CN107592883B - Laundry detergent compositions - Google Patents

Abstract

The present invention provides enzymatic and dispersant formulations for home laundry comprising alkyl ether carboxylic acids, protease enzymes, anionic surfactants and optionally nonionic surfactants.

Description

Laundry detergent compositions

Technical Field

The present invention provides enzymatic and dispersant formulations for use in domestic laundry.

Background

Laundry detergent formulations containing a high fraction (fraction) of anionic surfactant relative to nonionic surfactant are ubiquitous.

Proteases are used in laundry detergent formulations to remove protein-containing stains from fabrics.

WO2013/087286(Unilever) discloses liquid formulations containing alkyl ether carboxylic acids, betaines, anionic surfactants, nonionic surfactants for providing softening benefits.

DE 3320340 discloses laundry detergent formulations containing alkyl ether carboxylates having 4.5 ethoxylate units and a protease. In example a of DE 3320340, it is shown that this formulation does not stabilize proteases during storage. In examples B, D and E of DE 3320340, formulations containing an alkyl ether carboxylate having 3.8 ethoxylate units and a protease are stabilized against some proteases.

There is a need to increase the detergency of laundry formulations containing high fractions of anionic surfactants relative to nonionic surfactants.

Disclosure of Invention

Surprisingly, the combination of protease with specific alkyl ether carboxylic acids provides enhanced stain removal.

In one aspect, the present invention provides a laundry detergent composition comprising:

(i) from 5 to 50 wt%, preferably from 6 to 30 wt%, more preferably from 8 to 20 wt% of a surfactant selected from anionic surfactants and nonionic surfactants;

wherein the weight fraction of non-ionic surfactant/anionic surfactant is from 0 to 0.3, preferably from 0 to 0.15, most preferably from 0.05 to 0.12;

(ii)0.5 to 20 wt%, preferably 1.5 to 10 wt%, most preferably 2.5 to 5 wt% of an alkyl ether carboxylic acid dispersant having the structure:

R-(OCH₂CH₂)_n-OCH₂-COOH，

wherein:

r is selected from the group consisting of saturated and monounsaturated C10 to C26 linear or branched alkyl chains, preferably C12 to C24 linear or branched alkyl chains, most preferably C16 to C20 linear alkyl chains;

n is selected from 5 to 20, preferably 7 to 13, more preferably 8 to 12, most preferably 9.5 to 10.5; and the combination of (a) and (b),

(iii)0.0005 to 0.2 wt.%, preferably 0.002 to 0.02 wt.% protease.

Preferably, the protease is a serine protease, more preferably a subtilase (subtilase) type serine protease, most preferably a subtilisin (subtilisin) subtilisin type serine protease.

The weight% of anionic surfactant was calculated as sodium salt. The wt% of alkyl ether carboxylic acid dispersant is calculated as COOH form. With respect to the above, the alkyl ether carboxylic acid dispersant is not included as an anionic surfactant.

In another aspect, the present invention provides a domestic method of treating a textile, the method comprising the steps of:

(i) treating a textile with an aqueous solution of at least 1g/L of a laundry detergent composition as defined in any preceding claim; and the combination of (a) and (b),

(ii) the aqueous laundry detergent solution is left in contact with the textile for 10 minutes to 2 days, and then the textile is rinsed and dried.

Detailed Description

Detergent forms

Preferably, the laundry detergent formulation is a non-phosphate-assisted laundry detergent formulation, i.e. containing less than 1 wt% phosphate. Preferably, the powder laundry detergent formulation is predominantly carbonate-assisted. The powder should preferably give a pH of 9.5-11 in use.

Most preferably, the laundry detergent is an aqueous liquid laundry detergent, preferably having a pH of 7 to 9.

Protease enzyme

Proteases hydrolyze the peptides and bonds within the protein, which results in enhanced removal of protein or peptide containing stains in a laundry environment. Examples of suitable protease families include aspartic proteases, cysteine proteases, glutamic proteases, asparagine (aspargegine) peptide lyases, serine proteases and threonine proteases. These protease families are described in the MEROPS peptidase database (http:// polymers. sanger. ac. uk /). Serine proteases are preferred. The subtilisin type serine proteases are more preferred. The term "subtilase" refers to the subgroup of serine proteases according to Siezen et al, Protein Engng.4(1991)719-737 and Siezen et al, Protein Science 6(1997) 501-523. Serine proteases are a subset of proteases characterized by a serine at the active site, which forms a covalent adduct with a substrate. Subtilases can be divided into 6 sub-classes, namely the subtilisin family, the thermolysin (thermolase) family, the proteinase K family, the lanthionine (Lantibiotic) peptidase family, the Kexin family and the Pyrolysin family.

