Background The greying of white fabrics after several wash/wear cycles is a major problem in the Indian subcontinent. The causes include a high level of environmental soil in the atmosphere, calcium deposits originating from the wash process itself, and the use of blueing agents in the wash.

These blueing agents, which are sulphonated conjugated molecules or coloured clay-type materials, are deposited on the fabric and accumulate during repeated washes. White fabrics rapidly lose their new appearance after only a small number of wash/wear cycles and take on an unattractive grey appearance. This problem is exacerbated by the high level of sooty particulate soil in the atmosphere. Other sources of greying are fatty soil, for example sebum, skin cells, melanin, calcium soap deposits, clay soil, and iron oxides.

A similar dulling phenomenon has been noted with coloured fabrics. Further washing with the detergent products currently on the market merely appears to increases the problem further.

The present inventors have therefore sought to develop a process and product by means of which whiteness can be restored to a high level, preferably in a single treatment, and by means of which a high level of whiteness can be maintained over many wash/wear cycles. The process and product of the invention, if used on new fabrics, can also prevent or reduce the greying or dulling effect, so that a new appearance is maintained from the start.

Prior art JP 58 008 180A (Kao) discloses a process for removing coloured disinfectant stains from hospital clothing, in which the clothing is first machine-washed in an acid solution at pH 2.5-4.0, for example at 60°C, then machine- washed with a solution containing sodium hypochlorite bleach, for example at 40°C. The preferred acid for the first step is phosphoric acid, but citric acid may also be used. The acid solution used for the first step may contain a neutral detergent.

GB 2 095 254A (Kreussler) discloses a composition for reducing discolouration of textiles during washing or dry cleaning, the composition comprising tertiary amine salts of citric acid or tricarballylic acid.

WO 96 21714A (Procter & Gamble) discloses a process for improving the colour fidelity of coloured and white fabrics,

which comprises rinsing the fabrics in water containing a chelating agent for copper or nickel ions plus a chlorine scavenger. The chelating agent is preferably ethylenediamine disuccinate. The chlorine scavenger is preferably ammonium chloride or a primary or secondary amine.

WO 97 28207A and WO 97 28208A (Procter & Gamble) disclose heavy metal ion control agents for use in laundry detergent compositions, to prevent the fading of coloured fabric and the build up of yellow or grey colour on white fabric. The heavy metal ion control agents are modified polyamines.

JP 61 062 600A (Kao) discloses a detergent composition for preventing the yellowing of fabrics due to ferrous ions, comprising citric acid, isocitric acid or their salts plus optionally polyethylene glycol, surfactants, builders, bleaches and other conventional ingredients.

EP 534 525A (Unilever) discloses a granular detergent composition containing particulate citric acid, plus anionic and/or nonionic surfactants, sodium carbonate, other builder, and preferably also foam depressing agent and bleach components.

Definition of the invention The present invention provides a process for the treatment of textile fabrics to improve, restore or maintain whiteness, which comprises the steps of: (i) allowing the fabrics to soak for at least 1 minute in a first aqueous liquor comprising (i) (a) an effective amount of a material capable of converting deposited blueing agent to a colourless product, and of the same or a different material capable of binding Ca and Fe ions, and (i) (b) optionally a surfactant, (ii) allowing the fabrics to soak for at least 1 minute in a second aqueous liquor comprising (ii) (a) a bleach and (ii) (b) optionally a surfactant, (ii) (c) optionally sodium carbonate, (ii) (d) optionally a detergency builder, and (iii) rinsing the fabrics in water.

The invention further provides a product for the treatment of textile fabrics to improve, restore or maintain whiteness, comprising two separately packaged particulate compositions, wherein:

the first particulate composition (i) comprises (i) (a) from 50 to 100 wt% of a material capable of converting deposited blueing agent to a colourless product, and the same or a different material capable of binding Ca and Fe ions, and (i) (b) optionally from 0 to 15 wt% of a surfactant; and the second particulate composition (ii) comprises (ii) (a) from 1 to 100 wt% of a bleach, (ii) (b) optionally from 0 to 15 wt% of a surfactant, (ii) (c) optionally from 0 to 99 wt% of sodium carbonate and/or a filler salt, (ii) (d) optionally from 0 to 50 wt% of a detergency builder.

