NZ221105A

NZ221105A - Aqueous solutions of acids or acidic salts thickened with amino derivatives

Info

Publication number: NZ221105A
Application number: NZ221105A
Authority: NZ
Inventors: R N Silvester
Original assignee: R & C Products Pty Ltd
Priority date: 1986-07-17
Filing date: 1987-07-17
Publication date: 1990-01-29
Also published as: EP0253676A2; EG18545A; AU7578787A; IN172271B; PT85352A; ATE64753T1; ES2022360T5; ZM5787A1; DK372187A; EP0253676B1; NO873000D0; ES2022360B3; IE871943L; DK170538B1; MY102871A; GR3002573T3; NO175967C; JPS6324000A; NO175967B; PT85352B

Abstract

A thickened aqueous composition comprising at least one compound acid or acidic salt, a thickening agent which is at least one of the compounds selected from the group consisting of compounds of the formula: <CHEM> wherein R, R1 R2, R3, R4 and R5 are specified substituent groups, and optionally a strong ionic salt, the thickening agent and the acid or acidic salt being together substantially water soluble, and wherein the thickened aqueous composition has a viscosity of not less than 30 centipoise at 25 DEG C when measured with a Brookfield RVT viscometer at 50 rpm using a No. 1 spindle.

Description

<div class="application article clearfix" id="description"> New Zealand Paient Spedficaiion for Paient Number £21105 jjl9.iAN.ia90.. nc £. Patents Form No. 5 NEW ZEALAND PATENTS ACT 1953 ____ • - COMPLETE SPECIFICATION > O s AMINE-ACID THICKENING COMPOSITIONS;' c \\ 17 JUL 19877 X/we, R & C PRODUCTS PTY LIMITED an Australian company incorporated under the laws of the Australian Capital Territory, of 845 Pacific Highway, Chatswood, New South Wales, Australia, hereby declare the invention, for which -5/we pray that a patent may be granted to jae/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 22 1 | ABSTRACT A thickened aqueous composition comprising at least one compound selected from the group consisting of acids and acidic salts, a thickening agent which is at least one of the compounds selected from the group consisting of compounds of the formula: R N R. N VO \ \ R2 or R5 (I) (II) in which R, R^ is a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R^_ is hydrogen, a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R2 is hydrogen, a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R^ is a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, Rr is a substituted alkaryl, aralkyl or or unsubstituted alkyl, aryl/alkenyl group, or and R2 or R4 and R^ when taken together comprise a substituted or unsubstituted heterocyclic ring, provided that if either R, R^ or R2 is an alkyl or alkenyl group derived from a fatty acid obtained from a natural oil or fat or an equivalent synthetic fatty acid, or is an alkaryl group containing from 8 to 12 carbon atoms in the alkyl moiety, then the other substituents are not respectively of the formulae: [A] - H and [A] - H x y where A is either ethoxy or propoxy and x, y are independently 1, 2 or 3, and optionally a strong ionic salt, said thickening agent and the at least one compound selected from the group consisting of acids and acidic salts being together substantially water soluble, and (followed by page lb) ib 2 2 i | o wherein said thickened aqueous composition has a viscosity of not less than 30 centipoise at 25°C when measured with a Brookfield RVT viscometer at 50 rpm using a No. 1- spindle. (followed by page lc^ 227 |05 - lc - The present invention relates to aqueous compositions of acids or acidic salts and more particularly to novel compositions of these acids or acidic salts which include a thickening agent. 5 As used in the specification acidic salts refer to those compounds which in an aqueous solution liberate protons. Aqueous solutions of acids and acidic salts have long been used in compositions for cleaning. Such compositions 10 include toilet bowl cleaners, metal cleaners and brighteners, rust stain removers, denture cleansers, metal descalers, general hard surface cleaners and disinfectants. It has been found that a desirable property of many of the aforementioned compositions is that they have 15 sufficient viscosity so as to allow the composition to be effectively applied to surfaces, for example, by brushing, or to allow the composition to remain in contact with the surface for a sufficient time to act. The latter function has particular relevance to the cleaning of angular 20 surfaces such as those found in toilet bowls where prolonged contact between the composition and the bowl is required for effective cleaning. There are many such compositions known in the art that have the requisite viscosity characteristics. Most 2 5 of such compositions achieve their viscosity through the use of one or more of the following thickening agents:- (a) cellulose derivatives exemplified by sodium carboxymethyl cellulose, hydroxyethyl cellulose, methyl hydroxyethyl cellulose, methyl cellulose, 30 hydroxypropylmethyl cellulose, hydroxybutylmethyl cellulose; (b) gums such as xanthan gum, (c) acrylic acid polymers such as Carbopol (Registered Trade Mark of B.F. Goodrich) 35 (d) nonionic surfactants such as nonyl phenol ethoxylates; (followed by page 2) - 2 - 2 2 1 i (e) poly(ethylene oxide) resins such as Polyox (Registered Trade Mark of Union Carbide); (f) anionic surfactants such as alkylbenzene sulfonates and alkyl ether sulfates; and (g) sodium silicates such as sodium metasilicate. Most of these thickeners whilst able to effectively increase the viscosity of aqueous acid or acidic salt compositions do have some disadvantages in use. The cellulose derivatives and gums tend to hydrolyse on storage which results in a reduction in viscosity of the composition. They are also generally difficult to dissolve, in some cases intensive mixing being required in order to bring them into solution. Acrylic acid polymers are generally only useful in solutions which have a pH near neutral and above. They also tend to hydrolyse on storage and to achieve viscosity, need to be neutralized with a fairly strong alkali. Nonionic surfactants have the disadvantage that usually high levels of about 5-10% are required to achieve satisfactory viscosity, thus making them expensive to use. The poly(ethyleneoxide) water soluble resins also require generally high levels to achieve desirable composition viscosity and additionally, in some acid solutions show significant instability. Sodium silicates are able to produce aqueous acid or acidic salt gel compositions. However, in developing viscosity in a composition, it has been noted that the viscosity generally develops over a long period of time, for example, as much as twelve hours. In commercial manufacturing processes, this is often inconvenient. It is also to be noted that on storage, such gels tend to break down into small pieces which in many instances is undesirable. Other thickening agents and compositions disclosed in 227 JOS " 3 - the art which relate to an aqueous acid and/or acidic salt compositions include:- GB1,443,244 (Reckitt & Colman Products Limited) which discloses a thickening agent of the formula: 5 10 (A) - H for thickening aqueous compositions of mineral acids and acid salts of strong inorganic acids. GB2,071,688 (Jeyes Limited) which discloses as a 15 thickening agent a mixture of: (a) a substantially acid insoluble compound of the formula (I) or (II); and (b) a substantially acid soluble cationic or nonionic surfactant, for thickening aqueous compositions of 20 inorganic acids or acid salts of strong inorganic acids. 