(19)
(11) EP 0 793 707 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
29.01.2003 Bulletin 2003/05

(21) Application number: 95942503.4

(22) Date of filing: 14.11.1995
(51) International Patent Classification (IPC)7C11D 1/835, C11D 3/39
(86) International application number:
PCT/US9515/495
(87) International publication number:
WO 9601/7044 (06.06.1996 Gazette 1996/26)

(54)

THICKENED BLEACHING COMPOSITIONS, METHOD OF USE AND PROCESS FOR MAKING THEM

VERDICKTE BLEICHMITTELZUSAMMENSETZUNGEN, GEBRAUCHSVERFAHREN UND VERFAHREN ZU DEREN HERSTELLUNG

COMPOSITIONS DE BLANCHIMENT EPAISSIES, ET LEUR PROCEDE D'UTILISATION ET DE FABRICATION


(84) Designated Contracting States:
AT BE CH DE DK ES FR GB GR IE IT LI LU NL PT SE

(30) Priority: 25.11.1994 BE 9487018

(43) Date of publication of application:
10.09.1997 Bulletin 1997/37

(73) Proprietor: THE PROCTER & GAMBLE COMPANY
Cincinnati, Ohio 45202 (US)

(72) Inventors:
  • BIANCHETTI, Giulia, Ottavia
    I-00144 Roma (IT)
  • CARDOLA, Sergio
    I-00064 Roma (IT)
  • PACE, Luigi
    I-80067 Sorrento (IT)
  • BLYTH, Kevin, Graham
    Tyne and Wear NE26 1JQ (GB)
  • SHAW, Elizabeth, Ann
    Northumberland NE23 9FR (GB)

(74) Representative: Engisch, Gautier et al
Procter & Gamble European Technical Center N.V. Temselaan 100
1853 Strombeek-Bever
1853 Strombeek-Bever (BE)


(56) References cited: : 
EP-A- 0 188 025
EP-A- 0 275 043
EP-A- 0 598 694
EP-A- 0 621 335
EP-A- 0 265 979
EP-A- 0 404 293
EP-A- 0 601 792
US-A- 4 166 794
   
     
    Remarks:
    The file contains technical information submitted after the application was filed and not included in this specification
     
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    Technical field



    [0001] The present invention relates to aqueous bleaching compositions, more particularly to stable acidic thickened aqueous compositions comprising a source of persulfate salt. Said compositions find particular application in the cleaning of hard-surfaces, especially inclined hard-surfaces, such as toilet bowls and the like.

    Background



    [0002] A great variety of bleaching and cleaning compositions have been described in the art. Bleaching/cleaning compositions comprising a source of active oxygen and formulated at low pH are particularly interesting for the cleaning of hard-surfaces, especially for the hygienic cleaning of sanitary fittings such as toilet bowls and the like.

    [0003] Representative of this technical field is, for instance, EP-A-598 694 which discloses acidic aqueous compositions comprising persulfate salts which are preferably in the form of an emulsion of nonionic surfactants.

    [0004] However, such compositions have not been found satisfactory as regards their residence time on the surface to be cleaned in particular if the surface is wet. Indeed, it is desired to formulate compositions having greater residence time on non-horizontal surfaces such as inclined wall of a toilet bowl when applied thereto, allowing thereby that said compositions perform their cleaning action for longer periods of time. There are many such compositions known in the art that have the requisite viscosity characteristics. However, most of the thickeners known in the art, whilst allowing to effectively increase the viscosity of aqueous acidic compositions, do have some disadvantages in use. Indeed, thickeners like nonionic surfactants (nonyl phenol ethoxylates) or quaternary ammonium compounds have the disadvantage that they require to be used at high levels to achieve satisfactory viscosity, thus making them expensive to use. Also, some thickeners show significant instability in acidic medium, especially in acidic medium with hydrogen peroxide, or a source thereof, like monopersulfate. Indeed, some thickeners are easily oxidizable by sources of active oxygen, like monopersulfate, in aqueous acidic compositions, leading thereby to a loss of the total amount of active oxygen which would otherwise be available to perform bleaching action on the surface to be cleaned. In other words, some thickeners do not allow to formulate acidic aqueous compositions comprising a source of active oxygen with satisfactory chemical stability for long storage periods.

    [0005] It is thus an object of the present invention to formulate acidic aqueous compositions comprising a source of active oxygen having improved thickening properties.

    [0006] It is a further object of the present invention to formulate acidic aqueous compositions comprising a source of active oxygen with high thickening at low total thickening surfactant level.

    [0007] It is another object of the present invention to formulate thickened aqueous acidic compositions comprising a source of active oxygen which are chemically stable for long storage periods.

    [0008] It has now been found that the above mentioned objects could be met by formulating an acidic aqueous composition comprising a source of persulfate salt and, as the thickening system, a quaternary ammonium compound together with a short chain amine oxide (C6-C10). More particularly, it has unexpectedly been found that the addition of a small amount of a short chain amine oxide to a quaternary ammonium compound, as the thickening system, in an acidic aqueous composition comprising a source of persulfate salt allows to formulate highly thickened aqueous acidic compositions as compared to the use of only said quaternary ammonium compound, as the thickening system, i.e. a thickening system being free of any short chain amine oxide. Alternatively, the present invention allows to use low level of total thickening surfactant to achieve a given viscosity for an acidic aqueous composition comprising a source of persulfate salt. In other words, to obtain a desired thickening effect for a given acidic aqueous composition, a lower level of total thickening surfactants (quaternary ammonium compounds and short chain amine oxides) is sufficient in the present invention, as compared to the level of quaternary ammonium compound which would otherwise be required to obtain the same thickening effect when used alone, in absence of any short chain amine oxide. This thickening effect is even more noticeable in the preferred compositions of the present invention wherein said persulfate salt is a monopersulfate salt. Indeed, it has been found that said persulfate salt together with said quaternary ammonium compound act as a thickening system.

    [0009] It has further been found that the thickening system of the present invention exhibits good stability in acidic medium and in presence of strong oxidants like persulfate salt. Indeed, the decomposition of said persulfate salt, is reduced with the thickening system of the present invention as compared to other surfactant blends like for instance alkylethoxylated alcohols. In other words, persulfate salt in thickened aqueous acidic compositions of the present invention are chemically stable for longer periods of storage.

