SK103895A3 - Detergent composition - Google Patents

Abstract

A detergent composition which gives a softening benefit in the wash. The detergent composition contains at least one detergent active material, a fabric softening clay which is a bentonite clay and at least 1 wt % of the total formulation, of a soluble potassium salt, expressed as K2O.

Description

Technical field

The invention relates to detergent compositions for washing and softening fabrics comprising at least one detergent active material and bentonite clay softening fabrics. The invention also relates to a method for producing clay.

BACKGROUND OF THE INVENTION

In some fabrics, especially of natural origin, repeated washing can lead to roughening of the fabric, giving the fabric an unpleasant feel. For some years, fabric conditioners have been available, intended, inter alia, to alleviate this roughening of the fabric by softening the fabrics in the post-wash step, for example, in the rinse step of the fabric wash process. Simple detergent compositions have also been provided which are capable of both washing and softening fabrics, thus overcoming the disadvantage of using separate products.

According to British Patent GB 1,400,898 (Procter & Gamble / STORM), such a simple detergent and softener composition is provided by adding to the detergent composition together with a detergent material a material containing smectic clay having a cation exchange capacity of at least 50 mmol / ml. 100 g.

GB 2,138,037 discloses a fabric softening detergent in which clay can be activated by incorporating a monovalent metal into the clay structure. Sodium and potassium ions are given as examples of monovalent ions.

Although some success has been achieved with the use of such clay materials, the softening efficiency has not yet achieved the efficiency obtained using separate products, and there is therefore an area for improving efficiency.

The clays to which this invention relates are of the swellable type, which expand and delaminate in a liquid medium.

These clays belong to the group of phyllosilicates and are crystalline materials of the three-layer leaf type. The sheet structure is formed from a three-layered arrangement of tetrahedral silica, octahedral alumina and tetrahedral silica. The middle layer may be dioctaedric or trioctaedric, and the three-layered leaf structures are separated by an interlamellar space.

The clays are defined as crystalline or amorphous hydrated silicates Al, Mg, Li and Fe. They contain fine colloidal particles. The following key features distinguish different types of clay:

(a) chemical composition;

(b) degree of isomorphic substitution (replacement of one working ion with another ion of similar size, usually with another valence).

Point b) offers the possibility of a permanent charge on the grid, which must be in balance with the cations present in close proximity. These properties can be clearly illustrated with reference to talc and hectorite (magnesium silicate) and pyrophyllite and montmorillonite (aluminosilicates); details are given in Table 1:

Table 1:

Hlinka Isomorphic substitution formula talc not S3 ^Si 4 ° 10 < ^0H > 2 hectorite Yes _{^<M), and} (Mg) _{and 6} (Li) _and Si ₈ O ₂₀ (OH) ₄ pyrophyllite not Al ₂ Si ₄ O ₁₀ ( ^OH ) 2 montmorillonite Yes (M ⁺ ) _and (Al) ₄ . _and (Mg) _and Si ₈ O ₂ '(OH) ₄

In this table, M ⁺ denotes charge-leveling cations induced as a result of isomorphic substitution. The degree of isomorphic substitution determines the charge charge of the layer, a critical factor for the swelling of clay.

The nature of the layer structure has several variants. For example, the middle octahedral layer may have two aluminum ions (dioctaedric) replaced by three magnesium ions (trioctaedric) or the octahedral layer may be (Al ³⁺ ) (Mg ²⁺ )

3+ 94 partially occupied by replacing one Al with one Mg (di9 * 4 ok octaedric) or one Mg with Li (trioctaedric), which causes an excessive negative charge in the structure. The residual excess negative charge may also arise when silicon ions (Si ⁴⁺ ) in the tetrahedral layer are replaced by aluminum ions (Al ³⁺ ).

Excessive negative charge requires the presence of balancing cations which are located in the interlamellar space between the slat structures. The degree of excess negative charge is given by the number of exchangeable cations, which corresponds to the cation exchange capacity of the pure mineral CEC. The mineral CEC is directly related to the grid charge deficit of this mineral.

