EP1017776B1 - Bleaching activators in the form of granules - Google Patents

Description

Bleach activators are important components in detergents, stain salts and Dishwashing detergents. They already enable a bleaching effect Temperatures below 60 ° C by using a source of hydrogen peroxide - mostly Perborates or percarbonates - with the release of an organic peroxy acid react.

A large number of reactive organic are suitable as bleach activators Compounds with an O-acyl or N-acyl group. Representative examples like N, N, N ', N'-tetraacetylethylenediamine (TAED), glucose pentaacetate (GPA), Xylose tetraacetate (TAX), sodium 4-benzoyloxybenzenesulfonate (SBOBS), Sodium trimethylhexanoyloxybenzenesulfonate (STHOBS), tetraacetylglucoluril (TAGU), tetraacetylcyanoic acid (TACA), di-N-acetyldimethylglyoxin (ADMG) and 1-phenyl-3-acetylhydantoin (PAH) are described in GB-A-836 988, GB-A-907 356, EP-A-0 098 129 and EP-A-0 120 591.

Meanwhile, cationic bleach activators have a quaternary Contain ammonium group, gained importance because they are highly effective Are bleach activators. Such cationic bleach activators are for example in GB-A-1 382 594, US-A-4 751 015, EP-A-0 284 292 and EP-A-0 331 229 described.

wobei R¹, R² und R³ Alkyl-, Alkenyl- oder Arylgruppen bedeuten, bilden dabei eine besondere Klasse kationischer Bleichaktivatoren. Verbindungen dieser Art und deren Verwendung als Bleichaktivatoren in Bleichmitteln sind beschrieben in EP-A-303 520, EP-A-464 880, EP-A-458 396 und US-4 883 917. Bei allen dort beschriebenen Verbindungen ist das Stickstoffatom der Ammoniumgruppe durch Alkyl-, Alkenyl- oder Arylgruppen substituiert. Eine weitere Klasse von Ammoniumnitrilen ist in der Deutschen Patentanmeldung 19 605 526 beschrieben.Ammonium nitriles of the formula

where R ¹ , R ² and R ^{3 are} alkyl, alkenyl or aryl groups, form a special class of cationic bleach activators. Compounds of this type and their use as bleach activators in bleaching agents are described in EP-A-303 520, EP-A-464 880, EP-A-458 396 and US-4,883,917. In all the compounds described there, the nitrogen atom is the ammonium group substituted by alkyl, alkenyl or aryl groups. Another class of ammonium nitriles is described in German patent application 19 605 526.

Bleach activators are usually used in granular form in detergents used to ensure sufficient storage stability and to Release bleach activating effects only in the wash cycle.

There have been numerous granulations of bleach activators in the past Auxiliaries and processes have been described. EP-A-0 037 026 describes a Process for the production of easily soluble activator granules Active contents between 90 to 98 wt .-% described. For this, the powdered Bleach activator with homogeneous powdered cellulose or starch ethers mixed and then with water or an aqueous solution of Cellulose ether sprayed, granulated at the same time and then dried.

According to EP-A-0 070 474, similar granules can be produced by spray-drying aqueous slurries containing the activator and the cellulose ether. Granules consisting of bleach activator, cellulose ethers and additives of an organic C ₃ -C ₆ carbon or hydroxy carboxylic acid are described in WO 90/01 535 and WO 92/13 798. While in WO 90/01 535 the organic carboxylic acid is incorporated into the granulate core to accelerate its solubility, in WO 92/13 798 the carboxylic acid is applied to the finished granulate in an additional coating step. The acidic protective coat is intended to prevent spotting of the bleaching agent and to protect the color of the fabric. WO 94/03 395 claims for the same purpose the use of acidic polymer compounds with a water solubility> 5 g / l (at 20 ° C.) and molar masses of 1000 to 250,000. Also known (GB-A 1 507 312) are granules of bleach activators in which mixtures of soaps and free fatty acids are used as granulation aids.

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

For most of the granulation processes mentioned, it is a prerequisite that the granulating bleach activator is a solid and has a high melting point having. This is necessary so that it is not made with the binder or existing water is reacted and decomposed. For example, in DE-OS 2 048 331 preferred such activators that have a melting point of preferably have at least 100 ° C, in particular at least 150 ° C.

