WO2000071657A1

WO2000071657A1 - Method for producing surfactant granulates

Info

Publication number: WO2000071657A1
Application number: PCT/EP2000/004328
Authority: WO
Inventors: Andreas Lietzmann; Kathleen Paatz; Wilfried Rähse; Markus Semrau; Keiwan Ebrahimzadeh
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 1999-05-22
Filing date: 2000-05-13
Publication date: 2000-11-30
Also published as: CA2308932A1; DE19923627A1

Abstract

The invention relates to a method for producing surfactant granulates, containing non-ionic surfactants and additional detergent components. In said method, the solid and optionally liquid components are granulated in the presence of a mixture of a non-ionic surfactant and a non-aqueous solvent. The method is characterised in that the non-aqueous solvent is liquid polyalkylene glycol at 80 DEG C. Said method produces granulates with a narrow particle spectrum and good solubility.

Description

Process for the preparation of surfactant granules

The present invention relates to a process for the preparation of surfactant granules containing nonionic surfactants, in which the solid and optionally liquid constituents are granulated in the presence of a mixture of nonionic surfactant and a nonaqueous solvent.

Compacted or highly concentrated detergent powders or tablets represent a significant proportion of the commercially available detergents and cleaning agents. These agents are generally not obtained by a spray drying process, but rather by mixing, granulating and compacting processes in which high temperatures are avoided. Because of the relatively low temperatures, the removal of water which is introduced by the starting substances is relatively lengthy. A subsequent drying step is often necessary after the granulation has been completed.

Another problem is the deterioration in the solubility of the relatively highly compacted particles. In particular, recipes with a high proportion of alkoxylated fatty alcohols often have this problem. An improvement in solubility can be achieved if alkyl polyglycosides are incorporated into the granules. The incorporation of the alkyl polyglycosides is problematic, however, since they cannot be processed by spray drying processes and the resulting particles have a high level of stickiness.

The removal of water from the granules is often incomplete and leads to products with fluctuating water content. In particular, if the granules are to be further processed into tablets which must have a quick and constant water solubility, the use of granulated precursors with fluctuating water content can lead to tablets with inconsistent dissolution rates. The production of surfactant granules is known from the prior art. International patent application WO 97/09415, for example, discloses a production process for a non-spray-dried particulate surfactant composition which has a bulk density of at least 600 g / l and contains a polymeric builder component and / or a soil release polymer. The granulating liquid and solid components 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 for the production of particulate surfactant compositions with a bulk density below 700 g / l. To produce the disclosed surfactant composition, a particulate starting material which has at least 10% by weight of a component with a bulk density of not more than 600 g / l and which is not a surfactant compound is first mixed with a liquid binder in a granulator and then granulated. The particulate starting material contains a builder, surfactant or a precursor thereof is contained in the particulate starting material and / or in the binder.

International patent application WO 97/22685 discloses a process for producing particulate detergent and cleaning agent compositions with bulk densities between 300 and 1300 g / l. In the process disclosed, particulate starting material is mixed with the addition of a liquid binder and partially granulated. The partially granulated mixture is transferred to a low shear granulator, further liquid binder is added and the granulation is continued until a particulate powder with the desired bulk density has formed. Water, anionic surfactant, nonionic surfactant or mixtures thereof can be used as the liquid binder.

European patent application 0 799 884 describes a process for producing free-flowing particulate surfactant compositions

Alkylpolyglycosides described that a final drying step should not be necessary. To carry out the described method, first a Mixture made from an aqueous alkyl polyglycoside paste, an ethoxylated nonionic surfactant and a solid water-soluble inorganic salt. The mixture obtained separates into an organic phase and a water-rich phase, the organic phase containing alkyl polyglycoside, ethoxylated nonionic surfactant and water being separated off. The proportion of the individual components in the first step is selected so that in the organic phase the ratio of alkyl polyglycoside to ethoxylated nonionic surfactant within the range from 35:65 to 65:35 and the ratio of ethoxylated nonionic surfactant to the total amount of water within the range from 90: 10 to 60: 10 lies. To prepare the surfactant compositions, the mixture obtained and optionally further surfactants are mixed with one or more particulate carrier materials and processed to a particulate product in a conventional high-speed mixer or granulator.

