WO1991009101A1

WO1991009101A1 - Process for producing a granular, softening detergent additive

Info

Publication number: WO1991009101A1
Application number: PCT/EP1990/002159
Authority: WO
Inventors: Jochen Jacobs; Horst Upadek
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 1989-12-20
Filing date: 1990-12-12
Publication date: 1991-06-27
Also published as: DE3942066A1; EP0506692A1

Abstract

Granular detergent additives with a bulk density greater than 750 g/l and containing (A) 30 to 90 wt.% of a laminar silicate, (B) 1 to 40 wt.% of fine crystalline, synthetic zeolite NaA (referred to the anhydrous substance), (C) 0 to 30 wt.% of water-soluble sodium or potassium salts, the remainder (D) being water, are produced by mixing a dry, powdered to granular constituent (I), in which the constituents (A) and (C) as well as 0 to 50 wt.% (referred to (B) of constituent (B) are present as a homogeneous mixture, with a constituent (II) consisting of a suspension of the remaining constituent (B) containing 90 to 50 wt.% of water, under granulating conditions. The additives have softening and detergent properties.

Description

"Process for the Production of a Granular, Anti-Aging Detergent Additive"

The present invention relates to the production of a granular detergent additive which is distinguished by a high bulk density and, on account of its high proportion of layered silicates, is advantageous, i.e. text has softening properties. Due to its content of ingredients with builder properties, it also has washing properties. Detergent additives of the type mentioned are advantageously added to granular detergents in order to modify and improve their properties. Since detergents with a high bulk density have recently gained particular interest because of the possibility of saving packaging, the particular task was to develop corresponding detergents with a high bulk weight above 750 g / l.

General references to layered silicate agglomerates can be found in DE-A 2439541 (US 3966629), but this document does not provide any specific teaching on the production of granules with a high bulk density.

DE-A 3541410 (US 4582615, US 4609473) discloses textile-softening agglomerates of bentonite and sodium sulfate, containing 1 part by weight of sodium sulfate per 3 to 5 parts by weight Bentonite. In these agents, the sodium sulfate acts as a granulating aid. The agents are produced by granulating the constituents with simultaneous spraying on of water, which is followed by drying of the moist granules by means of hot air, for example in a fluidized bed dryer (fluid bed dryer). The bulk density is specified as 0.2 to 0.9 g / c ^, but in practice (examples) only a maximum bulk density of 0.7 g / 1 is achieved. In addition, the necessary post-drying of the granules is complex.

Detergent builders are known from EP-A 279 040 which contain 50 to 80% by weight of finely crystalline zeolite, 5 to 25% by weight of bentonite and 0.5 to 5% by weight of cellulose ether as binders. In addition, up to 5% by weight of sodium sulfate, up to 1% by weight of alkali and up to 5% by weight of nonionic surfactants can be present. The compositions are prepared by spray drying an aqueous slurry, resulting in a bulk density of only 510 to 540 g / l. Nothing is said about the Aviva effect of the funds. If present at all, it can only be very small since the bentonite content is comparatively small and special layered silicates with an anti-sagging effect are not disclosed.

The object of the present invention is achieved to provide a means which is distinguished both by a good leveling effect and by a high bulk density.

The invention relates to a process for the preparation of a detergent additive which has a washing effect and is effective, with a bulk density of more than 750 g / l (A) 30 to 90% by weight of a layered silicate,

(B) 1 to 40% by weight of finely crystalline, synthetic zeolite NaA (proportion based on anhydrous substance),

(C) 0 to 30% by weight of water-soluble salts from the class of the sulfates, carbonates, silicates and phosphates of sodium or potassium (proportion based on anhydrous substance),

(D) remainder of water by preparing a dry, powdery to granular component (I) in which the components (A) and (C) and 0 to 50% (based on B) of the component (B) are present as a homogeneous mixture, mixed with a component (II) under granulating conditions, this component (II) consisting of a 90 to 50% by weight water-containing suspension of the remaining component (B).