    [0010] An advantage of the present invention is that the stable thickened aqueous acidic compositions comprising a source of active oxygen according to the present invention are less sensitive to the presence of perfumes. Indeed, the thickening system of the present invention allows to formulate stable acidic aqueous compositions comprising a source of persulfate salt and still having high viscosity, despite the presence of perfumes, even at high levels. In fact, high levels of perfume are known to have a general tendency to significantly decrease composition viscosity by changing micellar aggregation.

    [0011] Another advantage of the present invention is that said stable thickened aqueous acidic compositions are efficient on various surfaces to clean various soils and stains. Additionally, said compositions when used to treat hard surfaces, especially toilet bowls, exhibit outstanding soil discoloration, soil solubilization and emulsification properties together with a germicidal action, this when used both neat or diluted.

    [0012] A further advantage is that the present invention allows to formulate compositions which are clear, as opposite to clouded, and thus well accepted from a consumer view point. Also the present invention allows to formulate compositions that are Newtonian. By "Newtonian" it is meant herein a composition which has the same viscosity within a very wide range of applied shear stresses.

    [0013] In the field of thickened aqueous acidic compositions the following patent applications are representative of the prior art.

    [0014] EP-A-275 043 discloses an acidic cleaner for aluminium surfaces containing a peroxide, acids, a C12-C22 alkyl dimethylamine oxide. Said cleaner has a pH at most 2. EP-A-275 043 discloses cationic surfactants as optional ingredients but no specific compounds of this class of surfactants are mentioned, let alone quaternary ammonium compounds.

    [0015] EP-A-265 979 discloses acidic thickened aqueous cleaning composition comprising a disinfecting and/or oxidizing agent, an organic anionic sulphonate and a surfactant selected from the group of (1) quaternary ammonium compounds wherein at least one of the hydrocarbon groups linked to the nitrogen is a linear or branched alkyl group containing at least 12 carbon atoms and of (2) tertiary amine oxides wherein at least one of the hydrocarbon groups linked to the nitrogen is a linear or branched alkyl group containing at least 16 carbon atoms, In contrast, the present invention uses quaternary ammonium compounds together with short chain amine oxides (C6-C10) as the thickening system. Also, nowhere in EP-A-265 979 a source of active oxygen is disclosed.

    [0016] EP-A-188 025 discloses aqueous stable thickened low-pH bleaching compositions comprising an inorganic peroxy compound, a strong acid and a thickening.; syrfactant. In EP-A-188 025 the thickening surfactant is selected from (1) amine oxides wherein at least one of the hydrocarbon groups linked to the nitrogen is a linear or branched alkyl group of C6 to C18 carbon atoms, preferably C12 to C18, (2) amines and (3) quaternary ammonium salts wherein at least one of the hydrocarbon groups linked to the nitrogen is a linear or branched alkyl group of C8 to C18 carbon atoms. Indeed, EP-A-188 025 teaches to use as a thickening surfactant one of these surfactants. And as regards the amine oxides, this patent application teaches to preferably use long chain amine oxides. Also none of the compositions exemplified comprises, as the thickening system, a quaternary ammonium compound together with an amine oxide, let alone a quaternary ammonium compound together with a short chain amine oxide.

    Summary of the invention



    [0017] The present invention encompasses a stable thickened aqueous acidic bleaching composition comprising a source of persulfate salt and, as a thickening system, a quaternary ammonium compound and an amine oxide according to the formula R1R2R3NO wherein R2 and R3 are independently C1-C4 alkyl groups and wherein R1 is a C6 to C10 alkyl group wherein said quaternary ammonium compound is a quaternary ammonium compound wherein one or two of the hydrocarbon groups linked to nitrogen are a linear or branched alkyl group of 6 to 30 carbon atoms, preferably of 10 to 25 carbon atoms and more preferably of 12 to 20 carbon atoms, saturated or unsaturated, and wherein the other hydrocarbon groups linked to the nitrogen are independently substituted or unsubstituted, linear or branched alkyl chain of from 1 to 4 carbon atoms, preferably of from 1 to 3 carbon atoms and more preferably are methyl groups and wherein the counterion used in said quaternary ammonium compound is preferably selected from the group of fluoride, or methyl sulfate, or methylsulfonate or hydroxide.

    [0018] In a preferred embodiment the stable thickened aqueous acidic compositions of the present invention further comprise a perfume.

    [0019] The present invention also encompasses a process of treating hard-surfaces wherein a stable thickened aqueous acidic composition, according to the present invention, is used.

    [0020] The present invention also encompasses a process for the manufacture of a composition according to the present invention wherein :
    • an acidic matrix is prepared which comprises at least water, a source of persulfate salt and an acid,
    • then a quaternary ammonium compound is added to said matrix,
    • then a perfume, if present, is further added and finally a short chain amine oxide is added,
    • the resulting composition is then stirred over at least three hours.


    [0021] The present invention further encompasses the use of persulfate salt together with a quaternary ammonium compound and an amine oxide having the formula R1R2R3NO wherein R2 and R3 are independently C1-C4 alkyl and wherein R1 is a C6-C10 alkyl group in an aqueous acidic composition to increase the viscosity of said composition, wherein said quaternary ammonium compound is a quaternary ammonium compound wherein one or two of the hydrocarbon groups linked to nitrogen are a linear or branched alkyl group of 6 to 30 carbon atoms, preferably of 10 to 25 carbon atoms and more preferably of 12 to 20 carbon atoms, saturated or unsaturated, and wherein the other hydrocarbon groups linked to the nitrogen are independently substituted or unsubstituted, linear or branched alkyl chain of from 1 to 4 carbon atoms, preferably of from 1 to 3 carbon atoms and more preferably are methyl groups and wherein the counterion used in said quaternary ammonium compound is preferably selected from the group of fluoride, or methyl sulfate, or methylsulfonate or hydroxide.

