EP0997522A1 - Light duty liquid cleaning composition - Google Patents

Abstract

Light-duty liquid detergent composition contains anionic surfactants (I) and fatty acid alkyl ester alkoxylates (II). Light-duty liquid detergent composition contains anionic surfactants (I) and fatty acid alkyl ester alkoxylates of formula R<1>-COO(AO)m-R<2> (II): R<1> = 5-22C (preferably 7-17C) alkyl or alkenyl; R<2> = 1-6C alkyl, preferably Me or Et; AO = a 2-4C alkylene oxide unit; m = 1-20, preferably 5-12.

Description

The invention relates to "light duty liquid" (LDL) cleaning agents, in particular Containing hand dishwashing detergents and household cleaning agents Fatty acid alkyl ester alkoxylates as particularly skin-friendly, environmentally compatible Surfactant with a very good washability and good solubility behavior.

High demands are placed on modern household cleaning agents and dishwashing detergents: they must have good cleaning properties against dirt and grease, but also be environmentally friendly.
Increasing skin intolerance and allergic reactions require the development of new surfactants / surfactant mixtures and / or the use of alternative substances, especially for cleaning agents that are used daily and come into contact with the skin.
In order to minimize transport, storage and packaging costs and to improve handling for the consumer, modern cleaning and dishwashing detergents with high concentrations of detergent substances are commercially available. However, highly concentrated preparations require the use of solvents and / or hydrotropes, which bring the different constituents into solution, bring about a clear and homogeneous formulation with suitable viscosities and at the same time should avoid gel formation during the preparation or storage of the agents. Non-surface-active organic solvents, such as ethanol, glycol, polyglycols or solubilizers, for example alkylbenzenesulfonates with short chain lengths, such as, for example, toluene or xylene sulfonate, are usually used for this. It is desirable to be able to dispense with those compounds which have little or no washing activity.

It has now been found that the use of fatty acid alkyl ester alkoxylates in light duty liquid formulations make it possible to use organic solvents such as ethanol or to dispense with glycols and hydrotropes or to significantly reduce them and nevertheless to achieve a favorable viscosity setting (100 cps to 1000 cps). The risk of gel formation during long-term storage due to slow evaporation of the Solution broker does not exist here. At the same time, the use of Fatty acid alkyl ester alkoxylates in LDL formulations are good skin-friendliness with good washing ability.

The invention relates to light duty liquid cleaning agents, in particular liquid hand dishwashing detergents and household cleaning agents, containing anionic surfactants and fatty acid alkyl ester alkoxylates of the formula 1 R ¹ -COO (AO) _m -R ² wherein R ^{1 is} a branched or straight-chain alkyl or alkenyl group with 5 to 22, preferably 7 to 17 carbon atoms, R ^{2 is} a straight-chain or branched alkyl chain with 1 to 6 C atoms, preferably 1 or 2 C atoms, AO for a C ₂ -C ₄ alkylene oxide unit and m is a number from 1 to 20, preferably 4 to 12, in particular 5 to 10.

These fatty acid alkyl ester oxyalkylates are prepared by processes known per se, namely either by oxalkylation of fatty acid alkyl esters in the presence of a suitable catalyst or catalyst system such as, for example, potassium hydroxide or sodium methylate, or by esterification of oxyalkylated alcohols with fatty acids in the presence of an acidic catalyst such as sulfuric acid, p-toluenesulfonic acid, alkanesulfonic acids, Alkylarylsulfonic acid, ZnCl ₂ , phosphoric acid.

Preferably those compounds of formula 1 are used which are narrow Have a range of the degree of polyalkoxylation (so-called "narrow range" oxalkylates), in particular those narrow-range oxyalkylates of the formula 1 which are less than 14% by weight of compounds containing not more than (a - 3) -AO groups and less than 16% by weight of compounds containing not among (a + 3) -AO groups, where a is the number of -AO groups with the designated maximum frequency. This definition is intended for a compound of the formula with the maximum frequency of the -AO groups of 10 (a = 10) are explained in more detail. In this case, the amount of alkoxylated analogous compounds containing 7 and less than 7 -AO groups (a - 3), less than 14 wt .-%. Conversely, the amount of alkoxylated Compounds with a degree of alkoxylation of 13 or more than 13 less than 16% by weight.

