WO2023041739A1

WO2023041739A1 - Laundry composition for the removal of stains

Info

Publication number: WO2023041739A1
Application number: PCT/EP2022/075835
Authority: WO
Inventors: Valeria BALDAN; Enrico GIUSTO; Anna MARCHIANI
Original assignee: Reckitt Benckiser Vanish B.V.
Priority date: 2021-09-16
Filing date: 2022-09-16
Publication date: 2023-03-23

Abstract

The present invention relates to a laundry composition comprising an oxygen-based bleach and a dye transfer inhibitor system comprising a homopolymer of 1-vinyl-2- pyrrolidone (PVP) and an alkali metal salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride. It also relates to a method of washing a garment using the laundry composition and to the use of the laundry composition for the removal of stains from a garment, and preferably for the reduction or inhibition of malodour in a garment.

Description

Laundry composition for the removal of stains

The present invention relates to a laundry composition comprising an oxygen-based bleach and a dye transfer inhibitor system comprising a homopolymer of 1-vinyl-2- pyrrolidone (PVP) and an alkali metal salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride. It also relates to a method of washing a garment and to a use of a laundry composition for the removal of stains from a garment, and preferably for the reduction or inhibition of malodour in a garment.

Background

Consumers associate desirability and wearability of a garment with characteristics such as absence of stains, or absence or reduction of colour fading, or reduction or inhibition of malodour. It is preferred when all characteristics are achieved in a simple way.

The removal of stains is achieved using bleaching agents, surfactants and/or enzymes. For example, enzymatic stains require enzymes, oil-based stains require enzymes or a combination of surfactants and bleachable stains require a bleaching agent to remove them.

Although bleachable stains may be removed with bleaching agents, this often leads to discoloration or dye transfer from a garment. Therefore, it is not an easy task to remove bleachable stains whilst inhibiting colour fading or dye transfer.

In addition, some stains contain polyphenols, which are naturally occurring compounds having multiples of phenol units. Examples of polyphenol-containing foods are tea, red wine, curry, and chocolate. Some of these compounds have been used as dyes and for tanning garments, which gives an idea that it is complicated to remove stains of polyphenolic compound soils from a garment.

For the removal of stains containing polyphenols, bleaching agents, preferably in combination with enzymes, are normally used. Again, this often leads to discolouration or dye transfer from the garment being treated.

To avoid discolouration or dye transfer from a garment, dye transfer inhibitors are commonly used. The activity of dye transfer inhibitors can be reduced by traditional bleaching agents, such as hydrogen peroxide, peroxide compounds and/or peroxyacids. Some solutions have been proposed to achieve stain removal of compositions comprising dye transfer inhibitors. EP1268731 describes bleaching compositions based on atmospheric oxygen, without hydrogen peroxide or a source of hydrogen peroxide, comprising a ligand which forms a complex with a transition metal. EP0964910 describes compositions comprising a xylan degrading enzyme. EP0907703 describes compositions comprising modified polyamines to provide dye transfer inhibition in the presence of bleaching agents.

Therefore, there is a need for a laundry composition comprising an oxygen-based bleach, such as hydrogen peroxide, which provides improved stain removal, in particular bleachable stains. Preferably, the composition should also provide reduction or inhibition of malodour in a garment. The person skilled in the art will recognise that, because of regulatory constraints, it is not possible to just increase the amount of bleach in a composition. Therefore, the amount of the oxygen-based bleach in the laundry composition should not increase, but the performance of the composition should improve.

It is an object of the present invention to provide a laundry composition that provides a solution for this need.

To this end, the present disclosure provides a laundry composition comprising an oxygen-based bleach and a dye transfer inhibitor system comprising a homopolymer of 1-vinyl-2-pyrrolidone (PVP) and an alkali metal salt of poly (N-carboxymethyl-4- vinylpyridinium) chloride.

Summary of the invention

In a first aspect, the present invention relates to a laundry composition comprising an oxygen-based bleach and a dye transfer inhibitor system comprising a homopolymer of 1-vinyl-2-pyrrolidone (PVP) and an alkali metal salt of poly (N-carboxymethyl-4- vinylpyridinium) chloride.