    [0022] The compositions according to the present invention comprise, as an essential element, a source of persulfate salts or mixtures thereof. The source of active oxygen according to the present invention acts as an oxidizing agent, it increases the ability of the compositions to remove colored stains and organic stains in general, to destroy malodorous molecules and to kill germs.

    [0023] Persulfate salts or mixtures thereof are the sources of active oxygen to be used in the compositions according to the present invention. Preferred persulfate salt to be used herein is the monopersulfate triple salt. One example of monopersulfate salt commercially available is potassium monopersutfate commercialized by Peroxide Chemie GMBH under the trade name Curox®. Other persulfate salts such as dipersulfate salts commercially available from Peroxide Chemie GMBH can be used in the compositions according to the present invention.

    [0024] The compositions according to the present invention comprise from 0.1% to 30% by weight of the total composition of said source of active oxygen, or mixtures thereof, preferably from 0.1% to 20%, and more preferably from 0.1% to 15%.

    [0025] Persulfate salts are used herein, as it has been found that they allow when used together with a quaternary ammonium compound and an amine oxide to increase the viscosity of an aqueous acidic composition. This is especially noticeable in said aqueous acidic compositions in absence of perfumes. Indeed, it has now been found that the addition of a persulfate salt such as a monopersulfate salt, as the source of active oxygen, to: an aqueous acidic composition comprising a quaternary ammonium compound such as C16 trimethyl ammonium methylsulfate improves the viscosity of said composition as compared to the viscosity of the same, composition but without said persulfate salt. It is believed that (HSO5-) anion coming from persulfate salt like monopersulfate salt strongly interacts with the cation head group of the quaternary ammonium compound displacing its own counterion (e.g., methylsialfate). It is believed that the interaction of persulfate salt like monopersulfate salt with a quaternary ammonium compound plays a significant role in thickening the compositions of the present invention, together with the thickening effect related to the addition of short chain amine oxide to said quaternary ammonium compound.

    [0026] Thus in another aspect, the present invention further encompasses the use of persulfate salt together with a quaternary ammonium compound and an amine oxide in an aqueous acidic composition to increase the viscosity of said composition.

    [0027] The compositions of the present invention comprise as a further essential element a thickening system. Said thickening system comprises a quaternary ammonium compound, or mixtures thereof, together with a short chain amine oxide, or mixtures thereof.

    [0028] Suitable quaternary ammonium compounds to be used according to the present invention are quaternary ammonium compounds wherein one or two of the hydrocarbori groups linked to nitrogen are a linear or branched alkyl group of 6 to 30 carbon atoms, preferably of 10 to 25 carbon atoms and more preferably 12 to 20 carbon atoms, saturated or unsaturated, and wherein- the other hydrocarbon groups (i.e. three when one hydrocarbon group is along chain hydrocarbon group as mentioned hereinbefore or two when two hydrocarbon groups are long chain hydrocarbon groups as mentioned hereinbefore) linked to the nitrogen are independently substituted or unsubstituted, linear or branched, alkyl chain of from 1 to 4 carbon atoms, preferably of from 1 to 3 carbon atoms and more preferably are methyl groups. In the embodiment of the present invention where persulfate salts or mixtures thereof are used as sources of active oxygen the quaternary ammonium compound is preferably a non-chloride quaternary ammonium compound. The counterion used in said quaternary ammonium compounds are compatible with any source of active oxygen and are selected from the group of fluoride or methyl sulfate, or methylsulfonate, or hydroxide and the like.

    [0029] Particularly preferred to be used in the compositions of the present invention are trimethyl quaternary ammonium compounds like myristyl trimethylsulfate, cetyl trimethylsulfate and/or tallow trimethylsulfate. Such trimethyl quaternary ammonium compounds are commercially available from Hoechst, or from Albright & Wilson under the trade name EMPIGEN CM®.

    [0030] The compositions according to the present invention comprise from 0.1% to 20% by weight of a quaternary ammonium compound, or mixtures thereof, preferably of from 0.1% to 15%, more preferably of from 0.1% to 10% and most preferably of from 1% to 5%.

    [0031] Suitable short chain amine oxides to be used according to the present invention are amine oxides having the following formula R1R2R3NO wherein R1 is a C6 to C10 alkyl group, preferably a C8 to C10 alkyl group and wherein R2 and R3 are independently substituted or unsubstituted, linear or branched alkyl groups of from 1 to 4 carbon atoms, preferably of from 1 to 3 carbon atoms and more preferably are methyl groups. R1 may be a linear or branched alkyl group, being saturated or unsaturated. Suitable short chain amine oxides for use herein are preferably compatible with any source of active oxygen. Preferred short chain amine oxides for use herein are for instance natural blend C8/C10 amine oxide available from Hoechst.

    [0032] The compositions according to the present invention comprise from 0.01 % to 15% by weight of a short chain amine oxide, or mixtures thereof, preferably of from 0.1% to 10% more preferably of from 0.1% to 5% and most preferably of from 0.1% to 3%.

    [0033] The total level of thickening system, i.e. of quaternary ammonium compound and of short chain amine oxide, to be used in a given aqueous acidic composition comprising a source of active oxygen depends on the thickening desired for said composition, said level being lower than 20%, preferably between 1% and 15%, more preferably between 1% and 10% and most preferably between 1% and 6%.

    [0034] The compositions of the present invention have a viscosity of more than 250 cps at 20°C, preferably of from 250 cps to 1500 cps and more preferably of from 250 cps to 900 cps, when measured with a Brookfield viscometer at 60 rpm with a spindle n° 2 or with the Carri-med rheometer at 50 dyne/cm2.

    [0035] Furthermore, the stable thickened aqueous acidic compositions of the present invention comprise a quaternary ammonium compound and a short chain amine oxide, as the thickening system, the weight ratio of said short chain amine oxide to said quaternary ammonium compound being from 1:2 to 1:100, preferably from 1:4 to 1:30 and more preferably from 1:10 to 1:20.

    [0036] In an embodiment of the present invention the compositions as described hereinbefore further comprise a perfume or mixtures thereof. It is well known that perfumes have a general tendency to significantly decrease the viscosity of compositions in which they are introduced. An advantage of the thickened acidic compositions of the present invention is, that they are less sensitive to the presence of perfume, even the presence of high levels of perfumes. Suitable perfumes to be used herein are all the perfumes well known in the field per se or blend of such perfumes.