30 22 - 4 - H N } 0 *2 (II) US 3,786,091 (Bolsing) which discloses a phosphoric acid containing base paste, produced by preparing a finely divided aqueous dispersion of a long chain amine, preheating this dispersion, introducing preheated phosphoric acid thereinto with vigorous agitation, at elevated temperature until neutral and then stirring the resulting mixture until cold. US 4,021,377 (Borchert et al) which discloses a citric acid-amine reaction product obtained by mixing citric acid and water soluble or water dispersible amine in water until all the citric acid is dissolved. Generally the reaction is accompanied by a rise in temperature to about 40°C over an hour. The resultant solution containing amine salts of citric acid and citric acid amides is viscous. It is to be noted that the concentrations of citric acid and the amines exemplified are particularly high, the amines exemplified being in the range 12-45% W/W and the citric acid, 19.2% W/W. Further, only the amines monoethanolamine, diethanolamine and triethanolamine are exemplified. The present inventor has recognized the difficulties of the prior art thickening agents for such aqueous acid or acidic salt compositions. Accordingly, the present invention seeks to provide alternative compositions to those of the prior art. The present invention consists in a thickened aqueous 221 | - 5 - composition comprising at least one compound selected from the group consisting of acids and acidic salts, a thickening agent which is at least one of the compounds selected from the group consisting of compounds of the 5 formula: (I) (II) 15 in which R, R^ is a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R^ is hydrogen, a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R2 is hydrogen, a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl 20 group, R^ is a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R5 is a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, or R^ and R2 or and R^ when taken together comprise a substituted or unsubstituted 25 heterocyclic ring, provided that if either R, R^ or R2 is an alkyl or alkenyl group derived from a fatty acid obtained from a natural oil or fat or an equivalent synthetic fatty acid, or is an alkaryl group containing from 8 to 12 carbon atoms in the alkyl moiety, then the 30 other substituents are not respectively of the formulae: [A]x - H and Eft]y ~ H where A is either ethoxy or propoxy and x, y are independently 1, 2 or 3, and optionally a strong ionic salt, said thickening agent and the at least one compound selected from the group 35 consisting of acids and acidic salts being together 20 22 - 6 substantially water soluble, and wherein said thickened aqueous composition has a viscosity of not less than 30 centipoise at 25°C when measured with a Brookfield RVT viscometer at 50 rpm using a No. 1 spindle. 5 In a second aspect, the present invention consists in a method of forming a thickened aqueous solution, comprising dissolving in water (a) at least one compound selected from the group consisting of acids and acidic salts (b) a thickening agent which is at least one of the 10 compounds selected from the group consisting of compounds of the formula: *4 15 R - N or R3 N O R2 R5 (I) (II) in which R, R^ is a substituted or an unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R^ is hydrogen, a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R2 is hydrogen, a 25 substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R4 is a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R5 is a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, or R^ and R2, or R4 and R5 when 30 taken together comprise a substituted or unsubstituted heterocyclic ring, provided that if either R, R^ or R2 is an alkyl or alkenyl group derived from a fatty acid obtained from a natural oil or fat or an equivalent synthetic fatty acid, or is an alkaryl group containing 35 from 8 to 12 carbon atoms in the alkyl moiety, then the 221 V - 7 - other substituents are not respectively of the formulae: [A]X~H and [A]y-H where A is either ethoxy or propoxy and X, Y are independently 1, 2 or 3, and optionally (c) a strong ionic 5 salt, said thickening agent and the at least one compound selected from the group consisting of acids and acidic salts being together substantially water soluble, in amounts sufficient to produce a viscosity of not less than 30 centipoise at 25°C when measured with a Brookfield 10 RVT viscometer at 50 rpm using a No. 1 spindle. In the context of this specification, substantially water soluble means that a thickening agent and an acid or acidic salt selected in accordance with the invention, will together either be soluble in water at 25°C or at 15 most will form a hazy solution that does not separate into two phases during normal storage. It will be appreciated that the compositions of the present invention may be readily distinguished over those disclosed in the aforementioned patent application 20 GB2071688 (Jeyes Limited) in that the compositions claimed therein are directed towards substantially acid insoluble amines or amine oxides, which require a substantially acid soluble cationic or nonionic surfactant to achieve thickening. 25 By contrast the present invention is limited to either amines or amine oxides which together with the selected acid or acidic salt are substantially water soluble, without a cationic or nonionic surfactant being required in the case of the amines to achieve solution and 30 thickening, and in the case of the amine oxides, without the use of a cationic, nonionic or anionic surfactant, particularly an alkyl sulphate to achieve solution and thickening. It is also to be noted that in GB2071688 it is stated that neither of the amine, amine oxide, cationic 35 surfactant or nonionic surfactant alone with an aqueous - 8 - ^ m m 22 f 10 V..