NZ240022A - Unbuilt liquid or gel-form detergent compositions comprising n-alkanoyl-n-alkyl glucamines - Google Patents

Description

New Zealand Paient Spedficaiion for Paient Number £40022 24 0 0 22 : 2r'*'c^ ?*? " I : Spe :];;,cai:on ri'oc1: .. cnov^vo vl.; . ,9>\p,>V>.2- P.-biica ion Data: 2.8. MAR 3995... j P.O. f!r.: •. - .'iW?.

NO NEW ZEALAND PATENTS ACT, 1953 No.: Date: COMPLETE SPECIFICATION LIQUID DETERGENT COMPOSITIONS IU. P.VjCtfruFFISE SEP r% r: c c i \'' i We, THE PROCTER & GAMBLE COMPANY, o corporation organized and existing under the laws of the State of Ohio, United States of America, located at One Procter & Gamble Plaza, Cincinnati, Ohio 45202, United States of America, hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- - 1 -(followed by page la) - la - LIQUID DETERGENT COMPOSITIONS Field 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.

Background of the Invention Liquid detergent compositions intended for use as dishwashing products conventionally take the £orra of aqueous solutions containing a mixture of one oc more sulphate and sulphonate anionic detergents as 'core' surfactant materials together with a suds promoting or stabilising agent. The suds stabilisation agent can take a number of forms but is normally an amide derivative, an amine oxide, an ethoxylated aliphatic alcohol, a zwitterionic surfactant such as a betaine, or a mixture 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.

One group of amide derivatives that have been suggested for suds promoting and stabilising purposes are the N-alkanoyi N-alkyl glue amines. These materials are derived from glucose and can be prepared by reacting a lower alkylarr.ine with glucose co form a glucamine and then treating this with a methyl ester of a fatty acid of the required c'-3in length to give the N-alkanoyl-N-alkyl glucamine.

Compounds of this type are taught in e.g. 'JS-A-2703798, W083/C4412 and GB-A-309060. 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 100°F particularly in Latin American countries where washing is carried out at temperatures as low as 60"F. Whilst the patent envisages that the surfactant combination can be used alone, the preferred and exemplified embodiments are granular products incorporating phosphate builder and sodium sulphate filler.

The Applicants have now discovered that unbuilt liquid or gel-form detergent compositions containing, as core surfactants, combinations of certain N-alkanoyl -N-alkyl glueamines with sulphated or sulphonated surfactants, provide a significant improvement in the reraoval of greasy soils from hard surfaces together with superior sudsing mileage performance and appreciable skin mildness benefits relative to known products. Although mixtures o£ anionic sulphate or sulphonate surfactants and H-alkanoyl -N-alkyl qlucamines 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 mixtures have, hitherto, not been recognised. 24 0 Therefore, according to the present invention/ there is provided en unbuilt liquid or gel-form detergent composition in the form of a physically stable aqueous solution comprising from 15% to 65% by weight of tha composition of a core surfactant mixture, comprising by weight of the mixture, a) froa 5% to 95% of at least one water-soluble anionic sulphate or sulphonate surfactant salt; b) froa 95% to 5% by weight of the mixture of wherein Z is a polyhydroxy hydrocarboxyl moiety having a linear hydrocarbyl chain vith at least three hydroxy group9 connected directly.to the chain, said moiety being derived froa glucose and mixtures thereof with maltose, the maltose comprising not more than SS% 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 Rx is a alkyl or C2 -C4 hydroxy alley I group; whereby a 0.12% by weight aqueous solution of the surfactant mixture of said composition, in water of 2* Clark mineral hardness (CatKg ratio of 3:1) and temperature of 48*C, has i) a spinning drop interfacial tension (ITT) of less than 0.3 Pa cm using a triolein soil of 99.7% purity? ii) a greasy soil reaoval value in ths Polypropylene cup (MC> Test of at least 1.4 x the value obtained in the saae test under the sane conditions using a 0.12% solution of the anionic surfactant component(s) alono. one or nore compounds having tha general formula R-COH Rx ?4 fl rt o " ( . / z J* ?or the purposes 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 21*C. 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 is 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 giucamines are to be construed as material including up to 5% by weight of the corresponding material derived from maltose.

