Patent Application
20100016205
This application claims benefit under 35 U.S.C. 119(a) of German patent application 10 2008 040486.1, filed on 17 Jul. 2008.
Any foregoing applications, including German patent application DE 10 2008 040486.1, and all documents cited therein or during their prosecution (“application cited documents”) and all documents cited or referenced in the application cited documents, and all documents cited or referenced herein (“herein cited documents”), and all documents cited or referenced in herein cited documents, together with any manufacturer's instructions, descriptions, product specifications, and product sheets for any products mentioned herein or in any document incorporated by reference herein, are hereby incorporated herein by reference, and may be employed in the practice of the invention.
The invention relates to the use of ionic liquids as an additive for cleaning processes in liquefied and/or supercritical gas according to the preamble of claim 1, especially in liquid and/or supercritical carbon dioxide.
Cleaning processes in liquid and/or supercritical gases can be used to free different articles of extraneous substances. The gases used are, for example, carbon dioxide, helium, argon, xenon, krypton, nitrogen oxides such as dinitrogen monoxide, hydrocarbons such as methane, ethane, propane, butane, pentane, ethylene, propylene, halogenated hydrocarbons and halogen-sulphur compounds such as sulphur hexafluoride. Particularly advanced processes are those for cleaning textiles, yarns, leather and comparable materials and surfaces with liquid or supercritical CO2, as described, for example, in DE 101 11 427. The process is notable particularly for eco-friendliness and the material-conserving cleaning method. For effective cleaning, the addition of detergents is necessary. Important detergent classes, for example, perfluoroalkylpoly(ethylene oxide) copolymers, AO-VAc (sodium bis(vinyl acetate)-8-sulphosuccinate) or AOK (sodium bis(5,5-dimethyl-4-oxohexyloxocarbonyl)-sulphosuccinate) are described in U.S. Pat. No. 5,783,082 and in Eastoe et al. Langmuir 2006, 22, 9832. The purpose of the detergents is the emulsification/dispersion of impurities in the solvent, such that they are effectively transported away with the solvent stream.
These known detergents each have different disadvantages. More particularly, they all exhibit weaknesses in the removal of hydrophilic, polar stains, for example of sweat stains. This weakness also limits the process in relation to the substrates to be cleaned. Hydrophilic substances, for example cotton, can be freed of soiling only with significant restrictions.
Generally, it can be stated that it is impossible to stabilize sufficient amounts of water in the compressed gas phase. It is therefore desirable to provide substances which form inverse micelles in compressed gas phases, especially in liquid CO2, and possess hydrophilic character.
It was therefore an object of the present invention to provide alternative detergents which are suitable, as detergents, for promoting or for improving the cleaning of articles to remove hydrophilic and/or polar impurities in compressed gas phases, especially when the compressed gas phase used is liquid or supercritical CO2.
It has been found that, surprisingly, this object can be achieved by using one or more ionic liquids as detergents. The present invention therefore provides cleaning compositions comprising a compressed gas and at least one detergent, which are characterized in that at least one detergent is an ionic liquid.
The present invention likewise provides a process for cleaning articles, in which the articles are contacted with a cleaning composition comprising a compressed gas and at least one detergent, characterized in that an inventive cleaning composition is used.
The inventive use of at least one ionic liquid as a detergent has the advantage that it forms inverse micelles in compressed gas phases, especially in liquid or supercritical CO2, which have polar character and absorb water or hydrophilic and/or polar impurities from surfaces and can be transported away with the solvent stream. It is thus possible for the first time to use a detergent which allows the cleaning of surfaces contaminated with hydrophilic, polar substances in compressed gases, especially liquid or supercritical CO2.
The inventive use of at least one ionic liquid as a detergent has, more particularly, the advantage that the cleaning of hydrophilic textiles, for example cotton, in compressed gases, especially in liquid or supercritical CO2, is also possible.
By virtue of a suitable selection of one or more ionic liquids, a tailored detergent can be provided, which satisfies the requirements with regard to the aforementioned properties.
The inventive use of ionic liquids in cleaning compositions also has the advantage of a process simplification, since complicated aqueous preliminary cleaning and subsequent drying of the articles to be cleaned can be dispensed with.
In addition, in the case of the inventive use of cleaning compositions comprising ionic liquids, they may comprise additives which nourish, protect or modify the articles to be cleaned, and can also be introduced by the cleaning process or can be applied to the articles during the cleaning process.
A further particular advantage of the inventive use of ionic liquids in cleaning compositions is that the ionic liquid used as a detergent can be removed completely from the compressed gas in a simple manner, by distilling the compressed gas and any further distillable substances out of the used cleaning composition. This is possible because ionic liquids have no measurable vapour pressure and other substances can thus be removed very easily by distillation.
The inventive cleaning compositions and the use thereof will be described by way of example hereinafter, without any intention that the invention be restricted to these illustrative embodiments. Where ranges, general formulae or compound classes are specified below, these shall encompass not just the corresponding ranges or groups of compounds which are mentioned explicitly but also all sub-ranges and sub-groups of compounds which can be obtained by selecting individual values (ranges) or compounds. When documents are cited within the present description, their content shall be incorporated fully into the disclosure content of the present invention.
The inventive cleaning composition comprising a compressed gas and at least one detergent is characterized in that at least one detergent is an ionic liquid. The inventive cleaning composition preferably consists exclusively of one or more ionic liquids and one or more compressed gases.
The ionic liquids present in the cleaning composition may be all known ionic liquids. Reviews of ionic liquids, their preparation and their properties can be found, for example, in “Ionic Liquids in Synthesis”, P. Wasserscheid, T. Welton (eds.), Wiley, in “Green Industrial Applications of Ionic Liquids”, NATO Science Series. Li. Mathematics, Physics and Chemistry, 92, or in “Ionic Liquids: Industrial Applications for Green Chemistry”, Robin D. Rogers (ed.), Acs. Symposium Series, 818.
The inventive cleaning composition may comprise, as a detergent, not just one ionic liquid, but rather it may also comprise a mixture of ionic liquids.
The compressed gas is preferably present as a liquid or supercritical phase in the inventive cleaning composition. The inventive composition preferably comprises, as the compressed gas, carbon dioxide, helium, argon, xenon, krypton, a nitrogen oxide, preferably dinitrogen monoxide, a hydrocarbon, preferably methane, ethane, propane, butane, pentane, ethylene or propylene, a halogenated hydrocarbon or a halogen-sulphur compound, preferably sulphur hexafluoride. The compressed gas in the inventive composition is more preferably carbon dioxide, especially liquid or supercritical carbon dioxide.
In the inventive composition, the mass ratio of compressed gas to ionic liquids is preferably 1 000 000:1 to 1:1, preferably 100 000:1 to 10:1, more preferably 10 000:1 to 100:1 and most preferably 5000:1 to 500:1.
