CA2328047A1 - Producing compacted particles - Google Patents

Abstract

A process is claimed for producing compacted particles, suitable for incorporation into laundry detergents and cleaning products, in which a mixture of solid and, if desired, liquid starting materials is supplied to the chamber of a pelletizer provided with a rigid annular die, the mixture is pressed through the die by means of a rotor arranged rotatably in the chamber and running with pressing faces along the inner surface of the die, and is scraped off in the form of compacted particles.
The process permits the processing of temperature-sensitive components.

Description

PRODUCING COMPACTED PARTICLES
Field of the Invention The present invention relates to a process for producing compacted particles, suitable for incorporation into laundry detergents and cleaning products, in which a mixture of the solid and liquid starting materials is compressed in a pelletizer.
Background of the Invention In the field of solid and free-flowing laundry detergents and cleaning products, the largest share is currently taken by the compacted or agglomerated particulate compositions having high bulk densities.
These compositions have the advantage that owing to the high degree of compaction of the ingredients they possess high bulk densities and therefore require only relatively small packaging. These laundry detergent particles, for example, are produced by extruding mixtures of solid and liquid ingredients or by agglomeration processes.
DE 39 26 253 discloses a process for producing compacted laundry detergents and cleaning products in granule form, in which a solids mixture optionally comprising incorporated liquid ingredients is processed to a homogeneous, shapingly compressible composition, said processing taking place with the addition of water-soluble, water-emulsifiable and/or water-dispersible plasticizers and/or lubricants, this composition is compressed in strand form by way of perforated molds whose perforation widths correspond to the predetermined granule size, the emerging compacted material strands are cut to the predetermined granule size, and, if desired, the plastic granule particles are subsequently shapingly rounded and, if desired, are dried to give particulate, free-flowing granules.

DE 41 00 306 discloses a process for producing dry concentrates, comprising ingredients of laundry detergents and/or cleaning products, in the form of free-flowing and storage-stable compacts of large particle size, in which fine-particled ingredients without pronounced adhesion properties are mixed with fine-particled ingredients having adhesion properties to form a relatively loose bulk product, said mixing taking place substantially homogeneously on fine-particled material under conditions in which no pronounced consolidating adhesive function yet occurs;
the liquid components, if used, are mixed in, and the bulk product is compressed into compacts from the main composition, with very substantial exclusion of shear forces, said compression taking place accompanied by the inclusion of microdisperse air. Compression takes place by means of a die press, especially in an annular die press, where the bulk material is applied to the surface of a rotating die, which possesses bores, is introduced into the bores with compaction by means of the rotation of a compression tool which rotates on or slightly above the die press, and is pressed through these bores in the form of strands, which are cut into granules.
Laundry detergents and cleaning products generally comprise different particulate components each of which is mixed in predetermined proportions to give the finished product. The individual constituents come from different production processes.
In order for the user of particulate products always to take the same ingredients in corresponding proportions in each dose unit taken, it is necessary for the particulate laundry detergents and cleaning products to comprise individual particles having similar shapes and densities. Otherwise, shaking in the course of transit, etc., would be accompanied over time by separation phenomena, and so the amount taken would not have the desired composition.
The bleach activators which are generally present in laundry detergents and cleaning products are substances which lack thermal stability and whose decomposition is manifested in release of vinegar.
DE 40 24 759 discloses a process for producing bleach activators in granule form, in which finely divided bleach activators are mixed with surfactant components, the mixture is homogenized at temperatures of up to a maximum of 80°C, preferably between 45 and 70°C, to form a composition which is compressible in strand form, and this composition is extruded in strand form using increased pressures. The homogenization and the strand-form compression take place, for example, in a pelletizing press whose pan grinder is held at a predetermined operating temperature.
In the case of the substance extrusion described in the prior art, these substances are exposed to high shear forces and pressures in the course of compaction. The residence time may be kept low as a result of the low filling level and high rotary speeds in the apparatus, although this does not make it possible to prevent entirely the decomposition of sensitive materials, such as bleach activators. Furthermore, an excessively long residence time also leads to premature hardening of the material in the extruder.
On the other hand, granulation in a mixer or granulating plate leads to particles of low abrasion stability, so producing an unwanted fine fraction in the products. When the materials are compressed in a pelletizing press with a rotating die, the material for compression is supplied to the press via a conveying screw, the compaction of the material taking place by means of rollers driven indirectly by way of the rotating die, these rollers compacting the material and pressing it into the apertures of the rotating die. In this process, the material frequently slips from the inner surface of the rotating die. This return flow reduces the compaction of the material and may increase its residence time.
Summary of the Invention It is an object of the present invention to provide a process for producing particles, suitable for incorporation into laundry detergents and cleaning products, in which the energy input is reduced in such a way that even temperature-sensitive particles may be processed.
The present invention accordingly provides a process for producing compacted particles, suitable for incorporation into laundry detergents and cleaning products, in which a mixture of solid and, if desired, liquid starting materials is supplied to the chamber of a pelletizer provided with a rigid annular die, the mixture is pressed through the die by means of a rotor which is arranged rotatably in the chamber and which runs with pressing faces along the inner surface of the die, said mixture being scraped off in the form of compacted particles on the outside edge of the die.
More particularly, the present invention provides a process for producing compacted particles suitable for incorporation into laundry detergent and cleaning product preparations comprising supplying a mixture of solid or solid and liquid starting materials to a chamber of a pelletizer provided with a rigid annular die, pressing the mixture through the die by means of a rotor arranged rotatably in the chamber and pressing the mixture with pressing faces located along the inner _ 5 _ surface of the die to form compacted particles on the outer edge of the die which are then scraped off.
It has surprisingly been found that if in order to produce compacted particles the composition for compression is compressed in a die press by means of a rotor arranged rotatably in the chamber of the pelletizer, said rotor having pressing faces which run along the inner surface of a rigid die, the residence time in the interior of the press is low and there is a reduction in the tendency toward hardening or decomposition of the material intended for processing.
A particular advantage is that, owing to the pressing faces on the rotor, the material for compression does not slip through on the inner wall of the die, so that the disadvantages described above do not arise.
The process of the invention is particularly suitable for processing temperature-sensitive materials, such as bleach activators, enzymes, perfume oils, etc.
In one preferred embodiment of the present invention, the rotor which is arranged rotatably in the interior of the pelletizer and which runs with pressing faces along the inner surface of the die is a flywheel. With particular preference, this flywheel has its own drive, i.e., it is not driven indirectly by way of other driven components in the pelletizer or upstream and/or downstream apparatus.
In order to set the predetermined particle size, the pellets emerging from the die are usually scraped off .
In one preferred embodiment, so-called stripping blades are arranged around the outside edge of the die at a predetermined distance from it, and rotate around the outside edge.

