FIELD OF INVENTION

The present invention relates to the delivery of dyes to fabrics .

BACKGROUND OF THE INVENTION

WO2005/003274, to Unilever, discloses that shading dyes may be included in detergent formulations to enhance the whiteness of garments.

WO2006/055787, to Proctor and Gamble, describes reactive dyes attached to cellulose ether in laundry formulations. The functional reactive group of the dye reacts with OH, SH or NH ₂ groups of the polymer by an addition or substitution reaction producing a covalent bond. The polymer must contain these groups for reaction to occur. The reactive dyes used are negatively charged. The shading benefit is found predominately on cellulosic garments

WO2006/055843, WO2007/087252, WO2008/091524 and WO2008/100445 (all Milliken) describe dyes linked to polyether groups via an amine group pendant to an aromatic ring, for use in laundry formulations. The shading benefit is found predominately on cellulosic garments.

WO2008/009579 (Ciba) discloses polymer chains with pendant cationic charged dyes for use in hair dyeing. US 3926830 discloses dye indicators that are linked to polymers; dye indicators are charged. Use of the polymeric dye indicators are for colouring water.

EP 0128619 discloses use of insoluble styrene dye polymers.

WO 2005/068598 discloses Liquitint Violet CT for use in laundry. Liquitint Violet CT is only disclosed in WO 2005/068598 as a polymeric colourent and, from the examples, capable of shading cotton.

It would be desirable to have a polymer dye that deposit to both cotton and polyester fabrics, found in domestic wash loads .

SUMMARY OF THE INVENTION

The dye-polymers of the present invention deposit to both cotton and polyester fabrics.

In one aspect the present invention provides a detergent composition comprising from 2 to 70 wt % of a surfactant together with from 0.0001 to 10 wt%, preferably 0.01 to 1 wt %, of a dye-polymer of molecular weight of at least 500, wherein the dye-polymer is obtainable by polymerisation of:

(a) a dye monomer, the dye monomer is an uncharged alkene covalently bound to a dye, the dye monomer having a molar extinction coefficient at a wavelength in the range 400 to 700nm of at least 1000 mol ^"1 L cm ^"1 , preferably greater than 4000 mol ^"1 L cm ^"1 , and (b) one or more further alkene comonomer (s) , the alkene monomer (s) having molar extinction coefficient at a wavelength in the range 400 to 700nm that is less than 100 mol ^"1 L cm ^"1 , preferably less than 10 mol ^"1 L cm ^"1 .

The dye-polymer is preferably obtained (formed) by polymerisation of integers (a) and (b) as detailed above.

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

(i) treating a textile with an aqueous solution of the dye-polymer, the aqueous solution comprising from 10 ppb to 100 ppm of the dye-polymer; and, from 0.0 g/L to 3 g/L, preferably 0.3 to 2 g/L, of a surfactant; (ii) optionally rinsing; and, (iii) drying the textile.

The detergent composition as described herein is most preferably a granular detergent composition.

DYE MONOMER

The dye monomer is an organic molecule which when dissolved in an organic solvent has a molar absorption extinction coefficient of 1000 mol ^"1 L cm ^"1 , preferably greater than 4000 mol ^"1 L cm ^"1 at a wavelength in the range 400-700nm, preferably 500-650nm, most preferably 540-600nm. -A-

Molar absorption coefficients are preferably measured in an organic solvent, preferably propan-2-ol, using a 1, 5 or 10cm cell.

The dye monomer is uncharged in aqueous solution at a pH in the range from 7 to 11. The dye monomer is devoid of polar solubilizing groups. In particular the dye monomer does not contain any sulphonic acid (Sθ3 ^~ ) , carboxylic acid (Cθ2 ^~ ) , or quaternary ammonium groups .

The dye is preferably selected from organic dyes selected from the following chromophore classes: anthraquinone, azo and methine, most preferably anthraquinone and mono-azo. Dyes are described in Industrial Dyes (K. Hunger ed, Wiley VCH 2003, ISBN 3-527-30426-6) .

Preferably, the dye monomer is of the form:

H ₂ C=( _^

Y—Dye _, wherein Y is an organic bridging group covalently connecting a dye to the alkene moiety of the dye monomer and Ri is selected from: H; alkyl; aryl; halogen; ester; acid amide; and, CN.

When Ri is a phenyl or benzyl group, the aromatic is not substituted by OH.

Preferably, the most direct connection (Y) of an aromatic group of the dye to the alkene carbon carrying Ri is spaced by 1 to 8 atoms, most preferably 3 to 6; the atoms are preferably selected from: C; N; 0; and, S. The alkene may also be directly connected to the dye and in this case Y is absent .

