DK159881B - BUILDER-CONTAINING Single-phase Liquid Anionic Detergent Containing Stabilized Enzymes - Google Patents

Description

DK 159881B

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The present invention relates to stable, builder-containing, enzyme-containing, liquid detergents suitable for detergents and softeners. More particularly, the invention relates to aqueous, enzyme-containing liquid detergent agents which contain a non-phosphate-containing detergent builder and which are distinguished by being physically stable, clear, single-phase, homogeneous liquid agents.

The formulation of stabilized enzyme-containing and liquid detergents has been the subject of much attention in the prior art. Preferably, the desirability of incorporating enzymes into detergent agents is due to the fact that proteolytic and amylolitic enzymes are able to efficiently decompose proteinaceous and starchy substances found on soiled textile fabrics, thereby removing stains such as sauce stains, blood stains, chocolate stains and the like are easier to wash. However, enzymatic agents suitable for detergents, especially proteolytic enzymes, are relatively expensive. In fact, they are generally the most expensive component of a typically liquid detergent, even when contained in relatively small quantities. In addition, enzymes are known to be unstable in aqueous agents. It is for this reason that an excess of enzymes in liquid detergent agents are generally required to compensate for the expected loss of enzyme activity upon storage for extended periods. Thus, in the prior art, there are numerous proposals for stabilizing enzyme-containing liquid detergent agents and especially non-builder-containing liquid agents using various substances which are incorporated into the agent and serve as enzyme stabilizers.

In the case of liquid detergent containing a builder, the problem of enzyme stability is particularly acute.

This is primarily because detergent builders have a destabilizing 2

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inhibitory effect on enzymes, even in agents containing enzyme stabilizers that are otherwise effective in non-builder-containing formulations. Furthermore, the incorporation of a builder into a liquid detergent agent presents a further problem, namely the ability to form a stable, single-phase solution, e.g. the solubility of tripolyphosphate becomes relatively limited in aqueous agents and especially in the presence of anion-active and nonionic detergents. Thus, in GB Patent Application No. 2,079,305, published January 20, 1982, f.

10, for example, describes an aqueous, builder-containing, enzyme-containing liquid detergent stabilized by a mixture of polyol and boric acid. However, the agents described in the examples, rather than being stable, clear, single-phase solutions, are rather vague suspensions that tend to separate by storage over extended periods. Thus, the problems of enzyme stability and physical product stability remain a problem to be solved by formulating a commercial, acceptable, builder-containing, enzyme-containing liquid detergent.

The present invention provides a stable, aqueous, builder-containing, clear, single-phase, enzyme-containing liquid detergent comprising (a) from 8 to 20% by weight of one or more surface active, anionic surfactants (or detergent compounds), 25 (b) from 5 to 25% by weight of a water-soluble non-phosphate-containing detergent builder salt; (c) an effective amount of an enzyme or enzyme mixture selected from alkaline protease enzymes and α-amylase enzymes;

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(d) an enzyme stabilizing system, based on the weight of the detergent, contains (i) from about 12 to 25% propylene glycol and (ii) from 1 to 5% of a boron compound selected from the group consisting of boric acid, boron oxide and alkali metal borates, and 5 (e) from ca. 25 to 75% by weight water.

Using the agent of the invention, the washing of stained and / or soiled substances is accomplished by contacting such substances with an aqueous solution of the aforementioned liquid detergent agent. In contrast to enzyme-containing detergent agents known in the art, the compositions of the invention are characterized by being clear, single-phase, homogeneous solutions which are physically stable upon storage for extended periods and within a wide temperature range. In order to avoid product separation, the present agents are preferably substantially free of a phosphate builder salt content.

In contrast to the enzyme-containing, builder-containing, liquid, anionic detergent agents described in the art, the anion-active surfactant in the agents is made soluble in the presence of a builder salt. In addition, the present enzyme-containing agents are distinguished by the presence of an enzyme stabilizing system which, in addition to making the enzyme long-term stable over a wide temperature range, serves to increase the solubility of the anionic surfactant and the non-phosphate-containing builder in the aqueous agent. so as to form a physically stable, single-phase solution for the particular range of agents indicated.

