EP0710272B1 - Process for producing softening dispersions - Google Patents

Abstract

It has been discovered that aqueous dispersions of cationic textile softening compounds of the type of the quaternary ammonium compounds have a particularly stable viscosity when the rheological data correspond to the formula lg y = - k . lg tan o + A, in which y stands for the viscosity and tan o for the ratio (G"/G') between the loss module G" and the storage module G'. A process is thus disclosed for producing aqueous textile softener dispersions with a stable viscosity set in the range given by the formula by known influencing quantities, for example the intensity and the duration of the shearing process.

Description

The invention relates to a method for Testing the stability and viscosity consistency of dispersion-cationic textile plasticizer compounds and the application of the procedure in the manufacture of viscosity-stable, aqueous Fabric softener dispersions.

Cationic quaternary type plasticizer compounds Ammonium compounds with two or three lipophilic alkyl, alkenyl, Acyloxyalkyl or acylaminoalkyl groups are little in water soluble. They are therefore usually in aqueous dispersions brought the trade, which dilute slightly further with water to let. The production of these dispersions by conventional dispersion processes however, often leads to dispersions that occur in the course change their viscosity significantly within a few hours or days. Most of the time one observes a strong thickening, thereby the lose Dispersions their fluidity or pumpability and thus also their easy dilutability with water.

Therefore, studies have been carried out that are related between the rheology of such dispersions and the conditions of Dispersion production should show, so a targeted production viscosity-stable dispersions of cationic fabric softener compounds becomes possible.

It was surprisingly found that when the viscosity (y) of the softener dispersion is plotted against the parameter in a double logarithmic manner tan δ a linear relationship results if the conditions of constant viscosity are given. This relationship is given by the straight line according to formula I. lg y = - k · lg tan δ + A

It is tan δ the ratio (G '' / G ') of the loss module G''to the memory module G'. The rheological parameters G '' (loss module) and G '(storage module) are the characteristic parameters of a viscoelastic liquid.

For the quaternary ammonium compounds commonly used is the position of this straight line through the slope k and the ordinate section A defined.

The invention therefore relates to a method for testing the stability of dispersions of cationic fabric softening compounds of the quaternary ammonium compound type with at least two groups having 12-22 C atoms, selected from alkyl, alkenyl, acyloxyalkyl or acylamidoalkyl groups, characterized in that that the viscoelastic parameters G '' (loss modulus) and G '(storage modulus) are determined and based on the relationship according to formula I. lg y = - k · lg tan δ + A in the tan δ is the ratio of G '' / G 'and k and A are system constants which are determined by producing different viscosity constant dispersions of the cationic fabric softening compound in question and from the graphical plot of lg y over lg tan δ read the slope k and the ordinate section A of the resulting straight line, calculate the viscosity y and check whether the measured viscosity corresponds to the calculated viscosity.

Leave for any cationic fabric softener compound the guide values for increasing the straight line k and for the Easily determine ordinate section A by using dispersions manufactures according to the usual method and the manufacturing parameters (Concentration, electrolyte content, type of perfume oil) changes several times and the homogenization, especially the duration and intensity of the Shear increases until a constant viscosity occurs. In this way, points of a straight line according to formula I are obtained which can then be taken from the guide values for k and A.

If for a particular cationic fabric softening compound Position of the straight line, i.e. the guide values for k and A are determined, can be used for further dispersions of this raw material based on the rheological Parameters G '(storage module), G' '(loss module) and viscosity y easily determine from the relationship of Formula I whether the dispersion will be viscosity stable - or whether the rheology of the system can only be set in the range according to the invention got to.

The rheology is set in the range according to the invention generally by known measures: it is known that by increasing the shear forces, i.e. through intensive mixing and homogenization work the particle size of the dispersion is reduced and the Viscosity can be changed. It is also known that at Temperatures above the melting point of the to be dispersed Substances the dispersion and particle size reduction takes place more quickly.

It is also known that the duration of the shear or the stirring time to intensify the homogenization and to influence contributes to the viscosity. Finally, the structure of the to be dispersed substrate or its composition and the Addition of additives influence the dispersibility. For example, a lowering of the melting point of the fabric softening composition to be dispersed an effect similar to an increase in Dispersing temperature. Also lowering the viscosity of the melted Fabric softener composition leads to faster Particle size reduction.

It is therefore possible to change the viscosity and the rheological properties influenced by numerous parameters in the dispersion. To answer the question of whether a particular dispersion when stored will be stable in viscosity, is therefore the invention method helpful.

