MXPA02009578A - Solid dispersible abrasive compositions. - Google Patents

Abstract

The invention provides dry compositions comprising a solid abrasive (preferably at least 65 %) and a suspending system (preferably at least 0.1 %) suitable to obtain a stable suspension on mixing with a liquid medium. Suitable suspending systems are based on a surfactants or surfactant mixtures which are able to form a lamellar micelle phase after mixing with the liquid medium or on polymeric thickening systems. The preferred liquid medium is water. The dry abrasive compositions are free flowing and easily dispersible in water by the consumer to obtain a ready to use liquid abrasive cleaner.

Description

SOLID COMPOSITIONS DISPERSIBLE ABRASIVE FIELD OF THE INVENTION The invention relates to solid compositions containing an abrasive and suitable to be dispersed in water to obtain a liquid abrasive cleaning composition for cleaning hard surfaces.

BACKGROUND OF THE INVENTION Liquid abrasive cleaning compositions for hard surfaces are well known in the art and usually comprise a combination of detergent surfactants, in particular anionic and nonionic surfactants, which together form a lamellar phase of micelles and thus cause thicke of the liquid. The lamellar phase acts as a suspension system to keep the solid abrasive in a stable suspension. Frequently, an electrolyte and / or a polymeric thickener is added to further improve the stability of the suspension. Thus, in WO 91/08283, liquid abrasive cleaning compositions comprising 0.02-20% detergent, 1-70% particulate abrasive and 0.01-10% of a thickener mixture consisting of a polymer of non-toxic type are described. linear starch and a branched starch polymer (amylopectin). The non-starch type polymers include various natural gums and synthetic polymers. In particular, partially acetylated xanthan is preferred. In practice, the required amounts of thickener mixture are about 3% by weight of the composition total and the examples all specify 1.5% non-ionic surfactant. In WO 95/0861 9, there are described liquid cleaning compositions, comprising a crosslinked polyacrylate, either at least one nonionic surfactant or a combination of an anionic surfactant and a nonionic surfactant, a pH adjusting agent and a abrasive calcium carbonate. The compositions are said to contain 0.1-2% polyacrylate, 0.1-10% nonionic, up to 10% anionic and 5-60% abrasive. In practice, according to the examples, they contain 0.25-0.4% polymer, 0.5% or more nonionic and 40% abrasive. The non-ionic is required to provide the correct viscosity characteristics. Similar compositions are described in EP 649898 with the extra condition that they contain hypochlorite and that the surfactant is stable to the bleach. In EP-A-0 875 557, an aqueous thickener composition suitable for a variety of end applications is described, which comprises 0.04-30% w / w of a mixture of at least two surfactants in a specific ratio and with a difference in HLB of at least 1 unit and 0.01 -5% w / w of an associative thickener selected from hydrophobically modified hydroxyethylcellulose, hydrophobically modified nonionic polyol and hydrophobically modified alkali-soluble emulsion polymer. In practice, the amount of associative thickener is 1-2% and the amount of surfactant mixture 1-10%. The liquid abrasive cleaning compositions for hard surfaces are usually sold in a ready-to-use form, which contains 1 0-50%, in most cases 30-45% solid abrasive.

