EP1994131A1

EP1994131A1 - Composition and process

Info

Publication number: EP1994131A1
Application number: EP07732001A
Authority: EP
Inventors: Zefferino Righetto
Original assignee: Reckitt Benckiser NV
Current assignee: Reckitt Benckiser NV
Priority date: 2006-03-13
Filing date: 2007-03-12
Publication date: 2008-11-26
Also published as: WO2007104955A1; GB0605004D0

Abstract

A water free powdered composition suitable for use in a carpet cleaning operation comprises at least 30wt% precipitated / fumed silica component.

Description

COMPOSITION AND PROCESS

The present invention relates to a powdered composition suitable for cleaning carpets and a process of cleaning carpets using a powdered composition.

•

Carpets produced from synthetic or natural fibers and mixtures thereof are commonly used in residential and commercial applications as a floor covering. Various types of fibers can be used in making carpets such as polyamide fibers, polyester fibers as well as wool, cotton or even silk in the case of rugs .

Irrespective of whether the carpets are made from natural or synthetic fibers they are all prone to soiling / staining when contacted with household items. Foods, grease, oils, beverages in particular such as coffee, tea and soft drinks especially those containing acidic dyes can cause unsightly, often dark stains on carpets. Also fibres may become soiled as a result of dirt particles, clay, dust, i.e. particulate soils, coming into contact with and adhering to the fibers of the carpet . These latter soils often appear in the form of a diffuse layer of soils rather than in the form of spots and tend to accumulate particularly in the so called "high traffic areas" such as near doors as a result of intensive use of the carpets in such areas . A vacuum cleaner alone does not remove this type of soil as mere physical action is insufficient to remove it from the carpet . Compositions for the cleaning of carpets are already- known in the art. For example liquid carpet cleaning compositions based on surfactants other adjunct materials is disclosed in US-A-2005/250662.

The use of these compositions is not without their disadvantages. Firstly, whether the compositions are applied manually or with the use of an application machine, the compositions due to their liquid nature require a long time to dry typically of the order of 16 hours) from the carpet after the cleaning operation is complete.

The residual carpet cleaning liquor is associated with issues such as carpet distortion (shrinkage / expansion) , carpet discoloration, odor emanation and can even attract new dirt deposits.

One way to address these shortcomings has been to use a steam operated cleaning device. Such, steam driven de- vices do not suffer to the same extent from the problem of residual water because of the high suction power but this problem is only partially addressed because carpets cleaned in this way still take a long time to dry. Moreover the steam driven devices have the added disadvantage in that the machines are cumbersome and awkward to use.

An object of the present invention is to obviate / mitigate the problems outlined above.

According to a first aspect of the invention there is provided a water free powdered composition suitable for use in a carpet cleaning operation comprising at least 30wt% precipitated / fumed silica component .

In the context of the present application precipitated silica is understood to be a powder obtained by coagulation of silica particles from an aqueous medium under the influence of high salt concentrations / other coagulants. The term fumed silica is understood to be a powder produced by vapour phase hydrolysis of silicon tetrahalides. Fumed (pyrolitic) silica can be modified in order to obtain hydrophilic or hydrophobic fumed silica.

An advantage of composition of the present invention is that the composition is applicable to all carpet types, especially delicate natural fibers, and are also safe to all carpet dye types particularly sensitive natural dyes used therein. The composition of the present invention is also suitable to be used to clean upholstery, car seats covering and general fabrics.

Yet another advantage of the compositions of the present invention is that they may be applied directly on the carpet without causing damage to the carpet.

The term water-free is intended to mean that the composition contains less than 5wt% water, more preferably less than 3wt% water and most preferably less than lwt% water.

Generally the silica is present in the composition in an amount of greater than 40wt%, more preferably greater than 45wt% and most preferably greater than 50wt%. Generally the particle size of the silica is up to 350μm, more preferably up to 200μm, more preferably up to lOOμm, more preferably up to 50μm, more preferably up to 40μm, more preferably up to 30μm, more preferably up to 20μm, and most preferably up to lOμm.

