suitable for formulations for washing or pre-washing laundry. More particularly, the invention relates to aqueous liquid detergent compositions containing enzymes, which contain one or more detergency builders and which are characterized in that they are homogeneous, physically stable liquid compositions.

The prior art has focused strongly on the formulation of stabilized liquid detergent compositions containing enzymes. The desire to incorporate enzymes into detergent compositions is mainly based on the efficacy of the proteolytic and amylolytic enzymes to break down the protein and starchy materials which are found on soiled fabrics, thereby facilitating the removal of stains, for example sauce stains, blood stains, chocolate stains, etc., during laundering. However, the enzyme materials suitable for bleaching compositions, particularly the proteolytic enzymes, are relatively expensive. In fact, they are among the most expensive ingredients of a conventional commercial liquid detergent composition, even if they are present in relatively minor amounts. In addition, enzymes are known to be unstable in aqueous compositions. This is the reason why it is generally necessary to use an excess of enzymes in liquid detergent formulations in order to compensate for the expected loss of enzymatic activity during prolonged periods of storage. Therefore, the prior art abounds with proposals for stabilizing liquid detergent compositions containing enzymes, and in particular unreinforced liquid compositions using various materials which are incorporated into the composition to act as enzyme stabilizers.

In the case of liquid detergent compositions containing a detergency builder, the problem of enzyme instability is particularly acute. This is mainly due to the fact that detergency builders have a destabilizing effect on enzymes, even in compositions containing enzyme stabilizers, which are also effective in unreinforced formulations.

In addition, the incorporation of a detergency builder into a liquid detergent composition poses another problem, namely that of being able to form a stable composition in a single phase; the solubility of sodium tripolyphosphate, for example, being relatively limited in aqueous compositions, and in particular in the presence of anionic and nonionic detergents.

In British Patent Application No. 20,079,305, there is described an enhanced aqueous liquid detergent composition containing enzymes, which is stabilized by a mixture of a polyol and boric acid. As mentioned in the examples of this application, relatively large amounts of glycerol are required to stabilize the enzymes of the composition. However, as highlighted in the remainder of this report, the stabilizing effect of the enzymes provided by a mixture of glycerin and borax in a reinforced aqueous liquid detergent composition is relatively moderate.

The European patent application published under No. 0 126 505 describes an aqueous liquid detergent composition containing enzymes and the like. nant an enzyme stabilization mixture, consisting of certain dicarboxylic acids and borax. Dicarboxylic acids are recommended as a substitute for a polyol such as glycerol in 3 * of known enzyme stabilization mixtures consisting of glycerol and a boron compound. However, the dicarboxylic acid-borax mixtures of this publication, as well as the aforementioned mixture of glycerin and borax of the prior art offer at most a moderate stabilizing effect in; the reinforced liquid detergent compositions of the present invention.

The present invention provides an enhanced, stabilized, liquid, detergent composition containing enzymes, comprising: (a) about 5 to 20% by weight of one or more surfactant detergent compounds selected from anionic, nonionic detergent compounds and amphorae; (b) about 5 to 30% by weight of one or more adjuvant detergency salts, chosen from alkali metal tri-polyphosphates, alkali metal carbonates, alkali metal nitrilotriacetates and polyacetal-carboxylates; (c) about 5 to 20% by weight of a swelling clay of the bentonite type; (d) an effective amount of an enzyme or mixture of enzymes selected from alkaline enzymes of the protease and alpha-amylase type; (e) an enzyme stabilization system containing, based on the weight of the detergent composition, (i) about 1 to 10% glycerin; (ii) about 1 to 8% of a boron compound selected from boric acid, boric oxide and alkate metal borates. lin and (iii) about 0.5 to 8% of a compound of carboxylic acid type chosen from mono-, di- and / or polycarboxylic acids of 1 to 8 carbon atoms and their water-soluble salts? and (f) the remainder consisting of water and optionally perfume and other additives.

