WO1993018127A1

WO1993018127A1 - Process for thickening non-aqueous liquid washing and cleaning agents

Info

Publication number: WO1993018127A1
Application number: PCT/EP1993/000483
Authority: WO
Inventors: Wolfgang Breuer; Helmut Endres; Thomas Förster; Michael Schaaf
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 1992-03-12
Filing date: 1993-03-03
Publication date: 1993-09-16
Also published as: DE4207802A1

Abstract

Hydrophobised hydrotalcites are effective thickening agents for non-aqueous liquid washing and cleaning agents with a high concentration of active substance.

Description

"Process for thickening non-aqueous liquid washing and

Cleaning supplies"

The present invention relates to a process for thickening non-aqueous liquid detergents and cleaning agents, in which hydrophobicized hydrotalcite, which can be prepared by certain different processes, is used as the thickener.

Liquid detergents are often preferred to powdery products for various reasons, for example because they are easier to dose, because they do not dust during handling and because they often take up less space during storage. A disadvantage of liquid detergents containing solids is their tendency to sediment during storage. Difficulties in redispersing are often associated with this. It is therefore important that such suspensions are stabilized by suitable organic or inorganic thickeners. Depending on whether the suspensions are aqueous or non-aqueous, different agents are used for stabilization. For non-aqueous liquid detergents, for example, DE-A-38 20 631 cellulose ethers, acrylic and acrylamide polymers or colloidal clays or bentonites or montmorillonites treated with quaternary ammonium compounds have been proposed. For aqueous systems, international patent application WO 89/08693 Hydrotaltice or comparable double-layer hydroxide phases are known as viscosity regulators. DE-C-37 91 919 describes aluminum-magnesium-hydroxy compounds as thickeners for paints, varnishes, paints and the like. From DE-A-37 32 265, aluminum-magnesium-hydroxy compounds are known as theological additive and anti-settling agent for cosmetics. In DE-A-40 10 606 Hydrophobicized hydrotalcites, which belong to the group of double-layer hydroxides, are described as catalysts for the ethoxylation or propoxylation. Finally, DE-A-39 14 960 discloses hydrophobicized hydrocite as an additive to drilling fluid. Aluminum-magnesium-hydroxy-fatty acid compounds are described for the production of thermostable gels for cosmetic and pharmaceutical use (DE-A-39 32 377). It was not apparent from this prior art that hydrophobized hydrotalcites are suitable for thickening non-aqueous liquid washing and cleaning agents.

The present invention therefore relates to a process for thickening non-aqueous liquid detergents and cleaning agents, which is characterized in that hydrophobicized hydrotalcite can be prepared by one of the following processes

a) reacting hydrotalcite with fatty acid in solvents; b) direct reaction of hydrotalcite with fatty acid in mixing units; c) synthesis of magnesium salt and aluminum salt in aqueous solution of alkali hydroxide containing fatty acid alkali salt; d) reacting calcined hydrotalcite with a solution of fatty acid or its alkali salt

used.

The hydrophobicized hydrocatalysts which can be prepared by the abovementioned processes are all equally suitable for the process according to the invention for thickening non-aqueous liquid detergents and cleaning agents. The hydrophobicized hydrotalcites which can be prepared in this way have the following idealized general formula I.

[Mgι_ _x Al _x (0H) 2] A _a B _b .zH20 (I)

in which A represents an equivalent of an aliphatic monocarboxylic acid having 2 to 34 carbon atoms and the conditions 0, 1 <x 0, 5 0 <a <0, 5 0 b <0, 5 0 <(a + b) <0, 5 0 <z <10

be valid .

In this respect, the hydrophobized hydrotalcites that can be used for the process according to the invention correspond to the products described in more detail in DE-A-4010606.

Hydrotalcite is a natural mineral with the ideal molecular formula ^M 96 ^A 12 ( ^0H ) 16 ^C0 3 • ^4H 2 ° 'whose structure is derived from that of brucite (Mg (0H) 2). Hydrotalcites continuously release water when heated or calcined. The drainage is complete at 200 ° C., it being possible to prove by X-ray diffraction that the structure of the hydrotalcite has been preserved.

