EP1257628A1

EP1257628A1 - Agglomerates containing layered minerals, with non-ionic tensides

Info

Publication number: EP1257628A1
Application number: EP01919340A
Authority: EP
Inventors: Ulrich Sohling; Norbert Schall; Wolfgang Heininger
Original assignee: Sued Chemie AG
Current assignee: Sued Chemie AG
Priority date: 2000-02-25
Filing date: 2001-02-23
Publication date: 2002-11-20
Anticipated expiration: 2021-02-23
Also published as: DE50105195D1; DE10008815A1; ATE287942T1; ES2232608T3; AU2001246473A1; WO2001062883A1; EP1257628B1

Abstract

The invention relates to agglomerates containing layered silicate, with non-ionic tensides, for use as a detergent additive. The agglomerates contain at least one natural or synthetic layered silicate chosen from the group of clays containing montmorillonite, especially betonite, and attapulgite, hectorite and/or beidellite, the quantity thereof being more than 10 wt. % in relation to the total quantity of support materials; at least one precipitated silicic acid, the quantity thereof being at least 12 wt. %, and at least one non-ionic tenside, the quantity thereof being more than 50 wt. %. No compaction or extrusion takes place during the production of the agglomerates.

Description

Agglomerates containing layered minerals with non-ionic surfactants

description

The invention relates to layer silicate-containing agglomerates with nonionic surfactants, a process for their preparation and their use as a detergent additive.

Nonionic surfactants are increasingly used in powder detergents. The reasons for this initially lie in their good washing properties, even at low temperatures. This goes hand in hand with the trend towards lower washing temperatures in European countries and the long-used low washing temperatures in America and Asia. Furthermore, the washing properties of the nonionic surfactants are not influenced or only slightly influenced by a high water hardness. Nonionic surfactants also have better cleaning properties for greasy dirt and for fabrics made of synthetic fibers than anionic surfactants. However, due to their liquid to waxy consistency, the penetration of nonionic surfactants in large quantities into powder detergents is associated with some difficulties. The use of nonionic surfactants in washing powders, which are produced by a spray process, easily leads to a sticking of the nozzles during spray drying and to a swelling of the powder due to the evaporation of volatile impurities in the nonionic surfactants.

In the prior art, the nonionic surfactants are therefore usually applied to the powders only after spray drying. However, the absorption capacity of the powders obtained from the spray drying process does not allow large amounts of nonionic surfactants to be applied or introduced.

Even with powders that are not produced by spray drying, it may be desirable to further increase the content of nonionic surfactants. In this case too, however, the absorption capacity of the powder for further surfactants is limited.

Many detergent compositions which contain solid carrier systems for nonionic surfactants are already known in the prior art. These systems are often limited in their absorption capacity for nonionic surfactants. Furthermore, many of the carrier systems known in the prior art for nonionic surfactants release the latter prematurely during storage. This effect is called "bleeding" of the agglomerates. After all, many known agglomerates are particularly sticky at high loads with non-ionic surfactants and are therefore not free-flowing. JP 0009087699 AA describes a granular nonionic detergent composition containing a nonionic surfactant, a clay mineral such as montmorillonite, an oil absorbing carrier such as amorphous silica, and a silicone. Further additives, such as sodium silicate as a builder, an organic polyacrylate salt, also as a builder, an optical brightener, an enzyme, a bleaching agent and an extender can be present. The ingredients are kneaded and extruded and then crushed. So there is no simple agglomeration.

JP 0011310791 describes a granular, non-ionic detergent composition which contains a nonionic surfactant, a clay mineral and an oil-absorbing carrier. The ingredients are mixed, kneaded, extruded and then crushed. A simple agglomeration process is not described.

US-A-4, 861, 510 describes porous detergent granules which contain sodium sulfate and synthetic layered silicates. The granules are produced by spray drying, producing a porous granulate which can be loaded with liquid surfactants. The liquid absorption capacity is between 2 and 50% by weight, preferably up to 35% by weight. According to the invention, the surfactant content is above 50% and the agglomerates are not produced by spray drying.

DE-A-38 35 918 (= EP-A-0 362 881 = US 5,354,493) describes a process for the production of surfactant-containing granules, which can contain zeolites and bentonites as carrier materials. According to this method, in the mixing stage (a) the nonionic surfactant is mixed with water, which may or may not contain part, but less than 50% by weight of the total amount of water-soluble or water-insoluble solids can be mixed until a gel phase is formed, whereupon in step (b) the remaining main amount of the solids is mixed in and the mixture is mechanically processed until granules are formed. The weight ratio of nonionic surfactant and water in the gel phase to total solids is 25:75 to 65:35. A net content of nonionic surfactant, based on the finished granules, cannot be found in the document. Surfactant contents (based on anhydrous alcohol ethoxylate) of 10 to 20.5% by weight are calculated from the examples. The surfactant content is therefore well below 50% by weight. Since the surfactant absorption capacity of zeolite A is only 26% by weight, it is not possible to produce granules with surfactant contents of more than 50% on the basis of zeolite as the sole carrier material. This is also not possible with carrier mixtures made from bentonites and zeolites, since bentonite granules can only absorb a maximum of about 40% by weight of surfactants.

