TECHNICAL FIELD

This invention relates to a liquid detergent composition comprising anionic surfactant, lipase enzyme and a bleach catalyst and to the use of the composition for the removal of curcuminoid stains from surfaces, for example from fabrics.

BACKGROUND

WO09153184 suggests that an improved laundry detergent liquid concentrate may be obtained by replacing surfactant with a mixture of more weight efficient ingredients selected from polymers and enzymes. A preferred composition uses lipase enzyme in combination with EPEI and a polyester soil release polymers to achieve excellent oily soil and particulate detergency at significantly lower in-wash surfactant levels than would normally be delivered from such a high performance laundry liquid. In the description it is further taught that a bleach catalyst may be included. A long list of such catalysts is given. The non-bridged air bleaching catalyst preferred in WO2002/048307 (Unilever) is specifically mentioned as being preferred for use in WO09153184.

Air bleaching catalysts as described and claimed in WO2002/048301 (Unilever) are referenced on page 48 lines 1 -2 of WO09153184 where it says "suitable bispidon catalyst materials and their action are described in WO02/48301 ". The combination of a specific amount of the selected air bleaching catalyst with a specific amount of lipase is not exemplified in WO09153184. WO 2002/48301 (Unilever) disclosed a group of bridged ligand air bleaching catalysts that included N2Py3o on page 30. There is no disclosure of this catalyst in combination with lipase, nor any suggestion that the combination would have synergistic effects on the air bleaching of curcuminoid (yellow and green curry) stains.

In addition to WO2002/048301 there are other documents that disclose detergent compositions comprising the bridged ligand catalyst N2Py3o. None of them discloses a liquid detergent composition comprising anionic surfactant with at least 1 wt% (1000LU/g) Lipase in combination with the bleach catalyst of

WO2002/048301 or the use of such a composition for air bleaching of curcuminoid stains.

Among these other documents are EP 1369472 (Unilever); WO 2010/006861 (Unilever), WO 2006/133773 (Unilever) which teaches that Lipex is a preferred lipase for use in conjunction with the catalyst system. WO 2005/059075

(Unilever) that discloses a protease with the catalyst in its examples. In

WO01 /00768, Lipases are said to be preferred enzymes. WO 2005/033256 (Unilever). WO 2004/1 1 1 173 (Unilever) that discloses liquids containing the bleach catalyst of interest but fails to disclose the amount or type of enzyme in its liquid detergent example.

WO 2004/1 1 1 174 (Unilever) discloses the use of anti-oxidant to protect the catalyst in liquids during storage. A commercial liquid formulation containing an unspecified amount of Lipex into which appropriate levels of an unspecified catalyst, antioxidant and perfume is disclosed (p19). The example showing improved perfume stability uses a bridged bleach catalyst of the correct type, but no lipase is present. WO 2002/50229 (Unilever) that discloses to air bleach with a combination of metal catalyst and an air bleaching facilitator (unsaturated soap). The presently claimed catalyst is not exemplified or used with lipase. US2003/166485 (Unilever) discloses a combination of a lipase, lipogenase and bleach catalyst used in air bleaching mode. The examples show the effect with a non- bridged ligand type of catalyst (MeN4Py)FeCI CI. The examples without any lipogenase show some benefit of the combination of a lipase with this non bridged bleach catalyst compared to use of the lipase alone or the catalyst alone.

Paragraphs 26 to 41 of the disclosure suggest that a bridged type of catalyst may be used as an alternative to the non-bridged one exemplified. There is no disclosure of any specific bridged catalysts and in particular there is no disclosure of ([Fe(N2py3o)CI]CI).

SUMMARY OF THE INVENTION

According to a first aspect of the present invention there is provided a detergent liquid comprising:

a) from 20 to 70 wt% surfactant, comprising at least 5 wt% (based on total liquid composition) anionic surfactant,

b) at least 1000 LU per g of liquid of lipase,

b) 0.05 to 0.3 wt% of a transition metal catalyst, the catalyst being a ligand of the formula (I) complexed with a transition metal, selected from Fe(ll) and Fe(lll),

Rl

( I ) Where R1 and R2 are independently selected from:

