CN1145095A - Laundry Detergent Bar Containing Fabric Softening Clay - Google Patents

Abstract

A softening clay comprising about 10% to about 60% by weight of anionic surfactant, about 5% to about 60% by weight of detergent builder, about 1% to about 30% smectite type, and A detergent bar comprising from about 0.001% to about 30% by weight of fabric softening clay of a polymeric clay flocculant. A preferred clay flocculant is poly(ethylene oxide) having an average molecular weight of from 100,000 to about 10,000,000. Preferred optional detergent chelating agents are diethylenetriaminepenta(methylene phosphonic acid), diethylenetriaminepenta(acetic acid), 1,2-ethylenediaminetetrakis(methylene Phosphonic acid) Alkali metal, alkaline earth metal and heavy metal salts of 1,2-ethylenediaminetetra(acetic acid), and mixtures thereof.

Description

Laundry Detergent Bar Containing Fabric Softening Clay

Background of the invention

The present invention relates to improved laundry detergent bars. More specifically, it relates to a laundry detergent bar comprising a detergent anionic surfactant, a detergent builder, and a fabric softening clay.

Many communities, especially those where mechanical washing machines are common, wash their clothes with granular and liquid synthetic detergents, while some communities, mostly those where mechanical washing machines are not common, wash their clothes with synthetic organic surfactants and detergents. Laundry bar detergent with built-in detergent.

Technical developments in the field of laundry detergent bars have involved formulating laundry detergent bars. The bar has acceptable lather in warm, cold, and hard and soft water; acceptable in-use wear, hardness, durability, and hand; low staining; and pleasing odor and appearance . Examples of detergent bars include articles described in the following patents and publications: U.S. Patent 3,178,370 (issued to Okenfuss on April 13, 1965, incorporated herein by reference) describes Sodium phosphate, sodium bicarbonate, trisodium orthophosphate, and water laundry detergent bars, and methods of making them; Philippine Patent 13,778 (Anderson, issued October 23, 1980) describes the Laundry bar synthetic detergent of alkali metal salt, about 18% to about 60% alkaline earth metal carbonate, and about 1% to about 20% water; U.S. Patent 4,543,204 (Gervasio, issued October 24, 1985) discloses A laundry bar detergent containing 10-35% higher aliphatic alkyl sulfate, 1-10% higher fatty acid, the fatty acid makes the bar detergent more resistant to damage during handling and storage; U.S. Patent 5,089,174 (1992 February Granted to Kaw on January 18) discloses an improved bar detergent containing an anionic surfactant mixture containing alkyl sulfates and alkylbenzene sulfonates to which a fatty alcohol has been added to effectively reduce the Attrition rate and improved solubility. The disclosed alkyl sulfate/alkylbenzenesulfonate surfactant weight ratio is 90/10-10/90; and Philippine Patent 23,860 (issued to Unilever on November 16, 1982) discloses a surfactant-containing Bar detergent, at least 1/3 of the surfactant is primary alkyl sulfate, 12-60% builder, the builder is selected from orthophosphate, pyrophosphate, and triphosphate at least Composed of two alkali metal phosphates.

Methods of making laundry detergent bars are well known in the art. Examples of methods and processes for making detergent bars are described in the following patents and publications: Philippine Patent 23,689 (issued to Unilever on October 27, 1989) discloses a method for making bars containing 7-45% surfactant A method of forming a detergent comprising the steps of neutralizing an acidic precursor of a detergent surfactant with an alkaline material such as a carbonate, the neutralization being performed on a desiccant/sorbent material such as in the presence of oleum, sulfuric acid, and anhydrous sulfate. Then other components are added before being bar-shaped; A method for a detergent bar comprising the steps of: using an alkaline material (such as a carbonate) in the presence of 0.25-50% by weight of a silica-containing material such as crystalline aluminosilicate, silica gel, and amorphous silica Neutralizes the acidic precursors of detergent surfactants, followed by the addition of other ingredients prior to bar forming.

Improvements to bar detergents have been made using clays to improve their physical properties. Examples of clay-filled detergent bars are described in the following patents and publications: Philippine Patent 17,712 (issued to Unilever on November 9, 1984) discloses a detergent bar containing the following components: Surfactants, builders and 0.5-45% sheet-shaped aluminosilicate fillers such as bentonite and 2.5-57% fine-grained substantially water-insoluble non-sheet-shaped aluminosilicate fillers, the two fillers accounting for 10-60% of the total weight of the bar detergent; Philippine Patent 18,128 (issued to Unilever on March 22, 1985) discloses a bar detergent containing the following components: surfactant for detergent, builder, 0.5-45% flaky aluminosilicate filler, and 10-60% non-builder, mainly water-soluble filler, the above two fillers account for 10.5-60.5% of the bar detergent weight; and Philippine patent 27,321 ( Granted to Colgate Palmolive on June 8, 1993) discloses a bar detergent composition comprising an anionic surfactant at least 15-70% of which is an alkyl sulfate or a 2-sulfoaliphatic alkane 3-10% zeolite as the main builder; up to 60% filler, of which 4-9% is bentonite; the remainder comes from calcium carbonate, sodium carbonate, sulfate, and their mixtures.

Clothes washed with a detergent bar containing softening clay show improved softness. Examples of detergent bars containing softening clay are described in the following patents and publications: Philippine Patent 22,589 (issued to Firmenich & Cie on October 17, 1988) discloses a detergent bar containing the following components: Anionic surfactants, builders, and 5-50% softener which may contain up to 40% montmorillonite such as bentonite with an ion exchange capacity above 50 meq/100 gm.

However, none of the so-called clay-containing detergent bars performed completely satisfactorily. Therefore, there is a need for improved fabric softening performance while maintaining good cleaning and soil removal and other physical performance of bar detergents.

Fine-grained softening clay is often used in operations using granular detergent compositions as part of the granular detergent composition itself, or as a separate detergent additive added to the rinse water of fibrous fabrics, either alone or Use with other softening ingredients. It is well known that clay flocculants can be used with such finely divided softening clays in granular detergent compositions to improve the sedimentation of these clays and thereby improve their clothes softening properties. Examples of granular detergent compositions containing softening clays and clay flocculants are described in the following patents and publications: European Patent EP 0,299,575-Al (published January 18, 1989, The Procter & Gamble Company) discloses Detergent composition of fabric softening montmorillonite clay and macromolecule clay flocculant; and detergent compositions optionally containing a polymeric clay flocculant, the aforementioned montmorillonite clay being treated with an organic wetting agent to enhance its softening properties.

It is an object of the present invention to improve the laundry softening performance of detergent bars containing softening clay while providing good surfactant usage, cleaning action, wear rate, solubility and other detergent bar aesthetics.

