EP3555255B1

EP3555255B1 - Laundry detergent composition

Info

Publication number: EP3555255B1
Application number: EP17793644.0A
Authority: EP
Inventors: Stephen Norman Batchelor
Original assignee: Unilever PLC; Unilever NV
Current assignee: Unilever PLC; Unilever NV
Priority date: 2016-12-15
Filing date: 2017-11-02
Publication date: 2020-06-24
Anticipated expiration: 2037-11-02
Also published as: WO2018108382A1; BR112019011999B1; CN110023469A; ZA201902425B; AR110513A1; EP3555255A1; BR112019011999A2

Description

FIELD OF INVENTION

The present invention provides an effective surfactant formulation for use in domestic laundry.

BACKGROUND OF THE INVENTION

Aqueous domestic laundry liquid formulations containing lauryl ether sulfate in combination with another type of anionic surfactant as the main surfactants are ubiquitous. The second anionic surfactant is typically linear alkyl benzene sulfonate. It is desirous that the surfactants fully dissolve in the water, to provide an aqueous solution of optical clarity; to facilitate this clarity hydrotropes are added. Effective binary anionic surfactant systems that fully dissolve in water without the need for an additional hydrotropes are required. Examples of hydrotropes include ethylene glycol, 1,3 propanediol, 1,2 propanediol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, 2,3-butane diol, 1,3 butanediol, diethylene glycol, triethylene glycol, polyethylene glycol, glycerol formal dipropylene glycol, polypropylene glycol, dipropylene glycol n-butyl ether, sodium p-toluenesulfonate sodium xylene sulfonate and mixtures thereof.
WO2013/087286 (Unilever) discloses liquids formulations containing alkyl ether carboxylic acids, betaines, anionic surfactant, non-ionic surfactant for providing softening benefits.
WO2014/060235 (Unilever) discloses a laundry detergent composition comprising (a) nonionic surfactant, (b) anionic surfactant, (c) alkyl ether carboxylic acid or carboxylate salt thereof, and, (d) a polyglucosamine or a copolymer of glucosamine and N-acetylglucosamine; and to its use to soften fabrics.

SUMMARY OF THE INVENTION

We have found that a particular alkyl ether carboxylates when part of a binary system with particular lauryl ether sulphates have optical clarity without the need for an additional hydrotrope.
In one aspect, the present invention provides an aqueous liquid laundry detergent composition comprising:

(i) from 3 to 10 wt%, preferably from 4 to 8 wt%, of lauryl ether sulfate anionic surfactant, wherein the lauryl ether sulfate anionic surfactant has a mole average of 1 to 4 moles, preferably 2.5 to 3.5 moles of ethoxylation per mole of surfactant molecule;
(ii) from 3 to 10 wt%, preferably 4 to 8 wt%, of an alkyl ether carboxylic acid anionic surfactant of the following structure:

R₂-(OCH₂CH₂)_n-OCH₂-COOH,

wherein:
R₂ is selected from saturated and mono-unsaturated C10 to C18 linear or branched alkyl chains, preferably selected from: C12; C14; C16; and, C18 saturated linear alkyl chain, wherein n is selected from: 15 to 20, wherein the weight fraction of lauryl ether sulfate anionic surfactant/ alkyl ether carboxylic acid anionic surfactant is from 0.4 to 1.6, preferably 0.7 to 1.3;
(iii) at least 60 wt%, preferably at least 70 wt% water;
(iv) from 0 to 4 wt%, preferably 0 to 3 wt%, of an ethoxylated alcohol non-ionic surfactant, preferably selected from: C10 to C16 primary and secondary aliphatic alcohols ethoxylated with an average of from 6 to 10 moles of ethylene oxide per mole of alcohol, most preferably a C12 to C15 primary aliphatic alcohol with 7 to 9 moles of ethylene oxide per mole of alcohol, wherein the weight fraction of ethoxylated alcohol non-ionic surfactant/ (lauryl ether sulfate anionic surfactant + alkyl ether carboxylic acid anionic surfactant) is from 0 to 0.4, preferably 0 to 0.2;
(v) from 0 to 8 wt%, preferably 2 to 5 wt%, of an alkoxylated polyethylene imine, preferably ethoxylated polyethylene imine;
(vi) from 0 to 3 wt%, preferably 0.5 to 1.5 wt% of a terephthalate polyester soil release polymer; and,
(vii) a further anionic surfactant wherein the ratio of further anionic surfactant/(lauryl ether sulfate anionic surfactant + alkyl ether carboxylic acid anionic surfactant) is from 0 to 0.4, preferably 0 to 0.2.

The further anionic surfactant(s) (integer vii) may serve to control foaming.
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 from 1 g/L of an aqueous solution of the laundry detergent composition as defined in any one of the preceding claims; and,
(ii) allowing said aqueous laundry detergent solution to remain in contact with the textile for 10 minutes to 2 days then rinsing and drying the textile.

