WO1998005752A1

WO1998005752A1 - Laundry bar compositions

Info

Publication number: WO1998005752A1
Application number: PCT/US1996/012886
Authority: WO
Inventors: Johannson Jimmy Tee; Maria Freyja Lajara De Los Reyes
Original assignee: The Procter & Gamble Company
Priority date: 1996-08-07
Filing date: 1996-08-07
Publication date: 1998-02-12
Also published as: AU7006996A

Abstract

Pyrophosphate-built laundry detergent bars with a surfactant system comprising anionic surfactant and certain nonionic polyhydroxy fatty acid amide surfactants. The bars are high sudsing, and have excellent cleaning performance and mildness to skin.

Description

LAUNDRY BAR COMPOSITIONS

FIELD OF THE INVENTION The present invention relates to laundry bar compositions with excellent cleaning, sudsing and skin mildness properties. BACKGROUND OF THE INVENTION

Synthetic laundry bars typically comprise an anionic surfactant such as the alkali metal salt of an alkylbenzene sulfonic acid or alkali metal salt of an alkyl sulfate and one or more alkaline builders such as alkali metal polyphosphates, carbonates or silicates. Because these products are used in intimate contact with skin there is a continuing need to improve their mildness properties. At the same time it is necessary to maintain good cleaning performance, good bar physical characteristics (i.e. good bar feel and resistance to wearing away fast in use). Also, because the consumer of this type of product usually associates good cleaning performance with high sudsing, in most instances it is desirable to maintain high sudsing characteristics when formulating laundry bars.

BACKGROUND ART EP Patent Application 81958. published March 16, 1995, discloses the use of polyhydroxy fatty acid amide surfactants in synthetic laundry bar products. The laundry bars disclosed in that application additionally contain anionic surfactants and polyphosphate and carbonate builders.

SUMMARY OF THE INVENTION The present invention is directed to polyphosphate-built laundry bar compositions with a mulϋ- component surfactant system comprising synthetic anionic surfactants, fatty acid soaps and certain polyhydroxy fatty acid amide surfactants.

DETAILED DESCRIPTION OF THE INVENTION In accordance with the present invention it has been found that polyphosphate-built laundry bars with excellent mildness to skin, cleaning performance, sudsing and physical characteristics can be achieved by using a surfactant system comprising synthetic anionic surfactant, fatty acid soap and certain polyhydroxy fatty acid amide surfactants. Anionic Surfactants

Anionic surfactants which are suitable for use herein include the water-soluble salts, preferably the alkali metal, ammonium and alkyloiammonium salts of organic sulfuric reaction products having in their molecular structure an alkyl group containing from about 10 to about 20 carbon atoms and a sulfonic acid or sulfuric acid ester group. (Included in the term "alkyl" is the alkyl portion of acyl groups.) Examples of this group of synthetic surfactants are the sodium and potassium alkyl sulfates, especially those obtained by sulfating the higher alcohols (Cg.i carbon atoms) such as those produced by reducing the glycerides of tallow or coconut oil; and the sodium and potassium alkylbenzene sulfonates in which the alkyl group contains from about 9 to about 15 carbon atoms, in straight chain or branched chain configuration, e.g., those of the type described in U.S. Patents 2,220,099 and 2,477,383. Especially valuable are linear straight chain alkylbenzene sulfonates in which the average number of carbon atoms in the alkyl group is from about 11 to 13, abbreviated as C_j I .J LAS. The alkali metal salts, particularly the sodium salts of these surfactants are preferred. Other anionic surfactants suitable for use herein are the sodium alkyl glyceryl ether sulfonates, especially those ethers of higher alcohols derived from tallow and coconut oil; sodium coconut oil fatty acid monoglyceride sulfonates and sulfates; and sodium or potassium salts of alkyl ehylene oxide ether sulfates containing about 1 to about 10 units of ethylene oxide per molecule and wherein the alkyl group contains from about 10 to about 20 carbon atoms. In addition, suitable anionic surfactants include the water-soluble salts of esters of alpha- sulfonated fatty acids containing from about 6 to 20 carbon atoms in the fatty acid group and from about 1 to 10 carbon atoms in the ester group; water-soluble salts of 2-acyioxyalkane-l -sulfonic acids containing from about 2 to 9 carbon atoms in the acyl group and from about 9 to about 23 carbon atoms in the alkane moiety; water-soluble salts of olefin and paraffin sulfonates containing from about 12 to 20 carbon atoms; and beta-alkyloxy alkane sulfonates containing from about 1 to 3 carbon atoms in the alkyl group and from about 8 to 20 carbon atoms in the alkane moiety.