Summary of the invention

The laundry detergent bar of the present invention comprises a detergent surfactant, a detergent builder, a fabric softening clay and an effective amount of a clay flocculant to improve the clothes softening properties of the clay. The bar detergent preferably comprises from about 10% to about 60% by weight anionic surfactant, from about 5% to about 60% by weight detergent builder, from about 1% to about 30% smectite-type softening clay, and a polymeric clay flocculant comprising from about 0.001% to about 30% by weight of the softened clay.

The polymeric clay flocculants are preferably selected from poly(ethylene oxide), poly(acrylamide), and poly(acrylate), having a molecular weight of about 100,000-10,000,000.

Detailed description of the invention

The patent specification of this application ends with claims, which clearly point out and specifically propose the patent requirements of the present invention. It is believed that the present invention can be better understood only by carefully reading the following detailed description of the invention. All percentages in this patent specification are calculated by weight, all temperatures are in degrees Celsius, molecular weights are in weight average, and decimals are represented by decimal points (.), unless otherwise specified.

Surfactants for Detergents

The detergent bars of the present invention typically comprise from 10% to about 60% anionic surfactant. Anionic surfactants preferably used are alkyl sulfates (AS) with an alkyl chain of 10-20 carbon atoms; branched alkylbenzene sulfonates (ABS) with an alkyl chain of 10-22 carbon atoms ; Linear alkylbenzene sulfonates (LAS), whose alkyl groups contain 10-22 carbon atoms and mixtures thereof. Preferred detergent bars comprise from about 15% to about 40%, more preferably from about 18% to about 32%, of the above anionic surfactants.

The alkyl portion of the above-mentioned ABS or LAS surfactant preferably contains 10-16 carbon atoms, more preferably 10-14 carbon atoms. The most preferred alkylbenzene sulfonate surfactant is LAS. The alkyl portion of the AS surfactant preferably contains 10-18 carbon atoms, more preferably 12-16 carbon atoms. The AS surfactant may comprise a mixture of a long chain AS, such as 16-18 carbon atoms, and a short chain alkyl group, such as 11-13 carbon atoms. Preferred AS surfactants include coconut alkyl sulfates, tallow alkyl sulfates, and mixtures thereof; most preferred are coconut alkyl sulfates.

The preferred cation for ABS, LAS and AS is sodium, although other useful cations include triethanolamine, potassium, ammonium, magnesium, and calcium, or mixtures thereof.

Preferred anionic surfactants include mixtures of AS and alkylbenzene sulfonates. In the mixture of AS and alkylbenzene sulfonate, the weight ratio of AS surfactant to alkylbenzene sulfonate is usually 10:90-95:5, more preferably 40:60-95:5, most preferably 75: 25 - about 90:10. In a preferred embodiment, the anionic surfactants in the bar detergent comprise AS to LAS in a molar ratio of 80:20 to about 90:10, more preferably about 82:18 to about 88:12, most preferably about 84 :16 to about 87:13 mixtures. The aforementioned detergent bar is disclosed in co-pending Philippine Patent Application 47165-A (filed October 29, 1993, Rodney M. Wise and Belal U. Siddigue), assigned to The Proctor & Gam.ble Co.

detergent builder

The detergent bars of the present invention comprise from about 5% to about 60% by weight of a detergent builder. Preferred detergent bars comprise from about 5% to about 30%, more preferably from about 7% to about 20%, by weight of the detergent bar, of builder. Such detergent builders may be, for example, water-soluble alkali metal salts of phosphoric acid, pyrophosphoric acid, orthophosphoric acid, triphosphoric acid, higher polyphosphoric acid, and mixtures thereof. Preferred builders are the water-soluble alkali metal triphosphates and mixtures of triphosphates and pyrophosphates. Detergent builders can also be non-phosphate builders. Specific examples of non-phosphorus inorganic builders for detergents include water-soluble inorganic carbonates and bicarbonates. Carbonates, bicarbonates and silicates of alkali metals such as sodium and potassium are particularly suitable here.

Sodium carbonate is a particularly preferred ingredient in bar detergents because, in addition to being used as a builder, it also provides alkalinity to the bar detergent for improved cleaning and can also be used for bar processing Neutralizing agent for acidic components added. Sodium carbonate is particularly preferred as a neutralizing inorganic salt for acidic precursors of anionic surfactants such as alkylsulfuric and alkylbenzenesulfonic acids used in detergent bars.

Aluminosilicate ion exchange materials are also suitable. Such aluminosilicates can be crystalline or amorphous in structure and can be either naturally occurring or synthetically produced. Preferred synthetic crystalline aluminosilicate ion exchange materials suitable for use herein are Zeolite A, Zeolite B, and Zeolite X. In a particularly preferred embodiment, the crystalline aluminosilicate ion exchange material is Zeolite A, which has the formula:

Na ₁₂ [(AlO ₂ ) ₁₂ ·(SiO ₂ ) ₁₂ ]·xH ₂ O

In the formula, x is about 20 to about 30, especially about 27.

Water-soluble organic detergent builders such as the alkali metal, ammonium and substituted ammonium salts of polycarboxylic acids are also suitable herein. Specific examples of suitable polycarboxylate builders include the sodium, potassium, ammonium and substituted ammonium salts of the following polycarboxylates or the polycarboxylates themselves: ethylenediaminetetraacetic acid, nitrilotriacetic acid, Succinic acid, mellitic acid, benzene polycarboxylic acid, polyacrylic acid, polymaleic acid, acrylic acid-maleic acid copolymer, polyaspartic acid, and citric acid. The average molecular weight of these polymers is generally less than about 100,000, more preferably about 1,000-10,000. Other suitable polycarboxylate detergent builders are the materials listed in US Patent 3,308,067, issued March 7, 1967 to Diehl, incorporated herein by reference. Mixtures of detergent builders are useful herein.

Copolymers of acrylic acid and maleic acid are preferred as co-builders since it has been seen that the copolymers, in combination with fabric softening clays and clay flocculants, further stabilize and improve clay deposition behavior and fabric softening performance.

Specific examples of preferred builders include sodium triphosphate (STPP) and sodium pyrophosphate (TSPP), and mixtures thereof. Examples of other particularly preferred builders include zeolites and polycarboxylates.

Fabric Softening Clay

The fabric softening clay is preferably a smectite-type clay. Smectite clays may also be referred to as expandable three-layer clays; ie, aluminosilicates and magnesium silicates, having an ion exchange capacity of at least about 30 meq/100 g of clay. The preferred clay particle size is not tactilely perceivable so as not to have a gritty hand on the treated laundry fabric.