~ solution of an inorganic acid or acid salt will cause thickening. It will also be appreciated that the aforementioned US 4,021,377 (Borchert et al) does not disclose, nor does 5 it suggest that thickening will occur in compositions envisaged by the present invention without recourse to heating the amine with citric acid to form various reaction products. The present inventor believes that the disclosure in this US patent that the reaction products of 10 citric acid and an amine are viscous in solution was merely an observation by the inventors, and perhaps not unexpected in view of the high concentration of reactants employed. In fact, there is no disclosure in this US patent that the inventors are aware that levels of amines 15 as low as those preferred and exemplified in the present invention will form thickened compositions with acid or acidic salt solutions. The real thrust of this patent is a method of producing a concentrated solution of desired reaction products which happen in this high concentration 2 0 to be viscous. In order to demonstrate this, the present inventor produced aqueous solutions containing 5% w/w citric acid anhydrous and 2% w/w mono-, di- or tri-ethanolamine. No thickening was noted in any of these solutions. 25 Similarly, in US 3,786,091 (Bolsing), it is taught that it is necessary to obtain the reaction products between the selected amine and phosphoric acid by heating them together to produce a paste. Thus, Bolsing in the simplest embodiment of his 30 invention disperses the selected amine in water, heats the dispersion to between 40°C and 100°C and then adds to it at least a neutralising amount of phosphoric acid, preheated to between 40°C and 120°C. Stirring is continued until the temperature falls to between 5°C and 35 25°C and the resultant composition is a paste consisting ? 7 1 - 9 - of the reaction products between phosphoric acid and selected amine. Bolsing also discloses that other acids such as sulphuric, hydrochloric, tartaric, oxalic, hydrofluoric and nitric may be used as an additive to a 5 base paste of his invention. He further discloses that other amines may also be used as additives. The present invention may be distinguished over Bolsing when it is considered that the amines of the Bolsing invention must be derivatives of substituted or 10 unsubstituted hydrocarbons having 8-24 carbon atoms, the selected amine must be reacted by heating with phosphoric acid to achieve viscosity and there is no hint or suggestion that acids other than phosphoric acid are operative. Additionally, with respect to acidic salts, it 15 is noted that Bolsing refers to ammonium chloride as an auxilliary. In contrast, the present invention teaches that thickening can be achieved with a range of acids and acidic salts, no heating is required to obtain thickening 20 and the present inventor believes that amines additional to those of Bolsing are operative. It is preferred that in the above formulae I or II, either of the groups R or R^ contains at least six carbon atoms. More preferably, either of the groups R or 25 R-j contains from 8 to 24 carbon atoms. Most preferably either of the groups R or R3 contains from 8 to 24 carbon atoms in an unsubstituted alkyl or alkenyl group. Preferably, the groups Rand R2 are independently a hydrogen atom or a lower unsubstituted 30 alkyl group, where lower refers to groups containing 1 to 4 carbon atoms or a substituted alkyl group. More preferably the groups R^ and R2 are independently a hydrogen atom or a lower unsubstituted alkyl group. Most preferably, the groups R1 and R2 are independently a 35 hydrogen atom or a methyl group. • • 22 f f Preferably, the groups R4 and R5 are independently a lower unsubstituted alkyl group, where lower refers to groups containing 1 to 4 carbon atoms or a substituted alkyl group. More preferably, the groups and R^ 5 are independently a lower substituted or unsubstituted alkyl group. Most preferably the groups R^ and R^ are independently a methyl, or hydroxyethyl, or hydroxy propyl group. Preferred thickening agents of the present invention 10 that are primary amines include Farmin 0 (Farmin is a registered trade mark of Kao Soap Co.) or Genamin OL-IOOD (Genamin is a registered trade mark of Hoechst), both of which are mainly oleylamine and Farmin T or Genamin TA100D, both of which are tallow fatty amine distilled. 15 These thickening agents are able to thicken organic acids including formic, acetic, DL lactic, adipic, glvcollic, malonic, succinic, pentetic, ascorbic, chloroacetic, citric and propionic acids. In some cases a small addition of a strong ionic salt such as sodium chloride is 20 required to achieve adequate composition viscosity in the preferred concentration range of thickening agent. Naturally, increasing the concentration of thickening agent will increase viscosity in many cases. However, because of the relatively low cost of such salts, it is 25 preferred to use a mixture of thickening agent and strong ionic salt to achieve the desired viscosity. However, it must also be considered that the addition of extra thickening agent may increase the pH and thereby decrease the efficiency of a composition. 30 Preferred thickening agents of the present invention that are tertiary amines include Genamin S0302D (dimethyl soya bean oil fatty amine distilled) and Genamin TA302D (dimethyl tallow fatty amine distilled). These amines are able to thicken organic acids including citric acid, L 35 tartaric acid, formic acid, DL malic acid, acetic acid, DL - 10 vf 22 11 lactic acid, adipic acid, maleic acid, ethylenediamine-tetraacetic acid, glvcollic, malonic, succinic and propionic acid and inorganic acids including sulfamic acid, phosphoric acid, boric, hydrofluoric and sulphuric 5 acid. Generally, for reasons outlined above, these amines require the addition of a strong ionic salt, such as sodium chloride in order to achieve adequate composition viscosity in the preferred concentration range of thickening agent. 10 Preferred thickening agents of the present invention that are tertiary amines able to thicken acidic salts include Genamin TA302D and Genamin S0302D. Genamin TA302D able to thicken aqueous solutions of monosodium citrate, and potassium hydrogen tartrate with the addition 15 of a strong ionic salt such as sodium chloride. Genamin S0302D is able to thicken aqueous solutions of aluminium sulphate, sodium hydrogen sulphate, sodium dihvdroyen orthophosphate, disodium ethylenediaminetetraacetate and aluminium potassium sulphate with a small addition of a 20 strong ionic salt such as sodium chloride required in some cases; the sodium chloride being required to achieve adequate composition viscosity as previously described. Preferred thickening agents of the present invention that are primary amines able to thicken acidic salts 25 include farmin 0, genamin OL-IOOD, Farmin T and Genamin TA-100D. These amines are able to thicken aqueous solutions of aluminium acetate. Other amines considered by the present inventor to be within the scope of this invention include: Onamin 1416 (N-alkvl C24-C"16 amine) Farmin DMON (Dimethyl oleyiamine), Kao-DBA (dimethyl benzylamine); N-lauryl morpholine; N-Coco morpholine; 35 N-cetylmorpholine; and 22 ! i ( - 12 - Genamin 14R302D (tetradecyl dimethylamine