So far, mostly organic compounds have been used as binders. However, this can result in problems with 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 with them Granules unsuitable for use in machine dishwashing detergents because they are under Washing conditions foam problems occur, even when using normally low foaming highly ethoxylated fatty alcohols. To the Use in machine dishwashing detergents is therefore predominant Activator granules are used, the binder of which consists of cellulose ethers. The however, the biodegradability of this product group is moderate.

Suitable granules for use in stain salts are another problem. Modern formulations consist of mixtures of percarbonate and Bleach activator granules. To exothermic decomposition of these mixtures Preventing production and storage are often inert materials such as Sodium carbonate, hydrogen carbonate or sulfate added. For this Inert binding or coating agents would be of great interest.

Inorganic materials as carriers for bleach activators are known per se. So is in DE-OS 2 733 849 the adsorption of liquid activators, such as Diacetylmethylamine, diacetylbutylamine or acetylcaprolactam, to inorganic Adsorbents such as diatomaceous earth, magnesium aluminum, sodium or Calcium aluminum silicates, activated silica or aluminum oxide, proposed.

According to GB-A-2 249 104, particles can also be produced in which a bleach activator which is solid per se is deposited in finely divided form on an inorganic carrier material. For this purpose, the activator and carrier material are first mixed intimately and an organic solvent (ethanol or toluene) is added,
whereby the activator goes into solution. Subsequent distillation of the solvent causes the activator to be deposited on the carrier in finely divided form. The preferred particle size distribution of the particles according to the invention is between 60 and 250 μm.

In addition, EP-A-0 240 057 bleach activator granules are known which pass through Mixing an activator with inorganic or organic salts, film-forming polymers and small amounts of smectites or Aluminum silicates and subsequent granulation in the presence of water getting produced. Once granulation has taken place, it is costly Drying level necessary to obtain granules that are stable in storage.

Bleach activator granules obtained by mixing and pressing dry Bleach activator and smectites (bentonite) obtained in the absence of water are known from DE-A 44 39 039. As a bleach activator there essentially only uses TAED. The influence of TAED on washing performance is however, essentially regardless of whether the TAED is in granular form is present or as a powder.

Surprisingly, it has now been found that the bleach activators of the type the ammonium nitrile very large differences in their washing performance exist between the powder form and the granulate form.

The invention thus relates to bleach activator granules consisting of essentially from an ammonium nitrile and a layered silicate.

These granules are obtained by mixing the two components, Pressing and crushing the agglomerates thus obtained to the desired one Grain size.

worin R¹ und R² C₁-C₄ Alkyl, vorzugsweise Methyl und X ein Anion, beispielsweise Chlorid oder Methosulfat, bedeuten.All ammonium nitriles which have a melting point above 60 ° C. in granular form can be used for the granules. In particular, the ammonium nitriles described in the above-mentioned literature come into question, in particular the compounds described in DE 19 605 526. Compounds of the formula are very particularly preferred

wherein R ¹ and R ^{2 are} C ₁ -C ₄ alkyl, preferably methyl and X is an anion, for example chloride or methosulfate.

Granules can contain one or more of these ammonium nitriles or additionally also bleach activators of other structures, for example N, N, N ', N'-tetraacetylethylenediamine (TAED), glucose pentaacetate (GPA), xylose tetraacetate (TAX), sodium 4-benzoyloxybenzenesulfonate (SBOBS), Sodium trimethylhexanoyloxybenzenesulfonate (STHOBS), tetraacetylglucoluril (TAGU), tetraacetylcyanoic acid (TACA), di-N-acetyldimethylglyoxin (ADMG) and 1-phenyl-3-acetylhydantoin (PAH).

Layered silicates, in particular, serve as binders for the formation of the granules Smectites such as montmorillonite, saponite or hectorite ion exchange capacities of preferably 50 to 100 meq / 100 g, besides Illite, Attapulgite and Kaolinite. Bentonites such as those under the Designation ®Laundrosil DGA and Laundrosil EX 0242 from Süd-Chemie, Munich (DE) are on the market. These layered silicates can also be acidic modified form, as used in the commercial products ®Tonsil EX 519, Tonsil Optimum 210 FF, Tonsil Standard 310 FF and 314 FF, and ®Opazil SO from Süd-Chemie, Munich (DE).