C1 -C4-alkyl,

C6-C10-aryl, and,

a group containing a heteroatom capable of coordinating to a transition metal, wherein at least one of R1 and R2 is the group containing the heteroatom;

preferably at least one of R1 or R2 is pyridin-2-ylmethyl. More preferably the catalyst is one in which R1 is pyridin-2-yl methyl. Most preferably R1 is pyridin-2- ylmethyl and R2 is methyl; R3 and R4 are independently selected from hydrogen, C1 -C8 alkyl, C1 -C8- alkylene-0-C1 -C8-alkyl, C1 -C8-alkylene-O-C6-C10-aryl, C6-C10-aryl, C1 -C8- hydroxyalkyl, and -(CH2)nC(0)OR5; wherein R5 is independently selected from: hydrogen, C1 -C4-alkyl, n is from 0 to 4, and mixtures thereof; preferably R3=R4= -C(0)OMe and, each R is independently selected from: hydrogen, F, CI, Br, hydroxyl, C1 -C4- alkylO-, -NH-CO-H, -NH-CO-C1 -C4-alkyl, -NH2, -NH-C1 -C4-alkyl, and C1 -C4- alkyl; preferably each R is hydrogen,

X is selected from C=0, -[C(R6)2]y- wherein Y is from 0 to 3, preferably 1 , each R6 is independently selected from hydrogen, hydroxyl, C1 -C4-alkoxy and C1 -C4- alkyl preferably X is C=0. Most preferably the catalyst is ([Fe(N2py3o)CI]CI) with structure (II):

Also known as lron(1 +), chloro[rel-1 ,5-dimethyl (1 R,2S,4R,5S)-9,9-dihydroxy-3- methyl-2,4-di(2-pyridinyl- ^« N)-7-[(2-pyridinyl- ^» N)methyl]-3,7- diazabicyclo[3.3.1 ]nonane-1 ,5-dicarboxylate-' N3,' N7]-, chloride (1 :1 ), (OC-6-63)- [CAS Registry Number 478945-46-9].

Advantageously, the composition further comprises ethoxylated polyethyleneimine (EPEI). Most advantageously it further comprises a polyester soil release polymer (SRP).

For enhanced stability of the soil release polymer and the bleach catalyst it is desirable that the in-bottle pH of the composition is acidic and lies in the range 6 to less than 7, preferably 6.1 to 6.9 and more preferably 6.3 to 6.7. For even greater stability the bleach catalyst may be encapsulated.

The composition preferably comprises at least two further enzymes selected from protease, mannanase, amylase, cellulase and pectate lyase. Most preferably the composition comprises protease. The composition may be a laundry detergent. In which case, the anionic surfactant preferably comprises linear alkyl benzene sulphonate.

The composition surfactant system may further comprise one or more of ethoxylated nonionic surfactant, amphoteric surfactant and ethoxylated anionic surfactant. The amphoteric surfactant may be selected from carbobetaine and amine oxide and mixtures thereof.

The composition may be aqueous with a water content of greater than 20 wt%. Alternatively it may be non aqueous with a water content of less than 15 wt%, preferably less than 10 wt%. Such a non aqueous composition may conveniently be contained in a water soluble sachet that can be added to water by a consumer. The sachet is desirably made from a conventional water soluble film, for example a poly vinyl alcohol as is known in the art.

Also according to a second aspect of the present invention there is provided a method of air bleaching a surface on which there is a curcuminoid stain, the method comprising treating the surface with a composition according to the invention any preceding claim and then exposing the surface to atmospheric air, preferably the exposure to air has a duration of at least 1 hour.

Because it is a liquid, the composition may be applied to the surface in undiluted, from the bottle, form. Consumers prefer many types of cleaning composition to be offered as a liquid, hard surface cleaners and fabric washing liquids being leading examples.

Alternatively, the method may be performed by taking an aliquot of the

composition and diluting it by at least 600 times its own weight of water to form a wash liquor and then contacting the surface with the wash liquor so formed. Preferably the surface is cloth fabric and most preferably it is cotton. The method involving dilution may take place in a front loading automatic washing machine. According to a third aspect there is provided use of a combination of the catalyst as defined in claim 3 and lipase to air bleach a curcuminoid stain.

