EP0822974B1 - Long shelf life granulate containing bleach activators and its production - Google Patents

Abstract

The granulate is made by granulating a damp powdered mixture of a powdered bleach activator, a powdered granulating agent and an aqueous solution thereof and/or of another granulating agent or an aqueous solution of other active substances of washing or cleaning agents or water by means of agglomerating the damp particles in a mixing granulator and subsequently drying the damp granulate. Before the damp granulate is dried to the desired residual humidity it is taken to another unit (a rounding machine) and caused to rub against one another and on the wall and/or the bottom of the rounding machine and at the same time become compacted to the extent where the granulates, after drying, have a powder density of at least 580 g/l and especially at least 630 g/1. Besides the high powder density, the granulates exhibit an improved degree of whitening and long shelf life on mixing with bleach and alkali-containing products.

Description

The invention relates to a method for producing a storage-stable bleach activator containing granules as a component of an agent for textile washing or for detergents by granulating a damp powder Mixture of a powdery bleach activator, a powdery one Granulation aids and an aqueous solution of the same and / or one other granulating aid or an aqueous solution of other active substances of detergents or cleaning agents or water by means of agglomerating the wet particles in a mixing granulator and then drying the moist granules and, if necessary, sieving oversize and Fine fractions.

In the known production process, for example, a mixing granulator can be a so-called ploughshare mixer (from Lödige) with one in a horizontal cylindrical rotating central shaft are used, attached to the plow shaped paddle. The one after granulating The moist granules obtained can be dried in conventional dryers, e.g. B. in Fluid bed dryers can be processed further. However, problems arise by agglomerating the already finished but still moist ones Granules in the entrance area of the dryer.

Textile detergents and cleaning agents, e.g. B. Means for mechanical Dishwashing, often contain inorganic bleaching compounds Peroxides and peroxohydrates. The main representative is sodium perborate. It hydrolyzes in water to form hydrogen peroxide and allows on this way an oxidative bleach. However, the bleaching effect depends heavily on that Temperature. For example, sodium perborate only has a clear bleaching effect about 60 ° C.

At lower temperatures, the oxidation effect of the inorganic Per compounds can be improved by adding activators. It acts These are usually acylating agents that are in the wash liquor with hydrogen peroxide form organic peracids in an alkaline environment. These show due to their higher oxidation potential compared to hydrogen peroxide A good bleaching effect in the low temperature range. As a well-known example for such a bleach activator, tetraacetylethylenediamine (TAED) may be mentioned.

The bleach activators, for example from the class of the N- and O-acyl compounds, are, however, highly sensitive to hydrolysis, especially in the presence of alkalis common in washing and cleaning agents. The resulting for The shelf life problems of textile detergents also arise reinforced by the fact that the activators are often poorly soluble in water, so that very finely powdered materials with quick dispersibility are used come. The very finely divided shape allows due to the large surface the increased hydrolysis of the activators during their storage. The In other words, sensitivity to hydrolysis leads to an accelerated rate Breakdown of the active oxygen content of the bleach. The loose structure of the known bleach activator granules, the bulk density of about 530 to 550 g / l lies, also "migrating" water in the interior of the granules penetration.

To solve this problem, the bleach activator is in practice considered to be separate Granules produced the dry detergent or cleaning agent mixtures admitted. The storage stability is also increased by the fact that Production of the dry, finely divided bleach activator with a dry, also mixes very finely divided pelletizing agent and only then moistens and granulated. So in the process according to DE 30 11 998 C2 the bleach activator TAED granulated with the granulation aid sodium carboxymethyl cellulose. The Granulation aids distributed homogeneously in the granulate protect the very fine particles Bleach activator particles before the entry of migrating water and diminished in this way the hydrolysis sensitivity of the finished granulate. By doing The method according to European patent application EP-A-0374867 is the Storage stability increased by enveloping the activator with an aid. The powdered activator is used to produce the activator granules first moistened, then mixed with starch or cellulose derivatives and granulated. However, a further increase in is desired Storage stability.