Examples of subtilases are those derived from Bacillus such as Bacillus lentus, Bacillus alkalophilus, Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus pumilus and Bacillus gibsonii described in US7262042 and WO09/021867, as well as subtilisin (subtilisin lentius), subtilisin Novo, subtilisin Carlsberg, Bacillus licheniformis, subtilisin BPN', subtilisin 309, subtilisin 147 and subtilisin 168 described in WO89/06279, and the protease PD138 described in WO 93/18140. Other useful proteases may be those described in WO92/175177, WO01/016285, WO02/026024 and WO 02/016547. Examples of trypsin-like proteases are trypsin (e.g.of porcine or bovine origin) and fusarium protease as described in WO89/06270, WO94/25583 and WO05/040372, and chymotrypsin protease derived from Cellulonas (Cellumonas) as described in WO05/052161 and WO 05/052146.

Further examples of useful proteases are the variants described in WO92/19729, WO96/034946, WO98/20115, WO98/20116, WO99/011768, WO01/44452, WO03/006602, WO04/03186, WO04/041979, WO07/006305, WO11/036263, WO11/036264, in particular variants with substitutions in one or more of the following positions using BNP' numbering: 3, 4, 9, 15, 27, 36, 57, 68, 76, 87, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 106, 118, 120, 123, 128, 129, 130, 160, 167, 170, 194, 195, 199, 205, 206, 217, 218, 222, 224, 232, 235, 236, 245, 248, 252, and 274. More preferred subtilase variants may comprise the following mutations: S3T, V4I, S9R, A15T, K27R,^*36D,V68A,N76D,N87S,R,^*97E, a98S, S99G, D, a, S99AD, S101G, M, RS103A, V104I, Y, N, S106A, G118V, R, H120D, N123S, S128L, P129Q, S130A, G160D, Y167A, R170S, a194P, G195E, V199M, V205I, L217D, N218D, M222S, a232V, K235L, Q236H, Q245R, N252K, T274A (using BNP' numbering).

Most preferably, the protease is subtilisin (EC 3.4.21.62).

Examples of subtilases are those derived from Bacillus such as Bacillus lentus, Bacillus alkalophilus, Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus pumilus and Bacillus gibsonii described in US7262042 and WO09/021867, as well as subtilisin tarda, subtilisin Novo, subtilisin Carlsberg, Bacillus licheniformis, subtilisin BPN', subtilisin 309, subtilisin 147 and subtilisin 168 described in WO89/06279, and protease PD138 described in WO 93/18140. Preferably, the subtilisin is derived from Bacillus, preferably Bacillus lentus, Bacillus alkalophilus, Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus pumilus and Bacillus gibsonii, as described in U.S. Pat. No. 6,312,936B1, U.S. Pat. No. 5,679,630, U.S. Pat. No. 4,760,025, U.S. Pat. No. 3, 7,262,042 and WO 09/021867. Most preferably, the subtilisin is derived from Bacillus gibsonii or Bacillus lentus.

Suitable commercially available proteases include those under the trade name

Duralase^TM，Durazym^TM，

Ultra，

Ultra，

Ultra，

Ultra，

And

those sold, all as

Or

(Novozymes A/S).

Tradename from Genencor International

Purafect

Purafect

And Purafect

Those that are sold.

Under the trade name of

Purafect

Preferenz^TM，Purafect

Purafect

Purafect

Effectenz^TM，

And

(Danisco/DuPont)，Axapem^TM(Gist-Brocases n.v.) those sold.

Those available from Henkel/Kemira, i.e., BLAP (sequence shown in FIG. 29 of US 5,352,604 with the following mutations: S99D + S101R + S103A + V104I + G159S; hereinafter referred to as BLAP), BLAP R (BLAP with S3T + V4I + V199M + V205I + L217D), BLAP X (BLAP with S3T + V4I + V205I) and BLAP F49 (BLAP with S3T + V4I + A194P + V199M + V205I + L217D), all from Henkel/Kemira; and KAP (alkalophilic bacillus subtilisin with a230V + S256G + S259N mutation) from Kao.