There are two types of smectite-type clays with different properties: the first type is alumina present in the silicate lattice; the second type is magnesium oxide present in the silicate lattice. The general formulas of these montmorillonites are Al ₂ (Si ₂ O ₅ ) ₂ (OH) ₂ and Mg ₃ (Si ₂ O ₅ ) ₂ (OH) ₂ for alumina and magnesia, respectively. It should be taken into account that the amount of bound water in the above formula may vary due to the different processes provided to the clay. In addition, atomic substitution of iron and magnesium can occur in the montmorillonite lattice, while metal cations such as Na ⁺ , Ga ⁺⁺ and H ⁺ can co-exist in the bound water to achieve electrical neutralization. Except as described below, cationic substitution of the above formula is immaterial to the use of the clays herein since the useful physical properties of the clays are not substantially altered thereby.

The trilayer aluminosilicates used here are also characterized by their dioctahedral lattice, whereas the trilayer magnesium silicate has a trioctahedral lattice.

As noted above, the clays useful in the compositions of the present invention contain cationic counterions, such as protons, sodium ions, potassium ions, calcium ions, magnesium ions, and the like. The usual approach is to differentiate clays on the basis of one predominantly or totally absorbed cation. Sodium clay, for example, is a clay in which the absorbed cation is predominantly sodium. The above-mentioned absorbed cations can participate in an exchange reaction with cations present in the aqueous solution. A typical exchange reaction involving smectite-type clays can be represented by the following formula:

Since one equivalent of ammonium ion replaces one equivalent of sodium in the above equilibrium reaction, milliequivalents/100g clay (meq/100g) is usually used to measure cation exchange capacity (sometimes called "base exchange capacity").

The cation exchange capacity of a clay is a well known parameter in determining its effectiveness as a fabric softener. The cation exchange capacity can be determined by recognized analytical methods. See, eg, H. van Olphen, "Clay Colloid Chemistry" Interscience Publishers, 1963, and related references cited therein. Preferred clay particles for use in the present invention have a cation exchange capacity of at least about 50 meq/100 g.

The smectite-type clays useful in the compositions herein are well known and many are commercially available. Such clays include, for example, montmorillonite, Volchouskoite, nontronite, bentonite, hectorite, talc, sauconite, and vermiculite. Clays that can be used here are available under various trade names such as Thixogel No. 1 (and "Thixo-Jell") and Gelwhite GP from Georgia Kaolin Co., Elizabeth, New Jersey; Volclay BC from American Colloid Co., Skokie, Illinois and Volclay No.325; Black Hills Bentonite BH 450 from International Minerals and Chemicals; and Veegum Pro and Veegum F from R.T. Vanderbilt. It should be considered that the above-mentioned smectite-type minerals belong to the mixture of various individual metal products. Mixtures of such smectite-type minerals are suitable here.

Any of the smectite-type clays described herein are suitable for use in the present invention, although certain clays are preferred. For example, Gelwhite GP is a very white form of smectite-type clay and is therefore preferred when formulating white granular detergent compositions. Volclay BC is a smectite-type clay mineral containing at least 3% iron (expressed as Fe ₂ O ₃ ) in its crystal lattice and its ion exchange capacity is very high, and it is suitable for this composition from the viewpoint of product performance. One of the most cost effective clays available. On the other hand, certain smectite-type clays are sufficiently mixed with other silicate minerals to reduce their ion exchange capacity to less than necessary and such clays are not useful in the present compositions.

Clay minerals suitable for use herein can be selected based on the fact that they exhibit a true 14A X-ray diffraction pattern. This characteristic pattern, together with the determination of exchange capacity performed in the manner described above, provides the basis for selecting a particular smectite-type mineral for use in the compositions disclosed herein.

Acid-treated bentonite or other softening clays such as those disclosed in Philippine Patent 18,297 (issued May 20, 1985, assigned to Unilever) may also be used as fabric softening clays.

The fabric softening clay can be incorporated into the detergent bar at a level of from about 1% to about 30%, more preferably from about 5% to about 20%, most preferably from about 8% to about 14%, by weight of the detergent bar.

Clay flocculant

High molecular weight clay flocculants are selected to facilitate the improvement of fabric softening clay deposition. Such materials typically have a high molecular weight, greater than about 100,000. Examples of such materials include long chain polymers and copolymers derived from the following monomers: ethylene oxide, acrylamide, acrylic acid, dimethylaminoethyl methacrylate, vinyl alcohol, vinyl pyrrolidone, and aziridine. Gums, such as guar gum, are also suitable.

Preferred clay flocculants are selected from high molecular weight polyethylene oxides, polyacrylamides, and polyacrylates having a molecular weight of from about 100,000 to about 10,000,000. It has been found that the use of clay flocculants in bar detergents containing softening clay unexpectedly promotes improved deposition of softening clay on clothes and improved clothes softening performance by comparison to bars containing softening clay alone. The amount of clay flocculant used in the detergent bar is preferably a practical amount which results in a substantial improvement in fabric softening performance. The amount of clay flocculant used can vary with the type of clay flocculant used, the type of fabric softening clay, and the type and level of other wash adjuncts in the detergent bar. The level of clay flocculant is conveniently expressed as a weight percent of the amount of fabric softening clay in the detergent bar. Clay flocculants are typically present in detergent bars at levels of from about 0.001% to about 30%, more preferably from about 0.01% to about 15%, most preferably from about 0.5% to about 5%, by weight of the fabric softening clay.

The effectiveness of clay flocculants generally increases as the molecular weight of the flocculant increases. The average molecular weight of the polymer is generally from about 100,000 to about 10,000,000, more preferably from about 150,000 to about 5,000,000. As with the level of clay flocculant, the choice of suitable polymer molecular weight will depend on the type of clay and the type of flocculant and other components of the composition.

A preferred clay flocculant is poly(ethylene oxide).

optional components

The detergent bars of the present invention may contain up to about 70% by weight of optional ingredients commonly used in detergent products. Typical listings of optional surfactants, optional builders, and other ingredient classes and forms suitable herein are found in U.S. Patent 3,664,961 (Norris issued May 23, 1972) and European Patent 550,652 (April 1992 16), incorporated herein by reference. The following are representative of such materials and are not intended to be limiting.

Optional Detergent Surfactants: Optional detersive surfactants may comprise up to about 10% by weight of the composition, more preferably from about 0.1% to about 5%. Classes of detersive surfactants which may be used as optional surfactants include anionic, cationic, nonionic, amphoteric and zwitterionic surfactants and mixtures thereof.