The present invention further provides a product for the treatment of textile fabrics to improve, restore or maintain whiteness, comprising two separately packaged particulate compositions, wherein: the first particulate composition (i) has a pH (of a 1% solution in demineralised water at 25°C) of less than 5 and comprises: (i) (a) from 50 to 100 wt% of a material capable of converting deposited blueing agent to a colourless product, and the same or a different material capable of binding Fe ions, and (i) (b) optionally from 0 to 30 wt% of a surfactant;

(i) (c) optionally from 0 to 10 wt% of an oxidising agent capable of masking and/or neutralising sulphurous odours, (i) (d) optionally from 0 to 10 wt% of a bleach stable and effective at a pH below 5.0, and other minor ingredients to 100 wt%, and the second particulate composition (ii) comprises (ii) (a) from 1 to 100 wt% of a bleach, (ii) (b) optionally from 0 to 30 wt% of a surfactant, (ii) (c) optionally from 0 to 99 wt% of an alkaline buffering agent, (ii) (d) optionally from 0 to 50 wt% of one or more builder and/or filler salts, (ii) (e) optionally from 0 to 5 wt% of a sequestrant bleach stabiliser, (ii) (f) optionally from 0 to 5 wt% of a fluorescer, (ii) (g) optionally an effective amount of one or more detergent enzymes, and other minor ingredients to 100 wt%.

Detailed description of the invention The first aspect of the invention is a wet treatment process. In this process the fabrics are soaked successively in two different aqueous liquors and then rinsed. Optionally the fabrics may be rinsed between the two soaking steps.

A preferred process in accordance with the present invention comprises the steps of:

(i) allowing the fabrics to soak for at least 1 minute in a first aqueous liquor having a pH not exceeding 5.0 and comprising (i) (a) an effective amount of a material capable of converting deposited blueing agent to a colourless product, and of the same or a different material capable of binding Fe ions, and (i) (b) optionally a surfactant, (i) (c) optionally an effective amount of an oxidising agent capable of masking and/or neutralising sulphurous odours, (ii) (d) optionally a bleach stable and effective at a pH below 5.0, (ii) allowing the fabrics to soak for at least 1 minute in a second aqueous liquor comprising (ii) (a) a bleach, (ii) (b) optionally a surfactant, (ii) (c) optionally an alkaline buffering agent, (ii) (d) optionally one or more builder and//or filler salts, (ii) (e) optionally a sequestrant bleach stabiliser, (ii) (f) optionally a fluorescer, (ii) (g) optionally one or more detergent enzymes, (iii) rinsing the fabrics in water.

The treatment may be carried out on either clean or soiled fabrics. The treatment itself can incorporate laundering to a greater or lesser degree, depending on the amounts of surfactants and other cleaning ingredients present in the two aqueous liquors, and it may be employed either instead of, or in addition to, conventional laundering. Preferably,

the treatment is carried out in addition to conventional laundering, and the fabrics are clean.

The process of the invention is especially useful, as a supplement to the normal laundry process, for the restoration or"rejuvenation"of white fabrics that have become grey. It has been found that the reflectance of greyed fabrics treated by the process of the invention can be very substantially increased. For example, when the process is applied to greyed fabrics having an initial reflectance at 460 nm, R (460*), no greater than 65, an increase in reflectance at 460 nm, AR (460*), of at least 6, preferably at least 10, units has been achieved over five treatments. Even greater increases may be observed in reflectances at 600 nm.

The process of the invention may also be used to maintain the whiteness of new fabric and prevent the greying process.

Although intended primarily for the treatment of white fabrics, the process of the invention may also be useful for restoring or maintaining the colour fidelity of coloured fabrics.