ciscilled) ; Genamin 16R302D (hexadecvl dimethylamine distilled); 5 Genamin 14R100D (tecracecvla.nine distilled); Genamin 16R100D (hexadecvlamine distilled); The following amines obtainable from KenoGard-Amine 2M0L (dimethyloleylamine) 10 Amine 28 (dioctvlamine) Amine 210 (didecylamine) Amine M28 (methyldioctvlamine) and Amine M210 (methyldidecvlamine)- It is to be noted that the abovementioned preferred 15 amines are in fact mixtures of a number of amines with one amine being predominant. The present inventor believes that the predominant amine may function to solubilize the minor amines in compositions of the present invention. For example, Farmin O is predominantly olevlamine 20 having an approximate alkyl content of 6% , 13% C^g and 81% C^g, whilst Genamin S0302D has an approximate average chain length distribution of 2% Cj_4, 15% C^g and 83% C18 and Genamin TA302D has an approximate average chain length distribution of 5% 30% C-,g 25 and 65% C^g. Preferred thickening agents of the present invention that are amine oxides include Aromox T/12 (bis[2-hydroxyethyl]tallow amine oxide) and Ammonyx MCO (mixture of myristyl and cetyl dimethyl amine oxides). 30 Aromox is a trade mark of Armour Hess and Ammonyx is a trade mark of Onyx Chemicals Co. Aromox T/12 is able to thicken citric, phosphoric and sulphuric acids. An example of a composition containing Ammonyx MCO was prepared to contain: 35 Ammonyx MCO (30% active) 6.67% - 13 - 22110 Sulphuric acid 3-3 3% w/w Sodium chloride 0.7% w/w Water 83.8% w/w It was observed that whilst the viscosity was not determined, it appeared to be thick and viscous. Futhermore, it is to be noted that whilst Ammonyx MCO is water soluble, its viscosity is water thin, even in a 6.57% acueous ,solution accitionallv containing solelv 2% socium cmorice. As in the case of the amines of the invention, the preferred amine oxides falling within the scope of this invention are mixtures of amine oxides. Thus, Aromox T/12 has an average chain length distribution of 1% C.,,, 3% C^^, 27% C^g, 24% 1% CI4 (unsat), 4% C^g (cnsat) 39% C-, g (unsat) , 1% C^g (double unsat) . Similarly, the amine oxides of the invention, may require a small addition of a strong ionic salt to achieve adequate composition viscosity, as previously described. Other amine oxides considered by the present inventor to be within the scope of this invention include: bis {2-hydroxy ethyl) soya bean oil amine oxide; dimethyl tallow amine oxide; dimethyl olevl amine oxide; dimethyl soya bean oil amine oxide; bis (2-hydroxy ethyl) oleyl amine oxice. Additionally, amines or amine oxides of the invention may be generally derived from natural or synthetic sources of tallow, soya bean oil, oleic acid, palmitic acid, mvristic acic, linoleic acid, linolanic acid, ricinoleic acid, hexadecenoic acid. Generally the acids to which the present invention is directed include inorganic acids such as sulphuric hydrofluoric, boric, sulphamic and phosphoric acids and the organic acids Formic, acetic, DL lactic, propionic, citric, DL malic, L tartaric, adipic, maleic and ethyleneciaminetetraacetic acid, malonic, clycolli(^^tW P , o\\ fe-6 NOV 1989"j 2 2 f f - 14 - succinic, ascorbic, pentetic and chloroacetic acids. The acidic salts to which the present invention is directed include the acid salts of inorganic or organic acids such as monosodium citrate, sodium hydrogen 5 sulphate, sodium dihydrogen orthophosphate, disodiura ethylenediaminetetraacetate, aluminium acetate and potassium hydrogen tartrate, aluminium sulphate and aluminium potassium sulphate. The concentration of acid or acidic salt may be 10 varied over a wide range depending on the end use of the composition. In some cases, particularly where a strong acid such as hydrofluoric acid is used and a near neutral product is required, the concentration of acid or acidic salt may be as low as 0.01% w/w. 15 In other cases, the concentration of acid or acidic salt may be in excess of 90%. Generally, the concentration of acid or acidic salt will lie in the range of from 0.1 to 30% w/w. In use, generally the thickening agent will be 20 present in a concentration in the composition of from 0.1 to 10% w/w. Preferably, the concentration in the composition will lie in the range of from 0.4 to 5.0% w/w. In order to achieve a desired viscosity in the composition, the concentration of the thickening agent may 25 be varied appropriately. However, in some cases, it has been found that it is not possible to achieve sufficient composition viscosity for some applications. In such cases, the addition of a salt which has high ionic strength has been found to enhance the viscosity of these 30 compositions. In most cases however, the concentration of thickening agent and high ionic strength salt will be optimized in order to produce a cost effective composition of the desired viscosity. Generally, the ionic salts will be selected from alkali metal halides or sulphates and 35 ammonium halides or sulphates. Suitable such salts - 15 - 227705 include sodium chloride, sodium sulphate, potassium sulphate, potassium chloride, ammonium chloride and the like. Alternatively, the present inventor believes that 5 certain long chain quaternary ammonium compounds may achieve similar thickening to the aforementioned salts. An example is Arquad 16-50 which is hexadecyltrimethyl ammonium chloride^or Arquad S-50 which is a mixture of octadecanvl and oc:acecat:ieny 1 trimethyl ammonium chloride. Arcuad is a trade mark of Armour Hess Chemicals. 10 It has further been found that in some cases whilst the composition is thick, clear and stable at room temperature, in order to achieve a satisfactory upper and lower cloud point for a composition, it is necessary to add another ingredient such as a salt with a strong ionic 15 effect of the type mentioned above, a cationic, nonionic or amphoteric surfactant or a solvent miscible with the isonrooanol composition, for example ethanol, butyl Icinol,/and the like (Icinol is a trade mark of ICI) and Dowanol DPM (dipropvleneglvcol methvlether. Dowanol is a trade mark 20 of Dow Chemicals). Such an addition of salt, surfactant or solvent insures that a composition will remain stable under hot and cold weather conditions. A variety of other ingredients may be added to compositions of the invention depending on their end use. 25 Thus, germicides, surfactants including anionic, nonionic, cationic and amphoteric, sequestering agents, corrosion inhibitors, perfumes and colouring agents may be added. A principal advantage of the present invention is that an aqueous acid or acidic salt solution may be readily 30 and easily thickened. Generally the steps of obtaining such thickened compositions will be - (a) add an appropriate amount of acid or acidic salt to water and stir to dissolve, (b) add a thickening agent of the present invention to the solution and stir until