Such narrow-range fatty acid alkyl ester oxyalkylates are obtained when one carries out the oxyalkylation reaction in the presence of the following catalysts:

Alkaline earth metal salts of monoesters from dicarboxylic acids and alkoxylated alcohols according to EP-A-337 239. The non-esterified carboxyl group is completely converted into the form of the alkaline earth metal salt.
Partially neutralized Ca salts of succinic acid half-esters substituted with C ₈ -C ₃₀ -alkyl radicals (EP-A-657 410); Alkali and alkaline earth metal compounds from the group of hydroxides, oxides and alcoholates (EP-A-0 335 295); Ca / Al-containing or Ca / Ti-containing catalyst system (US-A-5 220 046).

Particularly suitable alkoxylation catalysts are partially neutralized Alkaline earth metal salts of dicarboxylic acid half esters as described in DE 198 07 991.5.

These fatty acid alkyl ester alkoxylates can be used as nonionic surfactants in the agents according to the invention alone or in a mixture with other nonionic Surfactants, for example with alkyl and / or alkenyl oligoglycosides, Fatty alcohol polyglycol ethers, alkylphenol polyglycol ethers, fatty acid polyglycol esters, Fatty acid amide polyglycol ethers, fatty amine polyglycol ethers, alkoxylated triglycerides, Fatty acid glucamides, poly oil fatty acid esters, sugar esters, sorbitan esters and Polysorbates and / or alkoxylated fatty alcohols are used. The share of nonionic surfactants in total on the total amount of all surfactants in the LDL cleaning agents according to the invention are generally 1 to 50% by weight, the proportion of fatty acid alkyl ester oxyalkylates in the total amount of nonionic Surfactants is approximately 75 to 100% by weight.

In addition to the nonionic surfactants described above, the LDL formulations according to the invention also contain anionic surfactants in amounts of approximately 50 to 99% by weight, based on the total amount of all surfactants. Preferred anionic surfactants are C ₈ -C ₂₀ fatty acid alpha-methyl ester sulfonates, alkyl ether sulfates and sec. Alkanesulfonates.

The alkyl ether sulfates used in the agents according to the invention are water-soluble salts or acids of the formula RO (A) _m SO ₃ M, in which R is an unsubstituted C ₁₀ -C ₂₄ -alkyl or C ₁₀ -C ₂₄ -hydroxyalkyl radical, preferably a C ₁₂ -C ₂₀ alkyl or C ₁₂ -C ₂₀ hydroxyalkyl radical, particularly preferably C ₁₂ -C ₁₈ alkyl or C ₁₂ -C ₁₈ hydroxyalkyl radical. "A" is an ethoxy or propoxy unit, m is a number greater than 0, preferably between 0.5 and approximately 6, particularly preferably between approximately 0.5 and approximately 3, and M is a hydrogen atom or a cation such as, for example a metal cation (e.g. sodium, potassium, lithium, calcium, magnesium, etc.), ammonium or a substituted ammonium cation. Specific examples of substituted ammonium cations are methyl, dimethyl, trimethylammonium and quaternary ammonium cations such as tetramethylammonium and dimethylpiperidinium cations as well as those derived from alkylamines such as ethylamine, diethylamine, triethylamine. Examples of these alkyl ether sulfates are C ₁₂ -C ₁₈ alkyl polyethoxylate (1.0) sulfate, (C ₁₂ -C ₁₈ E (1.0) M), C ₁₂ -C ₁₈ alkyl polyethoxylate (2, 25) sulfate (C ₁₂ -C ₁₈ E (2.25) M), C ₁₂ -C ₁₈ alkyl polyethoxylate (3.0) sulfate (C ₁₂ -C ₁₈ E (3.0) M), C ₁₂ -C ₁₈ alkyl polyethoxylate (4.0) sulfate (C ₁₂ -C ₁₈ E (4.0) M).

