CA2292967A1 - A water-based multiphase cleaning composition - Google Patents

Abstract

A water-based liquid, multiphase surfactant-containing cleaning composition with at least two continuous phases, which contains at least one lower aqueous phase I and an upper aqueous phase II immiscible therewith, can be temporarily converted into an emulsion and contains citric acid and/or at least one citrate, may be used to clean hard surfaces and may be prepared by mixing directly from its raw materials, subsequent intermixing and, in a final step, allowing the composition to stand for separation of the temporary emulsion, citric acid and/or at least one citrate being used as phase separation auxiliary and/or for reducing clouding in the vicinity of the boundary layer between phases I and II in a water-based liquid, multiphase surfactant-containing cleaning composition with at least two continuous phases, which contains at least one lower aqueous phase I
and an upper aqueous phase II immiscible therewith and which can be temporarily converted into an emulsion by shaking, or being used in a process for the production of such a cleaning composition.

Description

A Water-based Multiphase Cleaning Composition This invention relates to water-based, multiphase, liquid surfactant-containing cleaning compositions containing citric acid or citrate which can be temporarily emulsified by shaking and which may be used to clean hard surfaces, to a process for their production and to their use for cleaning hard surfaces and to the use of citric acid or citrate in this multiphase cleaning composition as a phase separation aid or for reducing clouding in the vicinity of the boundary layer between the phases and to corresponding processes for the production of such multiphase cleaning compositions using citric acid or citrate for phase separation or for reducing the clouding mentioned above.
Universally usable cleaning compositions for all wet-wipe or damp-wipe surfaces in the home and in the institutional sector are known as so-called multipurpose cleaners and represent predominantly neutral to weakly alkaline water-based liquid products which contain 1 to 30% by weight of surfactants, 0 to 5% by weight of builders (for example citrates, gluconates, soda, polycarboxylates), 0 to 10% by weight of hydrotropes (for example alcohols, urea), 0 to 10% by weight of water-soluble solvents (for example alcohols, glycol ethers) and optionally inter alia skin-care agents, dyes and fragrances. Corresponding cleaners are generally used in the form of an approximately 1 % solution in water, although they may even be used in undiluted form for local stain removal. In addition, ready-to-use multipurpose cleaners are marketed as so-called spray cleaners.
The water-based liquid cleaners in question are normally present as homogeneous stable solutions or dispersions. However, the effect of using certain, more particularly hydrophobic, components in such cleaning compositions can be that this homogeneity is lost and inhomogeneous compositions with very little consumer appeal are obtained. In cases such as these, there is a need for the alternative formulation of compositions which, despite their inhomogeneity, have a defined appearance acceptable to the consumer and are user-friendly.

European patent application 116 422 describes a liquid hair or body shampoo comprising two aqueous phases which can be temporarily dispersed in one another by shaking and which are both miscible with water in any ratio. The upper phase contains 8 to 25% by weight, based on the composition as a whole, of at least one surfactant while the lower phase contains at least 6% by weight, based on the composition as a whole, of dissolved sodium hexametaphosphate corresponding to formula I' ONa ONa ONa Na0-P-O P-O P-ONa (I) o ° ~ ,".~
in which n has an average value of about 12. The lower phase may optionally contain other builder salts. The surfactants present may be anionic, cationic, amphoteric and/or nonionic surfactants, at least one anionic surfactant preferably being present.
DE-OSS 195 01 184, 195 01 187 and 195 01 188 (Henkel KGaA) relate to hair treatment compositions in the form of a two-phase system which comprise an oil phase and a water phase, the oil phase being based on silicone oil or paraffin oil, and which can be mixed in a short time by mechanical action.
In the case of a two-phase composition, such as that known from European patent application 116 422, unwanted clouding of the individual phases in their non-dispersed separated state can readily occur, particularly after shaking one or more times. Streak-like clouding can occur, above all in the vicinity of the boundary layer. Such clouding is unattractive to the consumer and can even be misinterpreted as a sign of a product which has become unusable. In addition, renewed phase separation may occur only partly, if at all, after shaking one or more times, leading to an undefined appearance of the product which does not appeal to the consumer.