dissolved and (c) 35 add other ingredients if required, stirring to dissolve. - 16 - 2 2 1 i It will be appreciated that since the thickening agent of the present invention is defined to be soluble in the selected acidic salt or acid solution, and as it will generally be easily wet, the step (b) above will be 5 relatively rapid unlike many of the prior art thickening agents, which whilst they may be soluble are frequently difficult to wet. Other advantages of the thickening agents of the present invention are that they are relatively inexpensive 10 and in use produce smooth, homogeneous immediate thickening. Furthermore, thickened compositions are stable with respect to viscosity. For example, the present inventor has found that a citric acid composition thickened with Farmin O had no substantial change in 15 viscosity when stored at room temperature for 12 months. A still further advantage is that the present inventor has found that the compositions of the invention have some surfactant and corrosion inhibition properties. The former finding means that water immiscible substances 20 such as fragrances may be directly solubilized in a composition of the invention without requiring the addition of emulsifiers or auxilliary solvents, and in compositions in which the surface active properties are required, potentially less or no additional surfactant 25 would be required. The present inventor has also found that if only sufficient of an acid or an acidic salt is present to just dissolve a thickening agent of the present invention, then a composition of near neutral pH may be obtained. Thus, 30 Farmin O may be used to thicken lactic acid at a pH of 6.5. The advantage of this finding is that it may be used in aqueous liquid cleaners in general. The present inventor has further found that an acid or acidic salt which is usually considered to be water 35 insoluble at room temperature may be brought into solution * - 17 - 22 1 1 Q through the use of a thickening agent of the present invention, with thickening occurring. The viscosity may be increased through the use of a strong ionic salt such as sodium chloride. To prepare such compositions, the 5 acid is dispersed in the water and the thickening agent added with mixing. It is observed that as the acid and thickener go into solution, the solution increases in viscosity. Preferred compositions of this type include 10 ethylenediaminetetraacetic acid with Genamin S0302D as the thickening agent, potassium hydrogen tartrate with Genamin TA302D as thickening agent and pentetic acid with Farmin O as thickening agent. Hereinafter are a number of examples, 1 to 60, of the 15 present invention, together with comparative examples 1A and IB, in which the viscosity, in centipoise, of each was determined using a Brookfield RVT viscometer using a spindle and speed as appropriate at 25°C. Note that the thickening agent is asterixed in each case. 20 All of these examples (except Nos. 27, 46 and 51) were produced by bringing the acid or acidic salt into solution, adding the thickening agent and mixing until dissolved, and then adding the other ingredients with mixing until dissolved. 25 Examples 27, 46 and 51 were prepared by dispersing the acid or acid salt in water, adding the thickening agent and mixing until solution occurred, followed by sodium chloride (if required) until a satisfactory viscosity was achieved. Note that all examples were prepared under normal laboratory conditions. - 18 - 22 Example 1 Citric Acid Anhydrous * Farmin 0 Water Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) pH Comparative Example 1A Water viscosity Spindle 1 Spindle 2 % w/w 5.0 1.8 93.2 670 cps 2.2 Speed 20 rpm Speed 50 rpm Speed 20 rpm Speed 50 rpm Example IB Aqueous 5% w/w Citric Acid Anhydrous solution Viscosity Spindle 2 Speed 20 rpm Speed 50 rpm Example 2 Citric Acid Anhydrous Farmin 0 Vantoc CL (Benzalkonium Chloride BP 50% w/v - Vantoc is a trade mark of ICI) Sodium Chloride Perfume Dye Water Viscosity (Spindle No. 1, speed 50 rpm, at 25 C) pH % w/w 5.0 2.0 2.2 0.7 0.2 0.005 89.9 54 cps 2.3 3.5 cps 6.5 cps 0 cps 5.5 cps 0 cps 5. 5 cps f - 19 - ^2 ? j 05 Example 3 % w/w ■""" DL-Lactic Acid 88% 5.0 * Farmin 0 2.0 Sodium Chloride 0.3 Water 92.7 Viscosity (Spindle No. 2, > speed 20 rpm, at 2 5°C) 820 cps pH 2.9 Example 4 % w/w DL-Lactic Acid 88% 5.0 * Farmin 0 2.0 Vantoc CL (Benzalkonium Chloride BP 50% w/v - Vantoc is a trade mark of ICI) 0.4 Sodium Chloride 0.35 Perfume 0.2 Dye 0.005 Water 92.05 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 530 cps v'' pH 2.9 Example 5 % w/w DL-Lactic Acid 88% 0.85 * Farmin 0 2.0 Sodium Chloride 0.1 Water 97.05 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 740 cps pH 6.5 - 20 - Example 6 Formic Acid 88% * Farmin 0 Sodium Chloride Water Viscosity (Spindle No. 1, speed 50 rpm, at 25°C) pH Example 7 Formic Acid 88% * Genamin TA100D Sodium Chloride Water Viscosity (Spindle No. 1, speed 50 rpm, at 2 5°C) pH ExamDle 8 Acetic Acid (Glacial) * Farmin 0 Sodium Chloride Water Viscosity (Spindle No. 2, speed 50 rpm, at 25°C) pH % w/w 4.1 2.0 0.05 93.85 58 cps 2.5 % w/w 4.1 2.0 0.05 93.85 30 cps 2.45 % w/w 4.7 2.0 0.25 93.05 160 cps 3.6 - 21 - Example 9 % w/w Acetic Acid (Glacial) 4.7 * Farmin 0 2.0 Vantoc CL (Benzalkonium Chloride BP 50% w/v - Vantoc is a trade mark of ICI 0.4 Sodium Chloride 0.35 Perfume 0.2 Dye 0.005 Water 92.35 Viscosity (Spindle No. 2, speed 50 rpm, at 25°C) 180 cps pH 3.6 Example 10 % w/w Acetic Acid (Glacial) 4.7 * Genamin TA100D 2.0 Sodium Chloride 0.3 Water 93.0 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 660 cps pH 3.6 Example 11 % w/w Propionic Acid 5.8 * Farmin 0 2.0 Sodium Chloride 0.3 Water 91.9 Viscosity (Spindle No. 1, speed 50 rpm, at 25°C) 58 cps pH 3.7 Example 12 % w/w Citric Acid Anhydrous 5.0 * Genamin S0302D 2.0 Sodium Chloride 2.0 Perfume 0.2 Water 90.8 Viscosity (Spindle No. 2, speed 50 rpm, at 25°C) 220 cps pH 2.3 5 Example 13 % w/w Citric Acid Anhydrous 5.0 * Genamin TA302D 2.0 Sodium Chloride 2.0 Perfume 0.2 Water 90.8 Viscosity (Spindle No. 2, speed 50 rpm, at 25°C) 240 cps pH 2.35 Example 14 % w/w L-Tartaric Acid 5.9 * Genamin S0302D 2.0 Sodium Chloride 1.4 Perfume 0.2 Dye 0.005 Water 90.5 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 625 cps pH 2.15 m 221105 - 23 - Example 15 % w/w L-Tartaric Acid 5.9 * Genamin TA302D 2.0 Sodium Chloride 1.4 Perfume 0.2 Water 90.5 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 1065 cps pH 2.1 Example 16 % w/w Formic Acid 88% 4.1 * Genamin S0302D 2.0 Sodium Chloride 1.3 Dye 0.005 Water 92.6 viscosity (Spindle No. 2, speed 50 rpm, at 25°C) 160 cps pH 2.4 Example 17 % w/w Formic Acid 88% 4.1 * Genamin TA302D 2.0 Sodium Chloride 1.6 Water 92.3 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 500 cps pH 2.5 - 24 - Example 18 DL-Malic Acid Genamin S0302D Sodium Chloride Dye Water Viscosity (Spindle No. 1, speed 20 rpm, at 25°C) pH % w/w 5.2 2.0 1.6 0.005 91.2 97 cps 2.45 22!105 Example 19 DL-Lactic Acid 88% Genamin 16R302D Sodium Chloride Perfume Dye Water Viscosity (Spindle No, 1/ speed 20 rpm, at 25 C) pH % w/w 5.0 2.0 2.0 0.2 0.005 88.8 100 cps 2.75 Example 20 Sulphamic Acid Genamin S0302D Sodium Chloride Water Viscosity (Spindle No. 1, speed 50 rpm, at 25°C) pH % w/w 7.6 2.0 1.1 89.3 77 cps 0.8 - 25 - Example 21 Sulphamic Acid Genamin TA302D Sodium Chloride Water Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) DH % w/w 7.6 2.0 1.7 88. 