In addition, the granules according to the invention can also be others Contain aids, such as those that adjust the pH during the Storage and application affect. These include organic carboxylic acids or their salts, such as citric acid in anhydrous or hydrated form, Glycolic acid, succinic acid, maleic acid or lactic acid. Are also next to it Additions possible which influence the bleaching capacity, 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 weight ratio of ammonium nitrile to inorganic binder is usually 50:50 to 98: 2, preferably 70:30 to 96: 4. The amount any additives depend in particular on their type acidifying additives and organic catalysts to increase the performance of the Peracid in amounts of 0 to 20% by weight, in particular in amounts of 1 to 10% by weight, based on the total weight, was added, but metal complexes in concentrations in the ppm range.

To manufacture the granules, a mixing unit (e.g. Ploughshare mixer) the mixture of ammonium nitrile and binder intimately mixed. In a second step, the mixture becomes larger particles pressed. Suitable for this include Roller compactors. The compacts will then subjected to comminution (grinding) and to the desired Grain size crushed. Toothed pulley rollers and / or are suitable for this purpose Passiersrebe.

Fine fraction and coarse material are screened off and returned to the process. While the coarse fraction is directly re-crushed, the fine fraction is added to the compacting stage. The grain size of the product is generally in the range from 100 to 2000 μm, preferably 300 to 1800 μm. The bulk density of the granules according to the invention is thus above 500 kg / m ³ , preferably above 600 kg / m ³ .

The granules obtained in this way can be used directly in washing and Suitable detergents. They can be used in a special way however, be provided with a coating envelope.

For this purpose, the granules according to the invention are processed in an additional step with a film-forming substance envelops, making the product properties significant can be influenced.

All film-forming substances, such as waxes, are suitable as coating material. Silicones, fatty acids, soaps, anionic surfactants, nonionic surfactants, cationic Surfactants, as well as anionic and cationic polymers, e.g. Polyacrylic. By The use of these coating materials can include the dissolution behavior is delayed interactions between the bleach activator and to prevent the enzyme system at the beginning of the washing process. Should that intended granules are used in dishwasher detergents, waxes with melting points of 40 to 50 ° C are particularly suitable for this.

Acidic coating materials increase the storage stability of the granules in highly alkaline formulations containing percarbonates and suppress Color damage due to spotting. Additions of a dye are also possible.

The coating materials are usually applied by spraying the melted or dissolved in a solvent coating materials. According to the Invention can the coating material in amounts of 0 to 20, preferably from 1 to 10 wt .-%, based on the total weight of the invention Granules are applied.

The products according to the invention are characterized by good storage stability powder detergent, cleaning and disinfectant formulations. she are ideal for use in heavy-duty detergents, stain salts, Dishwasher detergents, powdered all-purpose cleaners and denture cleaners.

The granules according to the invention are used in combination in these formulations used with a hydrogen peroxide source. Examples include perborate monohydrate, Perborate tetrahydrate, percarbonates and hydrogen peroid adducts of urea or amine oxides. In addition, the wording can reflect the status of Technology accordingly have other components, such as organic or inorganic builders and co-builders, surfactants, enzymes, optical brighteners and Perfume.

Manufacturing and application examples Example 1 (Production)

10 kg of a mixture of 92% by weight ammonium nitrile (trimethylammonium acetonitrile toluenesulfonate = granulate 1 or N-cyanomethyl-N-methylpiperazinium toluenesulfonate = granulate 2) and 8% by weight bentonite (®Laundrosil DGA ) intensively mixed at a speed of 70 rpm over a period of 10 min.
This homogeneous mixture is then pressed on a roller compactor Pharmapaktor (Fa. Bepex (DE)) with a compressive force of 50 to 60 kN to flakes, which are then subjected to a two-stage grinding, pre-grinding with toothed disk rollers (Fa. Alexanderwerk (DE)) and comminution in a passing sieve (from Frewitt (DE)) with a mesh size of 2000 µm.
This gives 5.3 kg of granules with a particle size distribution of 200 to 1600 µm (yield: 53%), as well as 2.8 kg of fine particles <200 µm (28%), which can be recycled by further compacting, and 1.9 kg of coarse particles > 1600 µm (19%), which can be worked up by renewed grinding.

