PT78653B

PT78653B - Process for preparing built single-phase liquid anionic detergent composition containing stabilized enzymes

Info

Publication number: PT78653B
Application number: PT78653A
Authority: PT
Inventors: Jack Thomas Inamorato; Michael Christopher Crossin
Original assignee: Colgate Palmolive Co
Priority date: 1983-05-31
Filing date: 1984-05-28
Publication date: 1986-06-18
Also published as: DE3418294A1; IT8448275A0; AU558722B2; DK159881C; IE58061B1; SG44890G; CH660374A5; ZA843665B; ATA178384A; HK67490A; PT78653A; GB2140819B; MX162796A; AT394385B; BR8402593A; BE899778A; MY102605A; NO160451C; CA1220741A; NO842163L

Abstract

A stabilized built single-phase enzyme-containing liquid detergent composition is provided comprising: (a) 8 to 20%, by weight, of a surface active anionic detergent compound; (b) 5 to 25% of a water-soluble non-phosphate detergent builder salt; (c) an effective amount of an enzyme or enzyme mixture selected from alkaline protease enzymes and alpha-amylase enzymes; (d) an enzyme stabilizing system containing, based on the weight of the detergent composition, (i) 12 to 25% of propylene glycol and (ii) 1 to 5% of a boron compound which is boric acid, boric oxide or an alkali metal borate, or a mixture thereof; and (e) 25 to 75% by weight of water. z

Description

DETAILED DESCRIPTION OF THE INVENTION

The enzyme stabilizing system object of this invention is a mixture of propylene glycol and a boron compound selected from the group consisting of boric acid, boric oxide and alkali metal borate capable of reacting with propylene glycol. The amount of propylene glycol is from about 12 to 25%, preferably from about 15 to 20% by weight, and the amount of the boron compound may range from about 1 to 5%, preferably from about 1% to 5% by weight of the composition. Suitable alkaline enzymes suitable for the present compositions include the various commercial liquid preparations with enzymes, which have been adapted for use in detergent compositions, as well as useful powdered enzyme preparations, although, as a general rule, they are less suitable for use in detergent compositions. incorporation into structured liquid detergent compositions. Thus suitable liquid preparations with enzymes include Alcalase and Esperase sold by Novo Industries, Copenhagen, Denmark and Maxatase and AZ-Protease sold by Gist-Brocades, Delft, The Netherlands. preferred for the present composition due to the present composition due to its optimized activity with high pH values corresponding to the structured detergent compositions.

Suitable liquid enzyme preparations-amylases include those sold by Novo Industries and Gist-Brocades under the trade names "Fermamyl" and "Maxamyl", respectively.

The synthetic anionic detergent used in the process of the invention may be any of

of a wide variety of those compounds which are well known and described throughout the text "Surface Actin Agents" Vol. II, by Schwartz, Peny and Berch, published in 1958 by Interscience Publishers, the disclosures relating thereto detergent compositions incorporated herein by reference.

The detergent compounds

(10 to 18 or 20 carbon atoms) -benzenesulfonate salts, characterized in that the alkyl group preferably comprises from 10 to 15 carbon atoms, more preferably an alkyl radical of the unmodified chain of 12 or 13 carbon atoms. Preferably, such an alkyl benzene sulfonate has a high content of 3 (or higher) -phenyl isomers and a correspondingly low (usually less than 50%) value of 2- (or lower) -phenyl isomers in other words , the benzo ring is preferably attached in large part to the position

3,4,5,6 or 7 of the alkyl group and the content of isomers to which the benzene ring is attached in the 1 or 2 position is correspondingly low. Typical alkyl benzene and sulfonate surfactants are described in U.S. Patent 3,320,174. Of course, the more branched alkyl benzene sulfonates may also be used, but are generally not preferred because of their lack of biodegradability.

