Title:
Method for producing coated bleach activator granules
Kind Code:
A1


Abstract:
The present invention relates to methods for coating bleach activator-containing granules by treatment with an acidic aqueous consolidating solution, comprising polymeric polycarboxylate and/or alkali metal phosphonate as coating and consolidation active ingredient, with simultaneous drying in a fluidized-bed apparatus.



Inventors:
Assmann, Georg (Junchen, DE)
Blochwitz, Olaf Joachim (Genthin, DE)
Speckmann, Horst-dieter (Dusseldorf, DE)
Poethkow, Jorg (Neuss, DE)
Middelhauve, Birgit (Monheim, DE)
Blasey, Gerhard (Dusseldorf, DE)
Application Number:
10/861188
Publication Date:
12/09/2004
Filing Date:
06/04/2004
Assignee:
ASSMANN GEORG
BLOCHWITZ OLAF JOACHIM
SPECKMANN HORST-DIETER
POETHKOW JORG
MIDDELHAUVE BIRGIT
BLASEY GERHARD
Primary Class:
International Classes:
C11D3/26; C11D3/37; C11D3/39; C11D3/395; C11D7/08; C11D7/26; C11D7/32; C11D7/36; C11D7/54; C11D11/00; C11D17/00; C11D17/06; (IPC1-7): D06L1/00
View Patent Images:
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20060270582Polymer-containing detergent compositions and their useNovember, 2006Boeckh et al.
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20100040785Method For Dry-Cleaning LeatherFebruary, 2010Lang
20090069210COLOUR-PROTECTING LAUNDRY DETERGENT COMPOSITIONMarch, 2009Penninger et al.
20090143267Packaging for high moisture bar soapJune, 2009Zhang et al.
20060058206Aqueous activated components conveyed in a non-aqueous carrier systemMarch, 2006Walls et al.
20090191248HAND HEALTH AND HYGIENE SYSTEM FOR HAND HEALTH AND INFECTION CONTROLJuly, 2009Hoffman et al.
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Primary Examiner:
DELCOTTO, GREGORY R
Attorney, Agent or Firm:
BakerHostetler (Philadelphia, PA, US)
Claims:

What is claimed:



1. A method for producing a bleach-activator-coated particulate preparation, comprising a compound according to formula (I): 2embedded image wherein: R1 is —H, —CH3, optionally substituted (C2-C24)-alkyl radical, optionally substituted (C2-C24)-alkenyl radical, optionally substituted alkyl radical containing a (C1-C24)-alkyl group, or optionally substituted alkenylaryl radical containing a (C1-C24)-alkyl group; R2 and R3 are independently —CH2—CN, —CH3, —CH2—CH3, —CH2—CH2—CH3, —CH(CH3)—CH3, —CH2—OH, —CH2—CH2—OH, —CH(OH)—CH3, —CH2—CH2—CH2—OH, —CH2—CH(OH)—CH3, —CH(OH)—CH2—CH3, or —(CH2CH2—O)nH; R4 and R5 are independently —H, —CH3, optionally substituted (C2-C24)-alkyl radical, optionally substituted (C2-C24)-alkenyl radical, optionally substituted alkyl radical containing a (C1-C24)-alkyl group, optionally substituted alkenylaryl radical containing a (C1-C24)-alkyl group, CH2—CN, —CH2—CH3, —CH2—CH2—CH3, —CH(CH3)—CH3, —CH2—OH, —CH2—CH2—OH, —CH(OH)—CH3, —CH2—CH2—CH2—OH, —CH2—CH(OH)—CH3, —CH(OH)—CH2—CH3, or —(CH2CH2—O)nH; n is an integer of 1, 2, 3, 4, 5 or 6; X(−) is a charge-balancing anion; wherein said particulate is produced by the steps of: a) spraying said compound of formula (I) onto a carrier material to produce a carrier-coated-compound, and b) drying said carrier-coated-compound in a fluidized-bed apparatus with an acidic aqueous solution comprising a coating and consolidation active ingredient; or c) mixing said compound of formula (I) with an organic or inorganic carrier material in an aqueous solution, and d) optionally removing the aqueous solvent under reduced pressure and elevated temperature.

2. The method of claim 1, wherein R1, R2, and R3 are the same.

3. The method of claim 1, wherein R1, R2, and R3 are —CH3.

4. The method of claim 1, wherein 1 or 2 of said R1, R2, and R3 radicals are —CH3 and at least one of said R1, R2, and R3 radicals contains 2 or more carbon atoms.