The above-described processes have the disadvantage that they are either very complex to carry out or lead to products which are not free-flowing and sometimes have poor solubility.

Another disadvantage is that the products obtained have a broad particle size distribution. In particular when further processing the granules produced into products with a larger particle size, detergent tablets, uniform products are only obtained if the starting components used have only a slight variance in their properties.

The object of the present invention was to provide a process for the production of surfactant granules which does not have the disadvantages mentioned above. In particular, a method should be found that leads to granules with a good and constant solubility and a narrow particle spectrum. Furthermore, granules should be obtained which show such a flowability that no further drying step is required.

It has surprisingly been found that the disadvantages of the prior art can be improved by combining the solid and liquid detergent components in the presence of a mixture of nonionic liquid Granulated surfactant and a polyethylene glycol liquid at 80 ° C as a non-aqueous solvent. Free-flowing granules with good solubility and a narrow grain spectrum are obtained.

The present application accordingly relates to a process for the preparation of surfactant granules containing nonionic surfactants and other detergent components, in which the solid and optionally liquid components are granulated in the presence of a mixture of nonionic surfactant and a non-aqueous solvent, which is characterized in that the non-aqueous solvent is polyalkylene glycol liquid at 80 ° C.

The polyalkylene glycol used according to the invention can also be a mixture of several alkylene glycols. A preferably used polyalkylene glycol is polyethylene glycol, in particular a polyethylene glycol with a molecular weight from 100 to 10,000, in particular from 300 to 4,000.

All liquid nonionic surfactants suitable in the field of detergents and cleaning agents are suitable as nonionic surfactants. Alkoxylated, advantageously ethoxylated, in particular primary alcohols having preferably 8 to 18 carbon atoms and an average of 1 to 12 moles of ethylene oxide (EO) per mole of alcohol are used, in which the alcohol radical can be linear or preferably methyl-branched in the 2-position or linear and may contain methyl-branched radicals in the mixture, as are usually present in oxo alcohol radicals. However, alcohol ethoxylates with linear residues of alcohols of native origin with 12 to 18 carbon atoms, for example from coconut, palm, tallow or oleyl alcohol, and an average of 2 to 8 EO per mole of alcohol are particularly preferred. The preferred ethoxylated alcohols include, for example, C ₁₂ -C ₁₄ alcohols with 3 EO or 4 EO, C ₉ -C _ι alcohols with 7 EO, C ₁₃ -C ₁₅ alcohols with 3 EO, 5 EO, 7 EO or 8 EO , C ₁₂ -C ₁₈ alcohols with 3 EO, 5 EO or 7 EO and mixtures thereof, such as mixtures of C ₁₂ -C ₁₄ alcohol with 3 EO and C ₁₂ -C ₁₈ alcohol with 7 EO. The degrees of ethoxylation given represent statistical averages, which can be an integer or a fraction for a specific product. Preferred alcohol ethoxylates have a narrow homolog distribution (narrow range ethoxylates, NRE). In addition to the preferred fatty alcohol alkoxylates, other nonionic surfactants such as alkyl polyglycosides, alkoxylated, preferably ethoxylated or ethoxylated and propoxylated C ₈ -C ₁₈ fatty acid alkyl esters, N-fatty alkyl amine oxides, polyhydroxy fatty acid amides or mixtures thereof can also be used.

The content of the nonionic surfactants in the finished granules is preferably from 5% by weight to 25% by weight.

Particularly good results are obtained when the nonionic surfactant and the polyalkylene glycol are used in a mixing ratio of 10: 1 to 1:10 in the process according to the invention.