The inventive cleaning composition preferably comprises, as an ionic liquid, at least one salt of the formula (I)
[A]n+[Y]n− (I)
in which
n is 1, 2, 3 or 4,
[A]+ is a quaternary ammonium cation, an oxonium cation, a sulphonium cation or a phosphonium cation (where these cations may in each case be substituted or unsubstituted) and
[Y]n− is a monovalent, divalent, trivalent or tetra-valent anion, or a mixed salt of the general formulae (IIa) to (IIc)
[A1]+[A2]+ [Y]2− (IIa),
[A1]+[A2]+[A3]+ [Y]3− (IIb) or
[A1]+[A2]+[A3]+[A4]+ [Y]4− (IIc)
where
[A1]+, [A2]+, [A3]+ and [A4]+ are selected independently from the groups specified for [A]+ and
[Y]2− to [Y]4− are each as defined for [Y]n− in formula (I), or
a mixed salt of the general formulae (IIIa) to (IIIj)
[A1]+[A2]+[A3]+[M1]+ [Y]4− (IIIa),
[A1]+[A2]+[M1]+[M2]+[Y]4− (IIIb),
[A1]+[M1]+[M2]+[M3]+[Y]4− (IIIc),
[A1]+[A2]+[M1]+[Y]3− (IIId),
[A1]+[M1]+[M2]+[Y]3− (IIIe),
[A1]+[M1]+[Y]2− (IIIf),
[A1]+[A2]+[M4]2+[Y]4− (IIIg),
[A1]+[M1]+[M4]2+[Y]4− (IIIh),
[A1]+[M5]3+[Y]4− (IIII) or
[A1]+[M4]2+[Y]3− (IIIj)
where
[A1]+, [A2]+ and [A3]+ are selected independently from the groups specified for [A]+,
[Y]2− to [Y]4− are each as defined for [Y]n− in formula I, and
[M1]+, [M2]+, [M3]+ are monovalent metal cations,
[M4]2+ are divalent metal cations and
[M5]3+ are trivalent metal cations,
or a mixture of a plurality of salts of the formulae I to IIIj.
Preferred ionic liquids have, as cations, substituted or unsubstituted, preferably substituted, ammonium, phosphonium, pyridinium or imidazolium cations.
The ionic liquids which are used with preference in accordance with the invention preferably comprise at least one cation of the general formulae:
R1R2R3R4N+ (IV)
R1R2N+=CR3R4 (V)
R1R2R3R4P+ (VI)
R1R2P+=CR3R4 (VII)
R1R2R3S+ (VIII)
in which
R1, R2, R3, R4 are the same or different and are each hydrogen, a linear or branched aliphatic hydrocarbon radical which has 1 to 30 carbon atoms and may contain double bonds, a cycloaliphatic hydrocarbon radical which has 5 to 40 carbon atoms and may contain double bonds, an aromatic hydrocarbon radical having 6 to 40 carbon atoms, an alkylaryl radical having 7 to 40 carbon atoms, a linear or branched aliphatic hydrocarbon radical which has 2 to 30 carbon atoms and is interrupted by one or more heteroatoms (oxygen, NH, NR′ where R′ is a C1-C30-alkyl radical which may contain double bonds, especially —CH3) and may contain double bonds, a linear or branched aliphatic hydrocarbon radical which has 2 to 30 carbon atoms and is interrupted by or more functions selected from the group of —O—C(O)—, —(O)C—O—, —NH—C(O)—, —(O)C—NH, —(CH3)N—C(O)—, —(O)C—N(CH3)—, —S(O2) —O—, —O—S(O2)—, —S(O2)—NH—, —NH—S(O2)—, —S(O2)—N (CH3)—, —N(CH3) —S(O)—, and may contain double bonds, a terminally OH—, OR′—, NH2—, N(H)R′—, N(R′)2-functionalized (where R′ is a C1-C30-alkyl radical which may contain double bonds), linear or branched, aliphatic or cycloaliphatic hydrocarbon radical which has 1 to 30 carbon atoms and may contain double bonds or a polyether with blockwise or random structure of the formula —(R5—O)n-R6, where
R5 is a linear or branched hydrocarbon radical containing 2 to 4 carbon atoms,
n is 1 to 100, preferably 2 to 60, and
R6 is hydrogen, a linear or branched aliphatic hydrocarbon radical which has 1 to 30 carbon atoms and may contain double bonds, a cycloaliphatic hydrocarbon radical which has 5 to 40 carbon atoms and may contain double bonds, an aromatic hydrocarbon radical having 6 to 40 carbon atoms, an alkylaryl radical or arylalkyl radical having 7 to 40 carbon atoms or a —C(O)—R7 radical where
R7 is a linear or branched aliphatic hydrocarbon radical which has 1 to 30 carbon atoms and may contain double bonds, a cycloaliphatic hydrocarbon radical which has 5 to 40 carbon atoms and may contain double bonds, an aromatic hydrocarbon radical having 6 to 40 carbon atoms, an alkylaryl radical or arylalkyl radical having 7 to 40 carbon atoms.
As cations, the ionic liquid may likewise contain those derived from saturated or unsaturated cyclic compounds or from aromatic compounds having in each case at least one trivalent nitrogen atom in a 4- to 10-membered, preferably 5- or 6-membered, heterocyclic ring which may optionally be substituted. Such cations can be described in simplified form (i.e. without indication of the exact position and number of the double bonds in the molecule) by the general formulae (IX), (X) and (XI) below, where the heterocyclic rings may also contain a plurality of heteroatoms:
where
R1 and R2 are each as defined above,
R may be a hydrogen, a linear or branched aliphatic hydrocarbon radical which has 1 to 30 carbon atoms and may contain double bonds, a cycloaliphatic hydrocarbon radical which has 5 to 40 carbon atoms and may contain double bonds, an aromatic hydrocarbon radical having 6 to 40 carbon atoms or an alkylaryl radical or arylalkyl radical having 7 to 40 carbon atoms.
X may be an oxygen atom, a sulphur atom or a substituted nitrogen atom (X=O, S, NR1).
Examples of cyclic nitrogen compounds of the aforementioned type are pyrrolidine, dihydropyrrole, pyrrole, imidazoline, oxazoline, oxazole, thiazoline, thiazole, isoxazole, isothiazole, indole, carbazole, piperidine, pyridine, the isomeric picolines and lutidines, quinoline and isoquinoline. The cyclic nitrogen compounds of the general formulae (IX), (X) and (XI) may be unsubstituted (R=H) or monosubstituted or polysubstituted by the R radical, and, in the case of polysubstitution by R, the individual R radicals may be different.
As cations, the ionic liquid may also contain those ions derived from saturated acyclic, saturated or unsaturated cyclic compounds or from aromatic compounds having in each case more than one trivalent nitrogen atom in a 4- to 10-membered, preferably 5- or 6-membered, heterocyclic ring. These compounds may be substituted both on the carbon atoms and on the nitrogen atoms. They may also be fused with unsubstituted or substituted benzene rings and/or cyclohexane rings to form polycyclic structures. Examples of such compounds are pyrazole, 3,5-dimethylpyrazole, imidazole, benzimidazole, N-methylimidazole, dihydropyrazole, pyrazolidine, pyridazine, pyrimidine, pyrazine, 2,3-, 2,5- and 2,6-dimethylpyrazine, cinnoline, quinoline, phthalazine, quinazoline, phenazine and piperazine. Especially cations derived from imidazole and its alkyl and phenyl derivatives have been found to be useful as constituents of ionic liquids.