5. The method of claim 1, wherein X(−) is halide, nitrate, hydroxide, phosphate, hydrogenphosphate, dihydrogenphosphate, pyrophosphate, metaphosphate, hexafluorophosphate, carbonate, hydrogencarbonate, sulfate, hydrogensulfate, (C1-C20)-alkyl sulfate, (C1-C20)-alkylsulfonate, optionally (C1-C18)-alkyl-substituted arylsulfonate, chlorate, perchlorate, an anion of (C1-C24)-carboxylic acid, or combinations thereof.

6. The method of claim 1, wherein X(−) is chloride, sulfate, hydrogensulfate, methosulfate, ethosulfate, (C12-C18)-alkyl sulfate, (C12-C16)-alkyl sulfate, or (C13-C15)-alkyl sulfate, lauryl sulfate, dodecylbenzenesulfonate, toluenesulfonate, cumenesulfonate, xylenesulfonate or combinations thereof.

7. The method of claim 1, wherein said particulate has a diameter in the range of from about 0.4 mm to about 3 mm.

8. The method of claim 1, wherein said carrier material is alkali metal cumenesulfonate, surfactant, organic acid, organic polymer, alkali metal carbonate, alkali metal sulfate, alkali metal hydrogensulfate, alkali metal hydrogencarbonate, alkali metal phosphate, alkali metal dihydrogenphosphate, dialkali metal hydrogenphosphate, alkali metal silicate, silicas, silica gel, silica clay, or combinations thereof.

9. The method of claim 1, wherein the internal surface area of said carrier material is in the range of from about 10 m2/g to about 500 m2/g.

10. The method of claim 1, wherein said carrier material particle size in the range of from about 100 μm to about 1.5 mm.

11. The method of claim 1, further comprising the steps of: e) preparation of an aqueous solution comprising cationic nitrile and optionally alkali metal cumenesulfonate; f) optional adjustment of the solution to an acidic pH; g) atomization and drying of the solution in a fluidized-bed apparatus; h) optional powdering of the resulting primary granules in the fluidized bed; i) spraying the resulting optionally powdered granules with an aqueous consolidation and coating solution, and simultaneous drying in the same or optionally in a downstream second fluidized-bed apparatus; j) discharging the granules from the fluidized-bed apparatus and optionally separating the granules into acceptable granules and coarse/fine granules; k) optionally returning fine granules and/or ground coarse granules to the fluidized bed in step g); and l) optionally returning fine granules and/or ground coarse granules to the powdering step of step h).

12. The method of claim 11, wherein said cationic nitrile is present in a range of from about 10% by weight to about 90% by weight.

13. The method of claim 11, wherein said cationic nitrile is present in a range of from about 15% by weight to about 50% by weight.

14. The method of claim 11, wherein said alkali metal cumenesulfonate is sodium cumenesulfonate.

15. The method of claim 11, wherein the pH is adjusted to an acidic value by the addition of sulfuric acid, citric acid or combinations thereof.

16. The method of claim 11, wherein the pH is in the range of from about 4 to about 4.4.

17. The method of claim 11, wherein said primary granules are powdered with silica, zeolite, alkali metal cumenesulfonate, or combinations thereof.

18. The method of claim 11, wherein said primary granules are powdered with Na cumenesulfonate.

19. The method of claim 11, wherein said aqueous consolidation and coating solution comprises polymeric polycarboxylate, phosphonic acid, alkali metal phosphonate, or combinations thereof.

20. The method of claim 11, wherein said polymeric polycarboxylate is polymerization products of acrylic acid, methacrylic acid, maleic acid, or copolymers of at least two of the polymerization products, in at least partially neutralized form.

21. The method of claim 11, wherein said granules are coated with an amount of said aqueous consolidation and coating solution in the range of from about 1% by weight of granules to about 25% by weight of granules.

22. The method of claim 11, wherein said granules are coated with an amount of said aqueous consolidation and coating solution in the range of from about 2% by weight of granules to about 15% by weight of granules.

23. The method of claim 11, wherein said granules are separated by sieving.

24. The method of claim 11, wherein the bulk density of the coated particulate preparation is in the range of from about 300 g/l to about 1000 g/l.

25. The method of claim 11, wherein the bulk density of the coated particulate preparation is in the range of from about 400 g/l to about 800 g/l.

