GB2401110A - Liquid hard surface cleaning agent - Google Patents

Abstract

Compositions which form at least two separate liquid phases when left in a quiescent state, which may be physically shaken to reconstitute the at least two separate phases, which compositions which are useful in providing a cleaning and/or disinfecting treatment of hard surfaces. Methods for the manufacture of such compositions, and methods for their use particularly in the treatment of hard surfaces in order to provide a cleaning effect are also disclosed.

Description

IMPROVEMENTS IN OR RELATED TO ORGANIC COMPOSITIONS

The present invention relates to compositions which are useful in providing a cleaning and/or disinfecting treatment of hard surfaces. More particularly the present invention relates to compositions which form at least two separate liquid phases when left in a quiescent state, which may be physically shaken to reconstitute the at least two separate phases, which compositions which are useful in providing a cleaning and/or disinfecting treatment of hard surfaces.

A recurring problem is that when cleaning hard surfaces, such as may be found in the kitchen or bathroom area, or win the cleaning of soft surfaces, such as textiles, as well as soiled garments and fabrics, is that both inorganic and organic stains and soils need to be treated and removed. Whereas surfactants and soaps are usually effective in removing organic stains and soils from such surfaces, they are usually less effective, or ineffective, in removing inorganic stains and soils. In order to remove inorganic stains and soils, including for example limescale, it is therefore necessary to use compounds, often in aqueous solution, which are suitable for dissolving or detaching this dirt. Depending on the nature of the dirt, these might be acid, neutral or alkaline compounds. In order to detach deposits of limescale, the buildup upon hard surfaces which is usually attributable to hardness-forming elements in water, it is preferred to use acid containing aqueous solutions. In order to remove other types of organic stains and soils, for example stains and soils containing clay and/or pigment, it is preferable to use aqueous solutions of ingredients which produce a pH value in the neutral or alkaline range in aqueous solution.

In both cases, however, it has been found that the addition of surfaceactive agents to aqueous solutions used for removing inorganic stains and soils (if they are also required to remove organic stains and soils) can lead to a significant reduction in their effectiveness against inorganic stains and soils. Thus, providing an aqueous based composition effective against both inorganic stains and soils is not a trivial technical matter.

One solution to the above identified problem has been proposed in US Published Patent Application US2002/0077268A1 to Benckiser N.V. which discloses aqueous multi-phase compositions which in a quiescent state, exist separately as two separate aqueous phases. When the compositions are intended to be used, these compositions are physically shaken in order to intermix the phases present in the compositions, afterwards the mixed composition may be applied to the locus of a stain or soil on a surface to be S treated, such as a hard surface. While effective in many regards, these compositions appear to be necessarily formed from two different premixtures, which are not to be intermixed to form the final composition until these premixtures are provided to the final i bottle or container in which the product will be shipped, or are intermixed immediately before introduction into the final bottle or container. These compositions also suffer a the further shortcoming in that the viscosity of these compositions particularly when shaken to form a mixture of the two aqueous phases present is somewhat ineffective in the treatment of certain surfaces particularly inclined hard surfaces such as may be present on walls, inclined surfaces present in lavatory fixtures, e.g., toilet bowls, bidets, as well as on soft surfaces, such as textiles and fabrics where it is desired to provide controlled dispensing of the composition without spreading undesirably throughout the textile or fabric, e.g. spot cleaning or spot pretreatment.

Another dual-layer composition known to the art is that disclosed in PCT/EP99/0795 1. While effective the compositions therein are of very low viscosity I which limits the range of substrates which may be effectively treated using such compositions.

The compositions of the present invention overcome many of the problems attendant upon prior art compositions, and are addressed to compositions with improved viscosity characteristics. This and other objects of the invention will become evident

from the following specification.