The enzyme stabilizing system according to the invention is a mixture of propylene glycol and a boron compound selected from boric acid, boron oxide and alkali metal borate which is capable of reacting with propylene glycol. The amount of propylene glycol is from 12 to 25%, preferably from 15 to 20% by weight, and the amount of the boron compound can vary from 1 to 5%, preferably 4

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from 1 to 3% by weight of the agent.

The alkaline proteolytic enzymes suitable for the present compositions comprise the various commercial liquid enzyme preparations which have been adapted for use in detergent agents, although powder formulations can also be used, although it is generally so. that they are less suitable for incorporation into the builder-containing liquid detergent agents. Suitable liquid enzyme preparations thus include "Alcalase?" C> g "Esperase" ® 10 sold by Novo Industries, Copenhagen, Denmark, and "Maxa-tase" and "AZ-Protease sold by Gist-Brocades, Delft, The Netherlands. Esperase ™ is particularly preferred for the present agent because of its optimized activity at the higher pH values corresponding to builder-containing detergent agents.

15 Among the suitable liquid α-amylase enzyme preparations are those sold by Novo Industries and Gist-Brocades jd?) Under the trade name "Thermamyl" and the trade name "Maxamyl1®", respectively.

The synthetic anionic detergent used in the practice of the invention may be any of a wide variety of compounds of this kind which are well known and detailed in the text Surface Active Agents, vol.II, by Schwartz, Perry & Berch, published in 1958 by Interscience Publishers, the mention of these detergents being considered as incorporated in the present text.

The most preferred anionic detergent compounds are the higher (10-18 or 20 carbon atoms) alkylbenzenesulfonate salts, wherein the alkyl group preferably contains 10-15 carbon atoms, preferably being a straight chain alkyl group of 12 or 30 carbon atoms. Such an alkylbenzene sulfonate preferably has 5

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show a high content of 3- (or higher) phenyl isomers and a correspondingly low content (usually slightly below 50%) of 2- (or lower) phenyl isomers. In other words, the benzene ring is, for the most part, bound at the 3-, 4-, 5-, 6- or 5-position of the alkyl group, and the content of isomers in which the benzene ring is bonded at the 1- or 2-position is relatively low. Typical alkylbenzene sulfonate surfactants are described in U.S. Patent No. 3,320,174. Of course, more heavily branched alkylbenzenesulfonates may also be used, but these are usually not preferred due to their lack of biodegradability.

Other anionic detergents which are suitable are the olefin sulphate salts. These generally contain long chain alkenyl sulfonates or long chain hydroxyalkanesulfonates (where OH is on the carbon atom which is not directly bonded to the carbon atom bearing the -SOgH group). The olefin sulfonate detergent usually comprises a mixture of compounds of this type in varying amounts, often together with long chain disulfonates and sulfate sulfonates. Such olefin sulfonates 20 are disclosed in patents such as U.S. Pat. No. 2,061,618, No. 3,409,637, No. 3,332,880, No. 3,420,875, No. 3,428,654, and 3,506,580, and GB-PS. No. 1,129,158. The number of carbon atoms in the olefin sulfonate is usually in the range of 10 to 25, more commonly 10 to 18 or 20, e.g. preferably a mixture of C 1, C 4 and C 6 with an average of approx.

14 carbon atoms or a mixture preferably of C 14, C 16 carbon atoms.

Another class of useful anionic detergents is the class of higher paraffin sulfonates. These may be primary paraffin sulfonates prepared by reaction of long chain α-olefins and bisulfites, e.g. sodium bisulfite, or paraffin sulfonates with the sulfonate groups distributed along the paraffin chain, such as the products prepared by reaction of a long chain 6

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paraffin with sulfur dioxide and oxygen under ultraviolet light, followed by neutralization with sodium hydroxide or other suitable base (such as U.S. Pat. No. 2,503,280, No. 2,507,088, No. 3,260,741, and 3,372,188; PS No. 735,096).