Optional anionic surfactants suitable for use as cosurfactants herein include:

Sodium alkyl glyceryl ether sulfates, especially ethers of higher alcohols derived from tallow and coconut oil;

Coconut fatty acid monoglyceride sulfonic acid and sodium sulfate;

Sodium or potassium salt of alkylphenol oxirane ether sulfate, and sodium or potassium salt of methyl ester R-CH(SO ₃ M)-COOR' (in the formula, R is C ₈ -C ₂₂ alkyl or alkenyl , R' is C ₁ -C ₄ alkyl, M is a counter ion, preferably Na or K), such as disclosed in WO-93-05013 (published on March 18, 1992); sulfonate;

Secondary alkyl sulfates, the alkyl chains of which contain 10-20 carbon atoms;

Salts of higher fatty acids (ie "soaps") such as sodium, potassium, ammonium and alkanolammonium salts of higher fatty acids. Soap is made by direct saponification of fats and oils or neutralization of free fatty acids. Particularly suitable are the sodium and potassium salts of mixtures of fatty acids from coconut oil and tallow, i.e. tallow and coconut oil sodium or potassium soaps;

Including alkyl moieties containing 6 to 18 carbon atoms and alkoxy moieties having an average of about 0.5 to about 20 moles of alkoxy, preferably ethoxy units, more preferably about 0.5 to about 5 moles of ethoxy units; base alkoxysulfate, and

Alkyl ethoxy carboxylate RO(CH ₂ CH ₂ O) _x CH ₂ COO ^- M ⁺ , where R is C ₆ -C ₁₈ alkyl; x=0-10, the weight of ethoxylate is distributed like this , so that the amount of material where x is 0 is less than 20%, and the amount of material where x is greater than 7 is less than 25%, where the average value of x is 2-4 when R is C ₁₃ or slightly lower, and when R is higher than C ₁₃ When the average value of x is 3-6; M is alkali metal, alkaline earth metal, ammonium, single, dione and triethanolammonium.

Other optional surfactants may be nonionic and include: alkyl polysaccharides, alkyl polyglucosides, such as those described in US Patent 4,565,647 (Llenado);

Polyhydroxy fatty acid amides RC(O)-N(R')-Z, where R is C ₅ -C ₃₁ hydrocarbon group, preferably C ₁₁ -C ₁₇ alkyl or alkenyl, R' is H, C ₁ - C ₄ hydrocarbyl, 2-hydroxyethyl, 2-hydroxypropyl, or mixtures thereof, preferably methyl, Z is a polyhydroxyl (straight chain) hydrocarbyl chain, at least 3 hydroxyl groups are directly attached to the chain, preferably _-CH2 (CHOH) _{4 -CH2OH} , such as described in European Patent 550,652;

Semi-polar nonionic surfactants, such as water-soluble amine oxides, water-soluble phosphine oxide surfactants, and water-soluble sulfoxide surfactants; and

Water-soluble nonionic synthetic surfactants; broadly defined as compounds formed by the condensation of oxyethylene groups (hydrophilic in nature) with organic hydrophobic compounds (aliphatic or alkylaromatic in nature). The length of the polyoxyethylene group condensed with a particular hydrophobic group can be adjusted without difficulty so that the resulting water-soluble compound has the desired balance between its hydrophilic and hydrophobic moieties.

Cationic surfactants are also useful in the detergent compositions herein. Suitable quaternary ammonium surfactants are selected from mono C ₆ -C ₁₆ , preferably C ₆ -C ₁₀ N-alkyl or alkenyl ammonium salts. The active agent wherein the remaining N-position is substituted by methyl, hydroxyethyl or hydroxypropyl.

Optional surfactants also include amphoteric surfactants containing aliphatic derivatives of heterocyclic secondary and tertiary amines; zwitterionic surfactants containing derivatives of aliphatic quaternary ammonium, phosphonium and sulfonium compounds; 2-sulfonated fatty acids Water-soluble salts of esters; Alkyl ether sulfates ^; Water-soluble salts ^of olefin sulfonates; _β -Alkoxyalkanesulfonates; ^- , where R is C ₆ -C ₁₈ hydrocarbon group, preferably C ₁₀ -C ₁₆ alkyl or C ₁₀ -C ₁₆ amidoalkyl, R' is usually C ₁ -C ₃ alkyl, preferably methyl and R ² is a C ₁ -C ₅ hydrocarbon group, preferably a C ₁ -C ₃ alkenyl group, more preferably a C ₁ -C ₂ alkenyl group. Examples of suitable trialkylammonium carboxylic acid inner salts include cocamidopropyldimethylammonium carboxylic acid inner salt; cetyldimethylammonium carboxylic acid inner salt; _C12-14 amidopropylammonium carboxylic acid inner salt; Inner salt; C _8-14 amidohexyl diethylammonium carboxylic acid inner salt; 4-[C _14-16 amidodiethylammonium]-1-carboxybutane; C _16-18 amidodimethyl Ammonium carboxylic acid inner salt; C _12-16 amidopentane diethylammonium carboxylic acid inner salt; and C _12-16 amidodimethylammonium carboxylic acid inner salt. Preferred trihydrocarbyl ammonium carboxylic acid internal salt is C _12-18 dimethylaminocaproic acid internal salt and C _10-18 amido propane (or ethane) dimethyl (or diethyl) ammonium carboxylic acid internal salt; Ethylsulfotrialkylammonium carboxylic acid inner salt R(R′) ₂ N ⁺ R ² SO ^- ₃ , where R is C ₆ -C ₁₈ hydrocarbon group, preferably C ₁₀ -C ₁₆ alkyl group, more preferably C ₁₂ -C ₁₃ alkyl, R' is usually C ₁ -C ₃ alkyl, preferably methyl, R ² is C ₁ -C ₆ hydrocarbon, preferably C ₁ -C ₃ alkenyl or preferably hydroxyalkylene. Examples of suitable inner salts of sulfotrialkylammonium carboxylic acids include C ₁₂ -C ₁₄ dimethylammonium-2-hydroxypropyl sulfonate, C ₁₂ -C ₁₄ amidopropylamino-2-hydroxypropyl sulfonate Ammonium carboxylic acid inner salt, C ₁₂ -C ₁₄ dihydroxyethyl aminopropane sulfonate, and C ₁₆ -C ₁₈ dimethyl amino hexane sulfonate, while C _12-14 amidopropyl amino-2- Hydroxypropylsulfonium carboxylic acid inner salt is preferred.

In addition to the aforementioned cosurfactants, one or more hydrotropes may also be present in the laundry detergent bar. Preferred hydrotropes include the alkali metal salts of toluenesulfonic acid, xylenesulfonic acid, cumenesulfonic acid, sulfosuccinic acid, and mixtures thereof, preferably the sodium salt. Preferably, the hydrotrope in acid or salt form and substantially anhydrous is added to the linear alkylbenzene sulfonic acid prior to the neutralization operation. The preferred level of hydrotrope is from about 0.5% to about 5% of the laundry detergent bar.