In the secondary alkanesulfonates, the alkyl group can either be saturated or unsaturated, branched or linear and optionally with a hydroxyl group be substituted. The sulfo group is statistically distributed over the entire C chain, with the primary methyl groups at the beginning and end of the chain none Possess sulfonate groups. The preferred secondary alkanesulfonates contain linear alkyl chains with 9 to 25 carbon atoms, preferably from 10 to 20 Carbon atoms and particularly preferably 13 to 17 carbon atoms. The cation is sodium, potassium, ammonium, mono-, di- or triethanolammonium, calcium or magnesium and mixtures thereof. Sodium as a cation is simplicity preferred for the sake of it.

In addition to these or instead of these preferred anionic surfactants, the LDL formulations according to the invention also other types of anionic Contain surfactants within the limits specified above, such as Alkyl sulfates, sulfonates, carboxylates, phosphates and mixtures of the mentioned connections. Suitable cations are e.g. Sodium, potassium, calcium or magnesium, as well as ammonium, substituted ammonium compounds, including mono-, di- or triethanolammonium cations, as well as mixtures of these cations. The anionic surfactants suitable for the present invention have surfactant properties and are water-soluble or in water dispersible.

Alkyl sulfates here are water-soluble salts or acids of the formula ROSO ₃ M, in which R is preferably a C ₁₀ -C ₂₄ hydrocarbon radical, preferably an alkyl or hydroxyalkyl radical with C ₁₀ -C ₂₀ alkyl components, particularly preferably a C ₁₂ -C ₁₈ alkyl radical or hydroxyalkyl radical. M is hydrogen or a cation, for example sodium, potassium, lithium or ammonium or substituted ammonium, for example methyl, dimethyl and trimethylammonium cations and quaternary ammonium cations such as tetramethylammonium and dimethylpiperidinium cations and quaternary ammonium cations, derived from alkylamines such as ethylamine, diethylamine, triethylamine and Mixtures of these.

Another suitable anionic surfactant is alkylbenzenesulfonate. The alkyl group can be either saturated or unsaturated, branched or linear and optionally be substituted with a hydroxyl group.

The preferred alkylbenzenesulfonates contain linear alkyl chains with 9 to 25 Carbon atoms, preferably from 10 to 13 carbon atoms, which is cation Sodium, potassium, ammonium, mono-, di- or triethanolammonium, calcium or Magnesium and mixtures thereof.

Other suitable anionic surfactants are carboxylates, for example fatty acid soaps and comparable surfactants. The soaps can be saturated or unsaturated and can contain various substituents, such as hydroxyl groups or alpha sulfonate groups. Linear saturated or unsaturated hydrocarbon residues are preferred as the hydrophobic component in the soaps. The hydrophobic components usually contain 6 to 30 carbon atoms, preferably 10 to 18 carbon atoms.
Other anionic surfactants are salts of acylaminocarboxylic acids, which are formed by reacting fatty acid chlorides with sodium sarcosinate in an alkaline medium (acylsarcosinates), and fatty acid-protein condensation products, which are obtained by reacting fatty acid chlorides with oligopeptides. The salts of alkylsulfamidocarboxylic acids and the salts of alkyl and alkylaryl ether carboxylic acids also have surfactant properties.

