DE68917763T2 - Liquid detergent. - Google Patents

Description

Technical area

The invention relates to pourable, homogeneous, aqueous, liquid cleaning agents, in particular agents containing a water-soluble particulate abrasive, which are suitable for hand-washing dishes, earthenware, cutlery and cooking pots and also for cleaning other hard surfaces such as plastic-coated work surfaces, glass and ceramic tiles.

background

Liquid detergents for cleaning hard surfaces are generally divided into two types. The first concerns aqueous suspensions containing water-insoluble, perceptible abrasive particles: sometimes difficulties arise in rinsing a hard surface cleaned with such a detergent, since insoluble particles of the abrasive are difficult to completely remove from the surface. The second type concerns liquid detergents, usually containing soap, non-ionic surfactants and alkylbenzene sulfonates, but with non-perceptible abrasive particles.

Liquid detergents of the latter type, although they do not have the potential problem of scratching during use, nevertheless suffer from numerous disadvantages that limit their acceptance by consumers. For example, they may have poor cleaning performance on stubborn dirt, particularly in areas of high water hardness, due to the absence of an abrasive component. They may also be heterogeneous and may have viscosity characteristics that are not ideal for consumer use. In addition, the higher surfactant concentration required to remove grease and greasy soils may lead to excessive foaming during use, making rinsing and wiping difficult. the consumer. Although excessive foaming can be controlled to some extent by adding a foam regulating agent such as solvent, hydrophobic silica and/or silicone or soap, this itself can give rise to problems such as poor product stability and inhomogeneity and problems associated with the deposition of insoluble residues on the objects or surfaces to be cleaned, leading to residual streaking and spotting after drying.

It has been proposed in U.S. Patent No. 4,057,506 (Colgate Palmolive Company) to use a builder salt such as a water-soluble phosphate, silicate, borate, carbonate, bicarbonate or citrate in a heavy-duty liquid detergent in such a way that the composition is substantially free of builder salt in solid particle form and the composition is otherwise smooth and creamy. However, it is an essential feature of the Colgate Palmolive composition that a builder salt in solid form is colloidal size particles having a particle size < 1 µm, usually < 0.1 µm.

It appears that builder salt particles of this size, although they may act as builders, are too small to act as an abrasive. Such compositions are therefore ineffective in cleaning heavily soiled hard surfaces because they lack abrasive power.

It has been proposed in GB-A-1 370 377 to mix water-soluble salt into a substantially non-aqueous liquid agent so that the salt remains undissolved and can act as an abrasive.

It has also been proposed in EP-A-0 193 375 (Unilever) to use a water-soluble salt such as sodium bicarbonate in the form of undissolved particles, having an average particle diameter of 10 to 500 µm, suspended in an aqueous cleaning composition which is then suitable for cleaning hard surfaces. It is envisaged that the sodium bicarbonate should be of a suitable size so that it acts as an abrasive, but the composition should have low soil redeposition and little or no tendency to causing streaking or staining on surfaces cleaned with it. This appears to be due to the ability of residual particles of sodium bicarbonate to dissolve in excess water used to rinse the cleaned surfaces.

However, experience has shown that although sodium bicarbonate, when used as described in EP-A-0 193 375, exhibits excellent cleaning performance, the agent usually feels slimy to the touch and consequently, when used for the manual washing of hard surfaces such as dishes, cutlery and cooking pots and the like, without the use of gloves, causes an unpleasant skin feeling, sufficient to cause the consumer to look for an alternative product.

Investigations have now shown that this undesirable property is due to the alkaline pH of the agent of 8.5 or higher, which is unavoidable when sodium bicarbonate is used in an amount sufficient to act as the sole water-soluble abrasive.

In our research for an alternative abrasive that has water solubility and abrasive properties similar to sodium bicarbonate, but without the unpleasant properties associated with such products, numerous substances were tested.

Finally, it was found that potassium sulfate had the required abrasive properties and water solubility and could also be readily formulated into stable products with neutral or slightly acidic pH which, surprisingly, did not exhibit any of the unpleasant and unacceptable feel characteristics associated with a similar sodium bicarbonate-containing product.