The process of the invention is suitable for carrying out by hand, using simple utensils such as buckets or bowls as are usually used in laundering fabrics by hand. However, the process may also be carried out by machine.

The second aspect of the invention is a product comprising two separately packaged particulate products which may be used to prepare the two aqueous liquors used in the process of the invention.

The first aqueous liquor The first aqueous liquor contains as an essential ingredient a material capable of converting deposited blueing agent to a colourless form, and a material (the same or a different material) capable of binding Fe ions, and advantageously capable also of binding Ca ions.

Preferably a material fulfilling both functions is used.

The material or combination of materials must be present in an effective amount.

The conversion of blueing agent (a sulphonated conjugated molecule or coloured clay-type material) to a colourless form may be effected by reduction. The active ingredient in the first aqueous liquor is therefore preferably a reducing agent.

Suitable materials include water-soluble solid organic carboxylic acids, for example, citric acid, oxalic acid, tartaric acid, malonic acid, succinic acid, ascorbic acid, or water-soluble salts of these acids. Salts containing two or more carboxyl groups are especially preferred.

Alternatively water-soluble solid acid salts such as sodium dihydrogen phosphate dihydrate, NaH2PO4. laq, or tetrabutylammonium hydrogen sulphate, (C4H9) 4N. HS04, may be used.

Examples of some suitable acidic materials include the following: Acid/salt Formula DL-Lactic acid H3C-CHO-COOH Glycolic acid H2-C-OH-COOH Fumaric acid HOOC-CH=HC-COOH Malonic acid HOOC-CH2-COOH Malic acid HOOC-CH2-CHOH-COOH Salicylic acid OH- (C6H4)-COOH Oxalic acid 2aq HOOC-COOH Succinic HOOC-CH2-CH2-COOH Benzoic acid (C6H4)-COOH Tartaric HOOC-HCOH-HCOH-COOH Adipic HOOC-CH2-CH2-CH2-CH2-COOH Glutaric acid HOOC-CHOH-CHOH-CHOH-COOH Glycine H2-N-CH2-COOH Sokalan DCS Mixed adipic glutaric succinic acids Citric acid laq HO- (-C-COOH) 3 Ascorbic acid HO-CH2-CHOH-CH-CH=CH- C=0.. 0 (3-6) Boric HBO3 Asparagine laq HOOC-CH2-NH2-CH2-COOH Sodium dihydrogen NaH2PO4 phosphate 2aq Arginine H2N-C (=NH- (CH2) 3-CH (NH2)- COOH SalicylOH-(C6H4)-COO-(C6H4)-COOH salicylic acid Cysteine HS-CH2-CH (NH2)-COOH

The first aqueous liquor has a relatively low pH, lower than 5, and advantageously in the range of from 3.5 to 4.5, most preferably about 4.0. However, lower pH values, for example, 2 to 3.5, are also within the scope of the invention.

According to a preferred embodiment of the invention, the material (i) (a) is an organic acid used in admixture with a corresponding water-soluble salt, preferably a sodium salt.

The pH may then be controlled by choice of the ratio of free acid to salt.

Thus a preferred material (i) (a) in accordance with the invention is a solid organic carboxylic acid, preferably containing two or more carboxyl groups, optionally in admixtures with a water-soluble salt thereof.

The preferred material (i) (a) for use in the present invention is citric acid, optionally and more preferably used in admixture with sodium citrate.

The concentration of the material (or combination of materials) (i) (a) in the first aqueous liquor is preferably at least 1 g/litre, and more preferably at least 3 g/litre.

Desirably the first aqueous liquor also contains an effective amount of an oxidising agent capable of masking and/or neutralising sulphurous odours. Such odours may be generated when the blueing agent is converted to a colourless form. Suitable materials are especially oxidative bleaches, preferably selected from alkali metal and alkaline earth metal iodates, peroxomonosulphates, benzenecarboperoxoates and monoperoxyphthalates, and hydrogen peroxide. Especially preferred are alkali metal iodates, more especially potassium iodate.