Preferably the clothes to be washed contain 0.1 to 2 wt% human sebum.
In the method aspects of the present invention the surfactant used is preferably as preferred for the composition aspects of the present invention.
Domestic methods are preferably conducted in a domestic washing machine or by hand washing. The temperature of the wash is preferably from 285 to 313K. The main wash time is preferably 5 to 30 minutes.
The textile is preferably an item of clothing, bedding or table cloth. Preferred items of clothing are cotton containing shirts, trousers, underwear and jumpers.
Notwithstanding the fact that the present invention is to negate the need for the presence of a hydrotrope one may be added for redundancy or another purpose. Another purpose, for example, would than we found in stabilizers for enzyme premixtures that are added to the detergent.
It is preferred that the aqueous liquid laundry detergent composition comprises less than or equal to 5 wt% (0 to 5 wt%), more preferably less than or equal to 0.2 wt% (0 to 0.2 wt%) of hydrotope selected from: ethylene glycol; 1,3 propanediol; 1,2 propanediol; tetramethylene glycol; pentamethylene glycol; hexamethylene glycol; 2,3-butane diol; 1,3 butanediol; diethylene glycol; triethylene glycol; polyethylene glycol; glycerol formal dipropylene glycol; polypropylene glycol; dipropylene glycol n-butyl ether; and, mixtures thereof. Preferably the hydrotope at the low level is selected from the group comprising: 1,2 propanediol; dipropylene glycol; polypropylene glycol; 2,3- butane diol; dipropylene glycol n-butyl ether; and, mixtures thereof.

DETAILED DESCRIPTION OF THE INVENTION

The surfactants of invention are preferably non-amine neutralized. Typical amine used to neutralise surfactants are alkyl ether carboxylic acid monoethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, monoamino hexanol, 2-[(2-methoxyethyl) methylamino]- ethanol, propanolamine, N-methylethanolamine, diethanolamine, monobutanol amine, isobutanolamine, monopentanol amine, I-amino-3-(2-methoxyethoxy)-2-propanol, 2-methyl-4-(methylamino)- 2-butanol, 6-amino-I-hexanol, heptaminol, isoetarine, norepinephrine, sphingosine, phenylpropanolamine and mixtures thereof.
The surfactants of invention are preferably neutralized with an aqueous solution of sodium hydroxide.
The surfactants are made from natural or synthetically derived chemicals, preferably they are naturally derived, most preferably the alkyl chains are obtained from renewable natural sources.
Weights of anionic surfactants are calculated as their protonated form.

Alkyl Ether Carboxylic Acid

Weights of alkyl ether carboxylic acid are calculated as the protonated form, R₂-(OCH₂CH₂)_n-OCH₂COOH. They may be used as salt version for example sodium salt, or amine salt. The integer n is the mole average of ethoxylation per mole of surfactant.
The alkyl chain may be linear or branched, preferably it is linear.
The alkyl chain may be aliphatic or contain one cis or trans double bond.
The alkyl chain is preferably selected from CH₃(CH₂)₁₁, CH₃(CH₂)₁₃, CH3(CH₂)₁₅, CH₃(CH₂)₁₇. A further example of an alkyl ether carboxylic acid is CH₃(CH₂)₇CH=CH(CH₂)₈-.
The alkyl ether carboxylic acid is most preferably selected from the structure:

CH₃(CH₂)₁₅(OCH₂CH₂)₂₀OCH₂COOH;

and,

CH₃(CH₂)₁₇(OCH₂CH₂)₂₀OCH₂COOH.
Alkyl ether carboxylic acid are available from Kao (Akypo®), Huntsman (Empicol®) and Clariant (Emulsogen®). The sodium salt of the alkyl ether carboxylate is most preferred.
An additional advantage of AEC incorporation is that it potentates the Ca and Mg salts of free fatty acids found in human sebum on clothes, converting them to useful soap surfactant. This allows use of less surfactant in the laundry liquid detergent for the same general detergency. In this aspect Palmitic and sapienic acid are particularly useful components of human sebum.

Lauryl Ether Sulfate

Weights of lauryl ether sulfate are calculated as the protonated form. The average number of moles of ethoxylation per mole of surfactant is preferably 1 to 4, most preferably 2.5 to 3.5. The sodium salt of the lauryl ether sulfate is preferred.

Non-ionic surfactant

The non-ionic surfactant is preferably an ethoxylated alcohol non-ionic surfactant, preferably selected from: C10 to C16 primary and secondary aliphatic alcohols ethoxylated with an average of from 6 to 10 moles of ethylene oxide per mole of alcohol, most preferably a C12 to C15 primary aliphatic alcohol with 7 to 9 moles of ethylene oxide per mole of alcohol, wherein the weight fraction of ethoxylated alcohol non-ionic surfactant/ (lauryl ether sulfate anionic surfactant + alkyl ether carboxylic acid anionic surfactant) is from 0 to 0.4, preferably 0 to 0.2;
Preferably the alkyl chain is linear.