In one embodiment, the homopolymer of 1-vinyl-2-pyrrolidone (PVP) has a molecular weight of between 10 000 g/mol and 200 000 g/mol, preferably between 20 000 g/mol and 100000 g/mol, more preferably between 30000 g/mol and 50 000 g/mol, even more preferably between 35 000 g/mol and 45 000 g/mol.

In a preferred embodiment, the alkali salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride is a sodium salt.

In an embodiment, the composition comprises between 1 wt.% and 15 wt.% of the oxygen-based bleach, based on the total weight of the composition, preferably between 2 wt.% and 14 wt.% more preferably between 3 wt.% and 13 wt.%, even more preferably between 4 wt.% and 12 wt.%, most preferably between 5 wt.% and 11 wt.%.

In a preferred embodiment, the oxygen-based bleach is hydrogen peroxide or a precursor of hydrogen peroxide. Preferably the oxygen-based bleach is hydrogen peroxide.

In an embodiment, the composition comprises between 0.01 wt.% and 10 wt.% of the dye transfer inhibitor system, based on the total weight of the composition, preferably between 0.05 wt.% and 7.5 wt.%, more preferably between 0.1 wt.% and 5 wt.%, even more preferably between 0.2 wt.% and 2.5 wt.%.

In another embodiment, the weight ratio between the homopolymer of 1-vinyl-2- pyrrolidone (PVP) and the alkali metal salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride is between 0.01 :1 and 2:1 , preferably between 0.05:1 and 1 :1 , more preferably between 0.1 :1 and 0.8:1 , even more preferably between 0.15:1 and 0.75:1 , most preferably between 0.2:1 and 0.7:1.

In an embodiment, the composition further comprises between 0.5 wt.% and 70 wt.% of one or more surfactants, based on the total weight of the composition, preferably between 1 wt.% and 50 wt.%, more preferably between 2.5 wt.% and 40 wt.%, even more preferably between 5 wt.% and 30 wt.%, most preferably between 10 wt.% and 20 wt.%.

In a preferred embodiment, the one or more surfactants are selected from the group consisting of anionic surfactants, non-ionic surfactants, cationic surfactants, amphoteric surfactants, zwitterionic surfactants, and combinations thereof; preferably the one or more surfactants are selected from the group consisting of non-ionic surfactants, anionic surfactants and combinations thereof.

In a preferred embodiment, the composition is a liquid composition, preferably comprising between 10 wt.% and 90 wt.% of water, based on the total weight of the composition, preferably between 30 wt.% and 90 wt.%, more preferably between 50 wt.% and 90 wt.%, even more preferably between 60 wt.% and 85 wt.%, most preferably between 65 wt.% and 80 wt.%.

In an embodiment, the pH at 20°C of the composition is between 2.5 and 6.5, preferably between 3 and 6, more preferably between 4 and 5.

In an embodiment, the composition has a viscosity measured at 20°C and 10 rpm of between 50 mPa s and 50000 mPa s, preferably between 100 mPa s and 10000 mPa s, more preferably between 250 mPa s and 5 000 mPa s, even more preferably between 500 mPa s and 2500 mPa s.

In a preferred embodiment, the composition is a laundry additive composition.

In a second aspect, the invention relates to a method of washing a garment, comprising:

- washing a garment with the laundry composition according to the first aspect of the invention; or

- washing a garment with a mixture comprising a laundry detergent composition and the laundry composition according to the first aspect of the invention; or adding a laundry composition according to the first aspect of the invention to water in a receptacle and soaking for a predetermined length of time; or a) pre-treating the garment with the laundry composition according to the first aspect of the invention; and b) washing the pre-treated garment of step a) with the laundry composition according to the first aspect of the invention, or a laundry detergent composition, or with a mixture comprising a laundry detergent composition and the laundry composition according to the first aspect of the invention wherein the method is performed at a temperature lower than 50°C, preferably lower than 40°C, more preferably at a temperature between 10°C and 35°C, even more preferably between 15°C and 30°C, most preferably between 20°C and 30°C.

In a third aspect, the invention relates to a use of the laundry composition according to the first aspect of the invention for the removal of stains from a garment, and preferably for the reduction or inhibition of malodour in a garment. Definitions

The following definitions are used in the present application.