The amount required to neutralise sulphurous odours may be determined by means of a lead acetate titration test, which is carried out as follows. A monitor is prepared by impregnating a 1 cm x 10 cm strip of Whatman IPS phase- separating filter paper (silicone treated) with lead acetate solution (1 g of lead acetate trihydrate in 100 ml demineralised water). A fabric monitor is placed in 100 ml

sample of the treatment liquor (first aqueous liquor) in a 400 ml beaker, the lead acetate strip is moistened with demineralised water and placed above the treatment liquor, and the beaker is closed with a transparent lid. If hydrogen sulphide is formed during the treatment, the lead acetate strip becomes black/brown due to the formation of lead sulphide, and this indicates that the liquor contains an insufficient amount of the oxidising agent.

Advantageously the first aqueous liquor may contain a bleach stable and effective at a pH below 5.0. By"stable and effective"is meant that the bleach must be stable in a product on storage at a pH below 5.0, soluble when the product is dissolved in water, and function effectively as a bleach at the pH of the product.

Some but not all of the materials disclosed above as odour- masking or odour-neutralising agents are also stable and effective bleaches at a pH below 5.0. However, if the chosen oxidising agent is, for example, potassium iodate, it may be preferred for an additional bleach stable at low pH also to be present. Preferred bleaches are alkali metal dichlorocyanurates.

Materials that may function both as odour-masking or neutralising agents and as stable and effective bleaching agents at a pH below 5.0 include magnesium monoperoxyphthalate and potassium benzenecarboperoxoate.

The first aqueous liquor may also advantageously contain one or more surfactants. Anionic and/or nonionic surfactants are preferred, especially anionic surfactants used alone and combinations of anionic and nonionic surfactants in which the anionic surfactant predominates. A preferred

surfactant system comprises an anionic surfactant selected from linear alkylbenzene sulphonate and alpha-olefin sulphonate, optionally together with at least one ethoxylated Ca-C20 alcohol nonionic surfactant having an average degree of ethoxylation of from 2 to 10.

Other ingredients, for example perfumes, may be present, generally in minor amounts.

In the first step of the process of the invention, the fabrics are allowed to soak in the first aqueous liquor for at least 1 minute, preferably from 1 to 60 minutes, more preferably from 10 to 45 minutes, and most preferably from 15 to 30 minutes.

With or without an intermediate rinse, the fabrics are then allowed to soak in the second aqueous liquor.

The second aqueous liquor The second aqueous liquor contains as an essential ingredient a bleach. Other ingredients including surfactants and alkaline buffering agents may if desired be present, but that is not essential.

Suitable bleaches include chlorine bleaches such as alkali metal hypochlorite, organic chloramides (eg alkali metal dichlorocyanurate (DCCA) or trichlorocyanurate); peracids, for example, N, N'-phthaloylaminoperoxycaproic acid (PAP), diperdodecanoic acid (DPDA); inorganic persalts, for example, alkali metal perborate or percarbonate, together with a bleach activator (peracid precursor) such as alkylsulphophenyl carbonate (ASPC),

cholylsulphophenylcarbonate (CSPC), or SNOBS and similar materials. If desired, two or more bleaches may be used in combination.

Preferred bleaches are alkali metal hypochlorite, alkali metal dichlorocyanurate (DCCA), alkali metal perborate, and N, N'-phthaloylaminoperoxycaproic acid (PAP), and combinations thereof. Especially preferred bleaches are sodium DCCA, PAP, and combinations thereof.

Advantageously the second aqueous liquor may also contain a bleach stabiliser (heavy metal sequestrant), for example, an aminopolycarboxylate or aminopolyphosphonate. Preferred materials include EDTA, NTA, EDDS, and EDTMP and DETPMP (Dequests (Trade Mark)).

A sequestrant is desirable or preferred when the bleach system includes PAP, but may be omitted if the bleach is NaDCCA.