In a preferred embodiment of * 4 the invention, the liquid detergent composition comprises: (a) about 5 to 15% of an alkali metal alkylbenzene sulfonate in which the alkyl group contains from 12 to 15 carbon atoms; (b) about 2 to 5% of an alkali metal alkyl polyethoxy sulfa in which the alkyl group contains from 10 to 18 carbon atoms and the polyethoxy chain has from 3 to 11 ethylene oxide groups , 10 the weight ratio of (a) â. (b) being from about 2: 1 to about 6: 1; (c) about 5 to 20% sodium tripolyphosphate; (d) about 1 to 10% sodium carbonate, sodium bicarbonate or a mixture thereof, the weight ratio of (c) to (d) being about 2: 1 to about 6 : 1? (e) about 10 to 15% sodium bentonite; (f) an effective amount of the above enzyme or mixture of enzymes; (g) an enzyme stabilization system containing, based on the weight of the detergent composition, (i) about 1 to 5% glycerin, (ii) about 1 to 5% of an alkali metal borate and (iii ) about 0.5 to 4% of said carboxylic acid compound; and (h) the balance consisting of water and, optionally, perfume and other additives.

According to the process of the invention, the washing of stained and / or soiled materials is carried out by bringing these materials into contact with an aqueous solution of the liquid detergent compositions defined above.

The liquid detergent described is a detergent for heavy laundry laundering, acceptable for commercial purposes, capable of properly cleaning laundry containing both oily and particulate smears. Furthermore, the compositions described can be used for the pretreatment of very dirty parts, such as the collars and the wrists, of articles to be washed.

The present invention is based on the discovery of a three-component enzyme stabilization system as defined herein, which imparts an enzyme stabilization effect to the liquid detergent compositions of the invention far superior to that which can be obtained with conventional enzyme stabilizers. The enzyme stabilization effect thus obtained is the result of a synergy of the three components. According to the invention, the stability of the enzymes 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 improved synergistically by using the stabilizing system with three components defined here in the liquid compositions of the invention, so as to raise the degree of stability of the enzymes far above that provided either by the mixture of glycerin and borax, or by the mixture of borax and d dicarboxylic acid when used independently of one another as enzyme stabilizers. For commercial purposes, desirable enzyme stability generally corresponds to about one week half-life at a temperature of 43 ° C.

The enzyme stabilization system of the invention is a mixture of glycerin, a compound of boron chosen from boric acid, boric oxide and an alkali metal borate and an acid type compound. carboxylic, as defined here. The weight of the stabilizing system contained in the reinforced liquid detergent compositions of the invention generally represents about 3 to 25%, preferably about 6 to 15% of the weight of these compositions. The weight ratio of 6 glycerin to borax in stabilization mixtures is generally about 0.5 to 3. The preferred amount of glycerin in the composition is about 1 to 5%, the preferred amount of boron compound is 05 from about 1 to 5%, and the preferred amount of the carboxylic compound is from about 0.5 to 4%, based on the weight of the composition.

The carboxylic acid compounds which are useful in the enzyme stabilization system of the invention include saturated mono-, di- and polycarboxylic acids as well as unsaturated acids having 1 to 8 carbon atoms, among which may be mentioned oxalic acid (HOOCCOOH), malonic acid (H00CCH2C00H), maleic acid (HOOCCHICHCOOH) and succinic acid (HOOCCH CH ^ COOH). The carboxylic acids can contain hydroxy or amino substituents, such as for example malic acid (H00CCH0HCH2C00H), tartaric acid (dihydro-xysuccinic acid), aspartic acid (amino succinic acid) and l 'citric acid. Preferred carboxylic acids of the invention are aspartic acid, tartaric acid, malonic acid and malic acid. From the commercial point of view, a particularly preferred carboxylic acid is citric acid and / or its salts, because of their relatively low price.

Alkaline proteolytic enzymes suitable for the compositions of the present invention include the various commercially available liquid enzyme preparations which have been developed for use in detergent compositions. Enzyme preparations in powder form are also useful although, as a general rule, they are less convenient to incorporate into reinforced liquid detergent compositions. Thus, suitable liquid enzyme preparations include "Alcalase" · and "Esperase", sold by Novo 7 ï * r \ k

Industries, Copenhagen, Denmark, and "Maxatase" and "AZ-Protease" sold by Gist-Brocades, Délit, Netherlands.

Among the suitable li-05 enzymatic preparations of the type and * -amylase, mention may be made of those sold by Noyo Industries and Gist-Bro-cades under the trade names "Termamyl" and "Maxamyl", respectively.