The problem addressed by the present invention was to provide high-performance storage-stable compositions for cleaning hard surfaces in a defined inhomogeneous, easy-to-handle form acceptable to the consumer which would not have any of the problems described above.
In a first embodiment, the present invention relates to a water-based, liquid, multiphase, surfactant-containing cleaning composition with at least two continuous phases which contains at least one lower aqueous phase I and an upper aqueous phase II immiscible therewith, which can be temporarily converted into an emulsion by shaking and which contains citric acid and/or at least one citrate.
In a second embodiment, the present invention relates to the use of a water-based, liquid, multiphase, surfactant-containing cleaning composition with at least two continuous phases, which contains at least one lower aqueous phase I and an upper aqueous phase II immiscible therewith, which can be temporarily converted into an emulsion by shaking and which contains citric acid and/or at least one citrate, for cleaning hard surfaces.
In a third embodiment, the present invention relates to a process for the production of a composition according to the invention by mixing directly from its raw materials, subsequent intermixing and, in a final step, leaving the composition to stand for separation of the temporary emulsion.
In a fourth embodiment, the invention relates to the use of citric acid and/or at least one citrate in a water-based, liquid, multiphase, surfactant-containing cleaning composition comprising at least two continuous phases, which contains at least one lower aqueous phase I and an upper aqueous phase II immiscible therewith and which can be temporarily converted into an emulsion by shaking, as a phase separation auxiliary and/or for reducing clouding in the vicinity of the boundary layer between phases I and II.
In a fifth embodiment, the present invention relates to a process for the production of a water-based, liquid, multiphase, surfactant-containing cleaning composition with at least two continuous phases, which contains at least one lower aqueous phase I and an upper aqueous phase II
immiscible therewith and which can be temporarily converted into an emulsion by shaking, characterized in that citric acid and/or at least one citrate is used as a phase separation auxiliary and/or for reducing clouding in the vicinity of the boundary layer between phases I and II.
In the context of the present invention, "temporarily" is understood to mean that 90% of the separation of the emulsion formed by shaking into the separate phases takes place in 2 minutes to 10 hours at temperatures of about 20°C to about 40°C, the final 2% of the separation into the phase state before shaking taking place over another 15 minutes to 50 hours.
According to the present invention, it is possible - unless otherwise expressly stated - to use a salt and, with equal effect, the corresponding acid/base pair of the salt which is only formed in situ through neutralization of the salt or its solution, even if the particular alternative is not always explicitly mentioned in the present teaching. Accordingly, potassium citrate for example and the citric acid/potassium hydroxide combination or potassium alkyl benzenesulfonate and the alkyl benzenesulfonic acid/potassium hydroxide combination represent equivalent alternatives.
Insofar as the following observations relate to one of the subjects of the invention, they apply equally to the other subjects of the invention, unless otherwise specifically stated.
According to the invention, citric acid or citrate advantageously combine building and phase-separation promoting properties. Accordingly, the compositions according to the invention are distinguished by high cleaning performance in diluted and undiluted form, particularly against obstinate fatty soil in undiluted form. In addition, the compositions according to the invention show favorable residue behavior. The individual phases in the composition are stable in storage for long periods, i.e. for example do not form any deposits, and the conversion into a temporary emulsion remains reversible, even after frequent shaking. In addition, the separation of ingredients into separate phases can promote the chemical stability of the composition.
A particular advantage of the invention lies in the high transparency of the continuous phases I and II and in the substantially or even 5 completely clouding-free boundary layer between them.
The compositions according to the invention contain citric acid and/or at least one citrate in a quantity of normally 0.1 to 30% by weight, preferably 1 to 20% by weight, more preferably 2 to 15% by weight and most preferably 4 to 12% by weight. The quantity to be selected for a certain concentration of citrate ions depends upon the nature of the cations in the form used which may be, on the one hand, the light protons of the acidic carboxyl groups and/or, on the other hand, heavier metallic cations or optionally alkylated ammonium ions.
Citric acid may be used, for example, in the form of its monohydrate citric acid ~ 1 H20.
In the context of the present invention, the citrates are the salts of 3x-deprotonated citric acid, unless otherwise specifically stated. However, the mono- and dihydrogen citrates may also be used in accordance with the invention.
One group of suitable citrates are, for example, the alkali metal, alkaline earth metal, ammonium and mono-, di- and trialkanolammonium citrates, preferably mono-, di- and triethanolammonium citrates, and mixtures thereof. Sodium citrate and potassium citrate are particularly suitable.
Potassium citrate or the use of citric acid in combination with potassium hydroxide has a particularly positive effect on phase separation, on the clearness of the phases and on the sharpness of and the substantial or complete absence of clouding from the phase boundary layer.
Accordingly, a preferred composition according to the invention in its first embodiment contains potassium citrate and/or citric acid in combina-tion with potassium hydroxide.