The silica component may comprise up to 100% of the carpet cleaning composition. The composition may contain a relatively small amount of optional / additional compo- nents (see below) .

Preferred forms of silica include those supplied under the Trade Names Sipernat, Aerosil and Aeroperl (available from Degussa) ; HDK (Wacker) ; and Cab-O-Sil (Cabot) .

A preferred adjunct material incorporated into the carpet cleaning composition is a metal salt, e.g. an alkali / alkaline metal salt, such as Na, K, Ca or Mg. Preferably the metal salt such is a bicarbonate, sulphate, carbon- ate, sesquicarbonate sodium citrate or a mixture thereof.

Generally the particle size of the salt is up to 350μm, more preferably up to 200μm, more preferably up to lOOμm, more preferably up to 50μm, more preferably up to 40μm, more preferably up to 30μm, more preferably up to 20μm, and most preferably up to lOμm.

Where present the bicarbonate salt comprises an approximately equal portion of the carpet cleaning composition as the silica component. For example both components may comprise up to 50% of the carpet cleaning composition. The composition may contain a relatively small amount of optional / additional components (see below) .

The present invention encompasses a process of cleaning a " carpet comprising the use of a powdered composition comprising a precipitated / fumed silica component.

Preferably said process of cleaning a carpet further comprises the steps of:

1) applying the powdered silica containing composition to the carpet;

2) allowing the silica containing composition to interact with a stain / dirt on the carpet; and 3) at least partially removing the silica containing composition.

An advantage of the process of cleaning carpets according to the present invention is that of being easy and fast while providing excellent overall cleaning performance. More advantageously, the process of cleaning carpets according to the present invention provides excellent cleaning performance, when both used to clean the whole carpet or localized carpet stains. In addition to this, this process does not leave tacky residue on carpets. Nor is the carpet "wet" after use.

Advantageously, excellent cleaning performance is obtained on different types of stains and soils, especially in the so called "high traffic areas". The composition may be applied to the carpet in any convenient manner. The composition may be applied (e.g. manually) via a dispenser such as a rigid / flexible container having a suitable dispensing aperture. Such a dispenser may be operated by shaking over the area of carpet to be cleaned. Alternatively the composition may be applied via a mechanical device. The mechanical device can be a stand alone device or more preferably the mechanical device is attached to / associated with the composition removal device (e.g. a vacuum cleaner (see later) ) . The mechanical device may partially substitute the vacuum cleaner nozzle.

Preferably the composition is applied by a device capable of massaging the powder into the carpet for a more intimate contact with the soil adhered to the fibers. Examples of such devices are rotating / moving brush devices.

The amount of the compositions for the cleaning of car- pets according to the present invention applied will depend on the severity of the stain or soil. Generally the^' composition is applied at an amount of up to 200 g/m², more preferably up to 100 g/m², more preferably up to 50 g/m², more preferably up to 40 g/m², more preferably up to 30 g/m², more preferably up to 20 g/m², and most preferably up to 1Og / m².

In the case of stubborn stains more than one application may be required to ensure complete removal of the stain.

The area to be cleaned by applying the compositions according to the present invention may be of any size. in- deed a complete section or more preferably the whole carpet may be treated with the composition for the cleaning of carpets according to the present invention.

In a process of cleaning a carpet according to the present invention the step of applying a composition onto the carpets as described herein before, does not need to be followed by a step where manual action is required other than the final optional removing step . Indeed the compositions herein allow excellent cleaning performance without requiring any manual action (e.g. rubbing / brushing. An advantage of the present invention is that the cleaning action of the composition commences as soon as it is applied onto said carpet.

Typically, the composition is left on the carpet for less than 2 hours, preferably less than 1 hour, more preferably less than 40 minutes, even more preferably less than 30 minutes, more preferably less than 20 minutes and most preferably less than 10 minutes. One option is to simultaneously apply the composition, massage it into the carpet and vacuum it away.

Preferably said composition is then removed from the car- pet. More preferably said composition is removed mechanically, even more preferably by vacuum cleaning, more preferably with a vacuum cleaner equipped with a beater (brushes) . This may be carried out with any commercially available vacuum cleaner.

