CA2092194C

CA2092194C - Liquid detergent compositions

Info

Publication number: CA2092194C
Application number: CA002092194A
Authority: CA
Inventors: Julie Anne Dyet; Peter Robert Foley
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1990-09-28
Filing date: 1991-09-25
Publication date: 1996-11-19
Anticipated expiration: 2011-09-25
Also published as: AU8735291A; SK25393A3; EG19516A; CZ281716B6; DE69113055T2; AU664023B2; IN185274B; CA2092194A1; EP0550636A1; IE76141B1; EP0550636B1; MA22303A1; HUT64390A; WO1992006171A1; BR9106935A; AR244328A1; GB9021217D0; NZ240022A; PT99087B; TR26013A

Abstract

Aqueous unbuilt liquid or gel-form detergent compositions are provided comprising, from 15 % to 65 % by weight of a core surfactant mixture, comprising from 5 % to 95 % by weight of the mixture of a water soluble anionic sulphate or sulphonate sur-factant salt together and from 5 % to 95 % by weight of the mixture of one or more compounds of formula (I), wherein Z is a poly-hydroxy hydrocarbyl moiety having a linear hydrocarbyl chain with at least three hydroxy groups connected directly to the chain, said moiety being derived from glucose and mixtures thereof with maltose, the maltose comprising not more than 33 % of the mixture, R is a C6-C16 hydrocarbyl radical and R1 is a C1-C4 alkyl or C2-C4 hydroxyalkyl group, a 0.12 % s? tion of the sur-factant mixtures of the compositions having an interfacial tension (IFT) of less than 0.2 Pa.cm at 48 °C and a polypropy-lene cup (PPC) greasy soil removal value of at least 1.4 x that of the anionic surfactant component(s) alone. Preferred op-tional ingredients include amide, betaine and ethoxylated C9-C11 fatty alcohol suds modifiers.

Description

LIQUID DETERGENT COMPOSITIONS

Fiel~ of Invention This invention relates generally to aqueous liquid detergent compositions and more particularly to liquid detergent compositions intended to remove soils of a largely greasy nature from hard surfaces such as dishes and other articles used in food preparation and consumption.

Backaro~n~ of the I~vention Liquid detergent compositions intended for use as dishwashing products conventionally take the form of aqueous solutions containing a misture of one or more sulphate and sulphonate anionic deterqents as 'core' surfactant materials together with a suds promoting or stabilising agent. The suds stabilisation agent can 'ake a number of forms but is normally an amide derivative, an amine oside, an ethosylated aliphatic alcohol, a zwitterionic surfactant such as a betaine, or a misture of several of these. Usage levels of these types of materials are conventionally in the range of 2-8% normally 3-5% by weight of the composition.
*

W O 92/06171 PC~r/US91/06977 2 0 9 ~ 1 9 4 - 2 -One ~roup of amide derivatives that have been suggested for suds promoting and stabilising purposes are the N-alkanoyl N-alkyl glucamines. These materials are derived from glucose and can be prepared by reacting a lower alkylamine with glucose to form a glucamine and then treating this with a methyl ester of a fatty acid of the required chain length to give the N-alkanoyl-N-alkyl glucamine.

Compounds of this type are taught in e.g. US-A-2703798, WO83/04412 and G8-A-809060. The last named patent discloses detergent compositions comprising at least one water soluble salt of an organic sulphuric reaction product having in its molecular structure a sulphuric acid or a sulphonic acid radical and an amide derivative of the above type in an amount of from 5% to 60% by weight of the water soluble organic sulphuric reaction product. The amide derivatives are stated to provide an improvement in the sudsing characteristics of the compositions at temperatures below 100F particularly in Latin American countries where washing is carried out at temperatures as low as 60F.
Whilst the patent envisages that the surfactant combination can be u~ed alone, the preferred and esemplified embodiments are granular products incorporating phosphate builder and sodium sulphate filler.

The Applicants have now discovered that unbuilt liguid or gel-form detergent compositions containing, as core surfactants, combinations of certain N-alkanoyl -N-alkyl glucamines with sulphated or sulphonated surfactants, provide a significant improvement in the removal of greasy soils from hard surfaces together with superior sudsing mileage performance and appreciable skin mildness benefits relative to known products. Although misture~ of anionic sulphate or sulphonate surfactants and N-alkanoyl -N-alkyl glucamines have been proposed as a means of obtaining improvements in the sudsing of built products at low wash temperatures, the performance aspects of greasy soil removal and skin mildness properties that have how been found for the mistures have, hitherto, not been recognised.

~- -3- 2o92l 94 Therefore, according to the present invention, there is provided an unbuilt liquid or gel-form detergent composition in the form of a physically stable aqueous solution comprising from 15~ to 65~ by weight of the composition of a core surfactant mixture, comprising by weight of the mixture, a) from 5~ to 95~ of at least one water-soluble anionic sulphate or sulphonate surfactant salt;
b) from 95~ to 5~ by weight of the mixture of one or more compounds having the general formula R-CON~R1 wherein Z is a polyhydroxy hydrocarboxyl moiety having a linear hydrocarbyl chain with at least three hydroxy groups connected directly to the chain, said moiety being derived from glucose and mixtures thereof with maltose, the maltose comprising not more than 33~ by weight of the mixture, R is a saturated or unsaturated aliphatic group of from 8 to 16 carbon atoms or a mixture of such groups and R1 is a C1-C4 alkyl or C2-C4 hydroxyalkyl group; whereby a 0.12~ by weight aqueous solution of the surfactant mixture of said composition, in water of 2 Clark mineral hardness (Ca:Mg ratio of 3:1) and temperature of 48C, has i) a spinning drop interfacial tension (IFT) of less than 0.2 Pa cm using a triolein soil of 99.7~ purity;

X'' ` _ -4- 20921 94 ii) a greasy soil removal value in the Polypropylene Cup (PPC) Test of at least 1.4 x the value obtained in the same test under the same conditions using a 0.12~ solution of the anionic surfactant component(s) alone.

For the purpose of the present invention `physically stable' is taken to mean the maintenance of a single phase condition, without precipitation, after 3 months storage at a temperature of 21C. Where the product incorporates an opacifier no, or minimal, settlement of the opacifier should have occurred.
Furthermore for the purposes of the IFT & PPC test measurements of the present invention, the cation(s) of the water soluble anionic sulfate or sulfonate surfactant shall be such as to correspond to the cation(s) in the detergent composition, and where a mixture of cations is present, in the weight proportions in which each cation is present in the mixture.