Given the structure and composition of the to be dispersed The viscosity of the substrate is preferred by intensity and duration shear work, e.g. by stirring, if necessary using homogenizers set. Other preferred measures are temperature control and the use of additives, e.g. of electrolyte additives, Glycols, water-soluble polymers and other known Additives to influence the viscosity of aqueous dispersions.

verwendet werden, in der im Mittel 2 bis 3 der Gruppen R¹ bis R⁴ der Formel R⁵CO(OC_nH_2n)_x ^- entsprechen, in der R⁵CO eine Acylgruppe mit 12 - 22 C-Atomen, n = 2 oder 3 und x = 1 bis 10 sein kann, und die übrigen Alkylgruppen mit 1 - 4 C-Atomen und/oder Hydroxy-(alkoxy)-alkylgruppen der Formel H-(OC_nH_2n)_x ^- sind, in der n und x die genannte Bedeutung haben und A^(-) ein Chlorid oder CH₃OSO₃ ^(-)-Anion ist. Besonders bevorzugte Textilweichmacher-Verbindungen dieses Typs sind solche, die durch Umsetzung von Triethanolamin mit Fettsäureestern und anschließende Quaternierung des Umsetzungsprodukts mit Methylchlorid oder Dimethylsulfat zugänglich sind. Als Fettsäureester sind dabei z.B. die Methylester von Fettsäuren mit 12 - 22 C-Atomen, z.B. von natürlichen Fettsäuregemischen wie Palmölfettsäure oder Talgfettsäure geeignet. Die Umesterung von Triethanolamin mit Fettsäuremethylestern führt, auch wenn sie im Molverhältnis 1 : 2 bis 1 : 3 durchgeführt wurde, zu Gemischen von Mono-, Di- und Triestern des Triethanolamins, die bezüglich des Gehalts an Acyloxyethylgruppen nur im Mittel dem Umsetzungsverhältnis entsprechen.The linear relationship found between lg y and tan δ applies particularly well when textile softener compounds of the type of the quaternary ammonium compounds of the general formula II

are used in which on average 2 to 3 of the groups R ¹ to R ⁴ correspond to the formula R ⁵ CO (OC _n H _2n ) _x ^- , in which R ⁵ CO is an acyl group with 12-22 C atoms, n = 2 or 3 and x can be 1 to 10, and the other alkyl groups with 1-4 carbon atoms and / or hydroxy (alkoxy) alkyl groups of the formula H- (OC _n H _2n ) _x ^- , in which n and x have the meaning given and A ^{(-) is} a chloride or CH ₃ OSO ₃ ^(-) anion. Particularly preferred textile softener compounds of this type are those which are accessible by reacting triethanolamine with fatty acid esters and subsequent quaternization of the reaction product with methyl chloride or dimethyl sulfate. Suitable fatty acid esters are, for example, the methyl esters of fatty acids with 12-22 carbon atoms, for example of natural fatty acid mixtures such as palm oil fatty acid or tallow fatty acid. The transesterification of triethanolamine with fatty acid methyl esters, even if it was carried out in a molar ratio of 1: 2 to 1: 3, leads to mixtures of mono-, di- and triesters of triethanolamine which correspond to the reaction ratio only on average in terms of the content of acyloxyethyl groups.

worin R⁵CO eine von Talgfettsäure oder Palmkernfettsäure abgeleitete Acylgruppe ist. Diese ist im Handel unter der Handelsbezeichnung Stepantex^(R) VS 90 (Firma STEPAN) erhältlich. Für dieses Produkt betragen die Richtwerte für die Steigerung k und den Ordinatenabschnitt A in der Formel I k = 2,9 ± 0,3 und A = 2,3 ± 0,3.A particularly preferred textile softener compound corresponds on average to formula III

wherein R ⁵ CO is an acyl group derived from tallow fatty acid or palm kernel fatty acid. This is commercially available under the trade name Stepantex ^(R) VS 90 (company STEPAN). For this product, the guideline values for the increase k and the ordinate section A in the formula I are k = 2.9 ± 0.3 and A = 2.3 ± 0.3.

When using this textile softener raw material e.g. detected be that the cis / trans ratio of the acyl groups (oleoyl to elaidoyl groups) have a positive effect on the rheological behavior affects, i.e. the higher the proportion of oleoyl groups, the less Shear energy (stirring time) is required to do the rheological Behavior in the range according to the invention corresponding to formula I. bring to. 30-70% of the unsaturated acyl groups are preferably present in the cis form.

Another factor is the concentration. So was the example the aforementioned compound of formula III found that the viscosity of the dispersion when the softener concentration is increased rises sharply. Particularly desirable in terms of application technology Viscosities were at a concentration of 5-20 wt .-% of dispersed fabric softener found. At higher concentrations is a longer stirring time and / or higher shear work necessary to uni the dispersion in the range of the invention bring in a high storage stability and constant viscosity given is.

Additives such as e.g. Electrolytes, Dispersing agents or fragrances. During the influence of electrolytes and dispersing aids (emulsifiers) on the viscosity and stability of dispersions are largely known an increase in viscosity can be determined by adding perfume oil, which was still dependent on the addition temperature of the perfume oil. Perfume oils are usually used to avoid fragrance losses added last and at low temperatures.