The bulk density of the granules is preferably above 800 g / 1 and in particular above 850 g / 1. By mixing these granules into less dense, for example spray-dried detergent granules, their density can be increased in any desired manner. Despite their high density, the granules disintegrate quickly and completely in water.

Suitable layered silicates (component A), which belong to the group of water-swellable smectites, are e.g. those of the general formulas

(0H) 4 Si ₈ . _y Al _y (Mg _X Al _4. _x ) θ20

Montmorrilonite (0H) Si ₈ _ _y Al _y (Mg _6. _Z Li ₂ ) 020

Hectorite (0H) ₄ Si ₈ . _y Al _y (Mg _6. _z Al _z ) 0 ₂ 0 saponite with x = 0 to 4, y = 0 to 2, z = 0 to 6. In addition, small amounts of iron can be incorporated into the crystal lattice of the layered silicates according to the above formulas. Furthermore, due to their ion-exchanging properties, the layered silicates can contain hydrogen, alkali and alkaline earth ions, in particular Na ⁺ and Ca ⁺⁺ . The amount of water of hydration is usually in the range from 8 to 20% by weight and depends on the state of swelling or the type of processing. The particle size is in the range from 0.05 to 25 μm, usually below 10 μm. Usable layered silicates are known, for example, from US 3966629, US 4062647 (DE 23 34 899-B2), EP 26 529 AI and EP 28 432 AI. Layered silicates are preferably used which, for example due to an alkali treatment, are largely free of strongly coloring iron ions and of calcium ions.

The content of layered silicates in the agents is 30 to 90% by weight, preferably 40 to 80% by weight and in particular 45 to 65% by weight.

The component (B), which is present in proportions of 1 to 40% by weight, preferably 2 to 20% by weight and in particular 2.5 to 10% by weight, consists of synthetic sodium aluminosilicate containing bound water of the zeolite A type. Suitable zeolites have no particles with a size greater than 30 μm and consist of at least 80% particles with a size less than 10 μm. Their calcium binding capacity, which is determined according to DE 24 12 837, is in the range from 100 to 200 mg CaO / g.

The optional component (C) consists, for example, of the sulfates, carbonates, water-soluble silicates and phosphates of sodium and / or potassium. However, the agents are preferably free of phosphates and alkali silicates. Preferred ingredients Group (C) are sodium sulfate and sodium carbonate, both of which are used as anhydrous salts individually or in a mixture and are used as the basis for this calculation. This includes that part of the moisture contained in the granules can be bound to these salts as hydrate water.

The salts mentioned improve the granulability of the starting mixtures and improve the dispersing and dissolving behavior of the granules in the wash water. Their content is preferably 1 to 25% by weight, in particular 5 to 20% by weight.

By definition, the water content of the granules includes the water which is bound to the zeolite (18 to 22% by weight, based on zeolite) and is adsorbed by the layered silicate, and also the water of hydration of the salts. In the case of such granules which have high proportions of layered silicate and correspondingly lower proportions of zeolite, the water content can be reduced to 5% by weight. In the preferred range, i.e. with proportions of approximately 50 to 75% by weight of layered silicate, it is usually 10 to 25% by weight, in particular 12 to 20% by weight. Agents of this composition have the advantage that the granulation using conventional zeolite dispersions containing about 90 to 50% by weight of water, e.g. those according to DE-B 25 27 388 (GB 1 529 713) can be carried out without the granules having to be dried.

As an optional constituent, the agents can contain small amounts of compounds which can be added during the production and processing of the synthetic zeolites in order to increase the stability of the aqueous zeolite dispersions (master batch). Such additives with the zeolite in the middle can be introduced are described in document DE 25 27 388 cited above. These can be nonionic surfactants containing polyglycol ether groups, for example primary alcohols having 12 to 18 carbon atoms reacted with 2 to 7 moles of ethylene oxide. The proportion of stabilizers introduced into the composition via such zeolite dispersions can be, for example, 0.05 to 1% by weight, depending on the proportion of the zeolite. However, this component is not necessary for the desired properties of the granules.