The paraffin sulfonates preferably contain from 13 to 17 carbon atoms and will normally be the monosulfonate, but if desired, they may be di-, tri- or higher sulfonates. The di- and poly-sulfonates will typically be used in admixture with a corresponding monosulfonate, e.g. as a mixture of mono- and di-sulfonates containing up to ca. 30% of the disulfonate. The hydrocarbon substituent thereof is preferably linear, but if desired, branched paraffin sulfonates may be used, although they are poorer in biodegradability.

Other suitable anionic detergents are sulfated, ethoxylated 15 higher fatty alcohols of the formula RO ^H ^O )SO ^M wherein R is a fatty alkyl of 10-18 or 20 carbon atoms, m is from 2 to 6 or 8 (preferably having a value of about 1/5 to 1/2 of the number of the carbon atoms in R) and M is a solubilizing salt-forming cation such as, an alkali metal, ammonium, lower alkyl-20 amino or lower alkanolamino, or a higher alkylbenzene sulfonate wherein the higher alkyl moiety has 10 to 15 carbon atoms.

Ethylene oxide is the preferred lower alkylene oxide of the anion-active alkoxylate detergent, and the amount thereof in the polyethoxylated higher alkanol sulfate is preferably 2 to 5 moles of ethylene oxide groups found per liter. 3 moles are most preferred, especially when the higher alkanol has 11 or 12 to 15 carbon atoms. In order to maintain the desired hydrophilic-lipophilic equilibrium when the carbon atom content of the alkyl chain is in the lower range of 10 to 18 carbon atoms, the 30 ethylene oxide content of the detergent can be reduced to approx.

2 moles per moles, whereas when the higher alkanol has 16 - 18 carbon atoms in the higher range, the number of 7

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ethylene oxide groups may be increased to 4 or 5 and in some cases to as much as 8 or 9. Similarly, the salt-forming cation may be altered to obtain the best solubility. It may be any suitable solubilizing metal or radical, but will most often be an alkali metal, e.g. sodium, or ammonium. If lower alkylamine or alkanolamine groups are used, the alkyl groups and alkanol groups will usually contain from 1 to 4 carbon atoms, and the amines and alkanolamines may be mono-, di- and tri-substituted as in monoethanolamine, diisopropanolamine and trimethylamine.

The poly-lower alkoxy-higher alkanol sulfates can be used in combination with other preferred anionic detergents, such as the higher alkylbenzenesulfonates, to obtain optimum purification action in the present builder-containing liquid detergent agents. A preferred polyethoxylated alcohol sulfate detergent can be obtained from Shell Chemical Company and marketed as "Neodol" 25-3S.

Examples of the higher alcohol polyethene oxy sulphates which may be used in the liquid detergent compositions of the invention include: Mixed C 12 -J 4 normal or primarily alkyl triethene oxy sulphate, sodium salt; myristyl triethenoxy sulfate, potassium salt; n-decyldiethene oxysulfate, diethanolamine salt; lauryl diethoxy sulfate, ammonium salt; palmityltetraethenoxysulfate, sodium salt; 25 usually mixed primarily alkyl-mixed tri- and tetra-ethenoxy sulfate, sodium salt; stearyl pentaethenoxy sulfate, trimethylamine salt; and usually mixed primarily alkyl triethenoxysulfate, potassium salt.

Other suitable anionic detergents include the higher acyl sarcosinates, e.g. sodium N-lauroylsarcosinate, higher fatty alcohol sulphates such as sodium lauryl sulphate and sodium talgal sulphate, sulphated oils, sulphates of mono- and diglycerides of 8