EP-A-0 690 123 describes a process for the production of a powder detergent, (1) a builder (soda, zeolite, STPP, trisodium nitrilotriacetate, citrates or sulfates or mixtures thereof) is agglomerated with a nonionic surfactant, (2) a barrier material (amorphous silicates / precipitated silicas) is added and (3) further processing with the builder takes place to the final granulate. The total surfactant content is 5 to 50% by weight, which is below the upper limit according to the invention. Furthermore, the products according to the invention are only produced in a maximum of two steps. In addition, the agglomerates according to the invention must contain layer silicates containing montmorillonite. The object of the invention was therefore to provide agglomerates with a high content of nonionic surfactants, which are not sticky, do not "bleed" and enable the nonionic surfactants to be released more rapidly into the wash liquor. Furthermore, the gel effect which is frequently observed when the nonionic surfactants are released should be reduced as far as possible. The resulting gel phases have a high viscosity that prevents the surfactants from dissolving quickly and can cause the particles to stick together when they dissolve.

This object is achieved by the layer silicate-containing agglomerates according to the invention.

The agglomerates according to the invention contain

a) at least one natural or synthetic layer silicate, selected from the group of clays containing montmorillonite, in particular bentonite, and attapulgite, hectorite and / or beidellite (component a), in an amount of more than 10% by weight

b) at least one precipitated silica, in an amount of at least about 12% by weight (component b),

in each case based on the total amount of carrier materials,

c) at least one nonionic surfactant, in an amount of> 50 wt .-% (component c) based on the total

Agglomerate,

no compacting or extrusion taking place during the production of the agglomerate. It has surprisingly been found that the agglomerates according to the invention with the above composition can absorb very high amounts of nonionic surfactants without becoming sticky or "bleeding".

The agglomerates according to the invention can be admixed particularly advantageously with washing powders, the gel formation effect mentioned above being limited to the agglomerates and not covering the entire detergent composition, and also surprisingly small.

It was unexpectedly found that a content of at least about 12% by weight of precipitated silica, preferably of at least about 15 to at least about 20% by weight of precipitated silica, has a synergistic effect with the layer silicates mentioned above and a very high incorporation of nonionic surfactants is made possible without this leading to stickiness or "bleeding" of the agglomerates.

Furthermore, in the agglomerates according to the invention, the rapid dissolution of the agglomerate particles and the rapid release of the nonionic surfactants into the washing liquor are ensured, incrustations on the laundry can also be avoided.

It was found that the montmorillonite-containing silicates, such as bentonite, as well as attapulgite, hectorite and / or beidellite, as natural or synthetic layered silicates, provide particularly advantageous results.

Thus, according to a preferred embodiment, natural or synthetic bentonites (preferably Na bentonite), At- tapulgite, Beidellite and / or Hectorite used. Bentonite and hectorite in particular also have a positive effect on washing performance and a fabric softening effect.

In addition to natural layered silicates, synthetic layered silicates can also be used according to the invention, for example synthetic hectorite.

It was found that prior activation, in particular alkaline activation of the layered silicates, has a positive effect on the properties of the agglomerates according to the invention. According to a particularly preferred embodiment, activated bentonite, in particular bentonite activated with soda, is used, for example.

As mentioned above, a content of precipitated silicas of at least about 12% by weight, based on the total amount of the support materials (components a, b and, if appropriate, d according to claims 1 and 7, respectively) is shown in combination with the natural or synthetic Layered silicates surprisingly have a synergistic effect. The amount of precipitated silica in the agglomerates according to the invention is therefore adjusted so that on the one hand it is at least about 12% by weight, preferably at least about 14% by weight, and in particular at least about 16% by weight, based on the total amount of support materials.

It is assumed, without the invention being restricted to this theoretical mechanism of action, that in the agglomerates according to the invention the layered silicate used, in the manner of a "house of cards" or framework, forms a porous structure for taking up the nonionic surfactant, the structure being formed by the highly porous precipitated silica stabilized is siert and this interacts with the three-dimensional layered silicate structure. The agglomerates according to the invention therefore have a particularly high and relatively stable porosity. In addition, it is assumed that the precipitated silica causes (partial) delamination of the layered silicate.

Compacting or extrusion probably results in a more parallel alignment of the layered silicate flakes, which has a negative effect on the porosity of the agglomerates and their ability to absorb surfactants.