The concentration of bleach in the second aqueous liquor is preferably at least 0.05 g/litre, more preferably at least 0.1 g/litre and most preferably at least 0.2 g/litre.

Surfactants may also be present. Especially preferred are anionic and/or nonionic surfactants. As in the first aqueous liquor, anionic surfactants alone and anionic/nonionic combinations in which the anionic surfactant predominates are preferred.

The second aqueous liquor may also contain an alkaline buffering agent, which may suitably be selected from sodium carbonate, sodium bicarbonate, sodium sesquicarbonate, sodium silicate and combinations of these.

It may also contain one or more builder and/or filler salts, suitably selected from sodium tripolyphosphate, other sodium phosphates, sodium sulphate, and combinations of these.

Thus the second aqueous liquor may be purely a bleach solution; or may to a greater or lesser extent contain other detergent or cleaning ingredients. At one extreme the second aqueous liquor may be generated purely by dissolving bleach in water; at the other extreme, the seocnd aqueous liquor may be generated by dissolving or dispersing a fully formulated bleaching detergent composition, or a fully formulated non-bleaching detergent composition plus separate bleach, in water.

In the second step of the process of the invention, the fabrics are allowed to soak in the second aqueous liquor for a period of at least 1 minute, preferably from 1 to 60 minutes, more preferably from 10 to 30 minutes.

In a final step, the fabrics are rinsed in water.

The product of the invention In the product of the invention, a first particulate composition is used to prepare the first aqueous liquor.

This suitably contains: from 50 to 100 wt% (in total) of the material (s) capable of converting blueing agent to a colourless form and/or binding Fe ions;

optionally from 0 to 30 wt% (eg 1 to 30 wt%) of one or more surfactants; optionally from 0 to 10 wt% (eg 0.5 to 10%) of an oxidising agent capable of masking and/or neutralising sulphurous odours, optionally from 0 to 10 wt% (eg 0.5 to 10 wt%) of a bleach stable and effective at a pH below 5.0, and optionally other minor ingredients.

The balance if any may be constituted by an inert filler such as sodium sulphate.

As oxidising agent, the first particulate composition preferably contains from 0.5 to 10 wt% of potassium iodate, magnesium monoperoxyphthalate or potassium benzenecarboperoxoate. Potassium iodate is especially preferred and is effective in an amounts of from 0.5 wt%, preferably from 0.5 to 2 wt%.

As a bleach stable and effective at a pH below 5.0, the first particulate composition preferably contains from 0.5 to 10 wt%, preferably from 0.5 to 6 wt% and more preferably from 0.5 to 4 wt%, of alkali metal dichlorocyanurate.

The first particulate composition has a pH (of a 1% solution in demineralised water at 20°C) not greater than 5, preferably within the range of from 2.0 to 5.0, more preferably within the range of from 3.5 to 4.5, and desirably about 4.0.

As previously indicated, a surfactant system is preferably present.

Preferred compositions may, for example, contain the following ingredients in the following concentration ranges (suitable and preferred, wt%): Citric acid 35-95 40-55 Sodium citrate 0-50 30-45 Anionic surfactant (LAS or AOS) 0-25 3-25 Nonionic surfactant (eg C12 7EO) 0-5 0-5 Potassium iodate 0-2 0.5-1.5 NaDCCA 0-6 0.5-3 Perfume 0.05-1.0 0.1-0.5 The first particulate composition may suitably be used at a dosage of from 2 to 20 g, preferably from 5 to 10 g, per 250 g fabrics to prepare the first aqueous liquor.

A second particulate composition is used to prepare the second aqueous liquor. This product comprises: from 1 to 100 wt% (preferably from 1 to 20 wt%) of the bleach; optionally from 0 to 30 wt% (preferably from 1 to 30 wt%) of surfactant, preferably anionic and/or nonionic surfactant; optionally from 0 to 99 wt% (preferably from 1 to 99 wt%) of an alkaline buffering agent, optionally from 0 to 50 wt% (preferably from 1 to 50 wt%) of one or more builder and/or filler salts,

optionally from 0.1 to 5 wt% of a sequestrant bleach stabiliser, optionally from 0.01 to 5 wt% of a fluorescer, optionally an effective amount of one or more detergent enzymes, and minor ingredients to 100 wt%.