“Laundry composition” as used in the present application means: compositions which can be used for pre-treating a garment before washing the garment with a laundry detergent, and/or that can be used alone for washing a garment, and/or that can be used together with the laundry detergent during washing of the garment, and/or that can be used as a rinse cycle composition. In other words, the laundry composition can be used alone for washing a garment or can be used as an auxiliary of the laundry detergent. A laundry composition includes, but is not limited to, products for the care of garments, removal of stains, cleaning of garments, sanitisation of garments, disinfecting of garments, stain removers.

“Laundry detergent composition” as used in the present application means: composition used solely for the cleaning of garments and whose main action is the removal of grime and dirt.

“Laundry additive composition” as used in the present application means: composition which is used for providing a specific consumer benefit, such as, removal of stains, reduction or inhibition of dye transfer, elimination of malodour, improvement of whiteness and/or disinfection of garments. This means that the mean action of a laundry additive is not the removal or grime and dirt. Furthermore, a laundry additive is commonly used as a pre-treatment, in soaking conditions or together with a laundry detergent composition.

Detailed description of the invention

In a first aspect, the present invention relates to a laundry composition comprising an oxygen-based bleach and a dye transfer inhibitor system comprising a homopolymer of

1-vinyl-2-pyrrolidone (PVP) and an alkali metal salt of poly (N-carboxymethyl-4- vinylpyridinium) chloride.

The present inventors have observed a surprising synergistic effect between an oxygenbased bleach and a dye transfer inhibitor system comprising a homopolymer of 1-vinyl-

2-pyrrolidone (PVP) and an alkali metal salt of poly (N-carboxymethyl-4- vinylpyridinium) chloride. This synergy is shown by the stain removal properties of the composition according to the invention, in particular the removal of bleachable stains such as curry, grass, or tea. This is surprising as stain removal of bleachable stains would be expected by adding enzymes or dramatically increasing the bleach content of the composition, but not by combining the two dye transfer inhibitors and the oxygen-based bleach.

The person skilled in the art will recognise that PVP and the alkali metal salts of poly (N- carboxymethyl-4- vinylpyridinium) chloride are normally used as dye transfer inhibitors; however, it is surprising that they have a synergy with the oxygen-based bleach as shown in the present disclosure.

Without wishing to be bound by any theory, the present inventors believe that the PVP and the alkali metal salts of poly (N-carboxymethyl-4- vinylpyridinium) chloride in the composition help solubilising different compounds, aiding in this manner with the removal of stains, in particular, bleachable stains.

In addition, the present inventors have observed that the combination of the dye transfer inhibitor system with the oxygen-based bleach provides reduction or inhibition of malodour in a garment.

Oxygen-based bleach

The oxygen-based bleach may be hydrogen peroxide or a precursor of hydrogen peroxide, preferably the oxygen-based bleach is hydrogen peroxide.

Due to the lack of stability of liquid peroxide, because of its high reactivity, in combination with other detergent ingredients, oxygen bleach precursors are commonly used in the detergent industry. These are broken down in situ to release hydrogen peroxide.

The most common bleach precursor is sodium percarbonate. This is solid and, if kept dry, fairly stable allowing it to be mixed with a wide variety of common detergent composition components. The majority of detergents using oxygen bleach cleaning utilise sodium percarbonate as a source of oxygen bleach.

Despite its effectiveness, sodium percarbonate still has drawbacks. The percarbonate needs to break down to release the peroxide and this is a highly temperature-dependent reaction. With household energy use (due to a desire to limit damage to the environment) being an increasingly important concern, reduced washing temperatures are offered on all new domestic cleaning machines. Where once 60°C washing was standard, now 30- 40°C cleaning temperatures are encouraged. The reduced temperatures make the breakdown of the percarbonate happen much more slowly, reducing the effectiveness of the bleaching. Catalysts can be added to the detergent compositions to assist this process at lower temperatures, but they are an additional cost and waste.

Therefore, the specially preferred oxygen-based bleach is hydrogen peroxide.

The laundry composition may comprise between 1 wt.% and 15 wt.% of the oxygenbased bleach, based on the total weight of the composition, preferably between 2 wt.% and 14 wt.% more preferably between 3 wt.% and 13 wt.%, even more preferably between 4 wt.% and 12 wt.%, most preferably between 5 wt.% and 11 wt.%.