This can be further explained by the general notion of clays useful for the present invention, which fall under the formulas: (Si ₄ - _y Al _y ) (M ^III aN ^II b) O ₁₀ (OH) ₂ X ^{n +} (y + b) / n clay) or:

(Si ₄ _ _y Al _y ) (N ^{II a} L ^I b) 0 _1Q (OH) ₂ X ^{n +} (- _{y + b} ) / _n (trioctaedric clays), where X ^{n +} is a balancing replaceable cation, which may be monovalent or divalent , y + b is the deficiency of the lattice charge of the mineral per half of the unit cell,

III

II is a trivalent metal ion, e.g. Al is a divalent metal ion, e.g. Mg

3+

2+

Zn

2+

fe

3+

fe

2+

Cr +

Ni ²⁺ .

is a monovalent metal ion, for example Li ⁺ , y is 0 or a positive number less than four, and b and b are, separately or together, zeroes or positive numbers.

CEC measurements indirectly determine the number of X ^{n +} y + b / _n at 100 g and are reported in mmol of monovalent ion.

Thus, the value of y + b (lattice charge deficit) in gram equivalents per half of the unit cell is directly bound to CEC.

Swelling is a process in which solvent molecules penetrate into the inner interlayer space between individual crystals and occurs very easily with clays that contain exchangeable cations such as hectorites and montmorillonites. The factors most influencing the swelling behavior in an aqueous suspension are:

i) origin of the layer charge - i. whether the substitution is in an octahedral (Mg or Al) layer, or a tetrahedral (Si) layer;

(ii) the charge level of the layer; and iii) a type of interlayer cation.

Point (i) is important because the substitution in the tetrahedral layer forms a localized charge and in the octahedral layer forms a delocalized charge. The latter interacts poorly with water molecules.

The clay used to soften fabrics during laundering is generally montmorillonites. Although the softening efficiency has been shown to be a function of the grid charge, the detailed mechanism of action of clays to soften fabrics is not fully understood. Both the delamination (swelling) behavior and the electrostatic forces between the clay particles and the fabric substrate are considered to control the overall process and both are influenced by the layer charge.

Montmorillonites occur in nature with different charge range ranges and optimal softening has been observed with a limited number of weakly colored clays having layer charges at the lower end of the range. However, the charge of the clay grid can be modified by chemical treatment. The controlled incorporation of Li ⁺ cations into the crystal lattice (by ion exchange / calcination) is described in EP 0 401 047 (Unilever) and results in improved clay efficiency through charge reduction.

Reducing the charge of the montmorillonite layer requires neutralizing the delocalized negative charge. This is considered achieved when Li ⁺ cations penetrate the crystal lattice upon dehydration. They are believed to move into octahedral vacancies in the aluminum region of the montmorillonite lattice. The process requires an expensive calcination step to achieve dehydration of the Li ⁺ cation before penetration into the grid.

Soil scientists know the close connection of some cations to clay surfaces and call it cation-fixation. The most studied ion is potassium; its ion diameter is close to the circle diameter of the six oxygen atoms characteristic of the crystal surfaces of the clay. Logically, therefore, good coordination of potassium with the clay surface can be expected.

EP 0 401 047 discloses a clay mineral fabric softening which is a dioctaedric 2: 1 layered phyllosilicate containing at least 100 micrograms of lithium per gram of clay mineral. In this document, they believe that K ⁺ may be a balancing replaceable cation in clay.

It is known to exchange K ⁺ in clays in the field of petroleum engineering. For example, KCl or KOH have been used as electrolytes in drilling fluids to stabilize montmorillonite or other smectic clays during drilling operations. Potassium is also a natural component of some natural bentonite clays with levels up to 1% by weight, such as.