26. The method of claim 11, wherein the proportion of compound according to formula (I) in the coated particulate preparation is in the range of from about 10% by weight to about 90% by weight.

27. The method of claim 11, wherein the proportion of compound according to formula (I) in the coated particulate preparation is in the range of from about 15% by weight to about 50% by weight.

28. A particulate detergent or cleaner prepared by the method of claim 1.

29. A particulate detergent or cleaner prepared by the method of claim 11.

30. The particulate detergent or cleaner of claim 28, wherein said coated particulate is present in a range of from about 0.1% by weight to about 10% by weight.

31. The detergent or cleaner of claim 28, wherein said coated particulate is present in a range of from about 0.2% by weight to about 7% by weight.

32. The detergent or cleaner of claim 29, wherein said coated particulate is present in a range of from about 0.1% by weight to about 10% by weight.

33. The detergent or cleaner of claim 29, wherein said coated particulate is present in a range of from about 0.1% by weight to about 10% by weight.

Description:

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of PCT/EP02/13127 filed Nov. 22, 2002, which claims the benefit of DE 101 59 388.0, filed Dec. 4, 2001, the complete disclosures of which are hereby incorporated by reference in their entirety.

FIELD OF THE INVENTION

[0002] The invention relates to a method for coating bleach activator-containing granules by treatment with an acidic aqueous consolidating solution, which comprises polymeric polycarboxylate and/or alkali metal phosphonate as coating and consolidation active ingredient, with simultaneous drying in a fluidized-bed apparatus.

BACKGROUND OF THE INVENTION

[0003] As well as comprising ingredients which are indispensable for the washing process, such as surfactants and builder materials, detergents and cleaners usually comprise further constituents which can be summarized under the term washing auxiliaries and include various groups of active ingredients, such as foam regulators, graying inhibitors, bleaches and color transfer inhibitors. Such auxiliaries also include substances which aid the surfactant performance as a result of oxidative degradation of soilings located on the textile or those in the liquor. Analogous statements also apply to cleaners for hard surfaces. For example, inorganic peroxygen compounds, in particular hydrogen peroxide and solid peroxygen compounds which dissolve in water to liberate hydrogen peroxide, such as sodium perborate and sodium carbonate perhydrate, have been used for a long time as oxidizing agents for disinfection and bleaching purposes. The oxidative effect of these substances greatly depends on the temperature in dilute solutions; thus, for example, with H2O2 or sodium perborate in alkaline bleaching liquors, sufficiently rapid bleaching of soiled textiles only takes place at temperatures above about 60° C. At lower temperatures it is possible to improve the oxidative effect of the inorganic peroxygen compounds by adding so-called bleach activators, for which numerous proposals, primarily from the classes of substance of N- or O-acyl compounds, for example polyacylated alkylenediamines, in particular tetraacetylethylenediamine, acylated glycolurils, in particular tetraacetylglycoluril, N-acylated hydantoins, hydrazides, triazoles, hydrotriazines, urazoles, diketopiperazines, sulfurylamides and cyanurates, and also carboxylic anhydrides, in particular phthalic anhydride, carboxylic esters, in particular sodium nonanoyloxybenzenesulfonate, sodium isononanoyloxybenzenesulfonate and acylated sugar derivatives, such as pentaacetylglucose, have become known in the literature. The addition of these substances can increase the bleaching action of aqueous peroxide liquors such that even at temperatures below 60° C. essentially the same effects arise as with the peroxide liquor on its own at 95° C.

[0004] European patent application EP 0 464 880 discloses bleach-boosting cationic nitriles of the general formula R′R″R′″N+—CR1R2—CN X, in which R1 and R2 are hydrogen or a substituent with at least one carbon atom, R′ is a (C1-C24)-alkyl, alkenyl or alkyl ether group or a group —CR1R2—CN, and R″ and R′″ is in each case a (C1-C24)-alkyl or hydroxyalkyl group, and the counteranion X is an organic sulfonate, an organic sulfate or a carboxylate.

[0005] International patent application WO 98/23719 discloses that compounds of the general formula R1R2R3N+CH2CN X, in which R1, R2 and R3, independently of the others, is an alkyl, alkenyl or aryl group having 1 to 18 carbon atoms, where the groups R2 and R3 may also be part of a heterocycle including the N atom and optionally further heteroatoms, and X is a charge-balancing anion, can be used as activators for, in particular, inorganic peroxygen compounds in aqueous dishwashing solutions. This provides an improvement of the oxidative and bleaching effect in particular of inorganic peroxygen compounds at low temperatures below 80° C., in particular in the temperature range from about 15° C. to 55° C. However, particularly in combination with further ingredients of detergents and cleaners, the cationic nitriles are normally not very storage-stable and, in particular, are sensitive to moisture.

