EP2791308A1

EP2791308A1 - Laundry compositions

Info

Publication number: EP2791308A1
Application number: EP12781306.1A
Authority: EP
Inventors: Martin Charles Crossman
Original assignee: Unilever PLC; Unilever NV
Current assignee: Unilever PLC; Unilever NV
Priority date: 2011-12-12
Filing date: 2012-10-31
Publication date: 2014-10-22
Anticipated expiration: 2032-10-31
Also published as: WO2013087287A1; ES2565528T3; CN103975049A; AR089147A1; BR112014013668B1; EP2791308B1; WO2013087284A1; BR112014013668A2; ZA201403695B

Abstract

The present invention relates to a laundry liquid detergent composition comprising (a) nonionic surfactant which comprises an alcohol ethoxylate, (b) anionic surfactant, (c) alkyl ether carboxylic acid or carboxylate salt thereof and (d) a cationic polysaccharide polymer.

Description

LAUNDRY COMPOSITIONS

FIELD OF THE INVENTION This invention relates to a laundry composition. More particularly, the invention is directed to a liquid laundry detergent composition.

BACKGROUND OF THE INVENTION Textile fabrics, including clothes, have traditionally been cleaned with laundry detergents. After cleaning, fabrics can often feel harsh and they will wear and lose colour over repeat wash cycles. To prevent the drawbacks of fabrics feeling harsh after cleaning and those experienced by multiple wash cycles, technologies have been developed to increase the softness of fabrics, including rinse-added conditioner compositions and softening systems added to the detergent composition.

One such formulation comprises a cationic polymer and anionic surfactant. Such compositions are known from W010/072628 A1 which discloses particular combinations of cationic polymers, anionic and nonionic surfactants and fatty acids, with a particular ratio of nonionic surfactant to fatty acid for improved stability.

However such formulations do not show the required formulation stability at pH 6.2 to 9. There is thus a need for liquid laundry detergent compositions that have improved stability at this pH range.

SUMMARY OF THE INVENTION

The invention is directed to a laundry liquid detergent composition comprising:- (a) from 2 to 40 wt.% nonionic surfactant, comprising an alcohol ethoxylate;

(b) from 4 to 40 wt.% anionic surfactant;

(c) from 1 to 12 wt.% alkyl ether carboxylic acid or carboxylate salt thereof; and,

(d) from 0.1 to 1 .5 wt.% cationic polysaccharide polymer.

Preferably the detergent composition has a pH of from 6.2 to 9, more preferably from pH 6.5 to 8.5, for example from pH 6.5 to 8. Preferably the alkyl ether carboxylic acid or carboxylate salt thereof is present at a level of from 1 to 10 wt.%, more preferably at a level of from 2 to 7.5 wt.%.

Preferred alkyl ether carboxylic acid or carboxylate salt are depicted by formula 1 :

Formula 1

wherein R denotes a saturated or unsaturated C6-C22 alkyl chain; R¹ and R² are either both hydrogen; or R¹ is hydrogen and R² is CH₃; or R¹ is CH₃ and R² is hydrogen; R³ is hydrogen, or a solubilising cation such as sodium, potassium, ammonium or substituted ammonium; and, n is a number from 2 to 20, preferably 3 to 12, more preferably 3 to 10, which denotes the number of repeat units.

Preferred alkyl ether carboxylic acids or carboxylate salts thereof have a Cs-Cis alkyl chain with between 2 to 20, more preferably between 3 to 12, even more preferably between 3 to 10 glycol repeat units, wherein the glycol repeat units are selected from ethylene glycol, propylene glycol or mixtures thereof. By this is meant that the molecule of formula 1 may contain mixtures of polyethylene glycol (also known as ethylene oxide) and polypropylene glycol (also known as propylene oxide) repeat units.

A preferred level of the cationic polysaccharide polymer is from 0.1 to 1 wt.%.

Preferred cationic polysaccharide polymers are cationic guar and cationic cellulose polymers. Particularly preferred is hydroxy ether cellulose that is modified by incorporation of cationic groups (i.e. quaternised hydroxy ethyl cellulose).

Optionally, but preferably, the composition further comprises an ingredient selected from, shading dye, enzyme, an antiredeposition polymer, a dye transfer inhibiting polymer, builder, sequestrant, sunscreen and/or soil release polymer. DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term "comprising" means including, made up of, composed of, consisting and/or consisting essentially of. All percentages quoted are wt.% based on total amount in the laundry composition unless otherwise stated.