The preferred catalyst used in this invention is given a shorthand code of

[Fe(N2py3o)CI]CI - see WO02248301 . The structure (II) for it is:

lron(1 +), chloro[rel-1 ,5-dimethyl (1 R,2S _! 4R _! 5S)-9 _! 9-dihydroxy-3-methyl-2,4-di(2- pyridinyl-' N)-7-[(2-pyridinyl-' N)methyl]-3,7-diazabicyclo[3.3.1 ]nonane-1 ,5- dicarboxylate-' N3,' N7]-, chloride (1 :1 ), (OC-6-63)- [CAS Registry Number 478945-46-9]. DETAILED DESCRIPTION OF THE INVENTION

It has been found that a particular type of air bleaching catalyst as described in WO02/48301 has a surprisingly strong synergistic effect with lipase in terms of the visual removal of yellow curry (curcuminoid) stains when a washed stain is dried in contact with a liquid comprising the catalyst and the lipase (air bleaching effect). The effect is particularly strong when high levels of the catalyst (and lipase) and low levels of surfactant are used. This may be due to the higher efficacy of the lipase when anionic surfactant is reduced. The lipase catalyst synergy is therefore particularly suited to the low surfactant compositions of the type described in WO091 53184. Lipase enzyme

The amount of lipase should be at least 1 wt% to obtain the synergistic effect. 1 wt% is equivalent to 1000 LU per gram of the detergent composition. Preferably the lipase is 2000-20,000 LU per gram of the detergent composition. Suitable lipase enzyme is obtainable from Humicola lanuginosa, Pseudomonas

pseudoalcaligenes, or Rhizomucor miehei. Preferred lipase enzymes include those of bacterial or fungal origin. Chemically modified or protein engineered mutants are included. Most preferred lipases are obtainable from Humicola lanuginose. The detergent compositions preferably comprise 2500-4,000 LU per gram of the detergent composition, of lipase enzyme. In this specification LU or lipase units are defined as they are in EP-A-258 068 (Novo Nordisk). A further method of assessing the enzymatic activity is by measuring the reflectance at 460 nm according to standard techniques. Examples of useful lipases include lipases from Humicola which comprise a polypeptide having an amino acid sequence which has at least 90% sequence identity with the wild-type lipase derived from Humicola lanuginose, most preferably strain DSM 4109. The amount in the composition is higher than typically found in liquid detergents. This can be seen by the ratio of non-soap surfactant to lipase enzyme, in particular. A particularly preferred lipase enzyme is available under the trademark Lipoclean™ from Novozymes.

Examples of lipases are lipases from Humicola (synonym Thermomyces), e.g. from H. lanuginosa ( Γ. 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 Sac/V/us lipase, e.g. from B. subtilis (Dartois et al. (1993), Biochemica et Biophysica Acta, 1 131 , 253-360), B. stearothermophilus (JP 64/744992) or B. pumilus (WO

91 /16422). The preferred lipases have a high degree of homology with the wild- type lipase derived from Humicola lanuginose.

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.

Preferred commercially available lipase enzymes include Lipolase™ and Lipolase Ultra™, Lipex™ and Lipoclean™ (Novozymes A/S).

In addition to lipase one or more other enzymes may be present.

Advantageously, the presence of relatively high levels of calcium in the

compositions of the invention has a beneficial effect on the turnover of certain enzymes, particularly lipase enzymes and preferably lipases from Humicola.

Suitable enzymes for the compositions of the invention can be found in the enzyme classes of the esterases and lipases, (EC 3.1 .1 . ^* , wherein the asterisk denotes any number). Cutinases differ from classical lipases in that they do not possess a helical lid covering the catalytic binding site. Cutinases belong to a different subclass of enzymes (EC 3.1 .1 .50) and are regarded to be outside the scope of the present invention. The enzyme to be used in the detergent compositions according to the invention can be produced by cloning the gene for the enzyme into a suitable production organism, such as Bacilli, or Pseudomonaceae, yeasts, such as Saccharomyces, Kluyveromyces, Hansenula or Pichia, or fungi like Aspergillus. The preferred production organism is Aspergillus with especial preference for Aspergillus oryzae.

The lipase enzyme can be stabilised for use in a liquid detergent by various techniques as for example disclosed in US-A-4 261 868 and US-A-4 318 818.