Regardless of the options mentioned, the viscosity of Influencing fabric softener dispersions can be both low viscosity Dispersions of less than 100 mPas (20 ° C) as well as highly viscous Dispersions with more than 10,000 mPas (20 ° C) when stored have good viscosity constancy or to thicken the mach - or in rare cases, e.g. highly concentrated dispersions - also for Decrease in viscosity. As a test method whether the dispersion system has reached a stable rheological state, that is suitable The method according to the invention based on the viscoelastic parameters an assessment of the expected constant viscosity and storage stability of the dispersion. There this procedure for testing the thermodynamic state of Dispersions obviously have general validity, it is more stable in the manufacture aqueous dispersions of cationic fabric softener compounds extremely helpful.

Another object of the invention is therefore the application of the invention Process in the preparation of viscosity-stable, aqueous dispersions of cationic Quaternary ammonium compound type plasticizer compounds at least two groups with 12-22 carbon atoms selected from alkyl, alkenyl, acyloxyalkyl or acylamidoalkyl groups.

The following examples are intended to illustrate the subject matter of the invention explain:

Examples 1.1 recipe

Stepantex VS 90 (90% by weight in isopropanol) 19.11% by weight MgCl ₂ .6 H ₂ O (10% by weight in H ₂ O) 1.50% by weight NaOH (10% by weight in H ₂ O) 0.04% by weight Colorant Sicomet Azorubin 85 E 122 (1% by weight in H ₂ O) 0.03% by weight Perfume oil 0.80% by weight water 78.52% by weight

1.2 Manufacturing process A

The water was heated to 50 ° C. The Stepantex VS 90 was heated to 60 ° C and dispersed into the water with stirring. After stirring for 10 minutes, the MgCl ₂ solution was added; after stirring for a further 5 minutes, the pH was adjusted to pH = 3 by adding NaOH. The dye was then added, the mixture was stirred for a further 10 minutes, then cooled from 50 ° C. to 20 ° C., perfume oil was added and the mixture was stirred for a further 10 minutes. Stirring was carried out using an IKA-VISK measuring stirrer with an inclined blade stirrer (conveying downwards) (d = 10 cm, immersion depth 7.3 cm). The mixing vessel has 12.4 cm inside height, 12 cm top diameter and 7.5 cm bottom diameter.

1.3 Manufacturing process B

100 g of the dispersion prepared in 1.2, 10 minutes with an Ultraturrax homogenizer in a 150 ml beaker (IKA, T 25 with 8000 U / min ^-1 idle speed) homogenized.

2.1 recipe

Stepantex VS 90 (90% by weight in isopropanol) 22.22% by weight MgCl ₂ .6 H ₂ O (10% by weight in H ₂ O) 4.71% by weight Dye Sicomet Azornbin 85 E 122 (1% by weight in H ₂ O) 0.05% by weight Perfume oil 0.71% by weight water 72.31% by weight

2.2 Manufacturing process C

The water was heated to 50 ° C., the Stepantex X 8211 was heated to 60 ° C. and dispersed into the water with stirring. After 10 minutes of stirring, the MgCl ₂ solution was added, after a further 5 minutes of stirring, the dye was metered in, stirred for a further 10 minutes, then cooled from 50 ° C. to 35 ° C. and the perfume oil was added and the mixture was stirred for a further 10 minutes, at 35 ° C cooled to room temperature (20 ° C) and stirred for 10 minutes (IKA stirrer).

3. Measurement of the rheological properties

It became a shear rate controlled rheometer Rheometrics RFS II with cone-plate measuring system and a shear stress controlled Rotation rheometer Carri-Med CS with cone and plate system used.

Results

Manufacturing process A B C. immediately after manufacture y (20 ° C) [mPas] 100 3050 50 after 25 days storage at 7 ° C G' 91 292 2.3 G'' 34 103 3.3 tan δ 0.4 0.4 1.5 y (20 ° C) 330 2920 50 stability unstable stable stable

In Fig. 1 are the values for lg y and lg tan δ entered in the coordinate system in which the area according to the invention given by equation I (according to lg y = - 2.9 * lg tan δ + (2.3 ± 0.3 ) is drawn. It can be seen that the dispersion A is outside the viscosity-stable range according to the invention.

Claims (2)

1. A process for testing the stability and viscosity constancy of dispersions of cationic fabric softener compounds belonging to the group of quaternary ammonium compounds containing at least 12 to 22 C atoms selected from alkyl, alkenyl, acyloxyalkyl or acylamidoalkyl groups, characterized in that the viscoelastic parameters G'' (loss modulus) and G' (storage modulus) are determined and, using the relation corresponding to formula I: lg y = - k · lg tan δ + A where tan δ is the ratio of G'' to G' and k and A are system constants which are determined by preparing various constant-viscosity dispersions of the particular cationic fabric softener compound and reading off the slope k and the ordinate section A of the resulting straight line from the graphic plotting of lg y against lg tan δ,
   the viscosity y is calculated and the measured viscosity is tested for accordance with the calculated viscosity.
2. The application of the process claimed in claim 1 in the production of viscosity-stable aqueous dispersions of cationic fabric softener compounds belonging to the group of quaternary ammonium compounds containing at least 12 to 22 C atoms selected from alkyl, alkenyl, acyloxyalkyl or acylamidoalkyl groups.

Images