Definition of the invention

Accordingly, the invention provides a pourable, homogeneous, abrasive, aqueous cleaning composition, comprising, in addition to water:

(i) a detergent active ingredient;

ii) water-soluble salt, at least a portion of which is potassium sulfate in an amount of 2 to 65% by weight of the composition and is present in both dissolved and undissolved states, and the undissolved portion of the potassium sulfate has an average particle diameter of 10-500 µm and constitutes 0.5 to 60% by weight of the composition;

the agent having a pH of less than 8 and an apparent viscosity at 20°C of at least 6500 Pas at a shear rate of 3 x 10⁻⁵ s⁻¹ and not more than 10 Pas at a shear rate of 21 s⁻¹.

Compositions according to the invention are suitable for manual dishwashing and/or cleaning other hard surfaces. In general, the compositions are usable in both ways and, although they are not usually optimal for both applications, are thus dual-functional compositions. A composition may be formulated to be primarily a manual dishwashing product, in which case it would contain a fairly high proportion of detergent active with a low proportion of abrasive. Alternatively, a composition may be formulated to be primarily suitable for cleaning immobile hard surfaces and removing stubborn dirt, in which case it would contain a fairly high proportion of abrasive with a low proportion of detergent active.

Disclosure of the invention and embodiments thereof Detergent active compound

The agent according to the invention comprises a detergent active. It is suitably selected from synthetic anionic detergent actives and occasionally also non-ionic detergent actives.

Suitable synthetic anionic detergent active compounds are water-soluble salts of organic sulfuric acid reaction products which have in the molecular structure an alkyl radical with 8 to 22 carbon atoms and a radical selected from sulfonic acid or sulfuric acid ester radicals and mixtures thereof. Examples of synthetic anionic detergents are sodium and potassium alkyl sulfates, particularly those obtained by sulfonating higher alcohols prepared by reducing the glycerides of tallow or coconut oil; sodium and potassium alkylbenzenesulfonates, such as those in which the alkyl group contains 9 to 15 carbon atoms; sodium alkyl glyceryl ether sulfates, particularly those ethers of higher alcohols derived from tallow and coconut oil, sodium coconut oil fatty acid monoglyceride sulfates; sodium and potassium salts of sulfuric acid esters of the reaction product of one mole of a higher fatty alcohol and 1 to 6 moles of ethylene oxide; sodium and potassium salts of alkylphenol ethylene oxide ether sulfate having 1 to 8 ethylene oxide units in the molecule and in which the alkyl radicals have 4 to 14 carbon atoms; the reaction product of fatty acid esterified with isethionic acid and neutralized with sodium hydroxide, for example the fatty acids derived from coconut oil and mixtures thereof.

The preferred water-soluble synthetic anionic detergent active compounds are the ammonium and substituted ammonium (such as mono-, di- and triethanolamine), alkali metal (such as sodium and potassium), and alkaline earth metal (such as calcium and magnesium) salts of higher alkylbenzene sulfonates, higher alkyl sulfonates, higher alkyl α-olefin sulfonates, higher alkyl sulfates, higher alkyl ether sulfates, and mixtures thereof. Higher alkyl aromatic sulfonates may particularly include higher alkylbenzene sulfonates having from 6 or 8 to 20 or 22 carbon atoms in the alkyl group in a straight or branched chain.

Particularly preferred mixtures of anionic detergent actives comprise (i) sodium alkylbenzenesulfonate and sodium lauryl ether sulfate (2EO to 8EO) and (ii) sodium secondary alkylsulfonate with sodium lauryl ether sulfate.

The amount of synthetic anionic detergent active to be employed in the cleaning composition of the present invention is generally from 1 to 40%, preferably from 2 to 25%, and most preferably from 2 to 20% by weight.

Suitable non-ionic detergent active compounds can be broadly described as compounds prepared by condensation of alkylene oxide groups, which are hydrophilic in nature, with an organic hydrophobic compound, which is aliphatic or alkylaromatic in nature. The length of the hydrophilic or polyoxyalkylene moiety condensed with a particular hydrophobic group can be readily adjusted to obtain a water-soluble compound having a desired degree of balance between hydrophilic and hydrophobic elements.