The composition generally comprises other detergent actives . Where present it is preferred that the detergent active is powdered. (The detergent active itself may be in solid powdered form or may be a liquid which is capable of being converted into a powder when brought into contact with another component of the composition (e.g. by spraying) . Most preferably the powdered detergent active has a particle size similar to that of the silica.

Surfactants may be present in the composition in an amount of, for example, 0.001 to 30% wt, ideally 0.01 to 15% wt and preferably 0.1 to 5% wt . The surfactant is, for example, an anionic or nonionic surfactant or mixture thereof. The nonionic surfactant is preferably a surfac- tant having a formula RO (CH₂CH₂O) nH wherein R is a mixture of linear, even carbon-number hydrocarbon chains ranging from Ci₂H₂S to Ci₆H₃₃ and n represents the number of repeating units and is a number of from about 1 to about 12. Examples of other non-ionic surfactants in- elude higher aliphatic primary alcohol containing about twelve to about 16 carbon atoms which are condensed with about three to thirteen moles of ethylene oxide.

Other examples of nonionic surfactants include primary alcohol ethoxylates (available under the Neodol tradename from Shell Co.), such as Cu alkanol condensed with 9 moles of ethylene oxide (Neodol 1-9) , Ci₂-I₃ alkanol condensed with 6.5 moles ethylene oxide (Neodol 23-6.5), C_i2_ ₁₃ alkanol with 9 moles of ethylene oxide (Neodol 23-9) , C₁₂-i₅ alkanol condensed with 7 or 3 moles ethylene oxide (Neodol 25-7 or Neodol 25-3) , Ci₄-I₃ alkanol condensed with 13 moles ethylene oxide (Neodol 45-13) , C₉-n linear ethoxylated alcohol, averaging 2.5 moles of ethylene oxide per mole of alcohol (Neodol 91-2.5), and the like.

Other examples of suitable nonionic surfactants include ethylene oxide condensate products of secondary aliphatic alcohols containing 11 to 18 carbon atoms in a straight or branched chain configuration condensed with 5 to 30 moles of ethylene oxide. Examples of commercially available non-ionic detergents of the foregoing type are Cn-_I5 secondary alkanol condensed with either 9 moles of ethylene oxide (Tergitol 15-S-9) or 12 moles of ethylene oxide (Tergitol 15-S-12) marketed by Union Carbide.

Other examples of linear primary alcohol ethoxylates are available under the Tomadol tradename such as, Tomadol 1- 7, a Cn linear primary alcohol ethoxylate with 7 moles EO; Tomadol 25-7, a C₁₂-1₅ linear primary alcohol ethoxylate with 7 moles EO; Tomadol 45-7, a Ci₄._1S linear primary alcohol ethoxylate with 7 moles EO; and Tomadol 91-6, a C₉-₁₁ linear alcohol ethoxylate with 6 moles EO.

Other nonionic surfactants are amine oxides, alkyl amide oxide surfactants.

Preferred anionic surfactants are frequently provided as alkali metal salts, ammonium salts, amine salts, aminoal- cohol salts or magnesium salts. Contemplated as useful are sulfate or sulfonate compounds including: alkyl benzene sulfates, alkyl sulfates, alkyl ether sulfates, al- kylamidoether sulfates, alkylaryl polyether sulfates, monoglyceride sulfates, alkylsulfonates, alkylamide sulfonates, alkylarylsulfonates, olefinsulfonates, paraffin sulfonates, alkyl sulfosuccinates, alkyl ether sulfosuc- cinates, alkylamide sulfosuccinates, alkyl sulfosuccina- mate, alkyl sulfoacetates, alkyl phosphates, alkyl ether phosphates, acyl sarconsinates, acyl isethionates, and N- acyl taurates. Generally, the alkyl or .acyl radical in these various compounds comprise a C₁₂-₂o carbon chain.

Other surfactants which may be μsed are alkyl naphthalene sulfonates and oleoyl sarcosinates and mixtures thereof.