As cations, the ionic liquid may likewise contain cations which contain two nitrogen atoms and are represented by the general formula (XII)
in which
R8, R9, R10, R11, R12 are the same or different and are each hydrogen, a linear or branched aliphatic hydrocarbon radical which has 1 to 30 carbon atoms and may contain double bonds, a cycloaliphatic hydrocarbon radical which has 5 to 40 carbon atoms and may contain double bonds, an aromatic hydrocarbon radical having 6 to 40 carbon atoms, an alkylaryl radical or arylalkyl radical having 7 to 40 carbon atoms, a linear or branched aliphatic hydrocarbon radical which has 1 to 30 carbon atoms and is interrupted by one or more heteroatoms (oxygen, NH, NR′ where R′ is a C1-C30-alkyl radical which may contain double bonds) and may contain double bonds, a linear or branched aliphatic hydrocarbon radical which has 1 to 30 carbon atoms and is interrupted by one or more functions selected from the group of —O—C(O)—, —(O)C—O—, —NH—C(O)—, —(O)C—NH, —(CH3)N—C(O)—, —(O)C—N(CH3)—, —S(O)—O—, —O—S(O)—S(O2)—NH—, —NH—S(O2)—, —S(O2)—N(CH3)—, —N(CH3)—S(O2)—, and may contain double bonds, a terminally OH—, OR′—, NH2—, N(H)R′—, N(R′)2-functionalized (where R′ is a C1-C30-alkyl radical which may contain double bonds), linear or branched, aliphatic or cycloaliphatic hydrocarbon radical which has 1 to 30 carbon atoms and may contain double bonds or a polyether with blockwise or random structure of the formula —(R5—O)n-R6,
where
R5 is a hydrocarbon radical containing 2 to 4 carbon atoms,
n is 1 to 100 and
R6 is hydrogen, a linear or branched aliphatic hydrocarbon radical which has 1 to 30 carbon atoms and may contain double bonds, a cycloaliphatic hydrocarbon radical which has 5 to 40 carbon atoms and may contain double bonds, an aromatic hydrocarbon radical having 6 to 40 carbon atoms, an alkylaryl radical having 7 to 40 carbon atoms or a —C(O)—R7 radical where
R7 is a linear or branched aliphatic hydrocarbon radical which has 1 to 30 carbon atoms and may contain double bonds, a cycloaliphatic hydrocarbon radical which has 5 to 40 carbon atoms and may contain double bonds, an aromatic hydrocarbon radical having 6 to 40 carbon atoms, an alkylaryl radical having 7 to 40 carbon atoms.
As cations of the formula (XII), the ionic liquids more preferably contain imidazolium ions selected from 1-methylimidazolium, 1-ethylimidazolium, 1- (1-butyl)-imidazolium, 1-(1-octyl)imidazolium, 1-(1-dodecyl)-imidazolium, 1-(1-tetradecyl)imidazolium, 1-(1-hexadecyl)-imidazolium, 1,3-dimethylimidazolium, 1-ethyl-3-methyl-imidazolium, 1-(1-butyl)-3-methylimidazolium, 1-(1-butyl)-3-ethylimidazolium, 1-(1-hexyl)-3-methylimidazolium, 1-(1-hexyl)-3-ethylimidazolium, 1-(1-hexyl)-3-butylimidazolium, 1-(1-octyl)-3-methylimidazolium, 1-(1-octyl)-3-ethylimidazolium, 1-(1-octyl)-3-butylimidazolium, 1-(l-dodecyl)-3-methylimidazolium, 1-(1-dodecyl)-3-ethylimidazolium, 1-(1-dodecyl)-3-butylimidazolium, 1-(1-dodecyl)-3-octylimidazolium, 1-(1-tetradecyl)-3-methylimidazolium, 1-(1-tetradecyl)-3-ethylimidazolium, 1-(1-tetradecyl)-3-butylimidazolium, 1-(1-tetradecyl)-3-octylimidazolium, 1-(1-hexadecyl)-3-methylimidazolium, 1-(1-hexadecyl)-3-ethylimidazolium, 1-(1-hexadecyl)-3-butylimidazolium, 1-(1-hexadecyl)-3-octylimidazolium, 1,2-dimethylimidazolium, 1,2,3-trimethylimidazolium, 1-ethyl-2,3-dimethylimidazolium, 1-(1-butyl)-2,3-dimethylimidazolium, 1-(1-hexyl)-2,3-dimethylimidazolium, 1-(1-octyl)-2,3-dimethylimidazolium, 1,4-dimethylimidazolium, 1,3,4-trimethylimidazolium, 1,4-dimethyl-3-ethylimidazolium, 3-butylimidazolium, 1,4-dimethyl-3-octylimidazolium, 1,4,5-trimethylimidazolium, 1,3,4,5-tetramethylimidazolium, 1,4,5-trimethyl-3-ethyl-imidazolium, 1,4,5-trimethyl-3-butylimidazolium and 1,4,5-trimethyl-3-octylimidazolium.
As cations, the ionic liquid may likewise contain ions which, in particular, form dications, trications or polycations from the aforementioned cations as a result of dimerization, trimerization or polymerization. The cations, especially dications, trications and polycations, may also be those which have a polymeric backbone, for example one based on siloxanes, polyethers, polyesters, polyamides or polyacrylates, in particular branched and hyperbranched polymers.
Preference is given to using quaternary ammonium salts of alkoxylated fatty acids—also known as alkanolamine ester quats—characterized by the generic formula of the R1R2R3R4N+A−(IV) type, in which R1 is an alkyl radical having 1 to 20 carbon atoms, R2 is an alkyl radical having 1 to 4 carbon atoms, R3 is a (CH2CHRO)n—H radical where n is 1 to 200 and R is H or CH3, R4 is an alkyl radical having 1 to 4 carbon atoms or a (CH2CHRO)n—H radical where n is 1 to 200, and R is H or CH3, and A− is a monovalent anion.
Among these compounds, substances of the formula
(i) R64-mN+[(CH2)n-Q-R7]mX−
are preferred, where
each R6 radical is independently an alkyl group or hydroxyalkyl group having 1 to 6 carbon atoms, or a benzyl group and preferably a methyl group,
R7 is independently hydrogen, a linear or branched alkyl group having 11 to 22 carbon atoms, a linear or branched alkenyl group having 11 to 22 carbon atoms, with the condition that at least one R7 radical is not hydrogen,
Q is independently selected from the groups of the formulae —O—C(O)—, —C(O)O, —NR8—C(O)—, —C(O)—NR8—, —O—C(O)—O, —CHR9—O—C(O)—or —CH(OCOR7)—CH2—O—C(O)—, where
R8 is hydrogen or a methyl, ethyl, propyl or butyl radical and R9 is hydrogen or methyl and Q is preferably —O—C(O)— or —NH—C(O)—;
m is 1 to 4 and preferably 2 or 3;
n is 1 to 4 and preferably 2;
X is an anion compatible with the application, for example methylsulphate, ethylsulphate, methylsulphonate, butylsulphate, octylsulphate, phosphinate or 2-(2-methoxyethoxy)ethylsulphate, preferably methylsulphate, 2-(2-methoxyethoxy)ethylsulphate, octylsulphate and phosphinate.
The quaternary ammonium compound may comprise mixtures of the compounds with different R7 groups which are not hydrogen, whose value ranges from 1 up to m. Preferably, such mixtures comprise an average of 1.2 to 2.5 R7 groups which are not hydrogen. The proportion of the non-hydrogen R7 groups is preferably 1.4 to 2.0 and preferentially 1.6 to 1.9.
The preferred quaternary ammonium compounds are the compounds of the type:
(ii) R6N+[CH2CHR9OH—] [CH2CHR9OC(O)R7]2X−
(iii) R6N+[CH2CHR9OC(O)R7]2X−
(iv) R6N+[CH2CHR9OH—] [CH2CH2NHC(O)R7]2X−,
where R6, R7 and X are each as defined for formula (i) above.
The —C(O)R7 fragment is preferably a fat-containing acyl group. Usable fat-containing acyl groups are derived from the natural sources of the triglycerides, preferably tallow, vegetable oils, partly hydrogenated tallow and partly hydrogenated vegetable oils. Usable sources of the triglycerides are, for example, soybean oil, tallow, partially hydrogenated tallow, palm oil, palm kernels, rapeseeds, porcine fat, coconut, rape, safflower oil, maize, rice and tall oil, and mixtures of these components.
The person skilled in the art is aware that the composition of the fatty acid-containing compounds is subject to certain natural variations, depending on the harvest or on the variety of the vegetable oil sources. The R7 groups are usually mixtures of the linear and branched carbon chains of the saturated and unsaturated aliphatic fatty acids.