After being stripped off, the compacted particles emerging from the pelletizer may be processed further in a conventional manner. First of all they are cooled if necessary. The cooling medium used may be, for example, cooled air. Additionally or alternatively, the compacted particles obtained may be charged with very finely divided solids in order to improve the free-flow properties.
Detailed Description of the Invention In one particularly preferred embodiment, the compacted particles obtained from the die press are subsequently subjected to a further shaping process. The compacted particles produced may have any desired shapes, cylinder or sphere shapes being particularly preferred.
Rounding may take place, for example, directly following the stripping of the particles from the outer surface of the die, as long as the particles are still plastically deformable - i.e., possess a sufficiently high temperature. Rounding may take place in apparatus known from the prior art - for example, in a Marumerizer.
The compacted particles produced in accordance with the invention preferably have bulk densities of at least 500 g/l. Particular preference is given to bulk densities in the range up to 1000 g/l, with bulk densities of between 600 and 900 g/1 being particularly preferred. The bulk densities may in each case be set by way of the predetermined processing conditions as a function of the material properties of the mixture.
In a known manner, the particle size of the particles produced may be set to a range of from 0.7 to 3 mm, by means, for example, of the size of the perforations in the die press and by the spacing of the stripping blades. Compacted particles longer than 3 mm may be broken, for example, to a predetermined length and, if -desired, rounded. Cylindrical particles preferably possess a length of up to 2 mm, whereas preferred spherical particles, which may have been additionally rounded, may have a particle diameter in the range from 1 mm to 2 mm.
The process of the invention may be carried out in order to produce compacted particles of any desired ingredients, which can be incorporated into laundry detergents and cleaning products. To conduct the process, first of all the solid and - if present -liquid starting materials are mixed.
Starting materials which may be processed are any desired ingredients commonly present as solid constituents in laundry detergents and cleaning products. The present process is particularly suitable for processing temperature-sensitive substances, such as bleach activators, enzymes and fragrance oil concentrates.
Bleach activators are used to enhance the bleaching action of laundry detergents and cleaning products at temperatures below 60°C. Examples of bleach activators are compounds which under perhydrolysis conditions give rise to peroxo carboxylic acids having preferably 1 to 10 carbon atoms, in particular 2 to 4 carbon atoms, and/or substituted or unsubstituted perbenzoic acid.
Suitable substances are those which carry O-acyl and/or N-aryl groups of the stated number of carbon atoms, and/or substituted or unsubstituted benzoyl groups.
Preference is given to polyacylated alkylenediamines, especially tetraacetylethylenediamine (TAED), acylated triazine derivatives, especially 1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine (DADHT), acylated glycolurils, especially 1,3,4,6-tetraacetylglycoluril (TAGU), N-acyl imides, especially N-nonanoylsuccinimide (NOSI), acylated phenolsulfonates, especially -n-nonanoyl- or isononanoyloxybenzenesulfonate (n- or iso-NOBS), carboxylic anhydrides, especially phthalic anhydride, isatoic anhydride and/or succinic anhydride, glycolide, acylated polyhydric alcohols, especially triacetin, ethylene glycol diacetate, 2,5-diacetoxy-2,5-dihydrofuran, and the enol esters known from German Patent Applications DE 196 16 693 and DE 196 16 767, and also acetylated sorbitol and mannitol and/or mixtures thereof (SORMAN) described in European Patent Application EP 0 525 239, acylated sugar derivatives, especially pentaacetylglucose (PAG), pentaacetyl-fructose, tetraacetylxylose and octaacetyllactose, and acetylated, optionally N-alkylated glucamine and gluconolactone, triazole and its derivatives, and/or particulate caprolactams and/or caprolactam derivatives; preferably N-acylated lactams, for example, N-benzoylcaprolactam. Hydrophilically substituted acylacetals and acyllactams are likewise used with preference. It is also possible to use nitrile derivatives such as cyanopyridines, nitrite quats and/or cyanamide derivatives. Preferred bleach activators are sodium 4-(octanoyloxy)benzenesulfonate, undecenoyloxybenzenesulfonate (UDOBS), sodium dodecanoyloxybenzenesulfonate (DOBS), decanoyloxy-benzoic acid (DOBA, OBC 10) and/or dodecanoyloxy-benzenesulfonate (OBS 12), and also N-methylmorpho-linium acetonitrile (MMA). Bleach activators of this kind are present in the compacted particles produced in accordance with the invention in amounts of preferably from 40 to 90% by weight, with particular preference from 70 to 90% by weight, based on the finished particle.
The components which may likewise be processed include the enzymes, encompassing proteases, amylases, pullulanases, cullases, cutinases and/or lipases, examples being proteases such as BLAP~, Optimase~, Opticlean~, Maxacal~, Maxapem~, Durazym°, Purafect~ OxP, Esperase~ and/or Savinase°, amylases such as Termamyl~, Amylase-LT~, Maxamyl~, Duramyl~, Purafect~ OxAm, cellulases such as Celluzyme~, Carezyme°, KAC~ and/or the cellulases known from International Patent Applications WO 96/34108 and WO 96/34092, and/or lipases such as Lipolase~, Lipomax~, Lumafast~ and/or Lipozym° . The enzymes used may be in the form of their aqueous solutions, such as concentrated and purified fermenter broths, or may be adsorbed on carrier substances and/or embedded in coating substances.
Dyes and fragrances may also be processed in the process of the invention. As perfume oils and/or fragrances it is possible to use individual odorant compounds, examples being the synthetic products of the ester, ether, aldehyde, ketone, alcohol, and hydrocarbon types. Odorant compounds of the ester type are, for example, benzyl acetate, phenoxyethyl isobutyrate, p-tert-butylcyclohexyl acetate, linalyl acetate, dimethylbenzylcarbinyl acetate, phenylethyl acetate, linalyl benzoate, benzyl formate, ethyl methylphenylglycinate, allyl cyclo-hexylpropionate, styrallyl propionate, and benzyl salicylate. The ethers include, for example, benzyl ethyl ether; the aldehydes include, for example, the linear alkanals having 8-18 carbon atoms, citral, citronellal, citronellyloxy-acetaldehyde, cyclamen aldehyde, hydroxycitronellal, lilial and bourgeonal; the ketones include, for example, the ionones, a-isomethylionone and methyl cedryl ketone; the alcohols include anethole, citronellol, eugenol, geraniol, linalool, phenylethyl alcohol, and terpineol; the hydrocarbons include primarily the terpenes such as limonenes and pinene.
Preference, however, is given to the use of mixtures of different odorants, which together produce an appealing fragrance note. Such perfume oils may also contain natural odorant mixtures, as obtainable from plant sources, examples being pine oil, citrus oil, jasmine oil, patchouli oil, rose oil or ylang-ylang oil.
Likewise suitable are muscatel, sage oil, camomile oil, clove oil, balm oil, mint oil, cinnamon leaf oil, lime blossom oil, juniperberry oil, vetiver oil, olibanum oil, galbanum oil and labdanum oil, and also orange blossom oil, neroli oil, orange peel oil, and sandalwood oil.
Solid ingredients which may be processed in the process of the invention are all customary solid components.
These may be present likewise already in compounded form, i.e., as prefabricated mixtures. Examples of solid ingredients are water-soluble and/or water-insoluble, organic and/or inorganic builders and cobuilders, bleaches, anionic surfactants, compounded nonionic surfactants, and compounded enzymes.
Suitable water-soluble inorganic builder materials are, in particular, polymeric alkali metal phosphates, which may be present in the form of their alkaline, neutral or acidic sodium or potassium salts. Examples thereof are tetrasodium diphosphate, disodium dihydrogen diphosphate, pentasodium triphosphate, so-called sodium hexametaphosphate, and also the corresponding potassium salts, and mixtures of sodium salts and potassium salts. Water-insoluble, water-dispersible inorganic builder materials used are, in particular, crystalline or amorphous alkali metal alumosilicates, in amounts of up to 50% by weight, preferably not more than 40% by weight, and in liquid compositions in particular from 1% by weight to 5% by weight. Among these, preference is given to the crystalline sodium alumosilicates in laundry detergent quality, especially zeolite A, P and, if appropriate, X. Amounts near to the stated upper limit are used preferably in solid particulate compositions. Suitable alumosilicates possess in particular no particles having a size of more than 30 ~tm and preferably consist to the extent of at least 80% by weight of particles having a size below 10 Vim.
Their calcium binding capacity, which may be determined in accordance with the specifications of German Patent DE 24 12 837, is generally in the range from 100 to 200 mg Ca0 per gram.
Suitable substitutes or partial substitutes for said alumosilicate are crystalline alkali metal silicates, which may be present either alone or in a mixture with amorphous silicates. The alkali metal silicates which may be used as builders in the compositions of the invention preferably have a molar ratio of alkali metal oxide to Si02 of less than 0.95, in particular from 1:1.1 to 1:12, and may be amorphous or crystalline.
Preferred alkali metal silicates are the sodium silicates, especially the amorphous sodium silicates, having a molar ratio Na20:Si02 of from 1:2 to 1:2.8. As crystalline silicates which may be present alone or in a mixture with amorphous silicates it is preferred to use crystalline phyllosilicates of the general formula Na2SiX02X+1 ~ yH2~, in which x, which is called the modulus, is a number from 1.9 to 4 and y is a number from 0 to 20, and preferred values for x are 2, 3 or 4.