Such compositions can not be diluted to, for example, 10-20% solid abrasive content without losing their stability leading to sedimentation. Although in the patent literature, abrasive contents of up to 70% are cited, such contents are not normally found in commercial products. Before liquid abrasive cleaners became popular, it was customary in some countries to still clean hard surfaces using abrasive powder compositions. Such compositions consist almost entirely of powdered abrasive, that is, for 95% or more, with a small amount (< 5%) of a foaming surfactant. The compositions are applied directly on the hard surface to be cleaned and used with a small amount of water, such as is present in a wet cloth. The surfactant aids in cleaning by improving the wetting properties of the water / abrasive mixture on the surface, and also provides a visual cleaning signal for the foam that is generated. Thus, PL 1 53680 describes solid abrasive cleaning compositions containing 45-95% ground quartz, feldspar or glass, 1.5-23% synthetic anionic or nonionic surfactants (in particular oxide copolymer). of alkylene and Na LAS), a chlorine bleach compound, 0.1 -50 phosphoric acid / urea complex and 0. 1 -25% of its Na. G B 1, 339, 274 describes similar compositions further comprising a compound that generates heat over the mixture with water during the cleaning operation. RU 2106376 describes a powder abrasive cleaner containing ground quartz and sodium polyacrylate as a surfactant The product is intended to be used as a classic powder abrasive. JP-A-02029497 discloses abrasive cleaners, which may be in the form of a powder, or a liquid, and which contain hydroxyapatite as an abrasive and a surfactant. EP-A-0 821 721 discloses ready-to-use abrasive powders containing a mixture of carbonate and sodium bicarbonate as a water-soluble abrasive, an anionic detergent and a solid hypochlorite bleach. The prior art abrasive cleaning compositions can not be converted into liquid abrasive cleaning compositions by simply adding a suitable amount of water, because the surfactant present in the powder mixture does not intend, and would be incapable of, forming the phase. micellar lamella required to keep the solid abrasive in stable suspension. In this way, the abrasive would quickly separate and settle to the bottom of the container. However, it would be useful to have a dry mix available, either in the form of a powder or granules or other suitable solid form, which acts as an intant, liquid abrasive cleaner, ie, becomes an abrasive liquid cleaner. Ready and stable about adding an adequate amount of water. In this way, the costs of packing and transport involved in shipping large quantities of water could be saved and storage conditions that adversely affect the stability of a ready-made system could be avoided. Dry abrasive soap powders are also known to remove difficult dirt from the skin. Such products are described, by example, in US 4786432 and US 4786369. They consist of abrasive particles coated with an anionic surfactant mostly fatty acid soap. The soap powders generally contain less than about 80% abrasive and in most cases no more than about 50%. EP-B-0 796 31 8 discloses free flowing solid preparations intended to clean hands. The compositions are obtained by fluidized bed drying and granulation of a mixture of a detergent paste and an abrasive selected from pumice stone, milled wood, ground walnut shells or vegetable fibers. Such powders do not intend to be mixed with water before use and the soap system used therein does not have any suspension property for the abrasive. WO 94/25563 discloses tablets, blocks or articles with similar shape comprising surfactants and optionally abrasives. They are intended to be used in cleaning machinery and are clearly not suitable for transfer in a stable suspension. It is mentioned in it that the blocks and their use avoid the need for a suspension system. However, there is no indication that any of the solid products described above could be converted into a stable suspension.

BRIEF DESCRIPTION OF THE INVENTION The invention provides dry solid compositions, which can be mixed with a liquid medium to provide a ready-to-use, stable, hard surface abrasive cleaning composition for hard surfaces. In this way, the dry compositions comprise a solid abrasive and a suspension system, which keeps the abrasive in a stable suspension after mixing with the liquid medium. The invention also provides a process for preparing liquid abrasive cleaning compositions comprising the step of mixing a dry composition, which comprises a solid abrasive and a suspension system, with a liquid medium, without the need for any additional mixing of the additional components . In addition, the invention provides liquid abrasive cleaning compositions obtained in accordance with the process described above.