Particular examples are the condensation product of aliphatic alcohols having 8 to 22 carbon atoms in straight or branched chain configuration with ethylene oxide, such as a coconut oil ethylene oxide condensate having 2 to 15 moles ethylene oxide per mole of coconut oil; condensates of alkylphenols, the alkyl group of which contains 6 to 12 carbon atoms with 5 to 25 moles ethylene oxide per mole of alkylphenol; condensates of the reaction product of ethylenediamine and propylene oxide with ethylene oxide, condensates containing 40 to 80% polyoxyethylene residues by weight and having a molecular weight of 5,000 to 11,000; tertiary amine oxides of the structure R₃PO, where one group R represents an alkyl group having 8 to 18 carbon atoms and the others each represent methyl, ethyl or hydroxyethyl groups, for example dimethyldodecylamine oxide; tertiary phosphine oxides of the structure R₃PO, where one group R represents an alkyl group having 10 to 18 carbon atoms and the others each represent alkyl or hydroxyalkyl groups having 1 to 3 carbon atoms, for example dimethyldodecylphosphine oxide; and dialkyl sulfoxides of the structure R₂SO, where the group R represents an alkyl group having 10 to 18 carbon atoms and the other represents methyl or ethyl, for example methyltetradecyl sulfoxide; fatty acid alkylolamides; alkylene oxide condensates of fatty acid alkylolamides and alkyl mercaptans.

Mixtures of two or more non-ionic detergent active ingredients can be used in the cleaning agent according to the invention.

The amount of non-ionic detergent active ingredient, which can optionally be used in the cleaning agent according to the invention is generally 0.5 to 15%, preferably 1 to 10%, most preferably 1 to 8% by weight.

When both anionic and non-ionic detergent actives are used, the weight ratio of anionic detergent active to non-ionic detergent active may vary, but is preferably in the range of 1:9 to 9:1, ideally 1:4 to 4:1.

Preferably, the compositions contain an amount of both anionic and nonionic detergent active selected to provide a structured liquid detergent composition, i.e. one which is self-thickening without the use of an actual thickener.

According to one embodiment illustrating this aspect of the invention, the detergent will comprise 2 to 16% by weight of a water-soluble synthetic anionic sulfated or sulfonated detergent salt having an alkyl radical of 8 to 22 carbon atoms in the molecule and 0.5 to 4% by weight of an alkyleneoxylated nonionic detergent derived from the condensation of an aliphatic alcohol having 8 to 22 carbon atoms in the molecule and ethylene oxide such that the condensate has 2 to 15 moles of ethylene oxide per mole of aliphatic alcohol.

It is also possible to optionally include amphoteric, cationic or zwitterionic detergent active ingredients in the agents according to the invention.

Suitable amphoteric detergent active compounds which may optionally be employed are derivatives of aliphatic, secondary or tertiary amines having an alkyl group of 8 to 18 carbon atoms and an aliphatic radical substituted with an anionic water-soluble group, for example sodium 3-dodecylaminopropionate, sodium 3-dodecylaminopropanesulfonate and sodium N-2-hydroxydodecyl-N-methyltaurate.

Suitable cationic detergent active compounds are quaternary ammonium salts with an aliphatic residue of 8 to 18 carbon atoms, for example cetyltrimethylammonium bromide.

Suitable zwitterionic detergent active compounds which may optionally be employed are derivatives of aliphatic quaternary ammonium, sulfonium and phosphonium compounds having an aliphatic radical of 8 to 18 carbon atoms and an aliphatic radical substituted with an anionic water-solubilizing group, for example 3-(N,N-dimethyl-N-hexadecylammonium)-propane-1-sulfonate betaine, 3-(dodecylmethylsulfonium)propane-1-sulfonate betaine and 3-(cetylmethylphosphonium)ethanesulfonate betaine.

Further examples of suitable detergent active compounds are compounds commonly used as surface active agents, given in the well-known textbooks "Surface Active Agents", Vol. I by Schwartz and Perry and "Surface Active Agents and Detergents", Vol. II by Schwartz, Perry and Berch.

The total amount of detergent active compound to be used in the cleaning agent according to the invention is generally from 1 to 40%, preferably from 1.5 to 30%, more preferably from 2 to 20 or 25% by weight.