Preferred anionic surfactants are Cjo.jg linear alkylbenzene sulfonates and Cιø-i alkyl sulfates, and mixtures thereof.

The amount of anionic surfactant in the compositions herein is from about 4% to about 30%, preferably from about 6% to about 20%. All percentages and ratios set forth in this document are "by weight" unless specified otherwise. Fattv Acid Soap

The fatty acid soaps useful herein are the water soluble salts of fatty acids having from about 8 to about 22 carbon atoms in their alkyl chains, these include the alkali metal soaps such as sodium and potassium as well as the ammonium and alkylolammonium salts of the fatty acids. Preferred soaps are the alkali metal (especially sodium) salts of fatty acids having from about 12 to about 18 carbon atoms in their alkyl chains. These are typically the soaps derived from coconut and tallow fatty acids. Soaps are present in the compositions herein at levels of from about 10% to about 70%, preferably from about 20% to about 50%. Polvhvdroxy Fattv Acid Amide Surfactant The polyhydroxy fatty acid amide surfactants herein have the formula:

0 R.

I I I

R₂ - C - N - Z

wherein: R_j is H, C C hydrocarbyl, 2-hydroxyethyl, 2-hydroxypropyl, or a mixture thereof, preferably C1-C4 alkyl, more preferably C\ or C₂ alkyl, most preferably C_j alkyl (i.e., methyl); and R² is a C5-C32 hydrocarbyl moiety, preferably straight chain C7-C19 alkyl or alkenyl, more preferably straight chain C9- C_]7 alkyl or alkenyl, most preferably straight chain C_j 1-C19 alkyl or alkenyl, or mixture thereof; and Z is a polyhydroxyhydrocarfoyl moiety having a linear hydrocarbyl chain with at least 2 (in the case of gryceraldehyde) or at least 3 hydroxyls (in the case of other reducing sugars) directly connected to the chain, or an alkoxylated derivative (preferably ethoxylated or propoxylated) thereof. Z preferably will be derived from a reducing sugar in a reductive amination reaction; more preferably Z is a glycityl moiety. Suitable reducing sugars include glucose, fructose, maltose, lactose, galactose, mannose, and xylose, as well as glyceraldehyde. As raw materials, high dextrose corn syrup, high fructose corn synip, and high maltose corn syrup can be utilized as well as the individual sugars listed above. These corn syrups may yield a mix of sugar components for Z. It should be understood that it is by no means intended to exclude other suitable raw materials. Z preferably will be selected from the group consisting of -CI_2-(CHOH)_n- CH2-OH, -CH(-CH₂-OH)-(CHOH)_n.ι-CH2-OH, -CH₂-(CHOH)₂(CHOR (CΗOH)-CH₂-OH, where n is an integer from 1 to 5, inclusive, and R' is H or a cyclic mono- or poly- saccharide, and alkoxylated derivatives thereof. Most preferred are glycityls wherein n is 4, particularly -CH2-(CHOH)_ι-CH2-OH.

In the above formulas, R_j can be, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, 2- hydroxy ethyl, or 2-hydroxy propyl. For highest sudsing, R 1 is preferably methyl or hydroxyalkyl. If low sudsing is desired, R_j is preferably C2*Cg alkyl, especially n-propyl, iso-propyl, n-butyl, iso-butyl, pentyl, hexyl and 2-ethyl hexyl.