Inorganic and organic builder substances and further surfactants, in particular anionic surfactants, can be incorporated into the surfactant granules as further constituents. Furthermore, the agents according to the invention can have all the substances normally contained in washing and cleaning agents, such as inorganic salts, bleaching agents, bleach activators, graying inhibitors, foam inhibitors, salts of polyphosphonic acids, optical brighteners, enzymes or mixtures thereof.

In a preferred embodiment, the further constituents are incorporated in the second process step as spray-dried powder. Temperature-sensitive or water-sensitive components can be added separately.

All builders suitable for washing and cleaning agents can be used as builders, which have a sufficiently large inner surface to be able to absorb the nonionic surfactant. Examples of inorganic builders are zeolites, crystalline layered silicates, amorphous silicates, soda, phosphates and mixtures thereof, zeolite being preferred.

As the zeolite, for example, finely crystalline, synthetic and bound water-containing zeolite such as zeolite A, zeolite P and mixtures of A and P can be used. Zeolite MAP® (commercial product from Crosfield) may be mentioned as commercially available zeolite P. Zeolites of the faujasite type are to be mentioned as further preferred and particularly suitable zeolites. Together with the zeolites X and Y, the mineral faujasite belongs to the faujasite types within the zeolite structure group 4, which is characterized by the double six-ring subunit D6R (compare Donald W. Breck: "Zeolite Molecular Sieves", John Wiley & Sons , New York, London, Sydney, Toronto, 1974, page 92). In addition to the faujasite types mentioned, the zeolite structure group 4 also includes the minerals chabazite and gmelinite and the synthetic zeolites R (chabazite type), S (gmelinite type), L and ZK-5. The latter two synthetic zeolites have no mineral analogues.

Faujasite-type zeolites are made up of ß-cages which are tetrahedral linked by D6R subunits, the ß-cages being arranged similar to the carbon atoms in the diamond. The three-dimensional network of the faujasite-type zeolites used in the process according to the invention has pores of 2.2 and 7.4 Å, the unit cell also contains 8 cavities with a diameter of approximately 13 Å and can be determined using the formula Na ₈₆ [(AIO ₂ ) ₈₆ (SiO ₂ ) ₁₀₆ ] ^• 264 H ₂ O. The network of zeolite X contains a void volume of approximately 50%, based on the dehydrated crystal, which represents the largest empty space of all known zeolites (zeolite Y: approx. 48% void volume, faujasite: approx. 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 term “zeolite of the faujasite type” denotes all three zeolites which form the faujasite subgroup of the zeolite structure group 4. In addition to zeolite X, zeolite Y and faujasite and mixtures of these compounds can also be used according to the invention, pure zeolite X being preferred.

Mixtures or cocrystallizates of zeolites of the faujasite type with other zeolites which do not necessarily have to belong to the zeolite structural group 4 can also be used according to the invention, the advantages of the process according to the invention being particularly evident when at least 50% by weight of the zeolites Faujasite type zeolites.

The aluminum silicates used in the process according to the invention are commercially available, and the methods for their presentation are described in standard monographs.

Examples of commercially available X-type zeolites can be described by the following formulas:

Na ₈₆ [(AIO ₂ ) ₈₆ (SiO ₂ ) ₁₀₆ ] ^• x H ₂ O,

K ₈₆ [(AIO ₂ ) ₈₆ (SiO ₂ ) ₁₀₆ ] ^■ x H ₂ O,

Ca ₄₀ Na ₆ [(AIO ₂ ) ₈₆ (SiO ₂ ) ₁₀₆ ] x H ₂ 0,

Sr ₂₁ Ba ₂₂ [(AIO ₂ ) ₈₆ (SiO ₂ ) ₁₀₆ ] ^■ x H ₂ O,

in which x can have values between 0 and 276 and the pore sizes range from 8.0 to 8.4 Å.

Preferably commercially available and within the scope of the inventive method is used, for example, a co-crystallizate of zeolite X and zeolite A (ca. 80 wt .-% zeolite X) which is marketed by CONDEA Augusta SpA under the trade name VEGOBOND AX ^® and through the formula

nNa ₂ O ^• (1-n) K ₂ O ^■ AI ₂ O ₃ ^■ (2 - 2.5) SiO ₂ ^■ (3.5 - 5.5) H ₂ O

can be described.