The second particulate composition may suitably be used at a dosage of from 2 to 20 g, preferably from 5 to 10 g, per 250 g of fabrics.

Preferred compositions may, for example, contain the following ingredients in the following concentration ranges (suitable and preferred, weight %) : NaDCCA or PAP 1-10 2-6 Sodium carbonate (soda ash) 5-90 5-10 Sodium bicarbonate 0-60 5-10 Sodium tripolyphosphate 5-30 10-20 Sodium sulphate 0-30 10-25 Anionic surfactant (LAS or AOS) 10-30 20-25 Nonionic surfactant (eg C12 7EO) 0-5 0 Sequestrant (eg Dequest 2047) 0-5 0.1-2 Fluorescer, eg Tinopal CBS-X 0.1-1 0.2-0.5 Protease granules 0-5 1-3 Cellulase granules 0.5 1.3 Perfume 0.05-1.0 0.1-0.5

Packaging and presentation In the product of the invention, the two particulate compositions are separately packaged. According to a preferred embodiment of the invention, they are packaged in unit dose form so that a single dose of each composition may be used per treatment. Especially preferred are sachets.

Opening sachets of paper or nonwoven fabric are preferred.

Sachets suitable for containing detergent powders and similar materials are widely disclosed in the prior art.

Preferably, the sachets containing the two particulate compositions are visually distinct, for example, colour coded. The sachets may then be packed together in outer packaging, for example, a bag or carton, possibly grouped in pairs, while remaining readily distinguishable.

EXAMPLES The invention will now be described in more detail in the following non-limiting Examples, in which all parts and percentages are by weight unless otherwise stated.

Trade marks are indicated by an asterisk.

EXAMPLE 1: product of the invention A first particulate composition l (i) had the following formulation: Particulate Composition 1 (i) wt% Citric 94.5 Nonionic surfactant C12-C15 5.0 Lemon 0.5

7.5 g doses of Composition l (i) were packaged in sachets of nonwoven fabric. The 1% solution pH of Composition l (i) was 2.4-2.5.

A second particulate composition l (ii) had the following formulation: Particulate Composition l (ii) wt% Sodium dichlorocyanurate (NaDCCA) 6 Nonionic surfactant C12-Cl5 7EO 5 Sodiumtripolyphosphate 4 Sodiumcarbonate 85

7.5 g doses of Composition 2 were packaged in sachets of nonwoven fabric.

EXAMPLE 2: product of the invention A first particulate composition 2 (i) having a 1 wt% solution pH of 4.0 had the following formulation: Particulate Composition 2 (i) wt% Citric acid 50.00 Trisodium citrate 2aq 43.30 Linear alkylbenzene sulphonate 98% 5.00 Nonionic surfactant C12-Cls 7EO 0.50 Potassium iodate 1.00 Perfume 0.20

A second particulate composition 2 (ii) had the following formulation: Particulate Composition 2 (ii) wt% N,N'-phthaloylaminoperoxycaproic 11.13 acid (PAP) (34%) Sodium bicarbonate 6.60 Sodium carbonate 6.60 Sodium tripolyphosphate (anhydr) 16.31 Sodium silicate 9.90 Sodium sulphate 25.12 Linear alkylbenzene sulphonate 98% 23.25 Ca EDTMP (Dequest* 2047) 0.50 Fluorescers Tinopal*DMS-X and CBS-X 0.42 Perfume 0.20 7.5 g doses of Compositions 2 (i) and 2 (ii) were packaged in sachets of nonwoven fabric.

