Technical field of the invention

The present invention relates to a peroxide-containing cleaning system for removing stains from substrates, such as fabrics. The cleaning system comprises a spraying device that holds a foamable liquid cleaning composition, said foamable liquid cleaning composition comprising:

a) 1 to 20 wt.% of alkoxylated Ce-ie alkyl ether sulfate surfactant having 1 to 30 moles of alkylene oxide;

b) 0.1 to 3 wt.% of amphoteric surfactant;

c) 2 to 12 wt.% of hydrogen peroxide;

d) at least 65 wt.% water. This cleaning system can suitably be used to apply the liquid cleaning composition as a foam onto e.g. stained fabric.

The invention further relates to a method of removing stains from fabric, said method comprising the steps of

a) providing a fabric;

b) pre-treating the fabric by applying a liquid cleaning composition as defined in any one of the preceding claims as a foam onto the surface of the fabric;

c) washing the pre-treated fabric; and

d) drying the washed fabric.

Background of the invention

Removal of stains from fabric can be a challenge. Washing stained fabric with a detergent may produce a satisfactory result if the stains are light and not greasy. However, if the stains are heavy, washing with detergent often does not remove the stains because the detergent ingredients are diluted in the wash and are not concentrated at the stain.

To successfully remove heavy stains, it is known in the art to apply a separate stain treatment, e.g., by spraying or squirting a stain treatment product directly on the stain or using a wipe impregnated with a stain treatment product to scrub a stain. US2012/0324653 AA (P&G) describes a product for pre-treatment and laundering of fabric having a stained portion, said product comprising:

• a pourable aqueous detergent composition comprising: a) a hydrophobic surfactant system having a Hydrophilic Index of from about 6 to about 9

· a cap for dispensing said pourable aqueous detergent composition.

WO96/30474 A1 (P&G) describes a method of pretreating fabrics with a composition comprising

amine oxide surfactant, said method comprising the steps of applying said composition in its neat form onto the fabric, and allowing said composition to remain in contact with said fabric before said fabric is washed.

Cleaning systems comprising a spraying bottle and a foaming cleaning system have also been described in the prior art.

JP2009108208 A2 (Lion Corp) describes a cleaner composition for wiping in a foam. The cleaner composition for wiping is stored in a trigger sprayer having a foam forming mechanism and is used, wherein the composition contains 0.1 -5.0 mass percent of hydrogen peroxide (A) and 0.2-3.5 mass percent of at least one (B) selected from a linear alkylbenzenesulfonic acid or a salt thereof, an alkanesulfonic acid or a salt thereof and a polyoxyethylene alkyl ether sulfuric acid ester or a salt thereof as anionic surfactants and an amphoteric surfactant and has a viscosity at 25 degrees centigrade of <10 mPa.s.

US201 1/0180619 AA (Dial Corp) describes a foaming hypochlorite cleaning system comprising:

a) a composition comprising:

i. a disulfonate surfactant;

ii. an alkyl sulfate surfactant;

iii. alkali metal or alkaline earth hypo chlorite; and

iv. water;

b) a bottle comprising a body with a relatively flat bottom and an angled-neck with an opening, said bottle having the composition within; and

c) an invertible trigger sprayer assembly fastened to said opening of said bottle, said sprayer comprising a dip tube, trigger lever and nozzle, said sprayer manually operable to expel said composition in a general direction from said nozzle. Aqueous liquid detergent compositions containing peroxide bleach, alkyl ether sulphate surfactant and amphoteric surfactant have been described in some prior art publications.

US201 1/0071334 AA (Commissariat A L Energie Atomique Et Aux Energies Alternatives) describes a foaming decontaminating aqueous solution, characterized in that it comprises, by weight relative to the total weight of the composition:

• 0.1 % to 20% of an organic or mineral water-soluble peroxidizing agent;

• 0.05% to 20% of an anionic surfactant;

• 0.1 % to 20% of an amine oxide;

· 0 to 5% of a stabilizer for the peroxidizing agent;

• 0 to 10% of an amphoteric surfactant;

• 0 to 15% of an alkaline buffer; and

• the remainder to 100% being water.