Preferred compositions in accordance with the invention employ component b) compounds in which the polyhydroxyhydrocarbyl moieties are derived from glucose or mixtures thereof with maltose in which maltose comprises <25~ by weight of the mixture. Commercially available technical grade glucose contains maltose as an impurity at a level of up to 5~ by weight. For the purposes of the present invention, references hereinafter to glucamines are to be construed as material ~r including up to 5~ by weight of the corresponding material derived from maltose.

Suitable anionic sulphate or sulphonate surfactants include C10-Cl6 alkyl ethoxy sulphates containing an average of up to 6 moles of ethylene oxide per mole of alkyl ethoxysulphate, C10-Cl8 paraffin sulphonates, and N-Cg-Cl7 acyl-N-C1-C4 alkyl glucamine sulphates.

Useful compositions in accordance with the invention incorporate an anionic surfactant system comprising from 9~ to 18~ by weight of the composition of a primary C12-C14 alkyl ethoxy sulphate stock containing an average of from 0.4 to 4.0 ethylene oxide groups per mole of C12-C14 alkyl ethoxy sulphate, preferably from 0.3 to 3.0, together with from 9~ to 15~ by weight of the composition of N-coconut acyl-N-methyl glucamine.

Preferred compositions employ an anionic surfactant to glucamine weight ratio of between 2:1 and 1:1. Particularly preferred compositions contain from 10~ to 1890 by weight of C12-C14 alkyl ethoxy sulphate and from 7% to 15~ by weight of the glucamine surfactant. The alkyl ethoxy sulphates themselves comprise a mixture of material containing an average of approximately 0.8 moles of ethylene oxide/mole and material containing an average of approximately 3.0 moles of ethylene oxide/mole in a weight ratio of between 2:1 and 5:1 preferably approximately 4:1.

X

_ -5a-Preferably compositions in accordance with the invention also contain 1~-8~, most preferably 2~-7~ by weight of a suds booster selected from C10-Cl6 alkyl mono or di-C2-C3 alkanolamides, C12-C14 alkyl or alkyl amido betaines, C12-C14 alkyl sulphobetaines, C10-Cl6 alkyl di C1-C4 alkyl or di C2-C4 hydroxyalkyl amine oxides, Cg-Cl2 primary alcohol ethoxylates containing an average of from 7 to 12 ethylene oxide groups per mole of alcohol and mixtures thereof.

Preferred suds boosters comprised mixtures of C12-C14 alkyl betaine, in an amount of from 1~ to 5~ preferably from 1.5~ to 3~ by weight of the composition, together with Cg-Cl2 primary alcohol ethoxylate (preferably C10 alkyl EO8) in an amount of from 6~ to 8~ by weight of the composition.

Another preferred component of such compositions is Mg++, at a level of up to 1.5~ more preferably from 0.5~ to 1.0~ by weight of the compositions. Especially preferred compositions also contain calcium in addition to the magnesium ion at a level of from 0.3~ to 0.5~ by weight.

X

WOi2/0617ig ~ ~ PCT/US91/06977 DescriDtion of the Invention Detergent compositions in accordance with the present inventlon comprise a misture of core surfactants in an amount of from 15% to 65% by weight of the composition, preferably from 2q% to 50% and morç preferably from 22~ to 40% by weiqht. The misture comprises from 5% to 95% by weight of the misture of at least one water-soluble anionic sulphate or sulphonate surfactant salt together with from 95~ to 5% by weiqht of the misture of a N-C8-C16 acyl-N-Cl-C4 alkyl glucamine nonionic surfactant.
Preferably the misture comprises from 20% to 80% of the anionic surfactant and from 80~ to 20% of the alkyl glucamine, and most preferably from 40~ to 70% anionic surfactant and from 60% to 30% alkyl glucamine.

The anionic surfactant can essentially be any organic sulphate or sulphonate surfactant ~alt but is usually selected from Cll-C15 alkyl benzene sulphonates, C10-Cl6 alkyl sulphates and their ethosy analogues containing up to sis moles of ethylene oside per mole of alkyl ethosy sulphate, C13-C18 paraffin sulphonates C10-Cl6 olefin sulphonates, C10-C20 alkyl glyceryl ether sulphonates, Cg-Cl7 acyl-N-Cl-C4 alkyl or C2-C4 hydrosyalkyl glucamine sulphates and mistures of any of the foregoing. Preferably the anionic surfactant is selected from alkyl ethosy sulphates, alkyl glyceryl ether sulphonates and paraffin sulphonates.

Alkyl benzene sulphonates useful in compositions of the present invention are those in which the alkyl group, which is substantially linear, contains 10-16 carbon atoms, preferably 11-13 carbon atoms, a material with an average carbon chain length of 11.8 being most preferred. The phenyl isomer distribution, i.e. the point of attachment of the alkyl chain to the benzene nucleus, is not critical, but alkyl benzenes having a high 2-pheny~ isomer content are preferred.

_ -7- 2092 1 94 suitable alkyl sulphates are primary alkyl sulphates in which the alkyl group contains 10-16 carbon atoms, more preferably an average of 12-14 carbon atoms preferably in a linear chain.
C10-Cl6 alcohols, derived from natural fats, or Ziegler olefin build-up, or OXO synthesis, form suitable sources for the alkyl group. Examples of synthetically derived materials include Dobanol 23 (RTM) sold by Shell Chemicals (UK) Ltd., Ethyl 24 sold by the Ethyl Corporation, a blend of C13-C1s alcohols in the ratio 67% C13, 33~ C15 sold under the trade name Lutensol by BASF GmbH and Synperonic (RTM) by ICI Ltd., and Lial 125 sold by Liquichimica Italiana. Examples of naturally occurring materials from which the alcohols can be derived are coconut oil and palm kernel oil and the corresponding fatty acids.

Alkyl ethoxy sulphate surfactants comprise a primary alkyl ethoxy sulphate derived from the condensation product of a C10-Cl6 alcohol with an average of up to 6 ethylene oxide groups. The C10-Cl6 alcohol itself can be obtained from any of the sources previously described for the alkyl sulphate component. C12-C13 alkyl ether sulphates are preferred.

