Patent Grant
7049279
This application is a 371 of PCT/EP00/11339 filed Nov. 16, 2000.
This invention relates generally to solid laundry detergents, dishwashing detergents and cleaning compositions and more particularly to new surfactant granules distinguished by an improved dissolving rate, to a process for their production and to their use.
Nowadays, surfactants are preferably used in granular, substantially water-free form for the production of solid laundry detergents, dishwashing detergents and cleaning compositions. Various processes have proved to be suitable for the production of granular, substantially water-free surfactants. However, one feature common to commercially available surfactant granules is that they have an inadequate dissolving rate, particularly in cold water. For this reason, detergent tablets based on anionic or nonionic surfactants cannot be directly placed in the dispensing compartment of washing machines, but instead have to be directly added to the wash liquor despite the use of considerable quantities of disintegrators.
Accordingly, the problem addressed by the present invention was to provide surfactant granules which, on contact with cold water, would disintegrate particularly quickly without forming a gel phase so that the disadvantages of the prior art would be reliably overcome.
The present invention relates to surfactant granules with an improved dissolving rate which are obtained by granulating and compacting surface-active proteins and/or protein derivatives, optionally together with anionic and/or nonionic surfactants, in the presence of disintegrators.
It has surprisingly been found that the granules according to the invention not only have excellent cleaning performance, they also have a significantly improved dissolving rate so that they may be used in particular for the production of detergent tablets which may be directly placed in the dispensing compartment of washing machines. The use of other disintegrators in the production of such tablets is often no longer necessary. Compared with conventional granules which must be said to “dissolve”, the granules according to the invention may be more accurately said to “disintegrate”. The surfactant is thus released and activated particularly quickly.
The present invention also relates to a process for the production of surfactant granules with an improved dissolving rate in which surface-active protesins and/or protein derivatives are granulated and compacted, optionally together with anionic and/or nonionic surfactants, in the presence of disintegrators.
Protein and Protein Hydrolyzates
The protein component is preferably formed by protein hydrolyzates and condensation products thereof with fatty acids and, to a lesser extent, by protein hydrolyzate esters and quaternized protein fatty acid condensates. Protein hydrolyzates are degradation products of animal or vegetable proteins, for example collagen, elastin or keratin, preferably almond and potato protein and more particularly wheat, rice and soya protein, which are obtained by acidic, alkaline and/or enzymatic hydrolysis and thereafter have an average molecular weight of 600 to 4,000 and preferably 2,000 to 3,500. Although protein hydrolyzates are not surfactants in the accepted sense because they lack a hydrophobic residue, they are often used for formulating surface-active compositions by virtue of their dispersing properties. Overviews of the production and use of protein hydrolyzates have been published, for example, by G. Schuster and A. Domsch in Seifen, Öle, Fette, Wachse, 108, 177 (1982) and Cosm. Toil. 99, 63 (1984), by H. W. Steisslinger in Parf. Kosm. 72, 556 (1991) and by F. Aurich et al. in Tens. Surf. Det. 29, 389 (1992). Vegetable protein hydrolyzates based on wheat gluten or rice protein, of which the production is described in German patents DE-C1 19502167 and DE-C1 19502168 (Henkel), are preferably used. So-called protein fatty acid condensates which are comparable in their properties with soaps can be obtained from the protein hydrolyzates by condensation with C6-22, preferably C12-18 fatty acids. Condensates of the above-mentioned hydrolyzates with hydrolyzates with caproic acid, caprylic acid, 2-ethyl hexanoic acid, capric acid, lauric acid, isotridecanoic acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, isostearic acid, oleic acid, elaidic acid, petroselic acid, linoleic acid, linolenic acid, elaeostearic acid, arachic acid, gadoleic acid, behenic acid and erucic acid are preferably used.
Anionic Surfactants
Typical examples of anionic surfactants which may be used together with the proteins or ptoein derivatives are soaps, alkyl benzenesulfonates, alkane sulfonates, olefin sulfonates, alkyl ether sulfonates, glycerol ether sulfonates, α-methyl ester sulfonates, sulfofatty acids, alkyl sulfates, fatty alcohol ether sulfates, glycerol ether sulfates, hydroxy mixed ether sulfates, monoglyceride (ether) sulfates, fatty acid amide (ether) sulfates, mono- and dialkyl sulfosuccinates, mono- and dialkyl sulfosuccinamates, sulfo-triglycerides, amide soaps, ether carboxylic acids and salts thereof, fatty acid isethionates, fatty acid sarcosinates, fatty acid taurides, N-acyl amino acids such as, for example, acyl lactylates, acyl tartrates, acyl glutamates and acyl aspartates, alkyl oligoglucoside sulfates, protein fatty acid condensates (especially wheat-based vegetable products) and alkyl (ether)phosphates. If the anionic surfactants contain polyglycol ether chains, the polyglycol ether chains may have a conventional homolog distribution, although they preferably have a narrow homolog distribution. Alkyl benzenesulfonates, alkyl sulfates, soaps, alkanesulfonates, olefin sulfonates, methyl ester sulfonates and mixtures thereof are preferably used. Preferred alkyl benzenesulfonates preferably correspond to formula (I):
R—Ph—SO3X (I)
in which R is a branched, but preferably linear alkyl group containing 10 to 18 carbon atoms, Ph is a phenyl group and X is an alkali metal and/or alkaline earth metal, ammonium, alkylammonium, alkanolammonium or glucammonium. Of these alkyl benzenesulfonates, dodecyl benzene-sulfonates, tetradecyl benzenesulfonates, hexadecyl benzenesulfonates and technical mixtures thereof in the form of the sodium salts are particularly suitable. Alkyl and/or alkenyl sulfates, which are also often referred to as fatty alcohol sulfates, are understood to be the sulfation products of primary and/or secondary alcohols which preferably correspond to formula (II):
R2O—SO3Y (II)
in which R2 is a linear or branched, aliphatic alkyl and/or alkenyl group containing 6 to 22 and preferably 12 to 18 carbon atoms and Y is an alkali metal and/or alkaline earth metal, ammonium, alkylammonium, alkanol-ammonium or glucammonium. Typical examples of alkyl sulfates which may be used in accordance with the invention are the sulfation products of caproic alcohol, caprylic alcohol, capric alcohol, 2-ethylhexyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, palmitoleyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, elaidyl alcohol, petroselinyl alcohol, arachyl alcohol, gadoleyl alcohol, behenyl alcohol and erucyl alcohol and the technical mixtures thereof obtained by high-pressure hydrogenation of technical methyl ester fractions or aldehydes from Roelen's oxosynthesis. The sulfation products may advantageously be used in the form of their alkali metal salts, more especially their sodium salts. Alkyl sulfates based on C16/18 tallow fatty alcohols or vegetable fatty alcohols with a comparable C-chain distribution in the form of their sodium salts are particularly preferred. In the case of branched primary types, the alcohols are oxo-alcohols which are obtainable, for example, by reacting carbon monoxide and hydrogen on α-olefins by the Shop process. Corresponding alcohol mixtures are commercially available under the trade names of Dobanol® or Neodol®. Suitable alcohol mixtures are Dobanol 91®, 23®, 25® and 45®. Another possibility are the oxoalcohols obtained by the standard oxo process of Enichema or Condea in which carbon monoxide and hydrogen are added onto olefins. These alcohol mixtures are a mixture of highly branched alcohols and are commercially available under the name of Lial®. Suitable alcohol mixtures are Lial 91®, 111®, 123®, 125®, 145®.
Nonionic Surfactants
The nonionic surfactants which may also be used as an additional surfactant component of the granules in accordance with the present invention are, for example, fatty alcohol polyglycol ethers, alkylphenol polyglycol ethers, fatty acid polyglycol esters, fatty acid amide polyglycol ethers, fatty amine polyglycol ethers, alkoxylated triglycerides, mixed ethers and mixed formals, alk(en)yl oligoglycosides, fatty acid-N-alkyl glucamides, protein hydrolyzates (more particularly wheat-based vegetable products), polyol fatty acid esters, sugar esters, sorbitan esters, polysorbates and amine oxides. If the nonionic surfactants contain polyglycol ether chains, the polyglycol ether chains may have a conventional homolog distribution, although they preferably have a narrow homolog distribution. Nonionic surfactants which can be dried off are preferably used, more particularly alkyl and alkenyl oligoglycosides which preferably correspond to formula (III):
R3O—[G]p (III)
in which R3 is an alkyl and/or alkenyl group containing 4 to 22 carbon atoms, G is a sugar unit containing 5 or 6 carbon atoms and p is a number of 1 to 10. They may be obtained by the relevant methods of preparative organic chemistry. EP 0 301 298 A1 and WO 90/03977 are cited as representative of the extensive literature available on the subject. The alkyl and/or alkenyl oligoglycosides may be derived from aldoses or ketoses containing 5 or 6 carbon atoms, preferably glucose. Accordingly, the preferred alkyl and/or alkenyl oligoglycosides are alkyl and/or alkenyl oligoglucosides. The index p in general formula (III) indicates the degree of oligomerization (DP), i.e. the distribution of mono- and oligoglycosides, and is a number of 1 to 10. Whereas p in a given compound must always be an integer and, above all, may assume a value of 1 to 6, the value p for a certain alkyl oligoglycoside is an analytically determined calculated quantity which is generally a broken number. Alkyl and/or alkenyl oligoglycosides having an average degree of oligomerization p of 1.1 to 3.0 are preferably used. Alkyl and/or alkenyl oligoglycosides having a degree of oligomerization of less than 1.7 and, more particularly, between 1.2 and 1.4 are preferred from the applicational point of view. The alkyl or alkenyl radical R3 may be derived from primary alcohols containing 4 to 11 and preferably 8 to 10 carbon atoms. Typical examples are butanol, caproic alcohol, caprylic alcohol, capric alcohol and undecyl alcohol and the technical mixtures thereof obtained, for example, in the hydrogenation of technical fatty acid methyl esters or in the hydrogenation of aldehydes from Roelen's oxosynthesis. Alkyl oligoglucosides having a chain length of C8 to C10 (DP=1 to 3), which are obtained as first runnings in the separation of technical C8-18 coconut oil fatty alcohol by distillation and which may contain less than 6% by weight of C12 alcohol as an impurity, and also alkyl oligo-glucosides based on technical C9/11 oxoalcohols (DP=1 to 3) are preferred. In addition, the alkyl or alkenyl radical R3 may also be derived from primary alcohols containing 12 to 22 and preferably 12 to 14 carbon atoms. Typical examples are lauryl alcohol, myristyl alcohol, cetyl alcohol, palmitoleyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, elaidyl alcohol, petroselinyl alcohol, arachyl alcohol, gadoleyl alcohol, behenyl alcohol, erucyl alcohol, brassidyl alcohol and technical mixtures thereof which may be obtained as described above. Alkyl oligoglucosides based on hydrogenated C12/14 cocoalcohol with a DP of 1 to 3 are preferred.
If proteins and/or protein derivatives on the one hand and anionic and nonionic surfactants on the other hand are used together, it is advisable to use them in a ratio by weight of 1:10 to 10:1, preferably 1:5 to 5:1 and more particularly 1:2 to 2:1. The proteins and/or protein derivatives and surfactants may be used—individually or together—both in the form of water-containing pastes with solids contents (=active substance contents) of, for example, 1 to 60, preferably 5 to 50 and more particularly 15 to 35% by weight or in the form of dry solids with residual water contents of typically below 10 and preferably below 5% by weight.
Disintegrators
Disintegrators are substances which are present in the surfactant granules to accelerate their disintegration on contact with water. Disintegrators are reviewed, for example, in J. Pharm. Sci. 61 (1972) and In Römpp Chemielexikon, 9th Edition, Vol. 6, page 4440. Viewed macroscopically, the disintegrators may be homogeneously distributed In the granules although, when observed under a microscope, they form zones of increased concentration due to their production. Preferred disintegrators include polysaccharides such as, for example, natural starch and derivatives thereof (carboxymethyl starch, starch glycolates in the form of their alkali metal salts, agar agar, guar gum, pectins, etc.), celluloses and derivatives thereof (carboxymethyl cellulose, microcrystalline cellulose), polyvinyl pyrrolidone, such as KOLLIDON™ (a product of BASF), alginic acid and alkali metal salts thereof (alginates), amorphous or even partly crystalline layer silicates (bentonltes), polyurethanes, polyethylene glycols and effervescent systems. Other disintegrators which may be present in accordance with the invention can be found, for example, in WO 98/40462 (Rettenmeyer), WO 98/55583 and WO 98/55590 (Unilever) and WO 98/40463, DE 19709991 and DIE 19710254 (Henkel). Reference is specifically made to the teaching of these documents. To produce the granules according to the invention, the surfactants and the disintegrators may be used in a ratio by weight of 1:10 to 10:1, preferably 1:5 to 5:1 and more particularly 1:2 to 2:1, based on their solids contents. In addition, it is advisable to adjust the water content of the disintegrators or the surfactant granules to such a value that swelling does not automatically occur during storage. The residual water content should preferably not exceed 10% by weight.
Granulation and Compacting
The production of the surfactant granules by granulation and compacting may be carried out by known methods used in the detergents field. More particularly, the granules may be compacted before, during or after granulation. Compacting is absolutely essential for obtaining a satisfactory increase in the dissolving rate.
A particularly preferred process for the production of the surfactant granules according to the invention comprises subjecting the mixtures to fluidized bed granulation (“SKET” granulation). SKET fluidized bed granulation is understood to be a simultaneous granulation and drying process preferably carried out in batches or continuously. The mixtures of surfactants and disintegrating agents may be used both in dried form and in the form of a water-containing preparation. Preferred fluidized-bed arrangements have base plates measuring 0.4 to 5 m. The SKET granulation is preferably carried out at fluidizing air flow rates of 1 to 8 m/s. The granules are preferably discharged from the fluidized bed via a sizing stage. Sizing may be carried out, for example, by means of a sieve or by an air stream flowing in countercurrent (sizing air) which is controlled in such a way that only particles beyond a certain size are removed from the fluidized bed while smaller particles are retained in the fluidized bed. The inflowing air is normally made up of the heated or unheated sizing air and the heated bottom air. The temperature of the bottom air is between 80 and 400° C. and preferably between 90 and 350° C. A starting material, preferably surfactant granules from an earlier test batch, is advantageously introduced at the beginning of the granulation process.
Other processes, for example compacting by extrusion or in a roller mill, are described in the following in the chapter headed “Production of laundry detergents, dishwashing detergents and cleaning compositions”. These processes may be analogously applied to the production of the surfactant granules according to the invention.
To facilitate processing in the processes mentioned, it has proved to be of advantage to add granulating and compacting aids, for example polyethylene glycol waxes, to the surfactant granules in quantities of 1 to 10 and preferably 2 to 5% by weight, based on the granules. Auxiliaries such as these improve the friction and adhesion behavior of the products and reduce energy consumption. If the required particle size distribution is not achieved by compacting alone, other steps, for example grading, may be added.
Commercial Applications
The present invention also relates to the use of the surfactant granules for the production of solid laundry detergents, dishwashing detergents and cleaning compositions in which they may be present in quantities of 1 to 90% by weight, preferably 5 to 50% by weight and more particularly 10 to 25% by weight, based on the detergent/cleaner. The detergents/cleaners may be present in the form of powders, granules, extrudates, agglomerates or, more particularly, tablets and may contain other typical ingredients.
Primary constituents of the detergents/cleaners may be, for example, other anionic, nonionic, cationic, amphoteric and/or zwitterionic surfactants although anionic surfactants or combinations of anionic and nonionic surfactants are preferably present providing they are not identical with the ingredients of the granules according to the invention.
The laundry detergents, dishwashing detergents and cleaning compositions may also contain inorganic and organic builders, suitable inorganic builders mainly being zeolites, crystalline layer silicates, amorphous silicates and—where permitted—also phosphates such as, for example, tripolyphosphate. The quantity of co-builder should be included in the preferred quantities of phosphates.
The finely crystalline, synthetic zeolite containing bound water often used as a detergent builder is preferably zeolite A and/or zeolite P. Zeolite MAP® (Crosfield) is a particularly preferred P-type zeolite. However, zeolite X and mixtures of A, X and/or P and also Y are also suitable. A co-crystallized sodium/potassium aluminium silicate of zeolite A and zeolite X commercially available as VEGOBOND AX® (from Condea Augusta S.p.A.) is also of particular interest. The zeolite may be used in the form of a spray-dried powder or even in the form of an undried stabilized suspension still moist from its production. Where the zeolite is used in the form of a suspension, the suspension may contain small additions of nonionic surfactants as stabilizers, for example 1 to 3% by weight, based on zeolite, of ethoxylated C12-18 fatty alcohols containing 2 to 5 ethylene oxide groups, C12-14 fatty alcohols containing 4 to 5 ethylene oxide groups or ethoxylated isotridecanols. Suitable zeolites have a mean particle size of less than 10 μm (volume distribution, as measured by the Coulter Counter method) and contain preferably 18 to 22% by weight and more preferably 20 to 22% by weight of bound water.
Suitable substitutes or partial substitutes for phosphates and zeolites are crystalline layer sodium silicates corresponding to the general formula NaMSixO2x+1.yH2O, where M is sodium or hydrogen, x is a number of 1.9 to 4 and y is a number of 0 to 20, preferred values for x being 2, 3 or 4. Crystalline layer silicates such as these are described, for example, in European patent application EP 0 164 514 A1. Preferred crystalline layer silicates corresponding to the above formula are those in which M is sodium and x assumes the value 2 or 3. Both β- and δ-sodium disilicates Na2Si2O5.yH2O are particularly preferred, β-sodium disilicate being obtainable, for example, by the process described in International patent application WO 91/08171. Other suitable layer silicates are known, for example, from patent applications DE 2334899 A1, EP 0026529 A1 and DE 3526405 A1. The suitability of these layer silicates is not limited to a particular composition or structural formula. However, smectites, more especially bentonites, are preferred for the purposes of the present invention. Suitable layer silicates which belong to the group of water-swellable smectites are, for example, those corresponding to the following general formulae:
where x=0 to 4, y=0 to 2 and z=0 to 6. Small amounts of iron may additionally be incorporated in the crystal lattice of the layer silicates corresponding to the above formulae. In addition, by virtue of their ion-exchanging properties, the layer silicates may contain hydrogen, alkali metal and alkaline-earth metal ions, more particularly Na+ and Ca2+. The quantity of water of hydration is generally in the range from 8 to 20% by weight and is dependent upon the degree of swelling or upon the treatment method. Suitable layer silicates are known, for example, from U.S. Pat. No. 3,966,629 U.S. Pat. No. 4,062,647, EP 0026529 A1 and EP 0028432 A1. Layer silicates which, by virtue of an alkali treatment, are largely free from calcium ions and strongly coloring iron ions are preferably used.
Other preferred builders are amorphous sodium silicates with a modulus (Na2O:SiO2 ratio) of 1:2 to 1:3.3, preferably 1:2 to 1:2.8 and more preferably 1:2 to 1:2.6 which dissolve with delay and exhibit multiple wash cycle properties. The delay in dissolution in relation to conventional amorphous sodium silicates can have been obtained in various ways, for example by surface treatment, compounding, compacting or by overdrying. In the context of the invention, the term “amorphous” is also understood to encompass “X-ray amorphous”. In other words, the silicates do not produce any of the sharp X-ray reflexes typical of crystalline substances in X-ray diffraction experiments, but at best one or more maxima of the scattered X-radiation which have a width of several degrees of the diffraction angle. Particularly good builder properties may even be achieved where the silicate particles produce crooked or even sharp diffraction maxima in electron diffraction experiments. This may be interpreted to mean that the products have microcrystalline regions between 10 and a few hundred nm in size, values of up to at most 50 nm and, more particularly, up to at most 20 nm being preferred. So-called X-ray amorphous silicates such as these, which also dissolve with delay in relation to conventional waterglasses, are described for example in German patent application DE-A-4400024 A1. Compacted amorphous silicates, compounded amorphous silicates and overdried X-ray-amorphous silicates are particularly preferred.
The generally known phosphates may of course also be used as builders providing their use should not be avoided on ecological grounds. The sodium salts of the orthophosphates1 the pyrophosphates and, in particular, the tripolyphosphates are particularly suitable. Their content is generally no more than 25% by weight and preferably no more than 20% by weight, based on the final composition. In some cases, it has been found that, in combination with other builders, tripolyphosphates in particular produce a synergistic improvement in multiple wash cycle performance, even in small quantities of up to at most 10% by weight, based on the final composition.
Useful organic builders are, for example, the polycarboxylic acids usable in the form of their sodium salts, such as citric acid, adipic acid, succinic acid, glutaric acid, tartaric acid, sugar acids, aminocarboxylic acids, nitrilotriacetic acid (NTA), providing its use is not ecologically unsafe, and mixtures thereof. Preferred salts are the salts of the polycarboxylic acids, such as citric acid, adipic acid, succinic acid, glutaric acid, tartaric acid, sugar acids and mixtures thereof. The acids per se may also be used. Besides their building effect, the acids also typically have the property of an acidifying component and, hence, also serve to establish a relatively low and mild pH value in detergents or cleaners. Citric acid, succinic acid, glutaric acid, adipic acid, gluconic acid and mixtures thereof are particularly mentioned in this regard.
Other suitable organic builders are dextrins, for example oligomers or polymers of carbohydrates which may be obtained by partial hydrolysis of starches. The hydrolysis may be carried out by standard methods, for example acid- or enzyme-catalyzed methods. The end products are preferably hydrolysis products with average molecular weights of 400 to 500,000. A polysaccharide with a dextrose equivalent (DE) of 0.5 to 40 and, more particularly, 2 to 30 is preferred, the DE being an accepted measure of the reducing effect of a polysaccharide by comparison with dextrose which has a DE of 100. Both maltodextrins with a DE of 3 to 20 and dry glucose syrups with a DE of 20 to 37 and also so-called yellow dextrins and white dextrins with relatively high molecular weights of 2,000 to 30,000 may be used. A preferred dextrin is described in British patent application 94 19 091 A1. The oxidized derivatives of such dextrins are their reaction products with oxidizing agents which are capable of oxidizing at least one alcohol function of the saccharide ring to the carboxylic acid function. Dextrins thus oxidized and processes for their production are known, for example, from European patent applications EP 0 232 202 A1, EP 0 427 349 A1, EP 0 472 042 A1 and EP 0 542 496 A1 and from International patent applications WO 92/18542, WO 93/08251, WO 93/16110, WO 94/28030, WO 95/07303, WO 95/12619 and WO 95/20608. An oxidized oligosaccharide corresponding to German patent application DE 196 00 018 A1 is also suitable. A product oxidized at C6 of the saccharide ring can be particularly advantageous.
Other suitable co-builders are oxydisuccinates and other derivatives of disuccinates, preferably ethylenediamine disuccinate. The glycerol di-succinates and glycerol trisuccinates described, for example, in U.S. Pat. No. 4,524,009, in U.S. Pat. No. 4,639,325, in European patent application EP 0 150 930 A1 and in Japanese patent application JP 93/339896 are also particularly preferred in this connection. The quantities used in zeolite-containing and/or silicate-containing formulations are from 3 to 15% by weight.
Other useful organic co-builders are, for example, acetylated hydroxycarboxylic acids and salts thereof which may optionally be present in lactone form and which contain at least 4 carbon atoms, at least one hydroxy group and at most two acid groups. Co-builders such as these are described, for example, in International patent application WO 95/20029.
Suitable polymeric polycarboxylates are, for example, the sodium salts of polyacrylic acid or polymethacrylic acid, for example those with a relative molecular weight of 800 to 150,000 (based on acid and measured against polystyrenesulfonic acid). Suitable copolymeric polycarboxylates are, in particular, those of acrylic acid with methacrylic acid and of acrylic acid or methacrylic acid with maleic acid. Acrylic acid/maleic acid copolymers containing 50 to 90% by weight of acrylic acid and 50 to 10% by weight of maleic acid have proved to be particularly suitable. Their relative molecular weight, based on free acids, is generally in the range from 5,000 to 200,000, preferably in the range from 10,000 to 120,000 and more preferably in the range from 50,000 to 100,000 (as measured against polystyrenesulfonic acid). The (co)polymeric polycarboxylates may be used either as powders or as aqueous solutions, 20 to 55% by weight aqueous solutions being preferred. Granular polymers are generally added to basic granules of one or more types in a subsequent step. Also particularly preferred are biodegradable polymers of more than two different monomer units, for example those which contain salts of acrylic acid and maleic acid and vinyl alcohol or vinyl alcohol derivatives as monomers in accordance with DE 43 00 772 A1 or salts of acrylic acid and 2-alkylallyl sulfonic acid and sugar derivatives as monomers in accordance with DE 42 21 381 C2. Other preferred copolymers are those described in German patent applications DE 43 03 320 A1 and DE 44 17 734 A1 which preferably contain acrolein and acrylic acid/acrylic acid salts or acrolein and vinyl acetate as monomers. Other preferred builders are polymeric aminodicarboxylic acids, salts and precursors thereof. Polyaspartic acids and salts and derivatives thereof are particularly preferred.
Other suitable builders are polyacetals which may be obtained by reaction of dialdehydes with polyol carboxylic acids containing 5 to 7 carbon atoms and at least three hydroxyl groups, for example as described in European patent application EP 0 280 223 A1. Preferred polyacetals are obtained from dialdehydes, such as glyoxal, glutaraldehyde, terephthal-aldehyde and mixtures thereof and from polyol carboxylic acids, such as gluconic acid and/or glucoheptonic acid.
In addition, the compositions may contain components with a positive effect on the removability of oil and fats from textiles by washing. Preferred oil- and fat-dissolving components include, for example, nonionic cellulose ethers, such as methyl cellulose and methyl hydroxypropyl cellulose containing 15 to 30% by weight of methoxyl groups and 1 to 15% by weight of hydroxypropoxyl groups, based on the nonionic cellulose ether, and the polymers of phthalic acid and/or terephthalic acid known from the prior art or derivatives thereof, more particularly polymers of ethylene terephthalates and/or polyethylene glycol terephthalates or anionically and/or nonionically modified derivatives thereof. Of these, the sulfonated derivatives of phthalic acid and terephthalic acid polymers are particularly preferred.
Other suitable ingredients of the detergents/cleaning compositions are water-soluble inorganic salts, such as bicarbonates, carbonates, amorphous silicates, normal waterglasses with no pronounced builder properties or mixtures thereof. One particular embodiment is characterized by the use of alkali metal carbonate and/or amorphous alkali metal silicate, above all sodium silicate with a molar Na2O:SiO2 ratio of 1:1 to 1:4.5 and preferably 1:2 to 1:3.5. The sodium carbonate content of the final detergents/cleaning compositions is preferably up to 40% by weight and advantageously from 2 to 35% by weight. The content of sodium silicate (without particular building properties) in the detergents/cleaning compositions is generally up to 10% by weight and preferably between 1 and 8% by weight.
Besides the ingredients mentioned, the detergents/cleaning compositions may contain other known additives, for example salts of polyphosphonic acids, optical brighteners, enzymes, enzyme stabilizers, small quantities of neutral filler salts and dyes and perfumes and the like.
Among the compounds yielding H2O2 in water which serve as bleaching agents, sodium perborate tetrahydrate and sodium perborate monohydrate are particularly important. Other useful bleaching agents are, for example, sodium percarbonate, peroxypyrophosphates, citrate perhydrates and H2O2-yielding peracidic salts or peracids, such as perbenzoates, peroxophthalates, diperazelaic acid, phthaloiminoperacid or diperdodecanedioic acid. The content of peroxy bleaching agents in the detergents/cleaning compositions is preferably 5 to 35% by weight and more preferably up to 30% by weight, perborate monohydrate or percarbonate advantageously being used.
Suitable bleach activators are compounds which form aliphatic peroxocarboxylic acids containing preferably 1 to 10 carbon atoms and more preferably 2 to 4 carbon atoms and/or optionally substituted perbenzoic acid under perhydrolysis conditions. Substances bearing O- and/or N-acyl groups with the number of carbon atoms mentioned and/or optionally substituted benzoyl groups are suitable. Preferred bleach activators are polyacylated alkylenediamines, more particularly tetraacetyl ethylenediamine (TAED), acylated triazine derivatives, more particularly 1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine (DADHT), acylated glycol-urils, more particularly tetraacetyl glycoluril (TAGU), N-acylimides, more particularly N-nonanoyl succinimide (NOSI), acylated phenol sulfonates, more particularly n-nonanoyl or isononanoyloxybenzenesulfonate (n- or iso-NOBS), carboxylic anhydrides, more particularly phthalic anhydride, acylated polyhydric alcohols, more particularly triacetin, ethylene glycol diacetate, 2,5-diacetoxy-2,5-dihydrofuran and the enol esters known from German patent applications DE 196 16 693 A1 and DE 196 16 767 A1, acetylated sorbitol and mannitol and the mixtures thereof (SORMAN) described in European patent application EP 0 525 239 A1, acylated sugar derivatives, more particularly pentaacetyl glucose (PAG), pentaacetyl fructose, tetraacetyl xylose and octaacetyl lactose, and acetylated, optionally N-alkylated glucamine and gluconolactone, and/or N-acylated lactams, for example N-benzoyl caprolactam, which are known from International patent applications WO 94/27970, WO 94/28102, WO 94/28103, WO 95/00626, WO 95/14759 and WO 95/17498. The substituted hydrophilic acyl acetals known from German patent application DE 196 16 769 A1 and the acyl lactams described in German patent application DE 196 16 770 and in International patent application WO 95/14075 are also preferably used. The combinations of conventional bleach activators known from German patent application DE 44 43 177 A1 may also be used. Bleach activators such as these are present in the usual quantities, preferably in quantities of 1% by weight to 10% by weight and more preferably in quantities of 2% by weight to 8% by weight, based on the detergent/cleaning composition as a whole. In addition to or instead of the conventional bleach activators mentioned above, the sulfonimines known from European patents EP 0 446 982 B1 and EP 0 453 003 B1 and/or bleach-boosting transition metal salts or transition metal complexes may also be present as so-called bleach catalysts. Suitable transition metal compounds include, in particular, the manganese-, iron-, cobalt-, ruthenium- or molybdenum-salen complexes known from German patent application DE 195 29 905 A1 and the N-analog compounds thereof known from German patent application DE 196 20 267 A1, the manganese-, iron-, cobalt-, ruthenium- or molybdenum-carbonyl complexes known from German patent application DE 195 36 082 A1, the manganese, iron, cobalt, ruthenium, molybdenum, titanium, vanadium and copper complexes with nitrogen-containing tripod ligands described in German patent application DE 196 05 688, the cobalt-, iron-, copper- and ruthenium-ammine complexes known from German patent application DE 196 20 411 A1, the manganese, copper and cobalt complexes described in German patent application DE 44 16 438 A1, the cobalt complexes described in European patent application EP 0 272 030 A1, the manganese complexes known from European patent application EP 0 693 550 A1, the manganese, iron, cobalt and copper complexes known from European patent EP 0 392 592 A1 and/or the manganese complexes described in European patent EP 0 443 651 B1 or in European patent applications EP 0 458 397 A1, EP 0 458 398 A1, EP 0 549 271 A1, EP 0 549 272 A1, EP 0 544 490 A1 and EP 0 544 519 A1. Combinations of bleach activators and transition metal bleach catalysts are known, for example, from German patent application DE 196 13 103 A1 and from international patent application WO 95/27775. Bleach-boosting transition metal complexes, more particularly with the central atoms Mn, Fe, Co. Cu, Mo. V, Ti and/or Ru, are used in typical quantities, preferably in a quantity of up to 1% by weight, more preferably in a quantity of 0.0025% by weight to 0.25% by weight and most preferably in a quantity of 0.01% by weight to 0.1% by weight, based on the detergent/cleaning composition as a whole.
Suitable enzymes are, in particular, enzymes from the class of hydrolases, such as proteases, esterases, lipases or lipolytic enzymes, amylases, cellulases or other glycosyl hydrolases and mixtures thereof. All these hydrolases contribute to the removal of stains, such as protein-containing, fat-containing or starch-containing stains, and discoloration in the washing process. Cellulases and other glycosyl hydrolases can contribute towards color retention and towards increasing fabric softness by removing pilling and microfibrils. Oxidoreductases may also be used for bleaching and for inhibiting dye transfer. Enzymes obtained from bacterial strains or fungi, such as Bacillus subtilis, Bacillus licheniformis, Streptomyces griseus and Humicola insolens are particularly suitable. Proteases of the subtilisin type are preferably used, proteases obtained from Bacillus lentus being particularly preferred. Of particular interest in this regard are enzyme mixtures, for example of protease and amylase or protease and lipase or lipolytic enzymes or protease and cellulase or of cellulase and lipase or lipolytic enzymes or of protease, amylase and lipase or lipolytic enzymes or protease, lipase or lipolytic enzymes and cellulase, but especially protease- and/or lipase-containing mixtures or mixtures with lipolytic enzymes. Examples of such lipolytic enzymes are the known cutinases. Peroxidases or oxidases have also been successfully used in some cases. Suitable amylases include in particular α-amylases, isoamylases, pullanases and pectinases. Preferred cellulases are cellobio-hydrolases, endoglucanases and β-glucosidases, which are also known as cellobiases, and mixtures thereof. Since the various cellulase types differ in their CMCase and avicelase activities, the desired activities can be established by mixing the cellulases in the appropriate ratios. The enzymes may be adsorbed to supports and/or encapsulated in membrane materials to protect them against premature decomposition. The percentage content of enzymes, enzyme mixtures or enzyme granules may be, for example, about 0.1 to 5% by weight and is preferably from 0.1 to about 2% by weight.
In addition to the monohydric and polyhydric alcohols, the compositions may contain other enzyme stabilizers. For example, 0.5 to 1% by weight of sodium formate may be used. Proteases stabilized with soluble calcium salts and having a calcium content of preferably about 1.2% by weight, based on the enzyme, may also be used. Apart from calcium salts, magnesium salts also serve as stabilizers. However, it is of particular advantage to use boron compounds, for example boric acid, boron oxide, borax and other alkali metal borates, such as the salts of orthoboric acid (H3BO3), metaboric acid (HBO2) and pyroboric acid (tetraboric acid H2B4O7).
The function of redeposition inhibitors is to keep the soil detached from the fibers suspended in the wash liquor and thus to prevent the soil from being re-absorbed by the washing. Suitable redeposition inhibitors are water-soluble, generally organic colloids, for example the water-soluble salts of polymeric carboxylic acids, glue, gelatine, salts of ether carboxylic acids or ether sulfonic acids of starch or cellulose or salts of acidic sulfuric acid esters of cellulose or starch. Water-soluble polyamides containing acidic groups are also suitable for this purpose. Soluble starch preparations and other starch products than those mentioned above, for example degraded starch, aldehyde starches, etc., may also be used. Polyvinyl pyrrolidone is also suitable. However, cellulose ethers, such as carboxymethyl cellulose (sodium salt), methyl cellulose, hydroxyalkyl cellulose, and mixed ethers, such as methyl hydroxyethyl cellulose, methyl hydroxypropyl cellulose, methyl carboxymethyl cellulose and mixtures thereof, and polyvinyl pyrrolidone are also preferably used, for example in quantities of 0.1 to 5% by weight, based on the detergent/cleaning composition.
The detergents/cleaning compositions may contain derivatives of di-aminostilbene disulfonic acid or alkali metal salts thereof as optical brighteners. Suitable optical brighteners are, for example, salts of 4,4′-bis-(2-anilino-4-morpholino-1,3,5-triazinyl-6-amino)-stilbene-2,2′-disulfonic acid or compounds of similar structure which contain a diethanolamino group, a methylamino group and anilino group or a 2-methoxyethylamino group instead of the morpholino group. Brighteners of the substituted diphenyl styryl type, for example alkali metal salts of 4,4′-bis-(2-sulfostyryl)-diphenyl, 4,4′-bis-(4-chloro-3-sulfostyryl)-diphenyl or 4-(4-chlorostyryl)-4′-(2-sulfo-styryl)-diphenyl, may also be present. Mixtures of the brighteners mentioned may also be used. Uniformly white granules are obtained if, in addition to the usual brighteners in the usual quantities, for example between 0.1 and 0.5% by weight and preferably between 0.1 and 0.3% by weight, the detergents/cleaning compositions also contain small quantities, for example 10−6 to 10−3% by weight and preferably around 10−5% by weight, of a blue dye. A particularly preferred dye is Tinolux® (a product of Ciba-Geigy).
Suitable soil repellents are substances which preferably contain ethylene terephthalate and/or polyethylene glycol terephthalate groups, the molar ratio of ethylene terephthalate to polyethylene glycol terephthalate being in the range from 50:50 to 90:10. The molecular weight of the linking polyethylene glycol units is more particularly in the range from 750 to 5,000, i.e. the degree of ethoxylation of the polymers containing poly-ethylene glycol groups may be about 15 to 100. The polymers are distinguished by an average molecular weight of about 5,000 to 200,000 and may have a block structure, but preferably have a random structure. Preferred polymers are those with molar ethylene terephthalate: polyethylene glycol terephthalate ratios of about 65:35 to about 90:10 and preferably in the range from about 70:30 to 80:20. Other preferred polymers are those which contain linking polyethylene glycol units with a molecular weight of 750 to 5,000 and preferably in the range from 1,000 to about 3,000 and which have a molecular weight of the polymer of about 10,000 to about 50,000. Examples of commercially available polymers are the products Milease® T (ICI) or Repelotex® SRP 3 (Rhône-Poulenc).
Wax-like compounds may be used as defoamers in accordance with the present invention. “Wax-like” compounds are understood to be compounds which have a melting point at atmospheric pressure above 25° C. (room temperature), preferably above 50° C. and more preferably above 70° C. The wax-like defoamers are substantially insoluble in water, i.e. their solubility in 100 g of water at 20° C. is less than 0.1% by weight. In principle, any wax-like defoamers known from the prior art may additionally be present. Suitable wax-like compounds are, for example, bisamides, fatty alcohols, fatty acids, carboxylic acid esters of monohydric and polyhydric alcohols and paraffin waxes or mixtures thereof. Alternatively, the silicone compounds known for this purpose may of course also be used.
Suitable paraffin waxes are generally a complex mixture with no clearly defined melting point. For characterization, its melting range is normally determined by differential thermoanalysis (DTA), as described in “The Analyst” 87 (1962), 420, and/or its solidification point is determined. The solidification point is understood to be the temperature at which the paraffin changes from the liquid state into the solid state by slow cooling. Paraffins which are entirely liquid at room temperature, i.e. paraffins with a solidification point below 25° C., are not suitable for use in accordance with the invention. It is possible, for example, to use the paraffin wax mixtures known from EP 0309931 A1 of, for example, 26% by weight to 49% by weight of microcrystalline paraffin wax with a solidification point of 62° C. to 90° C., 20% by weight to 49% by weight of hard paraffin with a solidification point of 42° C. to 56° C. and 2% by weight to 25% by weight of soft paraffin with a solidification point of 35° C. to 40° C. Paraffins or paraffin mixtures which solidify at temperatures of 30° C. to 90° C. are preferably used. It is important in this connection to bear in mind that even paraffin wax mixtures which appear solid at room temperature may contain different amounts of liquid paraffin. In the paraffin waxes suitable for use in accordance with the invention, this liquid component is as small as possible and is preferably absent altogether. Thus, particularly preferred paraffin wax mixtures have a liquid component at 30° C. of less than 10% by weight and, more particularly, from 2% by weight to 5% by weight, a liquid component at 40° C. of less than 30% by weight, preferably from 5% by weight to 25% by weight and more preferably from 5% by weight to 15% by weight, a liquid component at 60° C. of 30% by weight to 60% by weight and preferably 40% by weight to 55% by weight, a liquid component at 80° C. of 80% by weight to 100% by weight and a liquid component at 90° C. of 100% by weight. In particularly preferred paraffin wax mixtures, the temperature at which a liquid component of 100% by weight of the paraffin wax is reached is still below 85° C. and, more particularly, between 75° C. and 82° C. The paraffin waxes may be petrolatum, microcrystalline waxes or hydrogenated or partly hydrogenated paraffin waxes.
Bisamides suitable as defoamers are those derived from saturated fatty acids containing 12 to 22 and preferably 14 to 18 carbon atoms and from alkylenediamines containing 2 to 7 carbon atoms. Suitable fatty acids are lauric acid, myristic acid, stearic acid, arachic acid and behenic acid and the mixtures thereof obtainable from natural fats or hydrogenated oils, such as tallow or hydrogenated palm oil. Suitable diamines are, for example, ethylenediamine, 1,3-propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, p-phenylenediamine and toluylenediamine. Preferred diamines are ethylenediamine and hexamethylenediamine. Particularly preferred bisamides are bis-myristoyl ethylenediamine, bis-palmitoyl ethylenediamine, bis-stearoyl ethylene-diamine and mixtures thereof and the corresponding derivatives of hexamethylenediamine.
Suitable carboxylic acid esters as defoamers are derived from carboxylic acids containing 12 to 28 carbon atoms. The esters in question are, in particular, esters of behenic acid, stearic acid, hydroxystearic acid, oleic acid, palmitic acid, myristic acid and/or lauric acid. The alcohol moiety of the carboxylic acid ester contains a monohydric or polyhydric alcohol containing 1 to 28 carbon atoms in the hydrocarbon chain. Examples of suitable alcohols are behenyl alcohol, arachidyl alcohol, cocoalcohol, 12-hydroxystearyl alcohol, oleyl alcohol and lauryl alcohol and ethylene glycol, glycerol, polyvinylvinyl alcohol, sucrose, erythritol, pentaerythritol, sorbitan and/or sorbitol. Preferred esters are esters of methanol, ethylene glycol, glycerol and sorbitan, the acid moiety of the ester being selected in particular from behenic acid, stearic acid, oleic acid, palmitic acid or myristic acid. Suitable esters of polyhydric alcohols are, for example, xylitol monopalmitate, pentaerythritol monostearate, glycerol monostearate, ethylene glycol monostearate and sorbitan monostearate, sorbitan palmitate, sorbitan monolaurate, sorbitan dilaurate, sorbitan distearate, sorbitan dibehenate, sorbitan dioleate and mixed tallow alkyl sorbitan monoesters and diesters. Suitable glycerol esters are the mono-, di- or triesters of glycerol and the carboxylic acids mentioned, the monoesters and diesters being preferred. Glycerol monostearate, glycerol monooleate, glycerol monopalmitate, glycerol monobehenate and glycerol distearate are examples. Examples of suitable natural esters as defoamers are beeswax, which mainly consists of the esters CH3(CH2)24COO(CH2)27CH3 and CH3(CH2)26COO(CH2)25CH3, and carnauba wax, carnauba wax being a mixture of carnauba acid alkyl esters, often in combination with small amounts of free carnauba acid, other long-chain acids, high molecular weight alcohols and hydrocarbons.
Suitable carboxylic acids as another defoamer compound are, in particular, behenic acid, stearic acid, oleic acid, palmitic acid, myristic acid and lauric acid and the mixtures thereof obtainable from natural fats or optionally hydrogenated oils, such as tallow or hydrogenated palm oil. Saturated fatty acids containing 12 to 22 and, more particularly, 18 to 22 carbon atoms are preferred.
Suitable fatty alcohols as another defoamer compound are the hydrogenated products of the described fatty acids.
Dialkyl ethers may also be present as defoamers. The ethers may have an asymmetrical or symmetrical structure, i.e. they may contain two identical or different alkyl chains, preferably containing 8 to 18 carbon atoms. Typical examples are di-n-octyl ether, di-1-octyl ether and di-n-stearyl ether, dialkyl ethers with a melting point above 25° C. and more particularly above 40° C. being particularly suitable.
Other suitable defoamer compounds are fatty ketones which may be obtained by the relevant methods of preparative organic chemistry. They are produced, for example, from carboxylic acid magnesium salts which are pyrolyzed at temperatures above 300° C. with elimination of carbon dioxide and water, for example in accordance with DE 2553900 OS. Suitable fatty ketones are produced by pyrolysis of the magnesium salts of lauric acid, myristic acid, palmitic aid, palmitoleic acid, stearic acid, oleic acid, elaidic acid, petroselic acid, arachic acid, gadoleic acid, behenic acid or erucic acid.
Other suitable defoamers are fatty acid polyethylene glycol esters which are preferably obtained by the homogeneously base-catalyzed addition of ethylene oxide onto fatty acids. The addition of ethylene oxide onto the fatty acids takes place in particular in the presence of alkanolamines as catalysts. The use of alkanolamines, especially triethanolamine, leads to extremely selective ethoxylation of the fatty acids, particularly where it is desired to produce compounds with a low degree of ethoxylation. Within the group of fatty acid polyethylene glycol esters, those with a melting point above 25° C. and more particularly above 40° C. are preferred.
Within the group of wax-like defoamers, the described paraffin waxes—in a particularly preferred embodiment—are used either on their own as wax-like defoamers or in admixture with one of the other wax-like defoamers, the percentage content of the paraffin waxes in the mixture preferably exceeding 50% by weight, based on the wax-like defoamer mixture. If necessary, the paraffin waxes may be applied to supports. Suitable support materials in the context of the present invention are any known inorganic and/or organic support materials. Examples of typical inorganic support materials are alkali metal carbonates, alumosilicates, water-soluble layer silicates, alkali metal silicates, alkali metal sulfates, for example sodium sulfate, and alkali metal phosphates. The alkali metal silicates are preferably a compound with a molar ratio of alkali metal oxide to SiO2 of 1:1.5 to 1:3.5. The use of silicates such as these results in particularly good particle properties, more particularly high abrasion resistance and at the same time a high dissolving rate in water. Alumosilicates as a support material include, in particular, the zeolites, for example zeolite NaA and NaX. The compounds described as water-soluble layer silicates include, for example, amorphous or crystalline waterglass. Silicates commercially available as Aerosil® or Sipernat® may also be used. Suitable organic carrier materials are, for example, film-forming polymers, for example polyvinyl alcohols, polyvinyl pyrrolidones, poly(meth)acrylates, polycarboxylates, cellulose derivatives and starch. Suitable cellulose ethers are, in particular, alkali metal carboxymethyl cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose and so-called cellulose mixed ethers, for example methyl hydroxyethyl cellulose and methyl hydroxypropyl cellulose, and mixtures thereof. Particularly suitable mixtures are mixtures of sodium carboxymethyl cellulose and methyl cellulose, the carboxymethyl cellulose normally having a degree of substitution of 0.5 to 0.8 carboxymethyl groups per anhydroglucose unit while the methyl cellulose has a degree of substitution of 1.2 to 2 methyl groups per anhydroglucose unit. The mixtures preferably contain alkali metal carboxymethyl cellulose and nonionic cellulose ether in ratios by weight of 80:20 to 40:60 and, more particularly, 75:25 to 50:50. Another suitable support is native starch which is made up of amylose and amylopectin. Native starch is starch obtainable as an extract from natural sources, for example from rice, potatoes, corn and wheat. Native starch is a standard commercial product and is therefore readily available. Suitable support materials are individual compounds or several of the compounds mentioned above selected in particular from the group of alkali metal carbonates, alkali metal sulfates, alkali metal phosphates, zeolites, water-soluble layer silicates, alkali metal silicates, polycarboxylates, cellulose ethers, polyacrylate/polymethacrylate and starch. Mixtures of alkali metal carbonates, more particularly sodium carbonate, alkali metal silicates, more particularly sodium silicate, alkali metal sulfates, more particularly sodium sulfate, and zeolites are particularly suitable.
Suitable silicones in the context of the present invention are typical organopolysiloxanes containing fine-particle silica which, in turn, may even be silanized. Corresponding organopolysiloxanes are described, for example, in European patent application EP 0 496 510 A1. Polydiorgano-siloxanes known from the prior art are particularly preferred. However, siloxane-crosslinked compounds known to the expert as silicone resins may also be used. The polydiorganosiloxanes generally contain fine-particle silica which may even be silanized. Silica-containing dimethyl polysiloxanes are particularly suitable for the purposes of the present invention. The polydiorganosiloxanes advantageously have a Brookfield viscosity at 25° C. of 5000 mPas to 30,000 mPas and, more particularly, 15,000 mPas to 25,000 mPas. The silicones are preferably applied to support materials. Suitable support materials were described above in connection with the paraffins. The support materials are generally present in quantities of 40 to 90% by weight and preferably in quantities of 45 to 75% by weight, based on defoamer.
Suitable perfume oils or perfumes include individual perfume compounds, for example synthetic products of the ester, ether, aldehyde, ketone, alcohol and hydrocarbon type. Perfume compounds of the ester type are, for example, benzyl acetate, phenoxyethyl isobutyrate, p-tert.butyl cyclohexyl acetate, linalyl acetate, dimethyl benzyl carbinyl acetate, phenyl ethyl acetate, linalyl benzoate, benzyl formate, ethyl methyl phenyl glycinate, allyl cyclohexyl propionate, styrallyl propionate and benzyl salicylate. The ethers include, for example, benzyl ethyl ether; the aldehydes include, for example, the linear alkanals containing 8 to 18 carbon atoms, citral, citronellal, citronellyloxyacetaldehyde, cyclamen aldehyde, hydroxycitronellal, lilial and bourgeonal; the ketones include, for example, the ionones, α-isomethyl ionone and methyl cedryl ketone; the alcohols include anethol, citronellol, eugenol, geraniol, linalool, phenyl ethyl alcohol and terpineol and the hydrocarbons include, above all, the terpenes, such as limonene and pinene. However, mixtures of various perfumes which together produce an attractive perfume note are preferably used. Perfume oils such as these may also contain natural perfume mixtures obtainable from vegetable sources, for example pine, citrus, jasmine, patchouli, rose or ylang—ylang oil. Also suitable are clary oil, camomile oil, clove oil, melissa oil, mint oil, cinnamon leaf oil, lime blossom oil, juniper berry oil, vetiver oil, olibanum oil, galbanum oil and ladanum oil and orange blossom oil, neroli oil, orange peel oil and sandalwood oil.
The perfumes may be directly incorporated in the detergents/cleaning compositions according to the invention, although it can also be of advantage to apply the perfumes to supports which strengthen the adherence of the perfume to the washing and which provide the textiles with a long-lasting fragrance through a slower release of the perfume. Suitable support materials are, for example, cyclodextrins, the cyclodextrin/perfume complexes optionally being coated with other auxiliaries.
If desired, the final preparations may also contain inorganic salts as fillers, such as sodium sulfate, for example, which is preferably present in quantities of 0 to 10% by weight and more particularly 1 to 5% by weight, based on the preparation.
Production of the Laundry Detergents, Dishwashing Detergents and Cleaning Compositions
As already mentioned, the preparations obtainable using the surfactant granules according to the invention may be produced and used in the form of powders, extrudates, granules or agglomerates. They may be both heavy-duty and light-duty detergents or detergents for colored fabrics, optionally in the form of compactates or supercompactates. Compositions such as these may be produced by any of the corresponding processes known in the art. They are preferably produced by mixing together various particulate components containing detergent ingredients. The particulate components may be produced by spray drying, simple mixing or complex granulation processes, for example fluidized-bed granulation. In one particularly preferred embodiment, at least one surfactant-containing component is produced by fluidized-bed granulation. In another particularly preferred embodiment, aqueous preparations of the alkali metal silicate and alkali metal carbonate are sprayed in a dryer together with other detergent ingredients, drying optionally being accompanied by granulation.