It is also desirable to improve the abrasion stability of the granules the mechanical stability of the bleach activator granules, in order to avoid the or in the case of other mechanical stress resulting fine part as a result To keep the friction between the granules as low as possible.

What is also desired is an improvement in the visual impression of the manufacture detergent and cleaning agent granules, which in the desire for reinforcement of whiteness is expressed. The well-known activator granules namely have a slightly darker appearance than the washing and Detergent granules to which they are added so that they are not uniform results in a white appearance. The dark look of the familiar According to the knowledge of the inventors, granules are made by the adherent very fine to coarser particles caused rough surface, whose microscopic bumps leads to a corresponding shadow formation.

Another requirement arises from a special area of application of the Bleach activator granules. To reduce the proportion of packaging for solid and Free-flowing detergents and cleaning agents are particularly high bulk densities he wishes. Such products can be manufactured in different ways become.

For example, German patent application DE-A-4232494 describes a method for Production of granular bleach activator compositions in the First, a core particle from a bleach or other water-soluble Substance is produced and this core particle with the powdery bleach activator with the help of an organic binder is granulated. Bulk weights of these granules are not disclosed.

Particularly high bulk densities of around 800 g / l and more are combined in one the method known from DE 39 26 253 A1. Here are compacted granules from premixes of solid ingredients of washing and cleaning agents with the addition of water-soluble, water-emulsifiable or water-dispersible plasticizers and / or lubricants. Processed for this one mixes the premixes into a homogeneous mass and compresses them at pressure between 25 and 200 bar via hole shapes with opening widths of the predetermined Granule dimension to strands. The emerging compacted strands will crushed to the predetermined granule dimension. You round them out of the Extruder granulation of warm and moist cylindrical granules in a rounder (rounding machine) with the addition of zeolite NaA powder as Powder off. After drying, sieving and mixing with the rest The final detergent product is obtained from ingredients.

In addition to bleaching agents, the extrudates can also contain bleach activators, e.g. B. TAED, contain. However, since the extrudates contain the usual alkalis for detergents and the bleach activators of the inorganic peroxide compounds in the presence of alkalis are highly sensitive to hydrolysis, it is appropriate to Bleach activators do not coexist with the other solid ingredients extrude, but to produce separately as granules and these the dried Add extrudates.

The relatively loose produced in the known method (DE 30 11 998 C2) Activator granules, however, undesirably reduce the bulk density of the final detergent product. The difference in the density of the extrudates and the Activator granules can also segregate the detergent end product to lead.

Bleach activator granules with one of the above are therefore to be aimed at Extrudate approximate bulk density and a corresponding grain shape. For this purpose, DE 41 43 016 A1 proposes that the activator granules be applied to the same way as those containing the main ingredients of the detergent To produce extrudates. A practically anhydrous mixture of bleach activator, Anionic surfactant, solubilization aids and optionally other additives is homogenized and extruded in the form of a strand using increased pressure. The emerging strands are cut into short pieces and, if necessary rounded and, if desired, classified according to size. The one for extrusion However, the necessary additives disadvantageously limit the maximum possible activator content in the extrudate.

The object of the present invention is to provide a production process for bleach activator granules to develop compared to those produced in the mixing granulator known granules an increased bulk density and a significantly higher mechanical abrasion stability and when mixed with granules including the remaining ingredients of washing and cleaning agents Hydrolyze alkaline components much more slowly, i.e. considerably less degradation of the active oxygen content of the detergent end product cause. In addition, significantly higher levels of activator in the granules than in known extrudate. Finally, the granules should be in the entry area of the dryer no longer agglomerate as in the known method.

This object is achieved according to the invention in the method mentioned at the outset solved that before drying the moist granules to the desired Residual moisture feeds this to another apparatus (fillet) and places it there rub against each other and on the wall and / or floor of the fillet and compacted so much at the same time that the granules after drying Bulk density of at least 580 g / l, in particular of at least 630 g / l exhibit.