Alkyl ether carboxylic acids

In the context of the present invention, alkyl ether carboxylic acid dispersants are not included as anionic surfactants. The weight of the alkyl ether carboxylic acid is calculated as the protonated form R- (OCH)₂CH₂)_n-OCH₂COOH. They may be used as salts, for example sodium or amine salts.

The alkyl chain may be straight or branched, preferably it is straight.

The alkyl chain may be aliphatic or contain one cis double bond.

Alkyl chain is most preferably CH₃(CH₂)₇CH＝CH(CH₂)₈-。

The alkyl ether carboxylic acids most preferably have the following structure:

CH₃(CH₂)₇CH＝CH(CH₂)₈(OCH₂CH₂)₁₀OCH₂COOH。

the alkyl ether carboxylic acid can be obtained from Kao

Huntsman

And Clariant

And (4) obtaining.

Surface active agent

The laundry composition comprises an anionically charged surfactant (which includes mixtures of anionically charged surfactants).

Suitable anionic detergent compounds which may be used are typically water-soluble alkali metal salts of organic sulphates and sulphonates having alkyl radicals containing from about 8 to about 22 carbon atoms, the term alkyl being used to include the alkyl portion of higher alkyl radicals.

Examples of suitable synthetic anionic detergent compounds are sodium and potassium alkyl sulphates, especially by reacting higher C's, for example prepared from tallow or coconut oil₈To C₁₈Those obtained by sulfating alcohols, alkyl C₉To C₂₀Sodium and potassium benzene-sulphonates, especially linear secondary alkyl C₁₀To C₁₅Sodium benzenesulfonate; and sodium alkyl glyceryl ether sulfates, particularly those ethers of higher alcohols derived from tallow or coconut oil and synthetic alcohols derived from petroleum.

The anionic surfactant is preferably selected from: linear alkyl benzene sulfonate; an alkyl sulfate; alkyl ether sulfates; soap; alkyl (preferably methyl) ester sulfonates and mixtures thereof.

Most preferred anionic surfactants are selected from: linear alkyl benzene sulfonate; an alkyl sulfate; alkyl ether sulfates and mixtures thereof. Preferably, the alkyl ether sulphate is C with an average of 1 to 3 EO (ethoxylate) units₁₂-C₁₄N-alkyl ether sulfates. Sodium lauryl ether sulphate is particularly preferred (SLES). Preferably, the linear alkylbenzene sulfonate is C₁₁To C₁₅Sodium alkyl benzene sulfonate. Preferably, the alkyl sulfates are linear or branched C₁₂To C₁₈Sodium alkyl sulfate. Sodium dodecyl sulfate is particularly preferred (SDS, also known as primary alkyl sulfate).

The level of anionic surfactant in the laundry composition is preferably (i) from 5 to 50 wt% of negatively charged surfactant, preferably the level of negatively charged surfactant is from 6 to 30 wt%, more preferably from 8 to 20 wt%.

Preferably, two or more anionic surfactants are present, preferably linear alkyl benzene sulphonate together with alkyl ether sulphate.

The nonionic surfactant may be present in a surfactant mixture.

Suitable nonionic detergent compounds which may be used include, in particular, the reaction products of compounds having an aliphatic hydrophobic group and a reactive hydrogen atom, such as fatty alcohols, acids or amides, with ethylene oxide, in particular (alone or together with propylene oxide). Preferred nonionic detergent compounds are aliphatic C₈To C₁₈Condensation products of linear or branched primary or secondary alcohols with ethylene oxide.

Preferably, the alkyl ethoxylated nonionic surfactant is C₈To C₁₈Primary alcohols, having an average ethoxylation of from 7EO to 9EO units.

Builders or complexing agents

The builder material may be selected from 1) calcium sequestrant materials, 2) precipitation materials, 3) calcium ion exchange materials and 4) mixtures thereof.

Examples of calcium sequestrant builder materials include alkali metal polyphosphates, such as sodium tripolyphosphate, and organic sequestrants, such as ethylenediaminetetraacetic acid.