In order not to impair or even destroy this "stabilized house of cards structure", which is particularly suitable for absorbing large amounts of surfactant, the agglomerates according to the invention are therefore neither compacted nor extruded. The person skilled in the art is familiar with what is to be understood by compacting and extrusion, whereby according to the invention such energy inputs are to be avoided which would cause a considerable change in the porosity and density of the agglomerates. Thus, if the energy input is too high or the action of high shear or compression forces, such as in particular in the case of (roller) compaction or extrusion, the above-described stabilized card house structure composed of bentonite flakes and silica particles is adversely affected. Compacting here also means (compacting) kneading.

However, since, apart from the unexpected effect described above, no positive influence of precipitated silicas on the washing properties is known, and on the other hand, precipitated silicas are also quite expensive, it is preferred according to the invention that the amount of precipitated silica used does not exceed 40% by weight. , preferably not more than 30 % By weight, based on the total agglomerates. Surprisingly, despite the relatively small amount of precipitated silica in the agglomerates, very high absorption rates for nonionic surfactants can be achieved, the agglomerates according to the invention being rapidly soluble. Furthermore, the agglomerates according to the invention surprisingly show a significantly lower tack with the same surfactant content as agglomerates according to the prior art.

The agglomerates according to the invention are advantageously produced in the particle sizes customary for detergent additives, which are familiar to the person skilled in the art in this field.

In contrast, when the particles are compacted or extruded, premixing must first be carried out, for example by kneading in cylindrical rollers or by kneading in an extruder, coarse material then being obtained as a cake or extrudate pressed through a nozzle. This material must be comminuted in a subsequent step, which is problematic and energy and cost-intensive, in particular given the high surfactant contents desired according to the invention and the increased stickiness of the compacted or extruded material.

All conventional precipitated silicas known to those skilled in the art can be used in the agglomerates according to the invention. In general, starting materials for the extraction of silicas by wet are alkali silicate solutions, preferably sodium silicate, from which amorphous silicic acid is precipitated by the addition of acid. After filtering, washing and drying, the precipitated product consists of 86 to 88% Si0 ₂ and 10 to 12% water, which is physically bound both in the molecular structure and on the surface, lu as well as from residues of the salt formed during the reaction and small additions of metal oxides. By varying the most important precipitation parameters, such as precipitation temperature, pH value, electrolyte concentration and precipitation time, silicas with different surface properties can be produced. Silicas can be produced in the range of specific surfaces from about 25 to 700 m ² / g.

The silica suspension obtained during the precipitation is transferred to filter presses, the solids content of the filter cake being between about 15 and 20%. Drying takes place according to different processes, which are often followed by grinding and classifying steps.

Both hydrophilic and hydrophobic silicas can be used, whereby hydrophobic silicas can simultaneously serve as defoamers.

The silicas used in the present invention preferably have an average particle diameter of approximately 1 to 100 μm. In most cases, precipitated silicas with a high specific surface area and a high adsorption capacity, which is characterized by the oil number or the dibutyl phthalate number (DBP number) according to DIN 53601, are preferred.

All non-ionic surfactants known to the person skilled in the art can be used to produce the agglomerates. These include, but are not limited to, the group of alcohol ethoxylates or fatty alcohol polyethylene glycol ethers, alkyl polyglycosides, fatty alcohol polyglycol ether methyl esters, fatty acid methyl ester ethoxylates, sorbitan esters or mixtures thereof. Fatty alcohol polyethylene glycol ethers, alkyl polyglycosides, fatty acid methyl ester ethoxylates and Fatty alcohol polyglycol ether methyl ester. Fatty alcohol polyethylene glycol ethers, fatty alcohol polyglycol ether methyl esters or mixtures of the two are particularly preferred. When using fatty acid methyl ester ethoxylates, the agglomerates according to the invention can be dissolved surprisingly quickly.

Preferred fatty alcohol polyethylene glycol ethers are those which are common in detergent applications, i.e. which have degrees of ethoxylation between 1 and 12 and alkyl chain residues with 10 to 17 carbon units. Fatty alcohol polyethylene glycol ethers with a few ethoxylate units are preferably used in mixtures with higher ethoxylated fatty alcohol polyethylene glycol ethers. The preferred non-ionic surfactants in individual cases depend on the specific requirements for the detergent and can be determined by the person skilled in the art on the basis of routine tests.

In addition to the surfactants, the agglomerates can contain additional additives known in the art. In particular in the case of agglomerates with alcohol ethoxylate or fatty alcohol polyethylene glycol ether, additives known in the prior art can be added to the agglomerates according to the invention, such as e.g. Alcohols such as ethanol or glycerin, polyethylene glycols or hydrotropes such as Na cumene sulfonate. The polyethylene glycols used are in particular those which have low molecular weights, in particular 200 to 6000 g / mol. These are generally mixed with the surfactant before agglomeration and used in amounts of 0.1 to 30%, based on the amount of surfactant.