A preferred embodiment of the process according to the invention is characterized in that hydrophobicized hydrotalcite, which is obtained by reacting 1 mol of hydrotalcite of the idealized su formula, suspended in organic solvents, with 0.5 to 4 mol of a fatty acid with 6 to 30 , preferably with 6 to 22 carbon atoms, dissolved in organic solvents at elevated temperature, separating off the solid, washing and drying at 90 to 120 ° C. under reduced pressure to constant weight. Organic solvents which are sufficiently inert, for example isopropyl alcohol, are suitable for suspending the hydrotalcite. Isopropyl alcohol is also a suitable solvent in many cases for dissolving the fatty acid with which hydrotalcite is made hydrophobic. In the case of longer-chain fatty acids, it may be appropriate to use a different solvent, for example tetrahydrofuran, instead of isopropyl alcohol. Instead of organic solvents, water can also be used in some cases. This is also a preferred embodiment of the method according to the invention. It is two for the reaction of the hydrotalcite with the hydrophobizing agent moderate to work at elevated temperature. The reflux temperature is recommended for relatively low-boiling solvents. When using higher leather solvents, it may be advisable to set a temperature lower than the reflux temperature. However, hydrophobic hydrotalcites which have been prepared without the use of solvents are also suitable for carrying out the process according to the invention. This is done by directly reacting hydrotalcite, for example with fatty acid, in mixing units such as kneaders and mixers at elevated temperature. Depending on the degree of hydrophobization, hydrotalcite can be reacted with different amounts of fatty acid. In many cases it is expedient to react about 2 to 10% by weight of fatty acid, based on hydrotalcite, with the hydrotalcite. Hydrophobicized reaction products with less or more fatty acid, for example up to about 70% fatty acid, based on hydrotalcite, can also be prepared without difficulty.

The process according to the invention can also be carried out using hydrophobic hydrotalcite, the hydrotalcite of magnesium and aluminum salts in aqueous solution of alkali metal hydroxide which contains fatty acid alkali metal salt. Suitable magnesium or aluminum salts are, for example, the nitrates, which are readily soluble in water. Suitable fatty acid alkali salts are derived from fatty acids with 6 to 30 carbon atoms. When the reaction constituents are mixed, a precipitate forms, which is expediently dried after separation and washing out at 90 to 120 ° C. and reduced pressure of about 50 to 200 mbar.

Also hydrophobicized hydrotalcite, which is obtained by calcining hydrotalcite at 300 to 600 ° C., suspending the calcined hydrotalcite in water, reacting with a solution or a suspension of the alkali salt of a fatty acid or a fatty acid with 6 to 30 carbon atoms 60 to 90 ^β C, separating the solid has, washing and drying at 90 to 120 ° C under a pressure of 50 mbar to 200 prepared, the inventive method is suitable for implementation. A temperature suitable for calcination is, for example, 500 ° C., which is left to act on the hydrotalcite for about 2 hours while losing water and CO2. The fatty acid used to make the calcined hydrotalcite hydrophobic n organic solvents, isopropyl alcohol spielsweise ^solved is either water or ^is.

Another object of the present invention is the use of hydrophobized hydrotalcite, produced by one of the previously described methods for thickening non-aqueous liquid detergents and cleaners in a concentration of 0.05 to 5, preferably 0.5 to 3 % By weight of hydrophobicized hydrotalcite, based on the washing and cleaning agent. Non-aqueous liquid detergents or cleaning agents have the advantage over aqueous agents that they can be prepared with a higher active ingredient content than aqueous agents and that they can also contain, for example, the bleaching agents based on peroxide compounds which are unstable in aqueous agents. The hydrophobized hydrotalcite is mixed with the liquid washing and cleaning agent by grinding, for example in a ball mill. A concentration-dependent increase in the yield point and viscosity, which have a particularly low temperature dependence, is observed in the products obtained in this way.

B e i s p i e l e

The following examples describe various methods for the production and use of hydrophobic hydrotalcites which can be used according to the invention.

example 1

This example describes the hydrophobization of hydrotalcite in solvents.

50 g of hydrotalcite from Giulini were suspended in 250 ml of isopropyl alcohol and within 30 minutes with a solution of a) 55 g of oleic acid, b) 33.2 g of lauric acid and c) 19.5 g of caproic acid in 200 ml of isopropyl alcohol at room temperature. After heating to the reflux temperature, an evolution started. After the evolution of gas had ended, the mixture was left to react for a further two hours. After cooling, the suspension was then filtered. The filter cake was washed with isopropyl alcohol and dried in a drying cabinet at 105 ° C and dried to constant mass at a reduced pressure of 100 mbar.

In the case of longer-chain fatty acids, it may be expedient to use a different solvent instead of isopropyl alcohol. For example, 50 g of hydrotalcite was reacted with 72.1 g of TMUL, Hoechst, (calculated as C27H55C00H), dissolved in 600 ml of tetrahydrofuran. Instead of organic solvents, water can also be used. For example, lauric acid was dissolved in hot water. After heating to approx. 80 ° C, gas evolution started. The reaction mixture was kept at this temperature until the evolution of gas had ended. The solid portion was filtered off hot; it was washed with hot water and dried as described above. The analytical determination of the magnesium, aluminum, carbon and hydrogen content gave the expected values.