Potassium has also been used with bentonite clay, preferably being present in small amounts in sodium salts when prepared commercially. The potassium level in this case should be less than 1% by weight, expressed as K 2 O, of the total clay.

The number and availability of naturally occurring clays is rather limited. Such naturally occurring clays may be unsuitable for incorporation into the detergent composition or may cause the color of the fabric to become obscured if it is trapped thereon. It is therefore desirable to increase the softening efficiency achieved for low-efficiency, naturally occurring clays of good color, as well as extending the range of clays that can be used to soften fabrics.

It has now been found that such an increase in efficacy can be achieved if the bentonite clay is treated with potassium. It has also been found that this treatment can be carried out either before the clay is incorporated into the detergent composition or by ion exchange during the washing process.

SUMMARY OF THE INVENTION

The present invention provides a fabric laundering and softening detergent composition comprising at least one detergent active material, fabric softening clay which is bentonite clay and at least 1% by weight of the total soluble potassium salt formulation, expressed as K 2 O.

The invention also provides a detergent composition for washing and softening fabrics comprising at least one detergent active material and potassium exchanged bentonite clay, wherein the level of potassium in the clay is more than 1.5% by weight expressed as K 2 O.

Such potassium treated clays have the advantage that they can be selected from a wide range of good color clays. Detergent compositions containing modified clays have the advantage that the blurring of the paint associated with clay of the unsuitable color can be avoided and improved softening can be obtained.

One aspect of the process of the present invention involves the preparation of clays with partially exchanged potassium. They can be prepared by mixing dry sodium clay with a solution containing potassium ions, typically with a KCl solution to form a dense dough. The dough is then subjected to a high shear in a sigma knife mixer and then dried and crushed.

They may also be prepared by spraying sodium clay with a potassium solution in a rotating drum, for example in an agglomerating apparatus.

Alternatively, the following may be prepared:

(i) mixing the aqueous dilute suspension of fully potassium and fully sodium exchanged clay in suitable proportions; or (ii) performing an ion exchange clay in a mixed sodium / potassium medium.

Preferably, the mixtures of sodium and potassium clay minerals are in a ratio ranging from 8: 2 to 2: 8 parts by weight. If the ion exchange is carried out in solution before the detergent is prepared, then it is desirable to dry the clay.

It is preferred that the ratio of sodium to potassium exchanged clay is less than 2: 1, preferably less than 1: 1.

Surprisingly, it has been found that, as an alternative to the ion exchange of potassium into clay before being incorporated into the detergent composition, it is also effective to prepare it with ion-exchanged or partially exchanged clay and provide a source of potassium ions for exchange during washing. Preferably, the potassium ion source is provided by partially or totally replacing the sodium salt normally present in the detergent composition with the corresponding potassium salt. It is preferred that the corresponding potassium salt is present with a content level greater than 2.5% by weight of the total composition, more preferably a level greater than 5% by weight, most preferably a level greater than 7.5% by weight.

As a source of potassium ions, potassium carbonate may be included in the formulation instead of conventional sodium carbonate, a second example of this technique being the replacement of sodium citrate with potassium citrate.

It is also advantageous to include a potassium base, for example potassium hydroxide, in the mixture, which can supply potassium ions and also neutralize any acid in the mixture, for example citric acid.

The clay mineral containing materials useful in the present invention include dioctaedric and trioctaedric three-layer smectic clays, preferably of the calcium and / or sodium montmorillonite type. For example, PRASSA clay from Greece, GELVHITE from Texas, USA, Villemse from South Africa, and VOLCLAY BC from Vyoming. The effectiveness of the clay-containing material as fabric softener will depend in part on the level of clay mineral content in the material.

The detergent compositions of the present invention may take various physical forms and may contain various additional ingredients.

The essential component is a surfactant. It may be selected from anionic, nonionic, amphoteric, zwitterionic and cationic substances, with particular preference to synthetic anionic surfactants, with or without nonionic surfactants.