The invention is directed to laundry compositions containing alkyl ether carboxylic acid or carboxylate salt thereof, a cationic polysaccharide polymer, a nonionic surfactant which comprises an alcohol ethoxylate, and an anionic surfactant. The composition displays improved stability over the prior art at pH levels of 6.2 to 9.

Form of the Invention

The invention may take any of a number of forms, particularly those that are intended as laundry main wash products. It can take the form of a laundry treatment agent for the main wash, which may be dilutable or non-dilutable. The laundry treatment agent may for example be an isotropic liquid, or a surfactant- structured liquid. The invention may also take the form of a viscous liquid, for example a gel. Particularly preferred forms of this invention include combination detergent/softener products to provide "softening in the wash".

Preferably the detergent composition has a pH of from 6.2 to 9, more preferably from pH 6.5 to 8.5, for example from pH 6.5 to 8. Alkyl Ether Carboxylic Acid

The composition comprises 1 to 12 wt.% alkyl ether carboxylic acid or carboxylate salt thereof.

The alkyl ether carboxylic acid/carboxylate (AEC) is usually derived from a fatty alcohol which is alkoxylated, usually with ethylene glycol and/or propylene glycol, a carboxylic acid is then introduced to the material to form the alkyl ether carboxylic acid.

Preferably the alkyl ether carboxylic acid or carboxylate salt thereof is present at a level of from 1 to 10 wt.%, more preferably at a level of from 2 to 7.5 wt.%.

Formula 1

wherein R denotes a saturated or unsaturated C6-C22 alkyl chain; R¹ and R² are either both hydrogen (in which case the repeat unit is ethylene glycol known as (EO) for short); or R¹ is hydrogen and R² is CH₃; or R¹ is CH₃ and R² is hydrogen (in which case the repeat unit is propylene glycol, known as (PO) for short); R³ is hydrogen (in which case it is an alkyl ether carboxylic acid), or a solubilising cation such as sodium, potassium, ammonium or substituted ammonium (in which case it is an alkyl ether carboxylate salt); and, n is a number from 2 to 20, preferably 3 to 12, more preferably 3 to 10, which denotes the number of repeat units.

Preferred alkyl ether carboxylic acids or carboxylate salts thereof have a Cs-Cis alkyl chain with between 2 to 20, more preferably between 3 to 12, even more preferably between 3 to 10 glycol repeat units, wherein the glycol repeat units are selected from ethylene glycol, propylene glycol or mixtures thereof. By this is meant that the molecule of formula 1 may contain mixtures of polyethylene glycol (also known as ethylene oxide) and polypropylene glycol (also known as propylene oxide) repeat units. When in the form of an alkyl ether carboxylate salt, a preferred salt is sodium. Examples of suitable materials are oleyl alkyl ether (8EO) carboxylic acid, or laureth-5 carboxylic acid (5EO), and the sodium salts thereof.

Surfactants

The liquid detergent composition comprises nonionic surfactant, and anionic surfactant. The nonionic surfactant component comprises alcohol ethoxylate.

The alcohol ethoxylates are formed from the reaction of primary or secondary alcohols with ethylene oxide. Typicially an aliphatic Cs to Cis primary or secondary linear or branched alcohol is reacted with ethylene oxide in the required molar amount to produce the alcohol ethoxylate. Preferred alcohol ethoxylates have from 2 to 40, preferably from 3 to 30, more preferably from 5 to 20 ethylene oxide units attached to the aliphatic chain. The surfactants may be chosen from the surfactants 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 .

Preferably the surfactants used are saturated.

Suitable nonionic detergent compounds which may be used include, in particular, the reaction products of compounds having a hydrophobic group and a reactive hydrogen atom, for example, aliphatic alcohols, acids, amides or alkyl phenols with alkylene oxides, especially ethylene oxide either alone or with propylene oxide. Specific nonionic detergent compounds are C6 to C22 alkyl phenol- ethylene oxide condensates, generally 5 to 25 EO, i.e. 5 to 25 units of ethylene oxide per molecule, and the condensation products of aliphatic Cs to Cis primary or secondary linear or branched alcohols with ethylene oxide, generally 5 to 40 EO.