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higher fatty acids, e.g. stearine monoglyceride monosulfate (although the higher sodium alcohol sulfates thereof have been found to be inferior to the polyethoxylated sulfates in purity), aromatic poly (lower alkenoxy) ether sulfates such as the sulfates of the condensation products of ethylene oxide and nonyl phenol (usually with 1-20 oxyethylene groups per molecule, preferably 2-12), polyethoxy higher alcohol sulfates, and alkylphenol polyethoxy sulfates having a lower alkoxy substituent (having 1-4 carbon atoms, e.g. methoxy) on a carbon atom near 10 at that bearing the sulfate group such as the monomethyl ether monosulfate of a long-chain vicinal glycol, e.g. a mixture of vicinal alkanediols having 16-20 carbon atoms in a straight chain, acyl esters of isethionic acid, e.g. oleylisethionates, acyl-N-methyltaurides, e.g. potassium N-methyllauroyl or oleyl taurides, higher alkylphenyl polyethoxysulfonates, higher alkylphenyl polyethoxysulfonates, higher alkylphenyl disulfonates, e.g. pentadecylphenyl disulfonate, and higher fatty acid soaps, e.g. mixed coconut oil and tallow soaps in a 1: 4 ratio.

Of the aforementioned types of anionic detergents, the sulfates and sulfonates are usually preferred, but the corresponding organic phosphates and phosphonates may also be used when their phosphorus content is not unfortunate. Generally, the water-soluble, anionic, synthetic, organic detergents (including soaps) are salts of alkali metal cations, e.g.

Of potassium, lithium and, especially, sodium, although salts of ammonium and substituted ammonium cations, such as those previously described, e.g. triethanolamine and triisopropylamine can also be used.

Optionally, a nonionic detergent may be used in smaller amounts to supplement the anionic detergent compound in the present builder-containing liquid detergent agents. When used in combination with an anionic detergent, the amount of nonionic detergent will generally be below about 10% 9

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and preferably below ca. 5% by weight of the total agent.

The nonionic detergents are usually poly lower alkoxylated lipophilic compounds wherein the desired hydrophilic lipophilic equilibrium is obtained by adding a hydrophilic poly lower alkoxy group to a lipophilic moiety. For the present agents, the nonionic detergent used is preferably a poly lower alkoxylated higher alkanol wherein the alkanol has 10 to 18 carbon atoms and wherein the number of moles of lower alkylene oxide (with 2 or 3 carbon atoms) is from 3 to 12 Of such substances, it is preferred to use those substances in which the higher alkanol is a higher fatty alcohol having 11 or 12 to 15 carbon atoms and containing from 5 to 8 or 5-9 lower alkoxy groups per liter. moth. The lower alkoxy group is preferably ethoxy, but it may in some cases, if desired, be admixed with propoxy, the latter, if included, is usually a side component (below 50%). Examples of such compounds are those compounds in which the alkanol has 12 to 15 carbon atoms and contains approx. 7 ethylene oxide groups per moles, e.g. Neodol 25-7 and Neodol 23-6.5, which products are manufactured by Shell Chemical Company, Inc. The former is a condensation product of a mixture of higher fatty alcohols with an average of approx. 12 to 15 carbon atoms with approx. 7 moles of ethylene oxide, and the latter is a similar mixture in which the carbon atom content of the higher fatty alcohol is 12 - 13, 25 and the number of ethylene oxide groups per liter is higher. mole on average is approx.

6.5. The higher alcohols are primary alkanols. Other examples (Ok pier of such detergents include Tergitol 15-S-7 and Tergitol® 15-S-9, both of which are linear secondary alcohol ethoxylates manufactured by Union Carbide Corporation. The former is a mixed ethoxylation product of 11-15 carbon atomic linear linear secondary alkanol with 7 moles of ethylene oxide, the latter being a similar product, but reacting 9 moles of ethylene oxide.

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Also useful in the present compositions are high molecular weight, nonionic compounds, e.g. "Neodol" 45-11, which are similar ethylene oxide condensation products of higher fatty alcohols, the higher fat alcohol having 14-15 carbon atoms, and the number of ethylene oxide groups per liter. mole is approx. 11. Such products are also manufactured by Shell Chemical Company. Other useful nonionic compounds are represented by "Plurafac" B-26 (BASF Chemical Company), which is a reaction product of a higher linear alcohol and a mixture of ethylene and propylene oxide.