According to the invention, therefore, the technically relatively complex, is not extrusion method used at elevated pressures, but between the known process step of wet granulation in a mixing granulator, e.g. B. a ploughshare mixer, and the drying step is a added further process step. Here you leave the granules together and Rub on the inner wall of a rounder sufficiently long so that the The rough surface of the particles created during wet agglomeration smoothes. At the same time, the impacts acting on a granulate grain from all sides lead to a reduction in the geometric size, that is to say a compression, and to a firm connection of the agglomerated grains contained in the granulate finely divided individual particles. The frequent collision also leads to agglomeration several moist granules and a subsequent rounding and thus to compact, rounded granules, that is, to a grain enlargement with simultaneous increase in density. An increased bulk weight as well as a higher mechanical stability is the result. This compaction effect was discussed above the term "compact" summarized.

The very frequent contact and collision of the moist granules with one another in the rounding step according to the invention requires a relatively high density of Pellet cloud in the fillet, which corresponds to a density of a resting bed, thus a much smaller average distance between the granules than each other for example in a fluidized bed.

In addition to increasing the bulk density and mechanical stability shows the manufacturing method according to the invention further advantages. The after Rounded damp granules tend to be significantly less than in known processes (DE 30 11 998 C2) and under normal process conditions no longer at all to agglomerate in the following Drying stage, which is usually carried out in a fluidized bed dryer becomes. The proportion of oversize is therefore considerably lower.

Compared to the granulate produced in the known way, that is Granules according to the invention with a bulk density of about 580 to 700 g / l about 50 to 150 g / l heavier. The bulk density of those produced according to the invention Granules are just as high as those for extrusion DE 41 43 016 A1 manufactured products.

Another advantage is the significantly higher whiteness. The smooth rounded Surface leaves the granulate optically due to less shadow formation appear lighter, so that after mixing into the granules the The main ingredients of the detergents and cleaning agents are visually uniform Appearance results.

The activator granules according to the invention showed further surprising effects. Are the granules containing the main ingredients of the detergent Extrudaten mixed, so one against the theoretical value Disproportionate increase in bulk density observed.

The sensitivity to hydrolysis of the granules according to the invention Mixing to the final detergent or cleaning product and thus degradation the active oxygen content of the finished detergent was at Use of the granules according to the invention surprisingly clearly less than when using the activator granules produced by known methods.

In an advantageous embodiment of the method according to the invention the moist granules in a rounder with rotating, horizontal Base plate with simultaneous injection of a working gas, in particular Cold air, from below between the housing wall and the edge of the base plate rub and compact. Such rounders are known and for example available under the name "Marumerizer" (Fa. Elanco).

The use of such a fillet in a process for granulating Detergents are described in U.S. Patent Application US-A-4059538 described. An advantage according to the invention here is that these Granulation in the fillet runs faster than the spray drying of the Detergent formulation. Notes on the processing of bleach activators in however, the registration does not contain this rudder.

The use of several rounders can also be advantageous. It is proposed that the moist granules in several, in series Rub down (compact cascade) and compact.

A residence time of the moist granules in the rounder is preferably from 5 to 180 s, in particular from 15 to 80 s. When performing the The manufacturing method according to the invention also has a peripheral speed the rotating base plate of at least 10 m / s, in particular of at least 15 m / s was found to be favorable. It is also preferred a moisture content of 5 to 20% by weight, in particular 10 to 15% by weight of the wet granules before rounding.

All substances known today for this purpose can be used as bleach activators or mixtures of substances are used. For the sake of completeness, the substances are summarized again as follows: suitable bleach activators for per compounds are accordingly O- and / or N-acylated compounds such as Pentaacetylglucose (PAG), Pentapropionylglucose (PPG), Tetraacetylethylenediamine (TAED), tetraacetylglycoluril (TAGU), triacetylethanolamine (TAEA), acylated triazine derivatives such as 1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine (DADHT), carboxylic anhydrides, such as succinic, benzoic or phthalic anhydride, Salts of mixed anhydrides, such as sodium or Magnesium diacetyl phosphate (NADAP or MGDAP), phenol esters such as p-Carboxylphenylacetat, p-Sulfonylphenylacetat, as well as other phenol esters with an anionic substituent on the phenyl radical.