Suitable anionic detergent compounds which may be used can be water-soluble alkali metal salts of organic sulphates and sulphonates having alkyl radicals con- taining from about 8 to about 22 carbon atoms, the term alkyl being used to include the alkyl portion of higher acyl radicals. Examples of suitable synthetic anionic detergent compounds are sodium and potassium alkyl sulphates, especially those obtained by sulphating higher Cs to Cis alcohols, produced for example from tallow or coconut oil, sodium and potassium alkyl C9 to C20 benzene sulphonates, particularly sodium linear secondary alkyl C10 to C15 benzene sulphonates; and sodium alkyl glyceryl ether sulphates, especially those ethers of the higher alcohols derived from tallow or coconut oil and synthetic alcohols derived from petroleum. The anionic surfactant may also include soaps of C6-C22 fatty acids. The preferred anionic detergent compounds are sodium Cn to Cis alkyl benzene sulphonates and sodium C12 to Cis alkyl sulphates. Salts of sulphonates included as hydrotrobes can additionally be considered as anionic surfactants as defined herein. Also applicable are surfactants such as those described in EP-A-328 177 (Unilever), which show resistance to salting-out, the alkyl polyglycoside surfactants described in EP-A-070 074, and alkyl

monoglycosides.

The nonionic detergent is present in amounts of from 2 to 40 wt.%, preferably from 5 to 35 wt.%, more preferably from 6 to 20 wt.%. The anionic surfactant is present in amounts of from 4 to 40 wt.%, preferably from 5 to 35 wt.%, more preferably from 6 to 20 wt.%.

The total amount of surfactant present in the liquid composition is preferably at least 6 wt.%, more preferably at least 10 wt.%, more preferably the total amount of surfactant is from 15 to 65 wt.%, preferably from 10 to 50 wt.%.

Other surfactants such as amphoteric, zwitterionic and cationic surfactants may also be present in addition to the aforementioned nonionic and anionic

surfactants.

Cationic Polysaccharide Polymer

This term refers to polymers having an overall positive charge.

Preferably the cationic polysaccharide polymer is a cationic guar or cationic cellulose polymer. Most preferably the cationic polymer is a cationic cellulose polymer, for example, quaternised hydroxy ethyl cellulose.

The composition may include a single cationic polysaccharide polymer or a mixture of cationic polymers, providing that at least one of them is a cationic polysaccharide polymer. The term "cationic polysaccharide polymer" refers to polymers having a

polysaccharide backbone and an overall positive charge. Polysaccharides are polymers made up from monosaccharide monomers joined together by glycosidic bonds.

The cationic polysaccharide-based polymers present in the compositions of the invention have a modified polysaccharide backbone, modified in that additional chemical groups have been reacted with some of the free hydroxyl groups of the polysaccharide backbone to give an overall positive charge to the modified cellulosic monomer unit.

A preferred class of cationic polysaccharide polymers suitable for this invention are those that have a polysaccharide backbone modified to incorporate a quaternary ammonium salt. Preferably the quaternary ammonium salt is linked to the polysaccharide backbone by a hydroxyethyl or hydroxypropyl group.

Preferably the charged nitrogen of the quaternary ammonium salt has one or more alkyl group substituents. Preferred cationic polysaccharide-based polymers have a guar based, or cellulosic based backbone. Cellulose based cationic polymers are most preferred.

Guar is a galactomannan having a β-1 ,4 linked mannose backbone with

branchpoints to a-1 ,6 linked galactose units.

Suitable cationic guar gum derivatives, such as guar hydroxypropyltrimonium chloride, specific examples of which include the Jaguar series commercially available from Rhone-Poulenc Incorporated and the N-Hance series commercially available from Aqualon Division of Hercules, Inc. An example of a preferred guar based cationic polymer is guar 2-hydroxy-3- (trimethylammonium) propyl ether salt.

Cellulose is a polysaccharide with glucose as its monomer, specifically it is a straight chain polymer of D-glucopyranose units linked via β-1 ,4 glycosidic bonds and is a linear, non-branched polymer.

Example cationic cellulose polymers are salts of hydroxyethyl cellulose reacted with trimethyl ammonium substituted epoxide, referred to in the field under the International Nomenclature for Cosmetic Ingredients as Polyquatemium 10 and is commercially available from the Amerchol Corporation, a subsidiary of The Dow Chemical Company, marketed as the Polymer LR, JR, and KG series of polymers. Other suitable types of cationic celluloses include the polymeric quaternary ammonium salts of hydroxyethyl cellulose reacted with lauryl dimethyl ammonium- substituted epoxide referred to in the field under the International Nomenclature for Cosmetic Ingredients as Polyquatemium 24. These materials are available from Amerchol Corporation marketed as Polymer LM-200.