The water-soluble salt

The composition according to the invention also contains at least one water-soluble salt, namely potassium sulfate, which serves as an abrasive agent. This salt can be present in the composition in an amount in excess of its saturation solubility and thus exists in both the dissolved and undissolved state. The composition therefore comprises a saturated aqueous solution of potassium sulfate together with 0.5 to 60%, preferably 1 to 50% by weight of the composition at 20°C in the form of a solid phase comprising particles of the salt having an average particle diameter of 10 to 500 µm, preferably 20 to 300 µm, providing the required abrasive properties.

The water-soluble potassium sulfate salt is anhydrous and does not change to a hydrated species when present as a crystalline solid in water at a temperature of 10 to 40ºC in an amount in excess of that which required for a saturated solution. The saturation solubility of the salt in water at 40ºC is less than twice that at 10ºC. These properties help to ensure that the properties of the product, particularly the size, shape and quantity of the crystalline abrasive particles, do not change over the normal application temperature range. Uniformity of performance is thus assured. These properties of potassium sulphate also help to ensure that when the agent itself is structured - ie the structure providing the desired viscosity properties is derived from an appropriate choice of anionic detergent ingredient(s) or anionic and nonionic detergent active(s) - it remains stable without significant change in viscosity.

The water-soluble salt potassium sulfate has a Mohs hardness of about 3, which provides suitable abrasive properties. It has a saturation solubility in water not exceeding 15% by weight at 10ºC, so that this allows the presence of undissolved particles at reasonable total inclusion levels.

The salt also has a solubility in water of more than 5 g/l at 10ºC, which ensures that excess salt can be easily removed from a hard surface after cleaning with the agent. In this way, the surface can be freed from residual stains or streaks.

The total amount of potassium sulfate present in the cleaning composition in both dissolved and undissolved states is from 2 to 65%, preferably from 4 to 55%, ideally from 7 to 50% by weight. From 0.5 to 60%, more preferably from 1 to 50% by weight of the water-soluble salt should be present in the composition in a solid, particulate form having an average particle size and other properties as defined herein at normal storage or use temperatures of from 10 to 40°C.

In addition to potassium sulfate, the agent according to the invention may optionally also contain other water-soluble salts, such as sodium bicarbonate, sodium chloride, potassium chloride, magnesium chloride, calcium chloride, sodium tripolyphosphate pentahydrate, sodium tetraborate decahydrate and sodium citrate, provided that the pH of the composition does not exceed 8. With this proviso it is also possible to employ other water-soluble inorganic salts or organic salts of lithium, magnesium, sodium, potassium and calcium, the salts possibly serving as builders for the abrasive. Specific examples are sodium oxalate, sodium succinate, sodium adipate and sodium glutarate. Mixtures of such salts may be used. The presence of electrolytes capable of slightly lowering the solubility of potassium sulfate in water is preferred. Particularly suitable in this respect is the addition of an alkali metal chloride, preferably sodium chloride, in an amount of 0.5 to 5% or more up to 10% of the composition. This causes a slight reduction in the solubility of potassium sulfate in water, thereby reducing the amount of potassium sulfate required to obtain a sufficient amount of undissolved particles, but at the same time does not reduce the solubility of potassium sulfate below a level of 5 g/l, thereby ensuring that excess salt can be easily removed from a hard surface after cleaning.

The presence of electrolytes, especially sodium chloride, is also beneficial as it improves the freeze-thaw stability of the product.

A particular advantage is the addition of an additional electrolyte in addition to the alkali metal chlorides, where this additional electrolyte is preferably an alkali metal citrate, such as sodium citrate, which provides an additional benefit of pH regulation.

It is preferred that the total amount of water-soluble salt, including potassium sulfate, is at least 9% by weight of the composition. It may be in the range of 9 to 50% by weight.

Water

The agent according to the invention may also comprise water, which generally constitutes 30 to 89.5%, preferably 40 to 80% and ideally 45 to 70% by weight of the agent.