Examples of suitable bleaches are oxygen bleaches. Suitable level of oxygen bleaches is in the range from 0.01 to 90% wt. As used herein active oxygen concentration refers to the percentage concentration of elemental oxy- gen, with an oxidation number zero, that being reduced to water would be stoichiometrically equivalent to a given percentage concentration of a given peroxide compound, when the peroxide functionality of the peroxide compound is completely reduced to oxides. The active oxygen sources increase ^• the ability of the compositions to remove oxidisable stains, to destroy malodorous molecules and to kill germs.

The concentration of available oxygen can be determined by methods known in the art, such as the iodimetric method, the permanganometric method and the cerimetric method. Said methods and the criteria for the choice of the appropriate method are described for example in "Hydrogen Peroxide", W. C. Schumo, C. N. Satterfield and R. L. Wentworth, Reinhold Publishing Corporation, New York, 1955 and "Organic Peroxides" , Daniel Swern, Editor Wiley Int. Science, 1970. Suitable organic and inorganic peroxides for use in the compositions according to the present invention include diacyl and dialkyl peroxides such as dibenzoyl peroxide, dilauroyl peroxide, dicumyl peroxide, persulphuric acid and mixtures thereof .

Suitable preformed peroxyacids for use in the compositions according to the present invention include diper- oxydodecandioic acid DPDA, magnesium perphthalatic acid, perlauric acid, perbenzoic acid, diperoxyazelaic acid and mixtures thereof. Peroxygen bleaching actives useful for this invention are: percarbonates, perborates, peroxides, peroxyhydrates, persulfates. A preferred compound is so- dium percarbonate and especially the coated grades that have better stability. The percarbonate can be coated with silicates, borates, waxes, sodium sulfate, sodium carbonate and surfactants solid at room temperature.

Optionally, the composition may comprise from 0.1% to 30%, preferably from 2% to 20% of peracid precursors, i.e. compounds that upon reaction with hydrogen peroxide product peroxyacids. Examples of peracid precursors suitable for use in the present invention can be found among the classes of anhydrides, amides, imides and esters such as acetyl triethyl citrate (ATC) described for instance in EP 91 87 0207, tetra acetyl ethylene diamine (TAED), succinic or maleic anhydrides.

The composition may comprise a builder or a combination of builders, for example in an amount of from 0.01 to 50%wt, preferably from 0.1 to 20%wt. Examples of builders are described below:

- the parent acids of the monomeric or oligomeric poly- carboxylate chelating agents or mixtures therefore with their salts, e.g. citric acid or citrate/citric acid mixtures are also contemplated as useful builder components.

- borate builders, as well as builders containing borate- forming materials than can produce borate under detergent storage or wash conditions can also be used. - iminosuccinic acid metal salts

- polyaspartic acid metal salts.

- ethylene diamino tetra acetic acid and salt forms.

- water-soluble phosphonate and phosphate builders are useful for this invention. Examples of phosphate buiders are the alkali metal tripolyphosphates, sodium potassium and ammonium pyrophosphate, sodium and potassium and ammonium pyrophosphate, sodium and potassium orthophosphate sodium polymeta/phosphate in which the degree of polymerisation ranges from 6 to 21, and salts of phytic acid. Specific examples of water-soluble phosphate builders are the alkali metal tripolyphosphates, sodium potassium and ammonium pyrophosphate, sodium and potassium and ammonium pyrophosphate, sodium and potassium orthophosphate, sodium polymeta/phosphate in which the degree of polymeri- zation ranges from 6 to 21, and salts of phytic acid. Such polymers include the polycarboxylates containing two carboxy groups include the water-soluble salts of succinic acid, malonic acid, (ethylenedioxy) diacetic acid, maleic acid, diglycolic acid, tartaric acid, tartronic acid and fumaric acid, as well as the ether carboxylates and the sulfinyl carboxylates . Polycarboxylates containing three carboxy groups include, in particular, water-soluble citrates, aconitrates and citraconates as well as succinate derivates such as the carboxymethloxysuccinates described in GB-A-I, 379, 241, 5 lactoxysuccinates described in GB-A-I, 389, 732 , and amino- succinates described in NL-A-7205873 , and the oxypolycar- boxylate materials such as 2-oxa-l, 1, 3 -propane tricar- boxylates described in GB-A-I, 387, 447.