Bleach catalyst

The selected bleach catalyst is a cross-bridged polydentate N-donor ligand capable of forming a complex with a transition metal, wherein said complex is capable of catalysing the bleaching of stains on fabrics by means of atmospheric oxygen. The bleach catalyst is a very specific complex of Iron and a multicyclic organic ligand as described already in W021002/48301 . The preferred material is [Fe(N2py3o)CI]CI - see WO02248301 . Its structure (II) is:

( I D lron(1 +), chloro[rel-1 ,5-dimethyl (1 R,2S _! 4R,5S)-9,9-dihydroxy-3-methyl-2,4-di(2- pyridinyl-' N)-7-[(2-pyridinyl-' N)methyl]-3,7-diazabicyclo[3.3.1 ]nonane-1 ,5- dicarboxylate-' N3,' N7]-, chloride (1 :1 ), (OC-6-63)- [CAS Registry Number 478945-46-9]

It is known that the bridged ligand catalysts are more stable under acidic conditions and the detergent liquids are therefore preferably acidic. Such liquids are compatible with SRPs that suffer from hydrolysis when included in alkaline liquids (especially if TEA is present). Texcare SRN170 has been found to be susceptible to alkaline hydrolysis in laundry liquids.

Anti oxidant

It is highly desirable that an antioxidant is added to the composition to preserve the catalyst activity. The composition preferably comprises from 0.005 to 2 wt% of anti-oxidant. More preferably, the anti-oxidant is present at a concentration in the range of 0.01 to 0.08 wt%.

Anti-oxidants are substances as described in Kirk-Othmer (Vol 3, pg 424) and in Uhlmans Encyclopaedia (Vol 3, pg 91 ).

One class of anti-oxidants used in the present invention is alkylated phenols.

Especially, hindered phenolic compounds of alkylated phenols according to this formula. A particularly preferred hindered phenolic compound of this type is 2,6-di- tert-butyl-hydroxy- toluene (BHT).

Furthermore, the antioxidant used in the composition of the invention may be selected from the group consisting of a-, y-, 8-tocopherol, ethoxyquin, 2,2,4- trimethyl-1 ,2- dihydroquinoline, 2,6-di-tert-butyl hydroquinone, tert-butyl- hydroxy anisole, lignosulphonic acid and salts thereof, and mixtures thereof. Ethoxyquin (1 ,2-dihydro-6- ethoxy-2,2,4-trimethylchinolin) is marketed under the name

Raluquin™ by the company Rashig.

Other types of antioxidant that may be used in the present invention are 6 hydroxy-2, 5, 7, 8-tetra-methylchroman-2-carboxylic acid (Trolox™) and 1 , 2- benzisothiazoline-3-one (Proxel GXL).

A further class of anti-oxidants which may be suitable for use in the present invention is a benzofuran or benzopyran derivative. Anti-oxidants such as tocopherol sorbate, butylated hydroxy benzoic acids and their salts, gallic acid and its alkyl esters, uric acid and its salts and alkyl esters, sorbic acid and its salts, and dihydroxy fumaric acid and its salts may also be used..

The preferred types of anti-oxidants for use in the present invention are 2,6-di-tert- butyl-hydroxy-toluene (BHT), · ,· ,· ,· ^tocopherol and mixtures thereof, 6-hydroxy- 2, 5, 7, 8-tetra-methylchroman-2- carboxylic acid (Trolox™), 1 , 2- benzisothiazoline-3-one (Proxel GXL) and mixtures thereof. The most preferred anti-oxidants are 2,6-di-tert-butyl-hydroxy-toluene (BHT, 1 , 2 benzisothiazoline-3- one (Proxel GXL TM) and mixtures thereof.

Surfactants

Surfactants assist in removing soil from the textile materials and also assist in maintaining removed soil in solution or suspension in the wash liquor. Blends of anionic and nonionic surfactants are a preferred feature of the present invention. The amount of anionic surfactant is at least 5 wt% and preferably at least 10 wt%. Preferably, anionic surfactant forms the majority of the surfactant (a). Anionic

Preferred anionic surfactants are alkylbenzene sulphonates, particularly linear alkylbenzene sulphonates having an alkyi chain length of C ₈ -C-| ₅ . The counter ion for anionic surfactants is generally an alkali metal, typically sodium, although other counter-ions such as MEA, TEA or ammonium can be used.

Preferred linear alkyi benzene sulphonate surfactants are Detal LAS with an alkyi chain length of from 8 to 15, more preferably 12 to 14.

It is further desirable that the composition comprises an alkyi polyethoxylate sulphate anionic surfactant of the formula (I):

RO(C ₂ H ₄ 0) _x S0 ₃ ^" M ⁺ (I)

where R is an alkyi chain having from 10 to 22 carbon atoms, saturated or unsaturated, M is a cation which makes the compound water-soluble, especially an alkali metal, ammonium or substituted ammonium cation, and x averages from 1 to 15. Preferably R is an alkyi chain having from 12 to 16 carbon atoms, M is Sodium and x averages from 1 to 3, preferably x is 3; This is the anionic surfactant sodium lauryl ether sulphate (SLES). It is the sodium salt of lauryl ether sulphonic acid in which the predominantly C12 lauryl alkyi group has been ethoxylated with an average of 3 moles of ethylene oxide per mole.