Dye transfer inhibitor system

In an embodiment, the homopolymer of 1-vinyl-2-pyrrolidone (PVP) has a molecular weight of between 10 000 g/mol and 200 000 g/mol, preferably between 20 000 g/mol and 100000 g/mol, more preferably between 30000 g/mol and 50 000 g/mol, even more preferably between 35 000 g/mol and 45 000 g/mol. A preferred example of PVP is Sokalan ® HP53 ex. BASF, which is a suspension with approximately 30% of a PVP having a molecular weight of about 40 000 g/mol.

As used herein the term molecular weight refers to the weight average molecular weight.

In an embodiment, the alkali salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride is a sodium salt. A preferred example of a sodium salt of poly (N-carboxymethyl-4- vinylpyridinium) chloride is Chromabond ^TM S-100 polymer ex. Ashland, which is an aqueous solution having 40% of the polymer and which chemically can be represented by the following formula:

The composition according to the invention comprises a dye transfer inhibitor system comprising a homopolymer of 1-vinyl-2-pyrrolidone (PVP) and an alkali metal salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride. The composition may comprise between 0.01 wt.% and 10 wt.% of the dye transfer inhibitor system, based on the total weight of the composition, preferably between 0.05 wt.% and 7.5 wt.%, more preferably between 0.1 wt.% and 5 wt.%, even more preferably between 0.2 wt.% and 2.5 wt.%.

The present inventors have also observed that the weight ratio between the homopolymer of 1-vinyl-2-pyrrolidone (PVP) and the alkali metal salt of poly (N- carboxymethyl-4-vinylpyridinium) chloride might affect the stain removal properties of the composition comprising an oxygen-based bleach. Therefore, in an embodiment, the weight ratio between the homopolymer of 1-vinyl-2-pyrrolidone (PVP) and the alkali metal salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride is between 0.01 :1 and 2:1 , preferably between 0.05:1 and 1 :1 , more preferably between 0.1 :1 and 0.8:1 , even more preferably between 0.15:1 and 0.75:1 , most preferably between 0.2:1 and 0.7:1.

The composition may further comprise one or more dye transfer inhibitors selected from the group comprising polyvinylalcohol, fatty amides, sodium carboxylmethyl cellulose, hydroxypropyl methyl cellulose, polyvinylimidazole, polyvinyloxazolidone, polyamine N- oxide polymers, copolymers of 1-vinyl-2-pyrrolidone and 1-vinylimidazole (PVP-VI), and combinations thereof.

In a preferred embodiment, the composition further comprises a dye transfer inhibitor being 2-Propenoic acid, 2-methyl-, 2-(dimethylamino) ethyl ester, polymer with 1- ethenyl-2-pyrrolidinone. An example of this dye transfer inhibitor is Sorez ^TM ex. Ashland.

Surfactants

The composition may comprise one or more surfactants. The one or more surfactants may be selected from the group consisting of anionic surfactants, non-ionic surfactants, cationic surfactants, amphoteric surfactants, zwitterionic surfactants, and combinations thereof; preferably the one or more surfactants are selected from the group consisting of non-ionic surfactants, anionic surfactants and combinations thereof. Many such suitable surfactants are described in Kirk Othmer's Encyclopedia of Chemical Technology, 3rd Ed., Vol. 22, pp. 360-379, "Surfactants and Detersive Systems".

The composition may comprise between 0.5 wt.% and 70 wt.% of one or more surfactants, based on the total weight of the composition, preferably between 1 wt.% and 50 wt.%, more preferably between 2.5 wt.% and 40 wt.%, even more preferably between

5 wt.% and 30 wt.%, most preferably between 10 wt.% and 20 wt.%.

For example, the surfactant may comprise one or more non-ionic surfactants, preferably ethoxylated alcohols and ethoxylated alkyl phenols having the formula R¹(OCH2CH2)nOH; wherein R¹ is an aliphatic hydrocarbon radicals containing between 10 and 24 carbon atoms or alkyl phenyl radicals in which the alkyl groups contain from 10 to 22 carbon atoms; and n has an average value of from 1 to 10.