According to one aspect of the invention there is provided a liquid hard surface cleaning composition which includes at least a first aqueous phase and at least a second separate aqueous phase, wherein the liquid hard surface cleaning composition, when well shaken or well stirred, exhibits a viscosity of at least 25 cps, more preferably is at least SO i cps, but most preferably does not exceed about 200 cps, preferably does not exceed about 150 cps as measured using a Brookfield viscometer using spindle 2, at 60 rpm, operating at room temperature. The composition may be formed from a single mixture, which premixture may be maintained in a well mixed state during its manufacture, but which, when permitted to rest without agitation, separated into at least two visibly distinct aqueous layers.

A further aspect of the invention are directed to a process for manufacturing a liquid hard surface cleaning composition which includes at least a first aqueous phase and at least a second separate aqueous phase as described herein, which process contemplates the steps of: forming the composition in a single mixing vessel, and thereafter permitting the composition to separate into at least two visibly distinct aqueous layers.

The division of the constituents of the composition between the aqueous preliminary mixtures will naturally depend to a large degree on what constituents are incorporated in the overall composition itself. Since it is not always possible to establish clearly in every case which constituent or combinations of constituent are responsible for causing the desired phase separation of the overall composition, it will be necessary to determine the composition of the preliminary mixture in each individual case through appropriate tests, and these can be easily conducted by the person skilled in the art on the basis of the known effect of the individual constituent in the overall composition and their limited number, particularly without any personal inventive activity. Desirably however, the constituents are selected such that when the composition is at rest, viz. in a quiescent state, it separates into two aqueous phases, an upper phase and a lower phase wherein the respective volume ratios of the said upper to lower phases is in the ranges of 40 /O - 60%: 60% - 40%, although most desirably the an upper phase and a lower phase are present in approximately equal volume ratios, viz., 50%:50%.

The multi-phase liquid hard surface cleaning compositions according to the invention necessarily contain at least two germicidal constituents a first cationic surfactant, a second cationic surfactant which comprises a fatty alkyl group derived from a naturally occurring source. Any cationic surfactants which satisfy these definitions may be used and are considered to be within the scope of the present invention, and mixtures of two or more cationic surface active agents, viz., cationic surfactants, may also be used for each of the first and second cationic surfactants. Cationic surfactants are, per se, well known, and useful cationic surfactants may be one or more of those described for example in McCutcheon's Functional Materials, Vol.2, 1998; Kirk-Othmer, - 3 Encyclopedia of Chemical Technology, 4th Ed., Vol. 23, pp. 481-541 (1997), the contents of which are herein incorporated by reference. These are also described in the respective product specifications arid literature available from the suppliers of these cationic surfactants.

Examples of preferred first cationic surfactants in the practice of the instant invention are those which provide a germicidal effect to the compositions, and especially preferred are quaternary ammonium compounds and salts thereof, which may be characterized by the general structural formula: IR' R2-I-R3 X R4 where at least one of Rat, R2, R3 and R4 is a alkyl, aryl or alkylaryl substituent of from 6 to 26 carbon atoms, and the entire cation portion of the molecule has a molecular weight of at least 165. The alkyl substituents may be long- chain alkyl, long-chain alkoxyaryl, long chain alkylaryl, halogen- substituted long-chain alkylaryl, long-chain alkylphenoxyalkyl, arylalkyl, etc. The remaining substituents on the nitrogen atoms other than the abovementioned alkyl substituents are hydrocarbons usually containing no more than 12 carbon atoms. The substituents Rat, R2, R3 and R4 may be straight-chained or may be branched, but are preferably straight-chained, and may include one or more amide, ether or ester linkages. The counterion X may be any salt-forming anion which permits water solubility of the quaternary ammonium complex.

Exemplary quaternary ammonium salts within the above description include the alkyl ammonium halides such as cetyl trimethyl ammonium bromide, alkyl aryl ammonium halides such as octadecyl dimethyl benzyl ammonium bromide, N-alkyl pyridinium halides such as N-cetyl pyridinium bromide, and the like. Other suitable types of quaternary ammonium salts include those in which the molecule contains either amide, ether or ester linkages such as octyl phenoxy ethoxy ethyl dimethyl benzyl ammonium chloride, N-(laurylcocoaminoformylmethyl)-pyridinium chloride, and the like. Other very effective types of quaternary ammonium compounds which are useful as germicides include those in which the hydrophobic radical is characterized by a substituted aromatic nucleus as in the case of lauryloxyphenyltrimethyl ammonium chloride, cetylaminophenyltrimethyl ammonium methosulfate, dodecylphenyltrimethyl ammonium methosulfate, dodecylbenzyltrimethyl ammonium chloride, chlorinated dodecylbenzyltrimethyl ammonium chloride, and the like.