Preferred crystalline phyllosilicates are those wherein x in the stated general formula adopts the values 2 or 3. In particular, both (3- and 8-sodium disilicates (Na2Siz05 ~ y H20) are preferred, ~3-sodium disilicate, for example, being obtainable by the process described in International Patent Application WO 91/08171.
8-sodium silicates with a modulus of between 1.9 and 3.2 may be prepared in accordance with Japanese Patent Applications JP 04/238 809 or JP 04/260 610. Also possible for use in compositions of the invention are virtually anhydrous crystalline alkali metal silicates, prepared from amorphous alkali metal silicates, of the abovementioned general formula in which x is a number from 1.9 to 2.1, preparable as described in European Patent Applications EP 0 548 599, EP 0 502 325 and EP 0 452 428. In a further preferred embodiment of compositions of the invention, a crystalline sodium phyllosilicate having a modulus of from 2 to 3 is used, as may be prepared from sand and sodium carbonate. In a further preferred embodiment of compositions of the invention, crystalline sodium silicates having a modulus in the range from 1.9 to 3.5 are used. In a preferred embodiment of compositions of the invention, a granular compound of alkali metal silicate and alkali metal carbonate is used, as is described, for example, in International Patent Application WO 95/22592 or as is available commercially, for example, under the name Nabion~ 15. If alkali metal alumosilicate, especially zeolite, is also present as an additional builder substance, the weight ratio of alumosilicate to silicate, based in each case on anhydrous active substances, is preferably from 1:10 to 10:1. In compositions containing both amorphous and crystalline alkali metal silicates, the weight ratio of amorphous alkali metal silicate to crystalline alkali metal silicate is preferably from 1:2 to 2:1 and in particular from 1:1 to 2:1.
As the zeolite it is possible, for example, to use finely crystalline, synthetic zeolite containing bound water, such as zeolite A, zeolite P and mixtures of A
and P. An example which may be mentioned of a commercially available zeolite P is zeolite MAP~
(commercial product from Crosfield).
As further zeolites which are used with preference and are particularly suitable, mention should be made of zeolites of the faujasite type. Together with the zeolites X and Y, the mineral faujasite belongs to the faujasite types within the zeolite structural group 4, which is characterized by the double-hexagon subunit D6R (compare Donald W. Breck: "Zeolite Molecular Sieves", John Wiley & Sons, New York, London, Sydney, Toronto, 1974, page 92). In addition to the abovementioned faujasite types, the zeolite structural group 4 also includes the minerals chabazite and gmelinite and also the synthetic zeolites R (chabazite type), S (gmelinite type), L, and ZK-5. The two last mentioned synthetic zeolites have no mineral analogs.
Zeolites of the faujasite type are composed of (3 cages linked tetrahedrally by way of D6R subunits, the (3 cages being arranged in a manner similar to the carbon atoms in diamond. The three-dimensional network of the faujasite-type zeolites used in the process of the invention has pores of 2.2 and 7.4 A; the unit cell includes, moreover, 8 cavities having a diameter of approximately 13 A and may be described by the formula Nae6 [ (A102) 86 (Si02) 1061 ~ 264 H20. The network of zeolite X
includes a cavity volume of approximately 50%, based on the dehydrated crystal, which constitutes the largest empty space of all known zeolites (zeolite Y:
approximately 48o cavity volume, faujasite:
approximately 47% cavity 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 term "faujasite-type zeolite" denotes all three zeolites which form the faujasite subgroup of the zeolite structural group 4. In addition to zeolite X, therefore, zeolite Y and faujasite, and mixtures of these compounds, may be used in accordance with the invention, preference being given to straight zeolite X.
Mixtures or cocrystallizates of zeolites of the faujasite type with other zeolites, which need not necessarily belong to the zeolite structural group 4, may also be used in accordance with the invention, the advantages of the process of the invention being manifested particularly if at least 50% by weight of the zeolites are faujasite-type zeolites.
The aluminum silicates which are used in the process of the invention are commercially available, and the methods of their preparation are described in standard monographs.
Examples of commercially available zeolites of the X
type may be described by the following formulae:
Naa6 [ (AlO2) 86 (SlO2) 106 'X H2O, Ka6 [ (AlOz) a6 (SiOz) lost 'x HzO, Ca4oNa6 [ (AlOz) e6 (SiOz) los] 'x H20, SrzlBazz [ (AlOz) as (SiOz) 106 'x H20, in which x may adopt values of between 0 and 276, and which have pore sizes of from 8.0 to 8.4 A.
A product also available commercially and able to be used with preference in the context of the process of the invention, for example, is a cocrystallizate of zeolite X and zeolite A (approximately 80% by weight zeolite X), which is sold by CONDEA Augusta S.p.A.
under the brand name VEGO-BOND AX~ and may be described by the formula nNazO' (1-n) K20'A1203' (2-2 . 5) SiOz' (3 . 5-5.5) HzO.
Zeolites of the Y type are also commercially available and may be described, for example, by the formulae Na56 [ (Al O2) 56 (SlO2) 136 'x H2O, K56 ~ (AlO2) 56 (S1O2) 136 'X H2O, in which x stands for numbers between 0 and 276, and which have pore sizes of 8.0 A.
The particle sizes of the faujasite-type zeolites used in the process of the invention are within the range from 0.1 up to 100 Vim, preferably between 0.5 and 50 Vim, and in particular between 1 and 30 Vim, in each case measured with standard particle size determination methods.
It is of course also possible to use the widely known phosphates as builder substances, provided such a use is not to be avoided on ecological grounds. Among the large number of commercially available phosphates, the greatest importance in the laundry detergents and cleaning products industry is possessed by the alkali metal phosphates, with particular preference pentasodium and pentapotassium triphosphate (sodium and potassium tripolyphosphate, respectively).
Alkali metal phosphates is the collective term for the alkali metal (especially sodium and potassium) salts of the various phosphoric acids, among which meta-phosphoric acids (HP03)n and orthophosphoric acid H3P04, in addition to higher-molecular-mass representatives, may be distinguished. The phosphates combine a number of advantages: they act as alkali carriers, prevent limescale deposits on machine components, and lime incrustations on fabrics, and additionally contribute to cleaning performance.
Sodium dihydrogen phosphate, NaH2P04, exists as the dehydrate (density 1.91 g cm-3, melting point 60°) and as the monohydrate (density 2.04 g cm-3). Both salts are white powders of very ready solubility in water which lose the water of crystallization on heating and undergo transition at 200°C to the weakly acidic diphosphate (disodium dihydrogen diphosphate, Na2H2P207) and at the higher temperature into sodium trimetaphosphate (Na3P309) and Maddrell's salt (see below). NaH2P04 reacts acidically; it is formed if phosphoric acid is adjusted to a pH of 4.5 using sodium hydroxide solution and the slurry is sprayed. Potassium dihydrogen phosphate (primary or monobasic potassium phosphate, potassium biphosphate, PDP), KHzP04, is a white salt with a density of 2.33 g cm-3, has a melting point of 253° [decomposition with formation of potassium polyphosphate (KP03)X], and is readily soluble in water.
Disodium hydrogen phosphate (secondary sodium phosphate), Na2HP04, is a colorless, crystalline salt which is very readily soluble in water. It exists in anhydrous form and with 2 mol (density 2.066 g cm-3, water loss at 95°) , 7 mol (density 1.68 g cm-3, melting point 48° with loss of 5 H20), and 12 mol of water (density 1.52 g cm-3, melting point 35° with loss of 5 H20), becomes anhydrous at 100°, and if heated more severely undergoes transition to the diphosphate Na4P207. Disodium hydrogen phosphate is prepared by neutralizing phosphoric acid with sodium carbonate solution using phenolphthalein as indicator.
Dipotassium hydrogen phosphate (secondary or dibasic potassium phosphate), K2HP04, is an amorphous white salt which is readily soluble in water.
Trisodium phosphate, tertiary sodium phosphate, Na3P04, exists as colorless crystals which as the dodecahydrate have a density of 1.62 g cm-3 and a melting point of 73-76°C (decomposition), as the decahydrate (corres-ponding to 19-20% P205) have a melting point of 100°C, and in anhydrous form (corresponding to 39-40% P205) have a density of 2.536 g cm-3. Trisodium phosphate is readily soluble in water, with an alkaline reaction, and is prepared by evaporative concentration of a solution of precisely 1 mol of disodium phosphate and 1 mol of NaOH. Tripotassium phosphate (tertiary or tribasic potassium phosphate), K3P04, is a white, deliquescent, granular powder of density 2.56 g cm-3, has a melting point of 1340°, and is readily soluble in water with an alkaline reaction. It is produced, for example, when Thomas slag is heated with charcoal and potassium sulfate. Despite the relatively high price, the more readily soluble and therefore highly active potassium phosphates are frequently preferred in the cleaning products industry over the corresponding sodium compounds.
Tetrasodium diphosphate (sodium pyrophosphate), Na4P207, exists in anhydrous form (density 2.534 g cm-3, melting point 988°, 880° also reported) and as the decahydrate (density 1.815-1.836 g cm-3, melting point 94° with loss of water). Both substances are colorless crystals which dissolve in water with an alkaline reaction. Na4P207 is formed when disodium phosphate is heated at > 200° or by reacting phosphoric acid with sodium carbonate in stoichiometric ratio and dewatering the solution by spraying. The decahydrate complexes heavy metal salts and water hardeners and therefore reduces the hardness of the water. Potassium diphosphate (potassium pyrophosphate) , K4P207, exists in the form of the trihydrate and is a colorless, hygroscopic powder of density 2.33 g cm-3 which is soluble in water, the pH of the 1% strength solution at 25° being 10.4.