Further optional constituents are dyes or colored pigments, which can be added to the agents in the granulation ^" in proportions of, for example, 0.01 to 1% by weight, in order to cover a possible gray or brownish intrinsic color of the layered silicates After the granules have been mixed into a granular detergent, they give it an optically appealing, color-speckled appearance, and white pigments and, if appropriate, optical brighteners can also be used if a uniform white mixed product is desired.

Dyes which are degraded in the subsequent washing process are particularly suitable, so that there is no undesired dyeing of the textiles. Examples of this are e.g. the dyes duasyn acid blue O) and duasyn acid green (R). The dyes are preferably introduced into the granules together with the water-containing component (II).

Finally, owing to their good absorbency, the granules can be used to adsorb liquid or slurry-like detergent constituents and to be incorporated into detergent granules without loss of free-flowing properties. examples for this are Fragrances, foam-suppressing substances, fatty acid alkanols (which can have an additional softening effect or increase washing power) and nonionic surfactants of the polyglycol ether derivative type. With regard to the amounts of such additives to be applied, however, there is a restriction that additives above about 5% by weight can impair the washing-in behavior of the granules and the granule-containing detergent mixtures in conventional household washing machines. The result of this is that more or less large amounts of washing powder remain undissolved in the induction devices. The amounts of adsorbable material that are still permissible must therefore be checked from case to case. Small proportions of oil-like additives, such as, for example, perfumes or foam-suppressing substances from the class of paraffins, micro-paraffins, long-chain bisacyl diamines and silicones and mixtures thereof, do not lead to corresponding disadvantages.

The production can be carried out continuously or in batch operation using conventional mixing and granulating devices, such as granulating plates, granulating drums and mixing granulators. Preference is given to the use of mixers or mixing granulators with rotating mixing and conveying tools which, by virtue of a high mixing performance in relation to the dry premix and a high energy input into the moist granulating mixture, enable short residence times to be maintained and the formation to be more stable favor homogeneous granules.

Examples of suitable granulating mixers are those from the LÖDIGE company, consisting of a horizontally arranged cylinder with a shaft rotating therein, on which radial mixing tools and, if working continuously, conveyor blades are arranged. Such mixers can also be two or more be connected in series, which enables continuous operation. The dry powder (component I) is premixed in the first mixer and the water-containing component (II) is added in the second, for example via a screw conveyor or by means of nozzles, and the granulation is carried out.

When the constituents (A), (C) and, if appropriate, a dry portion of (B) are mixed, it is possible to start from powdery starting materials or else from pregranulated products. Pre-granulated layered silicates and optionally pre-granulated zeol th offer the advantage of largely dust-free working and easier transportation and dosing. The formation of homogeneous granules is not adversely affected since the mixing and granulation process largely leads to a breakdown of the predetermined granulate state and to a new build-up of the granules.

The powdery or granular component (I) can consist exclusively of the layered silicate (A). This applies in particular to the case where a high content of (A) is sought in the end product, for example that of 80 or more percent by weight. If lower levels of layered silicate and higher proportions of zeolite are desired, for example in order to improve the washing effect in very hard, ie calcium-rich tap water, it may be advantageous to dry part of the zeolite (B) in a dry, preferably granular form to introduce the dry premix (I). This procedure is recommended for contents of 30 and 50% by weight (A) and 25 to 40% by weight (B) in the finished granulate. In this way, it is possible to introduce a relatively large amount of zeolite into the granules without at the same time introducing the zeolite suspension into the granules The amount of water is increased excessively and subsequent drying is necessary.

In the preferred range from 40 to 80% by weight, in particular from 45 to 65% by weight, of layered silicate, the addition of dry zeolite is neither necessary nor appropriate. Rather, it is preferred in these areas to introduce the zeolite (B) exclusively in the form of an aqueous dispersion. This saves at the same time the energy for pre-drying the zeolite filter cake, which is still moist from its manufacture, and additional storage and metering devices for the dry zeolite.

It follows that the aqueous component (II) preferably contains 75 to 100% and in particular 100% of the total zeolite (B) used.