Particularly preferred are mixtures of anionic and non-ionic surfactants, such as a mixture of an alkali metal salt of an alkylbenzene sulfonate with an alkoxylated alcohol. The level of surfactant (s) in the composition may be from 2 wt% to 50 wt%, most preferably from 5 wt% to 30 wt%.

In some formulations, it is preferred to have at least 25% by weight of the anionic surfactant in the composition.

Preferred surfactants which can be used are synthetic anionic and nonionic compounds. The first are usually water-soluble alkali metal salts of organic sulfates and sulfonates having alkyl radicals containing from about 8 to about 22 carbon atoms, the term alkyl being used to include the alkyl moiety of the higher acyl radicals. Examples of suitable synthetic anionic surfactants are the sodium and potassium alkyl sulfates, especially alkyl sulphates obtained by sulphating higher (Cg-C ^ g) alcohols produced for example from tallow or coconut oil, sodium and potassium alkyl ^(Cg-C 2o) benzene sulphonates, particularly sodium linear secondary alkyl (C 1 -C 6) benzenesulfonates; sodium alkyl glyceryl ether sulfates, in particular such ethers of higher alcohols, derived from tallow and coconut oil and from synthetic alcohols derived from petroleum; sodium coconut fatty monoglyceride sulfates and sulfonates; the reaction products of sodium and potassium salts of sulfuric acid esters with higher (C8-C18) fatty alcohol and alkylene oxides, in particular ethylene oxide; fatty acid reaction products, such as fatty coconut acids, esterified with isethionic acid and neutralized with sodium hydroxide; sodium and potassium salts of methyl taurine fatty acid amides; alkane.

monosulfates, such as monosulfates obtained by reacting alpha-olefins (Cg-C ₂ Q) with sodium bisulphite and those derived by reacting paraffins with S0 ₂ and CI ₂ and then hydrolysing with a base to form a random sulfonate; and olefin sulfonates, this term is used to describe materials made by reacting olefins, in particular 1010- ^20 ^and 1 l ^a -olefins, with SOg and then neutralizing and hydrolyzing the reaction product. Preferred anionic detergent compounds are sodium (C1-C6) alkylbenzenesulfonates and sodium (C1-C6) alkyl sulfates.

Suitable nonionic surfactants which can be used include, in particular, the reaction products of substances having a hydrophobic group and a reactive hydrogen atom, for example aliphatic alcohols, acids, amides or alkylphenols, with alkylene oxides, especially ethylene oxide, either alone or with propylene oxide. The specific nonionic surfactant detergent compounds are alkyl _(Cg-C22) phenols-ethylene oxide condensates, generally up to 25 EO, ie up to 25 units of ethylene oxide per molecule, the condensation products of aliphatic (Cg-C ^ g) primary or secondary linear or branched alcohols with ethylene oxide, generally up to 40 PE, and products made by condensation of ethylene oxide with the reaction products of propylene oxide and ethylenediamine. Other so-called nonionic detergents include long chain tertiary amine oxides, long chain tertiary phosphine oxides and dialkyl sulfoxides.

Detergent compositions can be used in detergent compositions, for example, mixed anionic or mixed anionic and nonionic materials, particularly in the latter case to provide controlled low foaming properties. This is advantageous for compositions intended for use in non-foam-proof automatic washing machines.

Many of the amphoteric or zwitterionic surfactants may also be used in the compositions of the present invention, but these are not normally desirable due to their relatively high cost. If any amphoteric or zwitterionic surfactants are used, they are generally in small amounts in compositions based on the much more common synthetic anionic and / or nonionic surfactants.

Detergent ingredients may also be present. These may be any substances suitable for reducing the level of free calcium ions in the wash liquid and will preferably provide mixtures with other beneficial properties, such as generating an alkaline pH, suspending the dirt removed from the fabric, and suspending the clay material to soften the fabric. The level of detergent builders may be from 10% to 70% by weight, most preferably from 25% to 50% by weight.