7 390 cps 0.9 22 ] ?05 Example 22 Phosphoric Acid 85% Genamin S0302D Sodium Chloride Water Viscosity (Spindle No. 2, speed 50 rpm, at 25°C) pH % w/w 5.9 2.0 1.1 91.0 170 cps 1.35 Example 23 Phosphoric Acid 85% Genamin TA302D Sodium Chloride Water Viscosity (Spindle No. 2, speed 20 rpm, at 25 C) PH % w/w 5.9 2.0 1.5 90. 6 395 cps 1.35 Example 24 Sulphuric Acid conc. Genamin S0302D Water Viscosity (Spindle No. 2, speed 2 0 rpm, at 25°C) pH % w/w 3.83 2.0 94.17 890 cps 0.85 - 26 - Example 25 % w/w Sulphuric Acid conc. 3.83 * Genamin TA302D 2.0 Water 94.2 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 37 5 cps pH 0.9 Example 26 % w/w Monosodium Citrate 8.35 * Genamin TA302D 2.0 Sodium Chloride 2.0 Water 87.65 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 430 cps pH 3.75 Example 27 % w/w Ethylenediaminetetraacetic Acid 0.8 * Genamin S03 02D 2.0 Sodium Chloride 1.7 Water 95. 5 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 730 cps PH 5.65 Example 28 % w/w ai2 (so4)3.16h2o 6.7 * Genamin S030 2D 2.0 Sodium Chloride 0.3 Water 91.0 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 390 cps pH 3.65 221105 - 27 - Example 29 A1K (S04)2.12H20 * Genamin S0302D Sodium Chloride Water Viscosity (Spindle No. 2, speed 50 rpm, at 25°C) pH Example 30 Sodium Hydrogen Sulphate * Genamin S0302D Water Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) PH Examole 31 Sodium Dihydrogen Orthophosphate Dihydrate * Genamin S0302D Water Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) pH Example 32 Adipic Acid * Genamin S0302D Sodium Chloride Water Viscosity (Spindle No. 2, speed 50 rpm, at 25°C) pH % w/w 10.0 2.0 0.1 87.9 240 cps 3.75 % w/w 9.5 2.0 88.5 1500 cps 0.9 % w/w 12.0 2.0 86.0 585 cps 5.2 % w/w 1.0 2.0 2.0 95.0 255 cps 4.55 - 28 - / / ? " n e W Example 35 22 1 Example 33 % w/w Adipic Acid 1.4 * Farmin O 2.0 Water 96.6 Viscosity (Spindle No. 2, speed 5 rpm, at 25°C) 4095 cps pH 3.95 Example 34 % w/w Maleic Acid 1.0 * Genamin S0302D 2.0 Sodium Chloride 0.5 Water 96.5 Viscosity (Spindle No. 1, speed 20 rpm, at 25°C) 113 cps pH 2.6 % w/w Disodium Ethylenediaminetetraacetate 6.6 Genamin S0302D 2.0 Sodium Chloride 1.7 Water 8 9.7 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 785 cps pH 5.8 - 29 - Example 36 DL-Lactic Acid 88% * Genamin TA100D Sodium Chloride Water Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) ph Example 37 Formic Acid 88% * Farmin 0 Vantoc CL (Benzalkonium Chloride BP 50% w/v - Vantoc is a trade mark of ICI Sodium Chloride Perfume Dye Water Viscosity (Spindle No. 1, speed 50 rpm, at 25°C) pH % w/w 8.0 2.0 0.6 89.4 1255 cps 2.7 % w/w 4.1 2.0 0.4 0.15 0.2 0.005 93.15 89 cps 2.5 Example 38 Formic Acid 88% Farmin O Vantoc CL (Benzalkonium Chloride BP 50% w/v - Vantoc is a trade mark of ICI Sodium Chloride Perfume Dye Water Viscosity (Spindle No. 2, speed 20 rpm, at 25 C) pH % w/w 5.5 2.0 0.4 0.2 0.2 0.005 91.7 450 cps 2.05 - 30 - Example 39 % w/w Glycollic Acid 70% 8.5 * Farmin 0 2.0 Sodium Chloride 0.2 Water 89.3 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 660 cps pH 2.5 Example 40 % w/w Glycollic Acid 70% 8.5 * Genamin SO 302D 2.0 Sodium Chloride 1.8 Water 87.7 Viscosity (Spindle No. 2, speed 50 rpm, at 25°C) 290 cps pH 2.3 Example 41 % w/w Malonic Acid 4.0 * Farmin 0 2.0 Water 94.0 Viscosity (Spindle No.2, speed 50 rpm, at 25°C) 185 cps pH 2.0 Example 42 % w/w Malonic Acid 4.0 * Genamin SO 302D 2.0 Sodium Chloride 1.6 Water 92.4 Viscosity (Spindle No. 1, speed 50 rpm, at 25°C) 69 cps pH 1.9 Example 4 3 Succinic Acid * Farmin O Sodium Chloride Water Viscosity (Spindle No. 2, speed 50 rpm, at 25°C) pH Example 44 Succinic Acid * Genamin SO 302D Sodium Chloride Water Viscosity (Spindle No. 1, speed 50 rpm, at 25°C) ph Example 4 5 L(+)-Ascorbic Acid * Farmin O Sodium Chloride Water Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) ph Example 46 D.T.P.A.(Pentetic Acid) * Farmin O Water Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) pH % w/w 4.6 2.0 0.1 93.3 230 cps 3.1 % w/w 4.6 2.0 2.4 91.0 105 cps 3.1 % w/w 13.75 2.0 0.5 83.75 705 cps 2.9 % w/w 1.3 2.0 96.7 1185 cps 3.2 - 32 - Example 4 7 % w/w Chloroacetic Acid 8.6 * Farmin 0 2.0 Water 89.4 viscosity (Spindle No. 1, speed 50 rpm, at 25°C) 96 cps pH 1.7 Example 48 % w/w Hydrofluoric Acid 50% 3.1 * Genamin SO 302D 2.0 Sodium Chloride 0.6 Water 94.3 Viscosity (Spindle No. 2, speed 50 rpm, at 25°C) 370 cps pH 1.2 Example 4 9 % w/w Boric Acid 5.0 * Genamin SO 302D 2.0 Sodium Chloride 1.4 Water 91.6 Viscosity (Spindle No. 1, speed 20 rpm, at 25°C) 280 cps pH 6.2 Example 50 % w/w Aluminium Acetate 5.3 * Farmin O 2.0 Water 92.7 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 1055 cps pH 5.2 - 33 - Example 51 % w/w Potassium Hydrogen Tartrate 1.1 * Genamin TA 302D 2.0 Sodium Chloride 0.7 Water 96.2 Viscosity (Spindle No. 1, speed 50 rpm, at 25°C) 78 cps pH 6.3 Example 52 % w/w Phosphoric Acid 85% 5.9 * Aromox T/12 4.0 Sodium Chloride 1.0 Water 89.1 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 395 cps pH 1.5 Example 53 % w/w Sulphuric Acid conc. 8.0 * Aromox T/12 4.0 Water 88.0 Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) 380 cps pH 0.7 Example 54 % w/w Citric Acid Anhydrous 5.0 * Aromox T/12 4.0 Sodium Chloride 2.0 Water 89.0 Viscosity (Spindle No. 1, speed 20 rpm, at 25°C) 160 cps pH 2.5 (followed by page 33a) Sxaao-e 33 Sulphuric Acid cor.c. * Aaaonyx MCO (30% active) Sodium Chloride Water Viscosity (Spindle No. 1, speed 20 rpm, at 25°C) pH 33a 221105 % w/w 3.83 5.67 0.60 83.9 130 cps 0.55 Sxaaole 5 5 Sulphuric Acid conc. * Genamin 14R3022 * Gen.aniin 15X3022 Sodium Chloride Water Viscosity (Spindle No. 1, =0, speed 20 rpm, at 2 5 C) ?n % w/w 3.83 1.00 1.00 3.00 91.17 212 cps 0.4 Sxamole 57 Sulphuric Acid cor.c. » Genamin 153302D Wa te r Viscosity (Spindle No. 2, speed 20 rpm, at 25°C) % w /w t • t 2.0 90.3 156 cps 0.15 Sxamole 5 9 Hydrochloric acid 3C% technical * Genaain 14R3C2D Sodium Chloride Water Viscosity (Spindle No. 1, speed 50 rpn, at 25°C) % w/w 9.5 2.0 3.0 35.5 .0 5 cps 0.1 (relieved by pace 33b) 53b Zxanole 59 Hydrochloric acid 30% technical * Genaain TA302D Water Viscositv (Soir.dle No. 2, speed 50 r?m, at 25°C) oH Sxaaole SO Hydrochloric acid 3 0% technical * Anaortyx MCO Water Viscosity (Spindle No.l, speed 20 rpm, at 25°C) 287 cps pH % w/w 5 3.0 2.0 45.0 33 0 cps % w/w 9.5 6.57 33.83 0.2 f \ fcllcvsc by pace </div>

