EP1051473B1 - Bleaching activators in the form of storage-stable granules - Google Patents

Description

Bleach activators are important components in compact detergents, patch salts and machine dishwashing detergents. Already at 40 to 60 ° C they enable one of the Cook linen comparable bleaching result by using Hydrogen peroxide donor (usually perborates or percarbonates) with release react with an organic peroxyacid.

The achievable bleaching result is determined by the nature and reactivity of formed peroxycarboxylic acid, the structure of the bond to be perhydrolysed and the water solubility of the bleach activator. Since it is usually a reactive ester or an amide, it is necessary in many cases to use it for the intended use in granulated or coated form to to prevent hydrolysis in the presence of alkaline detergent ingredients and to guarantee a sufficient storage stability.

For the granulation of these substances are in the past numerous auxiliaries and methods have been described. EP-A-0 037 026 discloses a method for Production of an easily soluble active granulate with active contents between 90 and 98 wt .-% described. For this purpose, the powdery bleach activator with also powdered cellulose or starch homogeneously mixed and then sprayed with water or an aqueous solution of the cellulose ether, simultaneously granulated and then dried.

According to EP-A-0 070 474 similar granules can be prepared by spray-drying aqueous slurries containing the activator and the cellulose ether. Granules consisting of bleach activator, cellulose ethers and additions of an organic C ₃ -C ₄ -carboxylic or hydroxycarboxylic acid are described in WO 90/01535 and WO 92/13798. While according to WO 90/01535 the organic carboxylic acid is incorporated in the granules to accelerate its solubility, in WO 92/13798 the carboxylic acid is applied to the finished granules in an additional coating stage. The acidic protective coat is intended to prevent spotting of the bleach and contribute to the color of the fabric. In WO 94/03395 the use of acidic polymer compounds having a water solubility> 5 g / l (at 20 ° C) and molecular weights of 1000 to 250,000 is claimed for the same purpose.

Also described are granules of bleach activators, blends of Soaps and free fatty acids serve as granulating aids (GB-A-1 507 312).

An anhydrous manufacturing method is known from EP-A-0 075 818. This is the Bleach activator together with an organic binder, e.g. one Fatty alcohol ethoxylate, by compaction under pressure to particles with Diameters of 0.5 to 3 mm pressed.

For most of the above granulation is a prerequisite that the zu granulating bleach activator is a solid and has a high melting point having. This is necessary so that he does not use the binder or in the manufacture Abreacted and decomposed existing water. Thus, e.g. in DE-OS 2,048,331 preferred such activators having a melting point of preferably at least 100 ° C, in particular at least 150 ° C.

As binders so far predominantly organic compounds have been used. From this, however, problems may arise which make the use of the granules limit.

Are surface-active compounds used, such as soaps, fatty acids, anionic surfactants or fatty alcohol ethoxylates, so are those produced therewith Granules for use in machine dishwashing unsuitable because under Washing conditions foam problem occur. This is even when using usually low foaming highly ethoxylated fatty alcohols the case. To the Use in dishwasher detergents are therefore predominantly Activator granules used, the binder consists of cellulose ethers. The however, biodegradability of this product group is moderate.

Another problem are suitable granules for stain salts. Modern Formulations consist of mixtures of percarbonate and TAED granules. To an exothermic decomposition of these mixtures (percarbonate as fire-promoting substance in combination with organic material) in production and Storage are often inert materials, such as sodium carbonate, hydrogen carbonate or sulfate added. For this application would be inert binding or coating agents of great interest.

There is therefore still a need for suitable activator granules that are made Ecological point of view unproblematic, universally applicable and cost-effective are to produce.

Inorganic materials as carriers for bleach activators are known per se. So In DE-OS 2,733,849 the adsorption of liquid activators, such as Diacetylmethylamine, diacetylbutylamine or acetalcaprolactam, to inorganic Adsorbents, such as diatomaceous earth, magnesium aluminum silicates, sodium or Calcium aluminum silicates, activated silica or alumina, proposed. However, granules are not described there.

Furthermore, according to GB-A 2 249 104 particles can be prepared in which a solid bleach activator in finely divided form on inorganic support material is deposited. For this purpose, the activator and support material are first intimately mixed and an organic solvent (ethanol or toluene) added, wherein the activator goes into solution. By subsequent distillation of the solvent is the Activator deposited in finely distributed form on the support. The preferred Grain size distribution of the particles according to the invention is between 60 and 250 μm.

In addition, from EP-A-0 240 057 bleach activator granules are known which Mixing an activator with inorganic and organic salts, film-forming polymers and small amounts of smectites or aluminum silicates and subsequent granulation in the presence of water. To Granulation is a costly drying step necessary to To obtain storage-stable granules.