In the particularly preferred range of 40 to 80% by weight of layered silicate and 2 to 10% by weight of zeolite, the proportion of water-soluble salts, in particular sodium sulfate and sodium carbonate, is preferably 10 to 20% by weight in each case based on the finished granules.

The mixing of the dry component (I) takes about 10 to 60 seconds, usually 15 to 45 seconds, in the described mixing and granulating devices. Then the aqueous component (II) is added and the mechanical processing is continued until stable, free-flowing granules are formed. These process steps require approximately 30 seconds to 3 minutes, usually 1 to 2 minutes for metering in, which is carried out with constant mixing of the granulated material, and approximately 10 seconds to 1.5 minutes, usually 15 to 60 seconds, for re-granulation after the addition has ended the aqueous component (II). The granulate is then ready for use or can be processed further in a suitable manner.

The water content of component (B), which includes the water content (loss on ignition) bound to the zeolite, is 90 to 50% by weight and is dependent on how much water is needed to form usable granules and how much water in the finished granules is tolerated. If the zeolite contents in the end product are low, for example those below 10% by weight, water-rich suspensions will be used, for example those with 70 to 90% by weight, in particular 75 to 85% by weight of water (including the water bound to zeolite). . In the case of granules with a high proportion of zeolite, lower water zeolite dispersions are recommended, for example those with 70 to 50% by weight of water.

Post-drying of the granules is not necessary or is only indicated when a high level of layered silicate in the granules is desired, for example that of over 75% by weight, in particular from 80 to 90% by weight. Conventional drying devices operated with heated air, for example fluidized bed dryers, are suitable for this less preferred process step.

The average grain size of the granules is usually 0.2 to 1.2 mm (RRSB determination according to DIN 66 141, according to IS0 / DIS 9276-1-1988), the proportion of the grains below 0.1 mm not more than 5 % By weight and above 2 mm not more than 10% by weight. Preferably, at least 80% by weight, in particular at least 90% by weight, of the grains have a size of 0.2 to 2.0 mm, the proportion of the grains below 0.1 mm not more than 2% by weight, in particular not more than 1% by weight and the proportion of Grains above 2 mm is not more than 10% by weight, in particular not more than 5% by weight. Larger proportions of fine grain generally lead to a deterioration in the induction behavior and should therefore be avoided. If the raw granules contain corresponding proportions of coarse and fine grains, these are sieved and, after grinding the coarse grains, returned to the process (as an additional component of component I). This has no disadvantages for the granulation process and the quality of the granules.

The granules are free-flowing, largely dimensionally stable and can be mixed in with conventional granular detergents in any ratio. In order to achieve a softening effect which is perceived by the consumer as sufficient, it is generally sufficient if the finished detergent contains 5 to 30% by weight, preferably 10 to 25% by weight, of layered silicate.

B e i s p e l e

The mixing and granulating process was carried out in a horizontally arranged, cylindrical granulating mixer (type LÖDIGE), in the longitudinal axis of which a shaft equipped with mixing tools rotated at a speed of 180 rpm. The internal volume of the mixer was 130 liters. The products "Dis-Thix-Extra" from Schwegmann / Germany (short name SI) and "Laundrosil DG-A" from Südchemie / Germany (short name S2) were used as layered silicate. The synthetic zeolite of the NaA type had a calcium binding capacity (determined according to the information in DE 24 12 837) of 165 mg CaO / g and an average grain size of 3 μm (no proportions above 20 μm). The starting material was an aqueous dispersion containing about 50% by weight of water and 2% by weight of a 5-fold ethoxylated tallow fatty alcohol (as dispersion stabilizer). The zeolite used in the dry form as a component of component (I) contained 20% by weight of water in the form of water of hydration and was in the form of spray-dried granules (average grain size 0.4 mm). The dye (duasynic acid green) was dispersed in the zeolite suspension.

