WO1991009929A1 - Stabilizers for aqueous cleaning fluids - Google Patents

Abstract

Disclosed are mixtures consisting of a propane diol, an alkoxypropane diol with 1-4 carbon atoms in the alkoxy residue and, optionally, ethanol. These mixtures are suitable for use as stabilizers for aqueous cleaning fluids and improve, in particular, the enzyme stability of the products.

Description

 Stabilizers for aqueous liquids

The invention relates to stabilizers for aqueous liquid detergents consisting of a propanediol, an alkoxypropanediol having 1 to 4 carbon atoms in the alkoxy radical and optionally ethanol, their use in aqueous liquid detergents and aqueous liquid detergents with improved enzyme stability, which these mixtures contain.

Aqueous liquid detergents have become increasingly important in recent years because they are easier to dose than powder products and have a higher dissolving speed in the wash liquor. They usually contain anionic and non-ionic surfactants, soaps, enzymes and complexing agents.

However, the production of aqueous liquid detergents is associated with two problems:

As a result of the high surfactant concentration and the high electrolyte content, the surfactant components show a considerable tendency to salt out and form multiphase systems, which is undesirable from an application and aesthetic point of view and

- Depending on the temperature, pH value and surfactant composition, the rapid deactivation of the enzyme component and thus the decrease in washing power are observed, in particular against protein-containing soiling, such as e.g. Blood, egg yellow or milk [G. acobi, A.Löhr, "Detergents in Textile Washing", Verlag Chemie, Weinheim, 1987, pp. 87f.]

These problems are usually countered by the use of hydrotropic stabilizers or stabilizer mixtures based on ethanol or propylene glycol, such as are used e.g. are described in the patent publications US 3806 136 and FR 13 97 399. From the patent application DE 18 08 834 AI aqueous enzyme preparations are also known, which are stabilized by adding short-chain alcohols or alkylene glycol ethers. However, since short-chain alcohols increase the flammability of the products and the addition of alkylene glycol ethers undesirably lowers the viscosity of the liquid detergent and can also lead to odor problems, the use of such substances as stabilizers is not yet a satisfactory solution.

The technical problem to be solved was therefore to develop stabilizers for aqueous liquid detergents which are free from the disadvantages described.

The invention relates to stabilizers for aqueous liquid detergents consisting of a geraisch from a propanediol, an alkoxypropanediol with 1 to 4 carbon atoms in the alkoxy radical and optionally ethanol.

These mixtures have solubilizing properties and reduce the tendency of anionic surfactants to crystallize. Surprisingly, however, it was found that the stability of detergent enzymes in aqueous solutions is also significantly improved. Examples of propanediols are Propand ^'iol-1.2 and preferred wise called 1,3-propanediol. Mixtures of the two substances can also be used in any ratio.

Typical examples of alkoxypropanediols are 2-methoxypropanediol-1,3,1-ethoxypropanediol-2,3,2-ethoxypropanediol-1,3,1-n-propoxypropanediol-2,3,2-n-propoxypropanediol-1 , 3, 1-i-propoxypropanediol-2,3, 2-i-propoxypropanediol-1,3, l-butoxypropanediol-2,3, 2-n-butoxypropanediol-1,3, l-tert-butoxypropanediol-2 , 3 or 2-tert-butoxypropanediol-1,3. However, the stabilizers preferably contain l-methoxypropanediol-2,3.

The invention further relates to the use of the above-mentioned stabilizers consisting of mixtures of a propanediol, an alkoxypropanediol having 1 to 4 carbon atoms in the alkoxy radical and optionally ethanol for stabilizing aqueous liquid detergents.

The stabilizers can each contain 1 to 80, preferably 20 to 60% by weight of a propanediol, 1 to 80, preferably 20 to 60% by weight of an alkoxypropanediol and 0 to 60% by weight of ethanol. However, mixtures which are composed of 50% by weight of a propanediol and 50% by weight of an alkoxypropanediol have high enzyme stabilization and particularly good solubilizing properties. Mixtures consisting of 50% by weight of 1,3-propanediol and 50% by weight of 2,3-methoxypropanediol are flame retardant, have an advantageous consistency in aqueous liquid detergents and are odorless. For the reasons mentioned, their use is therefore particularly preferred. Finally, the invention relates to aqueous liquid detergents with improved enzyme stability, containing detergent enzymes, anionic and nonionic surfactants and as enzyme stabilizers, mixtures consisting of a propanediol, an alkoxypropanediol with 1 to 4 carbon atoms in the alkoxy radical and optionally ethanol.