[0006] International patent application WO 00/50556 discloses the production of solid preparations which comprise cationic nitrile and solid carrier material, by a vacuum steam-drying process in a mixer.

SUMMARY OF THE INVENTION

[0007] It was an object of the present invention to provide a method which allows granules which comprise a cationic nitrile to be incorporated into particulate detergents and cleaners such that the cationic nitrile suffers the smallest possible loss in bleach-activating effect even after storage. It has now been found that the production of preparations which satisfy this requirement is possible by a fluidized-bed coating method. This allows a protective coating to be applied to the granules without having to accept a decrease in bleach activator effect.

[0008] These and other aspects of the invention will become more apparent from the detailed description and claims.

DETAILED DESCRIPTION OF THE INVENTION

[0009] In one embodiment, the present invention provides methods for production of a bleach-activator-coated particulate preparation comprising a compound according to formula (I): 1embedded image

[0010] wherein:

[0011] R1 is —H, —CH3, optionally substituted (C2-C24)-alkyl radical, optionally substituted (C2-C24)-alkenyl radical, optionally substituted alkyl radical with a (C1-C24)-alkyl group, optionally substituted alkenylaryl radical with a (C1-C24)-alkyl group;

[0012] R2 and R3 are independently —CH2—CN, —CH3, —CH2—CH3, —CH2—CH2—CH3, —CH(CH3)—CH3, —CH2—OH, —CH2—CH2—OH, —CH(OH)—CH3, —CH2—CH2—CH2—OH, —CH2—CH(OH)—CH3, —CH(OH)—CH2—CH3, or —(CH2CH2—O)nH;

[0013] n is an integer of 1, 2, 3, 4, 5 or 6;

[0014] R4 and R5 are independently —H, —CH3, optionally substituted (C2-C24)-alkyl radical, optionally substituted (C2-C24)-alkenyl radical, optionally substituted alkyl radical with a (C1-C24)-alkyl group, optionally substituted alkenylaryl radical with a (C1-C24)-alkyl group, —CH2—CN, —CH2—CH3, —CH2—CH2—CH3, —CH(CH3)—CH3, —CH2—OH, —CH2—CH2—OH, —CH(OH)—CH3, —CH2—CH2—CH2—OH, —CH2—CH(OH)—CH3, —CH(OH)—CH2—CH3, or —(CH2CH2—O)nH;

[0015] X(−) is a charge-balancing anion; and

[0016] wherein said compound according to formula (I) is present in solid, in particular pulverulent, form, is sprayed, if desired in a mixture with binders and/or a solid filler or in the form of preprepared granules, with simultaneous drying in a fluidized-bed apparatus with an acidic aqueous solution which comprises, as coating and consolidation active ingredient, polymeric polycarboxylate and/or phosphonic acid or alkali metal phosphonate.

[0017] By the present invention, the bleach activator according to formula (I) or a particle comprising it can be completely coated with a coating material. Furthermore, if the solution comprising polymeric polycarboxylate and/or phosphonic acid or alkali metal phosphonate is used, an increase in the granule strength of the bleach activator particle is observed.

[0018] Compounds according to formula I can be produced by known processes or in accordance with these, as have been published, for example, in said patent literature or by Abraham in Progr. Phys. Org. Chem. 11 (1974), p. 1 ff, or by Arnett in J. Am. Chem. Soc. 102 (1980), p. 5892 ff.

[0019] The terms “optionally substituted (C2-C24)-alkyl” and “optionally substituted (C2-C24)-alkenyl radical”, as used herein, includes those alkyl or alkenyl radicals that are optionally substituted with at least one substituent selected from the group comprising —Cl, —Br, —OH, —NH2, and —CN.

[0020] The term “optionally substituted alkenylaryl radical”, as used herein, includes those alkenylaryl radicals that are optionally substituted with a (C1-C24)-alkyl group and which further contain at least one substitutent on the aromatic ring.