Components present, if any

The composition of the invention may contain other ingredients that assist in cleaning performance, provided that due to the presence of these other ingredients, the pH of the composition does not exceed 8. For example, the composition may contain detergent builders such as nitrilotriacetate, polycarboxylates, citrates, dicarboxylic acids, water-soluble phosphates, particularly polyphosphates, mixtures of o- and pyrophosphates, and mixtures thereof. Such builders may additionally serve as scouring agents if present in an amount in excess of their solubility in the total composition as explained herein. In general, the builder, if employed, preferably constitutes from 0.1 to 25% by weight of the composition.

Metal ion sequestrants such as ethylenediaminetetraacetates, aminopolyphosphonates (DEQUEST) and phosphates and numerous other polyfunctional organic acids and salts may also be used if appropriate.

Another optional ingredient of the compositions of the invention is a foam control agent which can be used in compositions of the invention which tend to produce excessive foam during use. An example of a foam control agent is soap. Soaps are salts of fatty acids and include alkali metal soaps such as sodium, potassium, ammonium and alkanolammonium salts of higher fatty acids having from about 8 to about 24 carbon atoms, preferably from about 10 to about 20 carbon atoms. Particularly suitable are sodium and potassium and mono-, di- and triethanolamine salts of mixtures of fatty acids derived from coconut oil and peanut oil. If used, the amount of soap can be at least 0.005%, preferably 0.5 to 2% by weight of the composition. Another example of a foam regulating agent is an organic solvent, hydrophobic silica and a silicone oil or hydrocarbons.

The agents according to the invention can be used to assist in providing suitable rheological properties while maintaining uniform distribution of the undissolved salt or salts in the composition and better distribution and adhesion of the composition to the hard surface to be cleaned, optionally structuring agents. Preferred structuring agents are polysaccharides such as sodium carboxymethylcellulose and other chemically modified cellulosic materials, xanthan gum and other non-flocculating structuring agents such as biopolymer PS87 mentioned in US Patent No. 4,329,448. Certain polymers such as a polymer of acrylic acid cross-linked with a polyfunctional agent, for example CARBOPOL, may also be used as structuring agents. The amount of such structuring agents, if used, to be employed in the compositions of the invention may be as low as 0.001%, preferably at least 0.01% by weight of the composition.

The agents according to the invention can also comprise at least one partially esterified resin, such as an at least partially esterified adduct of natural resin and an unsaturated dicarboxylic acid or anhydride or an at least partially esterified derivative of copolymerization products of monounsaturated, aliphatic, cycloaliphatic or aromatic monomers without carboxylic acid groups and unsaturated dicarboxylic acids or anhydrides thereof.

Typical examples of suitable copolymers of the latter type are copolymers of ethylene, styrene, vinyl methyl ether with maleic acid, fumaric acid, itaconic acid, citraconic acid and the like and the anhydrides thereof. Styrene/maleic anhydride copolymers are preferred.

In general, the compositions according to the invention may optionally comprise 0.005 to 20%, usually 0.1 to 15%, preferably 0.5 to 10% by weight of the at least partially esterified resin.

Agents according to the invention may also contain, in addition to the ingredients already mentioned, other optionally present ingredients such as pH regulators, perfumes, colorants, optical brighteners, soil suspending agents, washing enzymes, compatible bleaching agents, gel-regulating agents, freeze-thaw stabilizers, bactericides, preservatives, detergent hydrotropic agents, opacifiers and solvents.

The agents according to the invention contain not more than 10%, preferably not more than 5% by weight of water-insoluble abrasive, such as feldspar and quartz, in view of the tendency of such abrasives to leave deposits on hard surfaces after cleaning, even when rinsed off with water.

Ideally, the agents according to the invention are free of water-insoluble abrasives.

In general, water and optional ingredients containing other washing aids make up the composition after adding the detergent compound and the water-soluble salt components. Consequently, water and optional ingredients can make up 89.5 to 25% by weight of the composition.

PH value

It is an important feature of the present invention that the compositions are formulated such that the pH does not exceed 8. Preferably, the compositions have a pH of 5 to 8, ideally about pH 6-7, although pH values below 3 are acceptable.

