EP0881279B2 - Granules containing cationic surfactant - Google Patents

Abstract

A solid granulate is claimed which contains (A) 50-40 wt.% cationic, textile-softening agent of formula (I), (II) and/or (III), where R<1> = 1-6C alkyl, alkenyl or hydroxyalkyl; R<2> = 8-28C alkyl or alkenyl; R<3> = as for R<1> or -(CH2)n-T-R<2>; R<4> = as for R<1> or R<2>, or -(CH2)n-T-R<2>; T = -CH2-, -O-CO- or -CO-O-; and n = 0-5; (B) 50-90 wt.% solid carrier comprising an alkali metal-sulphate, -carbonate, -silicate, -citrate or -aluminium silicate or citric acid; and (C) 0-5 wt.% granulating auxiliaries. Also claimed is production of the granulate by low energy impacting of a solid carrier with a cationic surfactant in a mixer, followed by high energy granulation in the presence of water or an aqueous solution of a granulating auxiliary.

Description

The invention is in the field of production of cationic surfactant-containing granules, as used for example in special detergents and cleaners, but also in fabric softeners.

Cationic surfactants are used in special detergents and cleaners, but especially in laundry aftertreatment agents, such as fabric softeners, in order to give the textiles treated with the corresponding compositions a soft, fluffy feel and pleasant wear properties. In addition, the cationic surfactant applied to the fabrics facilitates ironing and results in an antistatic effect, which in turn improves the wearing properties.

Usually, the cationic surfactants are incorporated in the form of dispersions in the mostly liquid to pasty agent. Solid preparation forms which contain only cationic surfactant and no other surfactants as the active substance are comparatively rare.

Nevertheless, there has been no lack of attempts to produce cationic surfactants in the form of solid storage-stable preparation forms, so as to optionally also solid detergent compositions or fabric softeners can produce.

Thus, German Offenlegungsschrift DE 32 43 983 (Degussa AG) describes a free-flowing plasticizer concentrate which consists of one or more cationic surfactants which, if appropriate in admixture with one or more solubilizers, are applied to synthetic silica. The preparation of the agent is carried out by mixing a melt or a solution of the cationic surfactant in isopropanol with the precipitated and spray-dried silica.

Powdered laundry softeners which contain cationic surface-active substances adsorbed on highly absorbent silicic acid are also described in German Offenlegungsschrift DE 34 02 437 (REWO Chemische Werke GmbH). Here, the cationic surfactants are applied as a melt or solution in isopropanol to the silicic acid introduced in the mixer and then granulated under shear.

Special solid cationic surfactant preparation forms which are obtained by alkylation of triethanolamine esters in the presence of suitable dispersants (in particular fatty alcohols) are described in German Patent DE 43 08 794 (Henkel KGaA). The products obtained in this way have a flake-like structure and low bulk densities.

The first two methods have the disadvantage that the cationic surfactant is applied in the form of its isopropanolic solution or as a melt to an insoluble carrier. In the first case, extensive occupational safety and security measures are required and, in addition, the isopropanol must later be removed by evaporation, since alcohols adversely alter the powder properties of detergent compositions. In the second case, an energy expenditure for melting the cationic surfactant is required.
In addition, the use of silica in high amounts leads, when used in detergents and fabric softeners, to formation of residues in the treated textiles. All the processes of the prior art have in common the disadvantage that they provide products which are only sparingly or not residue-free soluble. The latter method also provides products of undesirable low bulk density.

The object of the invention was therefore to provide a process for the preparation of cationic surfactant-containing granules which overcomes said process and product disadvantages.