Claims

<div class="application article clearfix printTableText" id="claims"> - 34 - It is to be noted that the viscosity of Example 1, when compared with the viscosity of water (1A) and 5% w/w citric acid (IB), is substantially greater. A comparison with an aqueous solution of the thickening agent in this case was not possible as the thickening agent is water insoluble. The examples 1 to 60 disclosed herein may be used for example as toilet bowl cleaners, metal cleaners and brighteners and the like as well as applications such as gel batteries. - 35 - 221105 WHAT WE CLAIM IS:

1. A thickened aqueous composition having a viscosity of not less than 30 centipoise at 25°C when measured with a Brookfield RVT Viscometer at 50 rpm using a No.l spindle, said composition including at least one compound selected from the group consisting of acid and acidic salts, optionally a strong ionic salt and an effective amount of a thickening agent which is the only agent required to impart said viscosity and is at least one of the compounds selected from the group consisting of either compounds of the formula: Ri *a |1 ,4 3 N R N" \ 0 \ ■ 3 \ R-, or R_ compounds of 3 the formula CD (Hi are each in which R and / a substituted or unsubstituted alkyl, aryl, alkaryl,. aralkyl or alkenyl group, Rt is hydrogen, a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R2 is hydrogen, a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R^ is a substituted or unsubstituted alkyl, aryl, alkarvl, aralkyl or alk^nvl crouo, Rq „is a substituted a-^arvl, a'raixwl or or unsubstituted alkyl, aryi/alkenyi group, or R-, and R2 or R^ and R^ when taken together with nitrogen comprise a substituted or unsubstituted heterocyclic ring, provided that if either R, R^ or R2 ^-s an alfcyl or alkenyl group derived from a fatty acid obtained from a natural oil or fat or an equivalent synthetic fatty acid, or is an alkaryl croup containing from 8 to 12 carbon atoms in the alkyl moiety, then the other substituents are not respectively of the forniulae: — [A] - 3 and-[A]v - 3 .*• where A is either ethoxy or propoxy and x, y are independently 1, 2 or 3, said thickening agent and the at least one comoo.u5d selected from the croup consisting of acics and acidic salts being together substantially water soluble. "' * /:-s? £ <* ~ -L J. U C*

2. A composition as in claim 1, wherein the thickening agent is water insoluble.

3. A composition as in claim 1 or 2, wherein either tne group the group R or/R^" contains at least six carbon atoms.

4. A composition as in claim 3, wherein either - the group R or/^ contains from eight to twenty four carbon atoms.

5. A composition as in any one of claims 1 to 4, wherein the carbon atoms in the group R or R-j are in an unsubstituted alkyl or alkenyl group.