Accordingly, in a preferred use according to the invention in its fourth embodiment, potassium citrate and/or citric acid in combination with potassium hydroxide is used.
Accordingly, in a preferred process according to the invention in its fifth embodiment, potassium citrate and/or citric acid in combination with potassium hydroxide is used.
In the most simple case, a composition according to the invention comprises a lower continuous phase consisting of the entire phase I and an upper continuous phase consisting of the entire phase II. However, one or more continuous phases of a composition according to the invention may also contain parts of another phase in emulsified form, so that in a composition such as this part of phase I for example is present as continuous phase I, which represents the lower continuous phase of the composition, while another part is emulsified as discontinuous phase I in the upper continuous phase II. The same applies to phase II and other continuous phases.
In one preferred embodiment of the invention, the continuous phases I and II are demarcated from one another by a sharp interface.
In another preferred embodiment of the invention, one or both of the continuous phases I and II contain parts, preferably 0.1 to 25% by volume and more preferably 0.2 to 15% by volume, based on the volume of the particular continuous phase, of the other phase as dispersant. Accordingly, the continuous phase I or II is reduced by that part by volume which is distributed as dispersant in the other phase. Particularly preferred compositions are characterized in that phase I is emulsified in phase II in quantities of 0.1 to 25% by volume and preferably in quantities of 0.2 to 15% by volume, based on the volume of phase II.
Another preferred embodiment of the invention is characterized in that, besides the continuous phases I and I I, part of the two phases is present as an emulsion of one of the two phases in the other phase, this emulsion being demarcated by two sharp interfaces, namely an upper interface and a lower interface, from the other parts of phases I and II
which are not involved in the emulsion.
The compositions according to the invention contain phase I and phase II in a ratio volume of 90:10 to 10:90, preferably 75:25 to 25:75 and more preferably 65:35 to 35:65.
In one particularly advantageous embodiment of the invention, the compositions contain one or more hydrophobic components. Suitable hydrophobic components are, for example, dialkyl ethers with the same or different C4_~4 alkyl chains, more particularly dioctyl ethers; hydrocarbons with a boiling range of 100 to 300°C, more particularly 140 to 280°C, for example aliphatic hydrocarbons with a boiling range of 145 to 200°C, isoparaffins with a boiling range of 200 to 260°C; essential oils, more particularly limonene and pine oil extracted from pine roots and stubs; and also mixtures of these hydrophobic components, more particularly mixtures of two or three of the hydrophobic components mentioned. Preferred mixtures of hydrophobic components are mixtures of different dialkyl ethers, mixtures of dialkyl ethers and hydrocarbons, mixtures of dialkyl ethers and essential oils, mixtures of hydrocarbons and essential oils, mixtures of dialkyl ethers and hydrocarbons and essential oils and mixtures of these mixtures. The compositions contain hydrophobic components in quantities, based on the composition, of 0 to 20% by weight, preferably 0.1 to 14% by weight, more preferably 0.5 to 10% by weight and most preferably 0.8 to 7% by weight.
Besides citric acid and/or citrate, the compositions according to the invention may contain one or more other phase separation auxiliaries.
Suitable other phase separation auxiliaries are, for example, the alkali metal and alkaline earth metal halides, more particularly chlorides, and sulfates and also nitrates, more particularly sodium and potassium chloride and sulfate, and ammonium chloride and sulfate or mixtures thereof, sodium chloride being particularly preferred. Salts such as these as strong electrolytes support phase separation through the salt effect. The compositions contain phase separation auxiliaries in quantities, based on the composition, of 0 to 30% by weight, preferably 1 to 20% by weight, more preferably 3 to 15% by weight and most preferably 5 to 12% by weight. These phase separation auxiliaries are used in particular when the ionic strength produced by the other ionic compounds present does not produce the required phase separation.
The compositions according to the invention may contain anionic, nonionic, amphoteric or cationic surfactants or surfactant mixtures of one, several or all of these classes of surfactants as their surfactant component.
The compositions contain surfactants in quantities, based on the composition, of 0.01 to 30% by weight, preferably 0.1 to 20% by weight, more preferably 1 to 14% by weight and most preferably 3 to 10% by weight.
Suitable nonionic surfactants are, for example, C8_~8 alkyl alcohol polyglycol ethers, alkyl polyglycosides and nitrogen-containing surfactants or even sulfosuccinic acid di-C~_~2-alkyl esters or mixtures thereof, particularly mixtures of the first two. The compositions contain nonionic surfactants in quantities, based on the composition, of 0 to 30% by weight, preferably 0.1 to 20% by weight, more preferably 0.5 to 14% by weight and most preferably 1 to 10% by weight.
C8_~$ alkyl alcohol polypropylene glycol/polyethylene glycol ethers represent preferred known nonionic surfactants. They may be described by formula II:
R'O-(CH2CH(CH3)O)p(CH2CH20)e-H (II) in which R' is a linear or branched aliphatic alkyl and/or alkenyl group containing 8 to 18 carbon atoms, p is 0 or a number of 1 to 3 and a is a number of 1 to 20.
The Ca_~$ alkyl alcohol polyglycol ethers corresponding to formula II
may be obtained by addition of propylene oxide and/or ethylene oxide onto alkyl alcohols, preferably fatty alcohols. Typical examples are polyglycol ethers corresponding to formula II, in which R' is an alkyl group containing 8 to 18 carbon atoms, p is 0 to 2 and a is a number of 2 to 7. Preferred representatives are, for example, C~0.~4 fatty alcohol+1 PO+6E0 ether (p =
1, a = 6) and C~2_~$-fatty alcohol+7E0 ether (p = 0, a = 7) and mixtures thereof.
End-capped C$_~8 alkyl alcohol polyglycol ethers, i.e. compounds in which the free OH group in formula II is etherified, may also be used. The end-capped C8_~8 alkyl alcohol polyglycol ethers may be obtained by relevant methods of preparative organic chemistry. C8_~$ alkyl alcohol polyglycol ethers are preferably reacted with alkyl halides, more particularly butyl or benzyl chloride, in the presence of bases. Typical examples are mixed ethers corresponding to formula II, in which R' is a technical fatty alcohol moiety, preferably a C~2,~4 cocoalkyl moiety, p is 0 and a is a number of 5 to 10, which are end-capped with a butyl group.