Preferably, the organic bridging group (Y) is selected from: -CONR ₄ -, -NR ₄ CO-, -COOR ₄ -, -NR ₄ -, -0-, -S-, -SO ₂ -, -SO ₂ NR ₄ -, - N(COR ₄ )-, and -N(SO ₂ R ₄ )-, wherein R ₄ is selected from H, C1-C6 branched or linear alkyl, phenyl and benzyl groups, wherein R ₄ has 0 to 1 spacing units selected from: -0-; -S-; -SO ₂ -; - C(O)O-; -OC(O)-; and an amine. Most preferably, the organic bridging group is -CONR ₄ -. Most preferably, wherein R ₄ is selected: from H and Me. Preferably, the Y group is bound directly to a carbon atom of an aromatic ring of the dye.

Ri is preferably selected from: H; Me; Et; Pr; CO ₂ C1-C4 branched and linear alkyl chains; phenyl; benzyl; CN; Cl; and, F. Most preferably Ri is H or Me.

A preferred dye-monomer is of the form:

wherein Ar is an aromatic or heteroaromatic group and Z is selected from: H; CH ₃ ; Cl; and, NHCOCH ₃ and W is selected from H; CH ₃ O; C ₂ H ₅ O; and, Cl.

Another preferred dye-monomer is of the form:

wherein the A and B ring are further substituted. Preferred groups include NH ₂ , NHAr, NHR ₅ , NR ₅ R ₆ , OH, Cl, Br, CN, OAr, NO ₂ , SO ₂ OAr, CH ₃ and NHCOC(Rl)=CH ₂ , wherein R ₅ and R ₆ are independently selected from C1-C8 branched, cyclic or linear alkyl which may be substituted by OH, OMe, Cl or CN.

Most preferably the dye is substituted at the 4, 5 or 8 position by at least one groups selected from NH ₂ , NHAr, and NHR ₅ , NR ₅ R ₆ . Most preferably when present OH and NO ₂ groups are at 4, 5 or 8 position and no more than 2 NO ₂ groups are present .

Suitable dyes may be prepared by acylation of an NH ₂ of an anthraquinone disperse dye, preferably selected from: disperse blue 1; disperse blue 5; disperse blue 6; disperse blue 9; disperse blue 19; disperse blue 28; disperse blue 40; disperse blue 56; disperse blue 60; disperse blue 81; disperse violet 1; disperse violet 4 and, disperse violet 8

A further example of a suitable dye is disperse blue 7. The dye monomer may be further substituted by uncharged organic groups having a total molecular weight of less than 400. Preferred uncharged organic groups are selected from: NHCOCH ₃ ; CH ₃ ; C ₂ H ₅ ; CH ₃ O; C ₂ H ₅ O; amine; Cl; F; Br; I; NO ₂ ; CH ₃ SO ₂ ; and, CN.

Synthesis of a variety of dye monomers is discussed in US4943617 (BASF), US5055602 (Bausch and Lomb) WO2005/021663 (Eastman), US5362812 (3M) .

Suitable and preferred dye monomers include:

and,

Further examples of dye monomers are: ALKENE COMONOMERS

The comonomer is preferably of the form:

wherein R ₂ and R3 are independently selected from: H, C1-C8 branched, cyclic and linear alkyl chains, C(O)OH,

CO2CI-CI8 branched and linear alkyl chains, -C(O)N (C1-C18) 2; -C (O)N(C1-C18)H; -C(0)NH2; heteroaromatic, phenyl, benzyl, polyether, cyano, Cl and F. Where C1-C18 is specified a preferred range is Cl to C4.

The R2 and R3 of the comonomer may be further substituted by charged and uncharged organic groups having a total molecular weight of less than 400. Preferred uncharged organic groups are selected from: NHCOCH ₃ , CH ₃ , C ₂ H ₅ , OH, CH ₃ O, C ₂ H ₅ O, amine, Cl, F, Br, I, NO ₂ , CH ₃ SO ₂ , and CN.

The phenyl, benzyl and alkyl chains may be substituted by further organic groups selected from: OH; F; Cl; alkoxy (preferably OCH ₃ ) , S0 ₃ ^~ , COOH, amine, quaternary amine, acid amide and ester. When phenyl or benzyl groups are present, the aromatic is not substituted by OH.

Examples of suitable co-monomers include. Preferred comonomer are indicated. hydrochloride

1 -sulfonate

Mixtures of co-monomer may be used. It is preferred that the >50wt%, more preferably >80wt%, of the co-monomers are selected from co-monomer that have a molecular weight of less than 300 and contains an amine, amide, OH, Sθ3 ^~ or COO ^~ group. Most preferably the co-monomer contains an amine group .