The dryer into which the aqueous preparation is sprayed can be any type of dryer. In one preferred embodiment of the process, drying is carried out by spray drying in a drying tower. In this case, the aqueous preparations are exposed in known manner to a stream of drying gas in fine-particle form. Applicants describe an embodiment of spray drying using superheated steam in a number of published patents. The operating principle disclosed in those publications is hereby specifically included as part of the disclosure of the present invention. Reference is made in particular to the following publications: DE 40 30 688 A1 and the further developments according to DE 42 04 035 A1; DE42 04 090 A1; DE 42 06 050 A1; DE 42 06 521 A1; DE 42 06 495 A1; DE 42 08 773 A1; DE 42 09 432 A1 and DE 42 34 376 A1. This process was introduced in connection with the production of the defoamer granules.
In another preferred variant, particularly where detergents/cleaning compositions of high bulk density are to be obtained, the mixtures are subsequently subjected to a compacting step, other ingredients being added to the detergents after this compacting step. In one preferred embodiment of the invention, the ingredients are compacted in a press agglomeration process. The press agglomeration process to which the solid premix (dried basic detergent) is subjected may be carried out in various agglomerators. Press agglomeration processes are classified according to the type of agglomerator used. The four most common press agglomeration processes—which are preferred to the purposes of the invention—are extrusion, roll compacting, pelleting and tabletting, so that preferred agglomeration processes for the purposes of the present invention are extrusion, roll compacting, pelleting and tabletting processes.
One feature common to all these processes is that the premix is compacted and plasticized under pressure and the individual particles are pressed against one another with a reduction in porosity and adhere to one another. In all the processes (but with certain limitations in the case of tabletting), the tools may be heated to relatively high temperatures or may be cooled to dissipate the heat generated by shear forces.
In all the processes, one or more binders may be used as (a) compacting auxiliary(ies). However, it must be made clear at this juncture that, basically, several different binders and mixtures of various binders may also be used. A preferred embodiment of the invention is characterized by the use of a binder which is completely in the form of a melt at temperatures of only at most 130° C., preferably at most 100° C. and more preferably up to 90° C. In other words, the binder will be selected according to the process and the process conditions or, alternatively, the process conditions and, in particular, the process temperature will have to be adapted to the binder if it is desired to use a particular binder.
The actual compacting process is preferably carried out at processing temperatures which, at least in the compacting step, at least correspond to the temperature of the softening point if not to the temperature of the melting point of the binder. In one preferred embodiment of the invention, the process temperature is significantly above the melting point or above the temperature at which the binder is present as a melt. In a particularly preferred embodiment, however, the process temperature in the compacting step is no more than 20° C. above the melting temperature or the upper limit to the melting range of the binder. Although, technically, it is quite possible to adjust even higher temperatures, it has been found that a temperature difference in relation to the melting temperature or to the softening temperature of the binder of 20° C. is generally quite sufficient and even higher temperatures do not afford additional advantages. Accordingly it is particularly preferred, above all on energy grounds, to carry out the compacting step above, but as close as possible to, the melting point or rather to the upper temperature limit of the melting range of the binder. Controlling the temperature in this way has the further advantage that even heat-sensitive raw materials, for example peroxy bleaching agents, such as perborate and/or percarbonate, and also enzymes, can be processed increasingly without serious losses of active substance. The possibility of carefully controlling the temperature of the binder, particularly in the crucial compacting step, i.e. between mixing/homogenizing of the premix and shaping, enables the process to be carried out very favorably in terms of energy consumption and with no damaging effects on the heat-sensitive constituents of the premix because the premix is only briefly exposed to the relatively high temperatures. In preferred press agglomeration processes, the working tools of the press agglomerator (the screw(s) of the extruder, the roller(s) of the roll compactor and the pressure roller(s) the pellet press) have a temperature of at most 150° C., preferably of at most 100° C. and, in a particularly preferred embodiment, at most 75° C., the process temperature being 30° C. and, in a particularly preferred embodiment, at most 20° C. above the melting temperature or rather the upper temperature limit to the melting range of the binder. The heat exposure time in the compression zone of the press agglomerators is preferably at most 2 minutes and, more preferably, between 30 seconds and 1 minute.
Preferred binders which may be used either individually or in the form of mixtures with other binders are polyethylene glycols, 1,2-poly-propylene glycols and modified polyethylene glycols and polypropylene glycols. The modified polyalkylene glycols include, in particular, the sulfates and/or the disulfates of polyethylene glycols or polypropylene glycols with a relative molecular weight of 600 to 12,000 and, more particularly, in the range from 1,000 to 4,000. Another group consists of mono- and/or disuccinates of polyalkylene glycols which, in turn, have relative molecular weights of 600 to 6,000 and, preferably, in the range from 1,000 to 4,000. A more detailed description of the modified polyalkylene glycol ethers can be found in the disclosure of International patent application WO 93/02176. In the context of the present invention, polyethylene glycols include polymers which have been produced using C3-5 glycols and also glycerol and mixtures thereof besides ethylene glycol as starting molecules. In addition, they also include ethoxylated derivatives, such as trimethylol propane containing 5 to 30 EO. The polyethylene glycols preferably used may have a linear or branched structure, linear polyethylene glycols being particularly preferred. Particularly preferred polyethylene glycols include those having relative molecular weights in the range from 2,000 to 12,000 and, advantageously, around 4,000. Polyethylene glycols with relative molecular weights below 3,500 and above 5,000 in particular may be used in combination with polyethylene glycols having a relative molecular weight of around 4,000. More than 50% by weight of such combinations may advantageously contain polyethylene glycols with a relative molecular weight of 3,500 to 5,000, based on the total quantity of polyethylene glycols. However, polyethylene glycols which, basically, are present as liquids at room temperature/1 bar pressure, above all polyethylene glycol with a relative molecular weight of 200, 400 and 600, may also be used as binders. However, these basically liquid polyethylene glycols should only be used in the form of a mixture with at least one other binder, this mixture again having to satisfy the requirements according to the invention, i.e. it must have a melting point or softening point at least above 45° C. Other suitable binders are low molecular weight polyvinyl pyrrolidones and derivatives thereof with relative molecular weights of up to at most 30,000. Relative molecular weight ranges of 3,000 to 30,000, for example around 10,000, are preferred. Polyvinyl pyrrolidones are preferably not used as sole binder, but in combination with other binders, more particularly in combination with polyethylene glycols.
Immediately after leaving the production unit, the compacted material preferably has temperatures of not more than 90° C., temperatures of 35 to 85° C. being particularly preferred. It has been found that exit temperatures—above all in the extrusion process—of 40 to 80° C., for example up to 70° C., are particularly advantageous.
In one preferred embodiment of the invention, the process according to the invention is carried out by extrusion as described, for example in European patent EP 0 486 592 B1 or International patent applications WO 93/02176 and WO 94/09111 or WO 98/12299. In this extrusion process, a solid premix is extruded under pressure to form a strand and, after emerging from the multiple-bore extrusion die, the strands are cut into granules of predetermined size by means of a cutting unit. The solid, homogeneous premix contains a plasticizer and/or lubricant of which the effect is to soften the premix under the pressure applied or under the effect of specific energy, so that it can be extruded. Preferred plasticizers and/or lubricants are surfactants and/or polymers. Particulars of the actual extrusion process can be found in the above-cited patents and patent applications to which reference is hereby expressly made. In one preferred embodiment of the invention, the premix is delivered, preferably continuously, to a planetary roll extruder or to a twin-screw extruder with co-rotating or contra-rotating screws, of which the barrel and the extrusion/granulation head can be heated to the predetermined extrusion temperature. Under the shear effect of the extruder screws, the premix is compacted under a pressure of preferably at least 25 bar or—with extremely high throughputs—even lower, depending on the apparatus used, plasticized, extruded in the form of fine strands through the multiple-bore extrusion die in the extruder head and, finally, size-reduced by means of a rotating cutting blade, preferably into substantially spherical or cylindrical granules. The bore diameter of the multiple-bore extrusion die and the length to which the strands are cut are adapted to the selected granule size. In this embodiment, granules are produced in a substantially uniformly predeterminable particle size, the absolute particle sizes being adaptable to the particular application envisaged. In general, particle diameters of up to at most 0.8 cm are preferred. Important embodiments provide for the production of uniform granules in the millimeter range, for example in the range from 0.5 to 5 mm and more particularly in the range from about 0.8 to 3 mm. In one important embodiment, the length-to-diameter ratio of the primary granules is in the range from about 1:1 to about 3:1. In another preferred embodiment, the still plastic primary granules are subjected to another shaping process step in which edges present on the crude extrudate are rounded off so that, ultimately, spherical or substantially spherical extrudate granules can be obtained. If desired, small quantities of drying powder, for example zeolite powder, such as zeolite NaA powder, can be used in this step. This shaping step may be carried out in commercially available spheronizing machines. It is important in this regard to ensure that only small quantities of fines are formed in this stage. According to the present invention, drying—which is described as a preferred embodiment in the prior art documents cited above—may be carried out in a subsequent step but is not absolutely essential. It may even be preferred not to carry out drying after the compacting step. Alternatively, extrusion/compression steps may also be carried out in low-pressure extruders, in a Kahl press (manufacturer: Amandus Kahl) or in a so-called Bextruder (manufacturer: Bepex). In one particularly preferred embodiment of the invention, the temperature prevailing in the transition section of the screw, the pre-distributor and the extrusion die is controlled in such a way that the melting temperature of the binder or rather the upper limit to the melting range of the binder is at least reached and preferably exceeded. The temperature exposure time in the compression section of the extruder is preferably less than 2 minutes and, more particularly, between 30 seconds and 1 minute.