Other preferred nonionic surfactants are alkyl polyglycosides (APGs) corresponding to formula III:
R20[G]x (II I) in which RZ is a linear or branched, saturated or unsaturated alkyl group containing 8 to 22 carbon atoms, [GJ is a glycosidic sugar unit and x is a number of 1 to 10. APGs are nonionic surfactants and represent known substances which may be obtained by the relevant methods or preparative organic chemistry. The index x in general formula III indicates the degree of oligomerization (DP degree), i.e. the distribution of mono- and oligoglycosides, and is a number of 1 to 10. Whereas x in a given compound must always be an integer and, above all, may assume a value of 1 to 6, the value x for a certain alkyl glycoside is an analytically determined calculated quantity which is generally a broken number. Alkyl glycosides with an average degree of oligomerization x of 1.1 to 3.0 are preferably used. Alkyl glycosides with a degree of oligomerization of less than 1.7 and, more particularly, between 1.2 and 1.6 are preferred from the applicational point of view. Xylose, but especially glucose is preferably used as the glycidic sugar.
5 The alkyl or alkenyl group R2 in formula III may be derived from primary alcohols containing 8 to 18 and preferably 8 to 14 carbon atoms.
Typical examples are caproic alcohol, caprylic acid, capric alcohol and undecyl alcohol and the technical mixtures thereof obtained, for example, in the hydrogenation of technical fatty acid methyl esters or in the 10 hydrogenation of aldehydes from ROELEN's oxosynthesis.
However, the alkyl or alkenyl group R2 is preferably derived from lauryl alcohol, myristyl alcohol, cetyl alcohol, palmitoleyl alcohol, stearyl alcohol, isostearyl alcohol or oleyl alcohol. Elaidyl alcohol, petroselinyl alcohol, arachidyl alcohol, gadoleyl alcohol, behenyl alcohol, erucyl alcohol and technical mixtures thereof may also be mentioned.
Other suitable nonionic surfactants are nitrogen-containing surfactants, for example fatty acid polyhydroxyamides, for example glucamides, and ethoxylates of alkyl amines, vicinal diols and/or carboxylic acid amides which contain C~o_22 and preferably C~2_~s alkyl groups. The degree of ethoxylation of these compounds is generally between 1 and 20 and preferably between 3 and 10. Ethanolamide derivatives of C8_22 and preferably C~2_~6 alkanoic acids are preferred. Particularly suitable compounds include lauric acid, myristic acid and palmitic acid monoethanolamides.
Suitable anionic surfactants are the preferred C8_~s alkyl sulfates, C$_~$ alkyl ether sulfates, i.e. the sulfation products of alcohol ethers corre-sponding to formula II, and/or C8_~s alkyl benzenesulfonates, more particu-larly dodecyl benzenesulfonate, but also Ca_~8 alkane sulfonates, C8_~8 a-olefin sulfonates, sulfonated C8_~8 fatty acids, C$_22 carboxylic acid amide ether sulfates, sulfosuccinic acid mono-C~_~2-alkyl esters, Ca_~8 alkyl poly-glycol ether carboxylates, C$_~8 N-acyl taurides, C8_~$ N-sarcosinates and C8_~s alkyl isethionates and mixtures thereof. They are used in the form of their alkali metal and alkaline earth metal salts, more particularly sodium, potassium and magnesium salts, and ammonium salts and mono-, di-, tri-and tetraalkyl ammonium salts and - in the case of the sulfonates also in the form of their corresponding acid, for example dodecyl benzenesulfonic acid. Where sulfonic acid is used, it is normally neutralized to the above-mentioned salts in situ with one or more corresponding bases, for example alkali metal and alkaline earth metal hydroxides, more particularly sodium, potassium and magnesium hydroxide, and ammonia or mono-, di-, tri- or tetraalkyl amine. The compositions contain anionic surfactants in quanti-ties, based on the composition, of 0 to 30% by weight, preferably 0.1 to 20% by weight, more preferably 1 to 14% by weight and most preferably 2 to 10% by weight.
Where the particularly preferred alkyl benzenesulfonic acids are used, clouding can occur in the vicinity of the boundary layer between phases I and II, particularly if the sodium chloride content is high and/or sodium hydroxide is used for neutralization. According to the invention, this problem is countered by citric acid or citrate alone. However, a further improvement is obtained where the alkyl benzenesulfonic acid is neutralized with potassium hydroxide which has a particularly positive effect on phase separation, on the clearness of the phases and on the sharpness of and substantial or complete absence of clouding from the phase boundary layer.
By virtue of their foam-suppressing properties, soaps, i.e. alkali metal or ammonium salts of saturated or unsaturated Cs_22 fatty acids, may also be present in the compositions according to the invention. The soaps may be used in a quantity of up to 5% by weight and are preferably used in a quantity of 0.1 to 2% by weight.
Suitable amphoteric surfactants are, for example, betaines corresponding to the formula (R3)(R4)(R5)N+CH2C00), in which R3 is a C8_ 25 and preferably C~o_2~ alkyl group optionally interrupted by hetero atoms or groups of hetero atoms and R4 and R5 may be the same or different and represent C~_3 alkyl groups, more particularly C~o_~8 alkyl dimethyl carboxymethyl betaine and C»_~~ alkylamidopropyl dimethyl carboxymethyl betaine. The compositions contain amphoteric surfactants in quantities, based on the composition, of 0 to 15% by weight, preferably 0.01 to 10%
by weight and more preferably 0.1 to 5% by weight.
Suitable cationic surfactants are inter alia quaternary ammonium compounds corresponding to the formula (R6)(R~)(R$)(R9)N+X), in which R6 to R9 represent four identical or different alkyl groups, more particularly two long-chain and two short-chain alkyl groups, and X) is an anion, more particularly a halide ion, for example didecyl dimethyl ammonium chloride, alkyl benzyl didecyl ammonium chloride and mixtures thereof. The compo-sitions contain cationic surfactants in quantities, based on the composition, of 0 to 10% by weight, preferably 0.01 to 5% by weight and more preferably 0.1 to 3% by weight.
In one preferred embodiment, the compositions according to the invention contain anionic and nonionic surfactants alongside one another, preferably C8_~$ alkyl benzenesulfonates, C$_~8 alkyl sulfates and/or C8_~a alkyl ether sulfates alongside C8_~$ alkyl alcohol polyglycol ethers and/or alkyl polyglycosides, more particularly C8_~e alkyl benzenesulfonates alongside C8_~$ alkyl alcohol polyglycol ethers.
