EP0490040B1 - Liquid detergent - Google Patents

Abstract

Liquid detergents consist nowadays in the surfactant component mainly of petrochemical-based surfactants; the biodegradability and the ecotoxicity usually do not correspond to those of surfactants based on natural raw materials. A mixture is therefore proposed for liquid detergents, which contains a very high proportion of surfactants from renewable raw materials; the washing results and biodegradability are outstanding. The mixtures according to the invention consist of fatty alcohol ethoxylate, soap and anionic surfactant, plus alkyl polyglycoside.

Description

The present invention relates to liquid preparations for washing textiles. Liquid detergents today mainly consist of anionic surfactants, especially alkylbenzenesulfonate, fatty alcohol oxyethylate and soap. These surfactants, which are common in detergent formulations, are mainly based on petrochemicals. In view of the future raw material situation (oil shortage), this petrochemical basis is a considerable disadvantage. Another disadvantage is that the biodegradability and ecotoxicity of these surfactants often do not reach the corresponding level of surfactants on a native basis.

The object of the invention was therefore to find a surfactant mixture for liquid detergents which contains a high proportion of surfactants which are obtained from renewable raw materials; In addition to excellent washing results, high biodegradability was required.

This object was achieved by a mixture which, in addition to fatty alcohol oxyethylate and soap and small amounts of anionic surfactant, contains> 3 to 30% alkyl polyglycoside.

• 0 - 7 Gew.-% Aniontensid,
• 11 - 30 Gew.-% Fettalkoholoxethylat und
• > 8 - 30 Gew.-% Seife.

The invention therefore relates to a liquid detergent containing> 3 to 30% by weight of alkyl polyglycoside of the formula I.

RON _n I,

in which R represents a linear or branched, saturated or unsaturated aliphatic alkyl radical with 8 to 18 carbon atoms or mixtures thereof and Z _{n stands} for a polyglycosyl radical with n = 1.0 to 1.4 hexose or pentose units or mixtures thereof,

• 0 - 7% by weight anionic surfactant,
• 11-30% by weight of fatty alcohol oxyethylate and
• > 8 - 30 wt% soap.

EP-0 075 994, EP-0 075 995 and EP-0 075 996 claim surfactant mixtures which contain anionic and non-ionic surfactants in addition to alkyl polyglycoside, although the degree of glycosidation of the alkyl polyglycoside is ≥ 1.5. DE-37 02 286 claims alkyl polyglycosides in addition to anionic and nonionic surfactants as detergents with the restrictions that the anionic content should be <50% of that of the oxyethylate. EP-0 199 765 describes alkyl polyglycoside mixtures with anionic and nonionic surfactants, the content of nonionic surfactants should be ≤ 10% and the degree of glycosidation of the alkyl polyglycoside is 1,4 1.4. The brochure "Henkel APG, Alkylpolyglycoside" (1990) recommends formulations for liquid detergents which, according to EP-0 199 765, contain contents of Ox 10% for oxyethylates, whereas the content of alkylbenzenesulfonate is 13% by weight.

It has now surprisingly been found that the formulation according to the invention delivers excellent washing results with an extremely low anionic surfactant content.

Alkyl polyglycosides

Alkyl polyglycosides used according to the invention satisfy the formula I

RON _n I

in which R represents a linear or branched, saturated or unsaturated aliphatic alkyl radical having 8 to 18 carbon atoms or mixtures thereof and Z _{n represents} a polyglycosyl radical with n = 1.0 to 1.4 hexose or pentose units or mixtures thereof.

Alkyl polyglycosides with alkyl radicals with 9 to 16 carbon atoms and a polyglycosyl radical with n = 1.1 to 1.4 are preferred. Alkyl polyglucosides are particularly preferred.
The alkyl polyglycosides used according to the invention can be produced by known processes based on renewable raw materials.

For example, dextrose is reacted with n-butanol to give butylpolyglycoside mixtures in the presence of an acidic catalyst, which are transglycosidated with long-chain alcohols, likewise in the presence of an acidic catalyst, to give the desired alkylpolyglycoside mixtures. Or dextrose is immediately reacted with the desired long-chain alcohol.

The structure of the products can be varied within certain limits. The alkyl radical R is determined by the choice of the long-chain alcohol. Favorable for economic reasons are the industrially accessible alcohols with 8 to 18 carbon atoms, in particular native alcohols from the hydrogenation of carboxylic acids or carboxylic acid derivatives. Ziegler alcohols or oxo alcohols can also be used.

The polyglycosyl radicals Z _n are determined on the one hand by the selection of the carbohydrate and on the other hand by setting the average degree of polymerization n z. B. according to DE-OS 19 43 689. In principle, it is known that polysaccharides, e.g. B. starch, maltodextrins, dextrose, galactose, mannose, xylose etc. can be used. The industrially available carbohydrates starch, maltodextrins and especially dextrose are preferred. Since the economically interesting alkyl polyglycoside syntheses are not regio- and stereoselective, the alkyl polyglycosides are always mixtures of oligomers, which in turn represent mixtures of different isomeric forms. They exist side by side with α- and β-glycosidic bonds in pyranose and furanose form. The linkages between two saccharide residues are also different.