In the preferred poly-lower alkoxylated higher alkanols, the best equilibrium between hydrophilic and lipophilic moieties is obtained when the number of lower alkoxy groups is from approx. 40 to 100% of the number of carbon atoms in the higher alcohol, preferably 40 to 50% thereof. The nonionic detergent preferably consists of at least 50% of the preferred ethoxylated alkanols. High molecular weight alkanols and various other, usually solid, nonionic detergent compounds and surfactants can contribute to the gelation of the liquid detergent and are therefore normally omitted or included in the present amount, although minor amounts thereof may be used due to of their purifying properties, etc. With respect to both preferred and less preferred nonionic detergents, the alkyl groups present therein are preferably linear, although a minor degree of low branching can be tolerated, such as at a carbon atom adjacent to or two carbon atoms. away from the terminal carbon atom of the straight chain and away from the ethoxy chain, provided that such branched alkyl has a length of not more than 3 carbon atoms. Usually, the amount of carbon atoms in such a branched configuration is low and rarely exceeds 20% of the total carbon atom content of the alkyl group. Although linear alkyl groups, which are ultimately linked to the ethylene oxide chains, are highly preferred and believed to result in the optimal combination of purity, biodegradability and non-gelling properties,

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11 the medial or secondary connection to the ethylene oxide in the chain.

In such cases, these alkyl groups are found only in smaller amounts, usually below 20%, but as in the case of the aforementioned "Tergitols", the amount may be greater. Also, when 5 propylene oxide is included in the lower alkylene oxide chain, it will usually be less than 20% thereof and preferably below 10% thereof.

The non-phosphate-containing detergent builder salts are used in the present compositions in amounts generally from about 5 to 25% 10 and preferably from ca. 10 to 20% by weight. Specific examples of non-phosphorus-containing, water-soluble, inorganic builders include water-soluble, inorganic carbonates, bicarbonates and silicates. Alkali metal, e.g. sodium and potassium carbonates, bicarbonates and silicates are particularly suitable herein.

Water-soluble organic builders are also suitable and include alkali metal, ammonium and substituted ammonium polyacetates, carboxylates, polycarboxylates and polyhydroxy sulfonates. Specific examples of polyacetate and polycarboxylate builders include sodium, potassium, lithium, ammonium and substituted ammonium salts of ethylenediaminetetraacetic acid, nitrilotriacetic acid, benzene polycarboxylic acids (i.e., penta and tetraacetic acid,

The percentage of water, the main solvent in the present compositions, is from 25 to 75%, preferably 40 to 60% by weight of the liquid liquid.

The optical fluorescent bleaches or whitening agents used in the liquid detergents are important constituents of modern detergents that give freshly washed clothes and fabrics a clear appearance so that the laundry is not only clean but also looks clean. Although it is possible to use a single optical bleach for a particular purpose in

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In the present liquid detergent compositions, it is generally desirable to use blends of optical bleaches which will have a good clarifying effect on cotton, nylons, polyesters and mixtures of such fabrics and which are also bleach stable. A good description of such optical bleach types is given in the article "The Requirements of Present Day Detergent Fluorescent Whitening Agents" by A.E.Siegrist, J.Am.Oil Chemists Soc., January 1978 (vol.55). This article and U.S. Patent No. 3,812,041, both of which are to be incorporated in the present text, contain detailed descriptions of a wide variety of suitable optical bleaches.

Among the bleaching agents useful in the present liquid detergent agents are: "Calcofluor" 5BM (American Cyanamide), "Calcofluor" White ALF (American Cyanamide), "SOF" A-15 2001 (Ciba), CDW (Hilton-Davis) , "Phorwite" RKH, "Phorwite" BBH, and "Phorwite" BHC (Verona), SCL, Powder, Acid (American Cyanamid), FB 766 (Verona), "Blancophor" PD (GAF), UNPA (Geigy), "Tinopal "BBS 200 (Geigy).