Conventional base-catalysed ethoxylation processes to produce an average degree of ethoxylation of 6 result in a distribution of individual ethoxylates ranging from 1 to 15 ethoxy groups per mole of alcohol, so that the desired average can be obtained in a variety of ways. Blends can be made of material having different degrees of ethoxylation and/or X

different ethoxylate distributions arising from the specific ethoxylation techniques employed and subsequent processing steps such as distillation. For example, it has been found that equivalent sudsing and grease removal performance to that given by a blend of alkyl sulphate and alkyl triethoxy ether sulphate can be obtained by reducing the level of alkyl sulphate and using an alkyl ether sulphate with an average of approximately two ethoxy groups per mole of alcohol. In preferred compositions in accordance with the present invention a mixture of alkyl ethoxy sulphates is used, combining material having an average degree of ethoxylation from 0.4 to 1.0, more preferably approximately 0.8, with material having an average degree of ethoxylation of from 2.0 to 4.0 or preferably approximately 3Ø Secondary alkane sulphonates useful in the present invention have from 13 to 18 carbon atoms per molecule, more desirably 13 to 15 atoms per molecule. These sulphonates are preferably prepared by subjecting a cut of paraffin, corresponding to the chain lengths specified above, to the action of sulphur dioxide and oxygen in accordance with the well-known sulphoxidation process. The product of this reaction is a secondary sulphonic acid which is then neutralized with a suitable base to provide a water-soluble secondary alkyl sulphonate.
Similar secondary alkyl sulphonates may be obtained by other methods, e.g. by the sulphochlorination method in which chlorine and sulphur dioxide are reacted with paraffins in the presence of actinic light, the resulting sulphonyl chlorides being hydrolysed and neutralized to form the secondary alkyl X' 209~ ~4 -8a-sulphonates. Whatever technique is employed, it is normally desirable to produce the sulphonate as the monosulphonate, having no unreacted starting hydrocarbon or having only a limited proportion thereof present and with little or no inorganic salt by-product. Similarly, the proportions of disulphonate or higher sulphonated material will be minimized but some may be present. The monosulphonate may be terminally sulphonated or the sulphonate group may be joined on the 2-carbon or other carbon of the linear chain. Similarly, any accompanying disulphonate, usually produced when an excess of sulphonating agent is present, may have the sulphonate groups distributed over different carbon atoms of the paraffin base, and mixtures of the monosulphonates and disulphonates may be present.

Mixtures of monoalkane sulphonates wherein the alkanes are of 14 and 15 carbon atoms are particularly preferred wherein the sulphonates are present in the weight ratio of C14-C1s paraffins in the range from 1:3 to 3:1.

X

Qlefin sulphonates useful in the present invention are mi~tures of alkene-l-sulphonates, alkene hydrQsysulphonates, alkene disulphonates and hydro~ydisulphonates and are described in the commonly assigne~ US-A-3~32880 issued to P.F. Pflaumer & A. Kessler on July 2~ ~967.

Suitable alk~l glyceryl ether sulphonates are those derived from ethers of coconut oil and tallow.

Other sulphate sur~actants include the N-Cg-C17 acyl-N-Cl-C4 alkyl g~lucamine sulphates, preferably those in which the Cg~Cl7 acyl group is derived from coconut or palm kernel ~il. These materials can be prepared by the method di~closed in US-A-2717894.

The counter ion for the anio~ic surfact~nt component c~n be any one of sodium, potassi~, m~gnesium, ammonium or alk~nol-_mmonium or a mixture t~reof. For liquid compositions of the invention, ~o~ium i~ the preferred counter ion but potassium i~ prefer~d over ~odium where it i9 of importance that the composit~ions of the invention are completely cle~r ~nd h~v~ a high re~istance to precipit~te form~tion.

In gel-form compositions of the invention, s~ium is preferred over potassium or ammonium for the p~rposes of forming a gel. Preferred liquid detergent comp~sitions in accordance with the invention have a chill point ress than 8C preferably less than 5C, and are at least partl~lly neutralised by ammonium ions.

- -lO- 2092 1 94 Where calcium and/or magnesium ions are present they can either be introduced as the oxide or hydroxide to neutralise the surfactant acid or can be added to the composition as a water soluble salt. However the addition of appreciable levels of such salts to dishwashing compositions in accordance with the invention raises the temperature at which inorganic salt crystals form in the compositions on cooling and the amount added in this way should therefore be minimised.

In preferred compositions according to the invention, mixtures of calcium and magnesium ions may be added in order to provide up to 1~ Ca++ by weight of the composition, more preferably from 0.3~ to 0.5~ Ca++ and up to 1.50~ Mg++, more preferable from 0.5~ to 1.0~ by weight. The preferred mixtures are rich in magnesium and more preferably provide a Ca++:Mg++ weight ratio of from 1:1 to 1:4. Compositions incorporating Mg++
and/or Ca++ are especially valuable for conditions of very low water hardness (<2 Clark) and also for product concentrations greater than 0.5~ by weight.

The second core surfactant component of the unbuilt liquid compositions of the invention is a compound of the general formula O Rl Il /
R C - N Z

X' wherein Z is a polyhydroxy hydrocarbyl moiety having a linear hydrocarbyl chain with at least three hydroxy groups connected directly to the chain, said moiety being derived from glucose and mixtures thereof with maltose, the maltose comprising not more than 33~ by weight of the mixture, R is a saturated or unsaturated aliphatic group of from 8 to 16 carbon atoms, or a mixture of such groups, and R1 is a C1-C4 alkyl or C2-C4 hydroxyl alkyl group.

R may be derived from any of the sources of hydrocarbyl groups discussed hereinbefore with reference to the anionic surfactant but is preferably natural in origin.

Preferably R has an average chain length of from 12 to 14 carbon atoms and is derived from coconut oil or palm kernel oil. R1 is preferably a methyl group.

Synthesis of the subject glucamine compounds is known in the art and does not form part of the present invention. As noted hereinbefore, US-A-2703798 discloses a representative process for preparing N-alkanoyl-N-alkyl glucamines which process has two principal steps. The first step involves reacting glucose and a primary alkylamine in the presence of hydrogen and a hydrogenation catalyst under elevated temperature and pressure to form glucamine. This is then reacted with an ester at elevated temperature to form the N-alkanoyl-N-alkyl glucamine.

It has been found advantageous to add a low level of sodium methoxide as a catalyst in this second step.

X

-lla-Preferred levels of the N-alkanoyl-N-alkyl glucamine in liquid and gel-form compositions of the present invention lie between 8~ and 25~ by weight, more preferably between 9~ and 18~ and most preferably between 10~ and 15~ by weight.

Physically stable compositions in accordance with the invention can be formulated with calcium ions in the absence of magnesium ions, but require the use of N-alkanoyl-N-alkyl glucamines of high purity in which the levels of unreacted starting materials, impurities and by-products, particularly fatty acids, are minimised.

In the broadest aspect of the invention the balance of the liquid detergent composition can be made up by water or, in the case of a gel-form composition by a gelling agent and water. However in preferred compositions, other functional components are also included and the combined weights of the anionic surfactant(s) and glucamine components lie in the range from 20~ to 40~, more preferably from 22~ to 30~ by weight.