Alkyl polyglycosides used according to the invention can also be prepared by mixing alkyl polyglycosides with alkyl monoglycosides. The latter can e.g. B. according to EP-A 0 092 355 using polar solvents such as acetone from alkyl polyglycosides.

The degree of glycosidation is expediently determined by means of ¹ H-NMR.

The detergents according to the invention contain> 3 to 30% alkyl polyglycoside, preferably 5-20%.

Compared to almost all other surfactants used in detergents, the alkyl polyglycosides are considered to be extremely environmentally compatible. The degree of biodegradation for the alkyl polyglycosides according to the invention, determined by means of a sewage plant simulation model / DOC analysis, is 96 ± 3%. This number can be seen against the background that with this test method (total degradation) a degree of degradation ≥ 70% already indicates that the substance is readily degradable.

The acute oral toxicity LD 50 (rat) with> 10,000 mg / kg as well as the aquatic toxicity LC 50 (gold orfe) with approx. 12 mg / l and EC 50 (daphnia) with 30 mg / l are by a factor of 3 to 5 cheaper than the corresponding values of today's most important surfactants. The same applies to skin and mucous membrane compatibility.

Anionic surfactants

Alkylbenzene sulfonates, alkane sulfonates, olefin sulfonates, fatty alcohol sulfates and fatty alcohol ether sulfates having 9 to 18 carbon atoms in the alkyl or alkylene group are used as anionic surfactants. Na, K, NH ₄ , Mg and mixtures are the counterions. These anionic surfactants, which can be present in the mixtures according to the invention in amounts of 0 to 7% by weight, are not understood to mean soap. Quantities of 0 to 5% by weight are preferred.

Fatty alcohol oxyethylates

The fatty alcohol oxyethylates used according to the invention correspond to compounds of the formula II

R "-O- (CH ₂ -CH ₂ -O) _x H II,

in which R "denotes a linear or branched, saturated or unsaturated alkyl radical having 8 to 22, preferably 10 to 20 carbon atoms and x 2 to 20, preferably 3 to 15.

The compounds are generally prepared by addition of ethylene oxide onto longer-chain alcohols in the presence of basic or acidic catalysts. For economic reasons, commercially available alcohols with 8 to 22 carbon atoms from the hydrogenation of carboxylic acids or carboxylic acid derivatives are favorable. Ziegler alcohols or oxo alcohols can also be used.

The alcohol oxyethylates are known to be readily biodegradable; Their data regarding aquatoxicity, skin and mucous membrane compatibility are also favorable.

The liquid detergents according to the invention contain 11 to 30% fatty alcohol oxyethylates, which can also be mixtures. Contents of 12 to 25% by weight are preferred.

Soap

Fatty acid salts or their acids according to the invention correspond to formula III

R "'COOP III,

in which R "'denotes a saturated or unsaturated alkyl radical having 8 to 22 carbon atoms and P being hydrogen, alkali, ammonium or alkanolammonium.

The detergents according to the invention contain> 8 to 30% soap, which will usually be a mixture of different components. Contents of> 8 to 25% are preferred.

Other non-surfactant components

First of all, builders should be mentioned as non-surfactant components. According to the invention, water-soluble builders such as different polyphosphates, phosphonates, carbonates, polycarboxylates, citrates, polyacetates such as NTA and EDTA, etc. or mixtures thereof are used. These compounds are usually used as alkali salts, preferably as sodium salts. Although not complex sodium sulfate is also to be mentioned here. The use of water-insoluble builders, such as aluminosilicates of suitable particle size, is also according to the invention (cf. EP-A 0 075 994). The concentration of the builders in the detergent is 0 to 70%, preferably 0 to 50%.

Bleaching agents such as sodium perborate, optionally combined with bleach activators such as tetraacetylethylene diamine etc. or percarbonate, are also used according to the invention; Other bleaching agents are of course also possible (cf. K. Engel, Tenside Surfactants 25, S. (1988). The concentration of the bleaching agents is 0 to 40%, preferably 0-30%.

Adjusting agents such as low molecular weight mono- or dihydric alcohols, alkyl ethers of polyhydric alcohols, hydrotropics such as alkylbenzenesulfonates with 1 to 3 carbon atoms in the alkyl radical, alkanolamines or urea, enzymes such as in particular proteases and enzyme stabilizers, corrosion inhibitors such as alkali silicates, optical, may be used according to the invention Brighteners, especially those based on stilbene and pyrazoline, foam regulators, graying inhibitors such as e.g. B. carboxymethyl cellulose, perfume oils, dyes and other ingredients customary for liquid or powder detergents.

The total use concentration in the liquid detergents according to the invention is 0.3-20 g / l for the surfactant fraction according to the invention. 0.5-10 g / l are preferred.