The surfactant may comprise any conventional anionic surfactant or a mixture of them used in detergent products. These include, for example, the alkyl benzene sulfonic acids and their salts as well as alkoxylated or non-alkoxylated alkyl sulfate materials. The anionic surfactants may be present in acid form or in neutralized (e.g., salt) form. The anionic surfactants may be linear, branched, or a mixture thereof. An example of an anionic surfactant is sodium cumenesulphonate.

Examples of anionic surfactants are the alkali metal salts of C10-16 alkyl benzene sulphonic acids or Cn-14 alkyl benzene sulphonic acids.

Another exemplary type of anionic surfactant is alkoxylated alkyl sulphate surfactants, such as ethoxylated alkyl sulphate surfactants. Such materials are also known as alkyl ether sulphates or alkyl polyethoxylate sulphates.

Alkyl ether sulphates are generally available in the form of mixtures comprising varying R' chain lengths and varying degrees of ethoxylation. Frequently such mixtures also contain some non- ethoxylated alkyl sulphate ("AS") materials.

Softening agents

The composition may comprise one or more softening agents. Exemplary softening agents are organic water-soluble water softening agents, which include polycarboxylate polymers, such as polyacrylates, acrylic/maleic copolymers, and acrylic phosphonates, monomeric polycarboxylates such as citrates, gluconates, oxydisuccinates, glycerol mono- di- and trisuccinates, carboxymethyloxysuccinates, carboxymethyloxymalonates, dipicolinates, hydroxyethyliminodiacetates, phosphonates, iminodisuccinates, polyaspartic acids, butylated hydroxytoluene (BHT), phosphonate stabilisers such as, diethylenetriaminepenta (methylene phosphonic acid and its corresponding pentasodium salt), DTP MP and DTPMA and hydroxy ethylidene diphosphonic acid (HEDP). Further exemplary water-soluble water softening agents are neutralised or partially neutralised carboxylic acids, such as citric acid, succinic acid or maleic acid, and/or a neutralised or partially neutralised polycarboxylic acid, such as a polyacrylate of Mw: 4000-8000.

It should be noted that some substances may have several functions in the formulation. For example, HEDP is a chelating agent and it helps in stabilising the hydrogen peroxide in the formulation. Another example is triethanolamine, which is a polar organic solvent, but in the present application it is considered an additive and not a polar organic solvent.

Optical brightener

The composition may comprise an optical brightener, preferably selected from the group comprising stilbene, benzidine, benzothiazole, benzimidazole, benzoxazole, coumarin, pyrazoline, naphthalimide, naphthoxazole, distyryl-biphenyl, benzonitrile, benzopyrazole, including their derivatives and substituted compounds, and combinations thereof. Suitable optical brighteners include 4,4’-bis(2-sulphostyryl)diphenyl, 7- Diethylamino-4-methylcoumarin, benzoxazole, 2,2'-(1 ,2-ethenediyl) bis[5-methyl] including their substituted compounds, 4,4'-bis (triazine-2-ylamino) stilbene-2,2'- disulphonic acid, mono (azol-2-yl) stilbene and bis (azol-2yl) stilbene; styryl derivatives of benzene and biphenyl, such as 1 ,4-bis (styryl) benzene, 4,4'-bis (styryl) benzene, 4,4'- bis- (styryl) biphenyl, 4,4'-bis (sulphostryryl) biphenyl sodium salt; pyrazolines such as 1 , 3-diphenyl-2-pyrazoline; bis (benzene-2-yl) derivatives, bis (benzoxazol-2-yl) derivatives and bis (benzimidazol-2-yl) derivatives; 2- (benzofuran-2-yl) benzimidazole; coumarins such as 4-methyl-7-hydroxy-coumarin or4-methyl-7-diethylaminocoumarin; carbostyrils; naphthalimides; dibenzothiophene5,5-dioxide; pyrene; or pyridotriazole derivatives and combinations thereof.