Nonionic

Nonionic surfactants include primary and secondary alcohol ethoxylates, especially C ₈ -C ₂ o aliphatic alcohol ethoxylated with an average of from 1 to 20 moles of ethylene oxide per mole of alcohol, and more especially the C-| ₀ -C-| ₅ primary and secondary aliphatic alcohols ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of alcohol. Non-ethoxylated nonionic surfactants include alkyl polyglycosides, glycerol monoethers and polyhydroxy amides (glucamide). Mixtures of nonionic surfactant may be used. When included therein the composition contains from 0.2 wt% to 40 wt%, preferably 1 wt% to 20 wt%, more preferably 5 to 15 wt% of a non-ionic surfactant, such as alcohol ethoxylate, nonylphenol ethoxylate, alkylpolyglycoside, alkyldimethylamineoxide, ethoxylated fatty acid monoethanolamide, fatty acid monoethanolamide, polyhydroxy alkyl fatty acid amide, or N-acyl N-alkyl derivatives of glucosamine ("glucamides").

Nonionic surfactants that may be used include the primary and secondary alcohol ethoxylates, especially the C-8-C20 aliphatic alcohols ethoxylated with an average of from 1 to 35 moles of ethylene oxide per mole of alcohol, and more especially the C-10-C-15 primary and secondary aliphatic alcohols ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of alcohol.

Amine Oxide and carbobetaine The composition may comprise up to 10 wt% of a carbobetaine or an amine oxide or mixtures thereof. The amine oxide has the formula:

R ¹ N(O)(CH ₂ R ² ) ₂

In which R ¹ is a long chain moiety each CH ₂ R ² are short chain moieties. R ² is preferably selected from hydrogen, methyl and -CH ₂ OH. In general R ¹ is a primary or branched hydrocarbyl moiety which can be saturated or unsaturated, preferably, R ¹ is a primary alkyl moiety. R ¹ is a hydrocarbyl moiety having chain length of from about 8 to about 18. Preferred amine oxides have R ¹ is C ₈ -Ci ₈ alkyl, and R ² is H. These amine oxides are illustrated by C12-14 alkyldimethyl amine oxide, hexadecyl dimethylamine oxide, octadecylamine oxide.

A preferred amine oxide material is Lauryl dimethylamine oxide, also known as dodecyldimethylamine oxide or DDAO. Such an amine oxide material is commercially available from Huntsman under the trade name Empigen® OB. Amine oxides suitable for use herein are also available from Akzo Chemie and Ethyl Corp. See McCutcheon's compilation and Kirk-Othmer review article for alternate amine oxide manufacturers.

Whereas in certain of the preferred embodiments R ² is H, it is possible to have R ² slightly larger than H. Specifically, R ² may be CH ₂ OH, such as: hexadecylbis(2- hydroxyethyl)amine oxide, tallowbis(2-hydroxyethyl)amine oxide, stearylbis(2- hydroxyethyl)amine oxide and oleylbis(2- hydroxyethyl)amine oxide.

Preferred amine oxides have the formula:

O ^" - N ⁺ (Me) ₂ R ¹ (3) where R ¹ is C12-16 alkyl, preferably C12-14 alkyl; Me is a methyl group.

A preferred zwitterionic carbobetaine material is available from Huntsman under the name Empigen® BB. Betaines, improve particulate soil detergency in the compositions of the invention. Additional surfactants

Other surfactants than the preferred LAS, SLES, nonionic and amine oxide/ carbobetaine may be added to the mixture of detersive surfactants. However cationic surfactants are preferably substantially absent.

Although less preferred, some alkyl sulphate surfactant (PAS) may be used, especially the non-ethoxylated C12-15 primary and secondary alkyl sulphates. A particularly preferred material, commercially available from Cognis, is Sulphopon 1214G.

Further Components

In addition to the essential surfactant, lipase and bleach catalyst, further optional components of the compositions are as described in WO09153184. Of particular note are the high levels of polymers that form a preferred component of the low in wash surfactant compositions preferred for use in the present invention. EPEI and polyester soil release polymer are most preferred components of the detergent liquids and are advantageously used in combination and at high levels.