The proportion of unsaturated R7 groups in such mixtures is preferably at least 10%, more preferably at least 25% and most preferably 40% to 70%. The proportion of polyunsaturated R7 groups in such mixtures is less than 10%, preferably less than 5% and more preferably less than 3%. If required, partial hydrogenation can be carried out in order to raise the saturated character and hence to improve the stability (for example odour, colour, etc.) of the end product. The content of unsaturated fractions, expressed by the iodine number, should be within a range of 5 to 150 and preferably within a range of 5 to 50. The ratio of cis and trans isomers of the double bonds in the unsaturated R7 groups is preferably greater than 1:1 and more preferably in the range of 4:1 to 50:1.
Preferred examples of the compounds of the formula (i) are: N,N-di(tallowyloxyethyl)-N,N-dimethylammonium chloride; N,N-di(canolyloxyethyl)-N,N-dimethylammonium chloride; N,N-di(tallowyloxyethyl)-N-methyl,N-(2-hydroxy-ethyl)ammonium methylsulphate; N,N-di(canolyloxyethyl)-N-methyl,N-(2-hydroxyethyl)ammonium methylsulphate; N,N-di(tallowylamidoethyl)-N-methyl,N-(2-hydroxyethyl)-ammonium methylsulphate; N,N-di(2-tallowyloxy-2-oxo-ethyl)-N,N-dimethylammonium chloride; N,N-di(2-canolyl-oxy-2-oxo-ethyl)-N,N-dimethylammonium chloride; N,N-di(2-tallowyloxyethylcarbonyloxyethyl)-N,N-dimethyl-ammonium chloride; N,N-di(2-canolyloxyethylcarbonyl-oxyethyl)-N,N-dimethylammonium chloride; N-(2-tallowyl-oxy-2-ethyl)-N-(2-tallowyloxy-2-oxoethyl)-N,N-dimethyl-ammonium chloride; N-(2-canolyloxy-2-ethyl)-N-(2-canolyl-oxy-2-oxoethyl)-N,N-dimethylammonium chloride; N,N,N-tri-(tallowyloxyethyl)-N-methylammonium chloride; N,N,N-tri-(canolyloxyethyl)-N-methylammonium chloride; 1,2-ditallowyloxy-3-N,N,N-trimethylammoniumpropyl chloride; and 1,2-dicanolyloxy-3-N,N,N-trimethylammoniumpropyl chloride.
Further preferred quaternary ammonium salts are ditallowdimethylammonium chloride, ditallowdimethylammonium methylsulphate, dimethylammonium chloride, di(hydrogenated tallow)distearyldimethylammonium chloride and dibehenyldimethylammonium chloride.
In a preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a pyridinium ion (XIIIa)
in which
R is as defined above for formula IX, one of the R1 to R5 radicals is methyl, ethyl or chlorine and the remaining R1 to R5 radicals are each hydrogen;
R3 is dimethylamino and the remaining R1, R2, R4 and R5 radicals are each hydrogen; all R1 to R5 radicals are each hydrogen;
R2 is carboxyl or carboxamide and the remaining R1, R2, R4 and R5 radicals are each hydrogen; or
R1 and R2 or R2 and R3 are 1,4-buta-1,3-dienylene and the remaining R1, R2, R4 and R5 radicals are each hydrogen. The cation [A]+ is preferably a pyridinium ion (XIIIa) in which
R1 to R5 are each hydrogen; or one of the R1 to R5 radicals is methyl or ethyl and the remaining R1 to R5 radicals are each hydrogen.
The ionic liquid most preferably has, as the cation, a pyridinium ion (XIIIa) selected from 1-methylpyridinium, 1-ethylpyridinium, 1-(1-butyl)pyridinium, 1-(1-hexyl)-pyridinium, 1-(1-octyl)pyridinium, 1-(1-hexyl)pyridinium, 1-(1-octyl)pyridinium, 1-(1-dodecyl)pyridinium, 1-(1-tetradecyl)pyridinium, 1-(1-hexadecyl)pyridinium, 1,2-dimethylpyridinium, 1-ethyl-2-methylpyridinium, 1-(1-butyl)-2-methylpyridinium, 1-(1-hexyl)-2-methylpyridinium, 1-(1-octyl)-2-methylpyridinium, 1-(1-dodecyl)-2-methylpyridinium, 1-(1-tetradecyl)-2-methylpyridinium, 1-(1-hexadecyl)-2-methylpyridinium, 1-methyl-2-ethylpyridinium, 1,2-diethylpyridinium, 1-(1-butyl)-2-ethyl-pyridinium, 1-(1-hexyl)-2-ethylpyridinium, 1-(1-octyl)-2-ethylpyridinium, 1-(1-dodecyl)-2-ethylpyridinium, 1-(1-tetradecyl)-2-ethylpyridinium, 1-(1-hexadecyl)-2-ethylpyridinium, 1,2-dimethyl-5-ethylpyridinium, 1,5-diethyl-2-methylpyridinium, 1-(1-butyl)-2-methyl-3-ethylpyridinium, 1-(1-hexyl)-2-methyl-3-ethylpyridinium and 1-(1-octyl)-2-methyl-3-ethylpyridinium, 1-(1-dodecyl)-2-methyl-3-ethylpyridinium, 1-(1-tetradecyl)-2-methyl-3-ethylpyridinium and 1-(1-hexadecyl)-2-methyl-3-ethylpyridinium.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a pyridazinium ion (XIIIb)
in which
R1 to R4 are each hydrogen, or one of the R1 to R4 radicals is methyl or ethyl and the remaining R1 to R4 radicals are each hydrogen,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a pyrimidinium ion (XIIIc)
in which
R1 is hydrogen, methyl or ethyl and
R2 to R4 are each independently hydrogen or methyl or
R1 is hydrogen, methyl or ethyl,
R2 and R4 are each methyl and
R3 is hydrogen,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a pyrazinium ion (XIIId)
where
R1 is hydrogen, methyl or ethyl and
R2 to R4 are each independently hydrogen or methyl,
R1 is hydrogen, methyl or ethyl,
R2 and R4 are each methyl and
R3 is hydrogen,
R1 to R4 are each methyl or
R1 to R4 are each methyl or hydrogen,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a pyrazolium ion (XIIIf), (XIIIg) or (XIIIg′)
where
R1 is hydrogen, methyl or ethyl and
R2 to R4 are each independently hydrogen or methyl,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a pyrazolium ion (XIIIh)
in which
R1 to R4 are each independently hydrogen or methyl.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a 1-pyrazolinium ion (XIIIi)
in which
R1 to R6 are each independently hydrogen or methyl,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a 2-pyrazolinium ion (XIIIj)
in which
R1 is hydrogen, methyl, ethyl or phenyl and
R2 to R6 are each independently hydrogen or methyl.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a 3-pyrazolinium ion (XIIIk) or (XIIIk′)
in which
R1 and R2 are each independently hydrogen, methyl, ethyl or phenyl and
R3 to R6 are each independently hydrogen or methyl.