[0021] Preference is given to the use of compounds according to formula I in which R1, R2 and R3 are identical. Of these, preference is given to those compounds in which said radicals are methyl groups. On the other hand, preference is also given to those compounds in which at least 1 or 2 of said radicals are methyl groups and the others have two or more carbon atoms.

[0022] The anions X(−) include, in particular, the halides, such as chloride, fluoride, iodide and bromide, nitrate, hydroxide, phosphate, hydrogenphosphate, dihydrogenphosphate, pyrophosphate, metaphosphate, hexafluorophosphate, carbonate, hydrogencarbonate, sulfate, hydrogensulfate, (C1-C20)-alkyl sulfate, (C1-C20)-alkylsulfonate, optionally (C1-C18)-alkyl-substituted arylsulfonate, chlorate, perchlorate, or the anions of (C1-C24)-carboxylic acids, such as formate, acetate, laurate, benzoate or citrate, or combinations thereof.

[0023] Preference is given to compounds according to formula I in which X(−) is chloride, sulfate, hydrogensulfate, ethosulfate, (C2-C18)—, (C12-C16)-or, (C13-C15)-alkyl sulfate, lauryl sulfate, dodecylbenzenesulfonate, toluenesulfonate, cumenesulfonate, xylenesulfonate or methosulfate, or combinations thereof. Toluenesulfonate, or cumenesulfonate, is understood here as meaning the anion of the ortho-, meta- or para-isomers of methylbenzenesulfonic acid, or isopropylbenzenesulfonic acid, respectively, and combinations thereof. para-Isopropyl-benzenesulfonic acid is particularly preferred.

[0024] The compound according to general formula (I) can be used as starting material in the coating method according to the invention in solid form as it is or formulated in particulate form, i.e. applied to an organic and/or inorganic carrier material. In this connection, the compound according to formula (I) can be applied to the carrier material by stirring the carrier material into a solution of the compound according to formula (I), as formed during the course of its production, and stripping off the optionally aqueous solvent under reduced pressure, if desired at elevated temperature. However, it is also possible to spray the solution of the compound according to formula (I) onto the carrier material and, during this operation or optionally subsequently to it, subject it to a drying process. The coating of the bleach activator granules produced according to the process disclosed in German patent applications DE 197 40 668 or DE 197 40 671 is also possible by means of the method according to the invention and represents a preferred embodiment of the method according to the invention. It is preferable for the particles produced by the formulating process to have a diameter in the range from about 0.4 mm to about 3 mm. Suitable carrier materials are all substances which do not interact in an unreasonably negative manner with the compound according to formula (I), for example alkali metal cumenesulfonate, surfactants, organic acids and polymers, alkali metal carbonates, alkali metal sulfates, alkali metal hydrogensulfates, alkali metal hydrogencarbonates, alkali metal phosphates, alkali metal dihydrogenphosphates, dialkali metal hydrogenphosphates and alkali metal silicates and mixtures thereof. Preference is given to using those carrier materials whose internal surface area is in the range from about 10 m2/g to about 500 m2/g, in particular from about 100 m2/g to about 450 m2/g. The silicatic carrier materials particularly suitable for the purposes of the present invention include, for example, alkali metal silicates, and also silicas, silica gels and clays, and mixtures thereof. However, the carrier material is preferably free from zeolites. Besides the silicate component, the silicate-containing carrier material optionally comprises further particulate inert constituents do not unreasonably impair the stability of the compounds according to formula (I). Silicas which have been produced by a thermal process (flame hydrolysis of SiCl4) (so-called fumed silicas), are just as suitable for use as silicas produced by wet methods. Silica gels are colloidal silicas with elastic to solid consistency and a largely loose pore structure, resulting in a high liquid-uptake capacity. They can be produced by the action of mineral acids on waterglass. Clays are naturally occurring crystalline or amorphous silicates of aluminum, iron, magnesium, calcium, potassium and sodium, for example kaolin, talc, pyrophyllite, attapulgite, sepiolite, montmorillionate and bauxite. The use of aluminum silicate as a carrier material or as a component of a carrier material mixture is also possible. The carrier material preferably has particle sizes in the range from about 100 μm to about 1.5 mm.