    [0037] The compositions according to the present invention comprise up to 3% by weight of the total composition of a perfume or mixtures thereof, preferably of from 0.1% to 2% and more preferably of from 0.2% to 1%.

    [0038] The compositions of the present invention are acidic compositions. In order to obtain appropriate stability of the source of active oxygen in the compositions according to the present invention, said compositions are formulated at a pH between 0 to 6, more preferably at a pH between 0 and 4 and most preferably at a pH between 0 and 2. Acidity further contributes to formulate compositions according to the present invention which exhibit good limescale removing performance while having also good disinfecting properties. Accordingly, the compositions of the present invention further comprise organic and/or inorganic acids. Particularly suitable organic acids to be used herein are aryl and/or alkyl sulfonate, such as methane sulfonic acids, citric acid, succinic acid, sulphamic acid and the like. Particularly suitable inorganic acids are sulfuric, phosphoric, nitric acids and the like.

    [0039] The compositions according to the present invention are aqueous. The compositions according to the present invention comprise from 40% to 99% by weight of the total composition of water, preferably from 60% to 95%, most preferably from 70% to 90%. Deionized water is preferably used.

    [0040] As an optional but highly preferred ingredient the compositions according to the present invention further comprise an alkali metal sulphate or mixtures thereof. Preferred alkali metal sulphates to be used herein include potassium sulphate, sodium sulphate or mixtures thereof. We have now found that the addition of an alkali metal sulphate in the compositions of the present invention comprising persulfate salt such as monopersulfate salt, as the source of active oxygen, improves the chemical stability of said compositions. Indeed the percentage of monopersulfate lost upon storage time in a liquid composition according to the present invention comprising a given amount of monopersulfate and an alkali metal salt of sulphate is reduced as compared to the percentage of monopersulfate lost upon storage time in the same composition but without said alkali metal sulphate. Monopersulfate concentration can be measured as already defined herein before. It is believed that the addition of an alkali metal sulphate stabilises monopersulfate salts by shifting the following equilibrium to the left hand side:



    [0041] Accordingly the compositions according to the present invention comprise up to 10% by weight of the total composition of said alkali metal sulphate or mixtures thereof, preferably from 1% to 10% and more preferably from 2% to 7%.

    [0042] Depending on the end use envisioned, the compositions according to the present invention may further comprise a variety of other ingredients including other surfactants of all types to boost the performance over a wider range of soils/encrustations, organic or inorganic alkalis, dyes, optical brighteners, builders, chelants, pigments, enzymes, dye transfer inhibitors, solvents, buffering agents, stabilizers and the like.

    [0043] The present invention further encompasses a process of treating hard-surfaces, especially non-horizontal surfaces, wherein a composition according to the present invention is used in its neat or diluted form.

    [0044] By "in its diluted form" it is meant herein that said compositions may be diluted with water up to 99% of water. Said dilution may occur either before, after or while said composition is applied to a hard-surface.

    [0045] The compositions herein find a preferred application in the cleaning of toilet bowls and bath tubs. While cleaning toilet bowls compositions according to the present invention may be diluted while or after they are applied to the surface to be cleaned. For example, said compositions may be dispensed from a container onto said hard-surface, then diluted in water and left to act onto said surfaces, then removed by rinsing or flushing.

    [0046] As used in the foregoing paragraphs, the expression "treating" includes washing as the compositions used in the process according to the present invention comprise surfactants and bleaching agents as said compositions also comprise a source of active oxygen, preferably persulfate salts.

    [0047] The compositions according to the present invention may be manufactured by adding the different ingredients in any order. However, the desired initial viscosity of an aqueous composition of the present invention is obtained immediately, when following a preferred mixing order for the incorporation of the different ingredients in said composition. Accordingly, the present invention further encompasses a process for the manufacture of the compositions of the present invention, wherein said process comprises the steps of:
    • preparing an acidic matrix comprising at least water, a source of persulfate salt and an acid,
    • adding to said matrix the quaternary ammonium compound,
    • then adding the perfume if present and finally the short chain amine oxide,
    • and as a final step the resulting composition is stirred over at least three hours.


    [0048] The present invention is further illustrated by the following examples.

    Example I



    [0049] Compositions are made which comprise the listed ingredients in the listed proportions (weight %).
    Compositions #1 #2 #3 #4 #5
    C16 trimethyl ammonium methylsutfate 4.0 4.2 5.0 0.0 0.0
    C16/18 trimethyl ammonium methylsulfate 0.0 0.0 0.0 4.0 4.0
    C8/C10 amine oxide 0.2 0.0 0.0 0.2 0.0
    Curox® * 6.0 6.0 6.0 6.0 6.0
    Methane sulfonic acid 5.0 5.0 5.0 5.0 5.0
    Perfume 0.7 0.7 0.7 0.7 0.7
    Water and minors up to 100
    pH 1 1 1 1 1
    Initial viscosity** (cps) 300 20 300 960 30
    Appearance clear not clear clear clear not clear
    Rheological Behaviour Newt. Pseud. Newt. Pseud Newt.
    * Curox® is one of the commercial names of monopersulfate salts
    **Viscosity grows with time; therefore, those are the lowest achievable viscosities with the above indicated compositions.


    [0050] The initial viscosity of the above compositions were measured by a Carri-Med Rheomoter at fixed shear stress (50 dyne/cm2) at 20°C. It has been chosen a standard value of the shear stress to compare the viscosity of the above mentioned compositions, some of which showing a pseudoplastic behaviour. 50 dyne/cm2 as shear stress value is representative of a fluid flow occurring on a inclined surface when the product thickness is around 1mm and the only external force is due to the gravity field as per toilet cleaning application.

    [0051] Compositions #1 and #4 are representative of the stable thickened aqueous acidic compositions according to the present invention, i.e. they comprise a quaternary ammonium compound and a short chain amine oxide as the thickening system. Compositions #2, #3 and #5 are taken as reference, they are free of short chain amine oxides.