S Preferred quaternary ammonium compounds useful as the first cationic surfactants which are found useful in the practice of the present invention include those which have the structural formula: I H3 R2-I-R3 X CH3 wherein R2 and R3 are the same or different C'2-C'alkyl, or R2 is C'2 Alkyd, Cal alkylethoxy, Cat salkylphenolethoxy and R3 is benzyl, and X is a halide, for example chloride, bromide or iodide, or is a methosulfate anion. The alkyl groups recited in R2 and R3 may be straight-chained or branched, but are preferably substantially linear.

Particularly preferred for use as the first cationic surfactants are those according to the prior formula wherein R3 is methyl, and R2 is a substantially linear Cat Alkyd group, but especially is selected from C'6 and Cal alkyl groups.

Exemplary useful as the first cationic surfactants include materials available under the BARDAC, BARQUAT, HYAMINE, LONZABAC, and ONYXIDE trademarks, as well as from other sources, and which are more fully described in, for example, McCutcheon's Functional Materials (Vol. 2), North American Edition, 1998, as well as the respective product literature from the suppliers identified below. For example, BARDAC 205M is described to be a liquid containing alkyl dimethyl benzyl ammonium chloride, octyl decyl dimethyl ammonium chloride; didecyl dimethyl ammonium chloride, and dioctyl dimethyl ammonium chloride (50% active) (also available as 80% active (BARDAC 208M)); described generally in McCutcheon's as a combination of alkyl dimethyl benzyl ammonium chloride and dialkyl dimethyl ammonium chloride); BARDAC 2050 is described to be a combination of octyl decyl dimethyl ammonium chloride/didecyl dimethyl ammonium chloride, and dioctyl - 5 dimethyl ammonium chloride (50% active) (also available as 80% active (BARRACK 2080)); BARDAC 2250 is described to be didecyl dimethyl ammonium chloride (50% active); BARRACK LF (or BARRACK LF-80), described as being based on dioctyl dimethyl ammonium chloride (BARQUAT() MB-50, MX-50, OJ-50 (each 50% liquid) and MB-80 or MX-80 (each 80% liquid) are each described as an alkyl dimethyl benzyl ammonium chloride; BARRACK 4250 and BARQUAT 4250Z (each 50% active) or BARQUAT 4280 and BARQUAT 4280Z (each 80% active) are each described as alkyl dimethyl benzyl ammonium chloride/alkyl dimethyl ethyl benzyl ammonium chloride.

Also, HYAMINE 1622, described as diisobutyl phenoxy ethoxy ethyl dimethyl benzyl ammonium chloride (50% solution); HYAMINE 3500 (50% actives), described as alkyl dimethyl benzyl ammonium chloride (also available as 80% active (HYAMINE 3500-80)); and HYMAINE 2389 described as being based on methyldodecylbenzyl ammonium chloride and/or methyldodecylxylene-bistrimethyl ammonium chloride.