Condensation of NaH2P04 or of KH2P04 gives rise to higher-molecular-mass sodium and potassium phosphates, among which it is possible to distinguish cyclic representatives, the sodium and potassium metaphosphates, and catenated types, the sodium and potassium polyphosphates. For the latter in particular a large number of names are in use: fused or calcined phosphates, Graham's salt, Kurrol's and Maddrell's salt. All higher sodium and potassium phosphates are referred to collectively as condensed phosphates.
The industrially important pentasodium triphosphate, Na5P301o (sodium tripolyphosphate), is a nonhygroscopic, white, water-soluble salt which is anhydrous or crystallizes with 6 H20 and has the general formula Na0-[P(O)(ONa)-O]n-Na where n = 3. About 17 g of the anhydrous salt dissolve in 100 g of water at room temperature, at 60° about 20 g, at 100° around 32 g;
after heating the solution at 100° for two hours, about 8% orthophosphate and 15% diphosphate are produced by hydrolysis. For the preparation of pentasodium triphosphate, phosphoric acid is reacted with sodium carbonate solution or sodium hydroxide solution in stoichiometric ratio and the solution is dewatered by spraying. In a similar way to Graham's salt and sodium diphosphate, pentasodium triphosphate dissolves numerous insoluble metal compounds (including lime soaps, etc.). Pentapotassium triphosphate, KSP301o (potassium tripolyphosphate), is commercialized, for example, in the form of a 50% strength by weight solution (> 23% P205, 25% K20) . The potassium polyphosphates find broad application in the laundry detergents and cleaning products industry. There also exist sodium potassium tripolyphosphates, which may likewise be used for the purposes of the present invention. These are formed, for example, when sodium trimetaphosphate is hydrolyzed with KOH:
(NaP03) 3 + 2 KOH ~ Na3K2P301o + H20 These phosphates can be used in accordance with the invention in precisely the same way as sodium tripolyphospate, potassium tripolyphosphate, or mixtures of these two; mixtures of sodium tripolyphosphate and sodium potassium tripolyphosphate, or mixtures of potassium tripolyphosphate and sodium potassium tripolyphosphate, or mixtures of sodium tripolyphosphate and potassium tripolyphosphate and sodium potassium tripolyphosphate, may also be used in accordance with the invention.
Organic cobuilders which may be used in the laundry detergent and cleaning product tablets of the invention are, in particular, polycarboxylates/polycarboxylic acids, polymeric polycarboxylates, aspartic acid, polyacetals, dextrins, further organic cobuilders (see below), and phosphonates. These classes of substance are described below.
Organic builder substances which may be used are, for example, the polycarboxylic acids, usable in the form of their sodium salts, the term polycarboxylic acids meaning those carboxylic acids which carry more than one acid function. Examples of these are citric acid, adipic acid, succinic acid, glutaric acid, malic acid, tartaric acid, malefic acid, fumaric acid, sugar acids, amino carboxylic acids, nitrilotriacetic acid (NTA), provided such use is not objectionable on ecological grounds, and also 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. In addition to their builder effect, the acids typically also possess the property of an acidifying component and thus also serve to establish a lower and milder pH of laundry detergents or cleaning products. In this context, mention may be made in particular of citric acid, succinic acid, glutaric acid, adipic acid, gluconic acid, and any desired mixtures thereof.
Also suitable as builders are polymeric polycarboxylates; these are, for example, the alkali metal salts of polyacrylic acid or of polymethacrylic acid, examples being those having a relative molecular mass of from 500 to 70,000 g/mol.
The molecular masses reported for polymeric polycarboxylates, for the purposes of this document, are weight-average molecular masses, Mw, of the respective acid form, determined basically by means of gel permeation chromatography (GPC) using a UV
detector. The measurement was made against an external polyacrylic acid standard, which owing to its structural similarity to the polymers under investigation provides realistic molecular weight values. These figures differ markedly from the molecular weight values obtained using poly-styrenesulfonic acids as the standard. The molecular masses measured against polystyrenesulfonic acids are generally much higher than the molecular masses reported in this document.
Suitable polymers are, in particular, polyacrylates, which preferably have a molecular mass of from 2000 to 20,000 g/mol. Owing to their superior solubility, preference in this group may be given in turn to the short-chain polyacrylates, which have molecular masses of from 2000 to 10,000 g/mol, and with particular preference from 3000 to 5000 g/mol.
Also suitable are copolymeric polycarboxylates, especially those of acrylic acid with methacrylic acid and of acrylic acid or methacrylic acid with malefic acid. Copolymers which have been found particularly suitable are those of acrylic acid with malefic acid which contain from 50 to 90% by weight acrylic acid and from 50 to 10°s by weight malefic acid. Their relative molecular mass, based on free acids, is generally from 2000 to 70,000 g/mol, preferably from 20,000 to 50,000 g/mol, and in particular from 30,000 to 40,000 g/mol.
The (co)polymeric polycarboxylates can be used either as powders or as aqueous solutions. The (co)polymeric polycarboxylate content of the compositions is preferably from 0.5 to 20% by weight, in particular from 3 to 10% by weight.
In order to improve the solubility in water, the polymers may also contain allylsulfonic acids, such as allyloxybenzenesulfonic acid and methallylsulfonic acid, for example, as monomers.
Particular preference is also given to biodegradable polymers comprising more than two different monomer units, examples being those comprising, as monomers, salts of acrylic acid and of malefic acid, and also vinyl alcohol or vinyl alcohol derivatives, or those comprising, as monomers, salts of acrylic acid and of 2-alkylallylsulfonic acid, and also sugar derivatives.
Further preferred copolymers are those whose monomers are preferably acrolein and acrylic acid/acrylic acid salts, and, respectively, acrolein and vinyl acetate.
Similarly, further preferred builder substances that may be mentioned include polymeric amino dicarboxylic acids, their salts or their precursor substances.
Particular preference is given to polyaspartic acids and their salts and derivatives.
Further suitable builder substances are polyacetals, which may be obtained by reacting dialdehydes with polyol carboxylic acids having 5 to 7 carbon atoms and at least 3 hydroxyl groups. Preferred polyacetals are obtained from dialdehydes such as glyoxal, glutaraldehyde, terephthalaldehyde and mixtures thereof and from polyol carboxylic acids such as gluconic acid and/or glucoheptonic acid.
Further suitable organic builder substances are dextrins, examples being oligomers and polymers of carbohydrates, which may be obtained by partial hydrolysis of starches. The hydrolysis can be conducted by customary processes; for example, acid-catalyzed or enzyme-catalyzed processes. The hydrolysis products preferably have average molecular masses in the range from 400 to 500,000 g/mol. Preference is given here to a polysaccharide having a dextrose equivalent (DE) in the range from 0.5 to 40, in particular from 2 to 30, DE being a common measure of the reducing effect of a polysaccharide in comparison to dextrose, which possesses a DE of 100. It is possible to use both maltodextrins having a DE of between 3 and 20 and dried glucose syrups having a DE of between 20 and 37, and also so-called yellow dextrins and white dextrins having higher molecular masses, in the range from 2000 to 30,000 g/mol.
The oxidized derivatives of such dextrins comprise their products of reaction with oxidizing agents which are able to oxidize at least one alcohol function of the saccharide ring to the carboxylic acid function.
Likewise suitable is an oxidized oligosaccharide: a product oxidized at C6 of the saccharide ring may be particularly advantageous.
Oxydisuccinates and other derivatives of disuccinates, preferably ethylenediamine disuccinate, are also further suitable cobuilders. Ethylenediamine N,N'-disuccinate (EDDS) is used preferably in the form of its sodium or magnesium salts. Further preference in this context is given to glycerol disuccinates and glycerol trisuccinates as well. Suitable use amounts in formulations containing zeolite and/or silicate are from 3 to 15% by weight.
Examples of further useful organic cobuilders are acetylated hydroxy carboxylic acids and their salts, which may also be present in lactone form and which contain at least 4 carbon atoms, at least one hydroxyl group, and not more than two acid groups.
A further class of substance having cobuilder properties is represented by the phosphonates. The phosphonates in question are, in particular, hydroxyalkane- and aminoalkanephosphonates. Among the hydroxyalkanephosphonates, 1-hydroxyethane-1,1-diphos-phonate (HEDP) is of particular importance as a cobuilder. It is used preferably as the sodium salt, the disodium salt being neutral and the tetrasodium salt giving an alkaline (pH 9) reaction. Suitable aminoalkanephosphonates are preferably ethylenediamine-tetramethylenephosphonate (EDTMP), diethylenetri-aminepentamethylenephosphonate (DTPMP), and their higher homologs. They are used preferably in the form of the neutrally reacting sodium salts, e.g., as the hexasodium salt of EDTMP or as the hepta- and octa-sodium salt of DTPMP. As a builder in this case, preference is given to using HEDP from the class of the phosphonates. Furthermore, the aminoalkanephosphonates possess a pronounced heavy metal binding capacity.
Accordingly, and especially if the compositions also contain bleach, it may be preferred to use aminoalkanephosphonates, especially DTPMP, or to use mixtures of said phosphonates.
Furthermore, all compounds capable of forming complexes with alkaline earth metal ions may be used as cobuilders.