The preferred processes for producing the agglomerates according to the invention are discussed in more detail below. According to a preferred embodiment, the agglomerates according to the invention contain at least 52% by weight, in particular at least 55% by weight, particularly preferably at least 58% by weight, of nonionic surfactants, based on the total agglomerate.

The ratio of layered silicate to precipitated silica, based on% by weight in the agglomerates according to the invention, is preferably between 2: 1 and 1: 2. According to a particularly preferred embodiment, the layered silicate and the precipitated silica are present in approximately the same amounts, based on% by weight.

According to a particularly preferred embodiment of the invention, the agglomerates contain about 10 to 15% by weight of bentonite, about 5 to 15% by weight of zeolite and about 10 to 30% by weight of precipitated silica, based on the total agglomerate.

Although, as mentioned above, the agglomerates according to the invention can additionally contain additives known in the prior art, in a preferred embodiment the agglomerates consist essentially of nonionic surfactant, layered silicate and precipitated silica, so that intimate contact between these components is ensured. The above components preferably make up at least 85% by weight, in particular at least 90% by weight, and particularly preferably about 95% by weight of the agglomerates.

According to a further embodiment of the present invention, it has surprisingly been found that the additional uptake of at least one zeolite into the agglomerates, preferably in the amount between 0.5 and 60% by weight, and in particular between 5 and 30% by weight, based on the carrier mat rial, leads to particularly positive results. It is known that it is not readily possible to obtain agglomerates by agglomeration of zeolite with nonionic surfactant, since the fine particle size of the zeolites makes it difficult to produce agglomerates with the usual particle size in a satisfactory yield.

It has now surprisingly been found that by the targeted combination of zeolite with a layered silicate according to component (a) of claim 1, a precipitated silica according to component (b) from claim 1, and a nonionic surfactant according to component (c) from claim 1, a much better yield of agglomerates in the desired size can be achieved. It is assumed, without the invention being restricted to this assumption, that the layered silicate used acts as a kind of binder and that the interaction of the components enables a particularly high absorption capacity for nonionic surfactants, without this leading to a stickiness of the agglomerates obtained or to "Bleeding" leads. To a certain extent, zeolite also seems to be able to take on the function of the precipitated silica in the "stabilized house of cards structure" described above.

According to the invention, all commercially available zeolites can be used for the agglomerates, for example Wessalith P ^" , Wessalith 200θ ^" from Degussa, Doucil A24 ^" and Doucil A4 ^" from Crosfield, Eijsden, the Netherlands. The layered silicate-containing agglomerates can be produced according to the invention by a process in which

a) at least one natural or synthetic layered silicate, selected from the group of clays containing montmorillonite, in particular bentonite, and attapulgite, hectorite and / or beidellite, in an amount of more than 10% by weight (component a);

b) at least one precipitated silica in an amount of at least about 12% by weight (component b);

in each case based on the total amount of carrier materials,

c) at least one nonionic surfactant in an amount of greater than 50% by weight (component c), based on the total agglomerate;

d) optionally a zeolite, preferably in an amount of 0.5% by weight to 30% by weight, based on the total amount of support materials;

can be mixed and agglomerated intensively without compacting or extrusion.

According to a preferred embodiment, a mechanical fluidized bed is generated for intensive mixing. For this purpose, the intensive mixers known in the prior art can generally be used in batch-wise or continuous processes. If the agglomeration is carried out in batches, batch mixers from Eichrich, Hartheim, Loedige-Mixer (eg Loedige FKM-Mixer, Paderborn) or Drais (Drais Turbomix, Mannheim) can be used. With continuous process control, mixers from Loedige, Paderborn (e.g. Loedige-CB mixer), from Drais, Mannheim (e.g. Drais CoriMix), from Ballestra, Milan, Italy (e.g. Ballestra Cetemix) or from Schugi-Leylistad, Netherlands (e.g. Schugi.) Flexomix) can be used. If a continuous process is used, two mixers can also be combined with one another, such as a Loedige CB mixer and a Loedige KM mixer, whereby coating with an inorganic powder can also take place in the second mixer.

The agglomerates are preferably produced in an intensive mixer by mixing the above-mentioned carrier materials with the surfactant. In many cases, it is preferred to intensively mix the carrier materials (components a, b, and optionally d) beforehand. The surfactant or the surfactant mixture, which is optionally provided with further additives, can be added in the pure state or mixed with water. Water contents are preferably set between 0 and about 50%. Water contents between 0 and about 20% are particularly preferred. The use of the pure surfactants for agglomeration has the advantage that the resulting agglomerates do not have to be dried. This also applies to surfactant-water mixtures that have water contents that correspond to those of the finished washing powder or washing powder tablets.