6. A composition as in claim 5, wherein R or R3 is derived from either a natural or synthetic source of tallow, soya bean oil, oleic acid, palmitic or myristic acid.

7. A composition as in claims 4 or 5, wherein R or R^ is derived from either a natural or synthetic source of linolenic, ricinoleic, linoleic, hexadecenoic acid.

8. A composition as in any one of claims 1 to 7, wherein the groups R^ and R., are independently a hydrogen atom, a lower unsubstituted alkyl group containing one to four carbon atoms, or a substituted alkyl group.

9. A composition as in claim 8 wherein the groups R^ and R2 are independently a hydrogen atom or a lower unsubstituted alkyl group.

10. A composition as in claim 9, wherein the groups R-, and R2 are independently a hydrogen atom or a methyl group.

11. A composition as in any one of claims 1 to 7 wherein 1 ""1G^ °cs rt^ V the groups and R-~are>a "lower*unsubstituted alkyl group containing one to four carbon atoms or a substituted alkyl group.

12. A composition as in claim 11 wherein the groups 3, 22 j i u and R5 are independently a lower substituted or unsubstituted alkyl group.

13. A composition as in claim 12, wherein the groups R4 and Rg are independently a methyl, hydroxyethyl or hydroxypropyl group.

14. A composition as in any one of claims 1 to 13 wherein the thickening agent is a mixture of compounds of the formula I or a mixture of compounds of the formula II.

15. A composition as in any one of claims 1 to 14 wherein the acid is selected from the group consisting of phosphoric, sulphuric, boric, sulphamic, tartaric, citric, lactic, formic, acetic, glycollic, pentetic, ethylenediaminetetraacetic, propionic, malic, adipic, maleic, malonic, succinic, hydrofluoric, ascorbic and chloroacetic acids.

16. A composition as in any one of claims 1 to 14, wherein the acidic salt is selected from the group consisting of monosodium citrate, sodium hydrogen sulphate, sodium dihydrogen orthophosphate, disodium ethylenediaminetetraacetate, aluminium potassium sulphate, aluminium acetate, potassium hydrogen tartrate and aluminium sulphate.

17. A composition as in any one of claims 1 to 16, wherein the concentration of thickening agent is in the range of from 0.1 to 10% w/w.

18. A composition as in any one of claims 1 to 16, wherein the concentration of thickening agent is in the range of from 0.4 to 5.0% w/w.

19. A composition as in any one of claims 1 to 18, wherein the concentration of acid or acidic salt is not less than 0.01% w/w.

20. A composition as in any one of claims 1 to 18, wherein the concentration of acid or acidic salt is in the range of from 0.1 to 30% w/w.

21. A composition as in any one of claims 1 to 20, -4, 22'* 05 - 38 - additionally including a perfume, dye, sequestering agent, surfactant or bactericide.

22. A composition as in claim 21, wherein the bactericide is a quaternary ammonium compound.

23. A composition as in any one of claims 1 to 22, wherein the strong ionic salt is selected from the group consisting of alkali metal halides or sulphates and ammonium halides or sulphates.

24. A composition as in any one of claims 1 to 22, wherein the strong ionic salt is a long chain quaternary ammonium compound.

25. A composition as in any one of claims 1 to 24, further including a compound effective in adjusting the upper and/or lower cloud point of the composition.

26. A composition as in claim 25, wherein the compound is selected from the group consisting of strong ionic salts, anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, a solvent miscible with the comoosition, or mixtures thereof. isopropanol,

27. A composition as in claim 26, wherein the solvent is / ethanol, butoxyethanol or dipropvlene glycol methvlether.

28. A composition substantially as defined in any one of examples 1 to 54.

29. A method of forming a composition as claimed in any one of claims 1 to 28, comprising dissolving in water (a) at least one compound selected from the group consisting of acids and acidic salts (b) a thickening agent which is at least one of the compounds selected from the group consisting of compounds of the formula: OH ■* r» ^ •<-* j- -i_ 39 R 1 R '4 / R - N or compounds of the formula N ^ 0 \ 2 R '5 (I) (II) and each in which R/ R^ arejk substituted or an unsubstituted alicyl, arvl, alkaryl, aralkyl or alkenyl group, Rj_ is hydrogen, a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R2 is hydrogen, a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenvl croup, R, is a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, R^ is a substituted or unsubstituted alkyl, aryl, alkaryl, aralkyl or alkenyl group, or R^ and R2/ or R< and Rs when taken together comprise a substituted or unsubstituted heterocyclic ring, provided that if either R, R-, or R2 is an alkyl or alkenyl group derived from a fatty acid obtained from a natural oil or fat or an equivalent synthetic fatty acid, or is an alkaryl group containing from 8 to 12 carbon atoms in the alkyl moiety, then the other substituents are not respectively of the formulae: where A is either ethoxy or propoxv and X, Y are independently 1, 2 or 3, and optionally (c) a strong ionic salt, said thickening agent and the at least one compound selected from the group consisting of acids and acidic salts being together substantially water soluble, in amounts sufficient to produce a viscosity of not less than 30 centipoise at 25°C when measured with a Brookfield RVT viscometer at 50 rpm " spindle. - [A]x-3 and-[A]y-H -40-

30. A thickened aqueous composition as claimed in claim one, substantially as set out herein, with reference to any one of the examples.

31. A method as claimed in claim 29, substantially as sec out herein/ with reference to any one of the examples. </div>