Anionic surfactants used are, for example, those of the sulfonate and sulfate type. Preferred surfactants of the sulfonate type are C9_13 alkylbenzenesulfonates, olefinsulfonates, i.e., mixtures of alkenesulfonates and hydroxyalkanesulfonates, and also disulfonates, as are obtained, for example, from Clz-le monoolefins having a terminal or internal double bond by sulfonating with gaseous sulfur trioxide followed by alkaline or acidic hydrolysis of the sulfonation products. Also suitable are alkanesulfonates, which are obtained from Clz-ie alkanes, for example, by sulfochlorination or sulfoxidation with subsequent hydrolysis or neutralization, respectively. Likewise suitable, in addition, are the esters of a-sulfo fatty acids (ester sulfonates), e.g., the x-sulfonated methyl esters of hydrogenated coconut, palm kernel or tallow fatty acids.
Preferred alk(en)yl sulfates are the alkali metal salts, and especially the sodium salts, of the sulfuric monoesters of Clz-C18 fatty alcohols, examples being those of coconut fatty alcohol, tallow fatty alcohol, lauryl, myristyl, cetyl or stearyl alcohol, or of Clo-C2o oxo alcohols, and those monoesters of secondary alcohols of these chain lengths. Preference is also given to alk (en) yl sulfates of said chain length which contain a synthetic straight-chain alkyl radical prepared on a petrochemical basis, these sulfates possessing degradation properties similar to those of the corresponding compounds based on fatty-chemical raw materials. From a detergents standpoint, the Clz-Cis alkyl sulfates and Clz-Cls alkyl sulfates, and also C14-Cls alkyl sulfates, are preferred. In addition, 2,3-alkyl sulfates, which may for example be prepared in accordance with US Patents 3,234,258 or 5,075,041 and obtained as commercial products from Shell Oil Company under the name DAN~, are suitable anionic surfactants.