DYE POLYMER

Preferably, the dye polymer is blue or violet in colour. Preferably the dye polymer gives a blue or violet colour to the cloth with a hue angle of 250-345, more preferably 265 to 330, most preferably 270 to 300. The cloth used to determine the hue angle is white bleached non-mercerised woven cotton sheeting.

The polymer is made by co-polymerisation of the dye monomer with suitable unsaturated organic co-monomers.

Preferably the polymer contains 0.1 to 30 Molar% dye monomers units, preferably 2 to 15 Molar%.

The monomers within the polymer may be arranged in any suitable manner. For example as Alternating copolymers possess regularly alternating monomer residues; Periodic copolymers have monomer residue types arranged in a repeating sequence; Random copolymers have a random sequence of monomer residue types; Statistical copolymers have monomer residues arranged according to a known statistical rule; Block copolymers have two or more homopolymer subunits linked by covalent bonds. The polymer should have a molecular weight 500 and greater, preferably 2000 and greater, preferably 5000 and greater. In this context the molecular weight is the number average molecular weight. This is the ordinary arithmetic mean of the molecular weights of the individual macromolecules . It is determined by measuring the molecular weight of j polymer molecules, summing the weights, and dividing by j. Molecular weights are determined by Gel Permeations Chromatography.

It is preferred that the dye-polymer is soluble in surfactant solution. Specifically that at lg/L sodium dodecyl sulfate aqueous solution at pH=7 the dye polymer has a solubility of greater than lmg/L, preferably greater than 10mg/L. Water solubility is enhanced by the presence of hydroxy, amino and charged groups in the polymer, preferably anionic charged groups.

Preferably the polymer is of the form:

wherein X = Y-Dye , Preferably, a is greater than b (a>b) . More preferably the ratio a:b is from 99.9:0.1 to 70:30.

It is preferred that the dye-polymer has a number average molecular weight in the range from 500 to 500000, preferably from 1000 to 100000, more preferably 5000 to 50000.

For addition to a granular formulation the polymer dye may be added to the slurry to be spray dried or preferably added via post-dosed granules.

In a preferred embodiment the polymer dye powder obtained from the polymer dye synthesis is mixed with a Na2SO4 or NaCl or pre-prepared granular base or full detergent formulation to give a 0.1 to 20 polymer dye wt% mixture. This dry mix is then mixed into the granular formulation. The polymer dye powder is preferably formed by drying a liquid slurry or solution of the dye, for example by vacuum drying, freeze drying, drying in drum dryers, Spin Flash ® (Anhydro) , but most preferably by spray drying. The polymer dye powder may be ground before, during or after the making of the slurry. This grinding is preferably accomplished in mills, such as for example ball, swing, bead or sand mills, or in kneaders .

Other ingredients such as dispersants or alkali metal salts may be added to the liquid slurry. The polymer dye powder preferably contains 20 to 100 wt% of the dye.

Preferably, the polymer dye powder has an average particle size, APS, from 0.1 to 300 microns, preferably 10 to 100 microns. Preferably this is as measured by a laser diffraction particle size analyser, preferably a Malvern HP with 100 mm lens.

SURFACTANT

The composition comprises between 2 to 70 wt percent of a surfactant, most preferably 10 to 30 wt %. In general, the nonionic and anionic surfactants of the surfactant system may be chosen from the surfactants described "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 Ce 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 are usually water-soluble alkali metal salts of organic sulphates and sulphonates having alkyl radicals containing from about 8 to about 22 carbon atoms, the term alkyl being used to include the alkyl portion of higher 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 Cg to C20 benzene sulphonates, particularly sodium linear secondary alkyl Cio to Ci ₅ 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 preferred anionic detergent compounds are sodium Cu to Ci ₅ alkyl benzene sulphonates and sodium C ₁₂ to Cis alkyl sulphates. Also applicable are surfactants such as those described in EP-A-328 177 (Unilever), which shows resistance to salting-out, the alkyl polyglycoside surfactants described in EP-A-070 074, and alkyl monoglycosides .

Preferred surfactant systems are mixtures of anionic with nonionic detergent active materials, in particular the groups and examples of anionic and nonionic surfactants pointed out in EP-A-346 995 (Unilever) . Especially preferred is surfactant system that is a mixture of an alkali metal salt of a C16 to Cis primary alcohol sulphate together with a C12 to Ci ₅ primary alcohol 3 to 7 EO ethoxylate.