Other anionic detergents

which are useful, are the olefin sulphonate salts. These generally include long chain alkenyl sulfonates or long chain hydroxy-alkane sulfonates (the OH being on the carbon atom, which is not directly attached to the carbon atom containing the -SO 2 H group). The detergent

olefin sulfonate generally consists of a mixture of these types of compounds, in amounts which vary, often

together with long chain disulfonates or sulphate sulfonates. These olefin sulfonates are disclosed in patents such as in U.S. Pat. 2,061,618; 3,409,637; 3,332,880; 3,420,875; 3-428,654;

3-506,580; and in U.S. Pat. 1,129,158. The number of carbon atoms in the olefin sulphonate is generally in the range of 10 to 25, more usually 10 to 18 or 20, for example a mixture of C,,, 14 ^e e ^and 16 * apos, by retiring a mean of about of 14 carbon atoms or a mixture principally of C, e e and Oq »apresent having an average of about 16 carbon atoms. Another class of useful anionic detergents is that of the higher paraffin sulfonates. These may be primary paraffin sulfonates resulting from the reaction of long chain alpha olefins and bisulfites, for example sodium bisulfite, or paraffin sulfonates, the sulfonate groups distributed along the paraffin chain, such as the products resulting from reaction of a long-chain paraffin with sulfur dioxide and oxy genus under ultraviolet light, followed by neutralization with sodium hydroxide or other suitable base (such as in U.S. Patents 2,503,280, 2,507,088, 3,260,741 ;

3,372,188; and in German Patent 735,096). The paraffin sulfonates preferably include from 13 to 17 carbon atoms and will normally be the monosulfonates, but are preferred. may be di- or tri-sulfonates. Typically the di- and polysulfonates will be used in admixture with a corresponding monosulfonate, for example in the form of a mixture of mono- and disulfonates containing up to about 3θ% of the disulfonate. The hydrocarbon substituent is preferably linear, but if desired, branched-chain paraffin sulfonates may be used, although these are inferior with respect to biodegradability.

Other suitable anionic detergents are sulphated ethoxylated higher fatty alcohols of the formula R0 (C2 H4 O) _m SO4 M, where R is a fatty alkyl of 10 to 18 or 20 carbon atoms, m is 2 to 6 or 8 (preferably having a value of about 5 ^to 1/2 of the number of carbon atoms in R) and M is a cation for solubilizing salt formation, such as an alkali metal, ammonium, lower alkylamino or lower alkanolamine, or a higher alkyl benzene sulfonate characterized in that the higher alkyl is 10 to 15 carbon atoms. Ethylene oxide is the preferred lower alkylene oxide of the anionic alkoxylated detergent, and its proportion in the polyethoxylated higher alkanol sulphate is preferably 2 to 5 mol of ethylene oxide groups present per mole of anionic detergent, more preferred with three moles, especially when the higher alkanol is 11 or 12 to 15 carbon atoms. In order to maintain the desired hydrophilic-lipophilic balance, when the content of alkyl carbon atoms is in the lower part of the range of 10 to 18 carbon atoms, the ethylene oxide content of the detergent can be reduced to about two mol by mole, whereas when the higher alkanol is from 16 to 18 carbon atoms in the upper range, the number of ethylene oxide groups may be increased to 4 or 5% in some cases to values as high as 8 or 9. Similarly, the cation for salt formation can be altered to obtain the best solubility. It may be any suitably solubilizing metal or radical, but will more often be an alkali metal, for example sodium or ammonium. If lower alkylamine or alkanolamine groups are used, the alkyls and alkanols will usually consist of 1 to 4 carbon atoms and the amines and alkanolamines may be mono-, di- and tri-substituted, such as in monoethanolamine, diisopropanolamine and trimethylamine. The poly-lower alkoxy alkanol sulfates may be used in combination with other preferred anionic detergents,