EXAMPLE 3: product of the invention A first particulate composition 3 (i) having a 1 wt% solution pH of 4.0 had the following formulation: Particulate Composition 3 (i) wt% Citric acid 41.40 Trisodium citrate 2aq 35.60 Linear alkylbenzene sulphonate 98% 19.80 Na DCCA 2.00 Potassium iodate 1.00 Perfume 0. 20 A second particulate composition 3 (ii) had the following formulation:

Particulate Composition 3 (ii) wt% PAP 34% 11.10 Sodium carbonate (anhydr) 6.60 Sodium 6.60 Sodium tripolyphosphate (anhydr) 16.31 Sodium 9.90 Sodium 21.12 Linear alkylbenzene sulphonate 98% 23.25 Ca EDTMP (Dequest 2047) 0.50 Fluorescers Tinopal* DMS-X and CBS-X 0.42 Protease (Savinase*) 2.00 Cellulase (Celluzyme*) 2.00 Perfume0.20 7.5 g doses of Compositions 3 (i) and 3 (ii) were packaged in sachets of nonwoven fabric.

EXAMPLE 4: rejuvenation of greyed fabrics (single treatment) The fabrics to be treated were cotton vests and polyester/cotton shirts which had been subjected to 10 wash/wear cycles, the wash being by hand using a laundry detergent powder commercially available in India.

The contents of a sachet of particulate composition l (i) of Example 1 (7.5 g) were dissolved in 1.5 litres of water in a bucket to prepare a first aqueous liquor. The pH of the liquor was 2.6-2.7 and the concentration of the active ingredient, citric acid, was 4.725 g/litre. The greyed garments (total weight of load 250 g) were placed in the aqueous liquor and allowed to soak for 15-30 minutes.

The contents of a sachet of particulate composition l (ii) of Example 1 (7.5 g) were dissolved in 1.5 litres of water in a second bucket to prepare a second aqueous liquor. The concentration of bleach (NaDCCA) in the second aqueous liquor was 0.3 g/l.

The garments were removed from the first bucket, wrung out by hand to remove excess liquid, placed in the second bucket, and allowed to soak for 15 minutes.

Finally, the garments were removed from the second bucket, wrung out, and rinsed in clean water in a third bucket.

The average reflectance values at 460 and 600 nm before and after treatment were as follows: SHIRTSVESTS 460 nm 600 nm460 nm 600 nm Befoe 41.066.952.450.9 After56.777.379.158.2 7.315.710.426.7Difference#R

Example 5: rejuvenation of greyed fabrics (multiple treatment) For this experiment, the load was of cotton vests (250 g).

The average initial reflectances were 58.4 at 460 nm and 52.8 at 600 nm.

The vests were subjected to the treatment described in Example 3, allowed to dry, then subjected again to the treatment. This process was repeated to give a total of five treatments. The reflectance was measured at each stage, and the increases are given below. AR (460 nm) AR (600 nm) After 1 11.35.6 After 2 12.35.9 After 3 9.58.6 After 4 treatments 15.9 After 5 18.111.4

Example 6: Rejuvenation of greyed fabrics (single treatment) The procedure of Example 4 was repeated using the formulation of Example 2. The reflectance results were as follows: SHIRTS VESTS 460 nm 600 nm 460 nm 600 nm Beforetreatment 54. 00 57. 09 52. 63 58.59 Aftertreatment 59. 66 62. 93 60. 06 64.70 Difference AR 5. 66 5. 84 7. 43 6.11

Example 7: Rejuvenation of greyed fabrics (single treatment) The procedure of Example 4 was repeated using the formulation of Example 3. The reflectance results were as follows: SHIRTSVESTS 460 nm 600 nm600460 nm Before treatment54.85 57.9152.07 After64.7361.2465.5262.09 7.246.819.178.57Difference#R

Example 8: Effect of pH in step (i) Using the first particulate composition 3 (i) of Example 3, the effect of pH on performance in the first step of the process of the invention (as reflectance increase at 600 nm on an Indian consumer vest) was studied. The results are shown in the following table: pH of citric acid/Na citrate #R (600*) 2.3218.2 3.0517.3 3.4516.8 3.8316.2 4.2514.4 4.819.2 5.374.6 6.064.5 7.860.5 These results illustrate clearly the benefits of operating at pH values below 5.0.