The foaming decontaminating aqueous solution can be used for dismantling explosive devices and decontaminating the toxic and/or bacteriological agents contained therein.

EP0667392 A2 (Jeyes Corp PLC, 1995) describes a thickened alkaline peroxide bleaching composition comprising:

• hydrogen peroxide;

· water;

• a stabiliser for the hydrogen peroxide;

• a water-soluble electrolyte; and

• a surfactant/thickening component comprising (i) an alkyl ether sulphate surfactant together with an amine oxide or betaine surfactant and, optionally, an alkane sulphonate surfactant; or (ii) an amine oxide surfactant together with a sarcosinate surfactant and, optionally, an alkane sulphonate surfactant.

WO96/30456 A1 (P&G) describes a liquid bleaching composition comprising hydrogen peroxide or a source thereof and a liquid hydrophobic bleach activator, said composition being formulated as a microemulsion of said hydrophobic liquid bleach activator in a matrix comprising water, said hydrogen peroxide or source thereof and a hydrophilic surfactant system comprising an anionic and a nonionic surfactant.

WOOO/04121 A1 (Reckitt Benckiser LLC) describes an aqueous cleaning and surface treatment composition adapted for cleaning of fibers and fibrous substrates comprising: • an oxidizing agent ;

• an anionic surfactant, preferably one or more alkyl sulfates or salts thereof ;

• an amine oxide surfactant;

• one or more organic solvents,

· an antiresoiling compound; and

• water.

Summary of the invention

The present invention provides a cleaning system that can suitably be applied for removal of various types of stains from fabric.

More specifically, the present invention provides a cleaning system comprising a spraying device and a foamable liquid cleaning composition, said spraying device comprising a container holding the foamable liquid cleaning composition, a spray head, and a liquid supply arrangement for transferring the foamable liquid detergent composition from the container to the spray head, said foamable liquid cleaning composition comprising:

a) 1 to 20 wt.% of alkoxylated Ce-ie alkyl ether sulfate surfactant having 1 to 30 moles of alkylene oxide;

b) 0.1 to 3 wt.% of amphoteric surfactant;

c) 2 to 12 wt.% of hydrogen peroxide;

d) at least 65 wt.% water;

said cleaning composition having a viscosity of less than 100 mPa.s at 25°C and 20 s ^"1 , and forming a foam with a density of less than 0.4 g/ml when ejected from the spray device through the spray head wherein the cleaning composition contains the alkoxylated Ce-ie alkyl ether sulfate surfactant and the amphoteric surfactant in a weight ratio of 1 :1 to 200:1.

The cleaning system of the present invention can be used to deliver the cleaning composition in the form of a foam, which enables targeting the cleaning composition on the stain at significantly lower dosages and with less spreading, whilst maintaining cleaning performance. The cleaning compositions contains a surfactant combination that aids both stain removal and the formation of a stable foam. In addition, the cleaning composition contains a hydrogen peroxide. The cleaning composition is particularly effective at removing bleachable stains because of the high oxygen availability within the foam structure.

The present invention further provides a method of removing stains from fabric, said method comprising the steps of

a) providing a fabric;

b) pre-treating the fabric by applying a liquid cleaning composition of the present invention as a foam onto the surface of the fabric;

c) washing the pre-treated fabric; and

d) drying the washed fabric.

Also provided by the present invention is the use of the liquid cleaning composition of the present invention for the removal of stains from fabric, said use comprising applying the liquid cleaning composition in the form of a foam onto the surface of the fabric.