Aqueous liquid detergents with particularly high enzyme stability contain, as enzyme stabilizers, mixtures consisting of 1 to 80, preferably 20 to 60% by weight of a propanediol and 1 to 80, preferably 20 to 60% by weight of an alkoxypropanediol and 0 to 60% by weight of ethanol . Again, particular preference is given to aqueous liquid detergents which contain, as enzyme stabilizers, mixtures consisting of 50% by weight of 1,3-propanediol and 50% by weight of 2,3-methoxypropanediol.

The detergent enzymes which are stabilized according to the invention in aqueous solution can be amylases, lipases, but in particular proteases. Among the proteases, alkalases, esperases, subtilopeptidases, savinases, optimases and maxatases are preferably stabilized, which are generally derived from fungi and bacteria, e.g. B. Bacillus subtilis or Bacillus licheniformis [Labor 2000, 16 (1985/86)]. Proteases of this type are particularly suitable for breaking down protein soiling and are therefore widely used in detergents [Soap.Cosm.Chem.Spec, 48 (1983)].

Proteases catalyze the hydrolysis of the peptide bonds of proteins, polypeptides and related compounds. In this way, free amino and carboxyl functions are obtained and the long-chain protein structures are broken down into shorter chains, which can be easily removed from the fibers with the aid of surfactants. Since the proteases mentioned develop their catalytic properties in particular in the alkaline range, it is advisable to adjust the pH of the liquid detergent to 6.5 to 10, preferably 7 to 8.5.

Typically, the aqueous liquid detergents according to the invention contain 0.3 to 1.0, preferably 0.5 to 0.8% by weight of detergent enzymes.

Anionic and nonionic surfactants can be contained in the liquid detergent as detergent components. Examples of suitable anionic and nonionic surfactants for use in the invention include:

- Alkylbenzenesulfonates, available e.g. B. by the action of gaseous sulfur trioxide on alkylbenzenes of the general formula (I),

(I) R ¹ - »]

in which R ^{1 represents} an alkyl radical having 12 to 18 carbon atoms and B represents a phenyl radical,

Fatty alcohol polyglycol ethers of the general formula (II),

in which R ^{2 represents} a linear or branched alkyl or alkenyl radical having 12 to 22 carbon atoms and 0, 1, 2 or 3 Double bonds, n stands for 2 or 3 and m stands for numbers from 1 to 20,

Alkyl (ether) sulfates, available e.g. B. by the action of gaseous sulfur trioxide on fatty or oxo alcohols and their ethylene oxide addition products of the general formula (II),

Sulfofatty acid methyl ester, available e.g. B. by the action of gaseous sulfur trioxide on fatty acid methyl ester of the general formula (III),

(III) R3C0-0CH ₃

in which R ^ CO represents a saturated or unsaturated fatty acyl radical having 12 to 18 carbon atoms and 0, 1, 2 or 3 double bonds,

Sulfofatty acids, available e.g. B. by the action of gaseous sulfur trioxide on fatty acids of the general formula (IV),

(IV) R ^ COOH

in which R ^ CO represents a saturated or unsaturated fatty acyl radical having 12 to 22 carbon atoms and 0, 1, 2 or 3 double bonds and

Alkyl oligoglycosides of the general formula (V),

(V) R ⁵ -0- (G) _p in the R ⁵ for an alkyl or alkenyl radical having 8 to 22, preferably 10 to 16 carbon atoms, G for a glycose unit which is derived from a sugar with 5 to 6 carbon atoms, in particular glucose, and p for is a number between 1 and 10, preferably between 1.1 and 3.0.

The use of alkylbenzenesulfonates and fatty alcohol polyglycol ethers is particularly preferred.

The ratio between anionic and nonionic surfactants among one another can be 10:90 to 90:10% by weight. However, aqueous liquid detergents with a particularly high washing capacity contain a nonionic proportion of the surfactant component of at least 55% by weight.

The proportion of anionic and nonionic surfactants in the composition of aqueous liquid detergents can total 10 to 40% by weight. However, products with satisfactory washing performance preferably contain at least 20% by weight of surfactant.

In the context of the invention, aqueous liquid detergents can also contain 0 to 20, preferably 5 to 16,% by weight of soaps of the general formula (VI),

(VI) R6-C00X

in which R ⁶ C0 is a saturated or unsaturated fatty acyl radical having 12 to 18 carbon atoms and 0, 1, 2 or 3 double bonds and X is an alkali or alkaline earth metal, preferably sodium. Furthermore, the aqueous liquid detergents according to the invention can be used in minor amounts of complexing agents, e.g. B. citric acid, ethylenediaminetetraacetic acid, nitrilotriacetic acid or phosphonic acids, alkali metal hydroxide for pH adjustment, triethanolamine as a detergency booster and suitable preservatives, such as p-hydroxybenzoic acid.