Examples of precipitating builder materials include sodium orthophosphate and sodium carbonate.

Examples of calcium ion exchange builder materials include various types of water-insoluble crystalline or amorphous aluminosilicates, of which zeolites are the most well known representatives, for example zeolite ｃA, zeolite B (also known as zeolite P), zeolite C, zeolite X, zeolite Y and the zeolite P type as described in EP- ｃA-0,384,070.

The composition may also contain 0-65% of a builder or complexing agent, such as ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, alkyl or alkenyl succinic acid, nitrilotriacetic acid or other builders mentioned below. Many builders are likewise bleach stabilizers by virtue of their ability to complex metal ions.

Zeolites and carbonates (including bicarbonates and sesquicarbonates)) are preferred builders for powder detergents.

The composition may contain as builder a crystalline aluminosilicate, preferably an alkali metal aluminosilicate, more preferably a sodium aluminosilicate. This is typically present at a level of less than 15 wt%. Aluminosilicates are materials having the general formula:

0.8-1.5M₂O.Al₂O₃.0.8-6SiO₂

wherein M is a monovalent cation, preferably sodium. These materials contain some bound water and need to have a calcium ion exchange capacity of at least 50 mgCaO/g. Preferred sodium aluminosilicates contain 1.5-3.5 SiO in the above formula₂And (4) units. They can be easily prepared by reaction between sodium silicate and sodium aluminate, as well described in the literature. The ratio of surfactant to aluminosilicate (when present) is preferably greater than 5:2, more preferably greater than 3: 1.

Alternatively, or in addition to aluminosilicate builders, phosphate builders may be used. In the art, the term "phosphate" includes diphosphate, triphosphate and phosphonate species. Other forms of builders include silicates, such as soluble silicates, metasilicates, layered silicates (e.g., SKS-6 from Hoechst).

Preferably, the laundry detergent formulation is a non-phosphate-assisted laundry detergent formulation, i.e. containing less than 1 wt% phosphate. Preferably, the powder laundry detergent formulation is carbonate-assisted.

Fluorescent agent

The composition preferably comprises a fluorescent agent (brightener). Fluorescent agents are well known, and many such fluorescent agents are commercially available. Typically, these fluorescent agents are provided and used in the form of their alkali metal salts, e.g., sodium salts. The total amount of fluorescer or fluorescers used in the composition is typically from 0.005 to 2 wt%, more preferably from 0.01 to 0.1 wt%. Preferred classes of fluorescers are: distyrylbiphenyl compounds, such as Tinopal (trade mark) CBS-X, diaminostilbene disulphonic acid compounds, such as Tinopal DMS pure Xtra and Blankophor (trade mark) HRH, and pyrazoline compounds, such as Blankophor SN. Preferred fluorescent agents are: sodium 2- (4-styryl-3-sulfophenyl) -2H-naphtho (napthol) [1,2-d ] triazole, disodium 4,4' -bis { [ (4-anilino-6- (N-methyl-N-2-hydroxyethyl) amino-1, 3, 5-triazin-2-yl) ] amino } stilbene-2-2 ' -disulfonate, disodium 4,4' -bis { [ (4-anilino-6-morpholinyl-1, 3, 5-triazin-2-yl) ] amino } stilbene-2-2 ' -disulfonate, and disodium 4,4' -bis (2-sulfostyryl) biphenyl.

It is preferred that the aqueous solution used in the method has the fluorescent agent present. When the fluorescent agent is present in the aqueous solution used in the method, it is preferably from 0.0001 to 0.1g/L, preferably from 0.001 to 0.02 g/L.

Perfume

Preferably, the composition comprises a perfume. The perfume is preferably 0.001 to 3 wt%, most preferably 0.1 to 1 wt%. Many suitable examples of fragrances are provided in the CTFA (Cosmetic, Toiletry and Fragrance Association)1992International layers Guide, published by CFTA Publications, and the OPD1993Chemicals layers Directory 80th annular Edition, published by Schnell Publishing Co.

The presence of multiple perfume components in a formulation is common. In the compositions of the present invention, it is envisaged that four or more, preferably five or more, more preferably six or more, or even seven or more different perfume components will be present.