While polyhydroxy fatty acid amides can be made by the process of Schwartz, U.S. 2,703,798, contamination with cyciized by-products and other colored materials can be problematic. As an overall proposition, the preparative methods described in WO-9,206,154 will afford high quality polyhydroxy fatty acid amides. The methods comprise reacting N-alkylamino polyols with, preferably, fatty acid methyl esters in a solvent using an alkoxide catalyst at temperatures of about 85°C to provide high yields (90-98%) of polyhydroxy fatty acid amides having desirable low levels (typically, less than about 1.0%) of sub-optimally degradable cyciized by-products and also with improved color and improved color stability, e.g., Gardner Colors below about 4, preferably between 0 and 2. (With compounds such as butyl, iso-butyl and n-hexyl, the methanol introduced via the catalyst or generated during the reaction provides sufficient fluidization that the use of additional reaction solvent may be optional.) If desired, any unreacted N- alkylamino polyol remaining in the product can be acylated with an acid anhydride, e.g., acetic anhydride, maleic anhydride, or the like, to minimize the overall level of such residual amines in the product. Residual sources of classical fatty acids, which can suppress suds, can be depleted by reaction with, for example, triethanolamine. By "cyciized by-products" herein is meant the undesirable reaction by-products of the primary reaction wherein it appears that the multiple hydroxyl groups in the polyhydroxy fatty acid amides can form ring structures which are, in the main, not readily biodegradable. It will be appreciated by those skilled in the chemical arts that the preparation of the polyhydroxy fatty acid amides herein using the di- and higher saccharides such as maltose will result in the formation of polyhydroxy fatty acid amides wherein linear substituent Z (which contains multiple hydroxy substituents) is naturally "capped" by a polyhydroxy ring structure. Such materials are not cyciized by-products, as defined herein.

The amount of polyhydroxy fatty acid amide surfactants can range from about 1% to about 20%, typically from about 1% to about 10%, preferably about 3% to 6% by weight of the total compositions herein. Polvphosphate Builder

The laundry bars of the invention contain from about 5% to about 60%, preferably from about 5% to about 25% polyphosphate builder. These builders include alkali metal pyrophosphates, tripolyphosphates and the higher polyphosphates such as trimetaphosphates and phosphate glasses. Preferred builders are the alkali metal pyrophosphates and tripolyphosphates, particularly the sodium salts.

Auxiliary Surfactants and Other Materials

The detergent bars of the present invention can contain optional ingredients commonly used in detergent products. A typical listing of the classes and species optional surfactants, (e.g. nonionic, zwitterionic and amphoteric surfactants) optional alkaline builders such as sodium carbonate trisodium phosphate sodium silicate, etc. and other ingredients useful herein appears in U.S. Pat. No. 3,664,961, issued to Norris on May 23, 1972, and EP 550,652, published on April 16, 1992, incorporated herein by reference.

A particularly preferred optional builder is sodium carbonate. When present, it is used at levels of from about 3% to about 30%. In addition to these auxiliary materials, a hydrσtrope, or mixture of hydrotropes, can be present in the laundry detergent bar. Preferred hydrotropes include the alkali metal, preferably sodium, salts of tolune sulfonate, xylene sulfonate, cumene sulfonate, sulfosuccinate, and mixtures thereof. Preferably, the hydrotrope is added to the linear alkyl benzene sulfonic acid prior to its neutralization. The hydrotrope will preferably be present at from about 0.5% to about 5% of the laundry detergent bar. Other optional materials are set forth as follows. Fabric Softening Clay

The fabric softening clay is preferably a smectite-type clay. The smectite-type clays can be described as expandable, three-layer clays; i.e., alumino-silicates and magnesium silicates, having an ion exchange capacity of at least about 50 meq/100 g. of clay. Preferably the clay particles are of a size that they can not be perceived tactilely, so as not to have a gritty feel on the treated fabric of the clothes. The fabric softening clay can be added to the bar to provide about 1% to about 30% by weight of the bar, more preferably from about 5% to about 20%, and most preferably about 8% to 14%.

While any of the smectite-type clays described herein are useful in the present invention, certain clays are preferred. For example, Gelwhite GP is an extremely white form of smectite-type clay and is therefore preferred when formulating white granular detergent compositions. Volclay BC, which is a smectite-type clay mineral containing at least 3% iron (expressed as Fe2θ3) in the crystal lattice, and which has a very high ion exchange capacity, is one of the most efficient and effective clays for use in the instant compositions from the standpoint of product performance. On the other hand, certain smectite- type clays are sufficiently contaminated by other silicate minerals that their ion exchange capacities fall below the requisite range; such clays are of no use in the instant compositions. Clay Flocculating Agent

It has been found that the use of a clay flocculating agent in a laundry bar containing softening clay provides surprisingly improved softening clay deposition onto the clothes and clothes softening performance, compared to that of laundry bars comprising softening clay alone. The polymeric clay flocculating agent is selected to provide improved deposition of the fabric softening clay. Typically such materials have a high molecular weight, greater than about 100,000. Examples of such materials can include long chain polymers and copolymers derived from monomers such as ethylene oxide, acrylamide, acrylic acid, dimethylamino ethyl methacrylate, vinyl alcohol, vinyl pyrrolidone, and ethylene imine. Gums, like guar gums, are suitable as well. The preferred clay flocculating agent is a poly(ethylene oxide) polymer.