A highly desirable optional component is one or more suds modifiers or promoters, normally present at an individual level of from 1~ to 8~ by weight of the composition.

X

20~19 - 12 - PCT/US91/06977 Certain of these materials also have additional functional value as e.g. soil suspending agents. One such suds promoting agent is a C10 C16 alkyl mono- or di-C2-C3 alkanolamide, esamples including coconut alkyl monoethanolamide, coconut alkyl d.e.hanolamide and paim kernel and coconut alkyl mono-and di-isopropanol amides.
The palm kernel or coconut alkyl residue may either be ~whole cut', including the C10 and C16~fractions or may be the so-called 'narrow-cut' C12-C14 fraction, Synthetic sources of the C10-C16 alkyl qroup can also be used.

Another useful suds promoting agent is a zwitterionic surfactant of general formula ,R2 Rl - (Y)n ~ Rt _ (R3)mX

wherein Rl is C10-C16 alkyl, R2 is Cl-C3 alkyl, OH
R3 is a -(CH2)3 group or a -(CH2-CH - CH2) group, Y is - C - 41 - (CH2)3 -, n & m are O or 1, and X~ is CH2COO- or SO3;

provided that where X~ is CH2COO-, m is O, and where X~ is SO3, n is O and m is 1.

More preferably Rl has an average carbon chain length of from 12 to 16 carbon atoms and may be derived from synthetic sources, in which case the chain may incorporate some branching, or from natural fats and oils, in which case the chains are linear and may include minor amounts of C8-C10 and C14-C18 moieties. Synthetic sources for the Rl group may be the ~ame as tho~e mentioned previously for the alkyl group in the anionic surfactant component.

2092 ~ 94 A further class of suds promoting agents useful in the invention are the amine oxides of general formula R1R2R3N ~o wherein R1 is an alkyl group containing from 10 to 16 carbon atoms and R2 and R3 are each independently selected from C1-C3 alkyl and C2-C3 hydroxy alkyl groups.
Preferred members of this class include dimethyldodecyl amine oxide, dimethyl tetradecyl amine oxide, bis-(2 hydroxyethyl) dodecylamine oxide and analogues thereof in which the dodecyl or tetradecyl moiety is derived from natural sources such as coconut or palm kernel oil.

A preferred suds modifying agent is an ethoxylated alcohol or a mixture of ethoxylated alcohols of defined constitution.

The ethoxylated alcohol comprises a C6-C13 aliphatic alcohol ethoxylate containing an average of from 1.5 to 25, more preferably from 2 to 15 and most preferably from 6 to 10 moles of ethylene oxide per mole of alcohol. The aliphatic alcohol ethoxylate contains not more than 1~ by weight of unethoxylated alcohol where the ethoxylated alcohol contains an average of less than 8 moles of ethylene oxide and not more than 2~ by weight of unethoxylated alcohol where the ethoxylated alcohol contains an average of from 8 to 25 moles of ethylene oxide per mole of alcohol.

The starting alcohol may be a primary or secondary alcohol but is preferably a primary alcohol which may be derived from natural or synthetic sources. Thus natural fats or oils, or X' _ -14- 20921 94 products of Ziegler olefin build up reactions or OXO synthesis may all be used as the source of the hydrocarbon chain, the structure of which may be linear or branched in type.

The preferred alcohol chain length range is from Cg to Cll as it has been found that the sudsing volume and mileage performance of compositions in accordance with the invention is optimum when incorporating ethoxylates made from such alcohols. It is also desirable for performance reasons that the hydrophilic-lipophilic balance (HLB) of the ethoxylated alcohol is in the range from 8.0 to 17.0, more preferably from 11.0 to 17.0 and most preferably from 11.0 to 15Ø A
preferred alcohol ethoxylate is a primary alcohol ethoxylate containing an average of 10 carbon atoms in the alkyl chain, condensed with an average of 8 ethylene oxide groups per mole of alcohol.

As discussed with respect to alkyl ethoxy sulphate as the anionic surfactant component, the normal (base catalysed) ethoxylation process to produce an average degree of ethoxylation EaV of 6 results in a distribution of ethoxylate species which ranges from 1 to 15 moles of ethylene oxide per mole of alcohol. An increase in EaV causes some change in this distribution, principally a reduction in the level of unethoxylated material, but an increase in EaV from 3 to 5 will still leave approximately 5-1096 of such material in the ethoxylated product.

- -14a- 2092 1 94 In the liquid dishwashing detergent compositions of the invention, this level of unethoxylated material will give rise to phase stability/chill point problems and/or will result in a product having a fatty alcohol odour which is unacceptable to consumers and cannot be masked by conventional detergent perfumes. It has been found that the maximum level of unethoxylated alcohol that can be tolerated in the ethoxylated alcohol component is 1~ by weight. More preferably the unethoxylated alcohol level is not more than 0.7~ and most preferably is less than 0.5~ by weight of the ethoxylated alcohol component.

x-.l WO92/06171 209~19~
.
_ 1~
Distillation under vaeuum is employed to remove the undesired material and this also removes a portion of the monoethosylate fraction, thereby inereasinq the EaV of the remaining material. In preferred embodiments of the invention the level of monoethosylate is not more than 5%
by weight of the ethosylated aleohol.

~n preferred compositionQ in aeeordanee with the invention, eombinations of the ~uds modifiers or promoters are used, eaeh being present ~t a level of from 1% to ~0% more preferably from 2% to 8% by weight. one ~ueh preferred combination is a Cl2-Cl4 alkyl dimethyl betaine and a Cg-Cll aleohol condensed with an average of from 7 to 9 moles of ethylene oxide per mole of aleohol, ~eh material being present in an amount of from 2% to 8% by weight of the eompo~ition.

In preferred eompositions the balanee of the formula eomprises a hydrotrope-water system in which the hydrotrope may be urea, a Cl-C3 aliphatie aleohol, a lower alkyl or dialkyl benzene sulphonate salt sueh as toluene sulphonate, sylene sulphonate, or eumene sulphonate, or mistures of any of these. Normally a single hydrotrope will be adequate to provide the required phase stability, but eompositions in aeeordanee with the present invention preferably employ a misture sueh as urea-aleohol-water, aleohol-lower alkyl benzene sulphonate-water or urea-lower alkyl benzene sulphonate-water in order to aehieve the desired viseosity, and to remain stable and easily pourable. For eompositions having an organie aetive Wo92/o61~1o9~l9 ~ PCT/US9l/06977 _ 16 _ concentration less than about 40% by weight, the preferred alcoholic hydrotrope is ethanol which is employed at from 3% to 10% by weight of the composition, preferably at from 4% to 8%, usually in admi~ture with urea. For compositions having an organic active concentration greater than about 40% by weiqht, mistures of ethanol with urea and/or lower alkyl benzene sulphonates are preferred.
Mistures of hydrotropes can, of course, be employed for cost effectiveness reasons irrespective of any stability/viscosity considerations.