• a) 5 bis 40 Gew.-% eines oder mehrerer quaternierter Triethanolaminester mit textilweichmachender Wirküng der Formel I,
  
  worin jede Gruppe R¹ unabhängig voneinander ausgewählt ist aus C_1-6-Alkyl-, -Alkenyl- oder -Hydroxyalkylgruppen; jede Gruppe R² unabhängig voneinander ausgewählt ist aus C_8-28-Alkyl- oder -Alkenylgruppen; T = -O-CO- und n eine ganze Zahl von 0 bis 5 ist,
• b) 50 bis 90 Gew.-% eines festen Trägers aus der Gruppe der Alkalimetallsulfate, -carbonate, -silikate, -citrate und -aluminiumsilikate und Citronensäure sowie natürliche Poly saccharide und deren Derivate
• c) 0,1 bis 5 Gew.-% eines oder mehrerer Granulierhilfsmittel, aüsgewahlt aüs der Grüppe der Carboxymethyl cellülose, Wasserglässer oder Citronensäure

jeweils bezogen auf das Gewicht des Granulats, enthält.The invention relates to a solid, cationic surfactant-containing granules

• a) from 5 to 40% by weight of one or more quaternized triethanolamine esters with textile-softening action of the formula I,
  
  wherein each R ^{1 group is} independently selected from C _1-6 alkyl, alkenyl or hydroxyalkyl groups; each R ^{2 group is} independently selected from C _8-28 alkyl or alkenyl groups; T = -O-CO- and n is an integer from 0 to 5,
• b) 50 to 90 wt .-% of a solid support from the group of alkali metal sulfates, carbonates, silicates, citrates and aluminum silicates and citric acid and natural poly saccharides and derivatives thereof
• c) 0.1 to 5 wt .-% of one or more granulation, aüsgewahlt aüs the group of carboxymethyl celluless, waterglasses or citric acid

in each case based on the weight of the granules.

The cationic surfactant can be added directly to the mixer in its delivery form, or can be sprayed onto the solid carrier in the form of a liquid to pasty cationic surfactant formulation. Such cationic surfactant formulations can be prepared, for example, by mixing commercial cationic surfactants with excipients such as nonionic surfactants, polyethylene glycols or polyols. Also, lower alcohols such as ethanol and isopropanol can be used, and the amount of such lower alcohols in the liquid cationic surfactant preparation should be below 10% by weight for the reasons mentioned above. Here, solid cationic surfactants are simply added and act on the carrier in the course of granulation; Cationic surfactant forms of other states of aggregation are added, poured or atomized depending on the viscosity. As solid carriers to which the cationic surfactant is applied, carriers are selected from the group of alkali metal sulfates, carbonates, silicates, citrates, aluminum silicates and citric acid. Particularly preferred are water-soluble excipients and, among these, especially the sodium sulfate.

In addition, natural polysaccharides such as cellulose and starch and their derivatives are preferred support materials. These include in particular cellulose and starch itself, but also cellulose and starch derivatives obtainable by polymer-analogous reactions of cellulose or starch. Such chemically modified celluloses or starches include, for example, products of esterifications or etherifications in which hydroxy hydrogen atoms have been substituted. But also celluloses or starches, in which the hydroxy groups against functional Groups that are not bound by an oxygen atom have been replaced, can be used as a carrier material. The group of these derivatives includes, for example, alkali celluloses, carboxymethylcellulose (CMC) and starch (CMS), cellulose and starch esters and ethers, and aminocelluloses and starches.

Starch is used as the particularly preferred carrier material from this group of detergent ingredients.

Preferably, the amount of solid carrier in the resulting granules accounts for 50 to 80% by weight of the weight of the resulting granules.

worin jede Gruppe R¹ unabhängig voneinander ausgewählt ist aus C_1-6-Alkyl-, -Alkenyl- oder -Hydroxyalkylgruppen; jede Gruppe R² unabhängig voneinander ausgewählt ist aus C_8-28-Alkyl- oder -Alkenylgruppen; T = -O-CO- und n eine ganze Zahl von 0 bis 5 ist.The compositions according to the invention contain as cationic active substances with textile-softening action 5 to 40% by weight of one or more quaternized triethanolamine esters with textile softening formula I:

wherein each R ^{1 group is} independently selected from C _1-6 alkyl, alkenyl or hydroxyalkyl groups; each R ^{2 group is} independently selected from C _8-28 alkyl or alkenyl groups; T = -O-CO- and n is an integer from 0 to 5.