Detergent chelating agents: A particularly preferred optional ingredient of the present invention is a detergent chelating agent. Such chelating agents are capable of sequestering and sequestering alkali metal cations such as sodium, lithium and potassium, alkaline earth metal cations such as magnesium and calcium, and most preferably heavy metal cations such as iron, manganese, zinc and aluminum. Preferred cations include sodium, magnesium, zinc and mixtures thereof. Detergent chelating agents are particularly beneficial for maintaining good wash performance and improved surfactant usage despite the presence of clay softening and clay flocculants. Without being bound by any theory, it is believed that the softened clay structure contains iron (Fe) and other transition metal ions. During the washing operation, calcium and magnesium in the washing water and dirt will replace iron or other transition metal ions, and drive the transition metal ions into the washing solution. These metal ions are known to cause yellowing and graying of fabrics. Chelating agents for detergents can significantly reduce this phenomenon.

A preferred detergent chelating agent is a phosphonic acid chelating agent, especially selected from the group consisting of diethylenetriaminepenta(methylenephosphonic acid), ethylenediaminetetra(methylenephosphonic acid) and mixtures thereof, Salts and complexes, and an acetic acid chelating agent, especially selected from diethylenetriaminepenta(acetic acid), ethylenediaminetetra(acetic acid) and mixtures, salts and complexes thereof. Particularly preferred are the sodium, zinc, magnesium and aluminum salts and complexes of diethylenetriaminepenta(methylenephosphonic acid), diethylenetriaminepenta(acetic acid) and mixtures thereof.

Such salts or complexes have a molar ratio of metal ions to chelating agent molecules of at least 1:1, preferably at least 2:1.

Detergent chelating agents can be present in the bar detergent at up to about 5%, preferably from about 0.1% to about 3%, more preferably from about 0.2% to about 2%, most preferably from about 0.5% to 1.0%. This detergent chelating agent component can advantageously be used to improve the surfactant usage of the present detergent bar, that is, compared to a similar bar detergent having a higher level of anionic surfactant but no chelating agent , a given amount of anionic surfactant and detergent chelating agent, can get the same foaming and cleaning performance.

The chelating agent for detergents can be used in the form of fine particles or granules, or in the form of an aqueous solution or a solvent solution. Methods for the preparation of such salts and complexes are well known, as described in US Patent 4,259,200, issued March 31, 1981, the disclosure of which is incorporated herein by reference. The preferred form is particulate or granular. The particles or granules of the detergent chelating agent can be formed by organic or inorganic binding materials. Suitable organic binding materials are, for example, nonionic surfactants. Suitable inorganic binder materials include sodium triphosphate, sodium carbonate, magnesium sulfate, and the like. Any granulation method known in the art can be used, such as spraying molten nonionic surfactant onto a moving bed of dry metal complex, fluid bed drying, and the like.

Enzymes Another particularly preferred component is detergent enzymes. Non-limiting examples of enzymes include cellulases, lipases, amylases, lipases, maltases, proteases, catalases, and phosphatases. Cellulases, lipases, proteases, amylases, and mixtures thereof are particularly preferred. The useful amount of enzyme is up to 5%. Cellulase enzymes apparently provide fabric maintenance and softening properties due to the in situ enzymatic hydrolysis of amorphous non-crystalline cellulose deposited on damaged cellulose fibers. A particularly preferred cellulase is ^Carezyme® cellulase from Novo Nordisk.

Another useful optional ingredient in the laundry detergent bars of the present invention is a silicate, especially sodium or magnesium silicate. Sodium silicate having a _SiO2 : _Na2O weight ratio between about 1.0:1 and about 3.4:1 can be used in amounts up to about 15%.

Another preferred additional component is a layered crystalline alkali silicate. A preferred, commercially available layered silicate, "SKS-6" (Na ₂ Si ₂ O ₅ ) from HÖchst, is disclosed in US Patent 4,664,839 (issued May 12, 1987). Another layered silicate is disclosed in European Patent 550,048 (July 7, 1993, Kao), which discloses a synthetic chain structure crystalline material whose composition can be represented by the following anhydrous formula:

xM ₂ O·ySiO ₂ ·zM′O

In the formula, M represents Na and/or K; M' represents Ca and/or Mg; y/x is 0.5-2.0; z/x is 0.005-1.0, and the chain structure is within the range of 900-1200cm ^-1 of Raman spectrum Scattering peaks appearing at least 970 ± 20 cm ^-1 within. Such layered silicate materials are particularly preferred because they provide both alkalinity and calcium sequestering or builder functionality.

Another preferred additional component for detergent bars is a fatty alcohol having an alkyl chain of 8-22 carbon atoms, more preferably 12-18 carbon atoms. Fatty alcohols are effective in reducing the wear rate and staining (pasteiness) of the present bar detergents. Preferred are fatty alcohols whose alkyl chains mainly contain 16-18 carbon atoms, so-called "high cut fatty alcohols", which have less impure fatty alcohol odor than broad cut fatty alcohols. The level of fatty alcohol in the detergent bar is usually up to 10%, more preferably from about 0.75% to about 7%, most preferably from about 2% to about 5%. Fatty alcohols are usually added to the formulations of the present invention in the form of free fatty alcohols. However, low levels of fatty alcohols can be added to bar detergents as impurities or unreacted raw materials. For example, the content of free coconut fatty alcohol as unreacted raw material in the bar detergent based on coconut fatty alkyl sulfate is 0.1%-3.5%, more typically 2%-3% by weight of coconut fatty alkyl sulfate. %.

Free fatty alcohols can also be used as foam boosters to enhance and prolong the development and persistence of foam. To promote sudsing, it is preferred that the fatty alcohol has an alkyl chain primarily of 12-14 carbon atoms and is present in the composition at a level of from about 0.5% to about 3%. The amount of narrow-cut _C12 alkyl alcohol is preferably 0.5%-2%.

Another preferred component of the detergent bar comprises a soil release polymer. Such soil release polymers can be used at levels up to 5%, preferably from about 0.05% to about 3%, more preferably from about 0.2% to about 1.0%. Soil release polymers enable improved multi-cycle washing of bar detergent laundry. Preferred soil release polymeric materials include those disclosed in US Patent 4,877,896 (issued October 31, 1989) and US Patent 5,182,043 (issued January 26, 1993), which are incorporated herein by reference.

A preferred soil release polymer is a substantially linear sulfoaroyl terminated ester having a molecular weight of from about 500 to about 20,000 wherein the ester includes, on a molar basis:

(1) about 1-about 2 moles of sulfobenzoyl-terminated units, (MO ₃ S)(C ₆ H ₄ )-C(O)-, where M is a salt-forming cation;

(II) From about 2 to about 50 moles of oxy-1,2-propyleneoxy units or mixtures thereof with oxyethyleneoxy units, so long as the molar ratio of oxy-1,2-propyleneoxy:oxyethyleneoxy is about 1:10 and about 1:1; and

(III) about 1 to about 40 moles of terephthaloyl units, as long as the molar ratio of said (II) and (III) units is between about 2:1 and about 1:24; Options include:

(IV) 0 to about 30 moles of 5-sulfoisophthaloyl units, -(O)C(C ₆ H ₃ )(SO ₃ M)C(O)-, where M is a salt-forming cation; or

(V) 0 _to about 25 moles of poly(oxyethylene)oxy units, -( _OCH2CH2 ) _nO- , wherein the average degree of ethoxylation n is between 2 and about 100; or

(VI) 0 to about 30 moles of said mixture of (IV) and (V) two units in a molar ratio of (IV):(V) between about 29:1 and about 1:29.