Y-type zeolites are also commercially available and can be expressed, for example, by the formulas

Na ₅₆ [(AIO ₂ ) ₅₆ (SiO ₂ ) ₁₃₆ ] ^• x H ₂ O,

K ₅₆ [(AIO ₂ ) ₅₆ (SiO ₂ ) ₁₃₆ ] ^• x H ₂ O,

in which x stands for numbers between 0 and 276 and the pore sizes of 8.0 Å have, describe.

The particle sizes of the faujasite-type zeolites used in the process according to the invention are in the range from 0.1 to 100 μm, preferably between 0.5 and 50 μm and in particular between 1 and 30 μm, in each case measured using standard particle size determination methods.

Suitable builders are, for example, crystalline, layered sodium silicates of the general formula NaMSi _x O _2x + 1.yH ₂ O, where M is sodium or hydrogen, x is a number from 1, 9 to 4 and y is a number from 0 to 20 and is preferred Values for x are 2, 3 or 4. Such crystalline layered silicates are described, for example, in European patent application EP-A-0 164 514. Preferred crystalline layered silicates of the formula given are those in which M represents sodium and x assumes the values 2 or 3. In particular, both β- and δ-sodium disilicate Na ₂ Si ₂ O ₅ .yH ₂ O are preferred, whereby β-sodium disilicate can be obtained, for example, by the method described in international patent application WO-A-91/08171.

Furthermore, amorphous sodium silicates with a module Na ₂ O: SiO ₂ of 1: 2 to 1: 3.3, preferably from 1: 2 to 1: 2.8 and in particular from 1: 2 to 1: 2.6, can also be used as builder substances be used, which are preferably delayed release and have secondary washing properties. The dissolution delay compared to conventional amorphous sodium silicates can be done in various ways, for example by surface treatment, compounding,

Compacting / compaction or caused by overdrying. In the context of this invention, the term “amorphous” is also understood to mean “X-ray amorphous”. This means that the silicates in X-ray diffraction experiments do not provide sharp X-ray reflections, as are typical for crystalline substances, but at most one or more maxima of the scattered X-rays, which have a width of several degree units of the diffraction angle. However, it can very well lead to particularly good builder properties if the silicate particles deliver washed-out or even sharp diffraction maxima in electron diffraction experiments. This is to be interpreted as meaning that the products have microcrystalline areas of size 10 to a few hundred nm, values up to max. 50 nm and in particular up to max. 20 nm are preferred. Such so-called X-ray amorphous silicates, which also have a release delay compared to conventional water glasses are described, for example, in German patent application DE-A-44 00 024. Compacted / compacted amorphous silicates, compounded amorphous silicates and over-dried X-ray amorphous silicates are particularly preferred.

Usable organic carrier materials are, for example, the polycarboxylic acids which can be used in the form of their sodium salts, polycarboxylic acids being understood to mean those carboxylic acids which carry more than one acid function. For example, these are citric acid, adipic acid, succinic acid, glutaric acid, malic acid, tartaric acid, maleic acid, fumaric acid, sugar acids, aminocarboxylic acids, nitrilotriacetic acid (NTA), as long as such use is not objectionable for ecological reasons, and mixtures of these. Preferred salts are the salts of polycarboxylic acids such as citric acid, adipic acid, succinic acid, glutaric acid, tartaric acid, sugar acids and mixtures of these.

The acids themselves can also be used. In addition to their builder effect, the acids typically also have the property of an acidifying component and thus also serve to set a lower and milder pH value for detergents or cleaning agents. Citric acid, succinic acid, glutaric acid, adipic acid, gluconic acid and any mixtures thereof can be mentioned in particular.

Polymeric polycarboxylates are also suitable as builders, for example the alkali metal salts of polyacrylic acid or polymethacrylic acid, for example those with a relative molecular weight of 500 to 70,000 g / mol.