such as the alkyl superior benzenesulfonates, in order to provide optimum detergency in the present structured liquid detergent compositions. A preferred polyethoxylated alcohol sulfate detergent is sold by the Shell Chemical Company, and is marketed with. signação of Neochol 25-3 ^S · Examples of the polyethenoxy higher alcohol sulfates which may be used in the liquid detergent compositions of the invention include: alkyl C ^ 2 ^m I ^S ^ normal or primary ° - trietenoxi - sulfate, sodium salt: myristyl -trietenoxysulfate, potassium salt; n-decyl-diethenoxy sulfate, diethanolamine salt, lauryl diethenoxy sulfate, ammonium salt; palmitil-tetra-ethenoxy sulfate, sodium salt; mixed alkyl nor

primary tri- and tetra-etenoxy-mixed sulfate, sodium stearyl-pentaethoxysulfate salt, trimethylamine salt; and normal primary alkyl trietenoxysulfate, potassium salt.

Other useful anionic detergents include acyl superior sarcosinates, for example sodium N-lauryl sarcosinate; sulfates of higher fatty alcohol, such as sodium lauryl sulfate, sodium sulfate, alcohol sulfate; sulfates of mono or glycerides of higher fatty acids, for example, stearic minoglyceride monosulfate; although of these, sodium sulphates of higher alcohol have been found to be lower in detergency than polyethoxylated sulphates; aromatic-lower alkylene) ether sulfates such as the sulfates of the condensation products of ethylene oxide and nonylphenol (usually containing 1 to 20 oxyethylene groups per moleule, preferably 2 to 12): fatty alcohol polyethoxy sulfates and polyethoxy sulfates of alkyl phenol containing a lower alkoxy substituent (of 1 to 4 carbon atoms, for example methoxy) on a carbon near that containing the group of sulfates, such as the monomethyl ether sulfate of a long chain vicinal glycol, mixture of vicinal alkanols of 16 to 20 carbon atoms in an unmodified chain; acyl ester of isethionic acid, for example oleyl acyl-N-methyl taureth isethionates for example N-methyl lauroyl or potassium oleyl taurethes; higher alkyl phenyl polyethoxy sulfonates; higher alkyl phenyl disulfonates, for example pentadecyl phenyl disulfonate; and higher fatty acid soaps, for example coconut oil and tallow mixed soaps in a 1: 4 ratio.

Among the types previously

mentioned hereinabove of anionic detergents, sulfates and sulfonates are generally preferred, although the corresponding organic phosphates and phosphonates may also be used when their phosphorus content is not subject to objections. Generally, water-soluble anionic synthetic organic detergents (including soap) are salts of alkali metal cations, such as potassium, lithium and especially sodium, although salts of ammonium, substituted ammonium cations such as those previously described, for example, triethanolamine, triisopropylamine.

Optionally, a nonionic detergent in minor amounts may be used to complete the anionic detergent compound in the present structured liquid detergent compositions. When used in such an association with an anionic detergent, the amount of nonionic detergent will generally represent less than about 10%, and preferably less than about 5%, by weight, of the total composition.

Nonionic detergents

are usually poly-lower alkoxy lipophils, characterized in that the desired hydrophilic-hypophilic balance is obtained by addition of a lower polyalkoxy hydrophilic group to a lipophilic fraction. In the present compositions the nonionic detergent used is preferably a poly (lower) alkoxylated lower alkanol characterized in that the alkanol includes from 10 to 18 carbon atoms and wherein the number of moles of the lower alkylene oxide ( of 2 or 3 carbon atoms) is from 3 to 12. Of these materials, it is preferred to use those characterized in that the higher alkanol is a higher fatty alcohol. of 11 or 15 carbon atoms, consisting of 5 ^to 8 or 5 to 9 lower alkoxy groups per mole. Preferably, the lower alkoxy is ethoxy, but in some cases, may be desirably mixed with propoxy, the latter being usually present, a minor (less than 50%) pool. Examples of such compounds are those characterized in that the alkanol is from 12 to 15 carbon atoms and consists of about 7 ethylene oxide groups per mole, for example Neodol 25-7 and Neodol 23-6.5 , which products are manufactured by Shell Chemical Company, Inc. The first is a condensation product of a mixture of higher fatty alcohols having on average about 12 to 15 carbon atoms with about 7 moles of ethylene oxide, and the second is a corresponding mixture characterized in that the carbon content of the higher fatty alcohol is 12 to 13 and the number of ethylene oxide groups per mole is on the average of 6.5. Higher alcohols are primary alkaloids. Other examples of such detergents include tergitol 15-S-7 and Tergitol 15-S-9, which are both linear secondary alcohol ethoxylates, manufactured by Union Carbide Corporation.