Detailed description of the invention

Accordingly, a first aspect of the present invention relates to a cleaning system comprising a spraying device and a foamable liquid cleaning composition, said spraying device comprising a container holding the foamable liquid cleaning composition, a spray head, and a liquid supply arrangement for transferring liquid detergent composition from the container to the spray head, said foamable liquid cleaning composition comprising: a) 1 to 20 wt.% of alkoxylated Ce-ie alkyl ether sulfate surfactant having 1 to 30 moles of alkylene oxide;

b) 0.1 to 3 wt.% of amphoteric surfactant;

c) 2 to 12 wt.% of hydrogen peroxide;

d) at least 65 wt.% water;

said cleaning composition having a viscosity of less than 100 mPa.s at 25°C and 20 s ^"1 , and forming a foam with a density of less than 0.4 g/ml when ejected from the spray device through the spray head wherein the cleaning composition contains the alkoxylated Ce-ie alkyl ether sulfate surfactant and the amphoteric surfactant in a weight ratio of 1 :1 to 200:1.

The viscosity of the liquid cleaning composition can be determined using a AR 1000 Rheometer using a 4 cm flat plate spindle. Foamable liquid cleaning composition

The liquid cleaning composition of the present invention contains the alkoxylated Ce-ie alkyl ether sulfate surfactant and the amphoteric surfactant in a weight ratio of 1 :1 to 200:1 , more preferably 2:1 to 200:1 , more preferably in a weight ratio of 4:1 to 120:1 and most preferably of 6:1 to 100:1 .

The combination of the alkoxylated Ce-ie alkyl ether sulfate surfactant and the amphoteric surfactant typically constitutes 1.5 to 21 wt.%, more preferably 1.8 to 19 wt.% and most preferably 2.1 to 13 wt.% of the foamable liquid cleaning composition.

The foamable liquid cleaning composition of the present invention typically has a viscosity of less than 75 mPa.s, more preferably of less than 50 mPa.s, most preferably less than 40 mPa.s at 25°C and 20 s ^"1 .

The pH of the foamable liquid cleaning composition preferably lies in the range of 2 to 7. More preferably, the pH of the cleaning composition is in the range of 2.2 to 6, even more preferably in the range of 2.4 to 5. Most preferably, the pH is in the range of 2.5 to 4.

The liquid cleaning composition preferably forms a foam with a density of less than 0.35 g/ml, more preferably of 0.3 to 0.1 g/ml when ejected from the spray device through the spray head. The foam produced by ejecting the liquid cleaning composition from the spraying device typically retains a density of less than 0.4 g/ml, more preferably of less than 0.3 g/ml during at least 5 minutes at atmospheric pressure and a temperature of 25°C.

Spraying device

The spraying device of the present invention preferably comprises a container having an internal volume of 100 to 1 ,500 ml, more preferably of 150 to 1 ,200 ml, even more preferably 180 to 1000 ml and most preferably of 200 to 800 ml.

The spraying device preferably comprises a positive displacement pump that acts directly on the liquid cleaning composition. The pump draws the liquid cleaning composition up into the liquid supply arrangement and transfers the liquid detergent composition to the spray head, from which it is discharged in the form of a foam, preferably through a nozzle. In the spraying device of the present invention, the dispensing of the liquid cleaning composition is preferably powered by a user's efforts, i.e. the liquid cleaning composition is not dispensed under pressure by simply actuating a valve.

The spraying device employed in accordance with the present invention is preferably selected from a trigger spray foam bottle, a squeeze foam bottle and a foam pump. Most preferably the spraying device is a squeeze foam bottle or a foam pump.

In another preferred embodiment, the spray device is configured to mix the liquid cleaning composition with air before it is dispensed from the spray head.

Alkoxylated alkyl ether sulfate

The liquid cleaning composition of the present invention preferably contains 2 to 16 wt.% of ethoxylated Ce-ie alkyl ether sulfate surfactant having 1 to 30 moles of ethylene oxide.

Even more preferably, the liquid cleaning composition contains preferably 2 to 16 wt.% of ethoxylated Ce-ie alkyl ether sulfate surfactant having 1 to 20 moles of ethylene oxide. According to a particularly preferred embodiment, the cleaning system contains preferably 2 to 16 wt.% of ethoxylated C10-14 alkyl ether sulfate surfactant having 1 to 30 moles of ethylene oxide. Yet more preferably, the composition contains preferably 2 to 16 wt.% of ethoxylated C10-14 alkyl ether sulfate surfactant having 1 to 20 moles of ethylene oxide. Yet even more preferably, the composition contains preferably 2 to 16 wt.% of ethoxylated C10-14 alkyl ether sulfate surfactant having 1 to 10 moles of ethylene oxide.