In the perfume mixture, preferably 15 to 25% by weight is top notes. Top notes are defined by Poucher (Journal of the society of Cosmetic Chemists 6(2):80[1955 ]). Preferred top notes are selected from citrus oil, linalool, linalyl acetate, lavender, dihydromyrcenol, rose oxide and cis-3-hexanol.

Perfumes and top notes can be used to cue the whitening benefits of the present invention.

It is preferred that the laundry treatment composition is devoid of peroxygen bleach, such as sodium percarbonate, sodium perborate and peracids.

Polymer and method of making same

The composition may comprise one or more additional polymers. Examples are carboxymethylcellulose, poly (ethylene glycol), poly (vinyl alcohol), polycarboxylates such as polyacrylates, maleic/acrylic acid copolymers and lauryl methacrylate/acrylic acid copolymers.

Polymers present to prevent dye deposition, such as poly (vinylpyrrolidone), poly (vinylpyridine-N-oxide) and poly (vinylimidazole), are preferably not present in the formulation.

Additional enzymes

One or more additional enzymes are preferably present in the laundry composition of the present invention and when carrying out the method of the present invention.

Preferably, the level of each enzyme in the laundry composition of the present invention is from 0.0001 wt% to 0.1 wt% protein.

The additional enzyme is preferably selected from: amylases, lipases, and cellulases.

Any enzyme present in the composition may be stabilised using conventional stabilisers, for example, a polyol such as propylene glycol or glycerol, a sugar or sugar alcohol, lactic acid, boric acid or a boric acid derivative (e.g. an aromatic borate ester) or a phenyl boronic acid derivative such as 4-formylphenyl boronic acid, and the composition may be formulated as described in, for example, WO92/19709 and WO 92/19708.

Shading dye

Shading dye (shading dye) is preferably present in the formulation at a level of 0.002 to 0.2 wt%.

Dyes are described in Color Chemistry Synthesis, Properties and Applications of organic Dyes and Pigments (H Zollinger, Wiley VCH, Z ü rich, 2003) and Industrial dye Chemistry, Properties Applications (K Hunger (ed), Wiley-VCH Weinheim 2003).

Hueing dyes for laundry detergents preferably have an absorption maximum in the visible range (400-700nm) of greater than 5000Lmol^-1cm^-1Preferably greater than 10000Lmol^-1cm^-1The extinction coefficient of (a). The color of the dye is blue or violet.

Preferred shading dye chromophores are azo, azine, anthraquinone and triphenylmethane.

Azo, anthraquinone, phthalocyanine and triphenylmethane dyes preferably carry a net anionic charge or no charge. Azines preferably carry a net anionic or cationic charge.

During the washing or rinsing step of the washing process, a blue or violet shading dye is deposited onto the fabric, providing a visible shade to the fabric. In this regard, the dye imparts a blue or violet colour to the white cloth with a hue angle of 240 to 345, more preferably 250 to 320, most preferably 250 to 280. The white cloth used in this test was a bleached, non-mercerized woven cotton sheet.

Hueing dyes are discussed in WO2005/003274, WO2006/032327(Unilever), WO2006/032397(Unilever), WO2006/045275(Unilever), WO06/027086(Unilever), WO2008/017570(Unilever), WO2008/141880(Unilever), WO2009/132870(Unilever), WO2009/141173(Unilever), WO2010/099997(Unilever), WO2010/102861(Unilever), WO2010/148624(Unilever), WO2008/087497(P & G), WO2011/011799(P & G), WO2012/054820(P & G), WO2013/142495(P & 151g) and WO2013/151970(P & G).

The monoazo dyes preferably contain a heterocyclic ring, and are most preferably thiophene dyes. The monoazo dyes are preferably alkoxylated and are preferably uncharged or anionically charged at pH 7. Alkoxylated thiophene dyes are discussed in WO/2013/142495 and WO/2008/087497. Preferred examples of thiophene dyes are shown below:

the disazo dye is preferably a sulfonated disazo dye. Preferred examples of sulfonated bisazo compounds are direct violet 7, direct violet 9, direct violet 11, direct violet 26, direct violet 31, direct violet 35, direct violet 40, direct violet 41, direct violet 51, direct violet 66, direct violet 99 and alkoxylated forms thereof. Alkoxylated disazo dyes are discussed in WO2012/054058 and WO 2010/151906.