The first is a mixed ethoxylation product of a linear secondary alkanol of 11 to 15 carbon atoms with 7 moles of ethylene oxide, and the second is a similar product but with 9 mol of ethylene oxide, which is reacted. Also useful in the present compositions are the higher molecular weight nonionics such as Neodol 45-11 which are similar condensation products of ethylene oxide of alcohols

fatty acids with the higher fatty alcohol being 14 to 15 carbon atoms and the number of ethylene oxide groups per mole being about 11. Such products are also manufactured by Shell Chemical Company. Other useful nonionics are shown under the designation of Plusafac B-26 (BASF Chemical Company), a reaction product of a higher linear alcohol and a mixture of ethylene and propylene oxides. In the case of preferred poly-lower alkoxylated alkanols the best balance of hydrophilic and lipophilic fractions is obtained when the number of lower alkoxys is from about 40% to 100% of the number of carbon atoms in the higher alcohol, preferably 40 to 60 % of that number. The nonionic detergent preferably consists of at least 5% of the preferred ethoxylated alkanols. The higher molecular weight alkanols and various other normally solid nonionic detergent compounds and surface active agents can contribute to the liquid detergent composition becoming gel and therefore are normally omitted or limited in quantity in the present compositions, although minor proportions can be used because of their cleaning properties, etc. With respect to both the preferred and the least preferred nonionic detergents, the alkyl groups present therein are preferably linear, although a minor degree of slight branching, such as a carbon or two carbons near the terminal carbon of the unmodified chain and away from the ethoxy chain, with

the proviso that such branched alkyl does not contain more than three carbons in length.

Normally the proportion of

carbon atoms in such a branched configuration will be less, rarely exceeding 20% of the total alkyl carbon content. Similarly, although linear alkyls, which terminate the ethylene oxide chains, are highly preferred and are considered to be capable of yielding an optimal combination of detergency characteristics, biodepa. and non-gel formation, there may occur in the case of medium or secondary bonds to ethylene oxide. In this case, this usually happens only in a minor proportion of those alkyls, generally less than 20%, but in the case of the above-mentioned "Tergitols" the proportion may be higher. Likewise, when the propylene oxide is present in the oxide chain lower alkylene, it will usually represent less than 20% thereof, and preferably less than 10%. The non-phosphate builder salts for detergents are used in the present compositions in amounts generally in the range of about 5 ^to 25%, and Preferred examples of inorganic, phosphorous and water-soluble inorganic builders include water-soluble inorganic silicate, bicarbonate and carbonate salts. Alkali metal carbonates, bicarbonates and silicates, for example, sodium and potassium, are particularly useful in this process.

The water-soluble organic builders are also useful and include the alkali metal, alkali metal, ammonium and substituted ammonium polyhydroxysulfonates, polycarboxylates, carboxylates and polyacetates. Specific examples of polyacetate

polycarboxylate include sodium, potassium, lithium, ammonium and substituted ammonium salts of ethylenediaminetetraacetic acid, nitrilotriacetic acid, benzenopolycarboxylic acids (i.e. penta- and tetra-), carboxymethysuccinic acid and cetric acid. The percentage of water, the major solvent in the present compositions, will usually be from about 25 to 75%, preferably 40 to 60%, by weight of the liquid composition.