Optional ingredients of the liquid detergent compositions of the invention include opacifiers such as ethylene glycol distearate, thickeners such as guar gum, antibacterial agents such as glutaraldehyde and Bronopol (RTM), antitarnish agents such as benzosytriazole, heavy metal chelating agents such as ETDA or ETDMP, perfumes and dyes. The pH of the compositions may be anywhere within the range 6.0-8.5.but as manufactured the compositions normally have a pH in the range 6.5-7.3 and are subjected to a final pH trimming operation to obtain the desired finished product pH. For coloured products the pH
preferably lies in the range 6.5-7.2 in order to maintain colour stability.

The compositions of the invention can be made in a number of ways but it is preferred that any zwitterionic surfactant included therein is incorporated towards the end of the making process if not actually forming the last ingredient to be added. This minimises the risk of any degradation of the zwitterionic surfactant under the acid conditions existing at the beginning of the making process and also facilitates the control of the viscosity of the finished product. The glucamine surfactant should not be exposed to a pH lower than 4 or higher than 10 to prevent hydrolysis of the surfactant.

Thus, the anionic surfactant(s) can be made as aqueous solutions of alkali metal or ammonium salts with pH adjusted between 4 and 10 which are then mixed together with the N-alkanoyl-N-alkyl glucamine, followed by any ethoxylated nonionic surfactant and other suds booster(s) and the hydrotrope, after which any calcium or magnesium ion can be introduced as a water soluble salt such as the chloride or sulphate. Any zwitterionic surfactant and minor ingredients are then added at the same time as the pH and viscosity are adjusted. This method has the advantage of utilising conventional techniques and equipment but does result in the introduction of additional chloride or sulphate ions which can increase the chill point temperature (the temperature at which inorganic salts precipitate as crystals in the liquid).

In preferred compositions containing an alkyl ethoxy sulphate as the anionic surfactant, the desired alcohol and alcohol 20921 ~4 ethoxylate can be mixed together and a single sulphation and neutralisation can then be carried out on these two materials.
For this, the alcohol and alcohol ethoxylate should be mixed in a weight ratio lying in the range from 4:3 to 1:6. In the most preferred technique however, a single alcohol ethoxylate stock is produced in which the levels of alcohol and ethoxylated alcohol species are controlled to provide the desired ratio of these starting materials.

Sulph(on)ation of the alcohol and alcohol ethoxylate can employ any of the conventional sulph(on)ation agents such as sulphur trioxide or chlorosulphonic acid. Neutralisation of the alkyl ether sulphuric acid and the alkyl sulphuric acid is then carried out with the appropriate alkali or with a magnesium, calcium or magnesium/calcium oxide or hydroxide slurry. If the amount of anionic surfactant is not sufficient to permit all of the desired Ca++ and Mg++ ions to be added in this way, the remainder can then be added in the form of a water soluble salt.

Gel compositions of the present invention can be prepared using the general method described in U.S. Patent No. 4,615,819.

Compositions in accordance with the invention are characterised by a low interfacial tension, (IFT) which is an indication of the ability to emulsify grease and oily soils, a high polypropylene cup (PPC) weight loss, which demonstrates X

the ability to remove greasy soils from surfaces and suspend the soils in solution, together with a superior skin mildness.
This combination is not normally found in liquid detergent composltlons.

Moreover, compositions in accordance with the invention display superior suds mileage performance in both hard and soft water, by comparison with prior art compositions.

The test methods used to measure these parameters are described below.

I) Interfacial Tension (IFT) Measurement of IFT gives an indication of the ability of a surfactant sample to emulsify a soil under a defined set of conditions. IFT was determined by means of a Spinning Drop Tensiometer and a University of Texas Model 500 manufactured by the University of Texas, Austin, Texas, USA. Two instruments were employed, viz. a Model SITE 04, manufactured by Kruss GmbH Wissenscaftliche Laborgerate, Borsteler Chaussee 85-99a, D2000 Hamburg 61 FRG under conditions representative of those encountered in European manual dishwashing practice.
Thus, measurements were made at a sample temperature of 48C +
1C using a product concentration of 0.12~ by weight in water of either 2 Clark or 18 Clark hardness having a Ca:Mg ratio of 3:1 on a molar basis. The soil was Triolein of 99.7~

purity (the remaining 0.3~ comprising mixed free fatty acids) X`~

_ -20-supplied by ALDRICH Chemical Company Ltd. New Road, Gillingham, Dorset, England. Results were quoted in Pa cm (lPa cm = 10 dynes/cm).

2) Polypropylene Cup Weiqht Loss (PPC) The Polypropylene Cup Test method measures the overall grease handling capability of a product under conditions simulating those found in manual dishwashing practice. The test involves the measurement of the amount of solid fat removal from the base of a polypropylene cup at a temperature below that at which the fat melts.

A fat soil is prepared by making a mixture of the following fats:

70~ solid 100~ vegetable oil (Spry CRISP'N'DRY
manufactured by Van den Berghs, Burgess Hill, W.
Sussex, England) 30~ liquid 100~ corn oil (MAZZOLA manufactured by CPC(UK) Ltd., Claygate House, Esher, Surrey, England) The mixture is heated until it becomes miscible, after which it is cooled and stored at a temperature <0C. For use, approximately 150 ml of fat is melted in a glass beaker and held at 70-75C. Fifteen 250 ml clean, dry, polypropylene X

TRIPOUR cups are each weighed and 6.00 + 0.03g fat are weighed into each by pouring directly into the base of the cup without spillage on to the sides. The cups are held level and the fat allowed to solidify for 2-3 hours in a constant temperature room at 21 + 1C.

A 0.12~ solution of the test product is prepared at 50-55C
and 100 + 0.lg added to each of five glass jars which are then sealed with a lid. The sealed jars are placed in a water bath located in the constant temperature room and set at 45-46C
such that the solution in each jar is at a temperature of 43.8 + 0.1C. A similar procedure is followed for each product under test as well as for the standard product against which the test products are being compared.