Further suitable anionic surfactants are sulfated fatty acid glycerol esters. Fatty acid glycerol esters are the monoesters, diesters and triesters, and mixtures thereof, as obtained in the preparation by esterification of a monoglycerol with from 1 to 3 mol of fatty acid or in the transesterification of triglycerides with from 0.3 to 2 mol of glycerol.
Preferred sulfated fatty acid glycerol esters are the sulfation products of saturated fatty acids having 6 to 22 carbon atoms, examples being those of caproic acid, caprylic acid, capric acid, myristic acid, lauric acid, palmitic acid, stearic acid, or behenic acid.
Also suitable are the sulfuric monoesters of the straight-chain or branched C7_21 alcohols ethoxylated with from 1 to 6 mol of ethylene oxide, such as 2-methyl-branched C9_11 alcohols containing on average 3.5 mol of ethylene oxide (EO) or C12-la fatty alcohols containing from 1 to 4 E0. Because of their high foaming behavior they are used in cleaning products only in relatively small amounts, for example, in amounts of from 1 to 5% by weight.
Further suitable anionic surfactants include the salts of alkylsulfosuccinic acid, which are also referred to as sulfosuccinates or as sulfosuccinic esters and which constitute monoesters and/or diesters of sulfosuccinic acid with alcohols, preferably fatty alcohols and especially ethoxylated fatty alcohols. Preferred sulfosuccinates comprise Ca_la fatty alcohol radicals or mixtures thereof. Especially preferred sulfosuccinates contain a fatty alcohol radical derived from ethoxylated fatty alcohols which themselves represent nonionic surfactants (for description, see below).
Particular preference is given in turn to sulfosuccinates whose fatty alcohol radicals are derived from ethoxylated fatty alcohols having a narrowed homolog distribution. Similarly, it is also possible to use alk(en)ylsuccinic acid containing preferably 8 to 18 carbon atoms in the alk(en)yl chain, or salts thereof.
Further suitable anionic surfactants are, in addition, soaps. Suitable soaps include saturated and unsaturated fatty acid soaps, such as the salts of lauric acid, myristic acid, palmitic acid, stearic acid, hydrogenated erucic acid and behenic acid, and, in particular, mixtures of soaps derived from natural fatty acids, e.g., coconut, palm kernel, olive oil or tallow fatty acids.
The further anionic surfactants, including the soaps, may be present in the form of their sodium, potassium or ammonium salts and also as soluble salts of organic bases, such as mono-, di- or triethanolamine.
Preferably, the anionic surfactants are in the form of their sodium or potassium salts, in particular in the form of the sodium salts.
Among the compounds used as bleaches which yield H202 in water, particular importance is possessed by sodium perborate tetrahydrate and sodium perborate monohydrate. Further bleaches which may be used are, for example, sodium percarbonate, peroxypyrophosphates, citrate perhydrates, and H2O2-donating peracidic salts or peracids, such as perbenzoates, peroxophthalates, diperazelaic acid, phthaloiminoper acid or diperdodecanedioic acid. When using bleaches, too, it is possible to omit surfactants and/or builders, so that straight bleach tablets maybe produced. Where such bleach tablets are to be used for laundering, a combination of sodium percabonate with sodium sesquicarbonate is preferred, irrespective of which other ingredients the tablets comprise. Where detergent or bleach tablets for machine dishwashing are being produced, use may also be made of bleaches from the group of organic bleaches. Typical organic bleaches are the diacyl peroxides, such as dibenzoyl peroxide, for example. Further typical organic bleaches are the peroxy acids, particular examples being the alkyl peroxy acids and the aryl peroxy acids. Preferred representatives are (a) peroxybenzoic acid and its ring-substituted derivatives, such as alkylperoxy-benzoic acids, but peroxy-a-naphthoic acid and magnesium monoperphthalate, (b) aliphatic or substituted aliphatic peroxy acids, such as peroxylauric acid, peroxystearic acid, s-phthalimido-peroxy caproic acid [phthaloiminoperoxyhexanoic acid (PAP)], o-carboxybenzamidoperoxycaproic acid, N-nonenylamidoperadipic acid and N-nonenylamido-persuccinates, and (c) aliphatic and araliphatic peroxy dicarboxylic acids, such as 1,12-diperoxycarboxylic acid, 1,9-diperoxyazelaic acid, diperoxysebacic acid, diperoxybrassylic acid, the diperoxyphthalic acids, 2-decyldiperoxybutane-1,4-dioic acid and N,N-terephthaloyldi(6-aminopercaproic acid) may also be used.
Substances which release chlorine or bromine may also be used in compacted particles incorporated into compositions for machine dishwashing. Among suitable chlorine- or bromine-releasing materials, examples include heterocyclic N-bromoamides and N-chloroamides, examples being trichloroisocyanuric acid, tribromoisocyanuric acid, dibromoisocyanuric acid and/or dichloroisocyanuric acid (DICA) and/or salts thereof with cations such as potassium and sodium.
Hydantoin compounds, such as 1,3-dichloro-5,5-dimethylhydantoin, are likewise suitable.
Examples of nonionic surfactants in solid form are alkyl glycosides, alkoxylated fatty acid alkyl esters, amine oxides, polyhydroxy fatty acid amides or any desired mixtures thereof.
Alkyl glycosides have the general formula RO(G)X, where R is a primary straight-chain or methyl-branched aliphatic radical, especially an aliphatic radical methyl-branched in position 2, containing 8 to 22, preferably 12 to 18, carbon atoms, and G is the symbol representing a glycose unit having 5 or 6 carbon atoms, preferably glucose. The degree of oligomerization, x, which indicates the distribution of monoglycosides and oligoglycosides, is any desired number between 1 and 10; preferably, x is from 1.2 to 1.4.
A further class of nonionic surfactants used with preference, which are used either as sole nonionic surfactant or in combination with other nonionic surfactants, are alkoxylated, preferably ethoxylated, or ethoxylated and propoxylated, fatty acid alkyl esters, preferably having 1 to 4 carbon atoms in the alkyl chain, especially fatty acid methyl esters.
Examples of amine oxides are N-cocoalkyl-N,N-dimethylamine oxide and N-tallowalkyl-N,N-dihydroxy-ethylamine oxide. The amount of these and of the fatty acid alcohol amides is preferably not more than that of the ethoxylated fatty alcohols, in particular not more than half thereof.
Polyhydroxy fatty acid amides have the formula I, R~
R-CO-N-[ZJ f where RCO is an aliphatic aryl radical having 6 to 22 carbon atoms, R1 is hydrogen or an alkyl or hydroxyalkyl radical having 1 to 4 carbon atoms, and [Z] is a linear or branched polyhydroxyalkyl radical having 3 to 10 carbon atoms and from 3 to 10 hydroxyl groups. The polyhydroxy fatty acid amides are known substances which are customarily obtainable 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.
The group of the polyhydroxy fatty acid amides also includes compounds of the formula II
R ~ .o-RZ
I
R-~o-N-~z] ~ i where R is a linear or branched alkyl or alkenyl radical having 7 to 12 carbon atoms, R1 is a linear, branched or cyclic alkyl radical or an aryl radical having 2 to 8 carbon atoms and R2 is a linear, branched or cyclic alkyl radical or an aryl radical or an oxyalkyl radical having 1 to 8 carbon atoms, preference being given to C1_4 alkyl radicals or phenyl radicals, and [Z] is a linear polyhydroxyalkyl radical whose alkyl chain is substituted by at least two hydroxyl groups, or alkoxylated, preferably ethoxylated or propoxylated, derivatives of said radical.
[Z] is preferably obtained by reductive amination of a sugar, e.g., glucose, fructose, maltose, lactose, galactose, mannose, or xylose. The N-alkoxy- or N-aryloxy-substituted compounds may then be converted to the desired polyhydroxy fatty acid amides, for example, by reaction with fatty acid methyl esters in the presence of an alkoxide as catalyst.
Liquid starting materials are generally the nonionic surfactants which are present in liquid form.