Besides the citric acid and/or citrate, the compositions according to the invention may additionally contain one or more other builders. Suitable builders are, for example, alkali metal gluconates, nitrilotriacetates, carbonates and bicarbonates, more particularly sodium gluconate and nitrilotriacetate and sodium and potassium carbonate and bicarbonate, and also alkali metal and alkaline earth metal hydroxides, more particularly sodium and potassium hydroxide, ammonia and amines, more particularly mono- and triethanolamine, and mixtures thereof. These builders also include the salts of glutaric acid, succinic acid, adipic acid, tartaric acid and benzenehexacarboxylic acid and also phosphonates and phosphates, for example the pentasodium triphosphate better known as sodium tripoly-phosphate or sodium hexametaphosphate, such as for example a mixture of condensed orthophosphates corresponding to formula I, in which n has an average value of about 12. The compositions contain builders in quantities, based on the composition, of 0 to 20% by weight, preferably 0.01 to 12% by weight, more preferably 0.1 to 8% by weight and most preferably 0.3 to 5% by weight. The builders additionally act as phase separation aids.
A particularly preferred builder is potassium hydroxide because it has a particularly positive effect on phase separation, on the clearness and color brightness of the phases and on the sharpness of and substantial or complete absence of clouding from the phase boundary layer.
Besides the components mentioned, the compositions according to the invention may contain other auxiliaries and additives typically present in such compositions. These include, in particular, polymers, soil release agents, solvents (for example ethanol, isopropanol, glycol ether), solubilizers, hydrotropes (for example cumene sulfonate, octyl sulfate, butyl glucoside, butyl glycol), cleaning boosters, viscosity regulators (for example synthetic polymers, such as polysaccharides, polyacrylates, naturally occurring polymers and derivatives thereof, such as xanthan gum, other polysaccharides and/or gelatin), disinfectants, antistatic agents, preservatives, bleaching systems, enzymes, perfume, dyes and fragrances and also opacifiers and even the skin-care agents described in EP-A-533 556. Additives such as these are normally present in the cleaning composition in quantities of not more than 12% by weight. The lower limit to the quantity used is determined by the nature of the additive and, in the case of dyes for example, may be 0.001 % by weight or lower. The quantity of auxiliaries used is preferably between 0.01 and 7% by weight and more preferably between 0.1 and 4% by weight.
In one preferred embodiment of the invention, the compositions contain one or more perfumes in a quantity of 0.1 to 5% by weight, preferably in a quantity of 0.2 to 3% by weight, more preferably in a quantity of 0.5 to 2% by weight and most preferably in a quantity of 1 to 1.5% by weight. If a hydrophobic component is simultaneously present, the perfumes and the hydrophobic component are predominantly present in the same phase - generally the upper phase II. This has the advantageous effect of intensifying the fragrance released from the top of a container holding such a composition according to the invention after it has been opened. Through their essential oils, perfumes also influence the phase separation properties of the compositions according to the invention, the ratio of phase I to phase II generally shifting in favor of phase I with increasing perfume content.
The pH value of the compositions according to the invention can be varied over a wide range, although a range of 2.5 to 12 is preferred and a range of 5 to 10.5 particularly preferred. In the context of the invention, the pH value of the compositions according to the invention is understood to be the pH value of the composition in the form of the temporary emulsion.
In one preferred embodiment of the invention, the compositions are adjusted to an alkaline pH value of 8 to 12, preferably 8.5 to 11.5, more preferably 9 to 11 and most preferably 9.3 to 10.5.
Suitable pH regulators are, on the one hand, mineral acids, for example hydrochloric acid, but especially citric acid, and on the other hand the alkaline builders mentioned above, preferably sodium hydroxide but especially potassium hydroxide by virtue of the advantages mentioned above.
To stabilize or buffer the pH value, the composition according to the invention - in one particular embodiment - contains small quantities of corresponding buffers, for example soda in the described alkaline embodiment.
The compositions according to the invention may be produced by mixing directly from their raw materials, subsequent intermixing and, in a final step, allowing the composition to stand for separation of the temporary emulsion.
The composition according to the invention is sprayable and, accordingly, may be used in a spray dispenser.
Accordingly, the present invention also relates to a product 5 containing a composition according to the invention and a spray dispenser.
The spray dispenser is preferably a hand-operated spray dispenser, more particularly selected from the group consisting of aerosol spray dispensers, self-pressure-generating spray dispensers, pump spray dispensers and trigger spray dispensers, more especially pump spray 10 dispensers and trigger spray dispensers comprising a container of transparent polyethylene or polyethylene terephthalate. Spray dispensers are described in more detail in WO 96104940 (Procter & Gamble) and the US patents cited therein on the subject of spray dispensers, to which reference is made in this regard and of which the disclosures are hereby 15 incorporated in the present application.
The compositions according to the invention are used, for example, by applying the composition temporarily converted into an emulsion by shaking to the surface to be cleaned in quantities of about 1.5 to 10 g per m2 and more particularly in quantities of 3 to 7 g per mz and wiping the surface immediately afterwards with a soft absorbent material and thus cleaning it. The compositions are applied, for example, by suitable spray applicators, more particularly a spray dispenser or a product according to the invention, in order to achieve uniform distribution. Sponges or cloths in particular may be used for wiping and may be periodically rinsed out with water in the cleaning of relatively large surfaces.
Examples Example 1 Compositions E1 to E6 according to the invention and comparison composition C1 were produced as described above. Table 1 below shows their compositions in % by weight, their pH value and for E1 to E6 the quantified ratio by volume of the lower phase I to the upper phase II. In C1, too, the lower phase I made up slightly more than half the total volume.
Compositions E1 to E6 and C1 additionally contain 0.05% by weight of glutaraldehyde as preservative and, except for C5, small quantities of dye which, in the other compositions, colored the lower phase turquoise and the upper phase blue.
Table 1 Composition [% by weight E1 E2 E3 E4 E5 E6 C1 Dodecyl benzenesulfonic 4 4 4 4 3 4 4 acid C,o_,4 fatty alcohol+1 PO+1 EO