"Esperase" is particularly preferred for the compositions of the invention, because of its optimized activity at higher pH values corresponding to the reinforced detergent compositions.

Preferred detergents for use in the liquid compositions of the invention are synthetic anionic detergent compounds, and in particular a mixture of (higher alkyl) benzene-tallow onate and alkyl-polyethoxy-sulfate. Although the formulas of the present invention may also contain other water-soluble (higher alkyl) benzene sulfonates, for example potassium salts and, in some cases, ammonium or alkanolammonium salts, where appropriate , it has been found that the sodium salt is the preferred one, which is also the case with regard to the alkyl polyethoxy sulfate detergent component. The alkylbenzene sulfonate is that in which the upper alkyl group contains from 12 to 15 carbon atoms, preferably 13 carbon atoms, alkyl-30 polyethoxy-sulfate, which can also be designated by polyethoxylated sulfated higher linear alcohol or the sulphated condensation product of a higher fatty alcohol and of ethylene oxide or of polyethoxylene glycol, is that in which the alkyl group contains from 10 to 18 carbon atoms, preferably from 12 to 15 atoms of carbon, for example about 13 carbon atoms, and which contains from 3 to 11 ethylene oxide groups 8, preferably from 3 to 7, better still from 3 cl 5, and in particular 3 or about 3 ethylene oxide groups . The ratio of alkyl benzene sulfonate to polyethoxy sulfate in the detergent mixture is preferably about 2: 1 to 6: 1, and more preferably about 2: 1 to 4: 1 by weight. At ratios greater than 5: 1, the physical stability of the product may be adversely affected.

In other appropriate cases, other anionic agents such as fatty alcohol sulfates, paraffin sulfonates, olefin sulfonates, monoglyceride sulfates, sarcosinates and detergents with similar function, preferably in the form salts of alkali metals, for example sodium, may be present, sometimes in partial replacement of the synthetic organic detergents previously mentioned, but in general, their possible presence is added to that of such detergents. Normally, additional detergents are sulfated or sulfonated products (generally in the form of sodium salts) and contain long chain fatty or linear alkyl groups (8 to 20 carbon atoms). In addition to any additional anionic synthetic organic detergents, nonionic and amphoteric materials may also be present, such as Neodol ', sold by Shell Chemical Company, which are condensates of ethylene oxide and fatty alcohols higher, for example Neodol ^ 23-6.5, which is a condensation product of a higher fatty alcohol of about 12 or 13 carbon atoms with about 6.5 moles of ethylene oxide. Examples of the various detergents and classes of detergents mentioned can be found in Surface Active Agents, Vol. Il, de Schwartz, Perry and Berch (Interscience 35 Publishers, 1958).

The combination of adjuvant detergent salts of the present invention which has been found to improve the detergency of the mixture of synthetic anionic organic detergents and to produce the desired pH in the liquid detergent and in the wash water , is a mixture of tripolyphos-05 sodium phate and sodium carbonate. The detergency builder salts are used in the compositions of the present invention in amounts generally of from about 5 to 25% by weight. In the preferred combination of detergency builder salts, sodium XO tripolyphosphate is present in proportions of about 5 to 20%, preferably 10 to 16%, and sodium carbonate is present in an amount of about 1 to 10% by weight, preferably 3 to 7%, the weight ratio of tripolyphosphate to carbonate in the mixtures of preferred detergency builders being from about 2: 1 to 6: 1, and more preferably about 2: 1 to 4: 1. As used herein, the terms "carbonates" or "carbonate" of alkali metal refer to the carbonates, bicarbonates and sesquicarbonates of such alkalinic metals.

In order to achieve the best processing properties, easier mixing and satisfactory end use, it is preferable that the sodium tripolyphosphate has a low content of tripolyphosphate of the Phase I type. Thus, normally, the content of tripolyphosphate of the type Phase I is less than 30% of the tripolyphosphate used. Although in some cases partially neutralized tripolyphosphate may be used, the phosphate used may normally be considered to be pentasodium tripolyphosphate Na5P301Q. Obviously, in certain cases, for example in the presence of potassium salts or other materials, the mutual exchange of ions in an aqueous medium can give salts other than sodium tripolyphosphate, but for the purposes of this specification. , it is considered that the sodium tripolyphosphate, in the form of the pentasodium salt, which is the material normally introduced into the mixer to make the liquid detergent of the invention, is the tripolyphosphate used.