Suitable anionic sulphate or sulphonate surfactants include C10~C16 alkyl ethoxy sulphates containing an average ot up to 6 moles of ethylene oxide per mole of alkyl ethoxysulphata, C10-Clg paraffin sulpiionates, and N-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 tha composition of a primary c12"ci« *1X?1 ethoxy sulphate stock containing an average of from 0.4 to 4.0 ethylene oxids groups per mole of cl2~ci4 alXyl ethoxy sulphate, preferably from 0.3 to 3.0, together with from 9% to 1S% by weight of the composition of N-cooonut acyl-N-msthyl glueamine.

Preferred compositions employ an anionic surfactant to glucamine weight ratio of between 2:1 and Hi.

Particularly preferred compositions contain from 10% to 18% 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 oontaining an average of approximately 0.8 moles of ethylene oxide/mole and material containing an average of approximately 3.0 moles of ethylene oxide/nole in a weight ratio of between 2:1 and 5:1 preferably approximately 4:1.

Preferably compositions in accordiance with the invention also contain l%-8%, most preferably 2%-7% by weight cf a suds booster selected from C10-C16 alkyl mono or di-Cj-C^ alkanolamides, ci2*C14 or amido betaines, C12-Cl 4 alkyl sulphobetaines, C1Q-C16 alkyl Si Cj-C* alkyl or di C2-C4 hydroxyalkyl amine oxides, ^9~ci2 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 C^-c^ alkyl betaine, in aa amount of from 1% to 5% preferably from l.S% to 3% by weight of the composition, together witb Cj-Cu primary alcohol ethoxylate (preferably cl0 alkyl eo8) in an amount of froa «% to 8% by weight of the composition.

Another prcforred component of aruch compositions is Kg**, at a level of up to i.s* 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. 24 0 0 2? %r-r j. ^ Description of the Invention Detergent compositions in accordance with the present invention comprise a mixture of core surfactants in an amount of from 15* to 65% by weight of the composition, preferably from 20% to 50\ and more preferably frora 22% to 40* by weight. The mixture comprises from 5* to 95* by weight of the mixture of at least one water-soluble anionic sulphate or sulphonate surfactant salt together with from 95* to S* by weight of the mixture of a rf-Cg-C,g acyl-N-C^-C^ alkyl glucamine nonionic surfactant.

Preferably the mixture comprises from 20* to 80* of the anionic surfactant and from 80* to 20* of the alkyl glucamine, and most preferably from 40* to ?0* anionic surfactant and from 60* to 30* alkyl glucamine.

The anionic surfactant can essentially bo any organic sulphate or sulphonate surfactant salt but is usually selected from C^-C^g alkyl benzene sulphonates, ~13"<'16 sulphates and their ethoxy analogues containing up to six moles of ethylene oxide per mole of alkyl ethoxy sulphate, paraffin sulphonates C10"C16 sulphonates, C^q-Cjq alkyl glyceryl ether sulphonates, C5~C17 acyl-N-C^-C^ alkyl or C2~C4 hydroxyalkyl glucamine sulphates and mixtures of any of the foregoing. Preferably the anionic surfactant is selected from alkyl ethoxy sulphates, alkyl glyceryl ether sulphonates and paraffin sulphonates.

Alkyl benxene aulphonataa 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-phenyl isomer content are preferred. 2 4 0 0 2 2 Suitable aikyl 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. C.^-C^ alcohols, derived frora natural fats, or Ziegler olefin build-up, or OXO synthesis, fcrm suitable sources for the alkyl group. Examples of synthetically derived materials include Dobanol 23 (RTM) sold by Shell Chemicals (UX> Ltd., Ethyl 24 sold by the Ethyl Corporation, a blend of C,3~C13 alcohols in the ratio 67% c13, 33% C15 sold under the trade name Lutensol by BASF GmbH and Synperonic (STM) by ICI Ltd., and Lial 125 sold by Liquichimica Italians. Examples of naturally occurring materials from which the alcohols can be derived are coconut oil and palm kernel oil and the rorresponding fatty acids.

Alkyl ethoxy sulphate surfactants comprise a primary alkyl ethoxy sulphate derived frora the condensation product of a c1(j-c,g alcohol with an average of up to 6 ethylene cxida groups. The alcohol itself can be obtained from any of the sources previously described for the alkyl sulphate component. ci2~ci3 a*kyl et^er 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 t2 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 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 coap©»itions in accordance with the present invention a mixture of alkyl ethoxy sulphates is used, combining material having an average degree of ethoxylation froa Z 4 0.4 to i.3, more preferably approximately 0.8, with naterial having an avarage degree of ethoxylation of froa 2.0 to i.O more preferably approxiaately 3.0.