    [0052] The above data surprisingly show that the addition of a small amount of a short chain amine oxide (0.2% by weight) to a quaternary ammonium compound (4% by weight) in an acidic composition comprising a source of active oxygen, like monopersulfate, allows to formulate a composition having a higher viscosity as compared to the same composition wherein the thickening system used is only a quaternary ammonium compound. (See composition #1 with a viscosity of 300 cps versus composition #2 with a viscosity of 20 cps as well as composition #4 with a viscosity of 960 cps as compared to composition #5 with a viscosity of 30 cps).

    [0053] Also the above data show that the addition- of a small amount of short chain amine oxide (0.2% by weight) to quaternary ammonium compound (4% by weight) in an acidic composition comprising a source of active oxygen, like monopersulfate, allows to decrease the level of total thickening surfactant needed to formulate an aqueous acidic composition with a desired viscosity as compared to the use, as a thickening system, of a quaternary ammonium compound alone without any short chain amine oxide (see composition #1 with a level of 4.2% of thickening system according to the present invention versus composition #3 with a level of 5% of thickening system in order to obtain compositions having the same viscosity, i.e. 300 cps). In other words, the present invention allows to formulate thickened aqueous acidic compositions at low total level of thickening surfactants, i.e. to achieve the same viscosity, the thickening system of the present invention used in composition #1 allows a reduction of 16% by weight of the total level of thickening surfactant needed as compared to the level required with composition #3 .

    [0054] The data also show that the compositions according to the present invention were clear compositions, as opposite to clouded (i.e. not clear) compositions and Newtonian compositions.

    Example II



    [0055] Compositions are made which further illustrate the present invention and which comprise the listed ingredients in the listed proportions (weight %).
    Compositions #1 #2 #3 #4 #5
    C16 trimethyl ammonium methylsulfate 4.00 4.00 4.00 4.00 4.00
    C8/C10 amine oxide 0.00 0.00 0.30 0.30 0.30
    Curox® * 6.00 6.00 0.00 6.00 4.00
    Sulfuric acid 6.00 6.00 4.00 6.00 6.00
    Perfume 0.00 0.70 0.70 0.70 0.70
    Water and minors up to 100
    pH < 2 < 2 < 2 < 2 < 2
    Initial viscosity** (cps) 5000 < 50 50 300 250
    Appearance clear cloud clear clear clear
    Rheological Behaviour Newt. Pseud. Newt. Newt. Newt.
    * Curox® is one of the commercial names of monopersulfate salts
    ** Viscosity grows with time; therefore, those are the lowest achievable viscosities with the above indicated compositions.


    [0056] The initial viscosity of the above compositions were measured by a Carri-Med Rheomoter at fixed shear stress (50 dyne/cm2) at 20°C. It has been chosen a standard value of the shear stress to compare the viscosity of the above mentioned compositions, some of which showing a pseudoplastic behaviour. 50 dyne/cm2 as shear stress value is representative of a fluid flow occurring on a inclined surface when the product thickness is around 1mm and the only external force is due to the gravity field as per toilet cleaning application.

    [0057] Compositions #1 and #2 are taken as reference, they are free of short chain amine oxides. Composition #3 is taken as reference, it is free of monopersulfate salt. Compositions #4 and #5 are representative of the stable thickened aqueous acidic compositions according to the present invention, i.e. they comprise a quaternary ammonium compound, a short chain amine oxide and monopersulfate salt.

    [0058] The above data surprisingly show that the addition of a monopersulfate salt to a acidic aqueous composition comprising a short chain amine oxide and a quaternary ammonium compound allows to formulate a composition having a higher viscosity as compared to the same composition but without said monopersulfate salt. (See compositions #4 and #5 comprising respectively 6% and 4% by weight of the total composition of monopersulfate salt with a viscosity of respectively 300 cps and 250 cps as compared to composition #3 without monopersulfate salt and with a viscosity of 50 cps). Also the above data show the correlation between the increase of the concentration of monopersulfate salt and the increase of viscosity in said matrix.

    [0059] The above results further show that the present invention allows to formulate thickened aqueous acidic compositions at low total level of thickening surfactants, even if perfume is present, by combining monopersulfate, quaternary ammonium compound and short chain amine oxide.

    Example III



    [0060] Compositions are made which further illustrate the present invention and which comprise the listed ingredients in the listed proportions (weight %).
    Compositions #1 #2 #3 #4
    C16 trimethyl ammonium methylsulfate 4.70 5.00 5.70 7.00
    C8/C10 amine oxide 0.36 0.38 0.44 0.54
    Curox® * 6.00 6.00 6.00 6.00
    Methane sulfonic acid 5.00 5.00 5.00 5.00
    Perfume 0.7 0.7 0.7 0.7
    Sodium sulphate 5.00 5.00 5.00 5.00
    Water and minors up to 100 up to 100 up to 100 up to 100
    pH < 2 < 2 < 2 < 2
    Initial viscosity (cps) 370 400 800 1400
    Appearance clear clear clear clear
    Rheological Behaviour Newt. Newt. Newt. Newt.

    Example IV



    [0061] 
    Compositions #1 #2 #3 #4 #5 #6
    C16 trimethyl ammonium methylsulfate 4.00 4.00 4.00 4.00 4.00 4.00
    C8/C10 amine oxide 0.30 0.10 0.30 0.30 0.30 0.30
    Curox® * 6.00 6.00 6.00 6.00 6.00 6.00
    Methanesulfonic acid 10.00 15.00 0.00 0.00 5.00 0.00
    Sulfuric acid 0.00 0.00 3.00 6.00 6.00 0.00
    Phosphoric acid 0.00 0.00 0.00 0.00 0.00 12.00
    Perfume 0.70 0.70 0.70 0.70 0.70 0.70
    Water and minors up to 100
    pH 0.66 0.35 1.00 0.78 0.50 1.00
    Initial viscosity (cps) 270 330 380 400 300 320
    Appearance clear clear clear clear clear clear
    Rheological Behaviour Newt. Newt. Newt. Newt. Newt. Newt.
    * Curox® is one of the commercial names of monopersulfate salts.