Preferred abovementioned substantially linear sulfoaroyl-terminated esters include, on a molar basis:

(I) about 2 moles of sulfobenzoyl-terminated units of _the formula ( _MO3S )( _C6H4 )-C(O)- (wherein M is sodium);

(II) about 14 moles of oxygen-1,2-propyleneoxy units, or a mixture thereof with oxyethyleneoxy units in a molar ratio of oxygen-1,2-propyleneoxy:oxyethyleneoxy of about 1:0 to about Between 1:7; and

(III) about 11 moles of terephthaloyl units; and

(IV) About 2 moles of 5-sulfoisophthaloyl units of the formula -(O)C(C ₆ H ₃ )(SO ₃ M)C(O)- (wherein M is sodium), of which at least 20% are esters The molecular weight is about 800-20,000.

Another preferred soil release polymer is a sulfonated polyethoxy/propoxy terminated ester oligomer comprising: (I) from about 1 to about 2 moles of the formula ( _MO3S )(H ₂ ) _m (CH ₂ CH ₂ O)(RO) _n -sulfonated polyethoxy/propoxyl capping unit, where M is a salt-forming cation selected from sodium and tetraalkylammonium, m Is 0 or 1, R is ethylene, propylene or their mixture, n=0-2; (II) about 0.5-about 66 moles are selected from the following units: a) oxyethylene oxygen unit; b) oxyethylene oxygen and oxy-1,2-propyleneoxy units wherein the molar ratio of oxyethyleneoxy to oxy-1,2-propyleneoxy is between 0.5:1 and about 10:1; and c) a) or b) Mixtures with poly(oxyethylene)oxy units wherein the degree of polymerization of the poly(oxyethylene)oxy units is 2-4; as long as the degree of polymerization of the poly(oxyethylene)oxy units is 2, poly(oxyethylene) ) oxygen units to all II) units in a molar ratio between 0:1 and about 0.33:1; ) units in a molar ratio between 0:1 and about 0.22:1; and when the poly(oxyethylene)oxy unit has a degree of polymerization of 4, the molar ratio of poly(oxyethylene)oxy units to all II) units is between Between 0:1 and about 0.14:1; (III) about 1.5 to about 40 moles of terephthaloyl units; and (IV) 0 to about 26 moles of 5-sulfoisophthaloyl units, -(O)C( C ₆ H ₃ )(SO ₃ M)C(O)-, where M is a salt-forming cation. Preferred oligomers of the above esters have a molecular weight of from about 500 to about 20,000, more preferably from about 500 to about 5,000.

A particularly preferred ester oligomer has the structure:

NaO ₃ S(CH ₂ CH ₂ O) ₂ -C(O)-(C ₆ H ₄ )-C(O)O-[-CH ₂ CRH-OC(O)-(C ₆ H ₄ )-C( O)O-] ₄ -

-[-CH ₂ CRH-OC(O)-(C ₆ H ₄ )SO ₃ Na-C(O)O-] ₁ -CH ₂ CH ₂ OCH ₂ CH ₂ SO ₃ Na

where R is H or _CH3 in a ratio of about 1.8:1.

The soil release polymer can be added to the bar composition during the manufacturing process in liquid or pellet form. In a preferred embodiment, the soil release polymer is in the form of low density, porous particles. Such porous soil release polymers are prepared by spray drying a liquid soil release polymer solution, alone or with one or more carrier materials, by self-spray drying methods well known in the art to remove substantially all free moisture or other solvent liquid.

Another preferred optional ingredient in bar detergents is a dye transfer inhibiting (DTI) ingredient to prevent impairing the color fidelity and intensity of fabrics. A preferred DTI patch may include a polymeric DTI material capable of binding fugitive dyes to prevent deposition of the dyes onto the fabric, and a decolorizing DTI material capable of decolorizing the fugitive dyes by oxidation. An example of a decolorizing DTI is hydrogen peroxide or a source of hydrogen peroxide such as percarbonate or perborate. Non-limiting examples of polymeric DTI materials include polyvinylpyridine N-oxide, polyvinylpyrrolidone (PVP), PVP-polyvinylimidazole copolymers, and mixtures thereof.

More precisely, the polyamine N-oxides preferred for use herein comprise units of the formula: R-Ax-P; where P is a polymerizable unit to which an N-O group may be attached, or N-O The group can be attached to two units to become part of a polymerizable unit; A is one of the following structures: -NC(O)-, -C(O)O-, -S-, -O-, -N=; x is 0 or 1; R is aliphatic, ethoxylated aliphatic, aromatic, heterocyclic, or alicyclic, or any combination thereof, to which the nitrogen of the N-O group may be attached, or the N-O group is part of such a group . Preferred polyamine N-oxides are those wherein R is a heterocyclic group such as pyridine, pyrrole, imidazole, pyrrolidine, piperidine and derivatives thereof.

The NO group can be represented by the following general formula: In the formula, R ₁ , R ₂ , R ₃ are aliphatic, aromatic, heterocyclic or alicyclic groups or their combinations; x, y and z are 0 or 1; the nitrogen of the NO group can be connected to any of the above groups or Become part of the above-mentioned base. The pKa of the amine oxide units of the polyamine N-oxides is <10, preferably <7, more preferably <6.

Any polymer backbone can be used so long as the amine oxide polymer formed is water soluble and dye transfer inhibiting. Examples of suitable polymeric backbones are polyvinyls, polyalkylenes, polyesters, polyethers, polyamides, polyimides, polyacrylates and mixtures thereof. The polymers may include random or block copolymers where one monomer type is an amine N-oxide and the other monomer type is an N-oxide. The amine N-oxide polymer typically has a ratio of amine to amine N-oxide of 10:1 to 1:1,000,000. The number of amine oxide groups present in the polyamine oxide may vary depending on the copolymerization or degree of N-oxidation employed. Polyamine oxides can be prepared in almost any degree of polymerization. Its average molecular weight is usually in the range of 500-1,000,000, more preferably 1,000-500,000, most preferably 5,000-100,000.