According to a particularly preferred embodiment, the agglomerate particles are coated (coating) in a second mixer, the structure of the particles being retained.

According to the invention, zeolite, bentonite, talc or titanium dioxide powder are used to coat the agglomerate particles. If the agglomerates according to the invention already contain zeolite, the coating can also be omitted if the whiteness of the agglomerate particles is sufficient and a further reduction in the tackiness is not necessary. According to the present invention, there is preferably no comminution of the agglomerate particles.

Another aspect of the present invention relates to agglomerates containing layered minerals and containing nonionic surfactants which can be obtained by the above process.

According to the invention, the agglomerates are used as additives to detergents. It is particularly advantageous here that the very high content of nonionic surfactants means that only very small amounts of the detergent composition have to be added. As a result, the gel effect mentioned above is also limited to the added agglomerates and is quite low due to the composition of the agglomerates according to the invention. The added agglomerates fulfill both the function of providing a sufficient content of nonionic surfactants and increasing the softness of the laundry.

Another aspect of the present invention relates to a detergent or detergent additive which contains the agglomerates according to the invention.

According to a preferred embodiment of the invention, the agglomerates can be used in detergents which are in tablet form.

The invention is explained in more detail below with the aid of examples, which are only used for illustration and are not intended to limit the invention in any way. Examples

Introduction to the examples: Implementation of agglomerations

Unless stated otherwise, an Eirich R02E intensive mixer was used to produce the agglomerates discussed in the following examples. The low setting (level 1) for the rotation speed of the plate and the maximum rotation speed for the vertebrate were chosen. Unless otherwise stated, the agglomeration parameters were chosen below so that more than 50% of the agglomerates were in a particle size range of 0.2-1.2 mm. As is known in the art, the average particle size can be modified by routine selection of the production parameters. The agglomerates were, if indicated, with inorganic powders such as e.g. Talc or zeolite coated (coated). The following processes were used for this: In a first variant, the material was transferred to a plastic bag, the inorganic powder was added and shaken for about 2 minutes. In a further variant, the coating (coating) was carried out in the Eirich mixer. For this purpose, after the agglomeration, the inorganic powder was added for coating and the agglomerate / powder mixture was then mixed again for 2 minutes. The other results were comparable.

Measurements of the dissolution behavior of the nonionic surfactants in the agglomerates

To determine the dissolution behavior of the surfactants as a function of time, the measurement of the surface tension of the solution of the agglomerates was used. The surface tension was measured as a function of time after the bladder pressure method with an online tensiometer, SITA-Online F10. A bubble frequency of 1 Hz was used to record the measurement curves. Standardized samples with particle sizes between 0.2 and 1.2 mm were used for the measurements. 1 g samples were used, placed in 200 ml of distilled water and stirred with a 1.5 cm long stirring fish at a frequency of 150 revolutions. In this measurement, the surface tension can serve as a measure of the surfactant release. The most commonly used surfactant Genapol OA 070 in a concentration of 0.5 g / l was used as a comparison. Such a solution had a surface tension of 30-32 mN / m under the same measurement conditions.

Determination of bulk density:

The bulk density (bulk density) was determined in the examples below by pouring 100 g of the agglomerates into a 1,000 ml can and shaking for about 30 seconds.

The measuring cylinder is weighed empty to 10 mg. The powder funnel is then attached to the opening of the cylinder using a stand and clamp. After starting the stopwatch, the measuring cylinder is filled with the agglomerates within 15 seconds. With the spatula, filling material is continuously refilled, so that the measuring cylinder is always slightly protruding. After 2 minutes, the excess is wiped off with a spatula, taking care that no pressing forces compress the material in the cylinder. The filled measuring cylinder is brushed off and weighed.

The bulk density is given in g / 1. In general, the bulk densities obtained allow more than 600 g / 1, in particular more than 650 g / 1, also a use of the agglomerates according to the invention in common compact detergents.

Example 1: Agglomerates of nonionic surfactants and mixtures of the precipitated silica Sipernat 50 and the bentonite EX0255

For this purpose, the corresponding powders were placed in an Eirich mixer and agglomerated by slowly adding the surfactant. As component a) an alkaline activated bentonite from Süd-Chemie (EX0255), as component b) the precipitated silica Sipernat 50, available from Degussa, Frankfurt, and as component c) the nonionic surfactant Imbentin-C / 135/070 used by the Kolb company. As a comparative example, the pure bentonite and the pure precipitated silica were agglomerated with the nonionic surfactant. In all cases, so much surfactant was added that free-flowing agglomerates were still obtained. The surfactant content of the agglomerates produced is listed in the following table. To increase the whiteness, these can be coated with 10% Wessalith P.

Table 1: Agglomerates of non-ionic surfactants and mixtures of Sipernat 50 and bentonite as solid carriers

The above results are shown graphically in Figure 1.