Examples of alkoxylated disazo dyes are:

the azine dye is preferably selected from sulphonated phenazine dyes and cationic phenazine dyes. Preferred examples are acid blue 98, acid violet 50, dyes having CAS number 72749-80-5, acid blue 59, and phenazine dyes selected from the group consisting of:

wherein:

X₃selected from: -H, -F, -CH₃，-C₂H₅，-OCH₃and-OC₂H₅；

X₄Selected from: -H, -CH₃，-C₂H₅，-OCH₃and-OC₂H₅；

Y₂Selected from: -OH, -OCH₂CH₂OH，-CH(OH)CH₂OH，-OC(O)CH₃And C (O) OCH₃。

The hueing dye is present in the composition at 0.0001 to 0.5 wt%, preferably 0.001 to 0.1 wt%. Depending on the nature of the hueing dye, there is a preferred range depending on the potency of the hueing dye, which depends on the class and the specific potency within any particular class. As mentioned above, the hueing dye is a blue or violet hueing dye.

Mixtures of hueing dyes may be used.

Most preferably, the hueing dye is a reactive blue anthraquinone dye covalently linked to an alkoxylated polyethyleneimine. The alkoxylation is preferably selected from ethoxylation and propoxylation, most preferably propoxylation. Preferably, 80 to 95 mole% of the N-H groups in the polyethyleneimine are replaced by isopropanol groups by propoxylation. Preferably, the molecular weight of the polyethyleneimine is 600 to 1800 prior to reaction with the dye and propoxylation.

An example structure of a preferred reactive anthraquinone covalently linked to a propoxylated polyethyleneimine is:

preferred reactive anthraquinone dyes are: reactive blue 1, reactive blue 2, reactive blue 4, reactive blue 5, reactive blue 6, reactive blue 12, reactive blue 16, reactive blue 19, reactive blue 24, reactive blue 27, reactive blue 29, reactive blue 36, reactive blue 44, reactive blue 46, reactive blue 47, reactive blue 49, reactive blue 50, reactive blue 53, reactive blue 55, reactive blue 61, reactive blue 66, reactive blue 68, reactive blue 69, reactive blue 74, reactive blue 86, reactive blue 93, reactive blue 94, reactive blue 101, reactive blue 103, reactive blue 114, reactive blue 117, reactive blue 125, reactive blue 141, reactive blue 142, reactive blue 145, reactive blue 149, reactive blue 155, reactive blue 164, reactive blue 166, reactive blue 177, reactive blue 181, reactive blue 185, reactive blue 188, reactive blue 189, reactive blue 206, reactive blue 208, reactive blue 247, reactive blue 258, reactive blue 261, reactive blue 262, reactive blue 263 and reactive blue 172.

The dyes are listed according to the colour index (Society of Dyers and Colourists/American Association of Textile Chemists and Colourists) classification.

Examples

Example 1

An aqueous liquid laundry detergent was prepared having the following formulation:

composition (I)	By weight%
		Monopropylene glycol	2
Triethylamine	1.5
		C12-C15 alcohol ethoxylates with 7 moles of ethylene oxide	2.1
Straight chain alkyl benzene sulfonate	8.4
		Sodium laureth sulfate with 3 moles of ethylene oxide	10.5
Citric acid	0.5
		Perfume	0.3
Sodium hydroxide	To pH 8.4
		Water (W)	Balance of

This formulation was used to wash 8 EMPA117 stain monitors (blood/milk/ink stains on polyester cotton) of 5 x 5cm in a tester (tergitometer) set at 200 rpm. The wash was carried out with 2.3g/L of the formulation at 35 ℃ in 800ml of 26 ° french hard water for 20 minutes. To simulate oily soils, 12.5g of SBL2004 soil bar (from WarwickEquest) was added to the wash liquor.

Once the wash had been completed, the cotton surveillants were rinsed once in 400ml of clear water, taken out of the dry, and the color was measured on a reflectometer and expressed as CIE L a b values.

An equivalent formulation was tested but with the addition of 8.7 wt% alkyl ether carboxylic acid, where the alkyl group was cis-9-octadecene. The average number of ethoxy groups varies from 2 to 10.