Fluorescent optical fans. or bleaches used in the liquid detergent compositions are important components of the modern detergent compositions which give the laundry and washed materials a shiny appearance so that the laundry is not only clean but also appears clean. While it is possible to use a single brightener for the specific purpose intended in the present liquid detergent compositions, it is generally desirable to use mixtures of brighteners, which will have good brightening effects on cotton, nylon, polyester and blends of these materials, which are also stable in their action of bleaching.

A description of these types of optical brighteners is given in the article "The Fiequirements of Present Day Detergent Pluorescent Vhitenig Agents", by AE Diegrist, J. Am., Oil Chemists Soc. January 1978 (Vol. 55). This article and U.S. Patent 3,812,041, issued May 21, 1974, both incorporated herein by reference, include detailed descriptions of a wide variety of suitable optical brighteners.

Among the enhancers useful in the present liquid detergent compositions are: Oalcofluor 5BM (American Cyanamid); Calcofluor Vhite ALP (American Cyanamid); SOP A-2001 (Ciba); CDV (Hilton-Davis); Phorwite BKH, Phorwite BBH and Phorwite BHA (Verona); CSL, acid powder (American

Oyanamid); PB 766 (Verona); Blancophor PD (GAP); UNPA (Geigy); Tinopal BBS 200 (Geigy).

Adjuvants may be present in the liquid detergent compositions in order to provide additional functional and aesthetic properties. Included among the useful adjuvants are soil suspending agents and anti-foaming agents. such as polyvinyl alcohol, sodium carboxymethyl cellulose, hydroxypropylmethyl cellulose, thickeners, for example, gums, alginates, agar agar, foaming agents, for example, laurao-myristic diethanolamide, foam destroyers, for example, silicas ; bactericides, for example, tribromosalicylanilide, hexachlorophene; dyes; preservative pigments (dispersible in water); ultraviolet absorbers; fabric softeners; opacifying agents, for example "polystyrene suspensions; and perfumes.

These materials will of course be selected based on the pourable properties of the finished product, their compatibility with the other components and their solubility in the liquid composition.

The liquid compositions herein are effective and easy to use. In comparison with reinforced laundry detergent powders, much lower volumes of the present liquors are employed to provide a comparable degree of laundry cleanliness. For example, when using a typical preferred formulation of this invention, only about 132 grams or a glass of liquid are required for a complete washing container of a top loading automatic washing machine in which the volume of water required is 15 to 18 gallons (55 to 75 liters); is

even lower quantity is required for front loading machines. Thus, the concentration of the liquid detergent composition in the wash water is in the range of about 0.2%. Typically, the proportion of the liquid composition in the lavage solution will be in the range of about 0.05 to 0.3%, preferably 0.15 ^to 0.25%. The proportions of the various components of the liquid composition may vary accordingly. Equivalent results may be obtained by using larger portions of a more dilute formulation, but the larger amount required will require additional packaging, which will generally be less convenient for consumer use.

EXAMPLE 1

The structured liquid detergent compositions containing enzymes, AE, were formulated as indicated below, in Table 1.

The percentages given represent percentages by weight.

-18-

Table 1 THE B W D AND Dodecylbenzene sulfo- sodium 7% 7% 7% 7% 7%

Sulfate of ethoxy-

side σ. _or -0. _κ (3 mol 12 1 æ RI / mol of alcohol) 7 7 7 7 7 Reviver 0.2 0 , 2 0.2 0.2 0.2 Sodium nitriotriacetate 15 15 15 15 15 1 1 1 1 1 perfume 0,3 0 , 3 0.3 0.3 0.3 (-5) Protease enzyme 1 1 ¹ 1 1 Propylene glycol --- 20 20 20 20 Borax - - 1 2 jj h ₂ o - TSQTvha Ύ »Α β + * βΤ) 4 * A. ••••••••••••••••••••••••••••••

Percentage of active enzyme after

(a) 4 days at 110 ° F (43 ° C) --- --- --- --- 98%

(b) 6 days at 110 ° P (43 ° C) 0 15 61 86 88

(1) Neodol 25-38 sold by Shell Oil Company.