For comparison, the straight line drawn in Figure 1 shows the course that one would expect with an ideal mixing behavior of the carrier materials with regard to the binding capacity for nonionic surfactants. As can be seen from Table 1 and Figure 1, the content of non-ionic surfactants in the agglomerates at levels above about 12% precipitated silica, based on the total amount of carrier materials, increases significantly disproportionately when a part of the bentonite is replaced by the precipitated silica. For the above agglomerates, the rate of surfactant release was determined by measuring the interfacial tension as a function of the stirring time using the method described above.

It was found that in the mixtures according to Table 1, the addition of the precipitated silica to the bentonite improved the surfactant release. This effect was particularly significant for the silica contents according to the invention from about 12% by weight, based on the support materials, which was shown by a considerable reduction in the interfacial tension.

Example 2: Agglomerates of nonionic surfactants and mixtures of Sipernat 22 and EX 0255 as solid carriers

Analogously to Example 1 above, mixtures of Sipernat 22 (from Degussa, Frankfurt) with the bentonite EX 0255 from Süd-Chemie AG (sodium bentonite with high swelling capacity) were investigated. The resulting agglomerates were coated with 10% Wessalith P (zeolite) for the further investigations. The results obtained are shown in Table 2 below.

Table 2: Agglomerates from mixtures of EX 0255 and Sipernat 22 with the non-ionic surfactant Genapol OA 070

The results from Table 2 are shown graphically in Figure 2 below.

As in Example 1, the use of more than about 12% by weight of precipitated silica showed a disproportionate increase in the surfactant absorption capacity. Likewise, the investigation of the surfactant release from the agglomerates shown in Table 2 showed results comparable to those given in Example 1.

The above data also show that replacing half of the bentonite with the precipitated silica produces agglomerates with a surfactant content which is only about one percent lower than that of the pure precipitated silica to let .

The good agglomeration of these systems was also documented in the size distribution of the agglomerates. Thus, with a carrier material made of 50% Sipernat 22 and 50% EX 0255, agglomerates were obtained after coating with zeolite, of which over 80% were in a size range between 0.2 and 1.2 mm. The fine fraction (agglomerates with sizes smaller than 0.2 mm) was less than 5% in this system after optimization of the manufacturing parameters. The bulk density of these agglomerates was 650 g / i.

Example 3: Agglomerates from mixtures of Laundrosil DGA with different precipitated silicas

Analogous agglomerates could also be produced with mixtures of Laundrosil DGA, a sodon-activated bentonite, available from Süd-Chemie AG, and other precipitated silicas. In these cases too, the agglomerates were coated with 10% Wessalith P. The following table 3 lists the composition and bulk density of the agglomerates that were sieved to sizes of 0.2-1.2 mm:

Table 3: Agglomerates from mixtures of Laundrosil DGA and various precipitated silicas as well as the non-ionic surfactant Genapol OA 070

As can be seen from the table, free-flowing granules with very high levels of nonionic surfactants can also be produced by using further precipitated silicas in the agglomerates according to the invention. The surfactant release test as stated above in Example 1 showed a very rapid release of the nonionic surfactants from the agglomerates according to the invention given in Table 3 above.

Example 4: Comparison of the agglomeration according to the invention in the intensive mixer with an extrusion or compacting

In order to document the advantages of the manufacturing method according to the invention by agglomeration of an intensive mixer, this was examined in comparison to a compacting or extrusion according to the prior art.

The agglomeration was carried out with the Eιπch-R02E mixer explained above. 200 g of Sipernat 22 were initially charged with 200 g of Laundrosil DGA in an egg mixer and after intensive mixing the powder was agglomerated with Genapol OA 070. Agglomerates with a content of 59% were received napol OA 070. These can optionally be coated with 10% Wessalith P (zeolite) by adding the appropriate amount of zeolite to the agglomerates and mixing the mixture again. The process can be optimized so that a maximum of 20% of the agglomerates are larger than 2 mm and a maximum of 20% of the agglomerates are smaller than 0.5 mm.

Granulating press / extrusion

After intensive mixing of the above composition as described above in an Eirich R15 mixer and the addition of 10% zeolite A, a granulating press type Kahl 38/604 K from Amandus Kahl, Hamburg, was used for the extrusion.

A throughput of 2 t / h was tested. It was found that the material used was too dry for extrusion and could not be extruded at room temperature or pressed through the nozzles of the granulating press. This could be avoided by adding water, but this has a disadvantageous effect on the product properties, since either subsequent drying is required or the added water has to be transported with the product, which increases the transport costs of the end product. With some difficulty, it was only possible to obtain granules which had a cylindrical shape with a length of 2 mm and a diameter of 2 to 3 mm.