The bleach activator used is preferably tetraacetylethylene diamine (TAED).

A granulation aid is preferably used in the process according to the invention Compound from the class of water-soluble cellulose ethers, starch and Starch ether used. Carboxymethyl cellulose is preferred here, in particular Sodium carboxymethyl cellulose. Further information on the granulation aids can be found in DE 30 11 998 C2, here to supplement the disclosure is expressly referred to.

During granulation in the mixing granulator can be used as a granulation aid also additives such as oxidation-stable complexing agents and stabilizers for Per compounds and / or other components of detergents and cleaning agents admixed or introduced via the aqueous granulating liquid. Examples of these are salts of polyphosphonic acids, such as 1-hydroxyethane-1,1-diphosphonate, Ethylene diamine tetramethylene phosphonate and diethylene triamine pentamethylene phosphonate, each in the form of the sodium salt. The share of Phosphonate additives are preferably 3 to 10% by weight and especially preferably 5 to 8 wt .-%, each based on the dried Bleach activator granules. The preferred amount of phosphonate is not here the liquid granulation aid, but related to the finished product, since it it has been found that the phosphonate concentration in the granulation aid, but the absolute amount of phosphonate sprayed on is essential. The advantage lies in the enhancement of the rounding and compacting effect and thus also in an increase in the bulk density of the dried bleach activator granules. One with the bleach activator granules according to the invention mixed universal detergent in this case contains about 0.5 wt .-% of this Additions.

In a further advantageous embodiment of the invention The method is used in the granulating and / or compacting step as a granulating aid a solution of a stabilizer for carboxymethyl cellulose free Per compounds, in particular a salt of a polyphosphonic acid, and optionally other components of detergents and cleaning agents. In particular, it is proposed that the granulation aid in addition to water contains only polyphosphonate.

In the process according to the invention, it is particularly preferred if one finely divided solid (powder) the moist granules moving in the fillet admits. The powdering in the fillet leads to a better movement of the moist granules and thus for improved compaction and rounding.

The powder preferably contains one or more constituents of washing and / or cleaning agents and in particular zeolite NaA.

It is particularly preferred if the powder consists of fine parts of the finished product Bleach activator granules. These fines fall when the dried product regularly and are usually used in the process returned by these fine fractions that in the first process step, the Granulating step, powdered batch used are added. in the Contrary to this procedure, the fines are inventively thus fed to the second process step.

It has proven to be advantageous if 1 to 25% by weight, preferably 3 to 15% by weight, powder, based on the dried finished bleach activator granules, admits the moist granules moving in the fillet.

To optimize the rounding and in particular to achieve more advantageous Surface effects, e.g. B. the formation of a particularly effective barrier layer against migrating water and / or an increase in whiteness the additives mentioned above, in particular an aqueous solution of a Granulation aid, or other ingredients of washing and cleaning agents when rounding the moist granules added simultaneously, e.g. B. injected become.

The water content of the granules is then preferably less than 3 less than 2 and in particular less than 1.5 wt .-% lowered. The Extracting the excess water can be done by drying with heat take place, the temperature of the granules expediently not 80 ° C. exceeds and is below the melting temperature of the bleach activator. Dryers that do not adversely affect the granular structure of the product are suitable change, for example tray dryers, vacuum and in particular fluid bed dryers.

The invention also relates to a storage-stable, bleach activators and a granulate containing granules, prepared according to the above mentioned method by a bulk density of at least 580 g / l, in particular at least 630 g / l is marked.

The granules according to the invention show the advantages already mentioned and surprising Effects, the improved degree of whiteness of the granules and the high storage stability of the finished with these granules by mixing Detergent and cleaning agent end products are particularly highlighted here should be.

The granulate according to the invention is preferably characterized by a Content of 70 to 97% by weight, preferably 80 to 95% by weight, of bleach activator, in particular TAED, 0.5 to 10% by weight of a granulation aid, in particular Carboxymethyl cellulose and optionally other components of washing and Detergents that are at least as well redispersible as those mentioned Components are. The possibility of a particularly high content is advantageous Bleach activator. In a further advantageous embodiment, this contains Granules according to the invention also 0 to 15 wt .-%, preferably 4 to 8 % By weight of a stabilizer for per compounds, in particular a salt Polyphosphonic acid.