The nonionic detergent is preferably present in amounts greater than 10%, e.g. 25 to 90 wt % of the surfactant system. Anionic surfactants can be present for example in amounts in the range from about 5% to about 40 wt % of the surfactant system. In another aspect which is also preferred the surfactant may be a cationic such that the formulation is a fabric conditioner .

CATIONIC COMPOUND

When the present invention is used as a fabric conditioner it needs to contain a cationic compound.

Most preferred are quaternary ammonium compounds.

It is advantageous if the quaternary ammonium compound is a quaternary ammonium compound having at least one C12 to C22 alkyl chain.

It is preferred if the quaternary ammonium compound has the following formula:

R2

I ₊

R1—N-R3 X I R4 in which R ¹ is a C12 to C22 alkyl or alkenyl chain; R ² , R ³ and R ⁴ are independently selected from Ci to C ₄ alkyl chains and X ^~ is a compatible anion. A preferred compound of this type is the quaternary ammonium compound cetyl trimethyl quaternary ammonium bromide.

A second class of materials for use with the present invention are the quaternary ammonium of the above structure in which R ¹ and R ² are independently selected from C12 to C22 alkyl or alkenyl chain; R ³ and R ⁴ are independently selected from Ci to C ₄ alkyl chains and X ^~ is a compatible anion. A detergent composition according to claim 1 in which the ratio of (ii) cationic material to (iv) anionic surfactant is at least 2:1.

Other suitable quaternary ammonium compounds are disclosed in EP 0 239 910 (Proctor and Gamble) .

It is preferred if the ratio of cationic to nonionic surfactant is from 1:100 to 50:50, more preferably 1:50 to 20:50.

The cationic compound may be present from 1.5 wt % to 50 wt % of the total weight of the composition. Preferably the cationic compound may be present from 2 wt % to 25 wt %, a more preferred composition range is from 5 wt % to 20 wt %.

The softening material is preferably present in an amount of from 2 to 60% by weight of the total composition, more preferably from 2 to 40%, most preferably from 3 to 30% by weight.

The composition optionally comprises a silicone.

BUILDERS OR COMPLEXING AGENTS

Builder materials may be selected from 1) calcium sequestrant materials, 2) precipitating materials,

3) calcium ion-exchange materials and 4) mixtures thereof.

Examples of calcium sequestrant builder materials include alkali metal polyphosphates, such as sodium tripolyphosphate and organic sequestrants, such as ethylene diamine tetra- acetic acid.

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

Examples of calcium ion-exchange builder materials include the various types of water-insoluble crystalline or amorphous aluminosilicates, of which zeolites are the best known representatives, e.g. zeolite A, zeolite B (also known as zeolite P) , zeolite C, zeolite X, zeolite Y and also the zeolite P-type as described in EP-A-O, 384, 070.

The composition may also contain 0-65 % of a builder or complexing agent such as ethylenediaminetetraacetic acid, diethylenetriamine-pentaacetic acid, alkyl- or alkenylsuccinic acid, nitrilotriacetic acid or the other builders mentioned below. Many builders are also bleach- stabilising agents by virtue of their ability to complex metal ions.

Zeolite and carbonate (carbonate (including bicarbonate and sesquicarbonate) are preferred builders.

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

0.8-1.5 M ₂ O. Al ₂ O ₃ . 0.8-6 SiO ₂ where M is a monovalent cation, preferably sodium. These materials contain some bound water and are required to have a calcium ion exchange capacity of at least 50 mg CaO/g. The preferred sodium aluminosilicates contain 1.5-3.5 Siθ2 units in the formula above. They can be prepared readily by reaction between sodium silicate and sodium aluminate, as amply described in the literature. The ratio of surfactants to alumuminosilicate (where present) is preferably greater than 5:2, more preferably greater than 3:1.

Alternatively, or additionally to the aluminosilicate builders, phosphate builders may be used. In this art the term ^λ phosphate' embraces diphosphate, triphosphate, and phosphonate species. Other forms of builder include silicates, such as soluble silicates, metasilicates, layered silicates (e.g. SKS-6 from Hoechst) .

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

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] triazole, disodium 4,4'- bis { [ (4-anilino-6- (N methyl-N-2 hydroxyethyl) amino 1,3,5- triazin-2-yl) ] amino } stilbene-2-2 ' disulfonate, disodium 4 , 4 ' -bis { [ (4-anilino-6-morpholino-l , 3, 5-triazin-2-yl) ] amino } stilbene-2-2' disulfonate, and disodium 4, 4 '-bis (2- sulfostyryl) biphenyl .