Herein, copolymers of N-vinylpyrrolidone and N-vinylimidazole polymers (referred to as "PVPI") are also preferred. The average molecular weight of PVPI is preferably 5,000-1,000,000, more preferably 5,000-200,000, most preferably 10,000-20,000. (The average molecular weight range is determined by light scattering as described in Barth et al., Chemical Analysis. Vol. 113, "Modern Methods of Polymer Characterization", the disclosure of which is incorporated herein by reference). The molar ratio of N-vinylimidazole to N-vinylpyrrolidone in the PVPI copolymer is usually 1:1-0.2:1, more preferably 0.8:1-0.3:1, most preferably 0.6:1-0.4:1. These copolymers can be either linear or branched.

The compositions of the present invention may also contain polyvinylpyrrolidone ("PVP") having an average molecular weight of from about 5,000 to about 400,000, preferably from about 5,000 to about 200,000, more preferably from about 5,000 to about 50,000. Examples of PVP are disclosed, for example, in European Patent-A-262,897 and European Patent-A-256,696, incorporated herein by reference. Compositions containing PVP may also contain polyethylene glycol ("PEG") having an average molecular weight of from about 500 to about 100,000, preferably from about 1,000 to about 10,000. The weight ratio of PEG to PVP is from about 2:1 to about 50:1, more preferably from about 3:1 to about 10:1.

One or more polymeric DTI materials may also be used in combination with one or more decolorizing DTI materials. DTI materials are usefully utilized in detergent bars at levels up to about 10%, preferably from about 0.05% to 5%, more preferably from about 0.2% to about 2%.

Another preferred optional ingredient in detergent bars, in addition to the softening clay, is an auxiliary fabric softening ingredient. Such materials are used in amounts of about 0.1% to 5%, more preferably 0.3% to 3%, and may include amines of the formula R ₄ R ₅ R ₆ N, where R ₄ is C ₅ -C ₂₂ hydrocarbyl, R ₅ and R ₆ is independently C ₁ -C ₁₀ hydrocarbyl. Preferred amines are ditallow methylamine; complexes of the above-mentioned amines with fatty acid R ₇ COOH, wherein R ₇ is a C ₉ -C ₂₂ hydrocarbon group, described in European Patent _0,133,804 ; )(OH)-OR ₉ and HO-P(O)(OH)-OR ₉ complexes, where R ₈ and R ₉ are independently an alkyl-(OCH ₂ CH ₂ )alkyl ethoxylate C ₁ -C ₂₀ alkyl; cyclic amines such as imidazolines of the general formula 1-(higher alkyl)amido(lower alkyl)-2-(higher alkyl)imidazoline, wherein the higher alkyl contains 12- 22 carbons, _lower ^alkyl _containing 1-4 ^carbons , such as _described in British Patent _{Application 2,173,827} ; An alkyl group of 20 carbon atoms, R ₁₁ is an alkyl group containing 1-10 carbon atoms, R ₁₂ and R ₁₃ are alkyl groups containing 1-4 carbon atoms, preferably methyl, X is an anion, preferably ^Cl- or Br ^- , such as C _12-13 alkyltrimethylammonium chloride.

Yet another optional ingredient in the detergent bar is a bleach ingredient. The bleaching component may be a source of -OOH groups such as sodium perborate monohydrate, sodium perborate tetrahydrate and sodium percarbonate. Sodium percarbonate (2Na ₂ CO ₃ ·3H ₂ O ₂ ) is preferred because it has the dual function of HOOH source and sodium carbonate source.

Another optional bleach component is a peracid itself, such as:

CH ₃ (CH ₂ ) _w -NH-C(O)-(CH ₂ ) _z CO ₃ H

In the formula z=2-4, w=4-10. (When the compound of the above formula is z=4 and w=8, it is called NAPAA hereinafter). The bleaching component may contain the following polyaminocarboxylate chelating agents as bleach component stabilizers; polyaminocarboxylates such as ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, and ethylenediaminediaminodibutylene Acids, and their salts with water-soluble alkali metals. The bleach component can be added to the bar detergent at levels up to 20%, preferably from about 1% to about 10%, more preferably from about 2% to about 6%.

Sodium sulfate is a well-known filler that is compatible with the compositions of the present invention. It can be a by-product of the surfactant sulfation and sulfonation process, or it can be added separately.

Calcium carbonate (also known as Calcarb) is also a well known and commonly used bar detergent ingredient. Such materials are typically used in amounts up to 40%, preferably from about 5% to about 25%.

Binders can also be used to hold the detergent bars together in a viscous soluble state and include natural and synthetic starches, gums, thickeners, and mixtures thereof.

A soil suspending agent may be used. In the present invention it is used in combination with a fabric softening clay/clay flocculant balanced to provide optimum wash and fabric softening performance. Soil suspending agents may also include the water-soluble salts of carboxymethylcellulose and carboxyhydroxymethylcellulose. A preferred soil suspending agent is commercially available from BASF Corp. as Sokolan ^® , an acrylic/maleic acid copolymer. Other soil suspending agents include polyethylene glycols having a molecular weight of about 400-10,000; ethoxylated mono- and polyamines and their quaternary salts.

Optical brighteners are also a preferred optional ingredient in the detergent bars of the present invention. Preferred optical brighteners are diaminostilbene, distyryldiphenyl type optical brighteners. A preferred exemplified brightener of this type is 4,4'-bis{[4-anilino-6-bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino} Stilbene-2,2'-disulfonic acid disodium salt, 4,4'-bis(2-sulfostyryl)biphenyl and 4,4'-bis[(4-anilino-6-morpholinyl -1,3,5-Triazin-2-yl)amino]stilbene-2,2'-disulfonic acid disodium salt. Such optical brighteners, or mixtures thereof, can be used in the bar detergent at levels from about 0.05% to about 1.0%.

Dyes, pigments, bactericides, and fragrances can also be added to the detergent bar compositions.

Processing:

Conventional bar soap or detergent manufacturing equipment can be used to manufacture the laundry detergent bar of the present invention, including some or all of the following major equipment: blending/mixing mill, mill or finishing scroll press, two-stage Vacuum scroll presses, markers, printer/cutters, cooling tunnels and wrappers.

In a typical process, the fabric softening clay and clay flocculant are mixed with other raw materials, usually in a blender. Alkylbenzenesulfonic acid (if used) is added to the mixture of basic inorganic salts (preferably including sodium carbonate) and the resulting partially neutralized mixture is treated mechanically to render the mixture homogeneous and completely neutralized. Once the neutralization reaction is complete, the alkyl sulfate surfactant is added, followed by the remaining ingredients. Mixing can be performed for 1 minute to 1 hour, with typical mixing times being 2-20 minutes. The mixed material of the blender is discharged into the buffer tank, and the product is transported from the buffer tank to the roller mill or the refining screw press through the multi-worm conveying device.

Alkylbenzenesulfonic acids (HLAS) can be prepared by well-known methods such as using SO ₃ or oleum. Excess mineral sulfuric acid ( _H2SO4 ) may preferably be included in the HLAS feedstock, which, when neutralized _, helps it raise the temperature of the product due to the heat of neutralization of the mineral sulfuric acid.