Further Surfactant

The aqueous liquid laundry detergent may comprises from 0 to 4 wt% of further surfactants, for example those described in "Surface Active Agents" Vol. 1, by Schwartz & Perry, Interscience 1949, Vol. 2 by Schwartz, Perry & Berch, Interscience 1958, in the current edition of "McCutcheon's Emulsifiers and Detergents" published by Manufacturing Confectioners Company or in "Tenside-Taschenbuch", H. Stache, 2nd Edn., Carl Hauser Verlag, 1981 or in Anionic Surfactants: Organic Chemistry edited by Helmut W. Stache (Marcel Dekker 1996).
Examples of suitable further anionic detergent compounds are; alkyl sulphates, especially those obtained by sulphating linear or branched C₈ to C₁₈ alcohols; soaps; alkyl (preferably methyl) ester sulphonates, and mixtures thereof. Soaps are particularly preferred, preferably from 0.5 to 2wt%.
Linear alkyl benzene sulphonates are preferably present in the aqueous liquid laundry detergent composition at a level from 0 to 1 wt% and ideally the composition is substantially devoid of linear alkyl benzene sulfonate.

Alkoxylate Polyethylene Imine

The alkoxylated polyethyelene imine comprises a polyethyleneimine backbone wherein the modification of the polyethyleneimine backbone is intended to leave the polymer without quaternisation. Such materials may be represented as PEI(X)YAO where X represents the molecular weight of the unmodified PEI and Y represents the average moles of alkoxylation (AO) per available NH in the unsubstituted polyethyleneimine backbone. Y is preferably from 7 to 40 more preferably it is in the range of 16 to 26, most preferably 18 to 22. X is selected to be from about 300 to about 10000 weight average molecular weight and is preferably about 600.
The alkoxylation is preferably selected from ethoxylation or propoxylation, or a combination of the two, Ethoxylation is most preferred. The alkoxy chains may be capped with groups selected from: H; CH₃; SO₃ ^-; CH₂COO^-; PO₃ ^2-; C₂H₅; n-propyl, i-propyl; n-butyl; t-butyl; and, sulfosuccinate, most preferably H.
Most preferably the alkoxylated PEI is PEI(600)20EO.

Terephthalate Polyester Soil Release Polymer

Terephthalate Polyester Soil Release Polymer comprise polymers of aromatic dicarboxylic acids and alkylene glycols (including polymers containing polyalkylene glycols), as described in WO2009/153184 , EP2692842 and WO2014/019903 .
Examples of Terephthalate Polyester Soil Release Polymer are the REPEL-O-TEX® line of polymers supplied by Rhodia, including REPEL-O-TEX® SRP6 and REPEL-O-TEX® SF-2. Other suitable soil release polymers include TexCare® polymers, including TexCare® SRA-100, TexCare® SRA-300, TexCare® SRN-100, TexCare® SRN-170, TexCare® SRN-240, TexCare® SRN-300, and TexCare® SRN-325, all supplied by Clariant.
Preferred structure are -[(Z)_a-O-OC-Ar-CO-]_b and (Z)_a-O-OC-[Ar-CO-O-C₃H₆-O-OC]_b-Ar-COO-(Z)_a, where Ar is selected from 1,4 substituted phenylene and 1,3 substituted phenylene substituted in the 5 position with a sulphonates (SO₃ ^-) group; Z is selected from ethoxy;propoxy; and mixtures of ethoxy and propoxy; a is from 5 to 100 and b from 2 to 40. C₃H₆ is i-propyl.
The alkoxy chains are capped with groups selected from H; CH₃; SO₃ ^-; CH₂COO^-; PO₃ ^2-; C₂H₅; n-propyl, i-propyl; n-butyl; t-butyl; and, sulfosuccinate.
Most preferably the Terephthalate Polyester Soil Release Polymer is:
wherein c is from 4 to 9; d is from 1 to 3; e is from 40 to 50.

Polymers

The composition may comprise one or more further polymers. Examples are carboxymethylcellulose, poly (ethylene glycol), poly(vinyl alcohol), polycarboxylates such as polyacrylates, maleic/acrylic acid copolymers and lauryl methacrylate/acrylic acid copolymers. Co-polymers as described in WO2014/082955 (Unilever ) may be present. Polymers present to prevent dye deposition may be present, for example poly(vinylpyrrolidone), poly(vinylpyridine-N-oxide), and poly(vinylimidazole).
Such polymers are preferably present at levels of less then 0.5wt%.
The composition is preferably devoid of silicone polymers and polymers bearing quaternised N groups.

Builders and Sequestrants

The detergent compositions may also optionally contain relatively low levels of organic detergent builder or sequestrant material. Examples include the alkali metal, citrates, succinates, malonates, carboxymethyl succinates, carboxylates, polycarboxylates and polyacetyl carboxylates. Specific examples include sodium, potassium and lithium salts of oxydisuccinic acid, mellitic acid, benzene polycarboxylic acids, ethylene diamine tetra-acetic acid, diethylenetriamine-pentaacetic acid, alkyl- or alkenylsuccinic acid, nitrilotriacetic acid, and citric acid. Other examples are DEQUEST™, organic phosphonate type sequestering agents sold by Monsanto and alkanehydroxy phosphonates.
Other suitable organic builders include the higher molecular weight polymers and copolymers known to have builder properties. For example, such materials include appropriate polyacrylic acid, polymaleic acid, and polyacrylic/polymaleic acid copolymers and their salts, such as those sold by BASF under the name SOKALAN™.
If utilized, the aqueous liquid laundry detergent formunation comprise from 0.1% to 2.0 wt% builder and sequesterant material. Citrate is most preferred.
The pH of the formulation is preferably from 6.5 to 8.5, most preferably 6.8 to 7.5. pH may be obtained by the addition of an alkali, such as NaOH or an amine.