In the published patent application DE-OS 44 39 039 is an anhydrous and solvent-free Granulating process described, wherein as a binder bentonites, in particular alkaline activated bentonites are used.

Surprisingly, it has now been found that the storage stability improved and the active content of Aktivatorgranulaten can be increased if Binders acid modified phyllosilicates are used.

The invention relates to a storage-stable bleach activator granules, which in the essentially from a bleach activator and an acid-modified phyllosilicate and which is obtainable by mixing the dry bleach activator with the dry, acid-modified phyllosilicate, pressing this mixture to larger agglomerates and crushing these agglomerates to the desired Grain size.

As acid-modified phyllosilicates, mineral-acid-treated phyllosilicates, preferably bentonites, in particular smectitic clays from the group of alkali or alkaline earth montmorillonites, saponites or hectorites, are suitable. Particularly preferred are the products of this type which are commercially available under the names ®Tonsil EX 519, Tonsil Optimum 210 FF, Tonsil Standard 310 FF and 314 FF and ®Opazil SO from Süd-Chemie, Munich (DE). Depending on requirements the aforementioned binding materials are used as individual substances or as mixtures. As a result of the acidic modification, the alkali and / or alkaline-earth ions are removed between the layered laminates of the sheet silicates and replaced by hydrogen ions. After complete exchange, with further addition of acid in the edge region of the layer packages, partial removal of the Al and Mg ions from the octahedral layer takes place. What remains is voluminous silica, which is connected via SiO ₄ tetrahedra or with the unimpacted bentonite. This leads to a loosening of the crystal structure and to a certain disorientation of the layer packages. The particles of the acid-modified sheet silicates are finer and the specific surface area is greatly increased. These products are, so to speak, an intramolecular combination of amorphous silicic acid and phyllosilicate.

According to the invention, as bleach activators, those having melting points above 60 ° C are used. Examples of these are tetraacetylethylenediamine (TAED), tetraacetylglucoluril (TAGU), diacetyldioxohexahydrotriazine (DADHT), Acyloxibenzenesulfonates, such as nonanoyloxibenzenesulfonate sodium (NOBS) or Benzoyloxibenzenesulfonate (BOBS) and acylated sugars, such as pentaacetylglucose (PAG) or compounds as described in EP-A-0 325 100, EP-A-0 492 000 and WO 91/10719 are described.

Other suitable bleach activators are known in the art activated carboxylic esters, carboxylic anhydrides, lactones, acylals, Carboxylic acid amides, acyl lactams, acylated ureas and oxamides, next to it but in particular also nitriles, which in addition to the nitrile group also a quaternized May contain ammonium group. Mixtures of different bleach activators can also be used.

In addition, the granules according to the invention may contain further additives such as anionic and nonionic surfactants containing the Consistency and hardness of the granules of the invention, as well as the homogeneous Favorably influence the distribution of bleach activators.

Preferred anionic surfactants are alkali metal salts. Ammonium salts, amine salts and hydroxylalkylamine salts of the following compounds:
Alkyl sulfates, alkyl ether sulfates, alkylamide sulfates and ether sulfates, alkylaryl polyether sulfates, monoglyceride sulfates, alkylsulfonates, alkylamide sulfonates, alkylarylsulfonates, α-olefin sulfonates, alkyl sulfosuccinates, alkyl ether, Alkylamidsulfosuccinamate, alkyl sulfoacetates, Alkylpolyglycerin carboxylates, alkyl phosphates, alkyl ether phosphates, alkyl sarcosinates, Alkylpolypeptidate, Alkylamidopolypeptidate, Alkylethionate, alkyl taurates. The alkyl radical of all these compounds contains 8 to 31 C atoms, preferably 8 to 22 C atoms in a linear chain.

Further suitable anionic surfactants are fatty acids, such as oleic acid, ricinoleic acid, palmitic acid, stearic acid and salts thereof, coconut oil salt or hydrogenated coconut oil acid salts, carboxylic acids of polyglycoethers of the general formula A - (OCH ₂ - CH ₂ ) _n - OCH ₂ - CO ₂ H wherein AC ₁₂ -C ₁₈ alkyl and n is an integer between 5 and 15, are also suitable as anionic additives for the granules of the invention in question.

As nonionic surfactants are polyethoxylated, polypropoxylated or polyglycerolated ethers of fatty alcohols, polyethoxylated, polypropoxylated and polyglycerinated fatty acid esters, polyethoxylated esters of fatty acids and of Sorbitol, polyethoxylated or polyglycerinated fatty amines are preferred.