Secondary alkar.e sulphonates useful in the present invention have from 13 to 18 carbon atoms per molecule, re re desirably 13 to 15 atoms per molecule. These snlphor.ates are preferably prepared by subjecting a cut o? paraffin, corresponding to the chain lengths specified soove, to the action of sulphur dioxide and oxygen in accordance with the well-known sulphoxidation process. The product o£ 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. oy the sulphochlorination method in which chlorine and sulphur dioxide are reacted with paraffins in the presence of actinic light, tha resulting sulphonyl chlorides being hydrolysed and neutralized to form the secondary alkyl sulphonates. Whatever technique is employed, it is normally desirable to produce the sulphonate as the mono6ulphonate, 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 Cl4-C1j paraffins in the range frora 1:3 to 3:1. ^ 4 0 p J $ ' *"■ fh.

Olefin sulphonates useful in the present invention are mixtures of. alkene-i-suiphonates, alkene hydroxysulphcr.ates, alkena disulphor.ates and 'nydroxydisulphonates and are described in the commonly assiqned US-A-3332880 issued to P.F. Pflaumer & A. Kessier on July 25 1967.

Suitable alkyl glyceryl ether sulphonates are tnsse derived Erorr. ethers of coconut oil and tallow.

Other sulphate surfactants include the N-Cp-Ci7 acyi-N-C^-C^ alkyl glucamine sulphates, preferably those in which the C?-C17 acyl group is derived from coconut or palm kernel oil. These materials can be prepared by the method disclosed in US-A.-2717894.

The counter ion for the anionic surfactant component can be any one of sodium, potassium, magnesium, ammonium or alkanol-aaaonium or a mixture thereof. For liquid compositions of the invention, sodium is the preferred counter ion but potassium is preferred over sodium where it is of importance that the compositions of the invention are completely clear and have a high resistance to precipitate formation.

In gel-form compositions of the invention, sodium is preferred over potassium or ammonium for the purposes of forming a gel. Preferred liquid detergent compositions in accordance with the invention have a chill point less than 8*C preferably less than 5°C, and are at least partially neutralised by ammonium ions. - 24 f; f) 9 Where calcium and/or magnesium ions are present they can either be introduced as the oxide or hydroxide to neutralise the surfactant aeid or can be added to tlx* composition as & 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 oooling 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 l% ca++ by weight of the composition, more preferably from 0.3% to 0.5% Ca++ and up to 1.50% Mg++, more preferable from o.s% to 1.0% by weight. The preferred mixtures are rich in magnesium and more preferably provide a Ca++:Ug++ weight ratio of froa 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 wherein Z is a polyhydroxy hydrocarbyl moiety having a linear hydrocarbyl chain with at least three hydroxy groups 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 auch groups* and Rj is a alkyl or C2-C4 bydroxyl alkyl group. *1 R R may be derived from any of the sources of hydrooarbyl groups discussed hereinbefore with reference to the anionic surfactant but is preferably natural in origin.

Preferably R has an average chain length of frcra 12 to 14 carbcn atoms and is derived frora coconut cil cr pain 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 ha3 two principal steps. The first step involves reacting glucose anfl a primary alXylamine in the presence of hydrogen and a hydrogenation catalyst under elevated temperature and pressure to form glucamine. This is then reacted with an 83ter at elevated temperature to form the N-alkanoyl -N-aixyl glucamine. It has been found advantageous to add a low level of sodium methoxide as a catalyst in this second step.

Preferred levels of the N-alkaaoyl -N-alkyl glucamine in liquid and gel-form composition* 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 ionB in the absenoe of magnesium iona, but require the usb of N-alkanoyl -N-alkyl glucamines of high purity in whiofe the levels of unreacted starting materials, impurities and by-products, particularly fatty acids, are minimised. in th« broadest aspect of the invention the balance of the liqruid 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 surfaetant(a) and glucamine components lie in the range from 20% to 40%, more preferably froa 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 by weight of the composition.

Certain of these materials also have additional functional value as e.g. soil suspending agents. One such suds promoting agent is a C1Q-C16 alkyl mono- or di-C.-C3 alkanolamide, examples including coconut alkyl T.onoethanol amide, coconut alkyl diethanolamide and palm kernel and coconut alkyl raonc-and di-isopropanol amides. The palm kernel or coconut alkyl residue may either be 'whole cut", including the C1Q and C1g fractions or may be the so-called 'narrow-cut' C,,-C,. fraction, Synthetic sources of the cio"cxg alkyl group can also he used.