10 Polycarboxylate containing four carboxy groups include oxydisuccinates disclosed in GB-A-I, 261, 829, 1,1,2,2- ethane tetraca'rboxylates, 1,1,3,3 -propane tetracarboxy- lates and 1 , 1 , 2 , 3 -propane tetracarobyxlates . Polycarboxylates contining sulfo substituents include the sulfo-

15 succinate derivatives disclosed in GB-A-I, 398,421, GB-A- 1,398,422 and US-A-3 , 936448 , and the sulfonated pyrolsed citrates described in GB-A-I, 439, 000.

Alicylic and heterocyclic polycarboxylates include 20. cyclopentane-cis,cis,cis-tetracarboxylates, cyclopentadi- enide pentacarboxylates, 2 , 3 , 4, 5, 6-hexane - hexacarboxy- lates and carboxymethyl derivates of polyhydric alcohols such as sorbitol, mannitol and xylitol. Aromatic polycarboxylates include mellitic acid, pyromellitic acid and 25 phthalic acid derivatives disclosed in GB-A-I, 425, 343.

Of the above, the preferred polycarboxylates are hydroxy- carboxylates containing up to three carboxy groups per molecule, more particularly citrates. 0

Suitable polymers include the water soluble monomeric polycarboxylates, or their acid forms, homo or copoly- meric polycarboxylic acids or their salts in which the polycarboxylic acid comprises at least two carboxylic radicals separated from each^" other by not more than two carbon atoms, carbonates, bicarbonates, borates, phos- phates, and mixtures of any of thereof.

The carboxylate or polycarboxylate builder can be mono- meric or oligomeric in type although monomeric polycar- boxylates are generally preferred for reasons of cost and performance .

Suitable carboxylates containing one carboxy group include the water soluble salts of lactic acid, glycolic acid and ether derivatives thereof. Polycarboxylates containing two carboxy groups include the water-soluble salts of succinic acid, malonic acid, (ethylenedioxy) di- acetic acid, maleic acid, diglycolic acid, tartaric acid, tartronic acid and fumaric acid, as well as the ether carboxylates and the sulfinyl carboxylates. Polycarboxy- lates containing three carboxy groups include, in particular, water-soluble citrates, aconitrates and citra- conates as well as succinate derivates such as the car- boxymethloxysuccinates described in GB-A-I, 379, 241, lac- toxysuccinates described in GB-A-I, 389, 732, and aminosuc- cinates described in NL-A-7205873 , and the oxypolycar- boxylate materials such as 2-oxa-l, 1, 3 -propane tricar- boxylates described in GB-A-I, 387, 447.

Polycarboxylate containing four carboxy groups include oxydisuccinates disclosed in GB-A-I, 261, 829, 1,1,2,2- ethane tetracarboxylates, 1, 1, 3 , 3 -propane tetracarboxy- lates and 1 , 1 , 2 , 3 -propane tetracarboxylates. Polycar- boxylates contining sulfo suibstitu.ents include the sul- fosuccinate derivatives disclosed in GB-A-I, 398,421, GB- A-I, 398, 422 and US-A-3 , 936448, and the sulfonated pyrol- sed citrates described in GB-A-I, 439, 000.

Alicylic and heterocyclic polycarboxylates include cyclopentane-cis,cis,cis-tetracarboxylates, cyclopentadi- enide pentacarboxylates, 2, 3 , 4, 5, 6-hexane - hexacarboxy- lates and carboxymethyl derivates of polyhydric alcohols such as sorbitol, mannitol and xylitol. Aromatic polycarboxylates include mellitic acid, pyromellitic acid and phthalic acid derivatives disclosed in GB-A-I, 425, 343.

Of the above, the preferred polycarboxylates are hydroxy- carboxylates containing up to three carboxy groups per molecule, more particularly citrates.

More preferred polymers are homopolymers , copolymers and multiple polymers of acrylic, fluorinated acrylic, sul- fonated styrene, maleic anhydride, metacrylic, iso- butylene, styrene and ester monomers.