X-ray diffraction diagrams showed the layer structure of the compounds, infrared spectra the expected bands.

Example 2

This example describes the hydrophopation of hydrotalcite without the use of solvents. 50 g of hydrotalcite from Giulini were processed with 5 g of lauric acid or 5 g of behenic acid for one hour at 80 ° C. in a knee. After cooling, powdery products resulted. In the same way, hydrophobicized reaction products with less and with more fatty acid, for example up to about 70% fatty acid, based on hydrotalcite, can be produced.

X-ray diffraction diagrams showed the layer structures of the compound.

Example 3

This example describes the preparation of hydrophobic hydrotalcite by synthesis of the hydrotalcite.

To solutions of 65 g of 50% sodium hydroxide solution and a) 30.4 g of sodium oleate, b) 22.2 g of sodium laurate and c) 13.8 g of sodium caprohate, in each case 400 ml of water, a solution of 77 was obtained with vigorous stirring , 0 g Mg (N03) 2-6H20 and 37.5 g Al (N03) 3.9H20 in 300 ml water were added dropwise within 90 minutes. A white precipitate formed spontaneously. The suspension thus obtained was annealed at 70 ° C for 15 hours. After filtering off and washing with water, the precipitates obtained were dried in a drying cabinet at 105 ^° C. and 100 mbar.

X-ray diffraction diagrams showed the layer structures of the compound.

Example 4

Like example 3, this example describes the preparation of hydrophobic hydrotalcite by synthesis. The solutions of 307.7 gg (Nθ3) 2-6H2θ and 150.0 g Al (Nθ3) 3.9H2θ in 8 l water were mixed with the solutions of 300 g 50% sodium hydroxide solution and a) 136.2 g behenic acid, b) 113.0 g of oleic acid, c) 80.1 g of lauric acid and d) 143.0 g of technical rapeseed oil-split fatty acid in 8 l of water each pumped through a Y-piece and reacted. White suspensions were obtained, which were filtered off and washed. It was dried at 105 ° C and 100 mbar.

In this case, too, the X-ray diffraction diagrams showed the typical visual structures.

Example 5

This example describes the preparation of hydrophobic hydrotalcite from caleined hydrotalcite.

Hydrotalcite was calcined at 500 ° C for two hours. A mass loss of water and CO2 of approx. 60% occurred.

10 g of the hydrotalcite calcined as above were suspended in 100 ml of water and a solution of 13.3 g of sodium laurate in 100 ml of water was added at room temperature. After the entire solution had been added, the suspension was heated to 7 ° C. for two hours, then allowed to cool, the suspension was filtered and the filter cake was washed with water until the wash water indicated a pH of 10. The Fil¬ terrückstand was to constant weight at 110 C and 100 mbar ^β getrock¬ net. The analytical determination of the magnesium, aluminum, sodium, carbon and hydrogen content and the X-ray diffraction diagrams showed the expected results.

Example 6

This example also shows the preparation of hydrophobic hydrotalcite from calcined hydrotalcite.

20 g of the calcined hydrocetal kit prepared as described in Example 5 were suspended in 200 ml of water and a solution of 25 g of lauric acid in 100 ml of isopropyl alcohol was added. The reaction mixture was heated to 70 ° C. for three hours, the mixture was allowed to cool and the suspension was filtered off. After washing the filter cake with isopropyl alcohol, the mixture was dried to constant weight at 110 ° C. and 100 mbar.

Example 7

This example describes the thickening effect of the hydrophobized hydrotalcites on a non-aqueous detergent of the following composition:

15.0% alkylbenzenesulfonate sodium

26.2% lauryl alcohol with 3 moles of ethylene oxide

26.2% Ci2-Ci8 fatty alcohol with 5 moles of ethylene oxide

6.0% l-methoxy-2-propanol

0.5% triacetin

10.0% sodium perborate monohydrate

3.0% Sokalan CP5

4.0% TAED

4.0% sodium carbonate

0.2% silicone oil dispersant

The disperser was milled in different amounts together with the other solids in the ball mill and the theological properties were measured on the following day. The hydrophobicized hydrotalcites, which act as dispersants, were mixed into the detergent in different amounts. The yield point and the viscosity of the detergents were given at 30s ~ l, measured with a Carri ed viscometer. Before the milling in the ball mill the hydrophobic hydrotalcite was ^β at 200 C and 100 mbar removed within 2 hours water of crystallization.