Other pre-fermented detergency 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 and sodium nitrilotriacetate (NTA). Obviously, various mixtures of the mentioned water-soluble builder salts can be used. However, the tripolyphosphate-carbonate mixture described has proved to be the most advantageous, although the other detergency builders and their mixtures are also usable. Other detergency builders which can be used as supplements, in addition to the proportions of the above-mentioned detergency builders, include other phosphates such as tetrasodium pyrophosphate or tetrapotassium pyrophosphate sodium bicarbonate, sodium citrate, glue -20 sodium conate, sodium silicate, and sodium sesqui-carbonate. Among the water-insoluble detergency builders that can be used are zeolites, such as Zeolite A, generally in the form of its crystalline hydrate, although amorphous zeolites may also be useful.

Polyacetal carboxylates are generally described in U.S. Patents 4,144,226 and 4,315,092. U.S. Patent 4,146,495 describes detergent compositions containing polyacetal carboxy lates as detergency builders.

The polyacetalcarboxylates which are useful herein as detergency builders can be considered to be those described in U.S. Patent No. 4,144,226 and can be prepared by the process mentioned therein. An example of such a product is represented by the formula: 11 R1 - (CH0) n “R2

COOM

where M is chosen for an alkali metal, ammonium, 05 alkyl groups of 1 to 4 carbon atoms, tetraalkylammonium groups and alkanolamine groups, the latter two groups having from 1 to 4 carbon atoms in their portions alkyl, n is on average at least 4, and R and R. are chemically stable groups 1-10 which stabilize the polymer against rapid depolymerization in alkaline solution. Preferably, the polyacetal carboxylate is one in which M is an alkali metal, for example sodium, n ranges from 50 to 200, is 15 · CH3CH20 M00Ç HCO- 011 H3C-ÇO-

H3C MOOC

20 or a mixture of these groups, R2 is * 'och2ch3

-CH

ch3 25 and has an average value of 20 to 100, preferably 30 to 80. The calculated weight average molecular weights of the polymers are normally in the range from 2000 to 20,000, preferably from 3,500 to 30,000, and better still from 5000 to 9000, for example around 8000.

A polyacetal-carboxylate of. Particularly preferred sodium is sold by Monsanto Company and is known as Builder U. It has a calculated average molecular weight of about 8000 and an active polymer content of about 80%.

Although the preferred polyacetal carboxylates have been described above, it is obvious that they can be replaced in whole or in part by other polyacetal carboxylates of this type or adjuvant salts of organic detergency appa -05 rents described in the aforementioned patents concerning such compounds, their manufacturing processes and the compositions in which they are used. Also, the chain termination groups described in the various patents can be used, in particular the US patent. A. No. 4 144 226, provided that they have the desired stabilizing properties, which allow the detergency builders mentioned to be depolymerized in acid media, facilitating their biodegradation in waste streams, but maintain their stability in alkaline media, such as washing solutions.

The bentonite used here is a colloidal clay (aluminum silicate) containing montmorillonite. Swelling bentonites are generally characterized as being sodium bentonites, that is to say a bentonite in which the predominant cation is sodium. Among the clays of sodium bentonite type, we prefer, in particular, those of Wyoming (generally designated by bentonite from the western United States of America or from Wyoming).

The bulking power of bentonite is generally associated with its tissue softening properties. In water, the bulking power of sodium bentonite is 3 to 20 milliliters / gram, preferably 7 to 15 ml / gram, and its viscosity, at a concentration of 6% in water, is generally from 3 to 30 mPa.s, preferably from 8 to 30 mPa.s. The preferred swelling bentonites are sold under the trademark HI-JEL by Georgia Kaolin Co. These materials are the same as the bentonites which were previously sold under the trademarks MINERAL COLLOID and THIXO-JEL. These are selectively exploited and enriched bentonites and those which are considered to be the most useful are available under the designations HI-JEL No. 1, 2, 3, etc., corresponding to THIXO-JEL No. 1 "2/3 and 4. These materials have a maximum free moisture content (before addition to the liquid medium) of 4% to 8% and densities of about 2.6. The bentonite XO is preferably a bentonite passing through a 0.074 mm mesh screen, and better still, at least 90% of the particles pass through a 0.044 mm mesh screen, so that the equivalent diameter of bentonite can be considered being less than 74 mi-X5 crometers, and more preferably less than about 44 micrometers.