Another useful suds promoting agent is a zwitterionic surfactant of general formula ?2 ri - (y)n - ««■ - (r3)tnx-*2 wherein R]_ is C].q-c16 alkyl, R2 is C3.-C3 alkyl, • OH R3 is a -(CH2>3 group or a -(CH2-&* - CHj) group, 0 Y is - C - | - (CH2>3 n & m are 0 or 1, and X" is CH2COO- or SO3; provided that where X" is CH2CQO"", m is 0, and where X~ is S03, n is 0 and ra is 1.

More preferably has an average carbon chaxa lengtn 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 Synthetic sources for the group may be the «aoe as those mentioned previously for the alkyl group in the anionic surfactant component. ? / o n •) A further class of suds promoting agents useful in the invention are the amine oxides of general formula rxr2r,n *o wherein R^ is an alkyl group containing from 10 to 16 carbon atoms and and R^ are each independently selected from alkyl and Cn-C, hydroxy alkyl groups. Preferred members of this c.ass include dimethyldodecyl amine oxide, dimethyl tetradecyl amine oxide, bis-<2 hydroxyethy1) dodecylamine oxide and analogues thereof in which the dodecyl or tetradecyl moiety is derived frora 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 al iphatic alcohol ethoxylate containing an average of from 1.5 to 25, more preferably from 2 to IS and most preferably frora 6 to 10 moles o£ ethylene oxide par raola 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 3 moles of athylene 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 sthylene 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 products of Ziegler olefin build up reactions or 0X0 synthesis may all be used as the source of the hydrocarbon chain, the structure of which may be linear or branched in type. 24 0Q 2 The preferred aicohol chain length range is from Cg to as it has been found that tha sudsing volume and mileage performance of compositions in accordance with the invention is optimum when incorporating ethoxylates made frora 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 il.o to is.o. A preferred alcohol etfcoxylato is a priaary alcohol ethoxyl&ta containing an average of 10 carbon atoms in the alkyl chain/ condensed with an average of a ethylene oxide groups per aole 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 Eay of 6 results in a distribution of ethoxylate speciea which ranges from 1 to 15 moles of ethylene oxide par mole of alcohol. An increase in E O V causes some change in this distribution, principally a reduction in the level of unethoxylated material, but an increase in E from 3 to 5 will still leave 5V approximately 5-10% of such material in the ethoxylated product. 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 cdour 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 toleratad 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. 24 ft u 9 - I5. - oistiilation under vacuum is employed to remove the undesired material and this also removes a portion of the monoethoxylate fraction, thereby increasing the E_ c£ the remaining material. In preferred embodiments of -he invention the level of monoethoxylate is not more than 5\ by weight of the ethoxylated alcohol.

In preferred compositions in accordance with the invention, combinations of the suds modifiers or promoters are used, each being present at a level of froa 1% to 10* nore preferably from 2% to 3% by weight. One such preferred combination is a ci2""ci4 dimethyl betaine and a Cg-C1, alcohol condensed with an average of frora 7 to 3 soles of ethylene oxide per mole of aleohol, each material being present in an amount of froa 2% to 8% by weight of the composition.