Suspending properties

It is an important feature of the present invention that the composition is capable of suspending undissolved particles of salt abrasives so that the user does not need to agitate the composition, for example by shaking, to suspend and disperse settled particles prior to use. For this reason, the composition should have an apparent viscosity at 20°C of at least 6500 Pas at a shear rate of 3 x 10-5 s-1 to ensure that the particles of the abrasive do not sediment more than 1 cm in one month on standing at 20°C. Ideally, the apparent viscosity at 20°C is at least 25,000 Pas at a shear rate of 3 x 10-5 s-1.

This viscosity value can be determined by applying Stokes' law, assuming that the particles of the abrasive are spherical and that the sedimentation rate mentioned above applies.

Although it is necessary that the composition of the invention certainly have an apparent viscosity high enough to prevent substantial settling of undissolved particles of salt abrasives during storage, it should remain liquid so that it can be easily poured from a bottle or other container when in use. For this purpose the composition should have an apparent viscosity at 20°C, measured using a rotary viscometer, of not more than 10 Pas at a shear rate of 21 s⁻¹. Preferably the apparent viscosity at 20°C is not more than 5 Pas at a shear rate of 21 s⁻¹.

Appropriate rheological conditions to satisfy these criteria can be provided by careful selection of anionic and nonionic detergents to provide a structured liquid with the required suspending properties and/or by using an appropriate amount of an alternative structuring agent as described herein.

A preferred method for adjusting the viscosity of the agent is the inclusion of a water-soluble polymer in the system, for example as described in our co-pending application EP 88 307 007.0.

Process for preparing the agent

Since the agents according to the invention are in liquid form, they can be prepared simply by mixing the essential and optionally present ingredients.

Packaging and use of funds

The agents according to the invention are pourable liquids which are preferably stored in a closed container for Storage, transportation and sale must be kept without spillage.

The products are particularly suitable for the manual washing of dishes, cutlery, cooking pots and other utensils and for cleaning dirty hard surfaces such as those found in domestic kitchens and bathrooms. The products can be used undiluted, i.e. without dilution, or they can be first diluted with water as required, before application to the dirty surface, for example with a cloth, brush or sponge for easier application. After application, any excess undissolved water-soluble salt abrasive remaining on the surface can be easily removed by rinsing with clean water in which it is dissolved.

Surfaces cleaned in this way with the agent according to the invention show a lower tendency to form residual streaks or stains than surfaces that have been cleaned with corresponding products that contain water-insoluble abrasives such as calcite.

Examples

The invention is illustrated by the following examples and formulations. Percentages are by weight unless otherwise indicated and the undissolved potassium sulfate in each example has an average particle size of about 150 µm. The formulations all have sufficient suspending properties with a viscosity in excess of 6500 Pas at a shear rate of 3 x 10-5 s-1. Adjustment of the pH was carried out using sodium hydroxide solution or sulfuric acid, if necessary.

example 1

This example illustrates the formulation of a concentrated agent according to the invention for manual dishwashing.

The formulation of this detergent concentrate was as follows:

% wt/wt

Sodium alkylbenzenesulfonate 3.0

Sodium lauryl ether sulfate (3EO) 4.5

Coconut diethanolamide 7.5

Potassium sulfate 20.0

Perfume 0.25

Water --- Fill to 100% ---

The viscosity at 20°C was 0.8 Pas at a shear rate of 21 s⁻¹ and > 6500 Pas at a shear rate of 3 x 10⁻⁵ s⁻¹.

The pH was adjusted to 7 with sodium hydroxide or sulfuric acid. The undissolved potassium sulfate particles were present in an amount of about 10%.

Example 2

A formulation for manual dishwashing was formulated as follows:

% wt/wt

linear sodium alkylbenzenesulfonate 2.7

Sodium lauryl ether sulfate (3EO) 10.8

Coconut diethanolamide 4.5

Potassium sulfate 8.0

Sodium chloride 2.0

Trisodium citrate 2H₂O 0.5

Perfume 0.25

Water --- Fill to 100% ---

The viscosity at 20ºC: 0.6 Pas at a shear rate of 21 s⊃min;¹.

Undissolved potassium sulfate particles: 2 %

The pH was adjusted to 6 with sodium hydroxide or sulfuric acid.