Typical chemical analyzes of some bentonites which are useful in making the liquid detergents of the invention reveal that they contain from 64.8 to 73.0% of SiO2f from 14 to 18% of Al2O3 from 1.6 to 2.7% MgO, 1.3-3.1 CaO, 2.3-3.4% i ^ O ^, 0.8-2.8% Na2O and 0.4- 7.0 I of K20.

Although bentonites from the western United States of America are preferred, it is also possible to use other bentonites, such as those which can be produced by processing bentonites from Italy or the like containing proportions relatively weak exchangeable monovalent metals (sodium and potassium) with alkaline materials such as sodium carbonate, in order to increase the cation exchange power of these products. It is considered that the Na20 content of the bentonite must be at least, approximately 0.5%, preferably at least 1%, and better still at least 2%, so that the clay is sufficiently gon ~ floating and has good properties softening- ·> 14 tes and dispersants in aqueous suspension. Preferred inflatable bentoni of the types described above are sold under the trademarks Laviosa and Winkelmann, for example Laviosa AGB and Winkelmann 05 <3-13.

Other bentonites which are particularly useful in the liquid detergent compositions of the invention due to their white or very light color include Polarity KB 325 from American 10 Colloid Company, a bentonite from California, and GK 129 from Georgia Kaolin, a bentonite from Mexico.

The viscosity of the liquid detergent of the invention is normally about 1000 to 10,000 mPa.s, preferably 2,000 to 7,000 mPa.s, but products having other suitable viscosities may also be useful. At the viscosity values mentioned, the liquid detergent can be poured, it is stable, does not separate and is uniform. The pH of the liquid detergent suspension, generally from 7 to 11.5, preferably from 8 to 10.5, seems to favor the maintenance of the stability of the product and its ability to be poured.

The following nonlimiting examples illustrate the invention. Unless otherwise indicated, all parts are expressed by weight and temperatures in ° C.

EXAMPLE 1

Components Percent

Pentasodium tripolyphosphate 11.0 30 Bentonite (Georgia-Kaolin 129) 12.0

Sodium carbonate 2.0

Sodium sesquicarbonate 2.0 (Linear tridecyl) sodium benzenesulfonate 8.0 35 AEOS (l) 3.0

Carboxymethylcellulose (CMC) 0.2

Optical brightening agent 0.3 15

Perfume 0/4

Enzyme (Esperase 8.OE) 1.0 Glycerin 3.0

Borax 2.5 05 Citric acid 2.0

Water and additives the rest.

(1) Sodium alkyl polyethoxy sulfate in which the alkyl group has from 12 to 15 carbon atoms 10 and the polyethoxy chain has 3 ethoxy groups.

(2) "Esperase", sold by Novo Industries with an activity of 8.0 KNPU / g (Kilo-units of protease

Novo / g).

The composition indicated above is prepared by the following procedure: 30.0 parts of deionized water at 4.4 ° C. are added to a suitable mixing device such as a vertical cylindrical tank equipped with an agitator. By setting the agitator to a medium degree of agitation, a mixture consisting of 2.0 parts of anhydrous sodium carbonate, 2.0 parts of sodium sesquicarbonate and 0.2 parts of sodium carboxymethyl cellulose is incorporated into the mixture. 'water. The agitator speed is then increased to a maximum value and 11.0 parts of pentasodium tripolyphosphate and 12.0 parts of bentonite are slowly added to the mixing apparatus over a period of 10 to 15 minutes to form a suspension dirty white. The stirring speed is then reduced to a slow / medium value while adding 8.64 parts of an LTBS suspension with a high content (about 50%) of IA (active ingredient). The solution of optical brightener and dye consisting of 0.3 part Tinopal LMS-X (CIBA-GEIGY), 0.99 part blue dye and 4.02 parts deionized water is then added. As soon as a homogeneous bluish green solution is obtained, 0.4 part of perfume is added to the mixture with stirring. Then, 3.0 parts of glycerin and 2.5 parts of borax are slowly added in the form of a two-component suspension. Stirring is continued until the mixture is homogeneous in appearance, then 2.0 parts of citric acid and 9.0 parts of water are slowly added. The stirring of the mixture is then reduced, while adding 10.95 parts of a detergent base of mixed active ingredients consisting of a suspension LTBS (approximately 30% AI) and AEOS (approximately 27.5% IA). Then 1.0 part of proteolytic enzyme is added slowly while continuing to agitate until all of the materials are completely dispersed or dissolved.