    [0062] All the above mentioned acidic aqueous compositions comprising monopersulfate provide significant benefits in toilet soils cleaning both when used neat or diluted. Said compositions were found to be stable over long periods of time. Indeed, these compositions had not more than 10% loss after 1 month at room temperature.


    Claims

    1. A stable thickened aqueous acidic composition comprising a source of persulfate salt, a quaternary ammonium compound and an amine oxide having the following formula R1R2R3NO wherein R2 and R3 are independently C1-C4 alkyl groups and wherein R1 is a C6 to C10 alkyl group, wherein said quaternary ammonium compound is a quaternary ammonium compound wherein one or two of the hydrocarbon groups linked to nitrogen are a linear or branched alkyl group of 6 to 30 carbon atoms, preferably of 10 to 25 carbon atoms and more preferably of 12 to 20 carbon atoms, saturated or unsaturated, and wherein the other hydrocarbon groups linked to the nitrogen are independently substituted or unsubstituted, linear or branched alkyl chain of from 1 to 4 carbon atoms, preferably of from 1 to 3 carbon atoms and more preferably are methyl groups and wherein the counterion used in said quaternary ammonium compound is preferably selected from the group of fluoride, or methyl sulfate, or methylsulfonate or hydroxide.
     
    2. A composition according to any of the preceding claims wherein in said amine oxide having the formula R1R2R3NO, R1 is a C8 to C10 alkyl group, and R2 and R3 are independently alkyl groups of from 1 to 3 carbon atoms, and preferably are methyl groups.
     
    3. A composition according to any of the preceding claims wherein said composition comprises from 0.01% to 15% by weight of the total composition of said amine oxide, or mixtures thereof, preferably of from 0.1% to 10% and more preferably of from 0.1% to 5%.
     
    4. A composition according to any of the preceding claims wherein said composition comprises from 0.1% to 20% by weight of the total composition of said quaternary ammonium compound, or mixtures thereof, preferably of from 0.1% to 15% and more preferably of from 0.1 to 10%.
     
    5. A composition according to any of the preceding claims wherein in said composition the weight ratio of said amine oxide to said quaternary ammonium compounds is from 1:2 to 1:100, preferably from 1:4 to 1:30 and more preferably from 1:10 to 1:20.
     
    6. A composition according to any of the preceding claims wherein the total level of said quaternary ammonium compound and said amine oxide is no more than 20%, preferably between 1% to 15%, more preferably between 1 % to 10% and most preferably between 1% to 6%.
     
    7. A composition according to any of the preceding claims wherein said composition has a viscosity of more than 250 cps, preferably of from 250 cps to 1500 cps and more preferably of from 250 cps to 900 cps.
     
    8. A composition according to any of the preceding claims wherein the pH of said composition is from 0 to 6, preferably from 0 to 4 and more preferably from 0 to 2.
     
    9. A composition according to any of the preceding claims wherein said composition further comprises a perfume, preferably at a level of from 0% to 3% by weight of the total composition, more preferably at a level of from 0.1% to 2% and most preferably at a level of from 0.2% to 1%.
     
    10. A composition according to any of the preceding claims wherein said source of persulfate salt is preferably monopersulfate, and is present at a level of from 0.1% to 30% by weight of the total composition, preferably at a level of from 0.1% to 20% and more preferably at a level of from 0.1% to 15%.
     
    11. A composition according to any of the preceding claims wherein said composition further comprises an alkali metal sulphate, preferably potassium sulphate, sodium sulphate or mixtures thereof, in an amount up to 10% by weight of the total composition, preferably from 1% to 10% and more preferably from 2% to 7%.
     
    12. A process of treating hard-surfaces wherein a composition according to any of the preceding claims is used.
     
    13. A process for the manufacture of a composition according to any of claims 1 to 12 wherein in said process :

    - an acidic matrix is prepared which comprises at least said water, said source of persulfate salt and said acid,

    - then said quaternary ammonium compound is added to said matrix,

    - then said perfume, if present, is further added and finally said amine oxide is added,

    - the resulting composition is then stirred over at least three hours.


     
    14. The use of a persulfate salt together with a quaternary ammonium compound and an amine oxide having the formula R1R2R3NO wherein R2 and R3 are independently C1-C4 alkyl and wherein R1 is a C6-C10 alkyl group in an aqueous acidic composition to increase the viscosity of said composition, wherein said quaternary ammonium compound is a quaternary ammonium compound wherein one or two of the hydrocarbon groups linked to nitrogen are a linear or branched alkyl group of 6 to 30 carbon atoms, preferably of 10 to 25 carbon atoms and more preferably of 12 to 20 carbon atoms, saturated or unsaturated, and wherein the other hydrocarbon groups linked to the nitrogen are independently substituted or unsubstituted, linear or branched alkyl chain of from 1 to 4 carbon atoms, preferably of from 1 to 3 carbon atoms and more preferably are methyl groups and wherein the counterion used in said quaternary ammonium compound is preferably selected from the group of fluoride, or methyl sulfate, or methylsulfonate or hydroxide.
     


    Ansprüche

    1. Beständige, verdickte, wässrige, saure Zusammensetzung, umfassend eine Quelle für ein Persulfatsalz, eine quaternäre Ammoniumverbindung und ein Aminoxid der Formel R1R2R3NO, worin R2 und R3 unabhängig C1-C4-Alkylgruppen sind und R1 eine C6- bis C10-Alkylgruppe ist, wobei genannte quaternäre Ammoniumverbindung eine quaternäre Ammoniumverbindung ist, worin eine oder zwei der mit Stickstoff verknüpften Kohlenwasserstoffgruppen eine lineare oder verzweigte Alkylgruppe mit 6 bis 30 Kohlenstoffatomen, vorzugsweise 10 bis 25 Kohlenstoffatomen und am meisten bevorzugt 12 bis 20 Kohlenstoffatomen sind, gesättigt oder ungesättigt, und worin die anderen mit Stickstoff verknüpften Kohlenwasserstoffgruppen unabhängig substituierte oder unsubstituierte, lineare oder verzweigte Alkylketten von 1 bis 4 Kohlenstoffatomen, vorzugsweise 1 bis 3 Kohlenstoffatomen, und noch bevorzugter Methylgruppen sind, und worin das in genannter quaternärer Ammoniumverbindung verwendete Gegenion vorzugsweise ausgewählt ist aus der Gruppe, bestehend aus Fluorid oder Methylsulfat oder Methylsulfonat oder Hydroxid.
     