The contents of a jar are then poured into a cup down the side wall, taking care not to disturb the fat in the bottom and the cup is stood level for 1/2 hour at 21C before being transferred to an ice bath and held for 10 minutes. Upon cooling a fat deposit line develops at the surface of the solution in the cup. This pouring and cooling sequence is carried out for each cup-jar combination. After 10 minutes each cup is emptied swiftly and the cup interior dried to remove all material adhering to the cup walls between the rim and the level of the fat line. The cup is then stood upside down on absorbent kitchen roll to drain for 10-15 minutes before being dried in an oven for two hours at 30C followed by a further hour at 50C. The cups are then reweighed. An X

- -21a- 20921 94 average weight difference between the original weight of fat and that remaining after the test is calculated for the five samples. This difference is divided by the weight difference obtained using the standard product to give a value that expresses the performance ratio between the test and standard products. Products in accordance with the invention display a performace ratio of greater than about 1.3 preferably at least about 1.4.

For the purposes of the test the standard product should have a grease handling performance in the same general area as that of the experimental product at the same concentration. This can be achieved by adjusting the weight ratio of the liquid and solid fat serving as the soil composition so that the standard (reference) product provides 20-35~ fat removal under the conditions of the test while the test product can have a fat removal of from 20 to 80~. The same batch of fat must be used for the test and reference products.

3) Total Suds and Suds Milaqe Total suds is the total volume of suds generated during a standard dishwashing test and is a measure of the perceived foaming ability of the formulation. Suds mileage is a measurement of the soil loading required to reduce the suds of a test solution to a defined minimum under standard conditions of product concentration, temperature and water hardness. It reflects the perceived useful life of a manual dishwashing y. ~, _ -21b- 20921 94 solution. Suds mileage of the compositions under identical test conditions was made using a prepared mixed food soil and a prepared greasy soil in the mechanical sudsing test method described.

Test Conditions Product Concentration 0.12 Water Temperature 48C
Water Hardness 2 Clark and 18 Clark X

W O 92/06171 PC~r/US91/06977 2092~9 4 Mi~ed Food Soil - 22 -Rice/Mince/Egg ~Real Meal~
1 s 392g Tin Tyne Brand Minced Beef & Onion 1 s 439g Tin Ambrosia Creamed Rice Pudding2 1 Egg 25 mls 2~ Mi~ed Free Fatty Acid (MFFA) in Corn Oil~
25 mls Corn Oil Greasy Soil Cake Mis Slurry 30g Sponge Mi~3 60g 2% MFFA in Corn Oil~

1 Marketed by Master Foods, Rings Lynn, Norfolk, England.
2 Marketed by Ambrosia Creamery, Lifton, Devon, England.
3 Marketed by McDougalls Catering Foods Ltd., Imperial Way, Warton Grange, Reading, England.
4g Oleic Acid, 4g Linoleic Acid, 2g Stearic Acid, 5g Palmitic Acid, 735g Pure Corn Oil.

Test Metho~
The method uses 4 cylinders of length 30 cm and diameter 10 cm fised side by side, and rotatable at a speed of 24 rpm about a central asis. Each cylinder is charged with 500 mls of product solution at a concentration of 0.12% and a temperature of 48-C. The outer two cylinders are used for one of the products being compared and the inner two for the other product.

WO92/06171 2 ~ 9 2 1 9 4 PCT/US91/06977 The cylinders are rotated for 2 minutes, stopped, the initial suds are measured and a soil load is then added typically in 2ml aliquots. After l minute the cylinders are restàrted and allowed to rotate for l minute. The suds height is noted and 2 mls of the soil is added to each cylinder. After l minute the cylinders are restarted.
This process continues until the suds height in the cylinder is lower than 0.6 cms.

The total of all of the suds height measurements in each tes~ (i.e. until the suds height becomes lower than 0.6 cms) forms the Total Suds measurement.

One product is designated as the control and suds inde~ and suds mileage figures are calculated for the other product versus the 'control' product on the following basis.

Suds Indes of test product - Over~ll s~s of test Dro~l~ct s l00 Overall suds of control product Suds Mileage of test product - number of soil additions to test product solution to r~--~e s~ he; aht to 0.6 ~m ~ 100 number of soil additions to control product to reduce suds height to 0.6 cm The invention is illustrated in the following non-limitati~e esamples in which all parts and percentages are by weight unless otherwise specified.

209~ 19 ~ - 24 _ ExamDle 1 A range of core surfactant systems was prepared containing a misture of alkyl ethosysulphate surfactant and N-lauroyl-N-methyl glucamine. The alkyl ethosysulphate was derived from a C12-C14 primary alcohol condensed with an average of 0.8 moles of ethylene oside per mole of alcohol and neutralised with a misture of ammonium and magnesium ions so as to contain 0.22 moles of magnesium per mole of alkyl ethosysulphate. A simulated product of 30%
core surfactant concentration was first made in distilled water. A 0.12% by weight solution of this product was then formed in either soft (2 Clark) or hard (18 Clark) water and tested for IFT, and in 2 Clark water for PPC
greasy soil removal, using the test methods hereinbefore described. This procedure was followed for ratios of alkyl ethosy sulphate to alkyl glucamine of 100:0, 75:25, 65:35, 50:50, 25:75 and 0:100 and the results are shown below.

IE~ (Pa.cm) AES : GA weight ratio Water Hardness 100:0 75:25 65:35 50:50 25:75 0:100 2 0.35 0.12 0.12 0.14 0.16 0.10 18 0.21 0.09 0.07 0.12 0.06 0.07 2 1.0 - 1.6 1.5 - 1.3 2092~ 94 It can be seen that the addition of the alkyl glucamine to the anionic surfactant produces a marked improvement in grease emulsification, as shown by the IFT values, and in greasy soil handling, as shown by the enhanced PPC soil removal values.

The above co-surfactant mixtures were also evaluated for Total Suds Height and suds mileage performance using the previously described test methods. However the results were not indexed against a standard product but were reported directly as Total suds/Suds mileage figures.
AES: GA Weiqht Ratio 100:0 95:0 90:10 75:25 65:3550:500:100 Hardness 2Clark Real Meal Soil 260/5.0 344/6.5 416/7.5567/10.0 657/10.0 604/10.5 458/10.0 Greasy Soil 250/4.5 277/4.8 333/5.5 407/8.0 528/8.5 355/6.5 100/2.0 18 Clark Real Meal Soil 300/5.5 415/6.8 498/8.0 595/9.5 600/9.7 621/10.0 400/10.0 Greasy Soil 302/4.8 316/5.0 369/6.0 380/6.0 348/5.5 283/4.7 64/1.0 From a consideration of both the greasy soil removal data and the sudsing data under greasy soil loading conditions, it can be seen that a preferred range of mixtures for both grease removal and sudsing performance lies between 75 : 25 Alkyl ethoxysulphate : Alkyl glucamine and 50 : 50 Alkyl ethoxysulphate : Alkyl glucamime, with an optimum at about 65 : 35. A 100~ Alkyl glucamine system gives comparable grease removal performance but is seriously deficient in total sudsing and suds mileage particularly under greasy soil conditions.