Typical examples of preferred cationic cellulosic polymers include

cocodimethylammonium hydroxypropyl oxyethyl cellulose,

lauryldimethylammonium hydroxypropyl oxyethyl cellulose,

stearyldimethylammonium hydroxypropyl oxyethyl cellulose, and

stearyldimethylammonium hydroxyethyl cellulose; cellulose 2-hydroxyethyl 2- hydroxy 3-(trimethyl ammonio) propyl ether salt, polyquaternium-4,

polyquaternium-10, polyquaternium-24 and polyquaternium-67 or mixtures thereof.

More preferably the cationic cellulosic polymer is a quaternised hydroxy ether cellulose cationic polymer. These are commonly known as polyquaternium-10. Suitable commercial cationic cellulosic polymer products for use according to the present invention are marketed by the Amerchol Corporation under the trade name UCARE.

The counterion of the cationic polymer is freely chosen from the halides: chloride, bromide, and iodide; or from hydroxide, phosphate, sulphate, hydrosulphate, ethyl sulphate, methyl sulphate, formate, and acetate.

Without wishing to be bound by theory, it is believed that the species responsible for providing a softening benefit in these formulations is a polymer/surfactant complex, especially a cationic polysaccharide polymer/AEC complex.

The cationic polysaccharide polymer is present at a level of from 0.1 to 1 .5 wt.%, preferably from 0.1 to 1 wt.%, more preferably from 0.2 to 1 wt.%. Many of the aforementioned cationic polymers can be synthesised in, and are commercially available in, a number of different molecular weights. Preferably the molecular weight of the cationic polymer is from 10,000 to 2,000,000 Daltons, more preferably from 10,000 to 500,000 Daltons. Optional Ingredients

The liquid detergent composition may optionally comprise one or more of the following optional ingredients, shading dye, enzyme, antiredeposition polymer, dye transfer inhibiting polymer, builder, sequestrant, sunscreen and/or soil release polymer.

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™. Another suitable builder is sodium carbonate.

If utilized, the builder materials may comprise from about 0.5% to 20 wt%, preferably from 1 wt% to 10 wt%, of the composition. The preferred builder level is less than 10 wt% and preferably less than 5 wt% of the composition.

Preferably the laundry detergent formulation is a non-phosphate built laundry detergent formulation, i.e., contains less than 1 wt.% of phosphate. Shading Dye

Shading dyes deposit to fabric during the wash or rinse step of the washing process providing a visible hue to the fabric. Shading of white garments may be done with any colour depending on consumer preference. Blue and Violet are particularly preferred shades and consequently preferred dyes or mixtures of dyes are ones that give a blue or violet shade on white fabrics. The shading dyes used are preferably blue or violet.

The shading dye chromophore is preferably selected from the group comprising: mono-azo, bis-azo, triphenylmethane, triphenodioxazine, phthalocyanin, naptholactam, azine and anthraquinone. Most preferably mono-azo, bis-azo, azine and anthraquinone.

Most preferably the dye bears at least one sulfonate group.

Preferred shading dyes are selected from direct dyes, acid dyes, hydrophobic dyes, cationic dyes and reactive dyes.

If included, the shading dye is present is present in the liquid composition in range from 0.0001 to 0.01 wt %.

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. The total amount of the fluorescent agent or agents used in the composition is generally from 0.005 to 2 wt.%, more preferably 0.01 to 0.1 wt.%. 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-sulfophenyl)-2H-napthol[1 ,2- d]trazole, 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- morpholino-1 ,3,5-triazin-2-yl)]amino} stilbene-2-2' disulfonate, and disodium 4,4'- bis(2-sulfoslyryl)biphenyl.

Perfume

Preferably the composition comprises a perfume. The perfume is preferably in the range from 0.001 to 3 wt.%, most preferably 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.

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.

It is preferred that the laundry treatment composition does not contain a peroxygen bleach, e.g., sodium percarbonate, sodium perborate, and peracid.

Polymers

The composition may comprise one or more polymers. Polymers can assist in the cleaning process by helping to retail soil in solution or suspension and/or preventing the transfer of dyes. Polymers can also assist in the soil removal process. Dye transfer, anti-redeposition and soil-release polymers are described in further detail below.