In preferred compositions the balance of the formula comprises a hydrotrope-water system in which the hydrotrcpe may be urea, a ^i"C3 aliphatic alcohol, a lower alkyl or dialkyl benzene sulphonate salt such as toluene sulphonate, xylene sulphonate, or cumene sulphonate, or mixtures of any of these. Normally a single hydrotrope will be adequate to provide the required phase stability, but compositions in accordance with the present invention preferably employ a mixture such as urea-alcohol-water, alcohol-lower alkyl benzene sulphonate-water or urea-lower alkyl benzene sulphonate-water in ordec co achieve the desired viscosity, and to remain stable and easily pourable. For compositions having an organic active ■ - ■ : 9 - 16 _ concentration less than about 40% by weight, tha 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 ir. admixture with urea. For compositions havinq an organic active concentration greater than about 40% by weight, .nixtures of ethanol with urea ar.<J/or lower alkyl benzene sulphonates are preferred. Mixtures of hydrotropes can, of course, be employed for c-st effectiveness reasons irrespective of any stability/viscosity considerations. optional ingredients of tha liquid detergent compositions of the invention include opacifiers such as ethylene glycol cistearate, thickeners such as guar gum, antibacterial agents such as glutaraidehyde and Bronopol (3TM), sntitarnish agents such as benzoxytriazole, heavy raetal chelating agents such as ETDA or ETDKP, 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 -o 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. 24 0 0 2 i. ' The ccrr,positions cf the invention can be made m a number cf ways but it is preferred that any switterionic surfactant included therein is incorporated cowards the end cf the rr.aking process if not actually forming the last ingredient to te added. This minimises the risk of any degradation cf the zwitterionic surfactant under the acid conditions existing at the beginning of the making process and also facilitates the control of the viscosity cf 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 he made as aqueous solutions of alkali metal or ammonium salts with pH adjusted between <J and 10 which are then mixed together with che 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 avitterionic 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 ethoxylate can be mixed together and a single sulphation and neturalisatlon can then bo carried out on these two materials. For this, the alcohol and alcohol ethoxylate should be nixed in a weight ratio lying in the range from 4t3 to l:6. Zn tha most preferred technique A 9 however, a single alcohol ethoxylate stock is produced in which the levels cf alcohol and ethoxylated alcohol species are controlled to provide the desired ratio of these starting materials.

Suiph(on)ation of the alcohol and alcohol ethoxylate can employ any of the conventional sulph(on)ating agents such as sulphur trioxide or chlorosulphonic acid.

Neutralisation of the alkyl ether sulphuric acid and the alkyl sulphuric acid is then carried out vith the appropriate allcali or with a magnesium, oalciua or magnesium/calcium oxide or hydroxide slurry. If the amount of anionic surfactant is not suffioient to permit all of the desired Ca"H' and/or Kg** ions to be added in this way, the remainder oan then be added in the form of a vatar soluble salt. Where mixtures of oaleiua and magnesium salts are added, the anion of the Magnesium salt should be selected so that the corresponding calcium salt is also water soluble.

Gel compositions of the present invention can be prepared using the general method described in US Patent No. 4615819.

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 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 compositions.

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. 2 4 0 r2 2 -J Interfacial Tension <ITT) Measurement of IFT gives an indication of the ability of * surfactant saaple to enulsify a soil under a defined set of conditions. ZFT wis determined by means of a spinning Drop Tenaioneter and a University of Texas Model soo manufactured by the University of Texas, Austin, Texas, USA. Two instruments were employed, vis. a Model SITE 04, manufactured by Krttss GobH wissensaaftliche Labcrgerate, Sorsteler chaussee 83-99a, d2000 hajnburg €1 frg under conditions representative of thoso encountered in Europen manual dishwashing practice. Thus, measurements were aade at a sample temperature of 48°C t 1*C 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) supplied by aldrich Chemical Company Ltd. New Road, Gillingham, Dorset, England. Results were quoted in Pa cm (IPa cm = 10 dynes/cm). 2) Polypropylene Cup weight loss (PEG).

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) * liquid 100* corn oil (MAZZOLA manufactured by CPC(UK) Ltd., Claygate House, Esher, Surrey, England) 24 0 0 The mixture is boated until it becomes aiscible,after which it is cooled and stored at a temperature <0*C. For use, approximately ISO Ql of fat is melted in a glass beaker and held at to 75"C. Fifteen 250 ml clean, dry, polypropylene TRIPOUR -ups are each weighed and 6.00 t 0.03g fat are weighed into each by pouting directly into the base of the cup without spillage cn 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 I 1*C.

A 0.12% solution of the test product is prepared at 50-559C and 100 t o.ig 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 45-46'C such that the solution in each jar is at a temperature of 43.3 t 0.1°C. a similar procedure is followed for each product under test as well as for tha 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 21°C before being transferred to an ice bath and held tor 10 minutes.

Jpon 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.