(BARRACK, BARQUAT and HYAMINE are presently commercially available from Lonza, Inc., Fairlawn, New Jersey). BECK 50 NF (or BECK 65 NF) is described to be alkyl dimethyl benzyl ammonium chloride (50% active); BECK 99 is described as didecyl dimethyl ammonium chloride (50% acive); BECK 776 is described to be myrisalkonium chloride (50% active); ETCH 818 is described as being octyl decyl dimethyl ammonium chloride, didecyl dimethyl ammonium chloride, and dioctyl dimethyl ammonium chloride (50% active) (available also as 80% active (ETCH 818 80%)); BECK 824 and BECK 835 are each described as being of alkyl dimethyl benzyl ammonium chloride (each 50% active); ETCH 885 is described as a combination of ETCH 835 and ETCH 818 (50% active) (available also as 80% active (BTCU3) 888)); ETCH 1010 is described as didecyl dimethyl ammonium chloride (50% active) (also available as 80% active (BECK 1010-80)); ETCH 2125 (or BECK 2125 M) is described as alkyl dimethyl benzyl ammonium chloride and alkyl dimethyl ethylbenzyl ammonium chloride (each 50% active) (also available as 80% active (ETCH 2125 80 or ETCH 2125 M)); BTC 2565 is described as alkyl dimethyl benzyl ammonium chlorides (50% active) (also available as 80% active (ETCH 2568)); ETCH 8248 (or BTC 8358) is described as alkyl dimethyl benzyl ammonium chloride (80% active) (also available as 90% active (BECK 8249)); ONYXIDE 3300 is described as n-alkyl dimethyl benzyl - 6 ammonium saccharinate (95% active). (ETCH and ONYXIDE are presently commercially available from Stepan Company, Northfield, Illinois.) Polymeric quaternary ammonium salts based on these monomeric structures are also considered desirable for the present invention. One example is POLYQUAT, described as being a 2-butenyldimethyl ammonium chloride polymer.

The first cationic surfactant(s) may be present in any effective amount, but generally need not be present in amounts in excess of about 1 0%wt. based on the total weight of the composition. The preferred cationic surfactants useful as the first cationic surfactant may be present in the multi-phase liquid compositions of the invention in amounts of from about 0.001 % by weight to up to about 10% by weight, very preferably are present in amounts of about 0.01-8% by weight, more preferably in amount of between 0.5-6 % by weight, and most preferably from 2 - 4% by weight.

The multi-phase liquid hard surface cleaning compositions according to the invention further necessarily contains a second cationic surfactant which comprises a fatty alkyl group derived from a naturally occurring source. Preferred quaternary ammonium compounds useful as the second cationic surfactants in the practice of the present invention include those which have the structural formula: ICH3 R2-I-R3 X CH3 wherein R2 is a lower alkyl group containing 1 to 4 carbon atoms, preferably is a methyl group and R3 is fatty alkyl group derived from a naturally occurring source. Naturally occurring sources for this fatty acid group include oils, and tallows of which tallows are most desirably the source of the fatty alkyl group. The fatty acid group may be fully saturated but likely contains one or more double bounds within the fatty acid group which however may become hydrogenated when provided to the water present in the inventive compositions. The fatty alkyl group contains a blend of several alkyl groups which may cover a broad spectrum, typically the fatty alkyl group contains 12 to 28, preferably 14 to 22, and especially a preponderance of 14 to 18 carbon atoms. Tallows typically comprise - 7 a blend materials, including lauryl, myristyl, palmyl, palmitoleyl, stearyl, oleyl, linoleyl, and arachidiyl. In the above formula, X is a halide, for example chloride, bromide or iodide, or is a methosulfate anion. While not clearly understood it is believed that the combination of the particularly preferred non-hydrogenated quaternary ammonium surfactant, namely the hexadecyltrimethylammonium chloride in conjunction with the quaternary ammonium surfactant containing the tallowalkyl substituent may provide a synergistic effect with regards to phase separation of the upper and lower aqueous layers in the inventive compositions. The present inventors have found that the separation of the upper layer and the lower layer of the compositions is largely dependent upon the amounts of the first cationic surfactant, and the second cationic surfactant which comprises a fatty alkyl group derived from a naturally occurring source and organic hydrotrope constituent present in the compositions. Good results have been obtained when the first cationic surfactant and the second cationic surfactant are present in weight ratios of about at least 2:1, preferably of about at least 2.8:1, and most preferably wherein, based on weights, at least about three times the amount of the first cationic surfactant is present with respect to the amount of the second cationic surfactant present.