(iv) addition and non-addition of subtilisin serine protease (EC No. 232-

16L from Novozymes), repeat the experiment. The enzyme was added to give 0.009 wt% pure active protein to the formulation.

Also calculated from the standard deviation of the measurements of the 8 monitors, a 95% confidence limit is given.

Inclusion of protease and alkyl ether carboxylic acid into the formulation increased stain removal as seen by the higher value of L. The increase is greater for 5EO, 8EO and greatest for 10 EO. The combination of protease and alkyl ether carboxylic acids with 5EO, 8EO and 10EO gave a greater increase in stain removal than would be expected from the combination of single component effects. For 5 EO/protease, an expected value of L × 56.08, to yield 58.04. For 8 EO/protease, the expected value is 55.76, giving 58.54. This increase was maximal for 10 EO/protease with an expected value of 57.28, to obtain 60.90.

Claims (15)

1. A non-phosphate-assisted laundry detergent composition comprising:

(i)5 to 50 wt% of a surfactant selected from the group consisting of anionic surfactants and nonionic surfactants;

wherein the weight fraction of nonionic surfactant/anionic surfactant is from 0 to 0.3;

(ii)0.5 to 20 weight percent of an alkyl ether carboxylic acid dispersant having the structure:

R-(OCH₂CH₂)_n-OCH₂-COOH，

wherein:

r is selected from saturated and monounsaturated C10 to C26 straight or branched alkyl chains, and wherein n is selected from 5 to 20; and the combination of (a) and (b),

(iii)0.0005 to 0.2 wt% protease.

2. The non-phosphate-assisted laundry detergent composition according to claim 1, wherein the anionic surfactant is selected from the group consisting of: linear alkyl benzene sulfonate; an alkyl sulfate; alkyl ether sulfates; and mixtures thereof, and the nonionic surfactant is selected from the group consisting of: alkyl ethers having 7 to 9 ethoxy groups.

3. A non-phosphate-assisted laundry detergent composition according to claim 1 or 2, wherein the protease is a serine protease.

4. A non-phosphate-assisted laundry detergent composition according to claim 3, wherein the protease is a subtilisin-type serine protease and two or more anionic surfactants are present and two of the anionic surfactants are linear alkylbenzene sulphonate together with an alkyl ether sulphate.

5. A non-phosphate-built laundry detergent composition according to claim 1 or 2, wherein n is selected from 7 to 13.

6. A non-phosphate-built laundry detergent composition according to claim 1 or 2, wherein the composition is an aqueous laundry liquid detergent.

7. A non-phosphate-built laundry detergent composition according to claim 1 or 2, wherein n is selected from 9.5 to 10.5.

8. The non-phosphate-built laundry detergent composition according to claim 1 or 2, wherein R is selected from monounsaturated C10 to C26 straight or branched alkyl chains.

9. A non-phosphate-built laundry detergent composition according to claim 1 or 2, wherein the alkyl ether carboxylic acid dispersant is:

CH₃(CH₂)₇CH＝CH(CH₂)₈(OCH₂CH₂)₁₀OCH₂COOH。

10. a non-phosphate-built laundry detergent composition according to claim 1 or 2, wherein the anionic surfactant and nonionic surfactant are present in the range of from 8 to 20 wt%.

11. A non-phosphate-built laundry detergent composition according to claim 1 or 2, wherein the weight fraction of nonionic surfactant/anionic surfactant is from 0.05 to 0.12.

12. A non-phosphate built laundry detergent composition according to claim 1 or 2, wherein the alkyl ether carboxylic acid dispersant is present in the range of 1.5 to 10 wt%.

13. The non-phosphate-assisted laundry detergent composition according to claim 1 or 2, wherein the laundry detergent is an aqueous liquid laundry detergent having a pH of from 7 to 9.

14. The non-phosphate-built laundry detergent composition according to claim 1 or 2, wherein the laundry detergent composition is a carbonate-built powder laundry detergent formulation.

15. A domestic method of treating a textile, the method comprising the steps of:

(i) treating a textile with an aqueous solution of at least 1g/L of a non-phosphate-assisted laundry detergent composition as defined in any preceding claim; and the combination of (a) and (b),

(ii) the aqueous laundry detergent solution is left in contact with the textile for 10 minutes to 2 days, and then the textile is rinsed and dried.