Dispersant I is hydrotalcite which has been hydrophobicized with oleic acid in isopropanol. Dispersant II is hydrotalcite which has been hydrophobized in water with lauric acid. Dispersant III is hydrotalcite, which was reacted with 40% lauric acid in a kneader. The information in Table 1 below shows how viscosity and yield point are influenced by hydrophobic hydrotalcite, an increase in the yield point being associated with improved sedimentation stability.

Table 1

Example 8

An anhydrous mixture of the following composition was mixed with different amounts of hydrophobized hydrotalcite and the flow limit and viscosity were measured as described in Example 1:

55% by weight metasilicate, anhydrous

5% by weight maleic anhydride / acrylic acid copolymer

1% by weight of hydroxyethyldiphosphonic acid

1% by weight carboxymethy1ce11u1ose / methy1ce11u1ose mixture of hydrophobicized hydrotalcite

Rest 2: 1 mixture of lauryl alcohol + 3 moles of ethylene oxide

+ Propylene oxide

Product II from Example 1 was used in various concentrations as the hydrophobicized hydrotalcite. The results listed in Table 2 were obtained.

Table 2

In comparison to the other known thickeners, systems thickened with hydrophobic hydrotalcite have a lower temperature dependency on the yield point and viscosity.

Claims

1. A process for thickening non-aqueous liquid washing and cleaning agents, characterized in that hydrophobicized hydrotalcite can be prepared by one of the following processes:

a) reacting hydrotalcite with fatty acid in solvents; b) direct reaction of hydrotalcite with fatty acid in mixing units; c) synthesis from magnesium salt and aluminum salt in an aqueous solution of alkali hydroxide which contains fatty acid alkali salt; d) reacting calcined hydrotalcite with a solution of fatty acid or its alkali salt;

used.

2. The method according to claim 1, characterized in that hydrophobicized hydrotalcite, prepared by reacting 1 mol of hydrotalcite, suspended in organic solvents with 0.5 to 4 mol of a fatty acid with 6 to 30, preferably with 6 to 22 Carbon atoms, dissolved in organic solvents at elevated temperature, separating off the solid, washing out and drying at 90 to 120 ° C. under reduced pressure to constant weight.

3. The method according to claim 1, characterized in that hydrophobicized hydrotalcite, prepared by reacting hydrotalcite with fatty acid having 6 to 30, preferably having 6 to 22 carbon atoms, dissolved in water at elevated temperature, separating the solid, washing out and drying at 90 to 120 ° C under reduced pressure to constant weight.

4. The method according to claim 1, characterized in that hydrophobicized hydrotalcite, prepared by reacting hydrotalcite with fatty acid in the absence of solvents in the kneader or mixer at elevated temperature, is used.

5. The method according to claim 1 or 4, characterized in that hydrophobicized hydrotalcite, prepared by reacting Hydrotal¬ cit with 2 to 70 wt .-% fatty acid, based on hydrotalcite, is used.

6. The method according to claim 4 or 5, characterized in that hydrophobized hydrotalcite, prepared by reacting at 60 to 120 ° C, preferably at 70 to 90 ° C, is used.

7. The method according to claim 1, characterized in that hydrophobed hydrotalcite, prepared by mixing aqueous solutions of alkali metal hydroxide, magnesium salt, aluminum salt and the alkali metal salt of a fatty acid having 6 to 30 carbon atoms, separating the solids, washing out and drying at 90 up to 120 ^β C under reduced pressure of 50 to 200 mbar.

8. The method according to claim 1, characterized in that hydrophobicized hydrotalcite, prepared by calcining hydrotalcite at 300 to 600 ° C, suspending the calcined hydrotalcite in water, reacting with a solution or suspension of the alkali metal salt of a fatty acid or one Fatty acid with 6 to 30 carbon atoms at 60 to 90 ^° C, separating the solid, washing and drying at 90 to 120 ^° C under a pressure of 50 to 200 mbar.

9. The method according to claim 8, characterized in that one uses hydrophobic hydrotalcite, produced by reacting calcined hydrotalcite with an aqueous solution of the alkali salt of a fatty acid.

10. The method according to claim 8, characterized in that hydrophobicized hydrotalcite, prepared by reacting calcined hy- drotalcite with a solution of alkali salt of a fatty acid in alkanol used.

11. Use of hydrophobicized hydrotalcite, prepared by a process according to one of claims 2 to 10 for thickening non-aqueous liquid detergents and cleaning agents according to claim 1, characterized in that 0.05 to 5, preferably 0.5 up to 3 parts by weight of hydrophobicized hydrotalcite, based on the washing and cleaning agent.