Desirably the second cationic surfactant containing the fatty alkyl group derived from a naturally occurring source is present in amounts of at least about 0.1%wt. based on the total weight of the multi-phase liquid composition of the invention, preferably in amounts of 0.1 %wt., to 1 %wt. , and most preferably are present in amounts of 0.3%wt. to 0.7%wt. in the multi-phase liquid compositions according to the invention. Most preferably this second cationic surfactant is present in an amount of about 0.5%wt.

The inventive compositions includes at least one acid constituent which is present in an effective amount such that the overall pH of the inventive composition is less than about 1.5, and preferably is not in excess of 1.0, and in certain particularly preferred embodiments is not in excess of 0.8. Especially preferred embodiments of the invention include sufficient acid such that the pH of the inventive compositions is in the range of 0.3 to 0.7, and especially preferably is about 0.5. Any water soluble or water dispersible organic or inorganic acid may be used at the acid constituent with the inventive composition. Exemplary useful water soluble organic acids include at least two carbon atoms, and include at least one carboxyl group (-COOH) in its structure including one or - 8 more selected from the group consisting of: lactic acid, citric acid, adipic acid, glutaric acid and glycolic acid. Exemplary useful inorganic acids include hydrochloric acid and sulfuric acid. Particularly useful as the acid constituent are one or more acids selected from phosphoric acid, amidosulfomic acids, sulfamic acid, and especially blends of both phosphoric and sulfamic acids. Blends of phosphoric acid and sulfamic acid are particularly preferred for use in the compositions as they have been observed to provide good limescale removal from surfaces, such as lavatory surfaces particularly from sanitary appliances such as toilets. As noted, the acid constituent may be present in any effective amount which is effective in attaining the target pH levels noted above, and amounts in the range of at little as 0.0001%wt. to as much as 15%wt., but preferably the acid constituent is present in amounts of about 5%-12%wt, preferably from about 5% 1 0%wt. based on the total weight of the the multi-phase liquid compositions according to the invention.

The inventive compositions include at least one organic hydrotrope constituent.

Organic hydrotropes useful in the use of the compositions of the present invention include known art hydrotrope compositions. Suitable hydrotropes include salts of aryl sulfonic acids such as naphtyl and benzene sulfonic acids, wherein the aromatic nucleus may be unsubstituted or substituted with lower alkyl groups, such as Cry alkyl groups, especially methyl, ethyl and/or isopropyl groups. Up to three of such substitutents may be present in the aromatic nucleus, but preferably zero to two are preferred. The salt forming cation of the hydrotrope is preferably an alkali metal such as sodium or potassium, especially sodium. However, other water soluble cations such as ammonium, mono-, di- and tri- lower alkyl, i.e., Can alkanol ammonium groups can be used in the place of the alkali metal cations. Exemplary hydrotropes include benzene sulfonates, o toluene sulfonates, m-toluene sulfonates, and p-toluene sulfonates; 2,3-xylene sulfonates, 2,4-xylene sulfonates, and 4,6-xylene sulfonates; cumene sulfonates, toluene sulfonates, wherein such exemplary hydrotropes are generally in a salt form thereof, including sodium and potassium salt forms. Further exemplary hydrotropes include lower alkyl sulfate salts, particularly those having from about one to six carbon atoms in the alkyl group. Particularly preferred is sodium cumene sulfonate.

The one or more organic hydrotropes are present in amounts which promote phase separation, and can be present in any effective amount. These amounts can be as little as 0.1%wt. to as much as 3%wt. based on the total weight of the compositions. Based on the preferred ratios of the two cationic surfactants present however, hydrotropes are desirably present in amount of from about 0.5%wt. to about 1.5%wt., more preferably from about 1%wt. to 1.2%wt.