Example 9: effect of enzymes in step (ii) The performance of the composition of Example 3 (ii) was compared to the performances of corresponding compositions containing lower levels of enzymes, and a control product without either enzyme (the balance being made up with sodium sulphate). The results (AR 460* differences on Indian consumer vests) were as follows: Protease (wt%) Cellulase (wt%) AAR 460* l 0 0 (0) 0.5 0. 5 + 2.1 1.0 1. 0 + 2.7 +3.02.02.0

These results demonstrate clearly the benefit of including 2.0 wt% of each enzyme in the composition of Example 3 (ii).

Example 10: alternatives to citric acid The effectiveness of a number of organic and inorganic acids in increasing the reflectance at 600 nm of a monitor which was an Indian consumer vest treated with blueing agent was compared.

To prepare the monitor, the vest was soaked in a solution of 0.5 g blueing agent (Reckitt's Blue*) in 3 litres of water (24° French hard) for 3 minutes, rinsed and dried, this procedure being repeated five times.

The tests were carried out at a concentration in water of 4.76 mmole/100 ml. Each acid was tested at its own pH, except for HCl at pH 3.

In the following table the acids are ranked in order of decreasing weight-effectiveness. Acid/salt Formula Mol pH pH Effect Effect Wt start end AR (600*) #R(600*)/ Mol Wt HClHCl/pH=1.1 36.5 1.1 1.1 14.6 0.40 DL-LacticDL-LacticH3C-CHO-COOH 2.620.10.222.5 acid Glycolic H2-C-OH-COOH 76.1 2.3 2.4 14.9 0.20 acid Fumaric HOOC-CH=HC-116.1 2.3 2.3 18.0 0.16 acid COOH Malonic HOOC-CH2-COOH 104.1 1.9 1.9 15.7 0.15 acid HClHCl/pH=3.0 HCl 36.5 3.0 3.7 5.5 0.15 Malic134.12.42.518.90.14HOOC-CH2- CHOH-COOH Salicylic OH- (C6H4)- 138.1 2.3 2.1 17.3 0.13 acid COOH Oxalic acid HOOC-COOH 126.1 1.3 1.3 16.1 0.13 2aq 118.1SuccinicHOOC-CH2-CH2- 2.6 2.7 0.12 acid COOH Benzoic (C6H4)-COOH 122.1 2.6 2.8 13.6 0.11 acid Tartaric HOOC-HCOH-150.1 2.2 2.3 14.4 0.10 acid HCOH-COOH Adipic acid HOOC-CH2-CH2-146.1 3.0 3.0 13.5 0.09 CH2-CH2-COOH Glutaric HOOC-CHOH-132.1 2.9 3. 0 12.0 0.09 acid CHOH-CHOH- COOH Glycine H2-N-CH2-COOH 75.1 4.8 5.3 6.9 0.09 Sokalan DCS Mixed adipic 192.0 2.8 3. 0 16. 0 0.08 glutaric succinic Citric acid HO-(-C-COOH)3 210.1 2.0 2.1 14.5 0.07 laq Ascorbic HO-CH2-CHOH- 176. 1 2.6 2.7 12.5 0.07 acid CH-CH=CH- C=0.. 0 (3-6) Boric acid HBO3 61.8 4.2 5.5 3.2 0.05 150.14.14.64.90.03AsparagineHOOC-CH2-NH2- laq CH2-COOH NaH2PO4. laq NaH2PO4 138.0 4.6 4.9 4.7 0.03 Arginine H2N-C (=NH-174.2 10.7 10. 7 4. 6 0.03 (CH2) 3- CH(NH2)-COOH Salicyl OH- (C6H4)-258.2 3.7 3.7 6.2 0.02 salicylicCOO-(C6H4)- acid COOH Cysteine HS-CH2- 121. 2 4.7 5.9 2.2 0.02 CH (NH2)-COOH