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is an imidazolinium ion (XIIIl)
in which
R1 and R2 are each independently hydrogen, methyl, ethyl, 1-butyl or phenyl,
R3 and R4 are each independently hydrogen, methyl or ethyl and
R5 and R6 are each independently hydrogen or methyl.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is an imidazolinium ion (XIIIm) or (XIIIm′)
in which
R1 and R2 are each independently hydrogen, methyl or ethyl and
R3 to R6 are each independently hydrogen or methyl,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is an imidazolinium ion (XIIIn) or (XIIIn′)
in which
R1 to R3 are each independently hydrogen, methyl or ethyl and
R4 to R6 are each independently hydrogen or methyl,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a thiazolium ion (XIIIo) or (XIIIo′) or an oxazolium ion (XIIIp)
in which
R1 is hydrogen, methyl, ethyl or phenyl and
R2 and R3 are each independently hydrogen or methyl,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a 1,2,4-triazolium ion (XIIIq), (XIIIq′) or (XIIIq″)
in which
R1 and R2 are each independently hydrogen, methyl, ethyl or phenyl and
R3 is hydrogen, methyl or phenyl,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a 1,2,3-triazolium ion (XIIIr), (XIIIr′) or (XIIIr″)
in which
R1 is hydrogen, methyl or ethyl and
R2 and R3 are each independently hydrogen or methyl or R2 and R3 together are 1,4-buta-1,3-dienylene,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a pyrrolidinium ion (XIIIs)
in which
R1 is hydrogen, methyl, ethyl or phenyl and
R2 to R9 are each independently hydrogen or methyl,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is an imidazolidinium ion (XIIIt)
in which
R1 and R4 are each independently hydrogen, methyl, ethyl or phenyl and
R2 and R3 and also R5 to R8 are each independently hydrogen or methyl,
R is as defined above for formula IX.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is an ammonium ion (IV)
in which
R is as defined above for formula IX,
R1 to R3 are each independently C1-C18-alkyl or
R1 to R3 are each independently hydrogen or C1-C18-alkyl and
R4 is 2-hydroxyethyl, or
R1 and R2 together are 1,5-pentylene or 3-oxa-1,5-pentylene and
R3 is C1-C18-alkyl, 2-hydroxyethyl or 2-cyanoethyl.
Particularly preferred ammonium ions (IV) include, in particular, methyltri(1-butyl)ammonium, 2-hydroxyethyl-ammonium, bis(2-hydroxyethyl)dimethylammonium, N,N-di-methylpiperidinium and N,N-dimethylmorpholinium.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a guanidinium ion (IVv),
in which
R is as defined above for formula IX,
R1 to R5 are each methyl,
R1 to R5 are each independently C1-C18-alkyl or
R1 to R5 are each independently hydrogen or C1-C18-alkyl or 2-hydroxyethyl.
A very particularly preferred guanidinium ion (IVv) is N,N,N′,N′,N″,N″-hexamethylguanidinium.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a derivative of an ethanolamine, e.g. a cholinium ion (XIIIw), or of a diethanolamine (XIIIw′) or of a triethanolamine (XIIIw″)
in which
R is as defined above for formula IX,
R1 and R2 are each independently methyl, ethyl, 1-butyl or 1-octyl and
R3 is hydrogen, methyl, ethyl, acetyl, —SO2OH or —PO(OH)2, or
R1 is methyl, ethyl, 1-butyl or 1-octyl, R2 is a —CH2-CH2—OR4 group and
R3 and R4 are each independently hydrogen, methyl, ethyl, acetyl, -SO2OH or —PO(OH)2, or
R1 is a —CH2-CH2—OR4 group,
R2 is a —CH2-CH2—OR5 group and
R3 to R5 are each independently hydrogen, methyl, ethyl, acetyl, —SO20H or —PO(OH)2, or
R1 is methyl, ethyl, 1-butyl, 1-octyl, acetyl, —SO2OH, or —PO(OH)2 and
R3 to R5 are each independently hydrogen, methyl, ethyl, acetyl, —SO2OH, —PO(OH)2, or —(CnH2nO)mR1 where
n=1 to 5 and
m=1 to 100.
In a further preferred embodiment of the present invention, the ionic liquids used in the cleaning composition are those in which the cation [A]+ is a phosphonium ion (VI) in which R1 to R3 are each independently C1-C18-alkyl, in particular butyl, isobutyl, 1-hexyl or 1-octyl.
Among the abovementioned cations, the pyridinium ions (XIIIa), imidazolium ions (XII) and ammonium ions (IV) are particularly preferred as cations. Most preferably, the ionic liquids used in the inventive cleaning compositions are those which have one or more cations selected from 1-methylpyridinium, 1-ethylpyridinium, 1-(1-butyl)pyridinium, 1-(1-hexyl)pyridinium, 1-(1-octyl)-pyridinium, 1-(1-hexyl)pyridinium, 1-(1-octyl)pyridinium, 1-(1-dodecyl)pyridinium, 1-(1-tetradecyl)pyridinium, 1-(1-hexadecyl)pyridinium, 1,2-dimethylpyridinium, 1-ethyl-2-methylpyridinium, 1-(1-butyl)-2-methyl-pyridinium, 1-(1-hexyl)-2-methylpyridinium, 1-(1-octyl)-2-methylpyridinium, 1-(1-dodecyl)-2-methylpyridinium, 1-(1-tetradecyl)-2-methylpyridinium, 1-(1-hexadecyl)-2-methylpyridinium, 1-methyl-2-ethylpyridinium, 1,2-diethylpyridinium, 1-(1-butyl)-2-ethylpyridinium, 1-(1-hexyl)-2-ethylpyridinium, 1-(1-octyl)-2-ethylpyridinium, 1-(1-dodecyl)-2-ethylpyridinium, 1-(1-tetra-decyl)-2-ethylpyridinium, 1-(1-hexadecyl)-2-ethylpyridinium, 1,2-dimethyl-5-ethylpyridinium, 1,5-diethyl-2-methylpyridinium, 1-(1-butyl)-2-methyl-3-ethylpyridinium, 1-(1-hexyl)-2-methyl-3-ethylpyridinium, 1-(1-octyl)-2-methyl-3-ethylpyridinium, 1-(1-dodecyl)-2-methyl-3-ethylpyridinium, 1-(1-tetradecyl)-2-methyl-3-ethylpyridinium, 1-(1-hexadecyl)-2-methyl-3-ethylpyridinium, 1-methylimidazolium, 1-ethylimidazolium, 1-(1-butyl)imidazolium, 1-(1-octyl)imidazolium, 1-(1-dodecyl)imidazolium, 1-(1-tetradecyl)imidazolium, 1-(1-hexadecyl)imidazolium, 1,3-dimethylimidazolium, 1-ethyl-3-methylimidazolium, 1-(1-butyl)-3-methylimidazolium, 1-(1-hexyl)-3-methylimidazolium, 1-(1-octyl)-3-methylimidazolium, 1-(1-dodecyl)-3-methylimidazolium, 1-(1-tetradecyl)-3-methylimidazolium, 1-(1-hexadecyl)-3-methylimidazolium, 1,2-dimethylimidazolium, 1,2,3-trimethylimidazolium, 1-ethyl-2,3-dimethylimidazolium, 1-(1-butyl)-2,3-dimethylimidazolium, 1-(1-hexyl)-2,3-dimethylimidazolium, and 1-(1-octyl)-2,3-dimethylimidazolium, 1,4-dimethylimidazolium, 1,3,4-trimethylimidazolium, 1,4-dimethyl-3-ethylimidazolium, 3-butyl-imidazolium, 1,4-dimethyl-3-octylimidazolium, 1,4,5-trimethylimidazolium, 1,3,4,5-tetramethylimidazolium, 1,4,5-trimethyl-3-ethylimidazolium, 1,4,5-trimethyl-3-butylimidazolium, 1,4,5-trimethyl-3-octylimidazolium and 2-hydroxyethylammonium as cations.
The metal cations [M1]+, [M2]+, [M3]+, [M4]2+ and [M5]3+ mentioned in the formulae (IIIa) to (IIIj) are preferably metal cations of groups 1, 2, 6, 7, 8, 9, 10, 11, 12 and 13 of the Periodic Table. Particularly preferred metal cations are, for example, Li+, Na+, K+, Cs+, Mg2+, Ca2+, Ba2+, Cr3+, Fe2+, Fe3+, Co2+, Ni2+, Cu2+, Ag+, Zn2+ and Al3+.
The ionic liquids used with preference in accordance with the invention consist of at least one of the above-mentioned cations combined with at least one anion in each case. Usable anions are in principle all anions which, in conjunction with the cation, lead to an ionic liquid.