Other Optional Ingredients

A particularly preferred optional component of the present invention is a detergent chelant. Such chelants are able to sequester and cheiate alkali cations (such as sodium, lithium and potassium), alkali metal earth cations (such as magnesium and calcium), and most importantly, heavy metal cations such as iron, manganese, zinc and aluminum. Preferred cations include sodium, magnesium, zinc, and mixtures thereof. The detergent chelant is particularly beneficial for maintaining good cleaning performance and improved surfactant mileage, despite the presence of the softening clay and the clay flocculating agent.

The detergent chelant is preferably a phosphonate chelant, particularly one selected from the group consisting of diethylenetriamine penta(methylene phosphonic acid), ethylene diamine tetra(methylene phosphonic acid), and mixtures and salts and complexes thereof, and an acetate chelant. particularly one selected from the group consisting of diethylenetriamine penta(acetic acid), ethylene diamine tetra(acetic acid), and mixtures and salts and complexes thereof. Particularly preferred are sodium, zinc, magnesium, and aluminum salts and complexes of diethylenetriamine penta(methylene phosphonate) diethylenetriamine penta (acetate), and mixtures thereof. Preferably such salts or complexes have a molar ratio of metal ion to chelant molecule of at least

1:1, preferably at least 2:1.

The detergent chelant can be included in the laundry bar at a level 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 about 1.0%. Such detergent chelant component can be used beneficially to improve the surfactant mileage of the present laundry bar, meaning that for a given level of anionic surfactant and level of detergent chelant, equivalent sudsing and cleaning performance can be achieved compared to a similar bar containing a higher level of the anionic surfactant but without the detergent chelant.

Another preferred additional component of the laundry bar is fatty alcohol having an alkyl chain of 8 to 22 carbon atoms, more preferably from 12 to 18 carbon atoms. Fatty alcohol is effective at reducing the bar wear rate and smear (mushiness) of laundry bars. A preferred fatty alcohol has an alkyl chain predominantly containing from 16 to 18 carbon atoms, so-called "high-cut fatty alcohol," which can exhibit less base odor of fatty alcohol relative to broad cut fatty alcohols. Typically fatty alcohol is contained in the laundry bar at up to a level of 10%, more preferably from about 0.75% to about 6%, most preferably from about 2% to about 5%. The fatty alcohol is generally added to a laundry bar as free fatty alcohol. However, low levels of fatty alcohol can be introduced into the bars as impurities or as unreacted starting material. For example, laundry bars based on coconut fatty alkyl sulfate can contain, as unreacted starting material, from 0.1% to 3.5%, more typically from 2% to 3%, by weight of free coconut fatty alcohol on a coconut fatty alkyl sulfate basis.

Another preferred optional component in the laundry bar is a dye transfer inhibiting (DΗ) ingredient to prevent diminishing of color fidelity and intensity in fabrics. A preferred DΗ ingredient can include polymeric DΗ materials capable of binding fugitive dyes to prevent them from depositing on the fabrics, and decolorization DΗ materials capable of decolorizing the fugitives dye by oxidation. An example of a decolorization DΗ is hydrogen peroxide or a source of hydrogen peroxide, such as percarbonate or perborate. Non-limiting examples of polymeric DTI materials include polyvinylpyrridine N-oxide, polyvinylpyπolidone (PVP), PVP-polyvinylimidazole copolymer, and mixtures thereof. Copolymers of N-vinylpyrrolidone and N-vinylimidazole polymers (referred to as "PVPI") are also preferred for use herein.