[0025] In a further preferred embodiment of the invention, the procedure involves carrying out the steps of:

[0026] a) preparation of an aqueous solution, comprising cationic nitrile, preferably in amounts of from about 10% by weight to about 90% by weight, in particular from about 15% by weight to about 50% by weight, and optionally alkali metal cumenesulfonate, in particular sodium cumenesulfonate,

[0027] b) optional adjustment of the solution to an acidic pH, in particular by adding sulfuric acid and/or citric acid

[0028] c) atomization and drying of the solution in a fluidized-bed apparatus,

[0029] d) optional powdering of the primary granules obtained in this way using silica, zeolite and/or alkali metal cumenesulfonate, in particular Na cumenesulfonate, in the fluidized bed, and spraying the resulting optionally powdered granules with the aqueous consolidation and coating solution with simultaneous drying in the same or optionally a downstream second fluidized-bed apparatus. Thereafter, the granules can be discharged from the fluidized-bed apparatus and, where necessary, be separated into acceptable granules and coarse/fine granules, in particular by sieving. Where necessary, this may be followed by returning fine granules and/or ground coarse granules to the fluidized bed in step c) and/or returning fine granules and/or ground coarse granules to the powdering step d).

[0030] The coated bleach activator granules obtainable by the method according to the invention, or the acceptable granule fraction thereof, preferably has average particle diameters in the range from about 0.2 mm to about 2.5 mm, in particular in the range from about 0.4 mm to about 2.0 mm. Its bulk density is preferably in the range from about 300 g/l to about 1000 g/l, in particular in the range from about 400 g/l to about 800 g/l. The proportion of compound according to formula (I) is preferably in the range from about 10% by weight to about 90% by weight, in particular from about 15% by weight to about 50% by weight. It is preferably used for producing particulate detergents or cleaners.

[0031] Fluidized-bed devices which can be used in a method according to the invention are known, for example, from European patent specification EP 0 603 207 B1 or German patent application DE 197 50 424. In order to further reduce the possibility of the granules falling through the openings in the inflow base, which would result in them coming into contact with surfaces at a relatively high temperature, the openings can be covered by a grid, in particular with mesh widths less than about 600 μm. Here, the grid may be arranged within or above the openings. However, the grid is preferably directly below the openings in the inflow base, as is known in principle from German patent application DE 197 50 424. In one practical variant, a metal gauze with an appropriate mesh width can be sintered, or attached in some other way, to the underside of an inflow base known per se. The metal gauze preferably consists of the same material as the inflow base, in particular of stainless steel. The fine-mesh grid prevents particles from falling through, particularly when the plant is shut down unexpectedly, but also especially in the case of particularly heavy particles with bulk densities around about 1000 g/l also during operation. The mesh width of said grid is preferably between about 200 and about 400 μm. In addition, it is advantageous if the inflow base used has a pressure loss of at most about 10 mbar and in particular at most about 6 mbar.

[0032] According to the invention, the aqueous consolidation and coating solution is applied in a fluidized-bed apparatus. Suitable consolidation and coating active ingredients are polymeric polycarboxylates, in particular polymerization products of acrylic acid, methacrylic acid or maleic acid, or copolymers of at least two of these, which may be used in completely or partially neutralized form, in particular in the form of the alkali metal salts. As an alternative to or in addition to polymeric polycarboxylate, phosphonic acid and/or alkali metal phosphonate can be used. In said alkali metal salts, sodium is the alkali metal preferred in each case. The solution is preferably adjusted to the lowest possible viscosity for good drop distribution upon atomization into the fluidized bed with simultaneous drying. The pH of the solution is adjusted to acidic values, in particular to values in the pH range from about 4 to about 4.4, if it is not in the acidic range from the outset, by adding system-compatible acids, in particular by adding sulfuric acid and/or citric acid. It is preferred, based on granules to be coated, to spray on an amount of the aqueous solution such that the coating constitutes about 1% by weight to about 25% by weight, in particular about 2% by weight to about 15% by weight.

[0033] Subsequently, the granules can then be discharged in a manner known in principle from the fluidized bed and, where necessary, be classified according to particle size, it being possible, as stated above, to return undesirably small particles (fine granules) and undesirably large particles (coarse granules), where desired, to a granulation process following a grinding step. In a particular embodiment of the method according to the invention, the classified acceptable granules can again be introduced into a fluidized-bed apparatus and consolidation and coating solution be sprayed onto them in order, if necessary, to further improve the product properties of the granules.

[0034] Granules coated by the method according to the invention are storage-stable, readily pourable and of adequate particle stability to allow them to be mixed in a customary manner with other particulate constituents of detergents or cleaners. Coated granules obtainable by the method according to the invention are used in, in particular particulate, detergents or cleaners, preferably in amounts such that these compositions have contents of from about 0.1% by weight to about 10% by weight, in particular from about 0.2% by weight to about 7% by weight, of bleach activator according to formula (I).