The granules are prepared by placing the solid support in a mixer and then submerged subjected to low energy input with the cationic surfactant. Subsequently, one or more granulation aids are added in the form of an aqueous solution and the mixture is wet-granulated with high energy input.

Low energy input in the sense of the method means slow-running mixing tools or the absence of the use of additional chopping units. This low energy input is further characterized in that the agitator shaft of the mixer does not fluidize the mix, but rather a kind of "cluster mixing" is performed. in which the mix is raised in the mixer in the direction of rotation. High energy input in the sense of the method means a fast rotation of the mixing tools or the use of additional crushing units. In this process, particles are increasingly being whirled from the good bed into the free mixing space and the mixture is fluidized more and more. In this state, the particles fill the mixer in the form of a cloud, the so-called "mechanically generated fluidized bed". At further increasing speeds, the product is finally thrown in the form of a Mischgutrings to the mixer wall, which rotates there.

The method can be carried out in both high-intensity and low-speed mixers, the high-intensity mixers are operated slowly in the first stage of the process and required for the second stage energy input in the low-speed mixers is provided by additional equipment such as knives. Examples of high-speed mixers are the Lödige® CB 30 Recycler, the Schugi® Granulator, the Eirich® Mixer Type R or the Drais® K-TTP 80. Examples of low-speed mixing granulators are the Drais® KT 160 and the Lödige® KM 300. The latter is often referred to as the "Lödige Pflugscharmischer".

As Granulierhilfsmittel which are added in the second stage of the process in the form of aqueous solutions, carboxymethyl cellulosic, water glasses or citric acid are aüsgewählt. With particular advantage, the inventive method uses aqueous solutions of carboxymethyl cellulose (CMC), water glass or citric acid. Depending on the particular granulation aid, the aqueous solutions have different concentrations of the substances used. For example, CMC is used in 0.2 to 5% strength by weight aqueous solutions, water glass in the form of 10 to 40% strength by weight aqueous solutions, and citric acid as 5 to 30% strength by weight aqueous solution.

The granulated particles which are formed during the process can be subjected to the aftertreatment steps customary in detergents and cleaners. For example, drying of the granules in the fluidized bed following granulation is preferred. Also a powdering, rounding or other type of surface treatment can be directly connected to the granulation or to a possible drying

The cationic surfactant granules according to the invention contain from 5 to 40% by weight of one or more textile-softening quaternized triethanolamine esters of the abovementioned formula I, from 50 to 90% by weight of a solid support selected from the group consisting of alkali metal sulfates, carbonates, silicates, citrates and aluminum silicates and citric acid and natural polysaccharides and derivatives thereof and from 0.1 to 5 wt .-% of one or more granulation aids, each based on the weight of the granules.

Preferred cationic surfactant-containing granules contain as solid support component b) sodium sulfate. Granulating agents c) used are one or more substances selected from the group of cellulose derivatives, water glasses or citric acid.