ether - - - - 2 - -C,2_,sfatty alcohol+7E02 2 2 2 - 2 2 ether C,Z_,4 fatty alcohol+9E0 butyl ether - - - - 2 - -C8_,o alkyl-1,5-glucoside - - - - 4 - -Citric acid 1 H20 6 6.2 6 6.5 8 6.2 -Sodium chloride - - - - - - 6.9 Potassium hydroxide 5.5 5.6 5.5 5.78 - - -Sodium hydroxide - - - - 4.7 5.6 0.5 Dioctyl ether 5 5 5 5 5 5 5 Perfume 0.9 0.9 0.9 0.9 0.9 0.9 0.5 Water to to to to to to 100 100 100 100 100 100to pH value 9.5 9.5 9.5 9.5 9 9.5 10.15 Ratio by volume of phase I to phase II 60:4060:4070:3060:40 70:3060:40-Accordingly, all compositions showed two continuous phases which temporarily formed a creamy looking emulsion on shaking. However, whereas the upper phase II in C1 was slightly milky and showed signs of clouding in the vicinity of the phase boundary, particularly after repeated shaking, the compositions according to the invention contained transparent phases with a clouding-free, sharp phase boundary and brighter colors, even after repeated shaking.
Example 2 - Cleaning performance The cleaning performance of compositions E1 and C2 to C6, which were produced as described above from the ingredients listed in Table 2, were tested both in diluted and in undiluted form.
Unless otherwise stated in the following, cleaning performance was tested in accordance with the Qualifatsnormen fur Fuf3bodenpflege- and -reinigungsmittel des Industrieverbandes Putz- and Pflegemiftel e. V. (IPP), Frankfurt/M (Seifen - Ule - Fette - Wachse 1986, 112, 371-372). The test was carried out with quantities of 10 ml of dilute test substance with a concentration of 1.5 and 6 ml/I and soil 2 and with quantities of 6 ml of undiluted test substance and a soil of oil, fat, white spirit and a soot/pigment mixture.
The test is carried out by wiping a white soil carrier treated with test soil with a sponge impregnated with the product to be tested under defined conditions and measuring the cleaning effect photoelectrically against the untreated white soil carrier.
A machine similar to an Erichsen 494 washability and scouring tester (Erichsen GmbH, D-58675 Hemer-Sundwig) with a guide rail of brass and an 820 g weight was used for wiping.
Whiteness was measured with a Dr. Lange Micro-Color color difference measuring instrument (Dr. Lange, D-40549 DusseldorfJ and is expressed as the average of 21 measurements per test strip.
Cleaning performance was measured in a triple determination and is shown in Table 2 as the relative cleaning performance CPre~ in % for the two diluted products and the undiluted product.