A£ter 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 24 n A cup is then stood upside down on absorbent kitchen roll to dr3in for 10-15 minutes before being dried in an oven for two hours ac 30°C followed by a further hour at 50"C. The cups are then reweighed. An average weight difference between the original weight of fat and that remaining after the test ia calculated Eor 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 performance 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 veight ratio of the liquid and solid fat serving as the soil composition so that the standard (reference) product provides 2 0-3 5% fat removal under the conditions of the test vhile the test product can have a Cat removal of £rom 20 to 80%. The same batch of fat must be used for the test and reference products. 3) Tstai Suds and suds Mileage Total suds is the total volume of suds generated during a standard dishwashing test and is a measure o£ the perceived foaming ability of the formulation. Suds mileage is a measurement of the soil loading required to reduce the suds of a teat 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 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. lest Conditions, Product Concentration 0.12% water Temperature 4ft*c water Hardness 2*Clark and 18°Clark 9 a... ?? - f.gOfl SQAi Rice/Tiir.ce/Egg "Seal Meal" 1 r 292g Tin lyne Brand Minced Beef & Onion1 2 1 * 43Sg Tin Ambrosia Creamed Rice Pudding 1 Egg mis 2\ Mixed Free Fatty Acid (MFFA) in Corn Oil* mis Corn Oil Greasy Soil Cake Mix Slurry 30g Sponge Mix3 6Cg 2% MFFA in Corn Oil* 1 Marketed by Master Foods, Kings 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.

The method uses 4 cylinders of length 30 cm and diameter 10 era fixed side by side, and rotatable at a speed of 24 rpm about a central axis. Each cylinder Is charged with 500 mis cf product solution at a concentration of 0.12% and a temperature of 48*C. The outer two cylinders are used foe one of tha products being compared and the inner two for the other product. 2 4 n n ? - :3" - 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 1 minute the cylinders die restarted and allowed to rotate for 1 minute. The suds height is noted and 2 mis of the soil is added to each cylinder. After 1 minute the cylinders are restarted.

This process continues until the suds height in the cylinder is lower than C.6 ctis.

The total of ail of the suds height measurements in each test? (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 index and suds mileage figures are calculated for the other product versus the 'control' product on the following basis.

Suds Index of test product - Overall suds of test product x 100 Overall suds of control product Suds Mileage of test product = number of soil additions to test product solution r.o reduce suds height to 0.6 cm x 100 number of soil additions to control product to reduce suds height to 0.6 eta The invention is illustrated in the following non-limitative examples in which all parts and percentages are by weight unless otherwise specified. 9 / C o 2« - Zsarrple 1 A range of core surfactant systems was prepared containir.q a mixture of alkyl ethoxysulphate surfactant and N-lauroyl-N-rcethyI glucamine. The alkyl ethoxysulphate was derived from a ci2~ci4 priory alcchol condensed with an average cf 0.8 moles of ethylene oxide per mole of alcohol and neutralised with a mixture of ammonium and magnesium ions so as to contain 0.22 moles of magnesium per mole of alkyl ethoxysulphate. 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 ethoxy sulphate to alkyl glucamine of 100:0, 75:25, 65:35, 30:50, 25:75 and 0:100 and the results are shown below.

I FX (?a.cm) AES : GA weight ratio Water Hardness 10C:0 75:25 65:35 50:50 25:75 0:100 2a 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 PPC 2* 1.0 1.6 1.5 1.3 o k.' 'i o : t can be seen that the addition o£ the alkyl ;lucarr.ine tc the eiioric suifactant produces a marked improvement in grease er.jlsif ication, as sr.cwn by the I FT values, end in greasy scii ".a.-cling, as shown by the enhanced F?C soil removal values.

The above co-surfactant mixtures were also evaluated for Total Suds Height and suds mileage perforir.ance using Lhe previously Described test methods. However the results were not indexed against a standard product but were reported directly as Total suds/Suds mileage figures.

Ji£S: GA ttoight Ratio 100:0 9 5: S 90:10 75:25 65:35 SO:SO 3:100 Hardness 2'Clsrk Real K#«l SOU 260/5.0 344/6.5 4X4/7.J 567/10.C 657/10.0 604/10.5 <58/10.0 Creasy soil 230/4.5 277/4.a 333/3.) <07/8.0 526/6.5 355/6.5 100/2.0 19'CltrH R»»l naal Soil 300/5.3 415/6.S 496/4.0 595/9.S 600/9.7 631/10.0 400/10.0 Greisy Soil 302/4.3 316/5.0 369/6.0 360/6.0 141/5.5 263/4.7 64/1.0 Frora 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 t Alkyl glucamine and SO : 50 Alkyl ethoxysulphate : Alkyl glucamine, with an optimum at about 65 t 35. A 100% Alkyl glucamine system gives comparable grease removal performance but is eeriously deficient is total sudsing and suds mileage particularly under greasy soil conditions. 2 4 C: 0 p ■ ■' ^ c EXAMPLE 2 The following compositions A - E were prepared: composition A represents a comparative comnercially available liquid detergent dishwasfcing product *hile compositions B, C, d & £ are in accordance with the invention, C1< g linear alKyl tenmne S'jljhonate S-S - - " H-Cocoaut alkanoyl-K-methyl jlucwuin* - 12 • 5 10.0 3.0 12.* C12-U 3l>tyl .5 11.0 15.0 11.0 10.0 S.' (EO)j 8 suipnate c12-13 al*?1 <B0)j sulphate primary alcohol ethoxylate* 4.0 6.0 4.C i.o 7.0 M9** is n 0.3S 0.20 0.25 3.3 '*12~<"i4 alkyl di ®ethyl betiln*. l.S 4.0 3.0 2.0 2.0 coconut Kono«thanoleaide 3.8 - - - C12"CI4 d1 amine oxide - - 4.0 - - Sodiuj* cuaen« sulphonate l.o i.o 2.0 2.0 2.0 itisanoi *.3 urea 0.3 - - - water —-to 100 A predominantly linear C^-C^ blend containing an average of 10 ethylene oxide units per mole o£ alcohol, and containing less than 2% by weight of unethoxylated alcohol.