The anion [Y]n− of the ionic liquid may, for example, be selected from:
the group of halides and halogen-containing and halogen-like compounds of the formulae: F−, Cl−, Br−, I−, BF4−, PF6−, AlCl4−, Al2Cl7−, Al3Cl10−, AlBr4−, FeCl4−, BCl4−, SbF6−, AsF6−, ZnCl3−, SnCl3−, CuCl2−, CF3SO3−, (CF3SO3−)2N−, CF3CO2−, CCl3CO2−, CN−, SCN−, OCN−, NO2−, NO3−, N(CN)−;
the group of sulphates, sulphites and sulphonates of the general formulae: SO42−, HSO4−, SO32+, HSO3−, RaOSO3−, RaSO3−;
the group of phosphates of the general formulae: PO43−, HPO42−, H2PO4−, RaPO42−, HRaPO4−, RaRbPO4−;
the group of phosphonates and phosphinates of the general formulae: RaHPO3−, RaRbPO2−, RaRbPO3−;
the group of phosphites of the general formulae: PO33−, HPO32−, H2PO32−, RaPO32−, RaHPO3−, RaRbPO3−;
the group of phosphonites and phosphinites of the general formulae: RaRbPO2−, RaHPO2−, RaRbPO−, RaHPO−;
the group of carboxylates of the general formula: RaCOO−;
the group of borates of the general formulae: BO33−, HBO32−, H2BO3−, RaRbBO3−, RaHBO3−, RaBO32−, B(ORa) (ORb) (ORc) (ORd)−, B(HSO4)−, B(RaSO4)−;
the group of boronates of the general formulae: RaBO22−, RaRbBO−;
the group of carbonates and carbonic esters of the general formulae: HCO3−, CO32−, RaCO3−;
the group of silicates and silicic esters of the general formulae: SiO4−, HSiO43−, H2SiO42−, H3SiO4−, RaSiO43−, RaRbSiO42−, RaRbRcSiO42−, HRaSiO42−, H2RaSiO4−, HRaRbSiO4−;
the group of alkylsilane or arylsilane salts of the general formulae: RaSiO33, RaRbSiO22−, RaRbRcSiO−, RaRbRcSiO3−, RaRbRcSiO32−, RaRbSiO32−;
the group of carboximides, bis(sulphonyl)imides and sulphonylimides of the general formulae:
the group of methides of the general formula:
the group of alkoxides and aryl oxides of the general formula: RaO−;
the group of the halometallates of the general formula [MrHalt]s−, where M is a metal and Hal is fluorine, chlorine, bromine or iodine, r and t are positive integers and indicate the stoichiometry of the complex and s is a positive integer and indicates the charge of the complex;
the group of sulphides, hydrogensulphides, polysulphides, hydrogenpolysulphides and thiolates of the general formulae: S2−, HS−, [Sv]2−, [HSv]−, [RaS]−, where v is a positive integer from 2 to 10;
the group of complex metal ions such as Fe(CN)63−, Fe(CN)64−, MnO4−, Fe(CO)4−,
where Ra, Rb, Rc and Rd may each independently be: hydrogen;
C1-C30-alkyl or an aryl-, heteroaryl-, cycloalkyl-, halogen-, hydroxy-, amino-, carboxyl-, formyl-, —O—, —CO—, —CO—O— or —CO—N-substituted derivative thereof, for example methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl (tert-butyl), 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1-butyl, 3-methyl-l-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 2,2-dimethyl-1-propyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3-dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosyl, henicosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, triacontyl, phenylmethyl (benzyl), diphenylmethyl, triphenylmethyl, 2-phenylethyl, 3-phenylpropyl, cyclopentylmethyl, 2-cyclopentylethyl, 3-cyclopentylpropyl, cyclohexylmethyl, 2-cyclohexylethyl, 3-cyclohexylpropyl, methoxy, ethoxy, formyl, acetyl or CqF2(q−a)+(1−b)H2a+b where q<30, 0 ≦a≦q and b=0 or 1 (for example CF3, C2F5, CH2CH2-C(q−2)F2(q−2)+1, C6F13, C8F17, C10F21, C12F25);
C3-C12-cycloalkyl or an aryl-, heteroaryl-, cycloalkyl-, halogen-, hydroxy-, amino-, carboxy-, formyl-, —O—, —CO— or —CO——O—-substituted derivative thereof, for example cyclopentyl, 2-methyl-1-cyclopentyl, 3-methyl-1-cyclopentyl, cyclohexyl, 2-methyl-1-cyclohexyl, 3-methyl-1-cyclohexyl, 4-methyl-1-cyclohexyl or CqF2(q−a)-(1−b)H2a−b where q≦30, 0 ≦a≦q and b=0 or 1;
C2-C30-alkenyl or an aryl-, heteroaryl-, cycloalkyl-, halogen-, hydroxy-, amino-, carboxy-, formyl-, —O—, —CO— or —CO—O—-substituted derivative thereof, for example 2-propenyl, 3-butenyl, cis-2-butenyl, trans-2-butenyl or CqF2(q-a)-(1-b)H2a-b where q≦30, 0 ≦a≦q and b=0 or 1;
C3-C12-cycloalkenyl or an aryl-, heteroaryl-, cycloalkyl-, halogen-, hydroxy-, amino-, carboxy-, formyl-, —O—, —CO— or —CO—O—-substituted analogues thereof, for example 3-cyclopentenyl, 3-cyclohexenyl, 3-cyclohexenyl, 2,5-cyclohexadienyl or CqF2(q−a)-3(1-b)H2a−3b where q≦30, 0 ≦a≦q and b=0 or 1;
aryl or heteroaryl having from 2 to 30 carbon atoms or an alkyl-, aryl-, heteroaryl-, cycloalkyl-, halogen-, hydroxy-, amino-, carboxy-, formyl-, —O—, —CO— or —CO—O—-substituted analogues thereof, for example phenyl, 2-methylphenyl (2-tolyl), 3-methylphenyl (3-tolyl), 4-methylphenyl, 2-ethylphenyl, 3-ethylphenyl, 4-ethylphenyl, 2,3-dimethylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl, 2,6-dimethylphenyl, 3,4-dimethylphenyl, 3,5-dimethylphenyl, 4-phenylphenyl, 1-naphthyl, 2-naphthyl, 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, 2-pyridinyl, 3-pyridinyl, 4-pyridinyl or C6F(5−a)Ha where 0 ≦a≦5; or
two radicals form an unsaturated, saturated or aromatic ring which may be substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and/or heterocycles and may be interrupted by one or more oxygen and/or sulphur atoms and/or one or more substituted or unsubstituted imino groups.
The ionic liquids used in accordance with the invention preferably have anions selected from halides, carboxylates, phosphates, thiocyanates, isothiocyanates, dicyanamides, sulphates, alkylsulphates, sulphonates, alkylsulphonates, tetrafluoroborate, hexafluorophosphate and bis(trifluoromethylsulphonyl)imide.