X' .. -26-The following compositions A - E were prepared:

Composition A represents a comparative commercially available liquid detergent dishwashing product while Compositions B, C, D

& E are in accordance with the invention.

Cll 8 linear alkyl benzene sulphonate 6.5 N-Coconut alkanoyl-N-methyl glucamine - 12.5 10.0 8.0 12.8 Cl2-l3 alkyl (EO)o 8 sulphate20.5 11.015.0 16.0 10.0 Cl2-l3 alkyl (EO) 3 sulphate - - - - 2.7 Primary alcohol ethoxylatel 4.0 6.0 4.0 8.0 7.0 Mg++ ion 0.350.20 0.25 0.5 Cl2-Cl4 alkyl di methyl betaine 1.5 4.0 3.0 2.0 2.0 Coconut Monoethanolamide 3.8 Cl2-Cl4 alkyl dimethyl amine oxide - - 4.0 Sodium Cumene sulphonate 1.0 1.0 2.0 2.0 2.0 Ethanol 4.5 5.0 5.0 5.0 5.0 Urea - 5 Water -----------to 100------------1 A predominantly linear Cg-Cll blend containing an average of 10 ethylene oxide units per mole of alcohol, and containing less than 2~ by weight of unethoxylated alcohol.

X ~

_ -27- 20921 94 IFT, PPC and suds mileage values were obtained for all five products and the results are expressed below.

1. IFT (Pa.cm) A B C D E
2Clark 0.15 0.08 0.08 0.09 0.08 18Clark 0.11 0.06 0.06 0.07 0.06 2. PPC
2Clark 1 1.6 1.7 1.7 N/A

3. Total Suds/Suds Mileage Mixed soil A B C D E
2Clark 100/100 189/167 186/170 135/128 142/129 18Clark 100/100 145/140 177/153 121/119 138/150 Greasy Soil 2Clark 100/100 132/129 130/132 123/122 150/150 18Clark 100/100 95/113 98/115 108/107 102/99

Claims

Claims:

1. An unbuilt liquid or gel-form detergent composition in the form of a physically stable aqueous solution comprising from about 15% to about 65% by weight of the composition of a core surfactant mixture consisting essentially of, a) from about 5% to about 95% by weight of the mixture of least one water-soluble anionic surfactant salt selected from the group consisting of sulfates and sulfonates;

b) from about 95% to about 5% by weight of the mixture of one or more compounds having the general formula wherein Z is a polyhydroxy hydrocarbyl moiety having a linear hydrocarbon chain with at least three hydroxy hydrocarbon chain with at least three hydroxy groups connected directly to the chain, said moiety being derived from glucose and mixtures thereof with maltose, the maltose comprising not more than about 33% by weight of the mixture, R is a moiety selected from the group consisting of saturated and unsaturated alkyl groups of from about 8 to about 16 carbon atoms and mixtures of such groups and R1 is a moiety selected from the group consisting of C1-C4 alkyl and C2-C4 hydroxyalkyl groups;

whereby a 0.12% by weight aqueous solution of the surfactant mixture of said composition, in water of 2° Clark mineral hardness (Ca:Mg ratio of 3:1) and temperature of 48°C, has i) a spinning drop interfacial tension (IFT) of less than about 0.2 Pa.cm using a triolein soil of 99.7% purity;

ii) a greasy soil removal value in the Polypropylene Cup (PPC) Test of at least about 1.4 x the value obtained in the same test under the same conditions using a 0.12% solution of the?anionic surfactant component(s) alone.

2. An unbuilt liquid or gel-form detergent composition according to claim 1 wherein the polyhydroxy hydrocarbyl moiety of component b) is derived from glucose and mixtures thereof with maltose in which maltose comprises no more than about 25%
by weight of the mixture.

3. An unbuilt liquid or gel-form detergent composition according to claim 1 comprising from about 20% to about 50% by weight of the composition of the mixture of core surfactants.

4. An unbuilt liquid or gel-form detergent composition according to claim 3 comprising from about 22% to about 40% by weight of the composition of the mixture of core surfactants.

5. An unbuilt liquid or gel-form detergent composition according to claim 1 wherein the mixture of core surfactants comprises from about 20% to about 80% by weight of (a) and from about 80% to about 20% by weight of (b).

6. An unbuilt liquid or gel-form detergent composition according to claim 5 wherein the mixture of core surfactants comprises from about 40% to 70% by weight of (a) and from 60%
to 30% by weight of (b).

7. An unbuilt liquid or gel form detergent comprising in the form of a physically stable aqueous solution comprising from about 20% to about 50% by weight of the composition of a core surfactant mixture consisting essentially of a) from about 5% to about 95% by weight of the mixture of at least one water soluble anionic surfactant selected from the group consisting of C10-C16 alkyl ethoxy sulfates containing an average of up to 6 moles of ethylene oxide per mole of alkyl ethoxysulfate, C10-C18 alkyl glyceryl ether sulfonates, C10-C16 paraffin sulfonates, C9-C17 acyl N-C1-C4 alkyl glucamine sulfates and mixtures of any thereof, b) from about 95% to about 5% by weight of the mixture of one or more compounds having the general formula wherein R is a moiety selected from the group consisting of saturated and unsaturated C8-C16 hydrocarbyl groups and mixtures thereof, R1 is selected from the group consisting of C1-C4 alkyl and C2-C4 hydrocarbyl groups and Z is a polyhydroxy hydrocarbyl moiety derived from glucose and mixtures thereof with maltose in which maltose comprises no more than about 25% by weight of the mixture;

whereby a 0.12% by weight aqueous solution of the surfactant mixture of said composition, in water of 2° Clark mineral hardness (Ca:Mg ratio 3:1) and a temperature of 48°C has i) a spinning drop interfacial tension (IFT) of less than about 0.2 Pa.cm using a triolein soil of 99.7% purity;

ii) a greasy soil removal value in the Polypropylene Cup (PPC) Test of at least about 1.4 x the value obtained in the same test under the same conditions using a 0.12% solution of the anionic surfactant component(s) alone.

8. An unbuilt liquid or gel-form detergent composition according to claim 7 comprising from about 22% to about 40% by weight of the composition of the mixture of core surfactants.