Table 2 Composition [% by weight] E7 C2 C3 C4 C5 C6 Dodecyl benzenesulfonic 6 6 6 6 6 6 acid .

C~2_~$ fatty alcohol+7E0 4 4 4 4 4 4 ether Sodium hydroxide 0.78 0.78 0.78 0.78 0.78 0.78 C~2_~4 fatty alcohol +2E0 ether sulfate sodium salt 3 3 3 3 3 3 C~2_~$ cocofatty acid 1 1 1 1 1 1 Trisodium citrate 3 - - - - -Sodium gluconate - - 3 - - -Sodium tripolyphosphate - - - 3 - 3 Urea - - - - 5 5 Water to to to to to to Cleaning performance CP~e, diluted (1.5 ml/I) [%] 90 74 86 88 76 90 CPre, diluted (6 ml/I) [%] 102 100 98 102 09 102 CP~e, undiluted [%] 172 100 131 147 103 138 Composition E7 according to the invention not only had a consistently better cleaning performance than the builder-free comparison composition C1, it was also at least equivalent and generally even superior in its cleaning performance to the other builder-containing comparison compositions C1 to C6, this superiority being reflected in particular in the results achieved with the undiluted compositions against obstinate soils.

Claims (25)

1. A water-based, liquid, multiphase, surfactant-containing cleaning composition with at least two continuous phases which contains at least one lower aqueous phase I and an upper aqueous phase II immiscible therewith and which can be temporarily converted into an emulsion by shaking, characterized in that it contains citric acid and/or at least one citrate.

2. A composition as claimed in claim 1, characterized in that it contains citric acid and/or at least one citrate in a quantity of 0.1 to 30% by weight, preferably 1 to 20% by weight, more preferably 2 to 15% by weight and most preferably 4 to 12% by weight.

3. A composition as claimed in claim 1 or 2, characterized in that it contains citrate from the group of alkali metal, alkaline earth metal, ammonium and mono-, di- and trialkanolammonium citrates, preferably mono-, di- and triethanolammonium citrates, or mixtures thereof, more particularly sodium citrate and most preferably potassium citrate.

4. A composition as claimed in any of claims 1 to 3, characterized in that the continuous phases I and II are demarcated from one another by a sharp interface.

5. A composition as claimed in any of the preceding claims, characterized in that one or both of the continuous phases I and II contain parts, preferably 0.1 to 25% by volume and more preferably 0.2 to 15% by volume, based on the volume of the particular continuous phase, of the other phase as dispersant.

6. A composition as claimed in any of the preceding claims, characterized in that phase I is emulsified into phase II in quantities of 0.1 to 25% by volume and preferably in quantities of 0.2 to 15% by volume, based on the volume of phase II.