DETAILED DESCRIPTION OF THE INVENTION All percentages given herein are by weight of the total composition unless otherwise specified. The dry abrasive compositions according to the invention comprise as essential ingredients, a solid abrasive as the main component, preferably in an amount of at least 55%, and a suitable suspension system to obtain a stable suspension upon mixing with the liquid medium, preferably in an amount of at least 0.1 %. Additionally, the compositions comprise as a highly desirable but optional component, a foaming surfactant, preferably in an amount of at least 0.1%. The dry compositions are suitable for the consumer to be mixed by the same at home with a liquid medium, to obtain the liquid abrasive cleaner ready for use. Alternatively, the Dry compositions can be shipped to a factory where simple mixing equipment is sufficient to convert the dry composition into a liquid ready-to-use abrasive composition ready to pack and transport to the consumer. The liquid medium can be any liquid, which is suitable and safe for use by the consumer. In this way, it should be harmless to health and preferably non-flammable. The obvious choice is water, but some organic solvents or mixtures of such solvents with water may also be suitable. Preferably, the medium consists of at least 85% water. Preferably, the amount of abrasive in the dry composition is at least 65%, more preferably at least 70% or even 75%. The abrasive may be any fine particulate solid known in the art for its convenience as an abrasive material. Most of the known materials are insoluble in water, however, suitable materials are also known, which are soluble in water. Preferred abrasives have a Moh hardness of 6 or less, although higher hardness abrasives may be used for special applications. In general, the lower the abrasiveness of the abrasive materials, the lower the damage to the surface, although a hardness of 1 or more is preferred to give a sufficient cleaning capacity. Suitable water-insoluble abrasives can be selected from synthetic as well as naturally occurring (minerals) and example include: zeolites, silicas, silicates, carbonates, alumina and organic polymeric abrasives, such as polyethylene, polycarbonate, polyurethane, polystyrene, polypropylene, polyethylene terephthalate, polymethyl methacrylate and nylon, and mixtures thereof. Preferred abrasives are: calcium carbonate (such as calcite), calcium carbonate and magnesium mixtures (such as dolomite), zeolite, alumina, hydrated alumina, feldspar, talc and silica. Calcite and dolomite and mixtures thereof with lower amounts of silica, especially amorphous silica, are particularly preferred because of their low cost and good abrasive properties. Suitable water-soluble abrasives include sodium carbonate, sodium bicarbonate, sodium tripolyphosphate, sodium borate and potassium sulfate. An abrasive soluble in water upon mixing with water, produces a saturated aqueous solution of the abrasive and a solid phase of undissolved abrasive particles suspended in the aqueous solution. Such liquid abrasive cleaning compositions have been described, for example, in EP-A-0 193 375. Preferred average weight particle sizes for abrasives fall in the range of 0.5-500 microns, particularly preferring values of about 1 0-1 00 mins. In this range, an acceptable average term is achieved between good cleaning behavior and low substrate damage. However, for silica to be used in combination with calcite or dolomite, an average particle size in the range of 200-500 microns is also very suitable. The suspension system can be any suspension system known in the art for suspending abrasive particles in a liquid abrasive cleaner. Liquid abrasive cleaners ready to use Satisfactory results obtained from the dry abrasive compositions according to the invention, should have such fluid flow characteristics so that they are stable suspensions when not in use, but sufficiently fluid to empty the liquid from the container and spread it over the surface soiled without looking thin and watery. In this way, the type and amount of suspension system is chosen so that the suspension obtained after mixing the dry composition with an equal amount of water has the following flow properties: ? 0 is at least 2500 Pa.s sc is 2.5-25? 21 is at least 0.1 Pa. S where:? 0 is the viscosity at zero shear rate; sc is the shear stress at which the viscosity is 0. 1? 0; and? 2? is the viscosity at the cutting speed of 21 s "1. Preferably? 21 is 0.3-5.0, more preferably 0.6-1.8, m and preferably 1.0-0.5 Pa. s. : CASL 100 (TA Instruments) with pallet and basket measuring system (internal diameter of basket 48, inner diameter of pallet of 38 mm and height of 24.5 mm) to measure the viscosity from a voltage (s) of 0.01 Pa to the tension required to give a cutting speed of 1 s "1. Haake RV20 with M5 measuring head and SV2p measurement geometry to measure the viscosity between cutting speeds of 0. 1 and 389 s "1. All measurements are made at 20 ° C. Well-known suspension systems comprise a surfactant mixtures of surfactant, preferably in combination with an electrolyte, in such a amount and proportion that the total combination is capable of forming a lamellar phase of micelles.This surfactant, or one or more of these surfactants, can be a foaming surfactant, in which case it is superfluous to add an optional extra foaming surfactant, in order to obtaining the desired foaming properties Preferably, the surfactant, or one or more of these surfactants, is (are) anionic.

Very suitable suspension systems can be obtained by combining an anionic surfactant with an electrolyte, a nonionic surfactant or a cationic surfactant. Particularly suitable systems comprise an anionic surfactant and a nonionic surfactant, if desired, further supplemented with an electrolyte. Such suspension systems are preferably comprised in the dry abrasive composition as follows: • 0.5-30%) of anionic surfactant, preferably 1.5-25%, more preferably 2.5-20%; • 0.2-20% or non-ionic surfactant, preferably 1.0-0.5%), more preferably 1.5- 12%. Suitable anionic surfactants are water-soluble salts of organic esters of sulfuric acid and sulfonic acids, which have in their molecular structure an aliphatic group containing from 8 to 22 carbon atoms.

I I Suitable examples thereof are the following water-soluble salts: long-chain aliphatic alcohol sulphates, especially those obtained by sulfating the higher alcohols produced by reducing the glycerides of vegetable or animal oils or fats, such as tallow or coconut oil; alkylbenzene sulfonates, such as those in which the alkyl group contains from 6 to 20 carbon atoms; - secondary and primary alkanesulfonates; - alkyl glyceryl ether sulfates, especially those ethers of the higher alcohols derived from tallow and coconut oil; fatty acid monoglyceride sulfates; sulfates of ethoxylated fatty alcohols containing 1-6 units of EO in the molecule; sulfates of alkylphenol ethoxylates containing 1 -8 units of EO and in which the alkyl radicals contain 4-14 carbon atoms; the reaction product of fatty acids, for example, those derived from coconut oil, esterified with isethionic acid and neutralized with sodium hydroxide; and mixtures thereof. Suitable anionic water-soluble synthetic anionic surfactant components of a suspension system are: sodium, potassium and magnesium alkyl benzenesulfonates, olefin sulphonates, alkyl sulfates, and mono-glyceride sulfates of fatty acids. These surfactants also function conveniently as foaming surfactants.