Other anionic surfactants which are useful for use in detergents and cleaning agents are C ₈ -C ₂₄ -olefin sulfonates, sulfonated polycarboxylic acids, prepared by sulfonating the pyrolysis products of alkaline earth metal citrates, as described, for example, in GB 1 082 179, alkyl glycerol sulfates, fatty acyl glycerol sulfates, oleyl glycerol sulfates , alkylphenol ether sulfates, primary paraffinsulfonates, alkyl phosphates, alkyl ether phosphates, isethionates such as the acyl isethionates, N-acyl taurides, alkyl succinamates, sulfosuccinates, monoester of sulfosuccinates (especially saturated and unsaturated C ₁₂ -C ₁₈ monoesters) and diesters of sulfosuccinates (especially saturated and unsaturated C ₁₂ -C ₁₈ diesters), acyl sarcosinates, sulfates of alkyl polysaccharides such as sulfates of alkyl glycosides, branched primary alkyl sulfates and alkyl polyethoxy carboxylates such as those of the formula RO (CH ₂ CH ₂ ) _k CH ₂ COO-M + where R is a C ₈ -C ₂₂ alkyl, k is a number from 0 to 10 and M is a soluble salt-forming catio n is. Resin acids or hydrogenated resin acids such as rosin or hydrogenated rosin or tall oil resins and tall oil resin acids can also be used. Further examples are described in "Surface Active Agents and Detergents" (Vol. I and II, Schwartz, Perry and Berch). A large number of such surfactants are also described in US 3,929,678.

Typical examples of anionic surfactants are also alkyl ether sulfonates, Glycerol ether sulfonates, sulfo fatty acids, fatty alcohol ether sulfates, Glycerol ether sulfates, hydroxy mixed ether sulfate, fatty acid amide (ether) sulfates, mono- and Dialkyl sulfosuccinates, mono- and dialkyl sulfosuccinamates, sulfotriglycerides, Amide soaps, alkyl oligoglucoside sulfates, alkyl amino sugar sulfates and alkyl (ether) phosphates. If the anionic surfactants contain polyglycol ether chains, you can use a conventional or narrow homolog distribution exhibit.

Furthermore, foam-reinforcing co-surfactants can be used in the agents according to the invention from the group alkyl betaines, alkyl amido betaines, aminopropionates, Aminoglycinates, imidazolinium betaines and sulfobetaines, amine oxides and Fatty acid alkanolamides or polyhydroxyamides in the weight amounts 1 to 18% be used.

In a preferred embodiment, in addition to the fatty acid alkyl ester ethoxylates and optionally other nonionic surfactants, sec. C ₈ -C ₂₁ -, in particular C ₁₂ -C ₁₈ alkane sulfonate, for example the product available under the trade name Hostapur® SAS (Clariant GmbH), optionally in a mixture with C ₁₂ -C ₁₄ alkyl triglycol ether sulfate, Na salt (Genapol® ZRO , Clariant GmbH) and cocoamidopropylbetaine (Genagen® CAB, Clariant GmbH) are used in the LDL formulations according to the invention.

The total amount of all surfactants (nonionic and anionic) is in generally 15 to 70, preferably 15 to 55 wt .-%, based on the Total weight of the LDL formulations.

Depending on the intended use, the formulations according to the invention contain in addition to the surfactants mentioned, the specific and customary auxiliaries and Additives, for example builders, salts, solubilizers, enzymes, Thickeners, preservatives, fragrances and dyes, pearlescent agents, Emulsifiers and sequestering agents.

Neutral or are suitable as organic and inorganic builders especially alkaline salts that precipitate or complex calcium ions can bind. Suitable and in particular ecologically harmless Builder substances, such as finely crystalline, synthetic water-containing zeolites of the type NaA, which has a calcium binding capacity in the range of 100 to 200 mg CaO / g have a preferred use. Zeolite and the layered silicates can be contained in an amount up to 20 wt .-% in the average. Usable organic builders are, for example, the preferred ones in the form of their Sodium salts used percarboxylic acids such as citric acid and nitriloacetate (NTA), ethylenediaminetetraacetic acid, provided that such use from ecological Reasons is not objectionable. Analogously, polymers can also be used Carboxylates and their salts are used. These include, for example Salts of homopolymeric or copolymeric polyacrylates, polymethylacrylates and in particular copolymers of acrylic acid with maleic acid, and also Polyvinyl pyrrolidone and urethanes. The relative molecular weight of the homopolymers is generally between 1000 and 100,000, that of the copolymers between 2000 and 200,000, preferably 50,000 to 120,000, based on the free acid, In particular, water-soluble polyacrylates are also suitable, for example with about 1% of a sugar polyallyl ether are cross-linked and the one is relative Have a molecular mass above one million. Examples of this are those under Names Carbopol® 940 and 941 available polymers. The cross-linked Polyacrylates are used in amounts not exceeding 1% by weight, preferably in amounts of 0.2 to 0.7 wt .-% used. These builders can be used in amounts up to 5 wt .-% are used.