Examples of these polymers are Acusol supplied from Rohm & Haas, Syntran supplied from Interpolymer and Versa and Alcosperse series supplied from Alco Chemical, a National Starch & Chemical Company.

The parent acids of the monomeric or oligomeric polycar- boxylate chelating agents or mixtures therefore with their salts, e.g. citric acid or citrate/citric acid mixtures are also contemplated as useful builder components. In the context of- the present application it will be appreciated that, builders are compounds that sequester metal ions associated with the hardness of water, e.g. calcium and magnesium, whereas chelating agents are com- pounds that sequester transition metal ions capable of catalysing the degradation of oxygen bleach systems. However, certain compounds may have the ability to, do perform both functions.

Suitable chelating agents to be used herein include chelating agents selected from the group of phosphonate chelating agents, amino carboxylate chelating agents, poly- functionally-substituted aromatic chelating agents, and further chelating agents like glycine, salicylic acid, aspartic acid, glutamic acid, malonic acid, or mixtures thereof. Chelating agents when used, are typically present herein in amounts ranging from 0.01% to 50%wt of the total composition and preferably from 0.05% to 10%wt.

Suitable phosphonate chelating agents to be used herein may include ethydronic acid as well as amino phosphonate compounds, including amino alkylene poly (alkylene phosphonate) , alkali metal ethane 1-hydroxy diphosphonates, nitrilo trimethylene phosphonates, ethylene diamine tetra methylene phosphonates, and diethylene triamine penta methylene phosphonates . The phosphonate compounds may be present either in their acid form or as salts of different cations on some or all of their acid functionalities. Preferred phosphonate chelating agents to be used herein are diethylene triamine penta methylene phosphonates. Such phosphonate chelating agents are commercially available from Monsanto under the trade name DEQUEST TM. PolyfunctionalIy-substituted aromatic chelating agents may also be useful in the compositions herein. See U.S. patent 3,812,044. Preferred compounds of this type in acid form are^' dihydroxydisulfobenzenes such as 1,2- dihydroxy -3 , 5-disulfobenzene.

A preferred biodegradable chelating agent for use herein is ethylene diamine N,N' -disuαcinic acid, or metal / am- monium salts thereof. Ethylenediamine N, N' -disuccinic acids is, for instance, commercially available under the tradename ssEDDS TM from Palmer Research Laboratories .

Suitable amino carboxylates include ethylene diamine tetra acetates, diethylene triamine pentaacetates, di- ethylene triamine pentaacetate (DTPA) , N- hy- droxyethylethylenediamine triacetates, nitrilotri- acetates, ethylenediamine tetrapropionates, triethylene- tetraaminehexa-acetates, ethanol-diglycines, propylene diamine tetracetic acid (PDTA) MGDA, in their acid form, or in their alkali metal, ammonium, and substituted ammonium salt forms. Particularly suitable amino carboxylates to be used herein are DTPA, propylene diamine tetracetic acid which is commercially available from BASP under the trade name Trilon FS TM.

Solvents can be used for present invention at levels of 0.01 to 30%wt, more preferred level is between 0.1 and 20%, more preferred between 0.1 and 10%. The solvent constituent may include one or more alcohol, glycol, acetate, ether acetate, glycerol, polyethylene glycol with molecular weight ranging from 200 to 1000, silicones or glycol ethers. Exemplary alcohols useful in the compositions of the invention include C₂.₈ primary and secondary alcohols which may be straight chained or branched, preferably pentanol and hexanol . Exemplary silicones useful in the compositions of the invention include cyclic silicones (cyclomethicones) like DC 244 Fluid, DC 245 Fluid, DC 246 Fluid, DC 344 Fluid; silicone polyether like DC 190 and DC 193.