7. A composition as claimed in any of the preceding claims, characterized in that besides the continuous phases I and II, part of the two phases is present as an emulsion of one of the two phases in the other phase, this emulsion being demarcated by two sharp interfaces, namely an upper and a lower interface, from those parts of phases I and II which are not involved in the emulsion.

8. A composition as claimed in any of the preceding claims, characterized in that it contains phase I and phase II in a ratio by volume of 90:10 to 10:90, preferably 75:25 to 25:75 and more preferably 65:35 to 35:65.

9. A composition as claimed in any of the preceding claims, characterized in that it additionally contains hydrophobic components from the group of dialkyl ethers containing identical or different C4-14 alkyl chains, more particularly dioctyl ethers, hydrocarbons with a boiling range of 100 to 300°C and more particularly 140 to 280°C, essential oils, more particularly limonene and pine oil, and mixtures thereof, more particularly mixtures of two or three of the hydrophobic components mentioned.

10. A composition as claimed in any of the preceding claims, characterized in that it contains additional phase separation auxiliary, preferably from the group of alkali metal and alkaline earth metal chlorides and sulfates, more particularly sodium and potassium chloride and sulfate, and ammonium chloride and sulfate or mixtures thereof.

11. A composition as claimed in any of the preceding claims, characterized in that it contains anionic surfactant, preferably from the group of C8-18 alkyl sulfates, C8-18 alkyl ether sulfates and C8-18 alkyl benzenesulfonates and mixtures thereof.

12. A composition as claimed in the preceding claim, characterized in that it contains at least one anionic surfactant in the form of its potassium salt.

13. A composition as claimed in any of the preceding claims, characterized in that it contains nonionic surfactant, preferably from the group of C8-18 alkyl alcohol polyglycol ethers, alkyl polyglycosides and mixtures thereof.

14. A composition as claimed in any of the preceding claims, characterized in that it contains anionic and nonionic surfactant, preferably C8-18 alkyl benzenesulfonates, C8-18 alkyl sulfates and/or C8-18 alkyl ether sulfates, alongside C8-16 alkyl alcohol polyglycol ethers and/or alkyl poly-glycosides, more particularly C8-18 alkyl benzenesulfonates alongside C8-alkyl alcohol polyglycol ethers.

15. A composition as claimed in any of the preceding claims, characterized in that it contains one or more cationic surfactants.

16. A composition as claimed in any of the preceding claims, characterized in that it contains additional builders, preferably from the group of alkali metal gluconates, nitrilotriacetates, carbonates and bicarbonates and alkali metal and alkaline earth metal hydroxides, ammonia and amines, more particularly mono- and triethanolamine, or mixtures thereof.

17. A composition as claimed in the preceding claim, characterized in that it contains potassium hydroxide as an additional builder.

18. A composition as claimed in any of the preceding claims, characterized in that it contains one or more perfumes in a quantity of 0.1 to 5% by weight, preferably 0.2 to 3% by weight, more preferably 0.5 to 2%
by weight and most preferably 1 to 1.5% by weight.

19. A process for the production of the composition claimed in any of the preceding claims by mixing directly from its raw materials, subsequent intermixing and, in a final step, allowing the composition to stand for separation of the temporary emulsion.

20. The use of a water-based, liquid, multiphase, surfactant-containing cleaning composition with at least two continuous phases which contains at least one lower aqueous phase I and an upper aqueous phase II
immiscible therewith, which can be temporarily converted into an emulsion by shaking and which contains citric acid and/or at least one citrate for cleaning hard surfaces.

21. The use of citric acid and/or at least one citrate in a water-based, liquid, multiphase, surfactant-containing cleaning composition with at least

22 two continuous phases, which contains at least one lower aqueous phase I
and an upper aqueous phase II immiscible therewith and which can be temporarily converted into an emulsion by shaking, as a phase separation auxiliary and/or for reducing clouding in the vicinity of the boundary layer between phases I and II.
22. The use claimed in the preceding claim, characterized in that potassium citrate and/or citric acid in combination with potassium hydroxide is used.

23. A process for the production of a water-based, liquid, multiphase, surfactant-containing cleaning composition with at least two continuous phases, which contains at least one lower aqueous phase I and an upper aqueous phase II immiscible therewith and which can be temporarily converted into an emulsion by shaking, characterized in that citric acid and/or at least one citrate is used an auxiliary for separating the phases and/or for reducing clouding in the vicinity of the boundary layer between phases I and II.

24. A process as claimed in the preceding claim, characterized in that potassium citrate and/or citric acid in combination with potassium hydroxide is used.

25. A product containing the composition claimed in any of the preceding composition claims and a spray dispenser.