EPEI

A particularly preferred class of polymer for use in the present invention is polyethylene imine, preferably modified polyethylene imine. Polyethylene imines are materials composed of ethylene imine units -CH2CH2NH- and, where branched, the hydrogen on the nitrogen is replaced by another chain of ethylene imine units. These polyethyleneimines can be prepared, for example, by polymerizing ethyleneimine in the presence of a catalyst such as carbon dioxide, sodium bisulphite, sulphuric acid, hydrogen peroxide, hydrochloric acid, acetic acid, and the like. Specific methods for preparing these polyamine backbones are disclosed in U.S. Pat. No. 2,182,306, Ulrich et al., issued Dec. 5, 1939; U.S. Pat. No. 3,033,746, Mayle et al., issued May 8, 1962; U.S. Pat. No. 2,208,095, Esselmann et al., issued Jul. 16, 1940; U.S. Pat. No. 2,806,839, Crowther, issued Sep. 17, 1957; and U.S. Pat. No. 2,553,696, Wilson, issued May 21 , 1951 .

Preferably, the EPEI comprises a polyethyleneimine backbone of about 300 to about 10000 weight average molecular weight; wherein the modification of the polyethyleneimine backbone is intended to leave the polymer without

quaternisation. Such nonionic EPEI may be represented as PEI(X)YEO where X represents the molecular weight of the unmodified PEI and Y represents the average moles of ethoxylation per nitrogen atom in the polyethyleneimine backbone. The ethoxylation may range from 9 to 40 ethoxy moieties per modification, preferably it is in the range of 16 to 26, most preferably 18 to 22. The polyethyleneimine polymer is present in the composition preferably at a level of between 0.01 and 25 wt%, but more preferably at a level of at least 2 wt% and/or less than 9.5 wt%, most preferably from 3 to 9 wt% and with a ratio of non- soap surfactant to EPEI of from 2:1 to 7:1 , preferably from 3:1 to 6:1 , or even to 5:1 .

Polyester soil release polymer (SRP)

In addition to EPEI, a soil release polymer, preferably of the PET POET type, may be used. Acidic compositions according to the invention are particularly suited to the types of soil release polymers disclosed in WO09153184 since they tend to decompose when stored under alkaline conditions. Alternatively an alkaline stable type of polyester soil release polymer may be used. Other polymer types

Dye transfer inhibition polymers, anti redeposition polymers and cotton soil release polymers, especially those based on modified cellulosic materials may also be used in the compositions of the present invention.

The Detergent liquids preferably do not contain any additional conventional bleach system. For example peroxy bleach compounds, for example, inorganic persalts or organic peroxyacids, capable of yielding hydrogen peroxide in aqueous solution are absent.

The composition may comprise other ingredients as set forth in WO09153184.

The invention will now be further described with reference to the following non- limiting examples.

EXAMPLES

In the examples the following materials are used:

LAS acid is C12-14 linear alkylbenzene sulphonic acid.

Fatty acid is saturated lauric fatty acid Prifac® 5908 ex Croda. SLES 3EO is sodium lauryl ether sulphate with 3 moles EO.

Empigen® BB is an alkyl betaine ex Huntsman (Coco dimethyl

carbobetaine), an amphoteric surfactant.

Nl 7EO is C12-15 alcohol ethoxylate 7EO nonionic

Neodol® 25-7 (ex Shell Chemicals).

MPG is mono propylene glycol.

TEA is triethanolamine. NaOH is 47% sodium hydroxide solution.

EPEI is Sokalan HP20 - ethoxylated polyethylene imine cleaning polymer: PEI(600) 20EO ex BASF.

SRP is polyester soil release polymer (Texcare SRN170 ex

Clariant).

Perfume is free oil perfume.

Demin water is demineralised water

Fluorescer is Tinopal 5BMGX ex Ciba

Protease enzyme is Relase Ultra 16 LEX ex Novozymes A/S

Amylase enzyme is Stainzyme 12L ¹ ex Novozymes A/S

Mannanase enzyme is Mannaway 4L ¹ ex Novozymes A/S

Patent Blue V85 is a Colorant

Acid Yellow 23 is a Colorant

Bridged catalyst is BL1749 which has lUPAC name: lron(2+),

Chloro(dimethyl 9,9-dihydroxy-3-methyl-2,4-di-(2- pyridyl) -7-(pyridin-2-ylmethyl)-3,7-diaza- bicyclo[3.3.1 ]nonane-1 ,5-dicarboxylate)-chloride. We used catalyst in the form of a granule. Level was equivalent to 0.07% neat catalyst, i.e. 0.875% granules containing 8% catalyst. Such a catalyst is available from Raghu catalytics as FeONIX-C1 .