Adjuvants may also be included in the liquid detergent agents 20 to impart additional properties, either functional or aesthetic. The auxiliaries useful include dirt suspending or anti-re-precipitating agents such as polyvinyl alcohol, sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose; thickeners, e.g. gums, alginates, agar-agar; foam enhancers, e.g. laurine myristine diethanolamide; antifoaming agents, e.g. silicones; bactericides, e.g. tribromosalicylanilide, hexachlorophen; dyes; pigments (water dispersible); preservatives; absorbents for ultraviolet light; fabric softeners; clouding agents, e.g. polystyrensuspensioner; and perfumes. Such substances will, of course, be selected for the desired properties of the finished product as well as the compatibility with the other components and their solubility 13

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in the liquid medium.

The present liquid agents are effective and easy to use. Compared to powerful detergent washing powders, much smaller volumes of the present 5 liquids are used to achieve similar cleaning of soiled laundry. For example, when using a typically preferred product of the present invention, e.g. only approx. 132 g or 1/2 cup of liquid for a top-loading automatic washing machine of the type filled above, in which the water volume is 55 - 75 10 liters, and even less is required for one. front-loading washer type. Thus, the concentration of the liquid detergent in the wash water is of the order of approx. 0.2%. The amount of the liquid in the washing solution will usually vary from approx. 0.05 to 0.3%, preferably from 0.15 to 0.25%. The amounts of the various constituents of the liquid agent may vary accordingly. Similar results can be obtained by using larger quantities of a more diluted formulation, but the larger quantity required will incur additional packaging costs and will generally be less convenient for consumers.

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EXAMPLE 1.

Enzyme-containing builder-containing liquid detergents A - E were formulated as given in Table 1. The 5 percentages indicated are weight percentages.

TABLE 1.

A B C D E

Sodium dodecylbenzenesulfonate 7% 7% 7% 7% 7% Ethoxylated C C-C ^ alcohol sulfate (3 moles EO / mole of alcohol) 1 7 7 7 7 7

Optical Bleach 0.2 0.2 0.2 0.2 0.2 0.2

Sodium nitrilotriacetate 15 15 15 15 15 15 PBB2 3 11111

Perfume 0.3 0.3 0.3 0.3 0.3

Protease enzyme ^ 11111

Propylene Glycol - 20 20 20 20

Borax - - 1 2 3 20 h ^ O residue -----------% active enzyme after (a) 4 days at 43 ° C approx (110 ° F) - 98% (b) 6 days at 43 ° C approximately (110 ° F) 0 15 61 86 88 "Neodol" 25-3S sold 25 by Shell Oil Company.

2 "Polar Brilliant Blue" - 1% active color solution.

3 "Esperase" sold by Novo Industries containing 5% enzyme, 75% propylene glycol and the residue H 2 O with an activity 30 of 8.0 KNPU / g (kg Novo protease units / g).

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The enzyme activities of agents A - E were investigated after 6 days of storage at about 43 ° C (110¾1), the percent activity relative to the initial value being given in Table 1. Activity after 4 days was measured exclusively for agent E.

Agents A and B were the only agents which did not contain an enzyme stabilizing system according to the invention and showed a complete (agent A) or almost complete (agent B) loss of enzyme activity after 6 days. Agents C, D and E reflect the pronounced improvement in enzyme stability, 10 which results from the inclusion of propylene glycol and borax in the detergent agent.

Agents B - E were all clear, single-phase, homogeneous solutions that retained their physical stability and clarity after 6 months of storage at both room temperature and about 43 ° C (110 ° F). Agent A, which did not conform to the invention , was physically unstable due to the absence of propylene glycol which, in addition to serving as an enzyme stabilizer (in conjunction with the aforementioned boron compound), promotes the solubility of the anionic detergents and the NTA builder in the aqueous medium.

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EXAMPLE 2.

Enzyme-containing builder-containing liquid detergents F and G were formulated essentially in a similar manner to agents A - E, except that sodium citrate was used as the builder salt instead of sodium NTA. The funds are shown in Table 2 below.