(2) "Polar Brilliant Blue" a dye solution active 1%

(3) "Wait", sold by Novo Industries, consisting of 5% enzyme, 75% propylene glycol, and the remainder in HgO, having an activity of 8.0 KNPU / g. (units Pico Novo / kg).

The activities of enzymes

of the AE compositions were tested after 6 days of storage at 110Â ° C (43Â ° C), the percentage activity over the initial value * and indicated in Table 1. The activity after 4 days was measured only for the composition E · The compositions A and B were the only compositions which did not contain an enzyme stabilizing system according to the invention and which showed a total loss (composition A) or almost total (composition B) of enzyme activity after 6 days. Compositions 0, D and E reflect the marked improvement in enzyme stability caused by the inclusion of propylene glycol and borax in the detergent composition

Compositions E and E were all homogeneous, single-phase and clean solutions, which maintained their physical stability and clarity after 6 months of storage, both at room temperature and at 110Â ° C (43Â ° C). Composition A which was not in accordance with the invention was physically unstable due to the absence of propylene glycol which, in addition to serving as an enzyme stabilizer (together with

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the above-mentioned boron conposide), promotes the solubility of the anionic detergents and the NTA structuring agent in the aqueous composition.

EXAMPLE 2

Detergent compositions

structured liquids containing enzymes, E and G were formulated essentially similarly to AE compositions, except that sodium citrate was used as the structuring salt instead of sodium NTA. The compositions. tions are shown in Table 2 below.

Table 2

AND

Sodium dodecylbenzenesulfonate 7%

Ethoxylated alcohol sulfate

^C 12 "15 15 ^Μθ1 EO / mole ^of

alcohol) 7

Yield 0.2

Sodium citrate 12

PBB ¹ ) 1

G

7%

7

0.2

12

1

perfume

Protease enzyme ^) Propylene glycol

Borax

^H 20

0.3 0.3

1 1

20 20

2

----- remaining part

Percentage of enzyme

active after 4 days at 110 ° 3? (43øC)

20

95

(1) Polar Brilliant Blue - an active dye solution at 1%

(2) "expected", sold by Novo Industries, consisting of 5% d-β enzyme, 75% propylene glycol, and the remainder in HgO, having an activity of 8.0 KNPU / g.

The composition G according to the invention had an enzyme activity of 95% after four days compared to the composition P which did not contain the boron compound and consequently lost more than 3/4 of its activity enzymes ·

Both compositions were

clear monophasic solutions that remained physically stable after six months of storage at either room temperature or 110 ° F (43 ° C).

ETOPIO 3

Detergent compositions

structured liquids containing enzymes, Η, 1, J, were formulated essentially similar to compositions I and G of Example 2, except those with positions including a mixture of protease and high-amylase enzymes instead of a single protease enzyme . The compositions are shown below in Table 3.

Table 3

Sodium Dodecylbenzenesulfonate

7%

Ethoxylated alcohol sulphate ^σ 2 2 3 4 5 5 5 5 mol / mol alcohol)

Aviv

0.2 0.2 0.2

Sodium citrate PBB-

12

perfume

0.3 0.3 0.3

Protease Enzyme

(2)

Enzyme-amylase

(3)

0.4 0.4 0.4

Propylene glycol

20

Borax

fi ₂ 0

-part remaining

Percentage of active enzyme after 4 days at 110 ° P

enzyme-amylase 50%

protease enzyme 30

67% 87%

73 94

(1) Polar Brilliant Blue - a 1% active dye solution.