For the purposes of this document, the molecular weights given for polymeric polycarboxylates are weight-average molecular weights M _{w of} the particular acid form, which were determined in principle by means of 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 due to its structural relationship with the polymers investigated. This information differs significantly from the molecular weight information for which polystyrene sulfonic acids are used as standard. The molecular weights measured against polystyrene sulfonic acids are generally significantly higher than the molecular weights given in this document. Suitable polymers are, in particular, polyacrylates, which preferably have a molecular weight of 2,000 to 20,000 g / mol. Because of their superior solubility, the short-chain polyacrylates which have molar masses from 2000 to 10000 g / mol, and particularly preferably from 3000 to 5000 g / mol, can in turn be preferred from this group.

Also suitable are copolymeric polycarboxylates, in particular those of acrylic acid with methacrylic acid and of acrylic acid or methacrylic acid with maleic acid. Copolymers of acrylic acid with maleic acid which contain 50 to 90% by weight of acrylic acid and 50 to 10% by weight of malic acid have proven to be particularly suitable. Their relative molecular weight, based on free acids, is generally 2,000 to 70,000 g / mol, preferably 20,000 to 50,000 g / mol and in particular 30,000 to 40,000 g / mol.

The (co) polymeric polycarboxylates can be used either as a powder or as an aqueous solution. The content of (co) polymeric polycarboxylates in the agents is preferably 0.5 to 20% by weight, in particular 3 to 10% by weight.

To improve water solubility, the polymers can also contain allyl sulfonic acids, such as, for example, in EP-B-727448 allyloxybenzoisulfonic acid and methallylsulfonic acid, as a monomer.

Also particularly preferred are biodegradable polymers composed of more than two different monomer units, for example those which, according to DE-A-43 00 772, are salts of acrylic acid and maleic acid as well as vinyl alcohol or vinyl alcohol derivatives or according to DE-C -42 21 381 contain as monomers salts of acrylic acid and 2-alkylallylsulfonic acid as well as sugar derivatives.

Further preferred copolymers are those which are described in German patent applications DE-A-43 03 320 and DE-A-44 17 734 and preferably contain acrolein and acrylic acid / acrylic acid salts or acrolein and vinyl acetate as monomers.

Other suitable organic builder substances are dextrins, for example oligomers or polymers of carbohydrates that can be obtained by partial hydrolysis of starches. The hydrolysis can be carried out by customary processes, for example acid-catalyzed or enzyme-catalyzed. They are preferably hydrolysis products with average molar masses in the range from 400 to 500,000 g / mol. A polysaccharide with a dextrose equivalent (DE) in the range from 0.5 to 40, in particular from 2 to 30, is preferred, DE being a customary measure of the reducing action of a polysaccharide compared to dextrose, which has a DE of 100 , is. Both maltodextrins with a DE between 3 and 20 and dry glucose syrups with a DE between 20 and 37 as well as so-called yellow dextrins and white dextrins with higher molar masses in the range from 2000 to 30000 g / mol can 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. Such oxidized dextrins and processes for their preparation 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 as well as international patent applications WO 92 / 18542, WO 93/08251, WO 93/16110, WO 94/28030, WO 95/07303, WO 95/12619 and WO 95/20608. An oxidized oligosaccharide according to German patent application DE-A-196 00 018 is also suitable. A product oxidized at C _{6 of} the saccharide ring can be particularly advantageous.

Oxydisuccinates and other derivatives of disuccinates, preferably ethylenediamine disuccinate, are further suitable cobuilders. Ethylenediamine N, ^{N'-disuccinate} (EDDS), whose synthesis is described for example in US 3,158,615, preferably in the form of its sodium or magnesium salts. Also preferred in this connection are glycerol disuccinates and glycerol trisuccinates, as described, for example, in US Pat. Nos. 4,524,009, 4,639,325, European Patent Application EP-A-0 150 930 and Japanese Patent Application JP 93/339896 become. Suitable amounts for use in formulations containing zeolite and / or silicate are 3 to 15% by weight. Other useful organic cobuilders are, for example, acetylated hydroxycarboxylic acids or their salts, which may also be in lactone form and which contain at least 4 carbon atoms and at least one hydroxyl group and a maximum of two acid groups. Such cobuilders are described, for example, in international patent application WO 95/20029.