EXAMPLE 2 The reinforced liquid detergent compositions A to G containing enzymes are formulated as indicated below in Table 1. The percentages indicated are expressed in percent by weight. The arrows are used to indicate the extent to which Compositions B to G are identical to Composition A.

TABLE I

Components A B C D Ξ F G

Pentasodium tripolyphosphate 11.0 25 Bentonite (Georgia-Kaolin 129) 12.0

Sodium carbonate 2.0

Sodium sesquicarbonate 2.0 (Linear tridecyl) benzene-sodium tallow onate 8.0 30 AE0S (1) 3.0

Optical brightening agent (Tinopal LMS-X) 0.3

Perfume 0.4 CMC 0.2 35 Enzyme ^ 1.0 V / ν 'v V V ^

Glycerin - 3.0-3.0-- -3.0

Borax - -2.5 2.5 -2.5 2.5 17

Carboxylic acid type compound - - 2/0 2.0 2.0

Water and additives -------- the rest ----— 05 (1) Sodium alkyl-polyethbxy-sulfate in which the alkyl group has 12 to 15 carbon atoms and the polyethoxy chain has 3 ethoxy groups , (2) "Esperase" sold by Novo Industries with an activity of 8.0 KNPU / g.

The enzymatic activities of Compositions A to F are tested after 7 days of storage at 43 ° C. The enzymatic activity measured for each composition after this storage period is indicated in Table II as a percentage of the initial value. The various carboxylic acids and salts used in the formulas of Compositions A, B, C, D, E and G are indicated in Table II, as well as the enzymatic activity corresponding to each composition.

20 TABLE II

ENZYMATIC STABILITY

Composition Percent of enzymatic activity at the end

__________7 days at 43 ° C

25 A (Witness) ND *

B (with glycerin) ND

C (with borax) ND

D (with glycerin and borax) 50

Composition E (with compound of carboxylic acid type) the compound of carboxylic acid type being one of the following:

(1) ND succinic acid

(2) Malonic acid "(3) Malic acid" 35 (4) Tartaric acid "(5) Aspartic acid" (6) Citric acid "* to 18 (7) · Sodium tartrate" (8) Sodium citrate 11 * ND - not detectable (less than 10% of residual activity-05 le)

Composition G (with glycerin / borax / Percentage of compound of carboxylic acid type), enzymatic after compound of carboxylic acid type - 7 days at 43 ° C

10 that being one of the following: .......

(1) Succinic acid 70 (2) Malonic acid 70 (3) Malic acid 78 (4) Tartaric acid 73 15 (5) Aspartic acid 90 (6) Citric acid 74 (7) Sodium tarträte 66 (8) Sodium citrate 52 20 As can be seen from Table II, Com position A, the control composition, as well as Compositions B and C which contain glycerin and borax, as respective individual stabilizers, show almost no enzymatic activity at 25 end of the. 7 day storage period at 43 ° C.

Since enzyme activities below 10% cannot be measured accurately, they are referred to as "ND". Composition D containing glycerin / borax in the absence of a carboxylic acid type compound shows an improvement in enzymatic stability compared to Composition A, but approximately 50% of the enzyme is deactivated. The various Compositions E containing various compounds of the carboxylic acid type as indicated show absolutely no improvement in the enzymatic stability with respect to Composition A. However, the Compositions G formulated according to the invention exhibit the unexpected and synergistic improvement of enzymatic stability, which is obtained by using a combination of glycerin / borax and a carboxylic acid compound in the liquid detergent compositions of the invention. It is noted that each of the compositions corresponding to Composition G shows a clear increase in the enzymatic activity compared to Composition D (containing glycerin and borax).