The detergents according to the invention may also be produced by roll compacting. In this variant, the premix is introduced between two rollers—either smooth or provided with depressions of defined shape—and rolled under pressure between the two rollers to form a sheet-like compactate. The rollers exert a high linear pressure on the premix and may be additionally heated or cooled as required. Where smooth rollers are used, smooth untextured compactate sheets are obtained. By contrast, where textured rollers are used, correspondingly textured compactates, in which for example certain shapes can be imposed in advance on the subsequent detergent particles, can be produced. The sheet-like compactate is then broken up into smaller pieces by a chopping and size-reducing process and can thus be processed to granules which can be further refined and, more particularly, converted into a substantially spherical shape by further surface treatment processes known per se. In roll compacting, too, the temperature of the pressing tools, i.e. the rollers, is preferably at most 150° C., more preferably at most 100° C. and most preferably at most 75° C. Particularly preferred production processes based on roll compacting are carried out at temperatures 10° C. and, in particular, at most 5° C. above the melting temperature of the binder or the upper temperature limit of the melting range of the binder. The temperature exposure time in the compression section of the rollers—either smooth or provided with depressions of defined shape—is preferably at most 2 minutes and, more particularly, between 30 seconds and 1 minute.
The detergents according to the invention may also be produced by pelleting. In this process, the premix is applied to a perforated surface and is forced through the perforations and at the same time plasticized by a pressure roller. In conventional pellet presses, the premix is compacted under pressure, plasticized, forced through a perforated surface in the form of fine strands by means of a rotating roller and, finally, is size-reduced to granules by a cutting unit. The pressure roller and the perforated die may assume many different forms. For example, flat perforated plates are used, as are concave or convex ring dies through which the material is pressed by one or more pressure rollers. In perforated-plate presses, the pressure rollers may also be conical in shape. In ring die presses, the dies and pressure rollers may rotate in the same direction or in opposite directions. A press suitable for carrying out the process according to the invention is described, for example, in DE 38 16 842 A1. The ring die press disclosed in this document consists of a rotating ring die permeated by pressure bores and at least one pressure roller operatively connected to the inner surface thereof which presses the material delivered to the die space through the pressure bores into a discharge unit. The ring die and pressure roller are designed to be driven in the same direction which reduces the shear load applied to the premix and hence the increase in temperature which it undergoes. However, the pelleting process may of course also be carried out with heatable or coolable rollers to enable the premix to be adjusted to a required temperature. In pelleting, too, the temperature of the pressing tools, i.e. the pressure rollers, is preferably at most 150° C., more preferably at most 100° C. and most preferably at most 75° C. Particularly preferred production processes based on pelleting are carried out at temperatures 10° C. and, in particular, at most 5° C. above the melting temperature of the binder or the upper temperature limit of the melting range of the binder.
The production of shaped bodies, preferably those in tablet form, is generally carried out by tabletting or press agglomeration. The particulate press agglomerates obtained may either be directly used as detergents or may be after treated beforehand by conventional methods. Conventional after treatments include, for example, powdering with fine-particle detergent ingredients which, in general, produces a further increase in bulk density. However, another preferred after treatment is the procedure according to German patent applications DE 195 24 287 A1 and DE 195 47 457 A1, according to which dust-like or at least fine-particle ingredients (so-called fine components) are bonded to the particulate end products produced in accordance with the invention which serve as core. This results in the formation of detergents which contain these so-called fine components as an outer shell. Advantageously, this is again done by melt agglomeration. On the subject of the melt agglomeration of fine components, reference is specifically made to the disclosure of German patent applications DE-A-195 24 287 and DE-A-195 47 457. In the preferred embodiment of the invention, the solid detergents are present in tablet form, the tablets preferably having rounded corners and edges, above all in the interests of safer storage and transportation. The base of the tablets may be, for example, circular or rectangular in shape. Multilayer tablets, particularly tablets containing two or three layers which may even have different colors, are particularly preferred. Blue-white or green-white or blue-green-white tablets are particularly preferred. The tablets may also have compressed and non-compressed parts. Tablets with a particularly advantageous dissolving rate are obtained if, before compression, the granular constituents contain less than 20% by weight and preferably less than 10% by weight of particles outside the 0.02 to 6 mm diameter range. A particle size distribution of 0.05 to 2.0 mm is preferred, a particle size distribution of 0.2 to 1.0 mm being particularly preferred.
100 g of cellulose (Technocel® 150) were mixed with 200 g of protein fatty acid condensate (Lamepon® SCE-B, 95% by weight powder, Cognis Deutschland GmbH/DE) and the resulting mixture was compacted in a gear roller mill. A 1.2–1.6 mm sieve fraction was then removed.
1,000 g of cellulose (Technocel® 150) were mixed in a mixer with 300 g of protein fatty acid condensate (Lamepon® SCE-B), 200 g of coconut alkyl oligoglucoside (Glucopon® 600 CSUP, 50% by weight water-containing paste, Cognis Deutschland/DE) and 150 g of a polyethylene glycol wax with an average molecular weight of 4,000 and the water content of the resulting mixture was reduced to 12% by weight by drying. The mixture was then extruded through a multiple bore die (bore diameter: 2 mm) at 45° C. The crude product was size-reduced and a 1.2–1.6 mm sieve fraction was removed.
100 g of cellulose (Technocel® 150) were mixed with 100 g of protein fatty acid condensate (Lamepon® SCE-B) and 20 g of coconut alkyl sulfate sodium salt (Sulfopon® 1218 G, residual water content 5% by weight, Cognis Deutschland GmbH/DE) and the resulting mixture was compacted in a gear roller mill. A 1.2–1.6 mm sieve fraction was then removed.
Surfactant granules consisting of 50% by weight of protein fatty acid condensate (Lamepon® SCE-B), 5% by weight of coconut alkyl sulfate sodium salt, 5% by weight of soda, 10% by weight of sodium silicate and 30% by weight of sodium sulfate; sieve fraction 1.2–1.6 mm.
Surfactant granules consisting of 95% by weight of protein fatty acid condensate (Lamepon® SCE-B); 1.2–1.6 mm sieve fraction.
Performance test. A quantity of the granules corresponding to 10 g of surfactant was introduced into 1 liter of continuously stirred water (15° C.). The solution was passed through a sieve (mesh width 0.2 mm) after 30 s (T1), 60 s (T2) and 180 s (T3). The filter residue was briefly washed with acetone, dried and then weighed. The results are set out in Table 1.
| Number | Date | Country | Kind |
|---|---|---|---|
| 199 56 803 | Nov 1999 | DE | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP00/11339 | 11/16/2000 | WO | 00 | 8/28/2002 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO01/38481 | 5/31/2001 | WO | A |
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| 40 30 688 | Sep 1990 | DE |
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| 42 09 432 | Mar 1992 | DE |
| 42 21 381 | Jul 1992 | DE |
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| 43 00 772 | Jan 1993 | DE |
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| 44 00 024 | Jan 1994 | DE |
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| 195 44 453 | Nov 1995 | DE |
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| 196 00 018 | Jan 1996 | DE |
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| 196 16 693 | Apr 1996 | DE |
| 196 16 767 | Apr 1996 | DE |
| 196 16 769 | Apr 1996 | DE |
| 196 16 770 | Apr 1996 | DE |
| 196 20 411 | Apr 1996 | DE |
| 196 20 267 | May 1996 | DE |
| 197 09 991 | Mar 1997 | DE |
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| 0 150 930 | Jan 1985 | EP |
| 0 272 030 | Dec 1987 | EP |
| 0 392 592 | Apr 1990 | EP |
| 0 427 349 | Nov 1990 | EP |
| 0 443 651 | Feb 1991 | EP |
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| 0 458 398 | May 1991 | EP |
| 0 525 239 | Jul 1991 | EP |
| 0 472 042 | Aug 1991 | EP |
| 0 496 510 | Jan 1992 | EP |
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| 0 549 272 | Dec 1992 | EP |
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