Other suitable carrier materials are oxidation products of carboxyl group-containing polyglucosans and / or their water-soluble salts, as are described, for example, in international patent application WO-A-93/08251 or whose preparation is described, for example, in international patent application WO-A-93/16110 . Oxidized oligosaccharides according to German patent application DE 196 00 018 are also suitable.

Also to be mentioned as further preferred builder substances are polymeric aminodicarboxylic acids, their salts or their precursor substances. Particularly preferred are polyaspartic acids or their salts and derivatives, of which it is disclosed in German patent application DE-A-195 40 086 that in addition to cobuilder properties they also have a bleach-stabilizing effect.

Further suitable builder substances are polyacetals, which can be obtained by reacting dialdehydes with polyolcarboxylic acids which have 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, terephthalaldehyde and their mixtures and from polyol carboxylic acids such as gluconic acid and / or glucoheptonic acid.

Another class of substances with cobuilder properties are the phosphonates. These are, in particular, hydroxyalkane or aminoalkane phosphonates. Among the hydroxyalkane phosphonates, 1-hydroxyethane-1,1-diphosphonate (HEDP) is of particular importance as a cobuilder. It is preferably used as the sodium salt, the disodium salt reacting neutrally and the tetrasodium salt in an alkaline manner (pH 9). Preferred aminoalkane phosphonates are ethylenediamine tetramethylene phosphonate (EDTMP), diethylene triamine pentamethylene phosphonate (DTPMP) as well as their higher homologues in question. They are preferably in the form of the neutral sodium salts, e.g. B. as the hexasodium salt of EDTMP or as the hepta and octa sodium salt of DTPMP. HEDP is preferably used as the builder from the class of the phosphonates. The aminoalkanephosphonates also have a pronounced ability to bind heavy metals. Accordingly, it may be preferred, particularly if the agents also contain bleach, to use aminoalkanephosphonates, in particular DTPMP, or to use mixtures of the phosphonates mentioned.

In addition, all compounds that are able to form complexes with alkaline earth metal ions can be used as cobuilders.

In addition to the nonionic surfactants employed in this invention, the inventive compositions may also contain anionic surfactants such as C ₈ -C ₂₂ alkyl sulfates, C ₈ -C ₂₂ alkanesulfonates, C ₈ - C ₂₂ olefin sulfonates, C ₈ -C ₂₂ alkylbenzene sulfonates, C ₈ - C ₂₂ fatty acid ether sulfates, C ₈ -C ₂₂ fatty acid ester sulfonates, sulfated fatty acid glycerol esters, 2,3-C ₈ -C ₂₂ alkyl sulfates, salts, monoesters and / or diesters of alkyl sulfosuccinic acid (sulfosuccinates), sulfuric acid monoesters with 1 to 6 moles Ethylene oxide ethoxylated straight-chain or branched C ₇ -C ₂₁ alcohols, fatty acid soaps or mixtures thereof.

Furthermore, the agents according to the invention can have all the substances normally contained in washing and cleaning agents, such as inorganic salts, bleaching agents, bleach activators, graying inhibitors, foam inhibitors, salts of polyphosphonic acids, optical brighteners, enzymes or mixtures thereof.

In a preferred embodiment, the nonionic surfactant is first mixed with the polyalkylene glycol. The mixture obtained is applied to the builder in a manner known per se, usually the builder is impregnated with the mixture obtained. In a further process step, the impregnated builder is mixed with other components and granulated.