The desired viscosity of the agent can be added by adding water and / or organic solvents or by adding a combination of organic Solvents and thickeners can be adjusted.

In principle, all mono- or polyvalent come as organic solvents Alcohols into consideration. Alcohols with 1 to 4 carbon atoms, such as Methanol, ethanol, propanol, isopropanol, straight-chain and branched butanol, Glycerin and mixtures of the alcohols mentioned. Further preferred alcohols are polyethylene glycols with a molecular weight below 2000. In particular, the use of polyethylene glycol with a relative Molecular mass between 200 and 600 and in amounts up to 45 wt .-% and from Polyethylene glycol with a molecular weight between 400 and 600 in Amounts of 5 to 25% by weight are preferred. An advantageous mix of Solvents consist of monomeric alcohol, such as ethanol and Polyethylene glycol in a ratio of 0.5: 1 to 1.2: 1.

Other suitable solvents are, for example, triacetin (glycerol triacetate) and 1-methoxy-2-propanol.

Hardened castor oil, salts of long chain fatty acids, preferably in amounts of 0 to 5 wt .-% and in particular in amounts of 0.5 to 2% by weight, for example Sodium, potassium, aluminum, magnesium and titanium stearates or the sodium and / or potassium salts of behenic acid, and polysaccharides, in particular Xanthan gum, guar guar, agar agar, alginates and tyloses, Carboxymethyl cellulose and hydroxyethyl cellulose, also higher molecular weight Polyethylene glycol monoesters and diesters of fatty acids, polyacrylates, polyvinyl alcohol and polyvinylpyrrolidone and electrolytes such as table salt and ammonium chloride.

Enzymes come from the class of proteases, lipases, amylases or their mixture in question. Their proportion can be 0.2 to 1% by weight. The enzymes can be adsorbed on carrier substances and / or in coating substances be embedded.

Suitable preservatives are, for example, phenoxyethanol, Formaldehyde solution, pentanediol or sorbic acid.

Examples of pearlescent agents are glycol distearic acid esters such as Ethylene glycol distearate, but also fatty acid monoglycol esters into consideration.

Sodium sulfate, sodium carbonate, for example, come as salts or adjusting agents or sodium silicate (water glass).

Typical examples of other additives are sodium borate, starch, Sucrose, polydextrose, RAED, stilbene compounds, methyl cellulose, Toluene sulfonate, cumene sulfonate, soaps and silicones.

The products according to the invention are characterized by very good storage stability and good skin-friendliness with high cleanability.

The following examples are intended to explain the invention in more detail without referring to it restrict.

Examples

All percentages are percentages by weight.

example 1 Hand dishwashing liquid

Composition: A Genapol ZRO 4.90% C ₁₂ -C ₁₄ + 7.5 EO MEE 6.00% Hostapur SAS 60 14.70% Genagen CAB 2.40% B E-water ad 100% C. Acticide SPX- (L) 0.20% by weight

The percentages by weight are based on 100% detergent substance

Example 2 Hand dishwashing liquid, concentrate

Composition: A Genapol LRO 20.4% C ₁₂ -C ₁₄ + 7.5 EO MEE 10.2% C ₁₀ -C ₁₄ LAS 12.3% Genagen CAB 3.0% Alkanolamide 1.7% Ethanol 8.5% B water ad 100% C. Acticide SPX- (L) 0.20% by weight

The percentages by weight are based on 100% detergent substance

Example 3 Hand dishwashing liquid

A Hostapur SAS 60 20.50% Genapol LRO 4.00% Genagen LAB 0.50% C ₈ -C ₁₈ + 8 EO MEE 6.00% B water ad 100% C. Acticide SPX- (L) 0.20% by weight

The percentages by weight are based on 100% detergent substance

Example 4 Highly concentrated LDL cleaning agent

A Hostapur SAS 60 33.0% Genapol LRO liquid 30.0% Fatty alkanolamide 2.0% C ₈ -C ₁₈ + 8 EO MEE 6.6% NaCl 0.5% Na ₂ SO ₄ 1.5% Toluene sulfonate, Na salt 0.5% B water C. Acticide SPX- (L) 0.20% by weight

Manufacturing:

All components of A were stirred into B in succession. In conclusion by Addition of C preserved.