The crushing required before adding to a washing powder could not be carried out after pressing on the extruder, since the knives stuck together and the system had to be cleaned at very short intervals. The few granulate particles obtained also had a slower surfactant release than the agglomerates produced according to the invention. guess.

compacting

The same material was used for the compacting as was used for the extrusion described above. A compactor from Sahut Conreur S.A. (Raismes-France) used, which was equipped with cylinders with a length of 600 mm and a diameter of 145 mm. The compactor was run at 8 revolutions per minute and pressures of 2.5 - 5 t / cm. The distance between the two cylinders was 2 mm. The power consumption of the compactor was 26 kW. The throughput was 2.7 t / h.

It was found that the nonionic surfactant was partially pressed out of the raw material. This resulted in the rollers sticking together. For this reason, the resulting end product was very difficult to shred and sieve and showed considerable stickiness.

In summary, it was found that the agglomerates produced according to the invention had advantageous properties in relation to extruded or compacted materials in terms of surfactant absorption, low stickiness and rapid surfactant release. In addition, particle sizes of about 0.4 to 2 mm particle diameter, as are common in the detergent industry, could be obtained with high yields. In addition, the process used to produce the agglomerates according to the invention is less time and cost intensive.

It was also shown that due to the high pressure required for compacting and extrusion, some of the surfactant was pressed out of the structure again, as a result of which the advantageous properties of the agglomerates are lost again. To prevent this, additional powder components would have to be added, but this would in turn reduce the content of nonionic surfactants and introduce components that have no positive influence on the washing properties.

The process according to the invention is thus considerably more efficient, less expensive and requires far less machine than is the case with extrusion or compacting, especially since the latter production processes generally require subsequent comminution of the extruded or compacted products.

Example 5: Investigation of the storage stability at 40 ° C over 3 days

In order to investigate the subsequent "bleeding" of the agglomerates, the storage stability was examined as follows:

A sample from Example 2 with a carrier material based on Sipernat 22 and EX0255 in a ratio of 1: 1, which had been coated with 10% Wessalith P to increase the whiteness, was subjected to a 3-day storage test at 40 ° C. in a Heraeus brand drying cabinet subjected. After the storage test, a sieve analysis was carried out in 0.2 mm steps. For comparison, some of the corresponding agglomerates were subjected to a sieve analysis without storing them at 40 ° C. As shown below, the agglomerates are stable under such storage conditions. A clumping could not be demonstrated, since the sieve analyzes of the samples stored at room temperature and of the samples stored at 40 ° C are identical within the measurement error and minor deviations due to the sampling. Example 6: Agglomerates with a fatty acid methyl ester ethoxylate

In this example it was investigated whether the production of agglomerates with a similarly high surfactant content is also possible using fatty acid methyl ester ethoxylate. For this purpose, 400 g of a mixture of Laundrosil DGA and Sipernat 22 in a ratio of 1: 1 were placed in an Eirich mixer with the non-ionic surfactant Genagen 24 MEE 080 (Clariant, Frankfurt) agglomerated by slowly adding the surfactant. Agglomerates with a surfactant content of 58% could be obtained. After coating with 10% Wessalith P and sieving to particle sizes of 0.2-1.2 mm, these had a bulk density of 700 g / l. These agglomerates also show a rapid release of the nonionic surfactant in the test shown above (measurement of the surface tension as a function of the stirring time with 1 g of granules). Surface tension values of 30 - 35 mN / m are achieved after just 70 seconds of stirring.

Example 7: Agglomerates with other bentonites or other layer minerals / influence of the degree of activation of the bentonite

In order to investigate the influence of a previous activation of the bentonite used, the corresponding non-activated bentonite EX0276 was used instead of the bentonite EX0255 used in Examples 1 and 2 above. The agglomerates were prepared as described in Example 1, the respective bentonite being used in a ratio of 1: 1, based on% by weight, with the precipitated silica Sipernat 22. It was shown that when using the non-activated bentonite EX0276 a surfactant content of 54% was achieved, whereas when using the corresponding activated bentonite EX0255 a significantly higher surfactant content of 61% was achieved. This proves the positive influence of an activation of the layered silicate used.

Example 8: Agglomerates using hectorite instead of bentonite

Agglomerates were produced as described in Example 1, the hectorite Optigel SH, available from Süd-Chemie AG, being used instead of the bentonite EX0255. Here, too, it was found that a disproportionate increase in the surfactant absorption capacity was observed from a content of about 12% by weight of precipitated silica. With a ratio of hectorite: precipitated silica = 1: 1, a surfactant content of 58% could be achieved. 3υ

Example 9: Agglomerates of nonionic surfactants and mixtures of zeolite, bentonite and precipitated silica

Using Laundrosil DGA (Süd-Chemie AG) as a layered metal component, Wessalith P (Degussa) as a zeolite component and Sipernat 22 (Degussa) as a precipitated silica, agglomerates were prepared according to Example 1, which the above components m m m the table below 4 specified ratios included.