Preferred anions are chloride, bromide, iodide, thiocyanate, hexafluorophosphate, trifluoromethanesulphonate, methanesulphonate, formate, acetate, glycolate, lactate, mandelate, nitrate, nitrite, trifluoroacetate, sulphate, hydrogensulphate, methylsulphate, ethylsulphate, 1-propylsulphate, 1-butylsulphate, 1-hexylsulphate, 1-octylsulphate, phosphate, dihydrogenphosphate, hydrogenphosphate, C1-C4-dialkylphosphates, propionate, tetrachloroaluminate, Al2Cl7−, chlorozincate, chloroferrate, bis(trifluoromethylsulphonyl)imide, bis(pentafluoroethylsulphonyl)imide, bis(methylsulphonyl)imide, bis(p-toluenesulphonyl)imide, tris(trifluoromethylsulphonyl)methide, bis(pentafluoroethylsulphonyl)methide, p-toluenesulphonate, tetracarbonyl cobaltate, dimethylene glycol monomethyl ether sulphate, oleate, stearate, acrylate, methacrylate, maleate, hydrogencitrate, vinylphosphonate, bis(pentafluoroethyl)phosphinate, borates such as bis[salicylato(2-)]borate, bis[oxalato(2-)]-borate, bis[1,2-benzoldiolato(2-)—O,O′]borate, tetracyanoborate, tetrafluoroborate, dicyanamide, tris(pentafluoroethyl)trifluorophosphate, tris(heptafluoropropyl)-trifluorophosphate, cyclic arylphosphates such as catecholphosphate (C6H4O2)P(O)O− or chlorocobaltate.
Particularly preferred anions are anions from the group consisting of halides, bis(perfluoroalkylsulphonyl)amides and bis(perfluoroalkylsulphonyl)imides such as bis(trifluoromethylylsulphonyl)imide, alkyltosylates and aryltosylates, perfluoroalkyltosylates, nitrate, sulphate, hydrogensulphate, alkylsulphates and arylsulphates, polyether sulphates and sulphonates, perfluoroalkylsulphates, sulphonate, alkylsulphonates and arylsulphonates, perfluorinated alkylsulphonates and arylsulphonates, alkylcarboxylates and arylcarboxylates, perfluoroalkylcarboxylates, perchlorate, tetrachloroaluminate, saccharinate, dicyanamide, thiocyanate, isothiocyanate, tetraphenylborate, tetrakis(pentafluorophenyl)borate, tetrafluoroborate, hexafluorophosphate, polyether phosphates, dialkylphosphates and phosphates.
Very particularly preferred anions are chloride, bromide, hydrogensulphate, tetrachloroaluminate, thiocyanate, methylsulphate, ethylsulphate, methanesulphonate, formate, acetate, glycolate, lactate, dimethylphosphate, diethylphosphate, p-toluenesulphonate, tetrafluoroborate and hexafluorophosphate.
The ionic liquids or mixtures thereof used in the cleaning composition are most preferably those which contain a combination of a 1,3-dialkylimidazolium, 1,2,3-trialkylimidazolium, 1,3-dialkylimidazolinium or 1,2,3-trialkylimidazolinium cation with an anion selected from the group consisting of halides, bis(trifluoromethylylsulphonyl)imide, perfluoroalkyl tosylates, alkyl sulphates and alkylsulphonates, perfluorinated alkylsulphonates and alkyl sulphates, perfluoroalkyl carboxylates, perchlorate, dicyanamide, thiocyanate, isothiocyanate, tetraphenylborate, tetrakis(pentafluorophenyl)borate, tetrafluoroborate, hexafluorophosphate, dimethylphosphate and diethylphosphate.
The ionic liquids used in the inventive composition may also be commercially available, acyclic quaternary ammonium salts, for example quaternary fatty amine ethoxylate (TEGO® IL T16ES), cocoalkylpentaethoxymethylammonium ethosulphate (TEGO® IL K5MS), distearyldimethylammonium chloride (TEGO® IL DS) or else dimethyldi(hydroxyethyl)ammonium methylsulphonate (TEGO® IL 2MS). The ionic liquids mentioned are available from Evonik Goldschmidt GmbH.
The inventive cleaning composition preferably comprises an ionic liquid or a mixture of ionic liquids which has a melting point below 100° C., preferably below 50° C. More preferably, the ionic liquids used in the inventive composition or the mixture of ionic liquids have a melting point below room temperature.
Preferred compositions are those which comprise ionic liquids or mixtures of ionic liquids which are present in liquid form at a temperature of −50° C. to 400° C., preferably of −40° C. to 280° C. and more preferably of −30° C. to 150° C.
Particularly preferred compositions are those in which the ionic liquid or the mixture of ionic liquids has a decomposition temperature of greater than 200° C.
The inventive compositions preferably comprise ionic liquids or mixtures of ionic liquids which are soluble in water and/or organic solvents.
Very particular preference is given to using, in the inventive compositions, those ionic liquids or mixtures of ionic liquids which have both hydrophilic and hydrophobic domains as a detergent.
It may be advantageous when the ionic liquids present in the compositions are those which are biodegradable and simultaneously non-toxic. This has the advantage that residues of the cleaning composition which may be present in the cleaned substrate do not lead to any damage to the environment or humans. Such ionic liquids are used especially when the cleaning composition is used to clean articles which come into contact with the human skin, for example items of clothing.
The inventive composition may, as well as the compressed gas and one or more ionic liquids, comprise, as a detergent, further detergents which are not ionic liquids, especially those which are soluble in ionic liquids.
Such further detergents may, for example, be:
Likewise useful as further detergents are organomodified siloxanes, for example: polyethersiloxanes, for example those as obtainable under the trade names TEGOPREN® or the name series TEGO® WET.
Particularly suitable polyethersiloxane derivatives are those of the following general formula (XV):
where
the Rf radical may be the R1 radical, where
R1 is an alkyl radical having 1 to 4 carbon atoms or an aryl radical, or
Rf is the R2 or R3 radical, with the proviso that at least one Rf radical is the R2 radical, where R2 and R3 are each independently polyether radicals of the formula (XVI)
(F)q(O(C2H4−dR′dO)m(CxH2xO)rZ)w (XVI)
where
d is 1 to 3
m is >1
q is 0 or 1
x is 2 to 10
r is >1
w is 1 to 4
F is a hydrocarbon radical which may also be branched,
R′ is a hydrogen radical, a monovalent hydrocarbon radical having 1 to 18 carbon atoms,
Z is a hydrogen atom or a monovalent organic radical such as alkyl, or alkyl or aryl ester, and where, in formula (XV):
b is 0 to 8,
a is 1 to 100 when b is 6 to 8,
a is 1 to 200 when b is 3 to 6,
a is 1 to 300 when b is 0 to 3.
The values of a and b should be understood as average values since the silicone polyether copolymers used in accordance with the invention are present in the form of randomly equilibrated mixtures.
The R1 radicals are alkyl radicals having 1 to 4 carbon atoms, such as methyl, ethyl, propyl or butyl radicals, or aryl radicals, preference being given to the phenyl radicals. As a result of preparation and cost considerations, the methyl radicals are preferred, and so preferably at least 80% of the R1 radicals are methyl radicals. Particular preference is given to those polysiloxanes in which all R1 radicals are methyl radicals.
The siloxane mixture may be straight-chain (b=0) or branched (b>0 to 8). Experience has shown that the value of a can be combined with values of b only in the manner specified, since the increased viscosity otherwise makes handling impossible.
Particularly preferred silicone polyether copolymers are those of the general formula (XVII)
in which
m=0 to 30,
k=1 to 5,
R1 is an allyl alcohol- or alkyl-started polyether which has been reacted with 1 to 10 ethylene oxide molecules and between 1 and 25 propylene oxide molecules.
The organomodified siloxanes used may also be functionalized polyethersiloxanes, as supplied, for example, under the product name TEGOPREN® 7100 by Evonik Goldschmidt GmbH.
The organomodified siloxanes used may also be polyether-siloxanes of blockwise structure.