Example 3

A product for manual dishwashing was formulated as below:

% wt/wt

linear sodium alkylbenzenesulfonate 2.7

Sodium lauryl ether sulfate (3EO) 10.8

Coconut diethanolamide 4.5

Potassium sulfate 12.0

Sodium chloride 2.0

Trisodium citrate 2H₂O 0.5

Sodium polyacrylate (MW about 4000) 0.2

Perfume 0.2

Water --- Fill to 100% ---

Viscosity at 25ºC: 0.35 Pas at 21 s⊃min;¹.

Undissolved potassium sulfate particles: about 6%

The pH was adjusted to 6 with sodium hydroxide or sulfuric acid.

Example 4

A product for manual dishwashing was formulated as below:

% wt/wt

secondary sodium alkylbenzenesulfonate 3, 6

Sodium lauryl ether sulfate 14.4

Potassium sulfate 12.0

Sodium chloride 6.0

Perfume 0.2

Water --- Fill to 100% ---

pH = 6. Viscosity at 25ºC: 0.71 Pas at 21 s-1.

Undissolved potassium sulfate particles: about 8%

Example 5

A hard surface cleaning product has been formulated as follows:

% wt/wt

linear sodium alkylbenzenesulfonate 1.8

Sodium lauryl ether sulfate (3EO) 10.4

Potassium sulfate 40.0

Sodium chloride 2.0

Trisodium citrate 2H₂O 0.3

Perfume 0.2

Water --- Fill to 100% ---

pH = 6.5. Viscosity at 25ºC: 0.96 Pas at 21 s-1.

Undissolved potassium sulfate particles: about 35%

Example 6

A product for manual dishwashing was formulated as below:

% wt/wt

linear sodium alkylbenzenesulfonate 3.8

Sodium lauryl ether sulfate (3EO) 15.0

Coconut diethanolamide 6.2

Potassium sulfate 12.0

Sodium chloride 1.7

Trisodium citrate 2H₂O 0.4

Perfume 0.2

Water --- Fill to 100% ---

pH = 7. Viscosity at 25ºC: 2.1 Pas at 21 s-1 at 25ºC.

Undissolved potassium sulfate particles: about 5%

Claims (10)

Patent claims 1. Pourable, homogeneous, abrasive, aqueous cleaning agent comprising, in addition to water: (i) a detergent active ingredient; ii) water-soluble salt, at least a portion of which is potassium sulfate in an amount of 2 to 65% by weight of the composition and is present in both dissolved and undissolved states, and the undissolved portion of the potassium sulfate has an average particle diameter of 10-500 µm and constitutes 0.5 to 60% by weight of the composition; the agent having a pH of less than 8 and an apparent viscosity at 20°C of at least 6500 Pas at a shear rate of 3 x 10⁻⁵ s⁻¹ and not more than 10 Pas at a shear rate of 21 s⁻¹. 2. A composition according to claim 1, wherein the amount of detergent active ingredient is at least 1.5% by weight of the composition, the amount of water-soluble salt is at least 9% by weight of the composition and the amount of potassium sulfate is at least 2% of the composition. 3. Agent according to claim 2, wherein the amount of detergent active ingredient is 1.5 to 40% by weight of the agent. 4. A composition according to claim 2, wherein the amount of detergent active ingredient is 1.5 to 30% by weight of the composition and the amount of water-soluble salt is 9 to 50% by weight of the composition. 5. A composition according to any one of the preceding claims, wherein the water-soluble salt includes at least one electrolyte capable of reducing the solubility of potassium sulfate. 6. A composition according to claim 5, wherein the electrolyte comprises alkali metal chloride in an amount of 0.5 to 10% by weight of the composition. 7. Agent according to one of the preceding claims, wherein the anionic detergent active ingredient makes up 1 to 25% by weight of the agent. 8. Agent according to claim 7, wherein the non-ionic detergent active ingredient makes up 0.5 to 15% by weight of the agent and the weight ratio of anionic to non-ionic detergent active ingredient is 1:9 to 9:1. 9. A composition according to any preceding claim, wherein the undissolved potassium sulfate has an average particle diameter of 20 to 300 µm. 10. A composition according to any preceding claim, wherein water makes up 30 to 89.5% by weight of the composition.