Table 4: Agglomerates with ternary carrier mixtures made from layered silicate, precipitated silica and zeolite

Surprisingly, it was found that, compared to Example 7 (or Example 3), by replacing part of the precipitated silica with zeolite, the maximum nonionic surfactant content is reduced only slightly (by 2%), although the pure zeolite (Wessalith P) only has a surfactant absorption capacity of about 30%. Obviously, the zeolite can functionally replace the precipitated silica in the stabilized "house of cards" structure of the agglomerates according to the invention.

Claims

Claims:

1. Agglomerates containing phyllosilicate with nonionic surfactants as detergent additive, containing

a) at least one natural or synthetic layered silicate, selected from the group of clays containing montmorillonite, in particular bentonite, and attapulgite, hectorite and / or beidellite in an amount of more than 10% by weight (component a), b) at least one precipitated silica , in an amount of at least about 12% by weight (component b), in each case based on the total amount of carrier materials, c) at least one nonionic surfactant, in an amount of> 50% by weight (component c) based on the total Agglomerate, with no compacting or extrusion taking place during the production of the agglomerate.

2. Agglomerates according to claim 1, characterized in that they contain at least 52% by weight, in particular at least 55% by weight, of nonionic surfactant.

3. agglomerates according to claim 1 or 2, characterized in that they contain up to 75 wt .-%, and in particular up to 80 wt .-%, of nonionic surfactant.

4. Agglomerates according to one of the preceding claims, characterized in that they have a content of at least 15% by weight, in particular at least 20% by weight of precipitated silica, based on the total amount of carrier materials.

5. agglomerates according to any one of the preceding claims, characterized in that the ratio of layered silicate to precipitated silica, based on weight percent, between 1:20 and 20: 1, preferably between 2: 1 and 1: 2, in particular at about 1: 1 lies.

6. Agglomerates according to one of the preceding claims, characterized in that components a) to c) make up at least 85% by weight, preferably at least 90% by weight, and particularly preferably at least 95% by weight of the agglomerates.

7. agglomerates according to any one of claims 1 to 5, characterized in that in addition at least one zeolite (component d) preferably in an amount between 0.5 and 60 wt .-%, in particular between 5 and 30 wt .-% based on the Backing materials are included.

8. agglomerates according to any one of the preceding claims, characterized in that about 10 to 50 wt .-% bentonite, about 5 to 40 wt .-% zeolite and about 10 to 50 wt .-% precipitated silica are contained.

9. agglomerates according to claim 6 or 7, characterized in that components a) to d) make up at least 85% by weight, preferably at least 90% by weight, and particularly preferably at least 95% by weight of the agglomerates.

10. Process for the preparation of layered silicate-containing agglomerates with nonionic surfactant, wherein a) at least one natural or synthetic layered silicate, selected from the group of clays containing montmorillonite, in particular bentonite, and attapulgite, hectorite and / or beidellite, in an amount of more than 10 % By weight (compo- nente a); b) at least one precipitated silica, in an amount of at least about 12% by weight (component b); in each case based on the total amount of carrier materials, c) at least one nonionic surfactant, in an amount of> 50% by weight (component c), based on the total agglomerate; d) optionally at least one zeolite, preferably in an amount of 0.5% by weight to 60% by weight, based on the total amount of support materials, are mixed and agglomerated intensively without compaction or extrusion.

11. The method according to claim 10, characterized in that more than 60%, in particular more than 80% of the particles have a particle diameter between 0.1 and 3 mm, in particular between 0.2 and 2 mm, particularly preferably between 0.4 and 1 , 4 mm.

12. The method according to claim 10 or 11, characterized in that the intensive mixing and agglomeration takes place in a mechanically generated fluidized bed.

13. The method according to any one of claims 10 to 12, characterized in that the device for intensive mixing is a continuously or discontinuously operated intensive mixer.

14. The method according to any one of claims 10 to 13, characterized in that the aggomerate particles are coated in a second mixer, the particles being retained.

15. The method according to any one of claims 10 to 14, characterized in that zeolite, bentonite, talc or titanium dioxide powder are used for coating.

16. Layer mineral-containing agglomerates with nonionic surfactants, obtainable by the process according to one of claims 10 to 15.

17. Use of the layer mineral-containing agglomerates with nonionic surfactants according to one of claims 1 to 9 in a detergent.

18. Use according to claim 17, wherein the layer mineral-containing agglomerates are used in an amount of 0.5 to 60 wt .-%, in particular 1 to 40 wt .-%, and particularly preferably 5 to 25 wt .-%, in the detergent ,

19. Use according to one of claims 17 and 18, characterized in that the detergent is in tablet form.

20. Detergent or detergent additive containing the agglomerates according to one of claims 1 to 9.