The granulate according to the invention is further characterized in that it has a Whiteness measured as L * value, determined with the Minolta colorimeter Chroma meter CR, can have at least 80.

Finally, the subject of the invention also includes those with the invention Granules produced by mixing detergent and cleaning agent end products, and in particular products in which the Main ingredients containing granules in the form of uniform, through Extruding a homogeneous premix and cutting the obtained one Strangs, so produced by the above-mentioned extrusion process and to which the granules according to the invention have been mixed.

Examples

Exemplary embodiments of the invention are described in more detail below.

example 1

Tetraacetylethylenediamine (TAED) with a medium Grain size from 0.01 to 0.8 mm used. The grain content between 0.8 and 1.6 mm was 5% by weight, the proportion below 0.01 mm was 10% by weight.

1500 kg / h of the powdery bleach activator with 43 kg / h of sodium carboxymethyl cellulose (CMC) and 500 kg / h of fine return content with grain sizes of less than 0.4 mm mixed and sprayed simultaneously with an aqueous 32% sodium diethylenetriamine pentamethylene phosphonate solution (Na ₇ DTPMPA, commercially available product "Dequest 2066"). The term “fine return fraction” is to be understood as meaning the fine fractions sieved off after drying, which in this example are returned to the first process step. The mixing and uniform distribution took place in an annular layer formed by the tools on the rapidly rotating shaft. Granules were already formed in this mixer.

The product then went through a second cylindrical mixer, however horizontal axis and and was brought there into the desired Granulafform.

The resulting wet granules with a water content of 11.2 wt .-% was then one of two rounders of the type connected in series "Marumerizer" added to existing rounding cascade.

In each of the cylindrical apparatuses with vertical longitudinal axes, they also rotated Protrusions and recesses provided base plate with a peripheral speed of 18 m / s. Between the inner wall of the cylindrical housing and cold air was blown into the edge of the rotating plate. The granules collected on the edge of the base plate due to the centrifugal force. This very dense ring-shaped rotating granulate layer was created by the bottom blown cold air in a circular motion around the ring axis in addition to Movement of the ring offset around the cylinder axis of the apparatus.

After an average residence time of the moist granules in the rounders of 45 The granules were discharged and placed in a fluidized bed dryer Product temperature of 75 ° C warmed to a residual water content of 0.6% by weight dried.

85 Gew.-% TAED

7,6 Gew.-% Phosphonat

2,55 Gew.-% Carboxymethylcellulose

4,8 Gew.-% Salze und Wasser.

65 Gew.-% des Granulates wiesen eine Korngröße von 0,4 bis 2,0 mm auf. Der Rest enthielt Grob- und Feinstanteile, die abgesiebt und zurückgeführt (recyclet) wurden.The composition of the granules obtained was

85 wt% TAED

7.6% by weight phosphonate

2.55% by weight carboxymethyl cellulose

4.8% by weight of salts and water.

65% by weight of the granules had a grain size of 0.4 to 2.0 mm. The rest contained coarse and very fine fractions, which were screened off and recycled.

The activator granules had a bulk density of 660 g / l. Whiteness L *, determined with the color measuring device Minolta Chroma-Meter CR, was 84, so a significantly higher value than with the known activator granules which is well below 80.

The activator granules according to the invention were developed in accordance with DE 39 26 253 A1 manufactured, the main ingredients of a universal detergent containing extrudates mixed to the resulting bulk density as well as the Check storage stability. This extrudate contained 25% by weight sodium perborate monohydrate. 67% by weight of the extrudate mentioned was mixed with 8.5% by weight of the activator granules according to the invention and with further, conventional ones Detergent components, e.g. B. enzymes, to the finished detergent product mixed. For comparison, a mixture with according to DE 30 11 998 C2 prepared granules made that had a bulk density of 530 g / l. Compared to the final detergent product with the known granules a bulk density increase of about 30 g / l was found. From the difference of Bulk weights of the activator granules, namely 130 g / l and their share of 8.5 In theory, however, there is only an increase in the weight of the end product of approximately 10 g / l. This disproportionate increase in the bulk density when using the activator granules according to the invention is surprising.