Lipase enzyme is 100L Lipoclean from Novozymes A/S.

Supplied as a single ingredient by Novozymes AS

Example 1 - Synergistic effect of lipase and bleach catalyst on yellow curry stains

Prototype fabric washing liquids were prepared according to the compositions given in table 1 . Knitted cotton fabric swatches stained with yellow curry supplied by Warwick Equest Ltd. - where the stain is applied to washed but otherwise untreated cotton - were washed at 25 °C for 30 minutes with unstained polyester and cotton ballast such that the liquor/cloth ratio was 25/1 , using 1 .3g fabric washing liquid with composition as shown in Table 1 in one litre of 26°FH (26 degrees French Hardness according to the Internationally recognised hardness scale where 1 degree French is defined as 10 milligrams of calcium carbonate per litre of water, equivalent to 10 ppm). After removing the swatches from the wash liquor, they were rinsed twice in water at 25 °C, each rinse being of thirty seconds duration. After the second rinse the swatches were removed from the rinse and wrung out by hand, to remove excess water before being laid flat and allowed to air dry for two days.

• E values were measured before washing, and after washing and drying for the two days, using a Hunterlab XE reflectance spectrophotometer. · E is measured relative to a clean unstained piece of cotton (of the same type as used for making the stains). The difference between the before wash and after drying values of · E is recorded as · (· E), such that higher numbers denote better cleaning.

Table 1 - Concentrated Liquid Compositions

From Table 2 it can be clearly seen that although the lipase appears to have little effect on its own in Comparative Composition B and the bleach catalyst has virtually no effect on its own in Comparative composition C when they are combined in Composition 1 then the Lipase works synergistically with the bleach catalyst to improve the stain removal by air bleaching significantly compared to that obtained from use of the bleach catalyst alone (Composition C). Table 2

Example 2 - Comparison with non bridged ligand used in US2003/166485

In this comparative test the bridged catalyst BL1749 (which has lUPAC name: lron(2+), Chloro(dimethyl 9,9-dihydroxy-3-methyl-2,4-di-(2-pyridyl) -7-(pyridin-2- ylmethyl)-3,7-diaza-bicyclo[3.3.1 ]nonane-1 ,5-dicarboxylate)-chloride) as used in example 1 and with structure (II) and ligand shorthand nomenclature N2py3o was compared directly with the non-bridged catalyst with ligand MeN4py as used in US 2003/166484 and having structure (III):

The molecular weight of the bridged ligand catalyst with structure (II) according to the invention is 641 .85 and the molecular weight of the catalyst of structure (III) is 507.85. It would be expected that the prior art catalyst of structure (III) would be more effective on an equal weight basis if it was an alternative as suggested by US2003/166485. Testing was done using the concentrated liquid composition given in Table 3. The lipase used was Lipex 100L ex Novozymes and it was added over the side to each tergo pot, including the zero catalyst control

(equivalent to 1 .75% Lipex in product) The catalysts of structure (II) or structure (III) were added as indicated.

The test protocol was otherwise the same as for example 1 except that the test cloths were knitted cotton fabric swatches stained with Rogan Josh supplied by Warwick Equest Ltd. - where the stain is applied to washed but otherwise untreated cotton. The Rogan Josh used contained turmeric as one of the spices. Curcumin is a component of turmeric and is responsible for its yellow colour.

Table 3

Dequest 2010 is HEDP (1 -Hydroxyethylidene -1 ,1 ,-diphosphonic acid) ex Dequest AG.

Empigen OB is Amine Oxide ex Huntsman. Endocellulase is Endolase® 5000L, an endocellulase enzyme promoted for its whitening benefits ex Novozymes.

The stain removal data (expressed as · (· E)) for each catalyst at different levels of inclusion is given in Table 4. The catalyst according to the invention provides superior air bleaching with lipase compared to the one in the prior art.

Table 4

Example 3

The comparative testing done in Example 2 was also carried out using Lipoclean as the Lipase enzyme, as was used for Example 1 . Again, the catalyst according to the invention outperformed that of the prior art when used with the lipase to air bleach yellow curry stains.