Example 5 Delicate detergent for hand washing

A Genapol DU 80 6.0% Fatty acid mixture 5.0% (Prifac 7949: palm kernel / oleic acid potassium hydroxide (w = 85%) 0.8% Triethanolamine 0.69% The percentages by weight are based on 100% detergent substance. B Water (approx. 50 ° C) C. Hostapur SAS 60 5.10% Tri-sodium citrate-2 hydrate 5.00% D Ethanol 2.00% Citric acid 1 hydrate 0.20% C ₈ -C ₁₈ + 7.5 EO NRMEE 6.00% E Acticide SPX- (L) 0.20%

Manufacturing

Components of A were mixed, B added and dissolved well. After that the components of C were stirred in and cooled to room temperature. Components of D were added sequentially, finally by adding preserved by E.

Chemical description of the commercial products used

Hostapur®SAS 60: secondary sodium alkane sulfonate (approx. 60% WAS) Genapol® LRO: C ₁₂ -C ₁₄ sodium alkyl diglycol ether sulfate (approx. 30% WAS) Genagen®LAB: C ₁₂ -C ₁₄ alkyl dimethyl betaine (approx. 30% WAS) Genagen® CAB: Cocoamidopropyl betaine Genapol DU 080: C ₁₁ oxo alcohol polyglycol ether with 8 ethylene oxide Genapol ZRO C ₁₂ -C ₁₄ sodium alkyl triglycol ether sulfate (approx. 30% WAS) C ₁₂ -C ₁₄ + 7.5 EO MEE C ₁₂ -C ₁₄ fatty acid methyl ester ethoxylate (7.5 EO) C ₈ -C ₁₈ + 8 EO MEE C ₈ -C ₁₈ fatty acid methyl ester ethoxylate (8 EO) C ₈ -C ₁₈ + 7.5 EO MEE C ₈ -C ₁₈ fatty acid methyl ester ethoxylate (7.5 EO) C ₈ -C ₁₈ + 7.5 EO NRMEE C ₈ -C ₁₈ fatty acid methyl ester ethoxylate (7.5 EO) narrow range product C ₁₀ -C ₁₄ LAS Linear C ₁₀ -C ₁₄ alkyl benzene sulfonate, Na salt

The above products are commercial products from Clariant GmbH
Alkanolamide coconut fatty acid diethanolamide
Acticide® SPX- (L) preservative
Commercial product from Thor Chemie GmbH, Speyer

Application results

The cleaning ability of the dishwashing detergent was based on the so-called "Mini-plate" test, the skin-friendliness of the agent according to the invention "Zein test" determined and compared with reference formulations 1 and 2.

Reference formulation 1

Composition: A Genapol ZRO 7.00% by weight Hostapur SAS 60 21.00% by weight B E-water ad 100% by weight

Reference formulation 2

Mini-Plate Test: Prüfung der schaumstabilisierenden Eigenschaften von Spülmitteln

Prinzip:
Durch Einbringen von mit Fett und Stärke (je 4,125 Gew.-% Butter, Creme fraiche, Margarine, Olivenöl, Palmin, Rindertalg, Schweineschmalz, Sonnenblumenöl, 17 Gew.-% Roggenvollkornmehl, 5 Gew.-% Milchpulver, 45 Gew.-% Wasser, Farbmittel) beschmutzten Mini-Plates wird der vorher durch ein Umwälzgerät erzeugte Schaum (Uhrglas) einer Spüllösung zerstört.