According to a particularly preferred embodiment, the liquid cleaning composition contains preferably 1 .5 to 16 wt.%, most preferably 2 to 10 wt.% of ethoxylated lauryl ether sulfate surfactant having 1 to 10 moles of ethylene oxide. Amphoteric surfactant

The amphoteric surfactant that is employed in accordance with the present invention may be selected from amine oxide, betaine and/or combinations thereof.

Preferably, the cleaning composition contains at least 0.1 wt.%, more preferably 0.2 to 3 wt.%, even more preferably 0.5 to 2.5 wt.% and most preferably 0.8 to 2 wt.% of amine oxide, betaine or combinations thereof. A preferred amine oxide is C12-16 alkyl dimethyl amine oxide. A preferred betaine is cocamidopropyl betaine.

More preferably, the cleaning composition contains at least 0.1 wt.%, preferably 0.2 to 3 wt.% of amine oxide.

According to a particularly preferred embodiment, the cleaning composition contains at least 0.1 wt.% , preferably 0.2 to 3 wt.% of C12-16 alkyl dimethyl amine oxide.

Non-ionic surfactant

In a preferred embodiment, the cleaning composition of the present invention further contains 2 to 16 wt.% of a non-ionic surfactant, more preferably 3 to 13 wt.% and most preferably 4 to 10 wt.% of a non-ionic surfactant.

Preferably, the cleaning composition contains 3 to 38 wt. %, even more preferably 4 to 30 wt. % and yet even more preferably 5 to 20 wt. % of surfactants selected from alkoxylated alkyl ether sulfate surfactant, the amphoteric surfactant and the non-ionic surfactant. Most preferably, the cleaning composition does not contain any other surfactants besides the alkoxylated ether sulfate surfactant, the amphoteric surfactant and the non-ionic surfactant.

The non-ionic surfactant is preferably an alkoxylated linear alcohol, represented by the following formula (I):

CH ₃ (CH ₂ )P(0(CH ₂ )R)SOH

wherein P is an integer in the range of 8 to19;

wherein R is an integer selected from 2, 3 and combinations thereof; and wherein S is an integer in the range of 5 to 20.

More preferably the non-ionic surfactant is an ethoxylated linear alcohol, represented by the above formula (I),

wherein P is an integer in the range of 9 to 16;

wherein R is an integer selected from 2; and

wherein S is an integer in the range of 6 to 15.

Most preferably the non-ionic surfactant is an ethoxylated linear alcohol, represented by the above formula (I),

wherein P is an integer in the range of 10 to 13;

wherein R is an integer selected from 2; and

wherein S is an integer in the range of 7 to 10. Hydrogen peroxide

Hydrogen peroxide is typically present in the liquid cleaning composition in a concentration of 3 to 12 wt.%, more preferably of 3.5 to 12 wt.% and most preferably of 4 to 12 wt.%. Water

The liquid cleaning composition of the present invention is an aqueous composition that preferably contains at least 68 wt.% of water. More preferably, the cleaning composition contains 72 to 95 wt.%, most preferably 75 to 94 wt.% water. Optional ingredients

The liquid cleaning composition may suitably contain additional ingredients, such as bleach activator, builder, antimicrobial agents, preservatives, fragrance and colouring.

Besides the alkoxylated ether sulfate surfactant, non-ionic surfactant and the amphoteric surfactant, the present cleaning composition preferably contains not more than a limited amount, e.g. less than 1 wt.% of other surfactants. Even more preferably, the cleaning composition contains less than 0.5 wt.% of such other surfactants.

Preferably the cleaning composition contains less than 1wt% secondary

alkanesulfonate, even more preferably less than 0.5 wt% of the secondary

alkanesulfonates. Most preferably, the cleaning compositions does not contain any other surfactants besides the alkoxylated ether sulfate surfactant and the amphoteric surfactant.