Furthermore, it is also possible to add granulating aids, such as paraffins, polyethylene glycols, polyoxyethylene glycols and aqueous solutions of organic builder substances, such as aqueous solutions of acrylic acid-malefic anhydride copolymers. As further liquid components it is also possible to use fragrance oils or aqueous enzyme solutions. For the purposes of the present invention, liquid means that these substances are liquid at the processing temperature.
In the process of the invention, the liquid components are usually used in an amount of from 2 to 10% by weight, preferably from 2 to 8% by weight, based on the finished particles.
Examples of liquid surfactants are the alkoxylated alcohols. Preferred alkoxylated, advantageously ethoxylated, especially primary alcohols used are those having preferably 8 to 18 carbon atoms and on average from 1 to 12 mol of ethylene oxide (EO) per mole of alcohol, in which the alcohol radical may be linear or, preferably, methyl-branched in position 2 and/or may contain a mixture of linear and methyl-branched radicals, as are customarily present in oxo alcohol radicals. Particular preference is given, however, to alcohol ethoxylates having linear radicals from alcohols of natural origin having 12 to 18 carbon atoms, e.g., from coconut, palm, tallow fatty or oleyl alcohol, and having on average from 2 to 8 EO per mole of alcohol. The preferred ethoxylated alcohols include, for example, Clz-14 alcohols having 3 EO, 4 EO or 7 EO, C9-11 alcohol having 7 EO, C13-is alcohols having 3 EO, 5 EO, 7 EO or 8 EO, Clz-la alcohols having 3 EO, 5 EO or 7 EO, and mixtures of these, such as mixtures of Clz-14 alcohol having 3 EO and C12-la alcohol having 7 EO. The stated degrees of ethoxylation are statistical means, which for a specific product may be an integer or a fraction. Preferred alcohol ethoxylates have a narrowed homolog distribution (narrow range ethoxylates, NREs).
In addition to these nonionic surfactants, fatty alcohols having more than 12 EO may also be used.
Examples thereof are tallow fatty alcohol having 14 EO, 25 EO, 30 EO, or 40 EO. In accordance with the invention it is also possible to use nonionic surfactants containing EO and PO groups together in the molecule. In this context, use may be made of block copolymers having EO-PO block units and/or PO-EO block units, and also EO-PO-EO copolymers and PO-EO-PO
copolymers. It is of course also possible to use nonionic surfactants with mixed alkoxylation, in which EO and PO units are distributed not in blocks but at random. Such products are obtainable by the simultaneous action of ethylene oxide and propylene oxide on fatty alcohols.
Examples The components indicated in Table 1 were mixed and homogenized in a Lodige mixer and subsequently supplied via a solids metering system to a die press having a rigid annular die and a rotor arranged rotatably in the chamber and running with pressing faces along the inner surface of the die. The emerging product was broken to the desired length and rounded in a rounder for about 1 minute.