When an optical brightener is present, the composition may comprise between 0.001 wt.% and 1 wt.% of at least one optical brightener, based on the total weight of the composition, preferably between 0.01 wt.% and 0.5 wt.%, more preferably between 0.05 wt.% and 0.25 wt.%. pH modifier

The compositions according to the invention may also comprise a pH modifier, i.e. a source of acidity or a source of alkalinity, to obtain the desired pH, on dissolution. A source of acidity may be any suitable acidic compound for example a polycarboxylic acid. For example, a source of alkalinity may be a carbonate or bicarbonate (such as the alkali metal or alkaline earth metal salts). A source of alkalinity may be any suitable basic compound for example any salt of a strong base and a weak acid. When an alkaline composition is desired silicates are amongst the suitable sources of alkalinity. Materials commonly used as a source of alkalinity are NaOH (sodium hydroxide), and tri- di - or monoethanolamine; while sulfuric acid is commonly used as a source of acidity. Conventional amounts of the alkalinity or acidity source may be used.

For example, the laundry compositions according to the invention may comprise between 0.05 wt.% and 10 wt.% of a pH modifier, for example between 0.1 wt.% and 5 wt.%, based on the total weight of the formulation.

The pH of the laundry composition is, for example, between 2.5 and 6.5, preferably between 3 and 6, more preferably between 4 and 5.

In an embodiment, the laundry composition is a liquid composition. It should be understood that a liquid, as used in the present disclosure, includes not only a conventional liquid, but also emulsions, gels, suspensions, viscous liquids which are materials that free flow when a force is applied. The laundry composition may comprise between 10 wt.% and 90 wt.% of water, based on the total weight of the composition, preferably between 30 wt.% and 90 wt.%, more preferably between 50 wt.% and 90 wt.%, even more preferably between 60 wt.% and 85 wt.%, most preferably between 65 wt.% and 80 wt.%.

The composition may have a viscosity measured at 20°C and 10 rpm of between 50 mPa s and 50 000 mPa s, preferably between 100 mPa s and 10 000 mPa s, more preferably between 250 mPa s and 5 000 mPa s, even more preferably between 500 mPa s and 2500 mPa s; for example between 750 mPa s and 2500 mPa s. Therefore, the term liquid as used in the present disclosure does not encompass selfstanding gels, which are considered solids instead.

In an embodiment the composition is a laundry additive composition.

The composition may include one or more additional ingredients selected from the group consisting of chelating agents, organic solvents, anti-fading agents, anti-bacterial agents, preservatives, fabric softeners, anti-static agents, fragrances, odor absorbing components, thickeners, and dyes.

The garment may be made of a wide range of materials, such as cotton, linen, and synthetic materials.

A garment may be washed by adding certain amount; e.g. 100 mL, of the laundry composition according to the first aspect of the invention to a washing machine and washing the garment following a regular cycle of said machine. In a preferred embodiment, a garment is washed with a mixture comprising a laundry detergent composition and between 10 mL and 500 mL of the laundry composition according to the first aspect, preferably between 20 mL and 250 mL, more preferably between 50 mL and 200 mL, even more preferably between 80 mL and 150 mL. This mixture may be added to a washing machine and the garment may be then washed following a regular cycle of said machine. The proportion in weight of regular detergent composition to the laundry composition according to the invention in the mixture may be (weight of detergent composition : weight of composition according to the invention) at least 1 :1 , preferably at least 1 :1.5, more preferably at least 1 :2, even more preferably at least 1 :2.5, most preferably at least 1 :5. In other words, the amount of the composition according to the invention in the mixture may be the same or higher than the amount of the detergent composition.

A garment may be also washed by firstly pre-treating the garment with the composition according to the first aspect of the invention and then washing the pre-treated garment using a regular cycle of a washing machine to which, the composition according to the invention, or a regular laundry detergent composition or a mixture comprising a laundry detergent composition and the laundry composition according to the invention has been added. Said pre-treatment comprises for example applying an effective amount of the composition according to the first aspect to a stain on the garment, allowing the composition to act for certain amount of time, for example 1 to 45 minutes, preferably 10 minutes, and rubbing it against itself.

In a third aspect, the invention relates to a use of the laundry composition according to the first aspect of the invention for the removal of stains from a garment and preferably for the reduction or inhibition of malodour in garment.

In an embodiment, the stains comprise a polyphenolic compound, preferably the stains comprise turmeric and/or curry stains.

The garment may be made of cotton, synthetic materials or a combination thereof.