Method of treating a fabric

In a second aspect, the present invention relates to a a method of removing stains from fabric, said method comprising the steps of

a) providing a fabric;

b) pre-treating the fabric by applying a liquid cleaning composition of the present invention as a foam onto the surface of the fabric;

c) washing the pre-treated fabric; and

d) drying the washed fabric.

According to a particularly preferred embodiment, the liquid cleaning composition is selectively applied as a foam onto stained areas of the fabric.

According to another preferred embodiment, the liquid cleaning composition is applied by spraying the liquid cleaning composition onto the fabric, especially using the cleaning system described herein. Use of the liquid cleaning composition

In a third aspect, the invention relates to the use of the liquid cleaning composition of the present invention for the removal of stains from fabric, said use comprising applying the liquid cleaning composition in the form of a foam onto the surface of the fabric. Preferably, the liquid cleaning composition is applied in the form of a foam onto the surface of the fabric by means of spraying, more preferably by spraying the liquid cleaning composition using a cleaning system as defined herein.

The invention is further illustrated by means of the following non-limiting examples.

Examples

Materials

· SLES paste (70%): Sodium lauryl ether sulphate (LES 70 2EO): Procured from Galaxy • Amine oxide (30% solution): Ν,Ν-Dimethyldodecylamine N-oxide solution, Sigma Aldrich

• Hydrogen peroxide (30% solution): Procured from Merck India.

• Dequest 2010 (1-Hydroxyl ethylidene -1 ,1 ,-diphosphonic acid, HEDP, 59%

solution): Procured from Thermphos , Switzerland

• EPEI (Ethoxylated polyethylene imine): Procured from BASF (Trade name Sokolan HP-20)

• MEA (Monoethanol amine): 100% pure, procured from Merck India

• Deionized water

· CAPB: Cocoamidopropyl betaine (30% ) from Galaxy;

• C12EO7: Ethoxylated fatty alcohol (100%) from Galaxy;

• Citric acid;

• Natrium citrate;

• MPG: Propane-1 ,2-diol (>90%) from Merck India.

Control: Vanish® stain remover spray (Market sample, Imported from Brazil) Process for preparing compositions

Each of the ingredients was added in the indicated amounts in a plastic container and was mixed using the conditions given bellow:

• Mixer type: Silversion™ Mixer

• RPM: 1500-2500

· Mixer Blade Diameter: 4 cm

• Mixer blade type: Two Flat blades at 90 degree attached to a SS rod which was fitted to the motor.

• Mixing time: 30 min for a 1 kg batch size.

• Temperature: 25 °C (Lab temperature.)

Product Format

For Examples 1 to 4 the compositions were packed in a EZ'R Squeeze Foamer bottle procured from Albea. For example 5, the compositions were packed in a trigger foam sprayer obtained from Guala Dispensing, Italy.

Process for pre-treating a fabric 0.2 to 0.7 ml of the compositions, dispensed as a foam, was applied on each stain stained on knitted cotton fabrics (ICSS1 and ICSS2 standard stain monitors procured from SUV-TUV South East Asia Pvt limited) with the help of the above mentioned foam device. After 5 minutes of application of the liquid, the pre-treated fabrics were washed.

Control:

The stains on the standard stained monitors were pre-treated with 1 .3 ml Vanish stain remover spray, followed by washing. Washing Protocol

The pre-treated standard stained monitors were washed in top-loading washing machine (Samsung). Total wash load was 5kg comprising of the pre-treated standard stained monitors and the ballast shirts. Washing was done with 60 grams Surf Excel Matic Top Load (ex. Hindustan Unilever Ltd, India) at 24°fH . A typical wash cycle comprised of soak, wash and two rinses. After washing was completed, the pre-treated and washed standard stained monitors were removed and then line-dried overnight.