Shading Dye

Dyes are described in Color Chemistry Synthesis, Properties and Applications of Organic Dyes and Pigments, (H Zollinger, Wiley VCH, Zurich, 2003) and, Industrial Dyes Chemistry, Properties Applications. (K Hunger (ed), Wiley-VCH Weinheim 2003).
Shading Dyes for use in laundry detergents preferably have an extinction coefficient at the maximum absorption in the visible range (400 to 700nm) of greater than 5000 L mol^-1 cm^-1, preferably greater than 10000 L mol^-1 cm^-1. The dyes are blue or violet in colour.
Preferred shading dye chromophores are azo, azine, anthraquinone, and triphenylmethane. Preferred mono-azo dyes contain a heterocyclic ring and are most preferably thiophene dyes. The mono-azo 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:

and,
Azine dye are preferably selected from sulphonated phenazine dyes and cationic phenazine dyes. Preferred examples are acid blue 98, acid violet 50, dye with CAS-No 72749-80-5, acid blue 59.
The shading dye is present is present in the composition in range from 0.0001 to 0.5 wt %, preferably 0.001 to 0.1 wt%. Depending upon the nature of the shading dye there are preferred ranges depending upon the efficacy of the shading dye which is dependent on class and particular efficacy within any particular class. As stated above the shading dye is a blue or violet shading dye.
A mixture of shading dyes may be used.
The shading dye is most preferably 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 mol% of the N-H groups in the polyethylene imine are replaced with iso-propyl alcohol groups by propoxylation. Preferably the polyethylene imine before reaction with the dye and the propoxylation has a molecular weight of 600 to 1800.
An example structure of a preferred reactive anthraquinone covalently attached to a propoxylated polyethylene imine 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 blue103; Reactive blue114; Reactive blue117; Reactive blue125; Reactive blue141; Reactive blue142; 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 246; 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 Colour Index (Society of Dyers and Colourists/American Association of Textile Chemists and Colorists) classification.

Protease Enzyme

Protease enzymes hydrolyse bonds within peptides and proteins, in the laundry context this leads to enhanced removal of protein or peptide containing stains. Examples of suitable proteases families include aspartic proteases; cysteine proteases; glutamic proteases; aspargine peptide lyase; serine proteases and threonine proteases. Such protease families are described in the MEROPS peptidase database (http://merops.sanger.ac.uk/). Serine proteases are preferred. Subtilase type serine proteases are more preferred. The term "subtilases" refers to a sub-group of serine protease 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 subgroup of proteases characterized by having a serine in the active site, which forms a covalent adduct with the substrate. The subtilases may be divided into 6 subdivisions, i.e. the Subtilisin family, the Thermitase family, the Proteinase K family, the Lantibiotic peptidase family, the Kexin family and the Pyrolysin family.
Examples of subtilases are those derived from Bacillus such as Bacillus lentus, B. alkalophilus, B. subtilis, B. amyloliquefaciens, Bacillus pumilus and Bacillus gibsonii described in; US7262042 and WO09/021867 , and subtilisin lentus, subtilisin Novo, subtilisin Carlsberg, Bacillus licheniformis, subtilisin BPN', subtilisin 309, subtilisin 147 and subtilisin 168 described in WO89/06279 and protease PD138 described in ( WO93/18140 ). Other useful proteases may be those described in WO92/175177 , WO01/016285 , WO02/026024 and WO02/016547 . Examples of trypsin-like proteases are trypsin (e.g. of porcine or bovine origin) and the Fusarium protease described in WO89/06270 , WO94/25583 and WO05/040372 , and the chymotrypsin proteases derived from Cellumonas described in WO05/052161 and WO05/052146 .
Further Examples of useful proteases are the variants described in: WO92/19729 , WO96/034946 , WO98/201 15 , WO98/201 16 , WO99/01 1768 , WO01/44452 , WO03/006602 , WO04/03186 , WO04/041979 , WO07/006305 , WO1 1/036263 , WO1 1/036264 , especially the variants with substitutions in one or more of the following positions: 3, 4, 9, 15, 27, 36, 57, 68, 76, 87, 95, 96, 97, 98, 99, 100, 101 , 102, 103, 104, 106, 1 18, 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 using the BPN' numbering. More preferred the subtilase variants may comprise the mutations: S3T, V4I, S9R, A15T, K27R, *36D, V68A, N76D, N87S,R, *97E, A98S, S99G,D,A, S99AD, S101 G,M,R S103A, V104I,Y,N, S106A, G1 18V,R, H120D,N, N123S, S128L, P129Q, S130A, G160D, Y167A, R170S, A194P, G195E, V199M, V205I, L217D, N218D, M222S, A232V, K235L, Q236H, Q245R, N252K, T274A (using BPN' numbering).
Most preferably the protease is a subtilisins (EC 3.4.21.62).
Examples of subtilases are those derived from Bacillus such as Bacillus lentus, B. alkalophilus, B. subtilis, B. amyloliquefaciens, Bacillus pumilus and Bacillus gibsonii described in; US7262042 and WO09/021867 , and subtilisin lentus, subtilisin Novo, subtilisin Carlsberg, Bacillus licheniformis, subtilisin BPN', subtilisin 309, subtilisin 147 and subtilisin 168 described in WO89/06279 and protease PD138 described in ( WO93/18140 ). Preferably the subsilisin is derived from Bacillus, preferably Bacillus lentus, B. alkalophilus, B. subtilis, B. amyloliquefaciens, Bacillus pumilus and Bacillus gibsonii as described in US 6,312,936 BI, US 5,679,630 , US 4,760,025 , US7,262,042 and WO09/021867 . Most preferably the subtilisin is derived from Bacillus gibsonii or Bacillus Lentus.
Suitable commercially available protease enzymes include those sold under the trade names names Alcalase®, Blaze®; DuralaseTm, DurazymTm, Relase®, Relase® Ultra, Savinase®, Savinase® Ultra, Primase®, Polarzyme®, Kannase®, Liquanase®, Liquanase® Ultra, Ovozyme®, Coronase®, Coronase® Ultra, Neutrase®, Everlase® and Esperase® all could be sold as Ultra® or Evity® (Novozymes A/S).
Those sold under the tradename Maxatase®, Maxacal®, Maxapem®, Properase®, Purafect®, Purafect Prime®, Purafect Ox®, FN3®, FN4®, Excellase® and Purafect OXP® by Genencor International.
Those sold under the tradename Maxatase®, Maxacal®, Maxapem®, Purafect®, Purafect Prime®, PreferenzTm, Purafect MA®, Purafect Ox®, Purafect OxP®, Puramax®, Properase®, EffectenzTm, FN2®, FN3®, FN4®, Excellase®, Opticlean® and Optimase® (Danisco/DuPont), Axapem™ (Gist-Brocases N.V.),
Those available from Henkel/ Kemira, namely BLAP (sequence shown in Figure 29 of US 5,352,604 with the following mutations S99D + SIOI R + 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 (Bacillus alkalophilus subtilisin with mutations A230V + S256G + S259N) from Kao.
Inclusion of protease in the formulation enhances cleaning.