In a further aspect, the invention relates to the use of the composition according to the first aspect of the invention for the reduction or elimination of bacteria, germs, viruses and/or fungi from a garment. The foregoing aspects may be freely combined with any of the foregoing aspects disclosed herein.

The invention will be further described, by way of example, with the reference to the following non-limiting embodiments.

Examples

Formulations

Table 1 shows: comparative composition (composition A) in which the dye transfer inhibitor system only contains a homopolymer of 1-vinyl-2-pyrrolidone (PVP), and a composition according to the invention (composition 1), in which the dye transfer inhibitor system contains a homopolymer of 1-vinyl-2-pyrrolidone (PVP) and a sodium salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride.

The compositions were prepared by mixing the different ingredients to obtain a liquid composition with a pH of between 4 and 5, for example, 4.3; and a viscosity of between 1500 - 2000 mPa s measured at 20°C using a viscosimeter Brookfield RV, spindle S27, at 10 rpm.

Table 1. Laundry compositions

In Table 1 :

• Non-ionic surfactant: ethoxylated alcohols with an ethoxylation degree between 2 and 8.

• Anionic surfactant: Alkyl benzene sulphonic acid, alkyl ether sulphate.

• PVP: the homopolymer of 1 -vinyl-2-pyrrolidone with a molecular weight of 40000 g/mol.

• Sodium salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride is Chromabond T^M S-100 polymer ex. Ashland

• Quantities of the ingredients are given in % of active substance. For example, the PVP is Sokalan ® HP 53 ex. BASF, having a concentration of 30% active substance. The amount of Sokalan HP 53 in Composition A is 0.43 wt.%, which corresponds to 0.129 wt.% of PVP.

Performance tests

Stain removal - laundry washing machine

The stain removal performance of different detergent systems was tested using standard soils.

Washing conditions

The standard soils were washed at 30 °C using water with a hardness of 28 °f and one of the detergent systems shown in Table 2 in a laundry washing machine with the following specifications:

• Washing machine: Miele WDB020.

• Wash cycle: cotton, water in main wash: 17 L ± 2 L, time of main wash: 52 min ± 5 min.

• Load: 3.5 Kg of clean, white cotton ballast.

After washing, the test swatches were dried in a tumble dryer and ironed with a domestic iron.

Table 2 shows the different detergent systems that were added to the washing machine.

Table 2. Detergent systems

n table 2, the commercial detergent is Ariel liquid as sold in the UK. This commercial detergent does not contain any oxygen-based bleach or any dye transfer inhibitor. Stain removal

Stain removal was determined using a Datacolor spectrophotometer 650 and by measuring the Y-value of the standard soil after washing. A higher Y-value represents a better stain removal. Table 3. Removal of enzymatic, bleachable and greasy stains.

From table 3, it is clear that the laundry composition according to the invention, in particular in combination with a laundry detergent composition, provides stain removal, in particular, removal of bleachable stains.

In addition, the stain removal experiments were statistically analysed, and the performance of the detergent system 1 (Ds 1) was compared with the performance of detergent system A (Ds A). This comparison in shown in table 4, in which:

• P (Parity), means that the stain removal performance of Ds 1 was the same as that of Ds A. • S (Superior), means that the stain removal performance of Ds 1 was superior than that of Ds A.

Table 4. Comparison of stain removal performance.

The results in table 4 show that the laundry composition according to the invention provides better stain removal performance than the comparative laundry composition, in particular when considering the removal of bleachable stains. Therefore, the synergy between the homopolymer of 1-vinyl-2-pyrrolidone (PVP) and the alkali metal salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride is demonstrated.

Hence one or more objects of the present invention are achieved by the present which is further elucidated in the appended claims.

Claims

1. A laundry composition comprising an oxygen-based bleach and a dye transfer inhibitor system comprising a homopolymer of 1-vinyl-2-pyrrolidone (PVP) and an alkali metal salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride.

2. Laundry composition according to claim 1 , wherein the homopolymer of 1-vinyl- 2-pyrrolidone (PVP) has a molecular weight of between 10 000 g/mol and 200000 g/mol, preferably between 20 000 g/mol and 100 000 g/mol, more preferably between 30 000 g/mol and 50 000 g/mol, even more preferably between 35 000 g/mol and 45 000 g/mol.