Both blends were subjected to a storage test at 60 ° C. The camp trial was in a drying cabinet at a relative humidity of 15 % performed. Mixing with the known activator granules showed a decrease in the active oxygen content from the initial 1.72% by weight to 1.39 % By weight after 8 days of storage. When mixed with the invention Activator granules also decreased the active oxygen content after 8 days Storage time at 60 ° C from an initial 1.75 wt .-% to 1.54 wt .-%. This significantly increased storage stability is another surprising effect of activator granules according to the invention or the detergent end products mixed therewith.

Example 2

In a Schugi mixer (type "Flexomix") 1500 kg / h TAED powder and 800 kg / h fines <0.4 mm, which are constantly returned in the process, were sprayed with 416 kg / h "Dequest 2066" (32 % aqueous solution) granulated. After the moist product had then been passed through a "CB" mixer from Gebr. Lödige, the moist granules were rounded in a rounder cascade consisting of two rounders with a respective disk diameter of 0.7 m at speeds of 300 rpm. The product was dried in a vortex dryer from Haag at product temperatures of 65 - 75 ° C and residual water contents of <1%. The screened finished product had a bulk density of 590 g / l and the following grain composition: > 1.6 0.8 - 1.6 0.4-0.8 0.2 - 0.4 <0.2 mm 3.4 33.4 53.9 8.9 0.4%

In a mixture of 8.5% by weight with those prepared according to DE 39 26 253 A1, the main ingredients of an extrudate containing universal detergent were by 20 g / l higher bulk weights, based on the finished product than at Use of unrounded TAED granules, manufactured according to DE 30 11 998 C2.

Examples 3a and 3b

In these examples, the granulation was carried out with CMC, but without the addition of phosphonate. Towards the end of the rounding process, the rounding became Powder materials, as described below, are added.

Example 3a

Moist granules were produced in batches in the FKM5D mixer from Gebr. Lödige. approach TAED crystalline 1425 g CMC ("Tylose CR1500P") 75 g water 225 g

The mixing time with the rotating cutter head was 35 s after adding water. The The moist granules obtained were in a rounder with a diameter of Rounding disc of 50 cm at a speed of 450 1 / min for 40 s rounded. After a rounding time of 15 s, 45 g of zeolite NaA ("Wessalith P" of Degussa) added in the fillet.

Example 3b

The approach and the procedure corresponded to example 3a, but were followed 15 s rounding time instead of zeolite NaA 150 g TAED fines <0.4 mm added to the production plant. After drying and sieving fell Fine particles in the same order of magnitude again.

The product data of Examples 3a and 3b after drying with hot air in a fluidized bed to a product temperature of 70 ° C. and a residual water content of <1% and a screening of the return proportions> 1.6 and finer 0.4 mm are listed in the table below. example > 1.6 0.8 - 1.6 0.4-0.8 <0.4 Sg ΔSG 3a 0.5 34.8 62.6 2.1 597 20th 3b 1.2 49.1 48.1 1.6 644 30th

Mean

Sg

Bulk density in g / l

ΔSG

Bulk density increase in g / l in a mixture of 8.5% by weight with the above extrudate compared to the use of unrounded TAED granules of the type mentioned above.

The advantages of powdering the moist granules in the fillet with powder Bleach activator can be clearly seen in the table.