Example 2 (storage stability)

To determine the storage stability, 10 g of standard detergent WMP without bleaching system (WfK (DE)) were mixed homogeneously with 1.5 g of sodium perborate monohydrate and 0.5 g of activator or activator granules containing 0.5 g of activator, and the mixture was then packed in folding boxes at 38 ° C and 80% relative humidity stored in a climate cabinet (quick test). The remaining activator content was determined at certain intervals by iodometric titration.
Trimethylammonium acetonitrile toluenesulfonate (1) and N-cyanomethyl-N-methylpiperazinium toluenesulfonate (2) were used as activators, each as a powder and as activator granules, granules 1 and granules 2 according to Example 1. days Residual activator content (%) Ammonium nitrile 1 Ammonium nitrile 2 Granules 1 Granules 2 2 98 92 98 98 7 72 69 92 93 10 41 37 87 85 14 20 14 82 80

This example shows that the ammonium nitriles in powdered form quickly Lose active content. in granular form, however, the activators are stable on storage.

Example 3 (bleaching activity)

The bleaching activity of the granules according to the invention was tested under practical conditions in a multi-component washing machine Öko-Lavamat 6753 (AEG, Nuremberg) on bleaching test fabrics in the presence of pure test laundry. In accordance with the dosing instructions for water hardness range 3, 70 g of reference detergent (WMP) was added to the washing machine's provided detergent dispenser. As a bleaching component, 8.0 g of percarbonate were added to the induction chamber provided for this purpose
2.93 g bleach activator granules 1 (92%) according to Example 1,
3.37 g bleach activator granules 2 (92%) according to Example 1,
2.52 g of bleach activator granules 3 (92%) based on TAED according to Example 1 from DE-A 44 39 039.

For comparison, the ammonium nitriles trimethylammonium acetonitrile toluenesulfonate (1) and N-cyanomethyl-N-methylpiperazinium toluenesulfonate (2) and TAED (3) were tested in non-granulated form:
2.7 g bleach activator powder 1
3.1 g bleach activator powder 2
2.3 g bleach activator TAED powder

2 kg of terry cloth were used as fiber, 10 bleachable stains as test soils (tea, red wine, curry, grass from the Krefeld laundry research). The laundry was washed in the main wash at 40 ° C. The evaluation is carried out by determining the degree of whiteness after washing by adding the reflectance differences, measured with ELREPHO 2000 (Datacolor). Reflectance differences Granules 1 Granules 2 Granules 3 Powder 1 Powder 2 Powder 3 310 285 194 55 63 200 T = 40 ° C; Tea, red wine, curry, grass

This example shows that in the case of ammonium nitriles, a very substantial increase in bleaching performance can be achieved. This is Surprising because the TAED activator, which is widely used in practice, Granulation has no significant influence on the bleaching performance.

Claims (8)

1. Bleach activator granules consisting of one or more ammonium nitriles and phyllosilicate, obtained by mixing the two components, compressing them and comminuting the resulting agglomerates to the desired particle size.
2. The bleach activator granules as claimed in claim 1, which, in addition to the ammonium nitriles, comprise bleach activators having another structure.
3. The bleach activator granules as claimed in claim 1, wherein the ammonium nitrile present is a compound of the formula

   

   in which R¹ and R² are C₁-C₄-alkyl and X is an anion.
4. The bleach activator granules as claimed in claim 1, wherein the phyllosilicate present comprises natural or acid-modified bentonites.
5. The bleach activator granules as claimed in claim 1, which essentially consist of ammonium nitrile and phyllosilicate in the weight ratio from 50:50 to 98:2.
6. The bleach activator granules as claimed in claim 1, which have a particle size of from 100 to 2000 µm.
7. The bleach activator granules as claimed in claim 1, which comprise up to 20% by weight, based on the weight of the granules, of one or more additives in the form of inorganic acids, organic acids, complexing agents, ketones and metal complexes.
8. A detergent, cleaning composition, bleach or disinfectant comprising bleach activator granules as in one or more of claims 1 to 7.