    2. Zusammensetzung nach vorangehendem Anspruch, worin im genannten Aminoxid der Formel R1R2R3NO R1 eine C8- bis C10-Alkylgruppe ist und R2 und R3 unabhängig Alkylgruppen mit 1 bis 3 Kohlenstoffatomen und vorzugsweise Methylgruppen sind.
     
    3. Zusammensetzung nach irgendeinem der vorhergehenden Ansprüche, worin genannte Zusammensetzung 0,01 bis 15 Gew.-% der Gesamtzusammensetzung an genanntem Aminoxid oder Mischungen davon, bevorzugt 0,1 bis 10%, und noch bevorzugter 0,1 bis 5% umfasst.
     
    4. Zusammensetzung nach irgendeinem der vorstehenden Ansprüche, worin genannte Zusammensetzung 0,1 bis 20 Gew.-% der Gesamtzusammensetzung an genannter quaternärer Ammoniumverbindung oder Mischungen davon, bevorzugt 0,1 bis 15%, und noch bevorzugter 0,1 bis 10% umfasst.
     
    5. Zusammensetzung nach irgendeinem der vorangehenden Ansprüche, worin In genannter Zusammensetzung das Gewichtsverhältnis von genanntem Aminoxid zu quaternärer Ammoniumverbindung von 1:2 bis 1:100, bevorzugt von 1:4 bis 1:30 und noch bevorzugter von 1:10 bis 1:20 reicht.
     
    6. Zusammensetzung nach irgendeinem der vorangehenden Ansprüche, worin die Gesamtmenge an genannter quaternärer Ammoniumverbindung und genanntem Aminoxid nicht mehr als 20%, vorzugsweise zwischen 1 und 15%, noch bevorzugter zwischen 1 und 10% und am meisten bevorzugt zwischen 1 und 6% beträgt.
     
    7. Zusammensetzung nach irgendeinem der vorangehenden Ansprüche, worin genannte Zusammensetzung eine Viskosität von mehr als 250 cps, bevorzugt 250 cps bis 1500 cps und noch bevorzugter 250 cps bis 900 cps aufweist.
     
    8. Zusammensetzung nach irgendeinem der vorangehenden Ansprüche, worin der pH genannter Zusammensetzung von 0 bis 6, vorzugsweise von 0 bis 4 und am meisten bevorzugt von 0 bis 2 reicht.
     
    9. Zusammensetzung nach irgendeinem der vorangehenden Ansprüche, worin genannte Zusammensetzung weiterhin ein Parfum umfasst, bevorzugt in einer Menge von 0 bis 3 Gew.-% der Gesamtzusammensetzung, noch bevorzugter in einer Menge von 0,1 bis 2% und am meisten bevorzugt in einer Menge von 0,2 bis 1%.
     
    10. Zusammensetzung nach irgendeinem der vorangehenden Ansprüche, worin genannte Quelle für ein Persulfatsalz vorzugsweise Monopersulfat ist und dies in einer Menge von 0,1 bis 30 Gew.-% der Gesamtzusammensetzung vorliegt, vorzugsweise in einer Menge von 0,1% bis 20% und weiter bevorzugt in einer Menge von 0,1 bis 15%.
     
    11. Zusammensetzung nach irgendeinem der vorangehenden Ansprüche, worin genannte Zusammensetzung weiterhin ein Alkalimetallsulfat umfasst, bevorzugt Kaliumsulfat, Natriumsulfat oder Mischungen davon, in einer Menge von bis zu 10 Gew.-% der Gesamtzusammensetzung, bevorzugt von 1 bis 10% und noch bevorzugter von 2 bis 7%.
     
    12. Verfahren zur Behandlung harter Oberflächen, worin eine Zusammensetzung nach irgendeinem der vorangehenden Ansprüche verwendet wird.
     
    13. Verfahren zur Herstellung einer Zusammensetzung nach irgendeinem der Ansprüche 1-12, worin in genanntem Verfahren:

    - eine saure Matrix bereitet wird, die mindestens genanntes Wasser, genannte Quelle an Persulfatsalz und genannte Säure umfasst,

    - anschließend genannte Ammoniumverbindung zur genannten Matrix zugegeben wird,

    - anschließend weiter genanntes Parfum, falls vorliegend, zugegeben und schließlich genanntes Aminoxid zugegeben wird,

    - die erhaltene Zusammensetzung dann mindestens drei Stunden lang gerührt wird.


     
    14. Verwendung eines Persulfatsalzes, zusammen mit einer quaternären Ammoniumverbindung und einem Aminoxid der Formel R1R2R3NO, worin R2 und R3 unabhängig C1-C4-Alkylgruppen sind und R1 eine C6-C10-Alkylgruppe ist, in einer wässrigen, sauren Zusammensetzung, um die Viskosität genannter Zusammensetzung zu erhöhen, worin genannte quaternäre Ammoniumverbindung eine quaternäre Ammoniumverbindung ist, worin eine oder zwei der mit Stickstoff verknüpften Kohlenwasserstoffgruppen eine lineare oder verzweigte Alkylgruppe mit 6 bis 30 Kohlenstoffatomen, vorzugsweise 10 bis 25 Kohlenstoffatomen und am meisten bevorzugt 12 bis 20 Kohlenstoffatomen sind, gesättigt oder ungesättigt, und worin die anderen mit Stickstoff verknüpften Kohlenwasserstoffgruppen unabhängig substituierte oder unsubstituierte, lineare oder verzweigte Alkylketten von 1 bis 4 Kohlenstoffatomen, vorzugsweise 1 bis 3 Kohlenstoffatomen und noch bevorzugter Methylgruppen sind, und worin das in genannter quaternären Ammoniumverbindung verwendete Gegenion vorzugsweise ausgewählt ist aus der Gruppe, bestehend aus Fluorid oder Methylsulfat oder Methylsulfonat oder Hydroxid.
     