Alternatively, the fabric softening clay and clay flocculant can be added independently at other times and places in the above process, depending on the type of equipment and the type of formulation being prepared.

After rolling or pre-molding, the product is transferred to a two-stage vacuum scroll press operating at high vacuum, eg, 600-740 mm Hg, to remove entrapped air. Extrude and cut the product into a predetermined strip length, and print the product logo. The printed detergent bars can be cooled, for example in cooling tunnels, before being wrapped, boxed and sent to the warehouse.

Examples of detergent bars of the present invention are listed in the following table by way of illustration and not limitation.

Various bar detergent compositions of each embodiment can be manufactured by the above-mentioned method

1 2 3 4 5 6 7 8 9 10

(Weight _percentage ) NACFAS 19.13 16.88 25.50 22.50 22.50 13.50 13.50 25.50NA (C _12-18 ) LAS _{3.38 5.63} 4.50 20.00 2.00.00 Na 3.00 3.00 3.00 3.00 3.00 3.00 3.00DTPP ^1.7 0.70 0.70 0.70 0.70 0.70 0.70 0.70 0.70 1.50PEO-300M ² 0.30 0.30 0.30 0.30 0.30 0.15PEO-600M 0.20 0.20 0.20PEO-1.2MM 0.15膨润土粘土 10.0 10.0 10.0 10.0 12.0 12.0 12.0 10.0 12.0 10.0Sokolan CP-5 ³ 0.70 0.70 0.70 0.70 0.70 0.70 1.00 0.70 0.70 0.70TSPP 5.00 5.00STPP 15.00 15.00 5.00 15.00 10.00 10.00 15.00 15.00 5.00沸石1.25 1.25 1.25 1.25 1.25 1.25 25.00 2.50 2.50 2.00月桂酸钠9.00 9.00SRP-A ⁴ 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.15

Protease ⁵ 0.10 0.10 0.10 0.10 0.10

Amylase ⁶ 0.75 0.75 0.75 0.75 Lipase 0.10 0.10 Cellulase ⁷ 0.15 0.15 0.15 0.15

remainder ⁸

1. Diethylene triamine penta(sodium phosphonate)

2. PEO is ethylene oxide, molecular weight as indicated.

3. Sokolan CP-5 is a maleic acid-acrylic acid copolymer.

4. SRP-A is

NaO ₃ S(CH ₂ CH ₂ O) ₂ -C(O)-(C ₆ H ₄ )-C(O)O-[-CH ₂ CRH-OC(O)-(C ₆ H ₄ )-C( O)O-] ₄ -

- _[ - _{CH2CRH - OC (} O)-( _{C6H4 ) SO3Na} -C(O)O-] _{1- CH2CH2OCH2CH2SO3Na} ,

where R is H or _CH3 in a ratio of about 1.8:1.

5. Protease activity 1Au/gm raw material.

6. Amylase activity 100,000 amu/gm raw material.

7. Carezyme ^® cellulase, Novo Nordisk company supplies active 5000Cevu/gm raw material.

8. The remainder includes water (about 2%-8%, including combined water), sodium sulfate, calcium carbonate, and other auxiliary ingredients.

Claims (17)

1. A laundry detergent bar comprising:

(a) a surfactant for a detergent, which is a surfactant for a detergent,

(b) a builder for a detergent which comprises a builder for a detergent,

(c) a fabric softening clay, and

(d) a clay flocculating agent in an amount sufficient to improve the laundry softening performance of the fabric softening clay.

2. A laundry bar according to claim 1, the detergent comprising:

(a) from about 10% to about 60% by weight of an anionic surfactant,

(b) from about 5% to about 60% by weight of a detergency builder,

(c) from about 1% to about 30% of a smectite-type softening clay, and

(d) a polymeric clay flocculating agent present in an amount of from about 0.001% to about 30% by weight of the fabric softening clay.

3. Detergent bar as claimed in claim 2, wherein the anionic surfactant is selected from alkyl sulphates having alkyl chains of 10 to 20 carbon atoms, linear alkyl benzene sulphonates (LAS) having alkyl chains of 10 to 22 carbon atoms, branched Alkyl Benzene Sulphonates (ABS) having alkyl chains of 10 to 22 carbon atoms, and mixtures thereof.

4. A detergent bar AS claimed in claim 3 wherein the surfactant comprises a mixture of Alkyl Sulphate (AS) and linear alkyl benzene sulphonate (LAS) in a molar ratio AS: LAS of from 70: 30 to 100: 0.

5. The detergent bar of claim 2, wherein the detergent builder comprises sodium tripolyphosphate, tetrasodium pyrophosphate, or mixtures thereof.

6. A detergent bar as claimed in claim 5, wherein the builder is 10% to 20% sodium tripolyphosphate.

7. The detergent bar of claim 2 comprising from about 5% to about 20% fabric softening clay.

8. The detergent bar of claim 7 comprising from about 8% to about 14% fabric softening clay.

9. A detergent bar as claimed in claim 8, wherein the fabric softening clay is bentonite.

10. A detergent bar as claimed in claim 2 wherein the clay flocculating agent has a molecular weight of from 100,000 to about 10,000,000.

11. A detergent bar as claimed in claim 10, wherein the clay flocculating agent is poly (ethylene oxide).

12. The detergent bar of claim 11 wherein the poly (ethylene oxide) has a molecular weight of from about 150,000 to about 5,000,000.

13. The detergent bar of claim 12 wherein the poly (ethylene oxide) is present in an amount of about 0.5% to about 5%.

14. The detergent bar of claim 2 further comprising from about 0.1% to about 3% of a detergent sequestrant selected from the group consisting of diethylene triamine penta (methylene phosphonic acid), diethylene triamine penta (acetic acid), alkali metal salts thereof, and mixtures thereof.

15. The detergent bar of claim 14 wherein the detergent sequestrant is present at a level of from 0.2% to about 2%.

16. A laundry bar detergent comprising:

(a) from about 18% to about 32% of an anionic surfactant selected from the group consisting of alkyl sulfates, alkyl benzene sulfonates, and mixtures thereof.

(b) From about 10% to about 20% phosphate builder selected from the group consisting of triphosphates, pyrophosphates, and mixtures thereof,

(c) from about 8% to about 14% of a smectite-type softening clay, and

(d) a polymeric poly (ethylene oxide) having a molecular weight between 150,000 and 3,000,000 and being present in an amount of from about 0.5% to about 5% by weight of the fabric softening clay for use as a clay flocculant.

17. A detergent bar as claimed in claim 16 further comprising from about 0.1% to about 3% of the sodium salt of diethylenetriamine penta (methylene phosphonic acid).