Examples of detergent builders include precipitants such as alkali metal carbonates (with or without seed crystals such as limestone), bicarbonates, orthophosphates, sequestering components such as alkali metal tripolyphosphates or nitrilotriacetates, or ion exchange components such as amorphous alkali metal aluminosilicates or zeolites.

The clay material can be added in various physical forms. For example, it may be sprayed-dried with other formulation components or added separately. In the latter case, the clay may be milled to a suitable size, 5 to 2000 µm, or it may be in the form of granulated fine particles optionally containing a binder, such as an inorganic salt or a surfactant.

The level of the fabric softening clay material in the composition should be sufficient to provide a softening effect, for example from 1.5 wt% to 35 wt%, most preferably from 4 wt% to 15 wt%, based on the clay material alone.

In addition to the surfactant, the detergent component and the clay-containing material, the compositions of the present invention optionally contain other ingredients.

Apart from the ingredients already mentioned, the detergent compositions of the present invention may contain any conventional additives in amounts in which such additives are normally used in fabric laundry detergent compositions. Examples of such additives include other fabric softening agents, such as cationic fabric softening agents or fatty amines. Other examples of such additions include foam enhancers such as alkanolamides, especially monoethanolamides derived from palm kernel fatty acids and coconut fatty acids, suds suppressors, oxygen-releasing bleaching agents such as sodium perborate and sodium percarbonate, peroxyacid bleach precursors, bleaching bleaching agents such as trichloroisocyanuric acid, inorganic salts such as sodium sulfate, other fillers such as kaolin, and substances usually present in minor amounts, fluorescent reagents, perfumes, other enzymes such as proteases, lipases and amylases, germicides and dyes.

DETAILED DESCRIPTION OF THE INVENTION

The invention will be further illustrated by the following non-limiting examples.

Example 1 - Preparation of ion-exchanged clay

Potassium-exchanged clay and ammonium-exchanged clay were prepared for comparative purposes by the following method. The montmorillonite used was PRASSA ex Colin Steward Minerals. Potassium acetate (anhydrous ex Sigma) was added without further drying. Ammonium, sodium and potassium salts were all from BDH GPR and solutions of desired concentration were prepared using Millipore purified water.

150 ml of a 0.1 M KCl or NH 4 Cl solution was added to the montmorillonite suspension (approximately 20 g in 500 ml). The mixture was stirred overnight and then centrifuged and washed repeatedly with water until only traces of anions could be detected in the wash solution. The pastes obtained were dried at 60 ° C, finely ground and stored in glass containers with screw caps.

Example 2 - Alternative Preparation Method

Montmorillonite (20 g) was weighed into polythene pots containing 200 ml of Na ⁺ and K ⁺ (NH? Or ¹⁾ chloride solution (1.0 mol / 1). The relative ratios of Na and K varied and the total ionic strength was maintained. The vessel was shaken vigorously, and stored for one week with occasional stirring during this time. The mixtures were centrifuged and washed as in Example 1, then dried at about 100 ° C, finely ground, using a mortar and pestle and stored as in Example 1.

Example 3 - Washing experiments

All washing experiments were performed in tergotometers with the conditions given in Table 2:

Table 2

temperature Deň: 32 ° C Washing time 15 min rinse 2x2 min Washing fluid volume 1 liter monitors 50 g Terry textile Liquid: Textile 20: 1 Water (Hardness) 26 “French

All monitors were despatched

Assessment of softening by different clay was made subjectively by pairwise comparison, using a panel of trained assessors.

Montmorillonite clays with exchanged K ^{@ +} and ΝΗ @ ⁺ cations according to Example 1 were added in an amount of 0.5 g / l to phosphate scrubbing powder and tested against a comparative powder not containing clay and a control powder containing Na-montmorillonite material.

The efficacy of all the clays tested is higher than for the comparative trial without the clay, and thus all exhibit a softening effect - see Table 3. However, in the series of clays ΝΗ ^ ^{+ the} material exhibits the same efficacy as the comparative trial. K-exchanged clay exhibits increased softening compared to all mixtures.