Further Enzymes

One or more further enzymes are preferred present in a laundry composition of the invention and when practicing a method of the invention.
Preferably the level of each enzyme in the laundry composition of the invention is from 0.0001 wt% to 0.1 wt% protein.
Preferably the further enzyme is selected from: alpha-amylases; lipases; and, cellulases.
Suitable lipases include those of bacterial or fungal origin. Chemically modified or protein engineered mutants are included. Examples of useful lipases include lipases from Humicola (synonym Thermomyces), e.g. from H. lanuginosa (T. lanuginosus) as described in EP 258 068 and EP 305 216 or from H. insolens as described in WO 96/13580 , a Pseudomonas lipase, e.g. from P. alcaligenes or P. pseudoalcaligenes ( EP 218 272 ), P. cepacia ( EP 331 376 ), P. stutzeri ( GB 1,372,034 ), P. fluorescens, Pseudomonas sp. strain SD 705 ( WO 95/06720 and WO 96/27002 ), P. wisconsinensis ( WO 96/12012 ), a Bacillus lipase, e.g. from B. subtilis (Dartois et al. (1993), Biochemica et Biophysica Acta, 1131, 253-360), B. stearothermophilus ( JP 64/744992 ) or B. pumilus ( WO 91/16422 ).
Other examples are lipase variants such as those described in WO 92/05249 , WO 94/01541 , EP 407 225 , EP 260 105 , WO 95/35381 , WO 96/00292 , WO 95/30744 , WO 94/25578 , WO 95/14783 , WO 95/22615 , WO 97/04079 and WO 97/07202 , and WO 00/60063 .
Preferred commercially available lipase enzymes include Lipolase™ and Lipolase Ultra™, Lipex™ and Lipoclean™ (Novozymes A/S).
The method of the invention may be carried out in the presence of phospholipase classified as EC 3.1.1.4 and/or EC 3.1.1.32. As used herein, the term phospholipase is an enzyme which has activity towards phospholipids.
Phospholipids, such as lecithin or phosphatidylcholine, consist of glycerol esterified with two fatty acids in an outer (sn-1) and the middle (sn-2) positions and esterified with phosphoric acid in the third position; the phosphoric acid, in turn, may be esterified to an amino-alcohol. Phospholipases are enzymes which participate in the hydrolysis of phospholipids. Several types of phospholipase activity can be distinguished, including phospholipases A₁ and A₂ which hydrolyze one fatty acyl group (in the sn-1 and sn-2 position, respectively) to form lysophospholipid; and lysophospholipase (or phospholipase B) which can hydrolyze the remaining fatty acyl group in lysophospholipid. Phospholipase C and phospholipase D (phosphodiesterases) release diacyl glycerol or phosphatidic acid respectively.
The method of the invention may be carried out in the presence of cutinase classified in EC 3.1.1.74. The cutinase used according to the invention may be of any origin. Preferably cutinases are of microbial origin, in particular of bacterial, of fungal or of yeast origin.
Suitable amylases (alpha and/or beta) include those of bacterial or fungal origin. Chemically modified or protein engineered mutants are included. Amylases include, for example, alpha-amylases obtained from Bacillus, e.g. a special strain of B. licheniformis, described in more detail in GB 1,296,839 , or the Bacillus sp. strains disclosed in WO 95/026397 or WO 00/060060 . Commercially available amylases are Duramyl™, Termamyl™, Termamyl Ultra™, Natalase™, Stainzyme™, Fungamyl™ and BAN™ (Novozymes A/S), Rapidase™ and Purastar™ (from Genencor International Inc.).
Suitable cellulases include those of bacterial or fungal origin. Chemically modified or protein engineered mutants are included. Suitable cellulases include cellulases from the genera Bacillus, Pseudomonas, Humicola, Fusarium, Thielavia, Acremonium, e.g. the fungal cellulases produced from Humicola insolens, Thielavia terrestris, Myceliophthora thermophila, and Fusarium oxysporum disclosed in US 4,435,307 , US 5,648,263 , US 5,691,178 , US 5,776,757 , WO 89/09259 , WO 96/029397 , and WO 98/012307 . Commercially available cellulases include Celluzyme™, Carezyme™, Celluclean™, Endolase™, Renozyme™ (Novozymes A/S), Clazinase™ and Puradax HA™ (Genencor International Inc.), and KAC-500(B)™ (Kao Corporation). Celluclean™ is preferred. Suitable peroxidases/oxidases include those of plant, bacterial or fungal origin. Chemically modified or protein engineered mutants are included. Examples of useful peroxidases include peroxidases from Coprinus, e.g. from C. cinereus, and variants thereof as those described in WO 93/24618 , WO 95/10602 , and WO 98/15257 . Commercially available peroxidases include Guardzyme™ and Novozym™ 51004 (Novozymes A/S).
Further enzymes suitable for use are discussed in WO2009/087524 , WO2009/090576 , WO2009/107091 , WO2009/111258 , and WO2009/148983 .