Examples

Various excipients (see table) were placed in a Lödige mixer and mixed at low energy input (without chopper) with the addition of the cationic surfactant. Subsequently, 3 wt .-% aqueous solutions of carboxymethyl cellulose (1%) or water glass (30%) or citric acid (25%), based on the weight of the granules added, and granulated the mixture at high energy input. Following the granulation, the products were dried in the fluidized bed or powdered / rounded. As a comparison, it was attempted to prepare a cationic surfactant compound by impregnation of the respective carriers with cationic surfactant in a mixer. The compositions of the agents after drying are given in Table 1, the physical properties are given in Table 2. Table 1: Composition [% by weight]: E1 E2 E3 E4 E5 V1 Stepantex® VA 90 23,40 18.47 17,01 27,50 22.54 27,70 sodium sulphate - - 82,99 70.60 75.46 71,30 sodium citrate - 81.53 - - - - citric acid 76.60 - - - - - Zeolite P * - - - 1.90 2.00 1.00 Stepantex® VA 90:
Methyl N- (2-hydroxyethyl) -N, N-di (tallowacyloxyethyl) ammonium methosulfate, 95% in isopropanol, from Stepan
CMC: carboxymethylcellulose *: from powdering / rounding Physical Properties E1 E2 E3 E4 E5 V1 Bulk density [g / l] 920 600 1000 875 1065 910 Screen numbers: [%] ** > 1.6 mm 6 25 42 22 10 > 0.8 mm 9 33 47 45 42 > 0.4 mm 18 41 10 23 40 > 0.2 mm 28 1 1 9 7 > 0.1 mm 28 - - 1 1 <0.1 mm 11 - - - - **: The comparison agent was not allowed to dry in the fluidized bed, clumped and therefore gave no grain spectrum.

Further agents according to the invention, the composition of which is given in Table 3, were prepared by the procedure described above; their physical properties are shown in Table 4. Table 3: Composition [% by weight]: E6 E7 E8 E9 E10 E11 Stepantex® VA 90 25.45 - - - - - Stepantex® VL 90 - - 28.27 27.89 - - Stepantex® DC 90 - - - - 28.27 14.14 Dehyquart® AU 48 - 25.45 - - - 14.14 Strength 64.27 64.27 - - - - sodium sulphate - - 70.60 70.42 70.60 70.60 citric acid 1.03 1.03 1.13 1.13 1.13 1.13 carboxymethylcellulose - - - 0.56 - - Zeolite P * - - - - - - water 9.25 9.25 - - - - Stepantex® VA 90:
Methyl N- (2-hydroxyethyl) -N, N-di (tallowacyloxyethyl) ammonium methosulfate, 95% in isopropanol, from Stepan
Stepantex® VL 90:
Methyl N- (2-hydroxyethyl) -N, N-di (tallowacyloxyethyl) ammonium methosulfate, 95% in isopropanol, from Stepan
Stepantex® DC 90:
Methyl N- (2-hydroxyethyl) -N, N-di (oleyloxyethyl) ammonium methosulfate, 90% in isopropanol, from Stepan
Dehyquart® AU 48:
Methyl N- (2-hydroxyethyl) -N, N-di (acyloxyethyl) ammonium methosulfate, 90% in isopropanol, Pulcra *: from powdering / rounding Physical Properties E6 E7 E8 E9 E10 E11 Bulk density [g / l] 650 720 610 585 780 730 Screen numbers: [%] > 1.6 mm 2 21 1 3 1 5 > 0.8 mm 28 45 13 21 33 11 > 0.4 mm 43 22 44 76 24 36 > 0.2 mm 27 12 41 - 41 48 > 0.1 mm - 3 1 - 1 - <0.1 mm - - - - - -

Claims (3)

1. Solid granules containing - based on the weight of the granules -

   a) 5 to 40% by weight of one or more fabric-softening quaternized triethanolamine esters corresponding to formula I:

   

   in which the groups R¹ independently of the other are each selected from C_1-6 alkyl, alkenyl or hydroxyalkyl groups; the groups R² independently of one another are each selected from C_8-28 alkyl or alkenyl groups; T = -O-CO- and n is an integer of 0 to 5,

   b) 50 to 90% by weight of a solid carrier from the group of alkali metal sulfates, carbonates, silicates, citrates and aluminium silicates, citric acid and natural polysaccharides and derivatives thereof,

   c) 0.1 to 5% by weight of one or more granulation aids selected from the group consisting of carboxymethyl cellulose, waterglasses or citric acid.
2. Granules as claimed in claim 1, characterized in that the solid carrier component b) is sodium sulfate.
3. Granules as claimed in any of claims 1 to 2, characterized in that the solid carrier component b) is selected from natural polysaccharides and derivatives thereof, starch being preferred.