The composition may comprise one or more polymers. Examples are

carboxymethylcellulose, hydroxyethyl cellulose, hydroxpropyl cellulose, poly(ethylene glycol), polyvinyl alcohol), ethoxylated polyamines,

polycarboxylates such as polyacrylates, maleic/acrylic acid copolymers and lauryl methacrylate/acrylic acid copolymers. Dye transfer inhibitors

Modern detergent compositions typically employ polymers as so-called 'dye- transfer inhibitors'. These prevent migration of dyes, especially during long soak times. Generally, such dye-transfer inhibiting agents include polyvinyl pyrrolidone polymers, polyamine N-oxide polymers, copolymers of N-vinylpyrrolidone and N- vinylimidazole, manganese pthalocyanine, peroxidases, and mixtures thereof, and are usually present at a level of from 0.01 to 10 wt.% based on total amount in the laundry composition.

Anti-redeposition polymers

Anti-redeposition polymers are designed to suspend or disperse soil. Typically antiredeposition polymers are ethoxylated and or propoxylated polyethylene imine or polycarboxylate materials, for example, Acrylic acid based homo or copolymers available under the trade mark ACUSOL from Dow Chemical, Alcosperse from Akzonobel or Sokolan from BASF.

Soil Release Polymers

Examples of suitable soil release polymers include graft copolymers of polyvinyl ester), e.g., Ci -C6 vinyl esters, preferably polyvinyl acetate) grafted onto polyalkylene oxide backbones. Commercially available soil release agents of this kind include the SOKALAN type of material, e.g., SOKALAN HP-22, available from BASF (Germany). Further suitable soil release polymers of a different type include the commercially available material ZELCON 5126 (from DuPont) and MILEASE T (from ICI). If present, the soil release polymer may be included at a level of from from 0.01 to 10 wt.% based on total amount in the laundry

composition. Further examples of soil release polymers are terephthalic acid / glycol copolymers sold under the tradenames Texcare, Repel-o-tex, Gerol, Marloquest, Cirrasol. Hydrotrope

The liquid detergent composition may optionally include a hydrotrope, which can prevent liquid crystal formation. The addition of the hydrotrope thus aids the clarity/transparency of the composition. Suitable hydrotropes include but are not limited to propylene glycol, ethanol, urea, salts of benzene sulphonate, toluene sulphonate, xylene sulphonate or cumene sulphonate. Suitable salts include but are not limited to sodium, potassium, ammonium, monoethanolamine,

triethanolamine. Salts of sulphonates can also be considered as anionic surfactants as defined herein. Preferably, the hydrotrope is selected from the group consisting of propylene glycol, xylene sulfonate, ethanol, and urea to provide optimum performance. The amount of the hydrotrope is generally in the range of from 0 to 30%, preferably from 0.5 to 30%, more preferably from 0.5 to 30%, most preferably from 1 to 15%. Enzymes

Enzymes can also be present in the formulation. Preferred enzymes include protease, lipase, pectate lyase, amylase, cutinase, cellulase, mannanase. If present the enzymes may be stabilized with a known enzyme stabilizer for example boric acid.

Examples

Method of Production

Water, fluorescer and hydrotropes are mixed together at ambient temperature (approximately 22°C) for 2-3 minutes at a shear rate of 130 rpm using a Janke & Kunkel IKA RW20 overhead mixer. Salts and alkalis are added and mixed for 5 minutes prior to addition of surfactants and any alkyl ether carboxylic acid and/or fatty acid. The temperature of the mix rises to around 50-60°C at this point. After allowing to cool to <30C, the LR400 solution, PVP or PVP/PVI and any remaining components such as perfume, preservatives, opacifier and dyes are added. Formulations in accordance with the invention are listed in tables 1 & 2

Table 1

Ingredient I II III IV V VI

%.wt %.wt %.wt %.wt %.wt %.wt

LAS ACID 5 10 10 10 15 14

SLES 5 3 6 5

NEODOL 25-7E 10 10 16 12 5 14

MARLOWET 1072 3 6 6 3 6 3 (Alkyl Ether Carboxylate)

PRIFAC 5908 3 3

PROPYLENE GLYCOL 9 9 11 14 15 5

GLYCEROL 5 5 5 5

TRIETHANOLAMINE 2 2.25 3 2 4 6

Tl NOPAL CBS-X 0.1 0.1 0.1 0.1

Polyvinylpyrrolidone 0.35 0.35 0.35 0.35 0.3

(PVP K15)

LR400 (Cationic polymer) 0.25 0.43 0.45 0.75 0.4

Jaguar C500 0.4 (Cationic polymer)