A comparison of the enzymatic activity obtained with Compositions D (glycerin / borax) and the various Compositions F (borax / compound of carboxylic acid type) and G (formulated according to the invention) is indicated below in Table III.

15

TABLE III

Composition Percentage of activity

enzymatic after 7 days at 43 ° C

20 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 25 F (borax / acid citric) 42 G (glycerin / borax / citric acid) 74 ND = not detectable (residual activity less than 10%).

As shown in Table III, the various its Compositions G containing a three-component stabilizing system according to the invention offer a synergistic improvement in the enzymatic stability compared to Compositions D and F formulated according to the prior art.

Claims (22)

1. Reinforced liquid stabilized detergent composition containing enzymes and fabric softener, characterized in that it comprises: 05 (a) approximately 5 to 20% by weight of one or more detergent surfactant compounds chosen from anionic detergent compounds , non-ionic and ampho-teres; (b) about 5 to 30% by weight of one or more adjuvant detergency salts chosen from tripolyphosphates of alkali metals, carbonates of alkali metals, nitrilotfiaciacetates of alkali metals and polyacetal carboxylates? (c) about 5 to 20% by weight of a swelling clay of the bentonite type; (d) an effective amount of an enzyme or a mixture of enzymes chosen from alkaline enzymes of the protease and alpha-amylase type; (e) an enzyme stabilization system containing, based on the weight of the detergent composition, (i) about 1 to 10% glycerin; (ii) about 1 to 8% of a boron compound selected from boric acid, boric oxide and alkali metal borates and (iii) about 0.5 to 8% of an acid type compound carboxylic chosen from mono-, di- and / or polycarboxylic acids of 1 to 8 carbon atoms and their water-soluble salts; and (f) the remainder consisting of water and optionally of perfume and other additives. 30 2. Liquid detergent composition according to claim 1, characterized in that it comprises: (a) about 5 to 15% of an alkali metal alkylbenzene sulfonate in which the alkyl group has from 12 to 15 carbon atoms; (B) about 0.5 to 5% of an alkali metal alkyl polyethoxy sulphate in which the alkyl group has from 10 to 18 carbon atoms and the polyethoxy chain has from 3 to 11 ethylene oxide groups, the weight ratio of (a) to (b) being from about 2: 1 to about 6: 1; (c) about 5 to 20% sodium tripolyphosphate (d) about 1 to 10% sodium carbonate, sodium bicarbonate or a mixture thereof, the weight ratio of (c) â (d) being from about 2: 1 to about 6: 1; (E) about 10 to 15% of a sodium bentonite; (f) an effective amount of said enzyme or mixture of enzymes? (g) the enzyme stabilizing system containing, based on the weight of the detergent composition, (i) about 1 to 5% glycerin? (ii) about 1 to 5 of an alkali metal borate and (iii) about 0.5 to 4% of said carboxylic acid compound; and (h) the remainder consisting of water and optionally 20 minor additives. 3. A liquid detergent composition according to claim 2, characterized in that the alkali metal alkylbenzene-sulfonate is sodium (tridecyl linai'-re) benzene sulfonate and the alkali metal alkylpolyethoxy sulfate is a sulfate of this type in which the alkali metal is sodium, the alkyl group contains from 12 to 15 carbon atoms and the polyethoxy chain has about 3 ethylene oxide groups. 4. Liquid detergent composition according to "claim 3, characterized in that the ratio of tridecylbenzene sulfonate to polyethoxysulfate is from about 2: 1 to about 4: 1. 5. Liquid detergent composition according to claim 2, characterized in that the boron compound is an alkali metal borate. 6. Liquid detergent composition according to I "22" claim 5, characterized in that the borate is borax- 7. Liquid detergent composition according to claim 2, characterized in that it contains 05 approximately 8 to 16% of sodium tripolyphosphate and approximately 2 to 6 I of sodium carbonate, sodium bicarbonate or their mixtures. 