It is preferred that the aqueous solution used in the method has a fluorescer present. When a fluorescer is present in the aqueous solution used in the method it is preferably in the range from 0.0001 g/1 to 0.1 g/1, preferably 0.001 to 0.02 g/1.

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 .

Perfume and top note may be used to cue the whiteness benefit of the invention.

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

POLYMERS

The composition may comprise one or more polymers. Examples are carboxymethylcellulose, poly (ethylene glycol) , poly (vinyl alcohol), polycarboxylates such as polyacrylates, maleic/acrylic acid copolymers and lauryl methacrylate/acrylic acid copolymers. Polymers present to prevent dye deposition, for example poly (vinylpyrrolidone) , poly (vinylpyridine-N-oxide) , and poly (vinylimidazole) , are preferably absent from the formulation .

ENZYMES

The laundry treatment composition may contain an enzyme.

Preferred enzymes are disclosed in WO 2007/087243 and WO

2007/087257.

Examples

Example 1 Synthesis of dye monomer

Reaction scheme:

1 , 4-Diaminoanthraquinone (DAQ) was purchased from Aldrich, (90% technical grade) and used as supplied.

The dye monomer was prepared by the reaction of DAQ (1,4- Diaminoaquinone) and Ac (acryloyl chloride) in the presence of sodium dicarbonate. A mixture of 150ml anhydrous THF, Ig

DAQ and 0.6g sodium dicarbonate was charged into 250ml three-necked round bottom flask equipped with a condenser, a dropping funnel, and a magnetic stirring bar. The flask was then maintained at R. T. while 0.38g Ac dissolved in 5ml anhydrous THF was added from the dropping funnel for 3h. The reaction mixture was stirred at 25 ⁰ C for another 2Oh. The reaction mixture was filtered to remove the insoluble solids occurred during the reaction process 2Oh later, the clear solution was dried by using rotary evaporation pressure reduced meter, then violet powder was obtained and washed with water for three times, the powder was completely dried under vacuum at 60 ⁰ C for 24h. The structure of DAQ-AC was confirmed using NMR and showed that the reaction had gone to greater than 88% completion. Consequently greater than 88% of the anthraquinones contained one NHCOCH=CH ₂ groups.

Example 2 Synthesis of dye containing polymers

Reaction Scheme:

A solution of 3g dimethyl amino ethyl methacrylate (DMAEMA) , 0.03g DAQ-Ac and 0.06g AIBN in 10ml toluene was charged into a dry N ₂ gas purged two-necked tube with a condenser and a magnetic stirring bar. The tube was sealed and placed in a regulated thermostat bath at 65 ⁰ C for 24hours. The solution was precipitated in five-fold excess of petroleum ether for three times after the reaction, followed by drying under vacuum at 40 ⁰ C for 24h. The composition of the co-polymers was regulated via the control of the primary usages of dye monomer and functional monomer. In the experiments, the amounts of dye monomer added were 1 wt %, 2 wt %, 5 wt % and 10 wt % respectively.

Example 3 UV-VIS of dye polymers

The UV-Vis spectra of the dye polymers of example 2 were recorded in demineralised water at lg/L dye polymer. The results are given in the table below.

Example 4 : Dye deposition experiments

Knitted white polyester (microfiber) and white woven non- mercerised cotton fabrics were used together in 4g/L of a detergent which contained 15% Linear Alkyl benzene sulfonate (LAS) surfactant, 30% Na ₂ CO ₃ , 40% NaCl, remainder minors included calcite and fluorescer and moisture. Washes were conducted in 6° French Hard water at room temperature with a liquor to cloth ratio of 30:1, for 30 minutes. Following the wash the cloths were rinsed twice in water, dried, their reflectance spectrum measured on a reflectometer and the colour expressed as CIE L a b values. The washes were then repeated until 4 washes had been accomplished. The experiment was repeated with the addition of the dye polymers of example 3. The dye polymers were dosed at 0.125wt% on formulation. Before and after the 1 ^st , 2 ^nd and 4 ^th wash the CIE L*a*b* values of the fabrics were recorded using a reflectometer (UV-excluded) . The deposition of the dye-polymers to the fabrics was expressed as the Δb value such that

Δb = b (control) -b (dye polymer)

+ve values indicate a blueing of the fabric, due to dye- polymer deposition.

The dye-polymers deposit to both cotton and polyester.

An added advantage is that the dye-polymer also facilitates soil removal and alter fabric feel.

Example 5 : Dye deposition experiments

The experiment of example 4 was repeated using the following polymers:

The results are shown in the table below: