CA2308910A1 - A process for the production of surfactant granules - Google Patents

Abstract

The invention relates to a process for the production of surfactant granules containing nonionic surfactants in which A) in a first process step, sugar surfactants are processed in the presence of water-soluble carrier materials to form a compound and B) the compounds obtained in A) are mixed with a non-aqueous solvent and the resulting mixture and optionally other detergent ingredients are granulated by methods known per se.
The granules produced are readily soluble and show such favorable flow properties that there is no need for a concluding drying step.

Description

A Process for the Production of Surfactant Granules Field of the Invention This invention relates to a two-stage process for the production of surfactant granules containing nonionic surfactants.
Background of the Invention Compacted or highly concentrated detergent powders or tablets represent a substantial percentage of commercially available detergents.
Such detergents are generally not obtained by a spray drying process, but rather by mixing, granulation and compacting processes in which high temperatures are avoided. On account of the relatively low temperatures, the removal of water introduced by the starting materials is relatively laborious. In many cases, a drying step has to be carried out on completion of the granulation process.
Another problem lies in the poor solubility of the relatively heavily compacted particles. This problem is often encountered in particular with formulations containing a high percentage of alkoxylated fatty alcohols. An improvement in solubility can be achieved by incorporating alkyl poly-glycosides in the granules. However, the incorporation of the alkyl poly-glycosides is problematical because they cannot be processed by spray drying processes and the resulting particles are extremely tacky. In addition, the use of alkyl polyglycosides as a paste in the granulation process leads to extremely tacky products, particularly in the case of granules with a high alkyl benzenesulfonate content.
The processed polyglycoside pastes have a water content of around 50% by weight from their production. Accordingly, to produce dry, i.e. non tacky, and dust-free granules, the water has to be almost completely removed.
The removal of water often leads to granules with a variable water content. If the granules are to be further processed to tablets which are .. CA 02308910 2000-OS-19 expected to show rapid and constant solubility in water, the use of granules with a variable water content can lead to tablets with variable dissolving rates.
The production of surfactant granules for use in detergents is known from the prior art. Thus, EP-A-0 859 048 describes a process for the production of surfactant granules with bulk densities above 600 gll by granulating a surfactant preparation, in which solutions of alkyl benzene-sulfonate andlor alkyl polyglycoside surfactants and carrier materials in a non-surfactant solvent are simultaneously sprayed through one and the same nozzle and dried in conventional dryers, preferably in a fluidized bed dryer or in a ring mixer dryer. The carrier materials used are polycarboxy-lates and inorganic carriers, more particularly amorphous silicates.
International patent application WO 97103165 describes a process for the production of sugar surfactant granules, i.e. granules containing alkyl andlor alkenyl oligoglycosides andlor fatty acid-N-alkyl poly hydroxyalkylamides. In the described process, water-containing pastes of the components mentioned are granulated in the presence of zeolites andlor waterglasses and dried either at the same time or in a subsequent step. The document in question also gives an example of the granulation of a water-free mixture of an alkyl oligoglycoside and an alkoxylated fatty alcohol.
International patent application WO 97!09415 discloses a process for the production of a non-spray-dried particulate surfactant composition which has a bulk density of at least 600 gll and which contains a polymeric builder component andlor a soil-release polymer. The granulation liquid and solid constituents are mixed in a granulator and the polymer is added in admixture with a non-aqueous diluent during the granulation step. An ethoxylated nonionic surfactant is preferably used as the non-aqueous diluent.
International patent application WO 97!02338 discloses a process _ CA 02308910 2000-OS-19 for the production of particulate surfactant compositions with a bulk density below 700 gll. To produce the surfactant composition disclosed in this document, a particulate starting material which contains at least 10% by weight of a component with a bulk density of not more than 600 gll and which is not a surfactant compound is mixed with a liquid binder in a granulator and then granulated. The particulate starting material contains a builder. Surfactant or a surfactant precursor is present in the particulate starting material andlor in the binder.
International patent application WO 97!22685 discloses a process for the production of particulate detergent compositions with bulk densities of 300 to 1300 gll. In the process disclosed in this document, particulate starting material is mixed with a liquid binder and partly granulated. The partly granulated mixture is transferred to a less shear-intensive granulator, more liquid binder is added and the granulation process is continued until a particulate powder with the required bulk density is obtained. Water, anionic surfactant, nonionic surfactant or mixtures thereof may be used as the liquid binder.
European patent application 0 799 884 describes a process for the production of free-flowing particulate surfactant compositions containing alkyl polyglycosides in which a concluding drying step is said to be unnecessary. To carry out the described process, a mixture of a water-containing alkyl polyglycoside paste, an ethoxylated nonionic surfactant and a solid water-soluble inorganic salt is initially prepared. The mixture obtained separates into an organic phase and a water-rich phase, the organic phase containing alkyl polyglycoside, ethoxylated nonionic surfac-tant and water being separated off. The percentages of the individual components in the first step is selected so that the ratio of alkyl polyglyco-side to ethoxylated nonionic surfactant in the organic phase is in the range from 35:65 to 65:35 and the ratio of ethoxylated nonionic surfactant to the total quantity of water is in the range from 90:10 to 60:10. To produce the surfactant compositions, the mixture obtained and, optionally, other surfactants are mixed with one or more particulate carrier materials and the resulting mixture is processed in a conventional high-speed mixer or granulator to form a particulate product.
The processes described above have the disadvantage that they are either very complicated to carry out or lead to non-free-flowing products with - in some cases - poor solubility.
The problem addressed by the present invention was to provide a process for the production of surfactant granules which would not be attended by the disadvantages mentioned above. More particularly, the present invention set out to provide a process which would give granules characterized by good and constant solubility. In addition, the granules obtained would show such favorable free flow behavior that there would be no need for an additional drying step.
Description of the Invention It has now surprisingly been found that, if - in a two-stage granulation process - a fine-particle compound of alkyl polyglycoside on a suitable carrier is initially prepared and is then granulated in a second step in the presence of a liquid surfactant and optionally other detergent ingredients, free-flowing granules with good dissolvability are obtained without a drying step.
Accordingly, the present invention relates to a process for the production of surfactant granules containing nonionic surfactants and other detergent ingredients, characterized in that A) in a first process step, sugar surfactants are processed in the presence of water-soluble carrier materials to form a compound and B) the compounds obtained in A) are mixed with a non-aqueous solvent and the resulting mixture and optionally other detergent ingredients are granulated by methods known per se.
The sugar surfactants suitable for use in process step A) may be selected in particular from alkyl and alkenyl oligoglycosides and poly-hydroxyfatty acid amides.
The alkyl and alkenyl oligoglycosides correspond to the following general formula:

R' O(G)x (I) in which R' is a primary, linear or methyl-branched, more particularly 2-methyl-branched, alkyl or alkenyl group containing 8 to 22 and preferably 12 to 18 carbon atoms and G stands for a glycose unit containing 5 or 6 carbon atoms, preferably glucose. The degree of oligomerization x, which indicates the distribution of monoglycosides and oligoglycosides, is a number of 1 to 10; x preferably has a value of 1.2 to 1.4.
Suitable polyhydroxyfatty acid amides are those corresponding to formula (II):

R2-CO-N-[Z] (I I) in which RICO is an aliphatic acyl group containing 6 to 22 carbon atoms, R3 is hydrogen, an alkyl or hydroxyalkyl group containing 1 to 4 carbon atoms and [Z] is a linear or branched polyhydroxyalkyl group containing 3 to 10 carbon atoms and 3 to 10 hydroxyl groups.
The polyhydroxyfatty acid amides are known substances which may normally be obtained by reductive amination of a reducing sugar with ammonia, an alkylamine or an alkanolamine and subsequent acylation with a fatty acid, a fatty acid alkyl ester or a fatty acid chloride. Particulars of processes for their production can be found in US-A-1,985,424, US-A-2,016,962 and US-A-2,703,798 and in International patent application WO-A-92106984. The polyhydroxyfatty acid amides are preferably derived from reducing sugars containing 5 or 6 carbon atoms, more particularly glucose.
The sugar surfactants may be used in the form of the aqueous solutions obtained from the production process. They may also be used in the form of granules, of which the production is described in WO 97103165, or in the form of steam-dried products which may be obtained by the process described in WO 95114519.
The carrier materials used in the first step of the process are preferably waterglass or water-soluble detergent builders such as, for example, layer silicates or organic polymers.
Suitable waterglasses are amorphous sodium silicates with an Na20:Si02 ratio (modulus) of 1:2 to 1:3.3, preferably 1:2 to 1:2.8 and more preferably 1:2 to 1:2.6. 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. However, 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-44 00 024. Compacted amorphous silicates, compounded amorphous silicates and overdried X-ray-amorphous silicates are particularly preferred.

Suitable, crystalline layer-form sodium silicates correspond to the general formula NaMSiX02X+~A y H20, 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-A-0 164 514. 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 ~- and 8-sodium disilicates Na2Si205A y H20 are particularly preferred, ~i-sodium disilicate being obtainable, for example, by the process described in International patent application WO-A-91108171.
Useful organic carrier materials are, for example, the polycarboxylic acids usable, for example, in the form of their sodium salts, polycarboxylic acids in this context being understood to be carboxylic acids which bear more than one acid function. Examples of such carboxylic acids are citric acid, adipic acid, succinic acid, glutaric acid, malic acid, tartaric acid, malefic acid, fumaric acid, sugar acids, aminocarboxylic acids, nitrilotriacetic acid (NTA), providing their 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 builder 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. Citric acid, succinic acid, glutaric acid, adipic acid, gluconic acid and mixtures thereof are particularly mentioned in this regard.
Other suitable builders are polymeric polycarboxylates such as, for example, the alkali metal salts of polyacrylic or polymethacrylic acid, for example those with a relative molecular weight of 500 to 70,000 glmole.
The molecular weights mentioned in this specification for polymeric polycarboxylates are weight-average molecular weights MW of the particular acid form which, basically, were determined by gel permeation chromatography (GPC) using a UV detector. The measurement was carried out against an external polyacrylic acid standard which provides realistic molecular weight values by virtue of its structural similarity to the polymers investigated. These values differ distinctly from the molecular weights measured against polystyrene sulfonic acids as standard. The molecular weights measured against polystyrene sulfonic acids are generally higher than the molecular weights mentioned in this specification.
Particularly suitable polymers are polyacrylates which preferably have a molecular weight of 2,000 to 20,000 glmole. By virtue of their superior solubility, preferred representatives of this group are the short chain polyacrylates which have molecular weights of 2,000 to 10,000 g/mole and, more particularly, 3,000 to 5,000 glmole.
Also suitable are copolymeric polycarboxylates, particularly those of acrylic acid with methacrylic acid and those of acrylic acid or methacrylic acid with malefic acid. Acrylic acid/maleic acid copolymers containing 50 to 90% by weight of acrylic acid and 50 to 10% by weight of malefic acid have proved to be particularly suitable. Their relative molecular weights, based on the free acids, are generally in the range from 2,000 to 70,000 g/mole, preferably in the range from 20,000 to 50,000 g/mole and more preferably in the range from 30,000 to 40,000 g/mole.
The (co)polymeric polycarboxylates may be used either in powder form or in the form of an aqueous solution. The content of (co)polymeric polycarboxylates in the detergent is preferably from 0.5 to 20% by weight and more preferably from 3 to 10% by weight.
In order to improve solubility in water, the polymers may also contain allyl sulfonic acids, such as allyloxybenzene sulfonic acid and methallyl sulfonic acid (cf. for example EP-B-727 448), as monomer.
Other particularly preferred polymers are biodegradable polymers of more than two different monomer units, for example those which contain salts of acrylic acid and malefic acid and vinyl alcohol or vinyl alcohol derivatives as monomers in accordance with DE-A-43 00 772 or those which contain salts of acrylic acid and 2-alkylallyl sulfonic acid and sugar derivatives as monomers in accordance with DE-C-42 21 381.
Other preferred copolymers are those which are described in German patent applications DE-A-43 03 320 and DE-A-44 17 734 and which preferably contain acrolein and acrylic acid/acrylic acid salts or acrolein and vinyl acetate as monomers.
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 glmole. 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 sirups 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 glmole may be used. A preferred dextrin is described in British patent application 94 19 091.
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-A-0 232 202, EP-A-0 427 349, EP-A-0 472 042 and EP-A-0 542 496 and from International patent applications WO 92/18542, WO 93108251, WO 93/16110, WO 94128030, WO 95107303, WO 95112619 and WO 95120608. An oxidized oligosaccharide corresponding to German patent application DE-A-196 00 018 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. Ethylenediamine-5 N,N'-disuccinate (EDDS), of which the synthesis is described for example in US 3,158,615 is preferably used in the form of its sodium or magnesium salts. The glycerol disuccinates and glycerol trisuccinates described, for example, in US 4,524,009 and US 4,639,325, in European patent application EP-A-0 150 930 and in Japanese patent application JP
10 931339896 are also 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 95120029.
Other suitable carrier materials are oxidation products of polyglucosans containing carboxyl groups andlor water-soluble salts thereof which are described, for example, in International patent application WO-A-93!08251 or which the production is described, for example, in International patent application WO-A-93116110. Oxidized oligosaccharides according to German patent application DE 196 00 018 are also suitable.
Other preferred builders are polymeric aminodicarboxylic acids, salts or precursors thereof. Particular preference is attributed to polyaspartic acids or salts and derivatives thereof which, according to German patent application DE-A-195 40 086, are also said to have a bleach-stabilizing effect in addition to their co-builder properties.
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 3 hydroxyl groups, for example as described in European patent application EP-A-0 280 223. Preferred polyacetals are obtained from dialdehydes, such as glyoxal, glutaraldehyde, terephthal-aldehyde and mixtures thereof and from polyol carboxylic acids, such as gluconic acid andlor glucoheptonic acid.
Another class of substances with co-builder properties are the phosphonates, more particularly hydroxyalkane and aminoalkane phos-phonates. Among the hydroxyalkane phosphonates, 1-hydroxyethane-1,1-diphosphonate (HEDP) is particularly important as a co-builder. It is preferably used in the form of the sodium salt, the disodium salt showing a neutral reaction and the tetrasodium salt an alkaline reaction (pH 9).
Preferred aminoalkane phosphonates are ethylenediamine tetramethylene phosphonate (EDTMP), diethylenetriamine pentamethylenephosphonate (DTPMP) and higher homologs thereof. They are preferably used in the form of the neutrally reacting sodium salts, for example as the hexasodium salt of EDTMP or as the hepta- and octasodium salts of DTPMP. Of the phosphonates, HEDP is preferably used as a builder. In addition, the aminoalkane phosphonates have a pronounced heavy metal binding capacity. Accordingly, it can be of advantage, particularly where the detergents also contain bleach, to use aminoalkane phosphonates, more particularly DTPMP, or mixtures of the phosphonates mentioned.
In addition, any compounds capable of forming complexes with alkaline earth metal ions may be used as co-builders.
Compounds with a particle size of preferably at most 1 mm, more preferably at most 0.8 mm and most preferably at most 0.4 mm are obtained in the first step A) of the process. If coarser particles are formed, they may be ground and reduced to the required particle size in a mill following the first process step.
The first step of the process is preferably carried out in a conventional fluidized bed granulator andlor steam dryer.
In the second step B) of the process, the compounds obtained in step A) are mixed with a non-aqueous solvent and the resulting mixture and optionally other detergent ingredients are granulated by methods known per se.
Preferred non-aqueous solvents are compounds which are liquid at a temperature of about 80°C, preferably at a temperature of 40°C
and more preferably at room temperature and which additionally have detersive properties. Liquid nonionic surfactants are particularly preferred.
It has proved to be suitable for carrying out the process according to the invention initially to dissolve or suspend the compounds in the liquid nonionic surfactants. Other ingredients normally present in detergent granules may also be added at this stage.
The liquid nonionic surfactant preferably used as solvent in step B) is preferably a fatty alcohol alkoxylate. Particularly suitable nonionic surfactants are alkoxylated, advantageously ethoxylated, more especially primary alcohols preferably containing 8 to 18 carbon atoms and, on average, 1 to 12 moles of ethylene oxide (EO) per mole of alcohol, in which the alcohol group may be linear or, preferably, methyl-branched in the 2-position or may contain linear and methyl-branched groups in the form of the mixtures typically present in oxoalcohol groups. However, alcohol ethoxylates containing linear groups of alcohols of native origin with 12 to 18 carbon atoms, for example coconut, palm, tallow or oleyl alcohol, and on average 2 to 8 EO per mole of alcohol are particularly preferred.
Preferred ethoxylated alcohols include, for example, C~2_~4 alcohols containing 3 EO or 4 EO, C9_» alcohols containing 7 EO, C~3-~5 alcohols containing 3 EO, 5 EO, 7 EO or 8 EO, C~2_~$ alcohols containing 3 EO, 5 EO or 7 EO and mixtures thereof, such as mixtures of C~z_~a alcohol containing 3 EO and C~2_~a alcohol containing 7 EO. The degrees of ethoxylation mentioned represent statistical mean values which, for a special product, can be a whole number or a broken number. Preferred alcohol ethoxylates have a narrow homolog distribution (narrow range ethoxylates, NRE). In addition to these nonionic surfactants, fatty alcohols containing more than 12 EO may also be used, examples including (tallow) fatty alcohols containing 14 EO, 16 EO, 20 EO, 25 EO, 30 EO or 40 EO.
The granulation process may be carried out in a number of machines typically used in the detergent industry. For example, the spheronizers commonly used in the pharmaceutical industry may be used.
In machines such as these, the residence time of the granules is normally less than 20 seconds. Conventional mixers and mixerlgranulators may also be used for the granulation process. Suitable mixers are both high-shear mixers and also normal mixers operating at relatively low rotational speeds. Suitable mixers are, for example, Series R or RV Eirich~ mixers (trademarks of Maschinenfabrik Gustav Eirich, Hardheim), the Schugi~
Flexomix, the Fukae~ FS-G mixers (trademarks of Fukae Powtech, Kogyo Co., Japan), Lodige~ FM, KM and CB mixers (trademarks of Lodige Maschinenbau GmbH, Paderborn) and Series T or K-T Drais~ mixers (trademarks of Drais-Werke GmbH, Mannheim). In all these mixers and spheronizers, the particles are converted into granules by liquid bridge binding of the non-aqueous binders. The residence times of the granules in the mixers is less than 60 seconds, the residence time also depending on the rotational speed of the mixer. The residence times are shorter, the faster the rotational speed of the mixer. The residence times of the granules in mixerslspheronizers are preferably less than 1 minute and more preferably under 15 seconds. In low-speed mixers, for example Lodige KM mixers, the residence times are up to 20 minutes, residence times of less than 10 minutes being preferred in the interests of process economy.
In the press agglomeration process, the surfactant-containing granules are compacted under pressure and under the effect of shear forces and, at the same time, homogenized and are then discharged from the machines via a shapinglforming stage. Industrially the most important press agglomeration processes are extrusion, roller compacting, pelleting and tabletting. Press agglomeration processes preferably used in accordance with the present invention for producing the surfactant-containing granules are extrusion, roller compacting and pelleting.
The product obtained on completion of the granulation process is dry and does not have to be subjected to another drying step.
In order further to improve their processability and "dosability", the granules obtained may be powdered with an oil absorption component. As a result of this concluding powdering step using a fine-particle component, the liquids are fixed to the surface of the granules so that the granules are unable to form lumps in storage. The oil absorption component should have an oil absorption capacity of at least 20 g1100 g, preferably of at least 50 g1100 g, more preferably of at least 80 g1100 g, more preferably of at least 120 81100 g and, in one particular embodiment, of at least 140 81100 g.
The oil absorption capacity is a physical property of a substance which can be measured by standardized methods. For example British Standards BS1795 and BS3483:Part B7:1982, which both refer to ISO
787!5, are available. In these test methods, a weighed sample of the particular substance is applied to a dish and refined linseed oil (density:
0.93 gcm)3) is added dropwise from a burette. After each addition, the powder is intensively mixed with the oil using a spatula, the addition of oil being continued until a paste of flexible consistency is obtained. This paste should flow without crumbling. Now, the oil absorption capacity is the quantity of oil added dropwise, based on 100 g of absorbent, and is expressed in m1/100 g or 81100 g, conversions via the density of the linseed oil readily being possible.
The oil absorption component preferably has a small mean particle ' CA 02308910 2000-OS-19 size because the active surface increases with decreasing particle size.
Preferred detergent tablets contain a component with an oil absorption capacity of at least 20 g1100 g which has a mean particle size below 50 Nm, preferably below 20 Nm and more preferably below 10 Nm.
5 The oil absorption component may be selected from a number of substances. There are many inorganic and organic substances which have a sufficiently large oil absorption capacity. Fine-particle materials obtained by precipitation are mentioned by way of example in this regard. Suitable oil absorption components are, for example, silicates, alumosilicates, 10 calcium silicates, magnesium silicates and calcium carbonate. However, kieselghur (diatomaceous earth) and fine-particle cellulose fibers or derivatives thereof may also be used in accordance with the invention.
Preferred detergent tablets are characterized in that the component present in them with an oil absorption capacity of at least 20 g1100 g is 15 selected from silicates and/or alumosilicates, more particularly from the group of silicas andlor zeolites. These include, for example, fine-particle zeolites and also pyrogenic silicas (Aerosil~) or precipitated silicas.
Other surfactants, more particularly anionic surfactants, and builders may be incorporated in the surfactant granules as additional components.
In one preferred embodiment, the other components are incorpo-rated in the form of a spray-dried powder in the second step of the process.
Temperature-sensitive or water-sensitive components may be separately added.
Suitable builders are any builders suitable for detergents which have a sufficiently large inner surface to be able to absorb the nonionic surfactant. Examples of such builders are zeolites, amorphous silicates, soda, phosphates and mixtures thereof, zeolite being preferred.
The zeolite used may be, for example, finely crystalline synthetic zeolite containing bound water, such as zeolite A, zeolite P and mixtures of A and P. An example of a commercially available zeolite P is zeolite MAP~ (a Crosfield product).
Zeolites of the faujasite type are mentioned as other preferred and particularly suitable zeolites. Together with zeolites X and Y, the mineral faujasite belongs to the faujasite types within zeolite structure group 4 which is characterized by the double 6-membered ring subunit D6R (cf.
Donald W. Breck: "Zeolite Molecular Sieves", John Wiley & Sons, New York, London, Sydney, Toronto, 1974, page 92). Besides the faujasite types mentioned, the minerals chabasite and gmelinite and the synthetic zeolites R (chabasite type), S (gmelinite type), L and ZK-5 belong to zeolite structure group 4. The last two of these synthetic zeolites do not have any mineral analogs.
Faujasite zeolites are made up of ~i-cages tetrahedrally linked by D6R subunits, the ~i-cages being arranged similarly to the carbon atoms in diamond. The three-dimensional framework of the faujasite zeolites used in the process according to the invention has pores 2.2 and 7.4 A in size.
In addition, the elementary cell contains eight cavities each ca. 13 A in diameter and may be described by the formula Na86[(A102)as(Si02)~os] ~ 264 H20. The framework of the zeolite X contains a void volume of around 50%, based on the dehydrated crystal, which represents the largest empty space of all known zeolites (zeolite Y: ca. 48% void volume, faujasite: ca.
47% void volume). (All data from: Donald W. Breck: "Zeolite Molecular Sieves", John Wiley & Sons, New York, London, Sydney, Toronto, 1974, pages 145, 176, 177).
In the context of the present invention, the expression "faujasite zeolite" characterizes all three zeolites which form the faujasite subgroup of zeolite structure group 4. According to the invention, therefore, zeolite Y
and faujasite and mixtures of these compounds may also be used in addition to zeolite X although pure zeolite X is preferred. Mixtures or co-crystallizates of faujasite zeolites with other zeolites, which do not necessarily have to belong to zeolite structure group 4, may also be used in accordance with the invention, the advantages of the process according to the invention coming to light particularly clearly when at least 50% by weight of the zeolites are faujasite zeolites.
The aluminium silicates used in the process according to the invention are commercially obtainable and the methods for their production are described in standard works.
Examples of commercially available X-type zeolites may be described by the following formulae:
Nass[(A102)8s(Si02)ios] ~ x H20, K8s[(AIO2)ss(Si02Oos] ~ x H20, Ca4oNas[(A102)8s(Si02)~os] ~ x H20, Sr2~Ba22[(A102)$s(Si02)~os] ~ x H20, in which x may assume a value of 0 to 276 and which have pore sizes of 8.0 to 8.4 A.
For example, a co-crystallizate of zeolite X and zeolite A (ca. 80% by weight zeolite X), which is marketed by CONDEA Augusta S.p.A. under the name of VEGOBOND AX~ and which may be described by the following formula:
nNa20 ~ (1-n)K20 ~ AI203 ~ (2 - 2.5)Si02 (3.5 - 5.5) H20 is commercially obtainable and may be used with advantage in the process according to the invention.
Zeolites of the Y type are also commercially obtainable and may be described, for example, by the following formulae:

Na56I(AIO2)56(SIOz)136~ ' X I"'12~, K56L(AIO2)56(SIO2)136~ ' x H20, in which x is a number of 0 to 276 and which have pore sizes of 8.0 A.
The particle sizes of the faujasite zeolites used in the process according to the invention is in the range from 0.1 to 100 pm, preferably in the range from 0.5 to 50 Nm and more preferably in the range from 1 to 30 Nm, as measured by standard methods for determining particle size.
Besides the nonionic surfactants used in accordance with the invention, the detergents according to the invention may also contain anionic surfactants such as, for example, C$_ZZ alkyl sulfates, C8_22 alkane-sulfonates, C8_22 olefin sulfonates, C8_22 alkyl benzenesulfonates, C$_22 fatty acid ether sulfates, C8_22 fatty acid ester sulfonates, sulfonated fatty acid glycerol esters, 2,3-C8_22-alkyl sulfates, salts, monoesters andlor diesters of alkylsulfosuccinic acid (sulfosuccinates), sulfuric acid monoesters of linear or branched C~_2~ alcohols ethoxylated with 1 to 6 moles ethylene oxide, fatty acid soaps and mixtures thereof.
The detergents according to the invention may additionally contain any substances typically present in detergents, such as inorganic salts, bleaching agents, bleach activators, redeposition inhibitors, foam inhibitors, salts of polyphosphonic acids, optical brighteners, enzymes and mixtures thereof.
The granules produced in accordance with the invention may either be used as sole detergent component or may be mixed and compounded with other particles containing other detergent ingredients.
In one preferred embodiment, the granules are mixed with other detergent ingredients and the resulting mixture is tabletted to form detergent tablets.

Embodiments of the Invention are described by reference to the following Example which is not to be construed as limiting.
Examples A sugar surfactant compound with the composition shown in Table 1 was produced in the first step of the process carried out in a fluidized bed granulator by spraying a 50% alkyl polyglycoside paste and a 40%
Sokalan~ solution (acrylic acidlmaleic acid copolymer, product of BASF
AG, Ludwigshafen). The product obtained was then ground in a mortar mill to a maximum particle size of 0.1 mm.
In the next granulation step, a powder obtained by spray drying with the composition shown in Table 2, C~2_~$ alkyl sulfate and sodium citrate were introduced into a 130 I Lodige mixer in the quantities shown in Table 3. A mixture of nonionic surfactant and the compound produced in the first step of the process was added in the quantities shown in Table 3 and granulated. On completion of the granulation process, the granules were powdered with 3% Wessalith~ XD (zeolite, a product of Degussa AG, Hanau).
In Comparison Example 1, the powder was granulated with a mixture of nonionic surfactant and glycerol; in Comparison Example 2, only nonionic surfactant was used. The granules obtained were sieved to a particle size of 0.6 to 1.6 mm. The granules with a particle size of 0.6 to 1.6 mm are referred to in Table 4 as "accepts". The granules obtained did not have to be dried.
The solubility of the products was tested by the so-called L Test. To this end, 8 g of substance were added to 1000 ml of water with a hardness of 16°dH at 30°C and stirred with a propeller stirrer for 1.5 minutes at 800 r.p.m. The undissolved solids were sieved on a 0.2 mm mesh sieve. The residue was dried to constant weight and weighed. The test results are set out in Table 4.

Table 1:
Composition of the APG compound in C~z-~a alkyl polyglucoside 50 with x = 1.3 Sokalan CP5~ 45 Water, salts 5 Table 2:
Composition of the tower powder in C,2_~8 alkyl benzenesulfonate22.8 Tallow alcohol ~ 5 EO 1.3 C~z_~$ fatty acid soap 1.3 Sodium sulfate 4 Zeolite A 48 Phosphonate 1 Sokalan~ CP5' 8 NaOH 0.5 Water,salts Balance Acrylic acidlmaleic acid copolymer, product of BASF AG, Ludwigshafen Table 3:
Granulation mixtures in %, 8 kg total quantity Tower powder 73 73 73 Sulfopon~ 1218G' 6 6 6 Na citrate 6 6 6 Dehydol~ LT 7 9.2 9.2 12 APG compound 2.8 I I

Glycerol, 86% I 2.8 I

Wessalith XD 3 3 3 Compound containing 92% C12-18 fatty alcohol sulfate (a product of Henkel KGaA) C~2,~$ fatty alcohol ~ 7 EO (a product of Henkel KGaA) Table 4:
Data of the granules Fraction > 1.6 in 12 6 8 %

Fraction < 0.6 in 39 49 42 %

"Accepts" in % 49 45 50 Bulk density in gll 690 610 660 ~L Test 1.5 mins. 3 10 16 ~

The results set out in Table 4 show that the accepts and the bulk density of the granules produced in accordance with the invention and the granules of the Comparison Examples are in similar ranges. However, the solubility of the granules produced in accordance with the invention is distinctly better than that of the comparison granules.

Claims (18)

1. A process for the production of surfactant granules containing nonionic surfactants, wherein A) sugar surfactants are processed in the presence of water-soluble carrier materials to form a compound and B) the compounds obtained in A) are mixed with a non-aqueous solvent and the resulting mixture and optionally other detergent ingredients are granulated by methods known per se.

2. A process as claimed in claim 1, wherein the sugar surfactants are selected from the group of alkyl and alkenyl oligoglycosides corresponding to the following general formula:
R1O(G)X~~ (I) in which R1 is a primary, linear or methyl-branched alkyl or alkenyl group containing 8 to 22 carbon atoms and G stands for a glycose unit containing or 6 carbon atoms, and x is a number of 1 to 10, or polyhydroxy fatty acid amides corresponding to formula (II):
in which R2CO is an aliphatic acyl group containing 6 to 22 carbon atoms, R3 is hydrogen, an alkyl or hydroxyalkyl group containing 1 to 4 carbon atoms and [Z] is a linear or branched polyhydroxyalkyl group containing 3 to 10 carbon atoms and 3 to 10 hydroxyl groups.

3. A process as claimed in claim 2, wherein R1 is a 2-methyl-branched alkyl or alkenyl group.

4. A process as claimed in claims 2 or 3, wherein R1 contains 12 to 18 carbon atoms.

5. A process as claimed in any one of claims 2 to 4, wherein G is glucose.

6. A process as claimed in any one of claims 2 to 5, wherein x has a value of 1.2 to 1.4.

7. A process as claimed in any one of claims 1 to 6, wherein the water-soluble carrier materials are selected from the group consisting of waterglasses, layer silicates and organic polymers.

8. A process as claimed in any one of claims 1 to 7, wherein the compounds produced in step A) have a maximum particle size of 1 mm.

9. A process as claimed in claim 8, wherein the compounds produced in step A) have a maximum particle size of 0.8 mm.

10. A process as claimed in claim 9, wherein the compounds produced in step A) have a maximum particle size of 0.4 mm.

11. A process as claimed in any one of claims 1 to 10, wherein nonionic surfactant is used as the non-aqueous solvent in step B).

12. A process as claimed in claim 11, wherein the nonionic surfactant is a C8-18 fatty alcohol alkoxylate containing 1 to 12 alkoxy groups per molecule.

13. A process as claimed in any one of claims 1 to 12, wherein the granules obtained are powdered with a component having an oil absorption capacity of ~ 20 g/100 g.

14. A process as claimed in any one of claims 1 to 13, wherein the granules obtained are not dried.

15. A process as claimed in any one of claims 1 to 14, wherein other surfactants, builders, inorganic salts, bleaching agents, bleach activators, redeposition inhibitors, foam inhibitors, salts of polyphosphonic acids, optical brighteners, enzymes or mixtures thereof are present as additional detergent ingredients.

16. A process as claimed in claim 15, wherein the other surfactants are anionic surfactants.

17. A process as claimed in claims 15 or 16, wherein the other detergent ingredients are used at least partly in the form of a spray-dried powder.

18. The use of the surfactant granules produced by the process claimed in any one of claims 1 to 17 for the production of detergent tablets.