The following examples are intended to explain the subject matter of the invention in more detail.

Examples

Example 1:

Enzyme activity. The influence of mixtures consisting of propanediol-1,3 and l-methoxypropanediol-2,3 on the enzyme stability of Alkalase 2.5 L with 1.2% Ca was investigated by the EPE-valine-p-nitrophenyl ester method [ J.Biol.Chem. , 244, 5745 (1969); Biochem.Biophys. Res. Comm., 41, 464 (1970)]. The concentration of the protease in water (15 ° d) was 0.52% by weight, that of the solvent 5.0% by weight. The solution was incubated at 60 ° C. in a water bath. The activity immediately after preparation of the test solution was determined photometrically against Maxatase ^R ) as the standard and set to 100%; all information on residual activity after storage refers to this. The results are summarized in Tab. 1:

Tab. 1: Enzyme activity

E.g. stabilizer residual activity [% -rel.] Immediately 20 min 40 min 60 min

1 l-methoxy ρropanediol-2,3 / 100 71 53 44 propanediol-1,3 (1: 1)

I without stabilizer 100 48 30 20 Examples of use:

Tab. 2: Recipes:

2) Ci3 / i5-0xoalkohol-7E0, Lutensol ^) A 07, from BASF

3) Phosphonic acid, Turpinal ^R ) D2, from Henkel

4) Measurement at 20 ° C, specification in mP / s Example 2:

Tab. 3: Washing performance on a blood-milk-soot soiling.

III 64.4 45.0 25.5

Example 3:

Tab. 4: Washing performance on a soot of milk and soot

III 70.1 45.0 35.8 Test soiling:

A) Blood-milk-soot soiling on cotton 11 fabric

B) Milk soot soiling on cotton 11 fabric

Washing conditions:

Launderometer test method

Liquor 250 ml

Fleet loading 1 part by weight of fabric: 30 parts by weight of water

Dosage 9.0 g / 1 recipe

Water hardness 16 ° d

Temperature 40 ° C

Determination Average of 3 determinations

The washing capacity was checked immediately after the test batches had been prepared and after storage for d = 28 days at 40 ° C.

The washed tissue was lightened using test stains A and B by photometric remission measurement compared to a barium sulfate standard, the remission of which was set at 100%. The indication is in% remission (% -R.) The decrease in washing power after 28 days of storage was determined in comparison to the "immediately" value, the remission of which was set at 100%.

Claims

Claims 1. Use of mixtures consisting of a propanediol, an alkoxypropanediol with 1 to 4 carbon atoms in the alkoxy radical and optionally ethanol as stabilizers for aqueous liquid detergents. 2. Use of mixtures according to claim 1, characterized gekennzeich¬ net that it from 1 to 80 wt .-% 1,3-propanediol, 1 to 80 wt .-% l-2,3-methoxypropanediol and 0 to 60 wt. -% ethanol exists. 3. Stabilizers for aqueous liquid detergents consisting of a mixture of a propanediol, an alkoxypropanediol with 1 to 4 carbon atoms in the alkoxy radical and optionally ethanol. 4. stabilizers for aqueous liquid detergents according to claim 3, characterized in that they are mixtures consisting of 1 to 80 wt .-% 1,3-propanediol, 1 to 80 wt .-% 1-methoxypropanediol-2,3 and 0 to 60 wt .-% ethanol is. 5. Aqueous liquid detergent with improved enzyme stability containing detergent enzymes, anionic and nonionic surfactants, characterized in that mixtures consisting of a propanediol, an alkoxypropane diol with 1 to 4 carbon atoms in the alkoxy radical and, if appropriate, ethanol are present as enzyme stabilizers. 6. Aqueous liquid detergent according to claim 5, characterized in that mixtures consisting of 1 up to 80% by weight of 1,3-propanediol, 1 to 80% by weight of 2,3-1-methoxypropanediol and 0 to 60% by weight of ethanol are contained. 7. Aqueous liquid detergent according to claims 5 and 6, characterized in that proteases are contained as detergent enzymes. 8. Aqueous liquid detergent according to one of claims 5 to 7, characterized in that proteases from the group of the alkalases, subtilopeptidases, esperases, savinases, optimases or maxatases are contained as detergent enzymes. 9. Aqueous liquid detergent according to one of claims 5 to 8, characterized in that 5 to 10 wt .-% of a soap of the general formula (VI) are contained, (VI) RO-COOX in which R ^ CO represents a saturated or unsaturated fatty acyl radical having 12 to 18 carbon atoms and 0, 1, 2 or 3 double bonds and X represents an alkali or alkaline earth metal. 10. Aqueous liquid detergent according to one of claims 5 to 9, characterized in that the pH is 6.5 to 10.