(2) "Waiting", sold by Novo Industries, consisting of 5% enzyme, 75% propylene glycol, and the remainder in H 2 O, having an activity of 8.0 KNPU / g / gr)

(3) "Termamyl", sold by Novo Industries, consisting of 5% enzyme, 18% Nacl and part remaining in HgO, having an activity of 120,000 units New amylase per gram

Compositions I and J of

According to the invention, they demonstrate a markedly more stable enzyme activity after four days of both the protease enzyme and the amylase compared to the H composition which did not contain boron compound, which consequently gave about V2 of its initial amylolytic activity and about of V3 from its initial proteolytic activity during the four day period.

The three compositions were

all clear single-phase solutions, which remained physically stable after six months of storage.

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Claims

over there. A process for the preparation of a stabilized, structured, clear, monophasic aqueous liquid detergent composition containing enzymes, characterized in that the composition comprises:

(a) from about 8 to 20% by weight of one or more anionic surfactant detergents,

(b) from about 5 to 25% by weight of a non-phosphated, water-soluble detergent builder salt

(c) an effective amount of an enzyme or mixture of enzymes selected from the group consisting of alkaline protease enzymes and alpha-amylases enzymes;

(d) an enzyme stabilizing system which, based on the weight of the detergent composition, consists of: (i) about 12 to 25% propylene glycol and (ii) from about 1 to 5% of a boron compound selected from the group consisting of boric acid, boric oxide and alkali metal borates; and

(e) from about 25 to 75% by weight of water.

2 ^a . 5. A process according to claim 1, wherein said structuring salt is sodium citrate.

3 ^a . A process according to claim 1, wherein said structuring salt is sodium nitrilotriacetate.

4 ^a . 2. A composition according to claim 1, wherein said composition

the detergent is substantially free of a phosphate-based detergent builder salt.

5 ^a . A process according to claim 1, wherein said detergent composition comprises from about 15 to 20% by weight of a propylene glycol and from about 1 to 3% by weight of said boron compound.

6fi. - Process according to

Claim 1, wherein said boron compound is borax.

· Process according ^to claim 7,

Claim 1, characterized in that said builder salt is present in the composition in an amount of about 10 to 20% by weight.

8 ^a . - Process according to claim 1, wherein the anionic detergent is a mixture of an alkyl salt po ^L ^"c pg born sulío benzene and a polyethoxylated alcohol sulphate salt.

9 ^a . - Method of washes

characterized in that the stained and / or dirty fabrics to be washed are brought into contact with a clear, monophasic, clear liquid detergent composition having enzymes, consisting of:

(a) from about 8 to 20% by weight of one or more anionic surfactant detergent compounds

(b) from about 5 to 25% by weight of a non-phosphated, water-soluble detergent builder salt;

(d) an enzyme stabilizing system, based on the weight of the detergent composition, consisting of: (i) from about 12 to 25% of a propylene glycol and (ii) from about 1 to 5% of a boron compound selected from leave

of the group consisting of boric acid, boric oxide and alkali metal borates; and

(e) from about 25 to 75% ^by weight of water.

10S. Method according to

Claim 9, characterized in that said structuring salt is sodium citrate.

llã. 4. A method according to claim 9, wherein said builder salt is sodium nitrilotriacetate.

12ê. 5. A method according to claim 9 wherein said detergent composition is substantially free of a phosphate builder salt for detergents.

13 ^a . Method according to

Claim 9, characterized in that said detergent composition comprises from about 15 to 20% by weight of propylene glycol and from about 1 to 3% by weight of borax.

-2714®. 8. A method according to claim 9, wherein said detergent composition comprises from about 10 to 20% of a non-phosphated structured salt.

15®. 4. A method according to claim 9 wherein said detergent composition comprises a mixture of a benzene sulfonate alkyl salt and an alcohol sulphate salt θχο θ 18 polyethoxylate