Preferred solvents for the invention are glycol ethers and examples include those glycol ethers having the general structure. Preferred solvents for the invention are glycol ethers and examples include those glycol ethers having the general structure Ra-O- [CH₂-CH (R) - (CH₂) -O]_n-H, wherein Ra is Ci-₂o alkyl or alkenyl, or a cyclic alkane group of at least 6 carbon atoms, which may be fully or partially unsaturated or aromatic; n is an integer from 1 to 10, preferably from 1 to 5; each R is selected from H or CH₃; and a is the integer 0 or 1. Specific and pre- ferred solvents are selected from propylene glycol methyl ether, dipropylene glycol methyl ether, tripropylene gly- _.col methyl ether, propylene glycol n-propyl ether, ethylene glycol n-butyl ether, diethylene glycol n-butyl ether, diethylene glycol methyl ether, propylene glycol, ethylene glycol, isopropanol, ethanol , methanol, diethylene glycol monoethyl ether acetate, and particularly useful are, propylene glycol phenyl ether, ethylene glycol hexyl ether and diethylene glycol hexyl ether.

The composition may comprise an enzyme. Example of suitable enzymes are proteases, modified proteases stable in oxidisable conditions, amylases and lipases. Additionally, optional ingredients may be included. Suitable optional ingredients comprise optical bright- eners , fragrances, dyes.

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

EXAMPLES

Soil application

A 30 x 30 cm carpet is used for the soil removal evaluation. Soil is applied according to ASTM-D6540 methodol- ogy using the AATCC 123 artificial soil to obtain a ΔE value (soiled-virgin) of about 6.

Cleaning method

^• The formulations were homogeneously applied on the carpet using a sieve-like applicator. The powder was worked into the carpet by using the rotating brush of a Dyson nC-04 upright vacuum cleaner with the suction excluded. 2 strokes (1 stroke equal to 1 back and forth pass over the carpet) for your reference 2 strokes equal 4 total passes over a same point on the carpet were used to work the powder into the carpet .

The powder is left to act on the carpet for 5 minutes and then it is vacuumed by using the same vacuum cleaner with the suction on. 2 strokes were used to. remove the powder. In another testing, the powder is vacuumed by using the same vacuum cleaner with the suction on immediately after application. 2 strokes were used to work and vacuum the powder .

The cleaned carpet is read with a Minolta Chromameter CR- 400. The soil removal % is obtained by the ratio between the ΔE (cleaned-soiled) and the ΔE (soiled-virgin) . The higher the soil removal % the better the cleaning efficacy of the formulation.

Formulations Tested

Results

Claims

1. A water free powdered composition suitable for use in a carpet cleaning operation comprising at^' least 30wt% precipitated / fumed silica component.

2. A composition according to claim 1, wherein the silica is present in the composition in an amount of greater than 40wt%, more preferably greater than 45wt% and most preferably greater than 50wt%.

3. A composition according to claim 1 or 2, wherein the particle size of the silica is up to 350μm, more prefera- bly up to 200μm, more preferably up to lOOμm, more preferably up to 50μm, more preferably up to 40μm, more preferably up to 30μm, more preferably up to 20μm, and most preferably up to lOμm.

4. A composition according to claim 1, 2 or 3, wherein the composition comprises a metal salt, e.g.. an alkali metal salt (Na, K, Ca, Mg) , such as a bicarbonate, sulphate, carbonate, sesquicarbonate, sodium citrate or a mixture thereof.

5. A composition according to claim 4, wherein the metal salt comprises an approximately equal portion of the carpet cleaning composition as the silica component.

6. A composition according to any one of claims 1 to 5 , wherein the composition comprises a further detergent active.

7. A water free powdered composition suitabl.e for use in a carpet cleaning operation comprising at least 30wt% precipitated / fumed silica component, at least 30wt% inorganic metal salt, a solvent and a detergent active.

8. A process of cleaning a carpet comprising the use of a water free powdered composition comprising at least 30wt% precipitated / fumed silica component.

9. A process according to claim 8, wherein the process comprises the steps of:

1) applying the powdered silica containing composition to the carpet;

2) allowing the silica containing composition to inter- act with a stain / dirt on the carpet ; and

3) at least partially removing the silica containing composition.

10. A process according to claim 9, wherein in step (3) the removal is carried out using a vacuum cleaner..

11. A process according to claim 9 or 10, wherein the silica com position is applied at an amount of around 1Og / m². ^'