    Revendications

    1. Composition acide aqueuse épaissie stable comprenant une source de sel de persulfate, un composé d'ammonium quaternaire et un oxyde d'amine ayant la formule suivante R1R2R3NO, où R2 et R3 sont indépendamment des groupes alkyle en C1-C4 et dans laquelle R1 est un groupe alkyle en C6-C10, dans laquelle ledit composé d'ammonium quaternaire est un composé d'ammonium quaternaire dans lequel un ou deux des groupes hydrocarbonés liés à l'azote est ou sont un groupe alkyle linéaire ou ramifié de 6 à 30 atomes de carbones, de préférence de 10 à 25 atomes de carbone, plus préférablement de 12 à 20 atomes de carbone, saturé ou insaturé, et dans lequel les autres groupes hydrocarbonés liés à l'azote sont des chaînes alkyle indépendamment substituées ou non substituées, linéaires ou ramifiées, de 1 à 4 atomes de carbone, de préférence de 1 à 3 atomes de carbone, plus préférablement des groupes méthyle, et dans laquelle le contre-ion utilisé dans ledit composé d'ammonium quaternaire est de préférence choisi dans le groupe d'un fluorure, d'un sulfate de méthyle ou d'un sulfonate de méthyle ou d'un hydroxyde.
     
    2. Composition selon l'une quelconque des revendications précédentes, dans laquelle, dans ledit oxyde d'amine ayant la formule R1R2R3NO, R1 est un groupe alkyle en C8-C10, et R2 et R3 sont indépendamment des groupes alkyle de 1 à 3 atomes de carbone, de préférence des groupes méthyle.
     
    3. Composition selon l'une quelconque des revendications précédentes, dans laquelle ladite composition comprend 0,01% à 15% en poids de la composition totale dudit oxyde d'aminé ou de leurs mélanges, de préférence 0,1% à 10%, plus préférablement 0,1% à 5%.
     
    4. Composition selon l'une quelconque des revendications précédentes, dans laquelle ladite composition comprend 0,1% à 20% en poids de la composition totale dudit composé d'ammonium quaternaire ou d'un de ses mélanges, de préférence 0,1% à 15%, plus préférablement 0,1% à 10%.
     
    5. Composition selon l'une quelconque des revendications précédentes, dans laquelle, dans ladite composition, le rapport pondéral dudit oxyde d'amine auxdits composés d'ammonium quaternaires est de 1:2 à 1:100, de préférence de 1:4 à 1:30, plus préférablement de 1:10 à 1:20.
     
    6. Composition selon l'une quelconque des revendications précédentes, dans laquelle la concentration totale dudit composé d'ammonium quaternaire et dudit oxyde d'amine n'est pas supérieure à 20%, de préférence comprise entre 1% et 15%, plus préférablement entre 1 et 10%, et le plus préférablement entre 1% et 6%.
     
    7. Composition selon l'une quelconque des revendications précédentes, dans laquelle ladite composition a une viscosité supérieure à 250 cps, et de préférence de 250 cps à 1500 cps, et plus préférablement de 250 cps à 900 cps.
     
    8. Composition selon l'une quelconque des revendications précédentes, dans laquelle le pH de ladite composition est de 0 à 6, de préférence de 0 à 4, et plus préférablement de 0 à 2.
     
    9. Composition selon l'une quelconque des revendications précédentes, dans laquelle ladite composition comprend en outre un parfum, de préférence à un taux de 0% à 3% en poids de la composition totale, plus préférablement à un taux de 0,1% à 2%, et le plus préférablement à un taux de 0,2% à 1%.
     
    10. Composition selon l'une quelconque des revendications précédentes, dans laquelle ladite source de sel de persulfate est de préférence un monopersulfate et est présente à un taux de 0,1% à 30% en poids de la composition totale, de préférence à un taux de 0,1% à 20%, et le plus préférablement à un taux de 0,1% à 15%.
     
    11. Composition selon l'une quelconque des revendications précédentes, dans laquelle ladite composition comprend en outre un sulfate de métal alcalin, de préférence le sulfate de potassium, le sulfate de sodium ou leurs mélanges, en quantité allant jusqu'à 10% en poids de la composition totale, de préférence de 1% à 10%, et plus préférablement de 2% à 7%.
     
    12. Procédé de traitement de surfaces dures, dans lequel on utilise une composition selon l'une quelconque des revendications précédentes.
     
    13. Procédé de fabrication d'une composition selon l'une quelconque des revendications 1 à 11, dans lequel, dans ledit procédé :

    - on prépare une matrice acide qui comprend au moins ladite eau, ladite source de sel de persulfate et ledit acide,

    - ensuite, ledit composé d'ammonium quaternaire est ajouté à ladite matrice,

    - puis, on ajoute encore ledit parfum, s'il y en a, et enfin on ajoute ledit oxyde d'amine,

    - la composition obtenue est ensuite agitée sur une période d'au moins trois heures.


     
    14. Utilisation d'un sel de persulfate conjointement avec un composé d'ammonium quaternaire et un oxyde d'amine ayant pour formule R1R2R3NO, dans laquelle R2 et R3 sont indépendamment un groupe alkyle en C1-C4 et dans laquelle R1 est un groupe alkyle en C6-C10, dans une composition acide aqueuse pour augmenter la viscosité de ladite composition, dans laquelle ledit composé d'ammonium quaternaire est un composé d'ammonium quaternaire dans lequel un ou deux des groupes hydrocarbonés liés à l'azote est ou sont un groupe alkyle linéaire ou ramifié de 6 à 30 atomes de carbone, de préférence de 10 à 25 atomes de carbone, et plus préférablement de 12 à 20 atomes, saturé ou insaturé, et dans laquelle les autres groupes hydrocarbonés liés à l'azote sont des chaînes alkyle indépendamment substituées ou non substituées, linéaires ou ramifiées, de 1 à 4 atomes de carbone, de préférence de 1 à 3 atomes de carbone, et plus préférablement des groupes méthyle, et dans laquelle le contre-ion utilisé dans ledit composé d'ammonium quaternaire est de préférence choisi dans le groupe d'un fluorure, d'un sulfate de méthyle, d'un sulfonate de méthyle ou d'un hydroxyde.