Table 3

Hlinka Relative softening no 0 Na-montmorillonite 83 K ⁺ - exchange 100 NH ^ ⁴ ”- replacement 86

Comparison of the softening results for potassium and ammonium exchanged clays shows that the use of ammonium ion, although having an ionic radius similar to potassium ion, does not lead to an increase in clay softening.

Example 4 - Effect of different K / Na ratio with different content ratio 2; again in comparison The results with their use A series of samples with K / Na prepared by the method of Example with zero clay control team in the amount of 0.5 g / l in the phosphate formulation were tested in Table 4. All clays showed improved softening compared to without clay.

Table 4

Hlinka (Na / K) Relative softening (%) no 0 200/0 46 140/60 78 69/140 100

The following phosphate formulation was used in Examples 3 and 4:

parts (weight) Linear alkylsulfonate (Doha 113) 9.0 Non-ionic PAL (Synperonic A7) 1.0 Sodium tripolyphosphate 21.5 Alkaline silicate 5.5 Water 10.3 Sodium carboxymethylcellulose 2.7 50.0 Dose 2,5 g / l

PAL - surfactant

Similar results were obtained with a zeolite base.

Thus, montmorillonite potassium fixation can be used to increase the effectiveness of softening clays during laundering. Without wishing to be bound by theory, this increase is considered to be the result of an effective reduction of the lattice charge of clay. Even though K-exchanged clay may need drying, the overall process is much more convenient than the process involving an expensive calcination step.

Example 5

For this example, ion-exchanged clay was used and the effect of the ion exchange with Na and K electrolytes in the wash was investigated using the conditions of Example 3 except that the experiments were performed using 0.5 g / l of clay in demineralized water to eliminate any effects of detergent ingredients or surfactants. Comparison of clay softening from Na and K solutions of equal ionic strength (10 ^µz mol / l) shows a significantly better potency for the potassium system - Table 5. Sodium and potassium mixtures show similar effects.

Table 5

Relative softening (%) Ash (% by weight) Comparison - without clay 0 0.05 Aluminum + 10 ' ² M NaCl (1) 68 0.17 Aluminum + 10 ' ² mol / 1 KCl (1) 100 0.20 Aluminum + 10 ' ² M NaCl (2) 60 0.18 Clay + 10 ² mol / 1 KC1 (2) 96 0.24

(1) salt solution added at the beginning of the wash cycle (2) salt solution added after 10 minutes to the wash cycle

In all cases, Na-montmorillonite (ex CSM) was added with a content of 0.5 g / L.

Equivalent results to those found in Example 4 were obtained by adding sodium or potassium salt in the middle of the wash cycle, indicating that the effect is valid even after the initial clay-fabric interaction occurred.

Table 5 also shows the results of the washing experiments showing that the increased softening observed in the presence of potassium ions is the result of increased clay deposition.

Example 6

Example 5 was repeated using simulated laundry liquids.

Softening for sodium carbonate solutions containing LAS: nonionic surfactant (NI) (0.83 g / L approximately 9: 1 LAS: NI) was monitored. Experiments using this system were also performed in the presence and absence of zeolite (4A - 1.8 g / L hydrated zeolite).

The results in Table 6 show that potassium increases the potency of clay softening in the presence of both active ingredients and zeolite.

Table 6

agent relative softening Just the foundation 0 Base + clay 66 Base + clay + 10 mol / l KCl 100 Base (clay) (10 ^-2 moles / 1 KCl) zeolite 98

The basic composition is : 0,75 g / l LAS 0.08 g / l NI 1.20 g / l Na2C0 ^

Example 7

This example shows the effect of added potassium on clay softening efficiency in a detergent system comprising a linear alkylsulfonate as an anionic surfactant and a nonionic surfactant in various ratios. Table 7 shows that the efficacy increase due to the use of potassium-treated clay is greater in the 100% anionic formulation. The effect was demonstrated by measuring clay deposition levels (ash). Mixtures of soap and nonionic surfactants showed analogous behavior.