EXAMPLES

Example 1

[0035] Granules were prepared in a fluidized-bed apparatus (Glatt® AGT 400 with a diameter of 40 cm) with 400 m3/h of incoming air stream, an incoming air temperature of 95° C. and an outgoing air temperature of 55° C. from a homogeneous aqueous solution of trimethylammonium acetonitrile methosulfate and sodium cumenesulfonate (mass ratio 1:1, dry-substance fraction 30%) at a solution throughput of 3 kg/h over the course of 5 h; the granules were still very tacky. The tackiness was overcome by granulating again with a 20% strength aqueous solution of polymeric polycarboxylate (Sokalan® CP45, manufacturer BASF) under the same conditions with regard to incoming air stream, incoming air temperature and outgoing air temperature. The polymer fraction in the granules obtained in this way was 5% by weight. The size of the granules was in the range from 0.4 mm to 2.0 mm, the bulk density was 700 g/l. The granules were then sieved and the proportion with granule sizes of between 0.8 and 1.6 mm was mixed with the other detergent components of a detergent formulation. The finished detergent could be used without clumping.

Example 2

[0036] In a fluidized-bed apparatus with a diameter of 1.8 m (Glatt® AGT 1800), primary granules were prepared from a 40% strength aqueous solution of the cationic nitrile used in example 1, with powdering with Na cumenesulfonate powder. The amount of incoming air was 21 000 m3/h, the incoming air temperature was 145° C. The outgoing air temperature was adjusted to 65° C. by evaporating the water in this solution. After 1 h, the batch-operated fluidized-bed was so full that the granulation was stopped. The consolidation was carried out using the 20% strength polymer solution used in example 1 at an incoming air temperature of 110° C. The polymer content in the finished granules was 10% by weight. The resulting granules were sieved off between 0.8 and 1.6 mm. The bulk density was 730 g/l.

[0037] The finished granules were processed with customary particulate detergent components to give a particulate detergent.

Example 3

[0038] In a fluidized-bed apparatus with a diameter of 1.8 m (Glatt® AGT 1800), primary granules were prepared from a 40% strength aqueous solution of the cationic nitrile used in Example 1, with powdering with silica powder (Thixosil® 38A). The amount of incoming air was 20 000 m3/h, the incoming air temperature was 140° C. The outgoing air temperature was adjusted to 65° C. by evaporating the water in this solution. After 1 h, the batch-operated fluidized-bed was so full that the granulation was stopped. The consolidation was carried out using the 20% strength polymer solution used in example 1 at an incoming air temperature of 110° C. The polymer content in the finished granules was 7% by weight. The resulting granules were sieved off between 0.8 and 1.6 mm. The bulk density was 710 g/l.

Example 4

[0039] The granules obtained according to example 2 were introduced again into the fluidized-bed apparatus, where they were sprayed from the side with the 20% strength polymer solution already used above at an incoming air temperature of 130° C. and outgoing air of 65° C. to give a 20% by weight coating. Similarly, the granules obtained according to example 3 were again introduced into the fluidized-bed apparatus where they were sprayed from the side with the 20% strength polymer solution at an incoming air temperature of 130° C. and outgoing air of 65° C. to give a 10% by weight coating.

Example 5

[0040] In a fluidized-bed apparatus with a diameter of 15 cm (Glatt® AGT 1800), granules containing trimethylammonium acetonitrile methosulfate were sprayed with the polymer solution used in example 1 using two-component nozzles arranged at the bottom. The amount of incoming air was 100 m3/h, the incoming air temperature was 120° C. and the outgoing air temperature was 60° C. The two-component nozzles were operated with warm air at 75° C.; the air factor of the nozzles was 1.5 (kg of air/kg of solution). The proportion of the coating layer of the finished granules was 10% by weight. Under the microscope, a complete coating layer could be seen. The resulting granules consisted of particles with diameters in the range from 0.8 mm to 2.0 mm and had a bulk density of 750 g/l.

[0041] The disclosures of each patent, patent application, and publication cited or described in this document are hereby incorporated herein by reference, in their entireties.

[0042] Various modifications of the invention, in addition to those described herein, will be apparent to those skilled in the art from the foregoing description. Such modifications are also intended to fall within the scope of the appended claims.