Other additives include substances that are in the suds with those from the activator liberated peroxycarboxylic acid to form reactive intermediates, such as Dioxiranes or oxaziridines, and thus reactivity can increase. Corresponding compounds are ketones and sulfonimines according to US-A-3 822 114 and EP-A-0 446 982. Additions are possible. which affect the bleaching ability, such as complexing agents, polycarboxylates and Iron- or manganese-containing metal complexes, as in EP-A-0 458 397 and EP-A-0 458 398.

The ratio of bleach activator to binder is usually 50:50 to 98: 2, preferably 70:30 to 96: 4, based on the total weight of the granules. The quantities of the additives depend in particular on their type generally sufficient amounts of 0 to 20 wt .-%, in particular amounts of 1 to 10 wt .-%, based on the total weight of the granules. metal complexes on the other hand, concentrations in the ppm range are added.

For the preparation of the granules is first in a mixing unit (e.g. Pflugscharmischer) the mixture of bleach activator and binder intimately mixed (step a). In a second step, the mixture becomes larger Particles pressed (step b). Suitable for this are u.a. Roller compactors. The Pressings are then subjected to comminution (grinding) and on crushed the desired grain size (step c). Suitable for this purpose Sprocket rollers and / or Passiersiebe.

Fines and coarse material are sieved and returned to the process. While the coarse fraction is fed directly to a further comminution, the fine fraction is added to the compacting stage. The grain size of the product is generally in the range of 100 to 2000 microns, preferably 300 to 1800 microns. The bulk density of the granules according to the invention is above 500 kg / m ³ , preferably above 600 kg / m ³ .

The granules obtained in this way are directly for use in washing and Detergents suitable. This includes bleach and disinfectants. In a particularly preferred form of use, however, they can with a Coating shell be provided.

For this purpose, the granules according to the invention in an additional step d) with wrapped in a film-forming substance, whereby the product properties considerably can be affected.

Suitable coating agents are all film-forming substances, such as waxes, Silicones, fatty acids, soaps, anionic surfactants, nonionic surfactants, cationic Surfactants as well as anionic and cationic polymers, e.g. Polyacrylic acid.

Preference is given to coating substances having a melting point of 30-100 ° C. used.

By using these coating materials, i.a. the dissolution behavior be delayed to interactions between the bleach activator and the Prevent enzyme system at the beginning of the washing process. In addition, can be in this way reduce the dust content, increase the abrasion resistance and the Improve storage stability.

If the granules of the invention in machine dishwashing detergents use For this purpose, especially waxes with melting points of 40 to 50 ° C are suitable.

Acid coating agents increase the storage stability of the granules in percarbonate-containing, highly alkaline formulations and suppress Color damage due to spotting. Additions of a dye are also possible.

The application of the coating materials is usually carried out by spraying the melted or dissolved in a solvent coating materials. According to the Invention, the coating material in amounts of 0 to 20, preferably from 1 to 10 wt .-%, based on the total weight, on the inventive Granulated core are applied.

The products according to the invention are distinguished by good lab stability powdered washing, cleaning and disinfectant formulations.

They are ideal for use in heavy-duty detergents, stain salts, Machine dishwashing detergents, powdered all-purpose cleaners and denture cleaners.

In these formulations, the granules of the invention are usually in Used in combination with a hydrogen peroxide source. examples for this are Perborate monohydrate, perborate tetrahydrate, percarbonates as well Hydrogen peroxide adducts on urea or amine oxides.

In addition, the formulation according to the prior art further Have detergent ingredients, such as organic and inorganic builders and Co-builder, surfactants; Enzymes, brighteners and perfume.

The following examples are intended to explain the invention in more detail without them limit.

Manufacturing and application examples Example 1: Preparation

In a 50 liter Lödige mixer, 10 kg of a mixture of 92% by weight TAED and 8 wt .-% of an acid-modified bentonite (®Tonsil EX 519 Fa. Süd-Chemie AG, Munich (DE)) at a speed of 70 rpm over a period of 10 mixed intensively. This homogeneous mixture is then applied to a Roller compactor Pharmapaktor (Bepex (DE)) with a pressing force of 50 to 60 kN pressed into slugs, then in a two-stage grinding, pre-grinding with toothed disc rollers (company Alexanderwerk (DE)) and crushing in one Passiersieb (Frewitt (DE)) crushed at a mesh size of 2000 microns become. This gives 5.3 kg of granules with a particle size distribution of 200 to 1600 microns (Yield: 53%), and 2.8 kg fines <200 microns (28%), by renewed Compaction can be recycled and 1.9 kg coarse fraction> 1600 microns (19%), which can be worked up by re-grinding.