Composition: A Genapol LRO 21.8% C ₁₀ -C ₁₄ LAS 13.2% Alkanolamide 1.7% Ethanol 8.5% B E-water ad 100% Mini plate and zein test results formulation Mini plate Viscosity mPas (according to Brookfield) Zein test / mg N / 100 ml example 1 16 300 161 Reference 1 16 390 263 Example 2 31 292 179 Reference 2 34 gel 203

Mini-plate test: testing the foam-stabilizing properties of detergents

Principle:
By adding fat and starch (4.125% by weight butter, creme fraiche, margarine, olive oil, palmin, beef tallow, lard, sunflower oil, 17% by weight wholegrain rye flour, 5% by weight milk powder, 45% by weight Water, colorant) soiled mini plates, the foam (watch glass) of a rinsing solution previously generated by a circulating device is destroyed.

To carry out the mini-plate test, weigh 1.50 g of the soiling described above on each watch glass and spread it on the watch glass using a spoon and a glass rod. 15 to 20 o'clock glasses are prepared in this way. The soiling is dried at room temperature for 30 minutes.
2.00 g of product (with a WAS content of less than 25%) or 1.00 g of product (with a WAS content of more than 25%) are placed in a 3 liter crystallizing dish and 2500 ml about 50 ° C. hot drinking water. This solution is transferred to a 5 l plastic bowl into which the circulator is already immersed, taking care that the detergent has dissolved well. After switching on the heating plate, the initial temperature (target: 47 +/- 2 ° C) is determined and foam is generated for 1 minute using a stirrer-driven circulator with a speed of 300 rpm. Then remove the dirt from a watch glass with the washing-up brush for 20 to 25 seconds while the circulator is running.

Then the rollers and the bottom of the bowl with the washing brush 35 to For 45 seconds with the recorder still switched on Free dirt. This process (rinsing one watch glass and cleaning each Rolls and bowl) is repeated until the foam disintegrates and is short-term shutdown of the circulator no coherent Foam blanket forms more.

The number of cleaned mini-plates is proportional to the amount of inserted Fat and starch and is given as a measure of the washing performance of the washing liquor.

Determination of the zein value principle

The solubility of zein, a protein from the coating substance of the corn kernel, in Surfactant solutions represent a measure of the skin tolerance of surfactants Zeintest is a relationship between the amount of zein dissolved Surfactant solutions and the assets of these surfactant solutions, the ultimate To loosen epidermal layers. The determination of the dissolved by the surfactant The amount of zein is determined by determining the nitrogen contained in the zein according to Kjeldahl. The higher the nitrogen value, the higher the proportion of the dissolved Zeins and the worse the skin tolerance.

Claims (6)

Light duty liquid detergent containing anionic surfactants and fatty acid alkyl ester alkoxylates of formula 1 R ¹ -COO (AO) _m -R ² wherein R ^{1 is} a branched or straight-chain alkyl or alkenyl group with 5 to 22, preferably 7 to 17 carbon atoms, R ^{2 is} a straight-chain or branched alkyl chain with 1 to 6 C atoms, preferably 1 or 2 C atoms, AO for a C ₂ -C ₄ alkylene oxide unit and m is a number from 1 to 20, preferably 4 to 12, in particular 5 to 10. Light duty liquid cleaning agent according to claim 1, characterized in that they contain compounds of formula 1 that have a narrow range of Have degrees of polyoxyalkylation. Light duty liquid cleaning agent according to claim 1, characterized in that, in addition to the compounds of formula 1, they contain further nonionic surfactants contain. Light duty liquid cleaning agent according to claim 1, characterized in that it contains C ₈ -C ₂₀ fatty acid alpha-methyl ester sulfonates, alkyl ether sulfonates or sec. Contain alkanesulfonates as anionic surfactants. Light duty liquid cleaning agent according to claim 1, characterized in that the total amount of surfactants from 1 to 50 wt .-% of nonionic and 50th up to 99 wt .-% of anionic surfactants. Light duty liquid cleaning agent according to claim 1, characterized in that they have a total of 15 to 70 wt .-% of surfactants, based on the total weight of the detergent.