Evaluation

SRI (stain removal index) was used to evaluate the efficacy of each formulation. SRI was measured for each stain using ArtixScan F1 (Innotech Scanner). The SRI values are calculated from the L, a, b values of blank and stained fabrics as follows:

For Blank (unstained) fabrics: LB, as, be

For stained fabrics: Ls, as, bs

Delta E = y .

< _s - h _B y + (a _s - a _B y + o> _s - b _B y

SRI = 100 - Delta E

Delta SRI = SRI(Expt) - SRI (Control)

Example 1

Liquid detergent compositions were prepared on the basis of the recipes shown in Table 1 . Composition 1 is an example of composition according to the present invention which is compared with compositions A-F which are not according to the invention. Vanish Stain remover (Market sample) was used as the control. Table 1

These compositions were sprayed onto the stained fabric and the pre-treated fabric was washed after this treatment following the procedure described herein before. The amount (dosage) of composition delivered by one squeeze and the washing results obtained after pre-treatment with these detergent compositions are summarized in Table 2. The higher the SRI value, the more efficacious is the composition for stain removal.

Table 2

Example 2

Liquid detergent compositions were prepared on the basis of the recipes shown in Table 3. Compositions 1to 3 are according to the present invention. Compositions A and B are not according to the invention. The compositions were filled into spray bottles as described herein before. Table 3

The viscosities of the compositions were determined. In addition, the compositions were sprayed from the spray bottle and the sprayed amount (dosage), density and quality of the foamed composition were determined. The results are shown in Table 4.

Table 4

¹ at 25°C and 20 s ^"1

Example 3

Liquid detergent compositions were prepared on the basis of the recipes shown in Table 5. Compositions 1 to 3 are according to the present invention. Compositions A and B are not according to the invention. The compositions were filled into spray bottles as described herein before. Table 5

The viscosities of the compositions were determined. The compositions were sprayed from the spray bottle and the sprayed amount (dosage) was determined. In addition, the compositions were sprayed onto the stained fabric and the pre-treated fabric was washed after this treatment following the procedure described herein before. The results are summarized in Table 6. Table 6

Example 4

Liquid detergent compositions were prepared on the basis of the recipes shown in

Table 7. Compositions 1to 3 are according to the present invention. Compositions Ato D are not according to the invention. The compositions were filled into spray bottles as described herein before. Table 7

The viscosities of the compositions were determined. The compositions were sprayed from the spray bottle and the sprayed amount (dosage) was determined. In addition, the compositions were sprayed onto the stained fabric and the pre-treated fabric was washed after this treatment following the procedure described herein before. The results are summarized in Table 8. Table 8

Example 5

Liquid detergent compositions were prepared on the basis of the recipes shown in Table 9. Compositions 1 to 4 are examples of a composition according to the present invention which is compared with composition A which is not according to the invention. Vanish Stain remover (Market sample) was used as the control. The pH for all the compositions of example 5 was within the range 2.8 to 3.2. Table 9

The viscosities of the compositions were determined. These compositions were sprayed onto the stained fabric and the pre-treated fabric was washed after this treatment following the procedure described herein before. The amount (dosage) of composition delivered by one squeeze, as well as the density and quality of the foamed composition were determined. The washing results obtained after pre- treatment with these detergent compositions are summarized in Table 10. The higher the SRI value, the more efficacious is the composition for stain removal.

Table 10

Ingredient Control 1 2 3 4 A

Dosage 1.35 ml 0.4 g 0.4 g 0.4 g 0.4 g 0.4 g

Viscosity (cps) NA < 50 < 50 < 50 < 50 >100

Foamability NA Yes Yes Yes Yes Nil

Foam density

(g/ml) NA <0.4 0.25 <0.4 0.29 >0.6

Cleaning of stains (SRI)

Dende oil 77.7 81.2 82.9 85.4 86.1

Sebum 89.5 92.8 93.7 95.5 97.4

Difficult

Garden soil 75.9 79.9 80.1 80.2 79.8

to foam

Blackberry syrup 80.4 84.2 85.2 84.4 83.6

Blood 90.1 95.2 95.3 94.7 93.6