Enzyme Stabilizers

Any enzyme present in the composition may be stabilized using conventional stabilizing agents, e.g., 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 e.g., WO 92/19709 and WO 92/19708 .
Where alkyl groups are sufficiently long to form branched or cyclic chains, the alkyl groups encompass branched, cyclic and linear alkyl chains. The alkyl groups are preferably linear or branched, most preferably linear.

Fluorescent Agent

The composition preferably comprises a fluorescent agent (optical brightener). Fluorescent agents are well known and many such fluorescent agents are available commercially. Usually, these fluorescent agents are supplied and used in the form of their alkali metal salts, for example, the sodium salts.
Preferred classes of fluorescer are: Di-styryl biphenyl compounds, e.g. Tinopal (Trade Mark) CBS-X, Di-amine stilbene di-sulphonic acid compounds, e.g. Tinopal DMS pure Xtra and Blankophor (Trade Mark) HRH, and Pyrazoline compounds, e.g. Blankophor SN.
Preferred fluorescers are: sodium 2 (4-styryl-3-sulphophenyl)-2H-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' disulophonate, disodium 4,4'-bis{[(4-anilino-6-morpholino-1,3,5-triazin-2-yl)]amino}stilbene-2-2'disulphonate, and disodium 4,4'-bis(2-sulphostyryl)biphenyl.
The total amount of the fluorescent agent or agents used in the composition is preferably from 0.0001 to 0.5 wt %, more preferably 0.005 to 2 wt %, most preferably 0.05 to 0.25 wt %.
The aqueous solution used in the method has a fluorescer present. The fluorescer is present in the aqueous solution used in the method preferably in the range from 0.0001 g/l to 0.1 g/l, more preferably 0.001 to 0.02 g/l.