9. An unbuilt liquid or gel-form detergent composition according to claim 7 wherein the mixture of core surfactants comprises from about 20% to about 80% by weight of (a) and from about 80% to about 20% by weight of (b)

10. An unbuilt liquid or gel-form detergent composition according to claim 7 wherein the mixture of core surfactants comprises from about 40% to about 70% by weight of (a) and from about 60% to about 30% by weight of (b)

11. An unbuilt liquid or gel-form detergent composition according to claim 7 wherein component a) comprises a primary C12-C14 alkyl ethoxy sulfate surfactant containing an average of no more than about 1.5 ethoxy groups per mole of alkyl ethoxysulfate.

12. An unbuilt liquid or gel-form detergent composition according to claim 7 wherein components a) comprises a primary C12-C14 alkyl ethoxy sulfate surfactant containing an average of from 0.4 to about 1.0 ethoxy groups per mole of alkyl ethoxy sulfate

13. An unbuilt liquid or gel-form detergent composition according to claim 7 incorporating Mg++ in an amount of up to about 1.5% by weight of the composition.

14. An unbuilt liquid or gel form composition according to claim 7 incorporating Ca? in an amount of up to about 1% by weight of the composition.

15. An unbuilt liquid or gel form detergent composition according to claim 7 incorporating a suds promoting material selected from the group consisting of C10-C16 alkyl mono- or di-C2-C3 alkanolamides, C12-C16 alkyl sulphobetaines, C10-C16 alkyl, di C1-4 alkyl or di C2-4 hydroxyalkyl amine oxides, C9-C2 primary alcohol ethoxylates containing an average of from 7 to 12 ethylene oxide groups per mole of alcohol and mixtures thereof.

16. An unbuilt liquid detergent composition in the form of a physically stable aqueous solution comprising from about 20% to about 50% by weight of the composition of a core surfactant mixture consisting essentially of a) from about 40% to about 70% by weight of the mixture of at least one water soluble anionic surfactant selected from the group consisting of C10-C16 alkyl ethoxy sulfates containing an average of up to 6 moles of ethylene oxide per mole of alkyl ethoxysulfate, C10-C18 alkyl glyceryl ether sulfonates, C10-C16 paraffin sulfonates, C9-C17 acyl N-C1-C4 alkyl glucamine sulfates and mixtures of any thereof, b) from about 65% to about 30% by weight of the mixture of one or more compounds having the general formula wherein R is a moiety selected from the group consisting of saturated and unsaturated C8-C16 hydrocarbyl groups and mixtures thereof, R1 is selected from the group consisting of C1-C4 alkyl and C2-C4 hydrocarbyl groups and Z is a polyhydroxy hydrocarbyl moiety derived from glucose and mixtures thereof with maltose in which maltose comprises no more than 5% by weight of the mixture;

said composition also comprising a suds promoting material comprising a betaine, and a C9-11 primary alcohol condensed with an average of from about 7 to about 9 moles of ethylene oxide per mole of alcohol, each material being present in an amount of from about 2% to about 8% by weight of the composition.

whereby a 0.12% by weight aqueous solution of the surfactant mixture of said composition, in water of 2° Clark mineral hardness (Ca:Mg ratio 3:1) and a temperature of 48°C has i) a spinning drop interfacial tension (IFT) of less than about 0.2 Pa.cm using a triolein soil of 99.7% purity;

ii) a greasy soil removal value in the Polypropylene Cup (PPC) Test of at least about 1.4 x the value obtained in the same test under the same conditions using a 0.12% solution of the anionic surfactant component(s) alone.

17. An unbuilt liquid detergent composition according to claim 16 further including a hydrotrope selected from the group consisting of C1-C3 aliphatic alcohol, urea, a lower alkyl or dialkyl benzene sulfonate and mixtures of any thereof.

18. A physically stable unbuilt liquid dishwashing detergent composition according to claim 16 wherein the composition includes an opacifier.

19. An unbuilt liquid detergent composition according to claim 16 having a pH in the range from 6.0 to 8.5.

20. An unbuilt liquid detergent composition in the form of a physically stable aqueous solution comprising from about 20% to about 50% by weight of the composition of a core surfactant mixture consisting essentially of a) from about 40% to about 70% by weight of the mixture of water soluble C10-C16 alkyl ethoxy sulfates containing an average of up to 6 moles of ethylene oxide per mole of alkyl ethoxysulfate, b) from about 60% to about 30% by weight of the mixture of one or more compounds having the general formula wherein R is a C12-C14 linear or substantially linear alkyl moiety, R1 is methyl and Z is a polyhydroxy hydrocarbyl moiety derived from glucose and mixtures thereof with maltose in which maltose comprises no more than 5% by weight of the mixture;

said composition incorporating from 0.3% to 0.5% by weight of Ca++ ion and from 0.5% to 1.0% by weight of Mg++ ion;

said composition also comprising a suds promoting material comprising a betaine, and a C9-11 primary alcohol condensed with an average of from about 7 to about 9 moles of ethylene oxide per mole of alcohol, each material being present in an amount of from about 2% to about 8% by weight of the composition.

whereby a 0.12% by weight aqueous solution of the surfactant mixture of said composition, in water of 2° Clark mineral hardness (Ca:Mg ratio 3:1) and a temperature of 48°C has i) a spinning drop interfacial tension (IFT) of less than about 0.2 Pa.cm using a triolein soil of 99.7% purity;

ii) a greasy soil removal value in the Polypropylene Cup (PPC) Test of at least about 1.4 x the value obtained in the same test under the same conditions using a 0.12% solution of the anionic surfactant component(s) alone.

21. A detergent composition comprising a mixture of nonionic and anionic detersive surfactants, wherein the nonionic surfactant is a polyhydroxy fatty acid amide and wherein the anionic surfactant is a sulfated polyhydroxy fatty acid amide which is a member selected from the group consisting of N-C9-C17 acyl-N-C1-C4 alkyl glucamine sulfates.

22. A composition according to claim 21 which additionally contains a suds-booster which is a member selected from the group consisting of alkanolamides, betaine surfactants, sulfobetaine surfactants, amine oxide surfactants, and mixtures thereof.

23. A liquid composition according to claim 21.

24. A liquid dishwashing composition according to claim 22.

25. A liquid dishwashing composition according to claim 22 which additionally contains calcium ions, magnesium ions, or mixtures thereof.

26. A method for washing dishes, comprising contacting said dishes with an aqueous bath containing a composition according to claim 21.

27. A method for washing dishes, comprising contacting said dishes with an aqueous bath containing a composition according to claim 22.