Claims (21)

IFT, PPC and suds .mileage values were obtained for all five products and the results are expressed belov. IFT (Pa.cn) 2°CLar* 13*Clark A 0.15 0.11 B 0.08 0.06 C D 0.08 0-09 0.06 0.07 £< 0.08 0 . 08 PPC 2°Clark 1.6 1.7 1." N/A Total suds/suds Mileaq® Mixed soil 2°Clark 18°clarX ABC D 100/100 189/167 186/170 135/128 100/100 145/140 177/153 121/119 E 142/125 138/150 Greasy Soil 2°Clark 100/100 132/129 130/132 123/122 18"Clark 100/100 95/113 98/115 108/107 150/150 102/99 24 0 02 28 WHAT f/WE CLAIM IS i

1. An unbuilt liquid or gei-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 consisting essentially of, a) from 5% to 95% by weight of the mixture of at least one water-soluble anionic surfactant salt selected from the group consisting of sulfates and sulfonates: b) from 95% to 5% by weight of the mixture of one or more compounds having the general formula R-CON — Ri wherein Z is a polyhydroxy hydrocarbyl moiety having a linear hydrocarbon chain with at least three hydroxy groups connected directly to the chain, said moiety being derived from glucose or a mixture thereof with maltose, the maltose comprising not more than 33% by weight of the mixture, R is a moiety selected from the group consisting of saturated and unsaturated alkyl groups of from 8 to 16 carbon atoms and is a moiety selected from the group consisting of C^-C^ alkyl and C2-C4 hydroxyalkyl groups; "* 1 DEC m 24 0 0 29 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 0.2 Pa .cm using a triolein soil of 99.7% by weight purity; ii) a greasy soil removal value in the Polypropylene Cup (PPC) Test of greater than 1.3 x the value obtained in the same test under the same conditions using a 0.12% by weig solution of the anionic surfactant component(s) alone.

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

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

An unbuilt liquid or gel-form detergent composition according to claim 3 comprising from 22% to 40% by weight of the composition of the mixture of core surfactants. NZ ! - 1 DEC 1SS'i 24 0 02 2 30

An unbuilt liquid or gel-form detergent composition according to claim 1 wherein the mixture of core surfactants comprises from 20% to 80% by weight of (a) and from 80% to 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 40% to 70% by weight of (a) and from 60% to 30% by weight of (b).

7. An unbuilt liquid or gel form detergent composition in the form of a physically stable aqueous solution comprising from 20% to 50% by weight of the composition of a core surfactant mixture consisting essentially of from 5% to 95% by weight of the mixture of at least one water soluble anionic surfactant selected from the group consisting of C10-C16 a'ty1 ethoxy sulfates containing an average of up to 6 moles of ethylene oxide per mole of alkyl ethoxysulfate, C10-C18 alkyl glyceryl ether sulfonates, C1Q-C16 paraffin sulfonates, C9-C17 acyl N-C1-C4 aJkyi glucamine sulfates and mixtures of any thereof. from 95% to 5% by weight of the mixture cf one or more compounds having the general formula R-CON — R1 ■>) 24 0 31 wherein R Is a moiety selected from the group consisting of saturated and unsaturated Cs-Cig hydrocarbyl groups, R^ is selected from the group consisting of -C4 alkyl and C2-C4 hydrocarbyl groups and Z is a polyhydroxy hydrocarbyl moiety derived from glucose or a mixture thereof with maltose in which maltose comprises no more than 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 of 3:1) and a temperature of 48aC has I) a spinning drop interfacial tension (IFT) of less than 0.2 Pa.cm. using a triolein soil of 99.7% by weight purity; ii) a greasy soli removal value in the Polypropylene Cup (PPC) Test of at least 1.4x the value obtained in the same test under the same conditions using a 0.12% by weight solution of the anionic surfactant component(s) alone.