Claims (22)

1. A process for the production of storage-stable granules containing bleach activators as a component of a laundry detergent or dishwashing detergents by granulation of a moist powder-form mixture of a powder-form bleach activator, a powder-form granulation aid and an aqueous solution of the same and/or a different granulation aid or an aqueous solution of other active substances of laundry or dishwashing detergents or water by agglomerating the moist particles in a mixer/granulator and then drying the moist granules and optionally removing oversize particles and fines by sieving, characterized in that, before they are dried to the required residual moisture content, the moist granules are delivered to another apparatus (spheronizer) where they rubbed against one another and against the wall and/or base of the spheronizer and, at the same time, so highly compacted that, after drying, the granules have a bulk density of at least 580 g/l and, more particularly, at least 630 g/l.
2. A process as claimed in claim 1, characterized in that the moist granules are rubbed against one another and compacted in a spheronizer with a rotating horizontal baseplate while a working gas, more especially cold air, is blown in from below between the housing wall and the edge of the baseplate.
3. A process as claimed in any of the preceding claims, characterized in that the moist granules are rubbed against one another and compacted in several spheronizers arranged in tandem.
4. A process as claimed in any of the preceding claims, characterized by a residence time of the moist granules in the spheronizer of 5 to 180 s and more particularly 15 to 80 s.
5. A process as claimed in any of claims 2 to 4, characterized by a peripheral speed of the rotating baseplate of at least 10 m/s and, more particularly, at least 15 m/s.
6. A process as claimed in any of the preceding claims, characterized by a moisture content of 5 to 20% by weight and, more particularly, 10 to 15% by weight of the moist granules before spheronizing.
7. A process as claimed in any of the preceding claims, characterized in that tetraacetyl ethylenediamine (TAED) is used as the bleach activator.
8. A process as claimed in any of the preceding claims, characterized in that carboxymethyl cellulose, more especially sodium carboxymethyl cellulose, is used as the granulation aid.
9. A process as claimed in any of the preceding claims, characterized in that a solution of a stabilizer for per compounds, more especially a salt of a polyphosphonic acid and/or a solution of other detergent ingredients is used as the granulation aid.
10. A process as claimed in any of the preceding claims, characterized in that the granulation aid contains 3 to 10% by weight and preferably 5 to 8% by weight, based on the dried bleach activator granules, of the salt of a polyphosphonic acid.
11. A process as claimed in any of claims 1 to 7, characterized in that a solution of a stabilizer for per compounds, more especially a salt of a polyphosphonic acid,
12. A process as claimed in the preceding claim, characterized in that, apart from water, the granulation aid contains only polyphosphonate.
13. A process as claimed in any of the preceding claims, characterized in that a fine-particle solid (powder) is added to the moist granules moving around in the spheronizer.
14. A process as claimed in the preceding claim, characterized in that the powder contains one or more ingredients of detergents and/or cleaners and, more particularly, zeolite NaA.
15. A process as claimed in claim 13 or 14, characterized in that the powder consists of fine particles of the final bleach activator granules.
16. A process as claimed in any of claims 13 to 15, characterized in that 1 to 25% by weight and preferably 3 to 15% by weight of powder, based on the dried final bleach activator granules, is added to the moist granules moving around in the spheronizer.
17. Storage-stable granules containing bleach activators and a granulation aid produced by the process claimed in any of the preceding claims and having a bulk density of at least 580 g/l and, more particularly, at least 630 g/l.
18. Granules as claimed in the preceding claim, characterized by a content of 70 to 97% by weight and preferably 80 to 95% by weight of bleach activator, more especially TAED, 0.5 to 10% by weight of a granulation aid, more especially carboxymethyl cellulose, and optionally other ingredients of detergents which are at least comparable in their redispersibility with the ingredients mentioned.
19. Granules as claimed in claim 17, characterized by a content of 70 to 97% by weight and preferably 80 to 95% by weight of bleach activator, more especially TAED, 0.5 to 10% by weight of a granulation aid, more especially carboxymethyl cellulose, 0 to 15% by weight and preferably 4 to 8% by weight of a stabilizer for per compounds, more especially a salt of a polyphosphonic acid, and optionally other ingredients of detergents which are at least comparable in their redispersibility with the ingredients mentioned.
20. Granules as claimed in any of claims 17 to 19, characterized by a whiteness, measured as the L* value by the Minolta colour measuring method, of at least 80.
21. Detergents containing the granules claimed in any of claims 17 to 20.
22. Detergents in the form of uniform granules which have been produced by extruding a homogeneous compound and cutting up the strand obtained and in which the granules claimed in claims 17 to 20 have been incorporated.