Another preferred optional component in the laundry bar is a secondary fabric softener component in addition to the softening clay. Such materials can be used at levels of about 0.1% to 5%, more preferably from 0.3% to 3%, and can include: amines of the formula R4R5R6N, wherein R4 is C5 to C22 hydrocarbyl, R5 and R6 are independently C_ to Cio hydrocarbyl. One preferred amine is ditallowmethyl amine; complexes of such amines with fatty acid of the formula R7COOH, wherein R7 is C9 to C22 hydrocarbyl, as disclosed in EP No. 0,133,804; complexes of such amines with phosphate esters of the formula RsO-P(0)(OH)-OR9 and HO-P(0)(OH)-OR9, wherein Rg and R9 are independently Ci to C20 alkyl of alkyl ethoxylate of the formula -alkyl-(OCH2CH2); cyclic amines such as imidazolines of the general formula l-(higher alkyl) amido (lower alkyl)-2-(higher alkyl)imidazoline, where higher alkyl is from 12 to 22 carbons and lower alkyl is from 1 to 4 carbons, such as described in UK Patent Application GB 2,173,827; and quaternary ammonium compounds of the formula RioRl

wherein Rio is alkyl having 8 to 20 carbons, Rπ is alkyl having 1 to 10 carbons, R_2 and R13 are alkyl having 1 to 4 carbons, preferably methyl, and X is an anion, preferably Cl" or Br", such as C.2-13 alkyl trimethyl ammonium chloride.

Yet another optional component in the laundry bar is a bleach component. The bleaching component can be a source of "OOH group, such as sodium perborate monohydrate, sodium perborate tetrahydrate and sodium percarbonate. Sodium percarbonate (2Na2Cθ3*3H2θ2) is preferred since it has a dual function of both a source of HOOH and a source of sodium carbonate. Another optional bleaching component is a peracid p__r se, such as a formula:

CH3(CH2)w-NH-C(0)-(CH2)_zCθ3H wherein z is from 2 to 4 and w is from 4 to 10. The bleaching component can contain, as a bleaching component stabilizer, a chelating agent of polyaminocarboxylic acids, polyaminocarboxylates such as ethylenediaminotetraacetic acid, diethylenetriaminopentaacetic acid, and ethylenediaminodisuccinic acid, and their salts with water-soluble alkali metals. The bleach components can be added to the bar at a level 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 this invention. It can be a by-product of the surfactant sulfation and sulfonation processes, or it can be added separately. Other filler materials include bentonite and talc.

Calcium carbonate (also known as Calcarb) is also a well known and often used component of laundry bars. Such materials are typically used at levels up to 40%, preferably from about 5% to about 25%.

Binding agents for holding the bar together in a cohesive, soluble form can also be used, and include natural and synthetic starches, gums, thickeners, and mixtures thereof.

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

Optical brighteners are also preferred optional ingredients in laundry bars of the present invention. Preferred optical brighteners are dia ino stilbene, distyrilbiphenyl-type optical brighteners. Preferred as examples of such brighteners are 4,4'-bis{[4-anilino-6-bis(2-hydoxyethyl) amino-l,3,5-trizin- 2-yl]amino}stilbene-2,2'-disulfonic acid disodium salt, 4-4'-bis(2-sulfostyryl) biphenyl and 4,4'-bis[(4- anilino-6-morpholino-l,3,5-triazin-2-yl) amino]stilbene-2,2'-disulfonic acid disodium salt. Such optical brighteners, or mixtures thereof, can be used at levels in the bar of from about 0.05% - 1.0%.

Dyes, pigments, germicides, and perfumes can also be added to the bar composition Processing

The detergent laundry bars of the present invention can be processed in conventional soap or detergent bar making equipment with some or all of the following key equipment: blender/mixer, mill or refining plodder, two- stage vacuum plodder, logo printer/cutter, cooling tunnel and wrapper.

In a typical process the raw materials are mixed in the blender. Alkylbenzene sulfonic acid (when used) is reacted with an alkaline inorganic salt (preferably sodium carbonate) and the resulting partly neutralized mixture is mechanically worked to effect homogeniety and to complete the neutralization of the mixture. Once the neutralization reaction is completed, the soap, polyhydroxy fatty acid amide and any optional surfactants are added, followed by the polyphosphate builder and any additional optional components. If desired, polyphosphate can be used as an alkaline salt in the neutralization. The mixing can take from one minute to one hour, with the usual mixing time being from about two to twenty minutes. The blender mix is charged to a surge tank. The product is conveyed from the surge tank to the mill or refining plodder via a multi-worm conveyer.