3. Laundry composition according to claim 1 or claim 2, wherein the alkali salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride is a sodium salt.

4. Laundry composition according to any of the preceding claims, wherein the composition comprises between 1 wt.% and 15 wt.% of the oxygen-based bleach, based on the total weight of the composition, preferably between 2 wt.% and 14 wt.% more preferably between 3 wt.% and 13 wt.%, even more preferably between 4 wt.% and 12 wt.%, most preferably between 5 wt.% and 11 wt.%.

5. Laundry composition according to any of the preceding claims, wherein the oxygen-based bleach is hydrogen peroxide or a precursor of hydrogen peroxide, preferably the oxygen-based bleach is hydrogen peroxide.

6. Laundry composition according to any of the preceding claims, wherein the composition comprises between 0.01 wt.% and 10 wt.% of the dye transfer inhibitor system, based on the total weight of the composition, preferably between 0.05 wt.% and 7.5 wt.%, more preferably between 0.1 wt.% and 5 wt.%, even more preferably between 0.2 wt.% and 2.5 wt.%.

7. Laundry composition according to any of the preceding claims, wherein the weight ratio between the homopolymer of 1-vinyl-2-pyrrolidone (PVP) and the alkali metal salt of poly (N-carboxymethyl-4-vinylpyridinium) chloride is between 0.01 :1 and 2:1 , preferably between 0.05:1 and 1 :1 , more preferably between 0.1 :1 and 0.8:1 , even more preferably between 0.15:1 and 0.75:1 , most preferably between 0.2:1 and 0.7:1.

8 Laundry composition according to any of the preceding claims, wherein the composition further comprises between 0.5 wt.% and 70 wt.% of one or more surfactants, based on the total weight of the composition, preferably between 1 wt.% and 50 wt.%, more preferably between 2.5 wt.% and 40 wt.%, even more preferably between 5 wt.% and 30 wt.%, most preferably between 10 wt.% and 20 wt.%.

9. Laundry composition according to claim 8, wherein the one or more surfactants are selected from the group consisting of anionic surfactants, non-ionic surfactants, cationic surfactants, amphoteric surfactants, zwitterionic surfactants, and combinations thereof; preferably the one or more surfactants are selected from the group consisting of non-ionic surfactants, anionic surfactants and combinations thereof.

10. Laundry composition according to any of the preceding claims, wherein the composition is a liquid composition, preferably comprising between 10 wt.% and 90 wt.% of water, based on the total weight of the composition, preferably between 30 wt.% and 90 wt.%, more preferably between 50 wt.% and 90 wt.%, even more preferably between 60 wt.% and 85 wt.%, most preferably between 65 wt.% and 80 wt.%.

11. Laundry composition according to claim 10, wherein the pH at 20°C of the composition is between 2.5 and 6.5, preferably between 3 and 6, more preferably between 4 and 5.

12. Laundry composition according to claim 10 or 11 , wherein the composition has a viscosity measured at 20°C and 10 rpm of between 50 mPa s and 50 000 mPa s, preferably between 100 mPa s and 10 000 mPa s, more preferably between 250 mPa s and 5 000 mPa s, even more preferably between 500 mPa s and 2500 mPa s.

13. Laundry composition according to any of the preceding claims, wherein the composition is a laundry additive composition.

14. Method of washing a garment, comprising:

- washing a garment with the laundry composition according to any of the claims 1-13; or

- washing a garment with a mixture comprising a laundry detergent composition and the laundry composition according to any of the claims 1-13; or adding a laundry composition according to any of the claims 1-13 to water in a receptacle and soaking for a predetermined length of time; or a) pre-treating the garment with the laundry composition according to any of the claims 1-13; and b) washing the pre-treated garment of step a) with the laundry composition according to any of the claims 1-13, or a laundry detergent composition, or with a mixture comprising a laundry detergent composition and the laundry composition according to any of the claims 1-13 wherein the method is performed at a temperature lower than 50°C, preferably lower than 40°C, more preferably at a temperature between 10°C and 35°C, even more preferably between 15°C and 30°C, most preferably between 20°C and 30°C.

15. Use of the laundry composition according to any of the claims 1-13 for the removal of stains from a garment, and preferably for the reduction or inhibition of malodour in a garment.