Table 7

% non-ionic PAL % ash (clay deposition) NaCl KC1 0 0.8 1.3 25 0.85 1.05 50 0.8 0.95 75 0.6 0.9

Example 8

The detergency of zeolite systems in the presence and absence of both added potassium and clay was studied using a fabric sensitive to detergent ingredients. The change in reflectance at 460 nm for two different textile samples (Δ R460) was used as a measure of detergency. Reflectance measurements were made on textile before and after washing using an Ultrascan spectrophotometer.

A comparison of the results of equivalent preparations based on either sodium chloride or potassium chloride shows that there is no difference in detergency - see Table 8:

Table 8

Salt (*) £ R460 textile 1 textile 2 NaCl 19.7 10.2 KC1 20.9 11.2

Composition of washing liquid

0.75 g / 1 LA S 0.08 g / 1 Nl (4EO) 1.2 g / 1 Na ₂ CO 4 1.8 g / 1 zeolite 4A 10 ' ² M / 1 salt (*)

Example 9

In Examples 5-8 above, the potassium salt was added in the form of chloride. Potassium can be added in the form of carbonate, replacing sodium carbonate as a source of alkalinity ·

The experiments were performed by examining the clay softening efficiency in the presence of sodium and potassium carbonate. The results (see Table 9) clearly show an increase in potassium carbonate softening, both in the presence and absence of zeolite. Increasing clay softening is thus possible by replacing sodium carbonate with potassium carbonate.

Table 9

Product (*) relatively softening (%) 1.1 x ^10-2 triol / 1 Na2C0q 0 1.1 x ^10-2 mol / 1 Na ^ CO ^ + 0.5 g / 1 of clay 56 1.1 x ^10-2 mol / 1 Ki Con + 0.5 g / 1 of clay 100 1.1 x 10 -2 mol / l K 2 CO 3 + 0.5 g / l clay + 1.8 g / l zeolite 97

(*) All still contain 0.75 g / L LAS and 0.08 g / L Synperonic

A7 ex ICI.

The use of either potassium exchanged clays or, in particular, the addition of potassium salts to clay containing wash liquids to obtain high clay softening efficiency is the simplest and most cost effective method of improving clay efficiency.

Claims (9)

PATENT CLAIMS A detergent composition for laundering and softening fabrics, comprising at least one detergent active, a clay softening fabric, which is bentonite clay, and at least 1% by weight of the total soluble potassium salt formulation, expressed as 00. 2. A detergent composition according to claim 1 wherein the potassium salt is potassium carbonate. 3. A detergent composition according to claim 1, wherein the potassium salt is potassium citrate. Detergent composition according to any one of the preceding claims, characterized in that the bentonite is selected from montmorillonites and hectorites. 5. A detergent composition according to claim 4 wherein the clay is montmorillonite. 6. Use of potassium-modified bentonite clay as fabric softener. 7. A detergent composition for washing and softening fabrics, comprising at least one detergent active, a potassium-modified bentonite clay, such that the level of potassium in the clay is more than 1.5% by weight, expressed as ^0.0. 8. A method for washing and softening fabrics, characterized by. comprising the steps of: (a) adding a detergent powder comprising a mixture of bentonite clay, a detergent active and at least 1% by weight of the total water-soluble potassium salt formulation to form a wash liquid; b) washing the fabric in a liquid; and c) rinsing the wash liquid from the fabric using additional water. 9. A method for washing and softening fabrics comprising the steps of: (a) adding a detergent powder comprising at least one detergent active to a potassium-modified bentonite clay such that the level of potassium in the clay is more than 1.5% by weight, expressed as K-, 0, to form a wash liquid; b) washing the fabric in a liquid; and c) rinsing the wash liquid from the fabric using additional water.