Table 1 Component Example Example Example [% by [% by [% by weight] weight] weight]

Tower powders 79.5 - -FAS compoundz 9.1 20.0 10.0 Trisodium citrate 4.5 - -TAED - 71.0 81.0 PEG 4000 2.3 7.0 7.0 Clz/ls fatty alcohol x 4.6 1.5 1.5 EO

PEG 400 - 0.5 0.5 Residue test/% 17 18 17 ,Abrasion stability/% 5 ~ 4 ~ 5 I

1 The tower powder is a spray-dried product whose ingredients are reproduced in Table 2.
2 The ingredients of the surfactant compound are reproduced in Table 3.
Table 2 - Tower powder Component Amount [% by weight]

Zeolite A 46.25 Sokalan CP 53 8.75 Phosphonate 0.5 C9-13 alkylbenzenesulfonate 31.25 Soap 2.5 Water 10.75 Table 3 - Surfactant granules Component Amount [% by weight]

C1z~18 alkylbenzenesulfonate28.29 Cl2~la alkyl sulfate 7.75 Texapon Z 65 1.93 Cl2~la fatty alcohol x 7 9.48 EO

Tallow alcohol x 5 EO 1.43 Na stearate 1.47 Pyrogenic silica 19.60 Citric acid 1.51 Sodium sulfate 19.60 Sokalan CP 53 3.44 Water 5.50 In each case, attractively shaped compacts were obtained whose abrasion stability and dissolution behavior is markedly better than in the case of compacted particles obtained by conventional processes.
More than 95% of the TAEDs used were detectable in the compacted TAED particles produced. There was no vinegar odor during the production process.
In accordance with the prior art, particles having an abrasion > 30% and residue values > 40% are obtained.
L test To determine the residue behavior and the solubility behavior, respectively, 8 g of the composition under test were scattered with stirring (800 rpm using laboratory stroke/propeller stirring head, centered at a distance of 1.5 cm from the bottom of the glass beaker) into a 2 1 glass beaker and stirring was conducted at 30°C for 1.5 minutes. The test was conducted using water with a hardness of 16°d [German hardness]. Subsequently, the washing liquor was poured through a sieve (80 Vim). The glass beaker was rinsed out via the sieve using a very small amount of cold water. Determination was carried out in duplicate. The sieves were dried to constant weight in a drying oven at 40°C ~ 2°C and the laundry detergent residue was calculated by weighing. The residue is stated in percent as the average of the two individual determinations. In the case of deviations of the individual results by more than 20% from one another, further tests are usually conducted; in the case of the present experiments, however, this was not necessary.
All of the examples investigated showed results in agreement with the comparative example within the bounds of error.
Abrasion:
The abrasion was determined by placing a tablet on a sieve of mesh size 1.6 mm. This sieve was then insert d in a Retsch analytical sieve machine. The tablet was subjected to mechanical stress by sieving for 2 minutes at an amplitude of 2 mm. Weighing of the tablet before and after the stress makes it possible to determine the abrasion directly, and this is stated in % in the table.

Claims (11)

1. A process for producing compacted particles suitable for incorporation into laundry detergent and cleaning product preparations comprising supplying a mixture of solid or solid and liquid starting materials to a chamber of a pelletizer provided with a rigid annular die, pressing the mixture through the die by means of a rotor arranged rotatably in the chamber and pressing the mixture with pressing faces located along the inner surface of the die to form compacted particles on the outer edge of the die which are then scraped off.

2. The process as claimed in claim 1, wherein the rotor is a flywheel.

3. The process as claimed in claim 1 or 2, wherein compacted particles emerging from the die are scraped off by means of a rotary stripping blade.

4. The process as claimed in any of claims 1 to 3, wherein the pellets emerging from the die are rounded in a rounding device.

5. The process as claimed in any of claims 1 to 4, wherein the solid starting materials are selected from builders, bleaches, bleach activators, surfactants and compounded surfactants, enzymes and compounded enzymes.

6. The process as claimed in any of claims 1 to 5, wherein the liquid starting materials are selected from nonionic surfactants, paraffins, polyethylene glycols, polyoxyethylene glycols, aqueous solutions of organic builder substances, fragrance oils or fragrance oil concentrates, and aqueous enzyme solutions.

7. The process as claimed in any of claims 1 to 6, wherein the bulk density is in the range between 500 and 1000 g/l.

8. The process as claimed in any of claims 1 to 6, wherein the bulk density is in the range between 600 to 900 g/l.

9. The process as claimed in any of claims 1 to 8, wherein the compacted particles produced have cylindrical or spherical shape and a particle length or average particle diameter in the range from 0.7 to 3 mm.

10. The process as claimed in any of claims 1 to 8, wherein the compacted particles produced have cylindrical or spherical shape and a particle length or average particle diameter in the range from 1 to 2 mm.

11. The process as claimed in any of claims 1 to 89 wherein the compacted particles comprise from 50 to 98% by weight of bleach activator and from 2 to 50% by weight of binders selected from nonionic surfactants, anionic surfactants, builders and film-forming polymers.