Perfume

The composition comprises a perfume. The perfume is preferably in the range from 0.001 to 3 wt %, more preferably 0.05 to 0.5 wt%, most preferably from 0.1 to 1 wt %. Many suitable examples of perfumes are provided in the CTFA (Cosmetic, Toiletry and Fragrance Association) 1992 International Buyers Guide, published by CFTA Publications and OPD 1993 Chemicals Buyers Directory 80th Annual Edition, published by Schnell Publishing Co.
Preferably the perfume comprises at least one note (compound) from: alpha-isomethyl ionone, benzyl salicylate; citronellol; coumarin; hexyl cinnamal; linalool; Pentanoic acid, 2-methyl-, ethyl ester; octanal; benzyl acetate; 1,6-octadien-3-ol, 3,7-dimethyl-, 3-acetate; cyclohexanol, 2-(1,1-dimethylethyl)-, 1-acetate; delta-damascone; beta-ionone; verdyl acetate; dodecanal; hexyl cinnamic aldehyde; cyclopentadecanolide; benzeneacetic acid, 2-phenylethyl ester;amyl salicylate; beta-caryophyllene; ethyl undecylenate; geranyl anthranilate; alpha-irone; beta-phenyl ethyl benzoate; alpa-santalol; cedrol; cedryl acetate; cedry formate; cyclohexyl salicyate; gamma-dodecalactone; and, beta phenylethyl phenyl acetate.
Useful components of the perfume include materials of both natural and synthetic origin. They include single compounds and mixtures. Specific examples of such components may be found in the current literature, e.g., in Fenaroli's Handbook of Flavor Ingredients, 1975, CRC Press; Synthetic Food Adjuncts, 1947 by M. B. Jacobs, edited by Van Nostrand; or Perfume and Flavor Chemicals by S. Arctander 1969, Montclair, N.J. (USA).
It is commonplace for a plurality of perfume components to be present in a formulation. In the compositions of the present invention it is envisaged that there will be four or more, preferably five or more, more preferably six or more or even seven or more different perfume components.
In perfume mixtures preferably 15 to 25 wt% are 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 oils, linalool, linalyl acetate, lavender, dihydromyrcenol, rose oxide and cis-3-hexanol.
The International Fragrance Association has published a list of fragrance ingredients (perfumes) in 2011: (http://www.ifraorg.org/en-us/ingredients#.U7Z4hPIdWzk).
The Research Institute for Fragrance Materials provides a database of perfumes (fragrances) with safety information.
Perfume top note may be used to cue the whiteness and brightness benefit of the invention.
Some or all of the perfume may be encapsulated, typical perfume components which it is advantageous to encapsulate, include those with a relatively low boiling point, preferably those with a boiling point of less than 300, preferably 100-250 Celsius. It is also advantageous to encapsulate perfume components which have a low CLog P (ie. those which will have a greater tendency to be partitioned into water), preferably with a CLog P of less than 3.0. These materials, of relatively low boiling point and relatively low CLog P have been called the "delayed blooming" perfume ingredients and include one or more of the following materials: allyl caproate, amyl acetate, amyl propionate, anisic aldehyde, anisole, benzaldehyde, benzyl acetate, benzyl acetone, benzyl alcohol, benzyl formate, benzyl iso valerate, benzyl propionate, beta gamma hexenol, camphor gum, laevo-carvone, d-carvone, cinnamic alcohol, cinamyl formate, cis-jasmone, cis-3-hexenyl acetate, cuminic alcohol, cyclal c, dimethyl benzyl carbinol, dimethyl benzyl carbinol acetate, ethyl acetate, ethyl aceto acetate, ethyl amyl ketone, ethyl benzoate, ethyl butyrate, ethyl hexyl ketone, ethyl phenyl acetate, eucalyptol, eugenol, fenchyl acetate, flor acetate (tricyclo decenyl acetate), frutene (tricyclco decenyl propionate), geraniol, hexenol, hexenyl acetate, hexyl acetate, hexyl formate, hydratropic alcohol, hydroxycitronellal, indone, isoamyl alcohol, iso menthone, isopulegyl acetate, isoquinolone, ligustral, linalool, linalool oxide, linalyl formate, menthone, menthyl acetphenone, methyl amyl ketone, methyl anthranilate, methyl benzoate, methyl benyl acetate, methyl eugenol, methyl heptenone, methyl heptine carbonate, methyl heptyl ketone, methyl hexyl ketone, methyl phenyl carbinyl acetate, methyl salicylate, methyl-n-methyl anthranilate, nerol, octalactone, octyl alcohol, p-cresol, p-cresol methyl ether, p-methoxy acetophenone, p-methyl acetophenone, phenoxy ethanol, phenyl acetaldehyde, phenyl ethyl acetate, phenyl ethyl alcohol, phenyl ethyl dimethyl carbinol, prenyl acetate, propyl bornate, pulegone, rose oxide, safrole, 4-terpinenol, alpha-terpinenol, and /or viridine. It is commonplace for a plurality of perfume components to be present in a formulation. In the compositions of the present invention it is envisaged that there will be four or more, preferably five or more, more preferably six or more or even seven or more different perfume components from the list given of delayed blooming perfumes given above present in the perfume.
Another group of perfumes with which the present invention can be applied are the socalled 'aromatherapy' materials. These include many components also used in perfumery, including components of essential oils such as Clary Sage, Eucalyptus, Geranium, Lavender, Mace Extract, Neroli, Nutmeg, Spearmint, Sweet Violet Leaf and Valerian.
It is preferred that the laundry treatment composition does not contain a peroxygen bleach, e.g., sodium percarbonate, sodium perborate, and peracid.
The indefinite article "a" or "an" and its corresponding definite article "the" as used herein means at least one, or one or more, unless specified otherwise.
A most preferred aspect of the invention, the at least 60 wt% containing composition comprises from 4 to 6 wt% of lauryl ether sulfate anionic surfactant with a mole average of 2.5 to 3.5 moles of ethoxylation per mole surfactant; from 4 to 6 wt% of an stearyl ether carboxylic acid anionic surfactant with a mole average of 15 to 20 moles of ethoxylation per mole surfactant; from 0 to 2 wt% of an C12 to C15 primary aliphatic alcohol with 7 to 9 moles of ethylene oxide per mole of alcohol non-ionic surfactant.
The liquid laundry detergent composition may be present in a water-soluble unit dose article. In such an embodiment, the water-soluble unit dose article comprises at least one water-soluble film shaped such that the unit-dose article comprises at least one internal compartment surrounded by the water-soluble film. The at least one compartment comprises the liquid laundry detergent composition. The water-soluble film is sealed such that the liquid laundry detergent composition does not leak out of the compartment during storage. However, upon addition of the water-soluble unit dose article to water, the water-soluble film dissolves and releases the contents of the internal compartment into the wash liquor.