TABLE 2.

F G

Sodium dodecylbenzenesulfonate 7% 7%

Ethoxylated C ^-C ^ alcohol sulfate (3 moles of RO / mole of alcohol) 7 7

Optical Bleach 0.2 0.2 15 Sodium Citrate 12 12 PBBi; L) 1 1

Perfume 0.3 0.3 C2)

Protease Enzyme 11

Propylene glycol 20 20 2 0 Borax - 2 h 2 O ---- the residue ----% active enzyme after 4 days at 43 ° C approx. (110oF) 20% 95% 1 2 "Polar Brilliant Blue" - 25 a 1% active color solution.

2 "Esperase" sold by Novo Industries containing 5% enzyme, 75% propylene glycol and the residue H 2 O with an activity of 8.0 KNPU / g (kilogram Novo protease units / g).

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Agent G of the invention showed an enzyme activity after 4 days of 95% compared to Agent F, which did not contain boron compound and consequently lost more than 3/4 of the original enzyme activity.

Both agents were clear, single-phase solutions that remained physically stable after 6 months of storage at both room temperature and 43 ° C. (110 ° F).

EXAMPLE 3.

Enzyme-containing, builder-containing, liquid detergent agents Η, I and J were formulated substantially similar to agents F and G of Example 2, except that they contained a mixture of protease and α-amylase enzymes instead of a single protease enzyme. The funds are shown in Table 3 below.

TABLE 3.

Η I J

Sodium dodecylbenzenesulfonate 7% 7% 7%

Ethoxylated C --C ^ alcohol sulfate (3 moles EO / mole of alcohol) 777

Optical Bleach 0.2 0.2 0.2

Sodium citrate 12 12 12 PBB {1) 111 ^ 5 Perfume 0.3 0.3 0.3 (2)

Protease enzyme 111 (3) α-amylase enzyme 0.4 0.4 0.4

Propylene Glycol 20 20 20

Borax 1 3 30 ------- remainder --------

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Η I J

S active enzyme after 4 days at 43 ° C approx. (110 ° F): α-amylase enzyme 50% 67% 87% Protease enzyme 30 73 94 (1) "Polar Brilliant Blue" - a 1% active color solution.

(2) "Esperase" sold by Novo Industries containing 5% enzyme, 75% propylene glycol and the residue H 2 O with an activity 10 of 8.0 KNPU / g (kilogram Novo protease units / g).

(3) "Thermamyl" sold by Novo Industries containing 5% enzyme, 18% NaCl and the residue H 2 O with an activity of 120,000 Novo amylase units per g.

The agents I and J according to the invention showed a markedly more stable enzyme activity after 4 days for both the protease and amylase enzymes relative to agent H, which did not contain boron compound and consequently lost approx. 1/2 of the original amylolytic activity and approx. 1/3 of the initial proteolytic activity over the 4-day period.

All three agents were clear, single-phase solutions that remained physically stable after 6 months of storage.

Claims (4)

A stabilized aqueous, aqueous, clear, single-phase, enzyme-containing liquid detergent, characterized in that it comprises (a) from 8 to 20% by weight of one or more surfactant, anionic surfactants, 10 (b) from (C) an effective amount of an enzyme or enzyme mixture selected from alkaline protease enzymes and alpha-amylase enzymes; (d) an enzyme stabilizing system which - calculated on the detergent agent's composition, comprises about 5% to 25% by weight of a water-soluble non-phosphate-containing detergent builder salt; weight - contains (i) from 12 to 25% propylene glycol and (ii) from 1 to 5% of a boron compound selected from 20 boric acid, boron oxide and alkali metal borates, and (e) from 25 to 75% by weight water. Detergent according to claim 1, characterized in that the builder salt is sodium citrate. An herbicide according to claim 1, characterized in that the builder salt is sodium nitrilotriacetate. 4. Detergent composition according to claim 1, characterized in that it contains from ca. 15 to 20% by weight of propylene glycol and from approx. 1 to 3% by weight of the boron compound. 35