The granulation can optionally be carried out with the addition of auxiliaries such as organic builders, e.g. B. polycarboxylic acids, citric acid, adipic acid, succinic acid, glutaric acid, tartaric acid, sugar acids, aminocarboxylic acids, nitrilotriacetic acid (NTA), polymers Carboxylates, the sodium salts of the aforementioned carboxylic acids and mixtures thereof, are carried out, provided that the auxiliaries do not impair the solubility of the agents according to the invention.

The granulation can be carried out in a large number of apparatuses customarily used in the detergent and cleaning agent industry. For example, it is possible to use the rounding agents commonly used in pharmacy. In such turntable devices, the residence time of the granules is usually less than 20 seconds. Conventional mixers and mixing granulators are also suitable for granulation. Both high-intensity mixers ("high-shear mixers") and normal mixers with lower circulation speeds can be used as mixers. Suitable mixers are, for example, Eirich® mixers of the R or RV series (trademark of Maschinenfabrik Gustav Eirich, Hardheim), Schugi® Flexomix, the Fukae® FS-G mixers (trademark of Fukae Powtech, Kogyo Co., Japan) Lödige® FM, KM and CB mixers (trademark of Lödige Maschinenbau GmbH, Paderborn) or the Drais® series T or KT (trademark of Drais-Werke GmbH, Mannheim). In all types of mixers and rounders, the particles are granulated by liquid bonding of the non-aqueous binders. The residence times of the granules in the mixers are in the range of less than 60 seconds, the residence time also being dependent on the circulation speed of the mixer. The dwell times are reduced accordingly the faster the mixer runs. The residence times of the granules in the mixer / rounder are preferably less than one minute, preferably less than 15 seconds. In slow-running mixers, e.g. a Lödige KM, retention times of up to 20 minutes are set, retention times below 10 minutes being preferred because of the process economy.

In the process of press agglomeration, the surfactant-containing granules are compressed under pressure and under the action of shear forces, homogenized in the process and then discharged from the apparatus in a shaping manner. The most technically significant press agglomeration processes are extrusion, roller compaction, pelleting and tableting. In the context of the present invention, preferred press agglomeration processes used to produce the surfactant-containing granules are extrusion, roller compaction and pelletization. After completion of the granulation, a dry product is obtained which does not have to be subjected to any further drying step.

The granules obtained can be powdered with an oil absorption component in order to further improve their processability and meterability. This powdering step with a finely divided component binds the liquids to the surface of the granules, so that the granules cannot freeze during storage. The oil absorption component should have an oil absorption capacity of at least 20g / 100g, more preferably at least 50g / 100g, preferably at least 80g / 100g, particularly preferably at least 120g / 100g and in particular at least 140g / 100g.

The oil absorption capacity is a physical property of a substance that can be determined using standardized methods. For example, the British standard methods BS1795 and BS3483: Part B7.1982 exist, both of which refer to the ISO 787/5 standard. In the test methods, a balanced sample of the substance in question is placed on a plate and refined flaxseed oil (density: 0.93 gcm-3) from a burette is added dropwise. After each addition, the powder is mixed intensively with the oil using a spatula, the addition of oil being continued until a paste of smooth consistency is obtained. This paste should flow or run without crumbling. The oil absorption capacity is now the amount of the added oil, based on 100g absorbent and is given in ml / 100g or g / 100g, conversions about the density of the linseed oil are easily possible.

The oil absorption component preferably has the smallest possible average particle size, since the active surface increases with decreasing particle size. Preferred detergent tablets contain a component with an oil absorption capacity of at least 20 g / 100 g, which has an average particle size of less than 50 μm, preferably less than 20 μm and in particular less than 10 μm.

A large number of substances are suitable as an oil absorption component. There are a large number of both inorganic and organic substances which have a large oil absorption capacity. Examples include finely divided substances that to be obtained by precipitation. For example, silicates, aluminosilicates, calcium silicates, magnesium silicates and calcium carbonate are used as substances. Diatomaceous earth (diatomaceous earth) and finely divided cellulose fibers or derivatives thereof can also be used in the context of the present invention. Preferred detergent tablets are characterized in that the component contained in them with an oil absorption capacity of at least 20 g / 100 g is selected from silicates and / or aluminosilicates, in particular from the group of silicas and / or zeolites. Here, for example, finely divided zeolites can be used, but also pyrogenic silicas (Aerosil ^® ) or silicas that have been obtained by precipitation.