8. A liquid detergent composition according to claim 2, characterized in that the compound 10 of carboxylic acid type is aspartic acid or a water-soluble salt of this acid. 9. Liquid detergent composition according to claim 2, characterized in that the carboxylic acid type compound is tartaric acid or a water-soluble salt of this acid. 10. Liquid detergent composition according to claim 2, characterized in that the carboxylic acid type compound is citric acid or a water-soluble salt of this acid. 11. Liquid detergent composition according to claim 2, characterized in that the compound of carboxylic acid type is malonic acid or a water-soluble salt of this acid. 12. Liquid detergent composition according to claim 2, characterized in that the carboxylic acid type compound is malic acid or a water-soluble salt of this acid. 13. A laundering process, characterized in that it consists in bringing the stained and / or soiled fabrics to be washed in contact with a stabilized reinforced liquid detergent composition containing enzymes, comprising: (a) approximately 5 to 20% by weight of one or more surfactant detergent compounds selected from 35 anionic, nonionic and am-photeric detergent compounds (b) approximately 5 to 30% by weight of one or more adjuvant detergency salts chosen from tripolyphosphates of alkali metals, carbonates of alkali metals, nitrilotriacetates of alkali metals and polyacetal carboxylates; 05 (c) about 5 to 20% by weight of a swelling clay of the bentonite type; (d) an effective amount of an enzyme or a mixture of enzymes chosen from alkaline enzymes of the protease and alpha-amylase type? (E) an enzyme stabilization system containing, based on the weight of the detergent composition (i) about 1 to 10% glycerin, (ii) about 1 to 8% of a boron compound selected from boric acid, boric oxide, and alkali metal borates; And (iii) about 0.5 to 8% of a compound of carboxylic acid type chosen from mono-, di- and / or polycarboxylic acids of 1 to 8 carbon atoms and their water-soluble salts; and (f) the remainder consisting of water and optionally 20 of perfume and other additives. 14. The method of claim 13, characterized in that the liquid detergent composition comprises: (a) about 5 to 15% of an alkali metal alkylbenzene sulfonate in which the alkyl group has 12 to 15 carbon atoms ; (b) about 0.5 to 5% of an alkali metal alkyl polyethoxy sulfa in which the alkyl group has from 10 to 18 carbon atoms and the polyethoxy chain has from 3 to 11 oxide groups. ethylene, the weight ratio of (a) to (b) being from about 2: 1 to about 6: 1. (c) about 5 to 20% of sodium tripolyphosphate? (D) about 1 to 10% sodium carbonate; sodium bicarbonate or mixtures thereof, the weight ratio of (c) to (d) being about 2: 1 to t 24 about 6: 1, (e) about 10 to 15% of a sodium bentonite ; (f) an effective amount of said enzyme or said mixture of enzymes; 05 (g) the enzyme stabilization system containing, on the basis of the weight of the detergent * composition, (i) about 1 5 5% of glycerin, (ii) about 1 to 5% of a borate alkali metal and (iii) about 0.5 to 4% of said carboxylic acid type compound; and (h) the remainder consisting of water and possibly minor additives. 15. The method of claim 14, characterized in that the alkali metal alkylbenzene sulfonate is sodium (linear tridecyl) benzene sulfonate and the alkali metal alkylpolyethoxy sulfate is a sulfate of this type. the type in which the alkali metal is sodium, the alkyl group has 12 to 15 carbon atoms and the polyethoxy chain has about 3 ethylene oxide groups. 16. The method of claim 15, characterized in that the ratio of tridecylbenzene sulfonate to polyethoxy sulfate is from about 2: 1 to about 4: 1. 17. The method of claim 14, characterized in that the boron compound is borax. 18. Method according to claim 14, characterized in that the liquid detergent composition contains approximately 8 to 16% of sodium tripolyphosphate and approximately 2 to 6% of sodium carbonate, sodium bicarbonate or their mixtures, 19. The method of claim 14, characterized in that the carbo-xylic acid compound is aspartic acid or a water-soluble salt of this acid. 20. The method of claim 14, characterized in that the compound of carbo-xylic acid is citric acid or a water-soluble salt of this acid. 21. Method according to claim 14, characterized in that the carboxylic acid type compound is italic acid or a water-soluble salt of this acid. 22. The method of claim 14, characterized in that the carboxylic acid compound is malonic acid or a water-soluble salt of this acid. 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