Experimental

Aqueous laundry liquid detergent were made, as outlined in the table below. The pH of the liquid was adjusted to 7. The optical absorbance was measures in a 1cm cell at 470nm and is also reported in the table. Higher absorbance values indicate scattering effects dye to incomplete solubilisation of the surfactant mix.

	Ref 1	Inv 1	Ref 2	Inv 2
Linear alkyl benzene sulfonate	5		4
Stearyl ether carboxylate with 20 moles equivalents of ethoxylation		5		4
Lauryl ether sulfate with 3 mole equivalent of ethoxylation	5	5	4	4
C12-C15 linear aliphatic alcohol with 7 moles of ethoxylation			2	2
water	remainder
Absorbance	0.382	0.035	0.181	0.038

The inventive formulation Inv 1 and Inv 2 containing the alkyl ether carboxylic acid have lower absorbance than the comparative reference formulations, indicating better solubilisation of the surfactant mix.

Claims

An aqueous liquid laundry detergent composition comprising:
(i) from 3 to 10 wt% of lauryl ether sulfate anionic surfactant, wherein the lauryl ether sulfate anionic surfactant has a mole average of 1 to 4 moles of ethoxylation per mole surfactant molecule;

(ii) from 3 to 10 wt% of an alkyl ether carboxylic acid anionic surfactant of the following structure:

R₂-(OCH₂CH₂)_n-OCH₂-COOH,

wherein:
R₂ is selected from saturated and mono-unsaturated C10 to C18 linear or branched alkyl chains, preferably selected from: C12; C14; C16; and, C18 saturated linear alkyl chain, wherein n is selected from: 15 to 20, and wherein the weight fraction of lauryl ether sulfate anionic surfactant/ alkyl ether carboxylic acid anionic surfactant is from 0.4 to 1.6;

(iii) at least 60 wt% water;

(iv) from 0 to 4 wt% of an ethoxylated alcohol non-ionic surfactant, wherein the weight fraction of ethoxylated alcohol non-ionic surfactant/ (lauryl ether sulfate anionic surfactant + alkyl ether carboxylic acid anionic surfactant) is from 0 to 0.4;

(v) from 0 to 8 wt% of an alkoxylated polyethylene imine;

(vi) from 0 to 3 wt% of a terephthalate polyester soil release polymer; and,

(vii) a further anionic surfactant wherein the ratio of further anionic surfactant/(lauryl ether sulfate anionic surfactant + alkyl ether carboxylic acid anionic surfactant) is from 0 to 0.4, preferably 0 to 0.2.
An aqueous liquid laundry detergent composition according to claim 1, wherein the lauryl ether sulfate anionic surfactant has a mole average of from 2.5 to 3.5 of ethoxylation.
An aqueous liquid laundry detergent composition according to claim 1 or 2, wherein R₂ is selected from a C12, C14, C16, and C18 saturated linear alkyl chain.
An aqueous liquid laundry detergent composition according to any one of the preceding claims, wherein the weight fraction of lauryl ether sulfate anionic surfactant/ alkyl ether carboxylic acid anionic surfactant is from 0.7 to 1.3.
An aqueous liquid laundry detergent composition according to any one of the preceding claims, wherein the ethoxylated alcohol non-ionic surfactant is a C12 to C16 primary aliphatic alcohol with 7 to 9 moles of ethylene oxide per mole of alcohol.
An aqueous liquid laundry detergent composition according to any one of the preceding claims, wherein the weight fraction of ethoxylated alcohol non-ionic surfactant/ (lauryl ether sulfate anionic surfactant + alkyl ether carboxylic acid anionic surfactant) is from 0 to 0.2.
An aqueous liquid laundry detergent composition according to claim 1, wherein the ratio of further anionic surfactant/(lauryl ether sulfate anionic surfactant + alkyl ether carboxylic acid anionic surfactant) is from 0 to 0.2.
A domestic method of treating a textile, the method comprising the steps of:
(i) treating a textile with from 1 g/L of an aqueous solution of the laundry detergent composition as defined in any one of the preceding claims; and,

(ii) allowing said aqueous laundry detergent solution to remain in contact with the textile for 10 minutes to 2 days then rinsing and drying the textile.