As noted above, the inventors have found that the degree of separation of the separate aqueous phases when the composition is in a quiescent state is largely dependent upon the amounts of the first, and second cationic surfactants, and the amount of the organic hydrotrope constituent present. Desirably the weight ratios of the total amount of the first and second cationic surfactants with respect to the amount of the organic hydrotrope present is in the ratio of about 1:0.3-1, preferably however the ratio is about 1:0.5-0.8. Desirably the respective volume ratios of the upper phase to lower phase is in the range of 40% - 60%: 60% - 40%, but preferably ratios is in the range of 45% - 55%: 55% - 45%, and most preferably are in about equal volume proportions. However the appropriate adjustment of the amounts of the first and second cationic surfactants, and the amount of the organic hydrotrope constituent present in the formulation can be varied to provide lesser or greater volume ratios than those preferred ratios recited above, and are considered to fall within the scope of the invention.

The inventive compositions also necessarily comprise a thickener constituent which is based on one or more gums, preferably one or more gums selected from xanthan gum and gellan gum. Preferably the thickener constituent consists solely of xantham gum. The designation "xanthan gum" includes treated and modified materials, such as deacetylized xanthan gum, depyruvatized xanthan gum, xanthan gum cross-linked with polyvalent cations, the gum/glyoxal complexes, and the like. In the compositions of the invention, one gum or a mixture of gums may be used. It is known that within certain proportions, mixtures of gums possess a synergy in regard to viscosifying andlor gelling capability. Thus, synergism may be used to advantage in the compositions of the invention.

The thickener constituent may be present in any amount wherein the viscosity of the inventive composition, when the various aqueous phases present are well intermixed, - 10 results in a viscosity of at least 25 cps, more preferably is at least 50 cps, but not in excess of 200 cps, as measured using a Brookfield LV Viscometer using spindle 2, at 60 rpm, operating at room temperature (20 C). Advantageously the thickener constituent is present in any amount with amounts of at least about 0.05 %wt. based on the total weight of the multi-phase liquid composition of the invention, preferably in amounts of 0.05%wt., to 0.5%wt., and most preferably are present in amounts of 0. 1%wt. to 0.2%wt.

While not an essential feature in all embodiments of the inventive compositions, desirably the liquid compositions of the invention comprise at least one coloring agent.

While any coloring agent which may be dispersed in the largely aqueous liquid compositions of the invention may be used, preferred for use are aqueous dispersible or aqueous soluble dyes, and most preferably, when present, the coloring agent is one or more acid stable dyestuffs, particularly acid dyes as defined by the Color Index. Such acid dyes should be selected to have a visible color, preferably one which is attractive to a consumer and which provides a contrast between a liquid phase which contains a coloring agent and any further liquid phases which include little or no coloring agent.

Alternately the acid dyes should be selected to have a visible color, preferably colors which are attractive to a consumer and when the multiphase liquid compositions are in a quiescent state provide a contrast between a liquid phase which contains a coloring agent and any further liquid phases which may include a further coloring agent, or which may include little or no coloring agent. The coloring agent may be present in any amount which is effective in imparting a coloring effect to one or more of the phases of the multi- phase liquid compositions described herein. Amounts from as little as 0. 0001%wt., may be effective for particularly substantive coloring agents, especially for particularly substantive acid dyes. Generally however amounts in the range of 0.0005% to about 0.1 %wt. are advantageously used.

In one aspect of the invention, the present invention relates to compositions which form at least two separate liquid phases when left in a quiescent state, which may be physically shaken to reconstitute the at least two separate phases, which compositions which are useful in providing a cleaning and/or disinfecting treatment of hard surfaces.

Desirably the compositions include at least a first liquid phase which comprises at least 98%wt, but more desirably comprises at least 99.5%wt., and most preferably - 11 substantially all of the coloring agent (when present) in the inventive composition, while the remaining second liquid phase (as well as any further liquid phases) contain less than 2%wt, desirably less than 0.5%wt. and most preferably the remaining second liquid phase (as well as any further liquid phases) are substantially free of the coloring agent.

In a further aspect of the invention, the present invention relates to compositions which form at least two separate liquid phases when left in a quiescent state, which may be physically shaken to reconstitute the at least two separate phases, which compositions which are useful in providing a cleaning and/or disinfecting treatment of hard surfaces.