The type and amount of the starting materials used, the process parameters and the product properties are summarized in the following table. Sodium sulfate and sodium carbonate were used in anhydrous form. The zeolite is calculated as an anhydrous substance. Nonionic is the non-ionic dispersion stabilizer. “Premixing” is understood to mean the period of time that was spent on homogenizing the dry constituents (layered silicate to zeolite granules). "Mix in" indicates the period of time during which the aqueous zeolite dispersion was mixed in uniformly. "Granulation" denotes the time in which after the suspension had been added completely, the mixture was further granulated until the emptying phase began. Unless stated otherwise, the percentages relate to percentages by weight, based on the total granulate. If the grain distribution of the raw granulate (see table) was not in the desired range (not more than 10% above 2 m and not more than 2% below 0.1 mm), the coarse grain and / or the fine grain became the same sieved that 83 - 95% of the granules had a grain size of 2 - 0.2 mm, the proportion of coarse grain> 2 m 3 to 7% and the proportion of fine grain was 0.5 to 2%. The bulk density refers to the remaining fraction after separating the coarse and fine particles.

All of the granules were stable and free-flowing without the need for drying. After mixing the granules into a spray-dried, phosphate-free heavy-duty detergent (proportion of layered silicate in the complete mixture 15% by weight), satisfactory finishing effects on the washed textiles were found in washing tests. The washing effect (degree of whiteness of the textiles) was not reduced by this addition, which inevitably leads to a reduction in the concentration of all washing-active ingredients contained in the original heavy-duty detergent.

Examples

Feature 1 2 3 4 5

Layered silicate Sl 60.8 64.0 - 49.6

Layered silicate S2 - - 74.1 - 60.0

Na ₂ S04 - 16.0 8.2

Na ₂ C03 15.2 - - 9.6 12.5

Zeolite granules - 12.0

Zeolite from suspension 4.8 4.0 1.8 13.1 10.0

Water from suspension 19.05 15.78 15.85 15.2 18.2

Nonionic 0.15 0.12 0.05 0.4 0.3

Dye - 0.1 - 0.1

Premixing (sec) 20 Mixing (sec) 120 Post-granulation (sec) 30

Product quantity (kg) 13.2 25.5 20.5 25.0 25.0 Grain size (%) Raw organic material> 2 mm 7

2 - 0.2 mm 83

<0.2 mm 10

Bulk density (g / 1) 920 900 91Q 909 902

Claims

Expectations

1. A process for the preparation of a detergent additive which has a washing effect and is granular and has a bulk density of more than 750 g / l

(A) 30 to 90% by weight of a layered silicate,

(D) remainder of water by using a dry, powdery to granular component (I) in which the components (A) and (C) and 0 to 50% (based on B) of the component (B) as homogeneous Mixture, mixed with a component (II) under granulating conditions, this component (II) consisting of a suspension of the remaining constituent (B) containing 90 to 50% by weight of water.

2. A process for the preparation of an agent according to claim 1, wherein component (A) consists of smectites, the proportion of which is 40 to 80% by weight, in particular 45 to 65% by weight.

3. A method for producing an agent according to claim 1 or 2, wherein the proportion of component (B) is 2 to 20 wt .-%, in particular 2.5 to 10 wt .-%.

4. The method according to claim 1 to 3, wherein the component (B) 100% in the form of a dispersion containing 10 to 50 wt .-% water is used as component (II).

5. A process for the preparation of an agent according to one or more of claims 1 to 4, wherein component (C) consists of 1 to 25% by weight, preferably 5 to 20% by weight, of sodium sulfate, sodium carbonate or mixtures thereof .

6. A process for the preparation of an agent according to one or more of claims 1 to 5, wherein the proportion of water is 10 to 25% by weight.

7. A process for the preparation of an agent according to one or more of claims 1 to 7, wherein a dye or a pigment in amounts of 0.01 to 1 wt .-%, based on the agent, in the aqueous component (II ) brings.

8. Agent produced according to one or more of claims 1 to 7.

9. Use of an agent according to claim 8 as an adjuvant in granular detergents.

10. Granular detergent containing 10 to 25 wt .-% of the agent according to claim 8.