After milling or preliminary plodding, the product is then conveyed to a double vacuum plodder, operating at high vacuum, e.g. 600 to 740 mm of mercury vacuum, so that entrapped air is removed. The product is extruded and cut to the desired bar length, and printed with the product brand name. The printed bar can be cooled, for example in a cooling tunnel, before it is wrapped, cased, and sent to storage.

Examples of the invention are set forth hereinafter by way of illustration and are not intended to be in any way limiting of the invention.

EXAMPLE I

An N-alkyl polyhydroxy fatty acid amide (coconut N-Methyl glucamide) useful in compositions of the present invention is prepared as follows:

A reaction mixture consisting of 84.87 g. coconut fatty acid methyl ester, 75 g. N-methyl-D- glucamine, 1.04 g. sodium methoxide and a total of 39.96 g. methyl alcohol (ca. 20% of the reaction mix) is used. The reaction vessel comprises a standard reflux set-up fitted with a drying tube, condenser and - 9 -

mechanical stirring blade. The N-methyl glucamine/methanol mixture is heated with stirring under argon (reflux). After the solution has reached the desired temperature, the ester and sodium methoxide catalyst are added. The reaction mixture is maintained at reflux for 6 hours. The reaction is essentially complete in 1.5 hours. After removal of the methanol, the recovered product weighs 105.57 grams. Chromotography indicates the presence of only traces of undesired ester-amide by-products, and no detectable cyciized by-product.

EXAMPLE II A soap/synthetic laundry bar of the present invention, having the following composition is prepared by conventional blending, milling and plodding procedures.

Component % Weieht

Tallow Soap (Na) 16.00

Coconut Soap (Na) 16.00

Coconut alkyl sulfate (Na) 12.00

Ci2-C_j4 alkyl N-methyl glucamide 4.00

Na tripolyphosphate 5.00

Bentonite 6.00

Talc 17.00

Sodium Carbonate 4.00

Water 15.00

Ti02 1.00

Optical brightener 0.03

NaCl (Salt) 2.00

Miscellaneous 1.97

TOTAL 100.00

The bar is milder than a comparable bar that does not contain N-methyl glucamide surfactant. Moreover, this bar has superior sudsing characteristics and wears away more slowly in use than a comparable bar which does not contain the N-methyl glucamide surfactant.

Claims

WHAT IS CLAIMED IS: 1. A laundry detergent bar comprising:

A. From about 4% to 30% of an anionic surfactant;

B. From about 10% to about 70% of the alkali metal soap of a fatty acid containing from about 8 to about 22 carbon atoms; C. From about 1% to about 20% of a polyhydroxy fatty acid amide of the formula:

O Ri

II I

R₂ - C - N - Z wherein Rj is H, Ci -Cg hydrocarbyl, 2 hydroxyethyl, 2-hydroxypropyl, or a mixture thereof, R2 is a C5-C32 hydrocarbyl moiety, and Z is a polyhydroxyhydrocarbyl moiety having a linear hydrocarbyl chain with at least 2 hydroxyls directly connected to the chain moiety or an alkoxylated deravitive; D. From about 5% to about 60% of an alkali metal polyphosphate.

2. The composition of Claim 1 wherein the level of Component A. is from about 6% to about 20% and the amount of Component B. is from about 20% to about 50%.

3. The Composition of Claim 3 wherein the level of Component D. is from about 5% to about 25%.

4. The Composition of Claim 3 which additionally contains from about 3% to about 30% sodium carbonate.

5. The Composition of any of Claims 1 through 4 wherein the level of Component C. is from about 1% to about 10%

6. The Composition of Claim 5 wherein the level of Component C. is from about 3% to about 6%.

7. A laundry detergent bar comprising:

A. from about 6% to about 20% of an anionic surfactant selected from the group consiting of alkali metal alkyl benzene sulfonates and alkyl sulfates;

B. from about 20% to abouit 50% Cg to C22 alkali metal fatty acid soap; C. from about 1% to about 10% Cj j to C_j9 alkyl or alkenyl N-methyl glucamide;

D. from about 5% to about 25% of an alkali metal polyphosphate selected from the group consisting of tripolyphosphate and pyrophosphate; and

E. from about 3% to about 30% sodium carbonate.

8. The composition of Claim 7 wherein the level of component C. is from about 3% to about 6%.