In the absence of a source of calcium ions (such as calcite or dolomite), fatty acid soaps are also suitable as anionic surfactants. Even in the presence of Ca ions, a small amount of fatty acid (< 4.5%) can still be usefully added to improve the stability of the suspension after dilution. A class of suitable non-ionic surfactants can be broadly described as compounds produced by the condensation of alkylene oxide groups, which are hydrophilic in nature, with an organic hydrophobic compound, which may be aliphatic or alkyl aromatic in nature. The length of the hydrophilic or polyoxyalkylene radical, which is attached to any particular hydrophobic group, can be easily adjusted to produce a suitable soluble compound having the desired nce between hydrophilic and hydrophobic elements. This allows the choice of non-ionic surfactants with the correct HLB. Particular examples include: the condensation products of aliphatic alcohols having from 8 to 22 carbon atoms either in straight chain or branched configuration with ethylene oxide, such as ethylene oxide coconut alcohol condensates, having from 2 to 1 5 moles of ethylene oxide per mole of coconut alcohol; condensates of alkylphenols whose alkyl group contains from 6 to 12 carbon atoms with 2 to 25 moles of ethylene oxide per mole of alkylphenol; - condensates of the reaction product of ethylene diamine and propylene with ethylene oxide, the condensates containing from 40 to 80% of ethyleneoxy groups by weight and having a molecular weight from 5,000 to 1 1,000. Other classes of nonionic surfactants are: - tertiary amine oxides of general structure RRRNO wherein one R is an aliphatic group of 8 to 1 8 carbon atoms and the other R are each alkyl or hydroxyalkyl groups of 1 to 3 carbon atoms, for example, dimethyldodecylamine oxide; tertiary phosphino oxides of structure RRRPO, where one R is an aliphatic group of 8 to 18 carbon atoms and the other R are each alkyl or hydroxyalkyl groups of 1 to 3 carbon atoms, for example, dimethyl dodecylphosphine oxide; dialkyl sulfoxides of structure RRSO, wherein one R is an alkyl group from 10 to 18 carbon atoms and the other is methyl or ethyl, for example, methyltetradecyl sulfoxide; fatty acid alkylolamides; alkylene oxide condensates of fatty acid alkylolamides; alkyl mercaptans. Condensates of aliphatic alcohol ethylene oxide and amine oxides are particularly suitable components of a suspension system. The amine oxides also function conveniently as foaming surfactants. Other well-known suspension systems comprise one or more polymeric thickening agents. The polymers in such systems can be of natural or synthetic origin. Suitable polymers are frequently of the anionic type. They are available in emulsion and in solid form. Additionally, they can be modified hydrophobically and / or crosslinked. Such polymers include polycarboxylate type polymers, such as acrylate, methacrylate and homopoiomers and copolymers of maleic anhydride, and various polysaccharides, such as carboxymethylcelluloses, hydroxyethylcellulose, hydroxypropylmethylcellulose, carrageenan, alginate, tragacanth gum, locust bean gum, guar gum , etc. The polymers should dissolve and thicken easily in cold water without forming lumps. Examples of suitable polymers include: serides ACUSOL HASE and ASE, such as 820, 823 and 842; POLYGEL / NEUTRAGEL series, such as W30, DA, DS, DR and DB; RHEOV1S series, such as CRX CARBOPOL series, such as Aqua 30, ETD 2690, ETD 2691, ETD 2623, EZ-1, EZ-2, EP-1, LNP-3, 663, 664 and 674; PEMULEN series, such as TR1 and TR2; STRUCTURE 2001, 3001; ALCOGUM SL-70 and SL-78.