PROXEL GXL 0.04 0.04 0.04 0.01 0.01 0.01

SODIUM CHLORIDE 0.5 0.5 0.5 0.5

ACUSOL OP31 0.05 0.05 0.05 0.05 0.05 0.05

Dye 0.001 0.005 0.001 0.001 0.001 0.001

PERFUME 1.3 1.1 1.1 1.39 1.2 1.2

SODIUM HYDROXIDE to pH to pH to pH to pH to pH to pH

7 7.5 8.5 7 8 8.5

WATER to 100 to 100 to 100 to 100 to 100 to 100 Table 2

Stability Experiment Formulations

6 liquid detergent formulations were made using the aforementioned method, and their stability measured. Comparative examples (A) & (B) include additional fatty acid at ca. 3 wt.% and 6 wt.% and demonstrate the disclosure of W010/072628 A1 which disclosed formulations that include nonionic and anionic surfactants, fatty acid and cationic polymer. Examples according to the invention (1 ) to (4) incorporate 2 different alkyl ether carboxylic acids (Emulsogen COL 080 and Marlowet 1072) at 2 different inclusion levels (3.3 and 6.6 wt.%). The ingredients of the model liquid are shown in table 3: Table 3

¹ Prifac 5908 is hydrogenated topped palm kernel fatty acid available from Croda

² Emulsogen COL 080 is Oleic alcohol polyethylene glycol ether (8EO) carboxylic acid available from Clariant

³ Marlowet 1072 is C12-C14 alcohol polyethylene glycol ether (~ 5EO) carboxylic acid available from Sasol

⁴ LR400 is a cationic hydroxyether cellulose polymer (known as polyquaternium 10) available from Dow Chemical

Stability Experiment

The comparative examples A, & B and examples 1 -4 according to the invention were formulated to 3 different pH levels (pH 7, pH 7.5 and pH 8). The samples made at these various pH levels were stored overnight at 5°C. The formulation was deemed unstable if it had turned opaque, or if it has a significant haze that could not be seen through. The formulation was deemed stable if it was still clear. The results are shown in table 4: Table 4

As is clear from the experimental data, formulations comprising alkyl ether carboxylic acids had a superior stability at low pH (pH 7 to 8.5) in comparison to the prior art formulations from WO10/072628 A1 which just included fatty acid.

Claims

1 . A laundry liquid detergent composition comprising:-

(a) from 2 to 40 wt.% nonionic surfactant, comprising an alcohol

ethoxylate;

(b) from 4 to 40 wt.% anionic surfactant;

(c) from 1 to 12 wt.% alkyl ether carboxylic acid or carboxylate salt

thereof; and,

(d) from 0.1 to 1 .5 wt.% cationic polysaccharide polymer.

2. A composition according to claim 1 , having a pH of from 6.2 to 9, preferably from pH 6.5 to 8.5, most preferably from pH 6.5 to 8.

A composition according to claim 1 or claim 2, wherein the alkyl ether carboxylic acid or carboxylate salt thereof is present at a level of from 1 to

10 wt.%, preferably at a level of from 2 to 7.5 wt.%.

4. A composition according to any preceding claim, wherein the alkyl ether carboxylic acid or carboxylate salt is depicted by:

wherein R denotes a saturated or unsaturated C6-C22 alkyl chain; R¹ and R² are either both hydrogen; or R¹ is hydrogen and R² is CH₃; or R¹ is CH₃ and R² is hydrogen; R³ is hydrogen, or a solubilising cation such as sodium, potassium, ammonium or substituted ammonium; and, n is a number from 2 to 20, preferably 3 to 12, denoting the number of repeat units.

5. A composition according to any preceding claim, wherein the alkyl ether carboxylic acid or carboxylate salt has a Cs-Cis alkyl chain with between 2- 12 glycol repeat units, wherein the glycol repeat units are selected from ethylene glycol, propylene glycol or mixtures thereof.

6. A composition according to any preceding claim, wherein the cationic

polysaccharide polymer is present at a level of from 0.1 to 1 wt.%.

7. A composition according to any preceding claim, wherein the cationic

polysaccharide polymer is a cationic cellulose polymer.

8. A composition according to any preceding claim, wherein the cationic

polysaccharide polymer is a cationic guar polymer.

9. A composition according to claim 7, wherein the cationic cellulose polymer is quaternised hydroxy ethyl cellulose.

10. A composition according to any preceding claim, wherein the composition further comprises a betaine surfactant.

1 1 . A composition according to any preceding claim, wherein the composition further comprises an ingredient selected from, shading dye, enzyme, an antiredeposition polymer, a dye transfer inhibiting polymer, builder, sequestrant, sunscreen and/or soil release polymer.