Examples

The invention is illustrated by the following examples. The liquid detergent formulations listed in Table 1 each contain 6% triethanolamine, 12% ethanol, 6% 1,2-propylene glycol and water ad 100% in addition to the surfactant components mentioned according to the invention.

The clear point and the viscosity were determined to characterize the cleaning liquid.

To determine the clear point, 10 g of cleaning liquid were cooled to -20 ° C. in a Shukoff flask and then heated. The temperature is measured with complete clarification.

The viscosity of the cleaning liquid was measured in a rotary viscometer (Haake RV 20) at 25 ° C under shear rates of approx. 10 sec. ^-1 .

The washability was determined in a normal household machine, and the foam development was also checked here.

11 x 18 cm rags made of WFK test fabric with skin fat pigment soiling served as model fabric: polyester (PE), mixed fabric (MG) and cotton (BW), which are sewn onto cotton towels. At the same time, the washing machine is loaded with 4 kg of ballast fabric. Drinking water (13 ° dH) serves as water, the active ingredient concentration is 5 g / l, the pH value is 8, the liquor ratio is 1: 4 and the washing time is about 80 minutes. The washing values after drying the fabrics were - as usual - measured spectrophotometrically relative to a white standard (Datacolor, 560 nm).

The table shows the comparison of the properties of the detergents according to the invention as a liquid formulation with those of other known combinations and with a liquid brand detergent, in which one can presuppose an optimization of the formulation. The clear point, viscosity and foaming capacity correspond approximately to the standard customary for liquid detergents.

In comparison with the branded detergent (Example 9 (V) and even with the alkylpolyglycoside-containing formulations (Examples 1 (V) to 3 (V)), the detergents according to the invention behave clearly superior in their washing activity. The results at low temperatures and problematic fabrics are almost outstanding like PE and MG: The tests show the superiority of the formulations according to the invention over the use of alkypolyglycosides with too high degrees of glycosidation or over too high contents anionic surfactant at the expense of oxethylates.

The following abbreviations were used in the table: C ₁₂ C ₁₄ [G 1.2] - C _12/14 alkyl polyglycoside with a degree of glycosidation of 1.2 C ₁₂ C ₁₄ [G 1.4] - C _12/14 alkyl polyglycoside with a degree of glycosidation of 1.4 C ₁₂ C ₁₄ [G 1.6] - C _12/14 alkyl polyglycoside with a degree of glycosidation of 1.6 MARLIPAL ^(R) 24/60 - C _12/14 alkanol oxyethylate with 6 mol EO / mol MARLON ^(R) A - C ₁₀ C ₁₃ alkyl benzene sulfonate MARLINAT ^(R) DFK 30 - C ₁₂ C ₁₈ alkyl sulfate Soap - coconut fatty acid PE - polyester MG - blended fabrics BW - cotton

Claims (6)

1. A liquid detergent containing > 3 - 30 % by weight of alkyl polyglycoside of the formula I
   
           R-O-Z_n     I
   
   in which R is a linear or branched, saturated or unsaturated aliphatic alkyl radical having 8 to 18 carbon atoms or mixtures thereof and Z_n is a polyglycosyl radical with n = 1.0 to 1.4 hexose or pentose units or mixtures thereof,

   0 - 7 % by weight of anionic surfactant,

   11 - 30 % by weight of fatty alcohol oxethylate and

   > 8 - 30 % by weight of soap.
2. A liquid detergent according to claim 1, characterized in that the anionic surfactant is an alkylbenzenesulphonate, alkanesulphonate, olefinsulphonate, fatty alcohol sulphate and/or fatty alcohol ether sulphate wherein, in each case, the alkyl or alkylene group contains 9 - 18 C atoms, and Na, K, NH₄, Mg and mixtures thereof are the counter-ions.
3. A liquid detergent according to either of claims 1 or 2, characterized in that the fatty alcohol oxethylate corresponds to the formula II $${\text{R"-O-(CH}}_{\text{2}}{\text{-CH}}_{\text{2}}{\text{-O)}}_{\text{x}}\text{H}$$

   

   in which R'' is a linear or branched, saturated or unsaturated alkyl radical having 8 to 22 carbon atoms and x = 2 to 20.
4. A liquid detergent according to any one of claims 1 to 3, characterized in that the soap corresponds to the formula III
   
           R"'COOP     III
   
   in which R"' is a saturated and/or unsaturated alkyl radical having 8 to 22 carbon atoms and P is hydrogen, alkali metal, ammonium or alkanolammonium.
5. A liquid detergent according to any of claims 1 to 4, characterized in that builders, bleaches, fillers, enzymes, stabilizers, antiredeposition agents, corrosion inhibitors, optical brighteners, dyes, perfume oils and optionally other additives are present as non-surfactant ingredients.
6. A liquid detergent according to any one of claims 1 to 5, characterized in that the concentration of the surfactant portion used is 0.3 to 20 g/l.