ACUSOL is a trademark of Rohm & Haas; CARBOPOL and PEMULEN are trademarks of B F Goodrich; POLYGEL and NEUTRAGEL are trademarks of Sigma 3V; RHEOVIS is a trademark of Ciba Specialties; STRUCTURE is a trademark of National Starch & Chemical Co .; ALCOGUM is a trademark of Aleo. The amount of polymer suspension system to be used in the The dry abrasive composition according to the invention is chosen so that the viscosity of the suspension obtained on dilution with an equal amount of water is within the limits specified above. The amount is at least 0. 1% and will generally not exceed 10%. All combinations of polymer suspension and surfactant systems can be used. In particular, the stability of a suspension based on a surfactant suspension system can be further improved by additionally adding a small amount of a thickener polymer to the dry abrasive composition. Optional foaming surfactants, when not already present in a surfactant suspension system, can be chosen from anionic foaming surfactantsknown non-ionic, cationic, zwitterionic or amphoteric, which do not adversely affect the suspension system. The pH of the ready-to-use liquid abrasive cleaner should preferably be between 5 and 14. The improved cleaning properties are obtained when the pH of the cleaner is alkaline, preferably above 9 and more preferably below 1 2. The abrasive composition dry should contain, if necessary, an additional pH regulator system, such as a suitable base, to bring the pH of the liquid cleaner between the desired values. Suitable bases are, for example, alkali metal hydroxides or carbonates, ammonium carbonate, organic bases, such as triethylamine, amino-methylpropanol (AMP), aminobutanol, mono-, di- or tri-ethanolamine, monoisopropylamine or amomethylpropanediol. .

The dry abrasive compositions according to the invention may contain optional components, which improve their cleaning properties. Examples thereof are solid bleaching agents, in particular halogen halogen agents. In the latter case, the other components of the dry compositions, in particular, the surfactants and suspension system should obviously be stable to the bleach. Other examples are organic solvents, such as hydrocarbons and terpenes, alkanolamines, (poly) ethylene and (poly) propylene glycols and phenyl or C1-C6 alkyl ethers thereof. The amount of such solvents should be such that it does not interfere with the free flowing properties of the dry composition and will therefore generally be less than 6%. Additionally, the dry compositions may contain other optional components well known in the art for liquid abrasive cleaners, such as components: • to increase their attractive qualities to the consumer, such as dyes, optical brighteners and particularly perfumes; • to prevent microbial contamination or give antimicrobial properties to the product, for example, preservatives and bactericides; • to increase its handling properties, such as: agents for free flowing (stratifying agents, <10%) to prevent lumping of the dry composition (examples: Alusil ET, a porous aluminum silicate marketed by J. Crosfield , and Socal P2V, commercialized by Solvay), dispersing agents to improve an easy dispersion of the dry composition in water and / or to give the 1 suspension obtained freeze / thaw stability (examples: anionic polymers with a mol weight <100,000, STP and / or other inorganic or organic phosphonates or phosphates), defoamers to prevent excessive foaming (example: fatty acid). Free flowing agents and dispersing agents are particularly preferred additional components. The dry compositions according to the invention may have some form, which is suitable for easy dispersion in water, such as powder, granules, pellets or even tablets. The powders, granules and pellets should preferably flow freely. The processes of spray drying, fluidized bed drying, granulation and similar processes known in the art are very suitable for obtaining products, which flow freely and are easily dispersed without forming lumps. For granulation, the addition of a granulating aid, such as a polyethylene glycol with a molecular weight of 1500-4000 may be useful. The tablets can be obtained by compressing a predetermined amount of the aforementioned products. They may contain a disintegration aid to improve dispersion in water. Such disintegration aids are well known in the laundry detergent and dishwashing tablets art. The ready-to-use abrasive cleansers can be obtained from the dry compositions by adding an adequate amount of water. In general, the amount of water should be such that the liquid product contains between 10% and 65% solid abrasive, preference between 10% and 60%, more preferably between 15% and 50%, and the product has a viscosity? 2? between 0.4 and 3.0 Pas. s, preferably between 0.8 and 2.5 Pas.s, more preferably between 1.0 and 2.0 Pas. s.