Suitable polyethersiloxanes of blockwise structure are, for example, structures of the formula (XVIII)
where
the A radical is a polyoxyalkylene block of average formula (XIX)
[(C2H4−dR′dO)n(CxH2xO)r(C2H4−dR″dO)t] (XIX)
where
d is 1 to 3,
n is ≧0,
x is 2 to 10,
r is ≧0,
t is ≧0,
n+r+t is ≧1, and
R′ is a monovalent aromatic, optionally substituted hydrocarbon radical,
R″ is a hydrogen radical or a monovalent hydrocarbon radical having 1 to 18 and preferably 1 to 2 carbon atoms,
R1 is a hydrogen atom, a monovalent organic linear or branched alkyl radical of chain length C1-C40 or a carboxyl radical of a branched or unbranched alkyl or aryl ester,
B is a polysiloxane block of average formula (XX)
where
R2 is the same or different and comprises an alkyl radical having 1 to 4 carbon atoms or a phenyl radical and
y is 5 to 200,
m is 2 to 100,
p is 0 or 1 and
q is 0 or 1, or of the formula (XXI)
where
the R1, A and B radicals and m, p and q are each as defined above and
C is a linear or branched alkylene radical having 2 to 20 carbon atoms.
The compounds of the structures specified are typically present in the form of random mixtures; the indices reported therefore correspond to the numerical mean values of the mixtures.
In addition, the further detergents used may be detergent formulations, as described, for example, in U.S. Pat. No. 5,858,022 (0.5% by weight of X-207 (a commercial detergent from Union Carbide—nonylphenyl ethoxylate having an HLB value (hydrophobic-lipophilic balance) of 10.5); 0.5% by weight of PDMS-g3-PEG (polydimethylsiloxane(PDMS)-graft-polyethylene glycol(PEG) copolymer) (500 g/mol PDMS with 350 g/mol of PEG grafts, approx. 50% of PEG); 1% by weight of SpanTm 80 (a commercial sorbitan ester surfactant from ICI); 0.5% by weight of isopropanol; 0.2% by weight of water; 30% by weight of Isopar™ (a commercially available hydrocarbon solvent from EXXON; made up to 100% by weight with CO2)).
In addition, further detergents used may be detergent formulations which are sold commercially under the brand name Fabritech®, e.g. Fabritech® 5565.
In addition, suitable further detergents are described in Eastoe et al. Langmuir 2006, 22, 9832 and in Hebach et al. Tenside Surf. Det. 42 (2005) 2 78-82.
As a result of the combination of ionic liquids as detergents with one or more of the abovementioned further detergents, the cleaning power can be improved further, especially in the case of lipophilic contaminants.
The mass ratio of ionic liquids to further detergents which are not ionic liquids is preferably from 100:1 to 1:100, preferentially 10:1 to 1:10, more preferably 5:1 to 1:5 and most preferably 2:1 to 1:2.
In addition to detergents, the inventive composition may comprise further additives which are preferably soluble in the ionic liquid(s). Such additives may, for example, be those which nourish, protect or modify the articles to be cleaned. The addition of such additives to the inventive composition allows complicated downstream treatment steps to be dispensed with. Examples are optical brighteners or bleaches, softeners, fragrances or enzymes.
The inventive cleaning compositions can be obtained by simple mixing of the components present.
The inventive cleaning compositions can be used especially in the process described below.
The process according to the invention for cleaning articles, in which the articles are contacted with a cleaning composition comprising a compressed gas and at least one detergent, is characterized in that an inventive cleaning composition is used.
The process can be carried out, for example, like conventional cleaning processes in which compressed gases are used. Such processes are described, for example, in U.S. Pat. No. 5,783,082 and the literature cited there.
The articles to be cleaned should be selected such that they are insoluble in one of the substances present in the cleaning composition.
The articles to be cleaned may, for example, be those selected from the group of textiles and yarns.
In a preferred embodiment of the process according to the invention, the article to be cleaned consists partly or completely of wool or a blend fabric which contains at least 30% by weight of wool, preferably 50% by weight of wool, more preferably >80% by weight of wool.
In a further preferred embodiment of the process according to the invention, the article to be cleaned consists partly or completely of silk or a blend fabric which contains at least 30% by weight of silk, preferably 50% by weight of silk, more preferably >80% by weight of silk.
In a further preferred embodiment of the process according to the invention, the article to be cleaned, preferably the textile or the yarn, comprises or consists of cotton or cotton blend fabric. The article to be cleaned preferably consists partly or completely of cotton or a blend fabric which comprises at least 30% by weight of cotton, preferably 50% by weight of cotton, more preferably >80% by weight of cotton. The articles to be cleaned may additionally also be those which have a surface which is wholly or partly composed of leather, which is completely or partly an animal or synthetic fur, or which is wholly or partly composed of metal, semimetal, plastic, lacquer, ceramic, wood, rubber or glass. The articles to be cleaned may preferably be items of clothing, electronic components, mechanical components, seals or packaging, especially when these articles are sensitive to water (corrosion) or air (oxidation).
The inventive cleaning composition, especially one which comprises liquid carbon dioxide as the compressed gas, can be used, for example, in a cleaning process for textiles in which liquid carbon dioxide is typically used. In such a cleaning process, the textiles to be cleaned are moved in a pressure-resistant laundry drum in the presence of the cleaning composition. The cleaning composition is preferably conducted and filtered in one cycle. At the end of the washing operation, the cleaning composition with all dissolved/dispersed substances can be discharged from the laundry drum into a second chamber. Once pressure equalization has taken place in the laundry drum, the cleaned laundry can be removed. In the second chamber the liquid CO2 can be distilled off and transferred to a reservoir vessel. The ionic liquids can be purified by suitable process steps to remove them from the residues which cannot be distilled easily, which are formed by the impurities and at least one ionic liquid. Such process steps may, for example, be distillation steps and/or extraction steps or the like. The impurities which are removed in this way or have already been removed in the filtration can be disposed of, and the purified ionic liquids can be reused in a further process step.
The examples adduced below describe the present invention by way of example, without any intention that the invention, whose scope of application is evident from the entire description and the claims, be restricted to the embodiments specified in the examples.
Working Examples:
Test Procedure:
In a high-pressure autoclave (capacity 600 ml), wash tests were carried out on test fabric with standardized stains, obtainable from WfK Testgewebe GmbH (standard cotton based on DIN 53919, WfK code 10A, basis weight: 170 g/m2, fibre count 270/270 threads/dm, weave: plain 1/1, yarn fineness: 295/295 dtex) and compressed CO2. The autoclave contained connections to a CO2 tank, such that filling and emptying was possible. The test fabric with standardized stains was secured in the autoclave and the appropriate additives were sprayed in via a valve. Thereafter, the autoclave was filled first with gaseous CO2 up to a pressure of 25-30 bar, then with about 150-200 g of liquid CO2. Subsequently, the autoclave was rotated for a certain time (wash time). After the cleaning had ended, the autoclave was kept in such a state that the cleaning liquid could flow out into a pressure vessel owing to gravity. From there, the CO2 was decompressed. The soil and the additives remained in the pressure vessel. The entire washing operation was then repeated once more without additives (rinse time). Finally, the test fabric with standardized stains was removed and assessed visually. The results of the 5 inventive formulations (Exp. 1 to 5), of the comparative formulation (V) and of the control formulation (Co) are reproduced in Table 1.
Inspection and assessment of the cleaned substrates: The test fabric with standardized stains was assessed (visually) after cleaning according to a five-level rating scheme as compared with uncleaned comparative fabric.
1=unchanged
2=slightly improved
3=improved
4=significantly improved
5=no residues
The results show clearly that the inventive formulations, as compared with industrial solutions used to date, lead to significant improvements in the case of hydrophilic stains.
The results also show that the combination of conventional detergents and ionic liquids as detergents allows a further improvement in the cleaning performance to be achieved.
Having thus described in detail various embodiments of the present invention, it is to be understood that the invention defined by the above paragraphs is not to be limited to particular details set forth in the above description as many apparent variations thereof are possible without departing from the spirit or scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102008040486.1 | Jul 2008 | DE | national |