An unbuilt liquid or gel-form detergent composition according to claim 7 comprising from 22% to 40% by weight of the composition of the mixture of core surfactants. 13. *4 0 022 32

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

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

An unbuilt liquid or gel-form detergent composition according to claim 7 wherein component a) comprises a primary C-(2-C14 alkyl ethoxy sulfate surfactant containing an average of no more than 1.5 ethoxy groups per mole of alkyl ethoxysulfate.

An unbuilt liquid or gel-form detergent composition according to claim 7 wherein component a) comprises a primary Ci2-C-)4 alkyl ethoxy sulfate surfactant containing an average of from 0.4 to 1.0 ethoxy groups per mole of alkyl ethoxy sulfate.

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

An unbuilt liquid or gel form composition according to claim 7 incorporating Cat + In an amount of up to 1 % by weight of the composition. - i dec m U 0 33

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 mono- or di- Cp C3 alkanolamides, C-i 2-C-j 6 alkyl sulphobetaines. Ciq-Ciq alky!, di C1-4 alkyl or di C2-4 hydroxyalkyl amine oxide3, C9-c12 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 20% to 50% by weight of the composition of a core surfactant mixture consisting essentially of a) from 40% to 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, Ct0-Ci6 paraffin sulfonates, C9-C17 acyl N-C1-C4 alkyl glucamine sulfates and mixtures of any thereof .• b) from 60% to 30% by weight of the mixture of one or more compounds having the general formula R-CON — R! 24 34 wherein R is a moiety selected from the group consisting of saturated and unsaturated Cq-Ci6 hydrocarbyl groups, is selected from the group consisting of C1-C4 alkyl and C2-C4 hydrocarbyl groups and Z is a poly hydroxy hydrocarbyl moiety derived from glucose or a mixture 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 Cg_i 1 primary alcohol condensed with an average of from 7 to 9 moles of ethylene oxide per mole of alcohol, each material being present in an amount of from 2% to 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 of 3:1) and a temperature of 48°C has i) a spinning drop interfacial tension (IFT) of less than 0.2 Pa.cm. using a triolein soil of 99.7% by weight purity; ii) a greasy soil removal value in the Polypropylene Cup (PPC) Test of at least 1.4x the value obtained in the same test under the same 2 4 0 0 35 conditions using a 0.12% by weight solution of the an 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 20% to 50% by weight of the composition of a core surfactant mixture consisting essentially of a) from 40% to 70% by weight of the mixture of water soluble C-|0"Cl 6 a,kYl ethoxy sulfates containing an average of up to 6 moles of ethylene oxide per mole of alkyl ethoxysulfate, b) from 60% to 30% by weight of the mixture of one or more compounds having the general formula R-CON R-| v. •Z NZ P'.' - 1 D£C o 36 wherein R is a Ci 2^14 linear or substantially linear alkyl moiety, R1 is methyl and Z !s a polyhydroxy hydrocarbyl moiety derived from glucose or a mixture 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 7 to 9 moles of ethylene oxide per mole of alcohol, each material being present in an amount of from 2% to 8% by weight of the composition whereby a 0.12% by weight aqueous solution of the surfactant mixture of said composition, in water of T Clark mineral hardness (Ca:Mg ratio of 3:1) and a temperature of 483C has i) a spinning drop interfacial tension (IFT) of less than 0.2 Pa.cm. using a triolein soil of 99.7% by weight purity; ii) a greasy soil removal value in the Polypropylene Cup (PPC) Test of at least 1.4x the value 2*0 02 obtained in the same test under the same conditions using a 0.12% by weight solution of the anionic surfactant component(s) alone.

21. An unbuilt liquid or gel-form detergent composition in the form of a physically stable aqueous solution according to any one of claims 1, 7, 16 and 20, and substantially as herein described with reference to any embodiment disclosed in the examples. : * /'■. . PC" ftGENWC?: '\>vl mts