Preferred compositions Preferred dry compositions containing a suspension system based on surfactant will generally have a composition as set out below: Preferred dry compositions containing a suspension system based on a polymeric thickener will generally have a composition as set out below: EXAMPLES Example 1 A solid abrasive composition, containing a suspension system based on surfactant, was prepared having the composition below: Acid LAS 5.97 Lialet 111-5.5 1) 3.13 Omyacarb 30AV 2) 79.57 Sodium carbonate 7.22 Prifac 7901 3) 0.90 Acusol 823 4) 0.036 Perfume 0.72 Proxel GXL 5) 0.028 Socal P2V 6) 1.00 0 Alusil 7) 0.75 Water 0.67 1) Nonionic surfactant of ethoxylated alcohol marketed by Condea Chimica DAC 2) Calcite marketed by Omya, average particle size claimed as 30 microns. 3) Fatty acid mixture marketed by UniQema 4) Polyacrylate marketed by Rohm & Haas 5) Conservative supplied by Zeneca Biocides 6) 7) Aluminum silicate marketed by J Crosfield The Omyacarb and sodium carbonate were heated in the bowl of a RotoJunior 1 0L high speed mixer / granulator (Zanchetta &C. S.r.l., Italy), until the temperature had reached approximately 50 ° C. LAS acid was first added, heated to 50 ° C, and allowed to be distributed throughout the solid mixture. Once dispersed, the nonionic / fatty acid / polymer / minor mixture (except free flowing agent and perfume) was added to the bowl. Both LAS acid and the non-ionic mixture were added slowly, as the stirrer was rotating (300 rpm), the time taken to add the liquids approximately 2 m inutes. Upon completion of the liquid addition, the RotoJunior run continues with the agitator, cutter (1400 rpm) and heating (65 ° C) for an additional 10 minutes. After this, the agitator and cutter are disconnected and the RotoJunior is cooled with water for 20 minutes to cool the product. Every 5 m inutes, the agitator is turned on again for a few seconds for mixing. Then the agent is added to flow freely (Socal U2) and the material is discharged. The perfume is then added externally, using a spray gun and a barrel.

Example 2 A solid abrasive composition was prepared, containing a suspension system based on polymeric thickener, having the com position below: Calcite 95 Carbopol ETD 2623 1) 0.36 Oxide of (C 16-18) alkyl-dimethylamine 0.42 AMP (2-am i no-2-m eti I-pro pan or 1-1) 0.38 NaOH 1 .00 Perfume 0.84 Ag ua , etc to 100% 1) Polyacrylate marketed by B F Goodrich.

The mixing process was carried out in a Kenwood Chef mixer using the "K" shaped attachment according to the procedure below: 1 . Add calcite to the mixing bowl 2. Add polymer powder and mix together for approximately 5 min, mixing speed is adjusted to low to medium to avoid any loss of dust. The remaining ingredients are liquids added via a pipette. 3. While mixing, add AMP pre-dispersed in approximately 1% water 4. Add NaOH (10% solution), mix for approximately 5 min 5. Add amine oxide 6. Add perfume; Mix until a satisfactory homogenous mixture is reached. Approximately 20 min.

Claims (10)

1 . A dry solid composition comprising a solid abrasive characterized in that it comprises a suspension system suitable for obtaining a stable suspension upon mixing with a liquid medium.

2. A dry abrasive composition according to claim 1, characterized in that it contains at least 65% solid abrasive and at least 0.1% suspension system.

3. A composition according to claim 2, characterized in that the amount of abrasive is at least 70%.

4. A composition according to claims 1-3, characterized in that the abrasive is insoluble in water.

5. A dry abrasive composition according to claims 1-5, characterized in that the suspension system is chosen so that the suspension obtained after mixing the dry composition with an equal amount of water has the following flow properties:? 0 is at least 2500 Pa.s sc is 2.5-25? 21 is at least 0.1 Pa.s

6. A composition according to claims 1-5, characterized in that the suspension system comprises one or more surfactants capable of forming a lamellar phase of micelles over mixed with the liquid medium.

7. A composition according to claim 6, characterized in that the surfactants comprise an anionic surfactant and a nonionic surfactant.

8. A composition according to claims 1-5, characterized in that the suspension system comprises one or more polymeric thickening agents.

9. A composition according to claims 1-8, characterized in that it comprises at least 0.1% of a foaming surfactant.

10. A composition according to claims 1-9, characterized in that it comprises an agent for free flowing and / or a dispersing agent. eleven . A composition according to claims 1-10, characterized in that it has been subjected to processing to make it flow freely and easily dispersible. 12. A composition according to claim 1, characterized in that the processing is chosen from spray drying, fluidized bed drying and granulation. 13. A process for preparing liquid abrasive cleaning compositions, comprising mixing a dry composition according to any of claims 1-12 with a liquid medium. 14. A process according to claim 1, wherein the liquid medium consists of at least 85% water. 15. A process according to claim 13 or 14, characterized in that the ratio of liquid medium to dry composition is chosen such that the liquid abrasive cleaner contains 1-0-65% solid abrasive. 16. A process according to claims 13-15, characterized because the amount of liquid medium is chosen so that the liquid abrasive cleaner has? 21 between 0.4 and 3.0 Pa.s.