Example 2: Activation rate

Granulat 1: erfindungsgemäßes Granulat gemäß Beispiel 1

Granulat 2: Vergleichsbeispiel, Granulat gemäß DE-OS 44 39 039 (Beispiel 1 )

Zeit [min] freigesetzte Peressigsäure in % aus Granulat 1 Granulat 2 1 20 29 3 42 68 5 65 84 7 77 93 9 85 100 11 91 13 95 15 98 17 100 8 g of standard detergent WMP without bleach system (Laundry Research Krefeld (DE)) and 1.5 g of sodium perborate monohydrate are dissolved in 1 l of distilled water at 20 ° C. in a 2 l beaker, and then 0.5 g of the activator are added. Depending on the time after Aktivatorzugabe the content of peracetic acid formed is determined by iodometric titration. As activators, the following products are used in this study:

Granules 1: Granules according to the invention according to Example 1

Granules 2: Comparative Example, Granules According to DE-OS 44 39 039 (Example 1)

Time [min] released peracetic acid in% Granules 1 Granules 2 1 20 29 3 42 68 5 65 84 7 77 93 9 85 100 11 91 13 95 15 98 17 100

The granules 1 according to the invention have compared to the comparative example Granules 2 at a temperature of 20 ° C a delayed peracetic acid formation on a better stabilization of the activator TAED in granules 1 is due.

Example 3: Storage stability

To determine the storage stability, 8.0 g of standard detergent WMP without bleach system (WfK (DE)) are homogeneously mixed with 1.5 g of sodium perborate monohydrate and 0.5 g of activator and the mixture is then placed in cartons at 38 ° C. and 80% relative humidity in a climatic chamber stored (quick test). At certain intervals, the remaining activator content is determined by iodometric titration.
The activators used are granules 1 and granules 2 according to example 2. days Residual content activator (%) Granules 1 Granules 2 2 98 97 7 81 62 10 65 37 14 51 27

The example shows that the granules 1 according to the invention have the same active content (92%) has a significantly better storage stability compared to granules 2 (Comparative example).

Example 4: bleaching activity

The bleaching activity of active granules is determined by washing tests in a Linitest apparatus (Hereaus, Hanau (DE)). in a beaker with 200 ml of water (15 ° dH), add 1.0 g of standard detergent (WMP) without bleach system (WfK (DE)), 150 mg of sodium perborate monohydrate and 50 mg of activator, add the test stain and then in the Linitest instrument 10 min while heating from 20 ° C to 40 ° C and 20 min at 40 ° C washed. Tissue on cotton (WfK (DE)) is used as the test soil for testing the bleaching activity. The whiteness of the fabrics is determined by means of an Elrepho colorimeter 2000 (Datacolor (DE)).
The activators used are granules 1 and granules 2 according to example 2. test soil Remission difference (%) Granules 1 Granules 2 Tea on cotton 26.8 27.2

The example shows that the granules 1 of the invention with improved Storage stability has a bleaching activity comparable to the prior art.

Claims (8)

1. Storage-stable bleach activator granules consisting essentially of a bleach activator and an acid-modified phyllosilicate, obtainable by mixing a dry bleach activator with a dry, acid-modified phyllosilicate, compressing this mixture to give relatively large agglomerates and comminuting these agglomerates to the desired particle size.
2. Storage-stable bleach activator granules as claimed in claim 1, wherein the acid-modified phyllosilicates used are natural and/or artificial bentonites.
3. Storage-stable bleach activator granules as claimed in claim 1, wherein the bleach activator used comprises N-acylated amines, amides, lactams, lactones, oxamides, nitriles, which, in addition to the nitrile group, may also contain a quatemized ammonium group, activated carboxylic acid esters and/or carboxylic anhydrides.
4. Storage-stable bleach activator granules as claimed in claim 1, wherein the weight ratio of bleach activator to acid-modified phyllosilicate is from 50:50 to 98:2, preferably from 70:30 to 96:4.
5. Storage-stable bleach activator granules as claimed in claim 1, wherein the granules comprise from 0 to 20% by weight, based on the total weight, of an additive.
6. Storage-stable bleach activator granules as claimed in claim 1, wherein the granules have a particle size in the range from 100 to 2000 µm, preferably from 300 to 1800 µm.
7. Storage-stable bleach activator granules as claimed in claims 1 to 6, wherein the granules are additionally coated with a coating layer.
8. The use of the storage-stable bleach activator granules as claimed in one of claims 1 to 7 in detergents and cleaning compositions.