Desirably the compositions include at least a first liquid phase which comprises at least a first coloring agent, especially one or more acid dyes, the compositions including at least a second liquid phase which includes at least a second coloring agent, especially one or more further acid dyes. In such an aspect of the invention, in its quiescent state, the, multi-phase liquid composition comprises at least two liquid phases each having a; different color. When in its mixed state, the least two liquid phases each having a; different color are mixed to form a third color. According to this embodiment, the presence of at least a third liquid phase which may or may not comprise a further coloring agent, especially an acid dye is also contemplated. I While not an essential feature in all embodiments of the inventive compositions, desirably the liquid compositions of the invention comprise at least one fragrancing agent. Such may be one or more substances or mixtures of substances including those which are naturally derived (i.e., obtained by extraction of flower, herb, blossom or plant), those which are artificially derivedor produced (i.e., mixture of natural oils and/or oil constituents), and those which are synthetically produced substances (odiferous substances). In the present invention, the precise composition of the fragrance constituent is of no particular consequence as long as it may be effectively included as a constituent of the compositions, and have a pleasing fragrance. For those compositions i which are intended to be used in a domestic environment, the fragrance constituent, as well as the other ingredients used in making up compositions of the invention should be cosmetically acceptable, i.e., feature low toxicity or no toxicity, hypoallergenic character, etc. The fragrance constituent may be included in any effective amount. Generally good I - 12- 1 results are obtained when the fragrance constituent is present in amounts of about 0.05% to about 0.5%wt. based on the total weight of the inventive compositions.

The inventive compositions may include one or more optional constituents, particularly one or more further surfactants based on cationic compounds such as compounds based on amine oxides, betaines and sulfobetaines or any other surfactant compounds which exhibit a net positive charge. The presence of other surfactants particularly nonionic, anionic, zwitterionic and amphotheric are advantageously excluded in that they may destabilize the phase separation of the upper and lower layers present.

As is noted above, the compositions according to the invention are aqueous in nature. Water is added to order to provide to 100% by weight of the compositions of the invention. The water may be tap water, but is preferably distilled and is most preferably deionized water. If the water is tap water, it is preferably substantially free of any undesirable impurities such as organics or inorganics, especially minerals salts which are present in hard water which may thus undesirably interfere with the operation of the constituents present in the aqueous compositions according to the invention.

Examples:

The following example compositions representative of the present inventive compositions, including particularly preferred embodiments, which were produced according to the following general protocol: A first aqueous premix is prepared by dispersing the thickener constituent in sufficient water in order to provide a concentration of about 0.5%wt. - 1. 5%wt. of the thickener constituent. This is done by providing the water at room temperature is supplied to a high shear mixer and under operation adding in the thickener until a well blended premix is produced.

A second aqueous premix is prepared by providing the remaining water at room temperature to a suitably sized vessel provided with an electrically driven agitator with a standard agitator head (paddle, or propeller). During stirring the remaining constituents are provided in the following sequence and sufficient time is permitted between each addition step to ensure though mixing prior to the addition of the next constituent: acid 13 constituent, cationic surfactants, fragrance, colorant, organic hydrotrope constituent, and finally the first aqueous premix is added. Stirring is terminated.

A useful technique for quickly evaluating the respective volumes of the upper aqueous phase to the lower aqueous phase may be accomplished by removing an aliquot of the mixture produced and centrifuging it for sufficient time to affect phase separation.

The volume of the two phases formed may be visually evaluated. If desired, the stirring of the mixture can be reinitiated, and further minor amounts of one or more constituents may be added. To increase the volume proportion of the upper layer, the further addition of cationic surfactant is required. To increase the volume proportion of the lower layer, the further addition of organic hydrotrope constituent is required. Using such a technique, specific volume ratios may be attained.