The granules produced according to the invention can either be used as the sole detergent component or can be mixed and packaged with other particles which contain further detergent components.

In a preferred embodiment, the granules are mixed with further detergent components and pressed into detergent tablets.

Examples

To prepare the surfactant granules, a spray-dried powder with the composition shown in Table 1, C ₁₂ -C ₁₈ alkyl sulfate and sodium citrate in the amounts shown in Table 2 were placed in a 130 l Lödige mixer. Then a mixture of C _12/18 fatty alcohol was 7 x EO (Dehydol LT7 ^®) and polyethylene glycol having a molecular weight of 400 was added and granulated. After completion of the granulation% Wessalith ^® XD (zeolite, a commercial product Degussa AG, Hanau of Fa.) Was treated with powdered 3.

In comparative example 1, a mixture of nonionic surfactant and glycerol was used for granulation, in comparative example 2 only nonionic surfactant. The granules obtained were then sieved between 0.6 and 1.6 mm. The proportion of the granules which has a particle size between 0.6 and 1.6 mm is referred to as good grain in Table 3.

The solubility of the products was examined in the so-called L test. 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 at 800 rpm for 1.5 minutes. The undissolved solids were sieved with a sieve with a mesh size of 0.2 mm. The residue was dried to constant weight and weighed. The test results are shown in Table 4.

Table 1: Composition of the tower powder in%

1 acrylic acid-maleic acid copolymer, commercial product from BASF AG, Ludwigshafen Table 2: Granulation batches in% by weight based on 100% of the components used

Table 3: Data of the granules

The results shown in Table 3 show that the proportion of good grain in the granules produced according to the invention is significantly higher than the granules from the comparative experiments and that the solubility of the granules produced according to the invention is also significantly better than that of the granules produced according to the comparative experiments.

Claims

claims

1. A process for the preparation of surfactant granules containing nonionic surfactants and other detergent components, in which the solid and optionally liquid components are granulated in the presence of a mixture of nonionic surfactant and a non-aqueous solvent, characterized in that the non-aqueous solvent is liquid polyalkylene glycol at 80 ° C .

2. The method according to claim 1, characterized in that the polyalkylene glycol is a polyethylene glycol, in particular a Poylethylenglycol with a molecular weight of 100 to 10,000, in particular from 300 to 4,000.

3. Composition according to claim 1 or 2, characterized in that alkoxylated primary alcohols having 8 to 18 carbon atoms and an average of 1 to 12 moles of alkylene oxide per mole of alcohol are contained as nonionic surfactants.

4. The method according to any one of claims 1 to 3, characterized in that the nonionic surfactant and the polyalkylene glycol are used in a mixing ratio of 10: 1 to 1:10.

5. The method according to any one of claims 1 to 4, the inorganic and organic builder substances and further surfactants, in particular anionic surfactants, inorganic salts, bleaching agents, bleach activators, graying inhibitors, foam inhibitors, salts of polyphosphonic acids, optical brighteners, enzymes or mixtures thereof as further detergent components are.

6. The method according to claim 5, characterized in that the further detergent components are used at least partially in the form of a spray-dried powder.

7. Composition according to one of claims 1 to 6, characterized in that as a builder Zeolites, crystalline layered silicates, amorphous silicates, soda, phosphates and mixtures thereof are used.

8. Composition according to claim 7, characterized in that the zeolite contains at least 50 wt .-% of a zeolite of the faujasite type.

9. The method according to any one of claims 1 to 8, characterized in that the granules obtained are powdered with a component which has an oil absorption capacity> 20g / 100g.

10. The method according to any one of claims 1 to 9, characterized in that the granules obtained are not subjected to a drying step.

11. Use of the surfactant granules, produced according to one of claims 1 to 10, for the production of detergent tablets.