From the foregoing method, that inventive compositions are conveniently produced in a single vessel, and the constituents comprising the first and second layers need not be separated during their manufacture. Rather, the inventive compositions, once mixed and allowed to reach a quiescent state automatically separates into an upper and lower aqueous phase. - 14

:;R 04 | O = 00 1 JNO 1;11d it 141111151 ] : IO Ll O O PL: girl 0 ID PAN INELEP;::I] It 4), O i =C≥'OO: ?4151441]! PO '' Ul O lO O O o N N a O O O O N N Z it To.

6t k h] : a

-T

_ N _ O S to CO O N, N EJ a) O N _ O It' O a) O O, O Z X _] _ Rtt _r LDI O US UD U) , O (D O O, O O 1 a Lit l|: i] i À A) Certain parameters were not tested in the above Table 1, as indicated by "NT".

The identity of the specific constituents listed on Table 1, and their respective commercial sources are indicated on the following Table 2.

TABLE 2

hexadecyltrimethylammoniumchloride ARQUAT 16-50, 50%wt. actives composition (ex. Akzo-Nobel) tallowtrimethyiammoniumchloride, ARQUAT HT-50, 50%wt. actives composition hydrogenated (ex. Akzo-Nobel) phosphoric acid technical grade, 75%wt. actives composition (ex. Albriaht&Wilson) _, sulfamic acid Technical grade, 100%wt. actives composition (ex. Kuang Min (Taiwan) ) sodium cumene sulfonate ELTESOL SC93, 100%wt. actives composition (ex. Albriaht & Wilson) fragrance MECCANO io56, proprietary composition (ex IFF Inc. ) Acid Blue 80 Acid Blue 80, Color Index 61585, 1 %wt actives, (ex. Ciba Specialty Chemicals) Acid Yellow 3 Acid Blue 80, Color Index 61585, 1 %wt actives (ex. BASE) xanthan gum, acid stable KELZAN ASXT, 100%wt. actives (ex. CP Kelco) Water Water from a municipal water supply, as supplied The disclosed features of the invention in the above description and in the claims may essentially be used either individually or in any desired combination for realization of the invention in its various embodiments. It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims. - 17

Claims (9)

1. Claims: 1. A liquid hard surface cleaning composition which includes at

   least a first aqueous phase and at least a second separate aqueous phase said liquid hard surface cleaning composition comprising: a first cationic surfactant; a second cationic surfactant which comprises a fatty alkyl group derived from a naturally occurring source; an organic hydrotrope constituent; a thickener constituent based on one or more gums; an acid constituent; and water; wherein the liquid hard surface cleaning composition, has a pH of 1.5 or less, when well shaken or well stirred, exhibits a viscosity of at least 25 cps and does not exceed about cps, as measured using a Brookfield viscometer using spindle 2, at 60 rpm, operating at room temperature, and wherein the composition will form a first aqueous phase and a second separate aqueous phase when left in a quiescent state.
2. 2. The composition according to claim 1 wherein the first cationic surfactant and the second cationic surfactant are present in weight ratios of about at least 2:1.
3. 3. The composition according to claim 2 wherein the first cationic surfactant and the second cationic surfactant are present in weight ratios of about at least 2.8:1.
4. 4. The composition according to claim 3 wherein the first cationic surfactant and the second cationic surfactant are present in weight ratios of about at least 3:1.
5. 5. The composition according to any preceding claim wherein the weight ratios of the total amount of the first and second cationic surfactants with respect to the amount of the organic hydrotrope present is in the weight ratio of about 1:0.3-1. - 18
6. 6. The composition according to claim 5 wherein the weight ratios of the total amount of the first and second cationic surfactants with respect to the amount of the organic hydrotrope present is in the weight ratio of about 1:0.5-0.8.
7. 7. The composition according to any preceding claim wherein the thickener constituent is selected from xanthan gum and gellan gum.
8. 8. The composition according to any preceding claim wherein the thickener constituent consists solely of xanthan gum.
9. 9. A process for manufacturing a liquid hard surface cleaning composition according to any preceding claim which includes the steps of: forming the composition in a single mixing vessel; and thereafter permitting the composition to separate into at least two visibly distinct aqueous layers. - 19