CA2002339A1 - Liquid cleansing agent for hard surfaces - Google Patents

Abstract

Abstract of the Disclosure A liquid cleaning composition having improved cleaning power Eor hard surfaces comprising from 0.02 to 40% by weight of an anionic surfactant mixture of a) sulphated hydroxyalkylpolyethylene- or hydroxyalkylpolypropylene glycol ethers of the following formula R1 CH(OSO3M)-CH(R3)-(OCBR4-CH2)n-OR2, wherein R1 = H or C116 alkyl, R2 = C122 alkyl, R3 = C116 alkyl or preferably H, R4 = -CH3 or preferably H, M = H, ammonium, alkylammonium, alkanolammonium (C14) or a monovalent metal atom, n = 0-20, and b) a dioctylsulphosuccinate in a wei.qht ratio of 1:10 to 10:1, as well as organic or inorganic builders.
Advantageously, the composition contains a solubiliser such as toluene-, xylene- or cumenesulphonate, low molecular alcohol or short-chained fatty alcohol and, particularly, an ether of a C16 polyhydric alcohol in a weight ratio of surfactant to solubiliser of from 1:0 to 1:2, as well as other conventional ingredients such as a dyestuff, perfume, preservative and nonionic surfactant.

Description

33~3!
PATENT
Case D8207 LIQVID CL.EANSING AGENT FOR HARD SURFACES
BACKGROUND OF THE INVENTION

1. Field of the Invention:
Liquid all-purpose cleansing agents for use in the home and in industry have become firmly established in the last decade since they can be used easily and without problems.
Usually, these agents are sold as aqueous concentrates.
They can be applied in diluted or undiluted form to a damp absorbent cloth of any kind or to a sponge, which is then used to wipe the hard surfaces of metal, lacquered wood, plastics, ceramic products such as porcelain, floor and wall -tiles and the like, so as to remove dust, grease and soil marks. It is desirable that such surface treatment should not leave any spots or smears of cleaning agent and should not require any subsequent treatment, for example with a damp cloth moistened with plain water.

2. Discussion of Related Art Numerous cleaning agents of this kind are known from the marketplace and from the literature. Thus, German Patent 23 17 076 describes cleaning liquids prepared from dialkylsulphosuccinate and alkylsulphate or alkyle-thersulphate which have good resistance to foaming.
~uropean Patent 71 411 describes liquid detergent : . ~

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compositions consisting of a mixture of dialkylsulphosuc-cinates with anionic or nonionic surfactants. rrhese mixtures are said to be characterized by good cleaning performance and good foaming properties.
European Patent 112 044 describes liquid detergent compositions obtained from dialkylsulphosuccinates combined with alkylethersulphates which have a special C-chain distribution. The formulations are characterized by improved performance and suitability for blending with further substances.
European Patent 112 045 describes liquid detergent compositions consisting of dialkylsulphosuccinates combined with other surfactants (e.g. alkylbenzenesulphonates, alkanesulphonates or fatty alcohol ether sulphates) and small amounts of Mg2fions. The addition of Mg2' brings about advantages in terms of performance and improves the finished product.
European Patent 112 047 describes liquid detergent compositions consisting of dialkylsulphosuccinates with alkylbenzenesulphonates, alkanesulphonates and fatty alcohol ether sulphates. The ternary combinations are said to be characterized by improved performance and production properties.
U.S. Patent 3,639,291 describes a synergistic surfactant combination of vicinal alkylethersulphates of the formula H(CH2)x~CH CH-(CH2)~

wherein 0 < x < 15, 0 < y < 15 and 13 < x~y < 15 with alkylbenzenesulphonates, particularly for use in rinsing by hand. When y = 0, the C-chain length must be 13 < x < 15. The surfactants which are claimed as preferred in this specification have a C-chain length of not more than 12.
In German Patent 26 51 925, 1-methoxysulphates and the preparation and use thereof in washing and cleaning agents are claimed. They are stated to be characterized by high 33g cleaning performance. Additional surfactants mentioned include, inter alia, anionic surfactants as well as other active ingredients conventionally contained in washing, rinsing and cleaning agents, although there is no evidence of their activity in liquid cleaning agents on hard surfaces.
The as yet unpublished German Patent application 37 23 548.8 describes a process for preparing new sulphated hydroxy mixed ethers and the use thereof as wetting agents and raw materials for washing agents.
It is also known from the patent literature to add various polymers to cleaning agents to increase their cleansing power.
From U.S. Patent 3,406,208, liquid cleaning agents are known which may contain water-soluble high molecular weight substances as dirt carriers. Examples mentioned include water-soluble salts of polyacrylic acid and also water-soluble derivatives of cellulose such as carboxymethylcellulose.
From U.S. Patent 3,591,509, liquid all-purpose cleaners are known which, in addition to water-soluble synthetic surface active substances, organic solvents and possibly water-soluble builders, contain a small amount of a special water-soluble carboxymethylcellulose as well as water.
U.S. Patent 3,970,594 discloses liquid builder cleaning agents for hard surfaces, which contain builders as well as small amounts of surfactants combined with small amounts of a mixture of polyvinylalcohol or polyvinylpyrrolidone and polysaccharide salt, and which are also said to have improved dirt removing qualities.
From German Patent 27 09 690, liquid cleaning agents for hard surfaces are known which may also contain added cleansing action intensifying amounts of water-soluble high molecular weight substances such as polyvinylalcohol, polyvinylpyrrolidone and carboxymethylcellulose.
Finally, German Patent 28 40 463 discloses liquid cleaning agents for hard surfaces which contain added cleansing action intensifying amounts of water-soluble polyethyleneglycols.
Not all the above-mentioned polymeric cleaning action intensifiers fully satisfy the requirements which the consumer nowadays imposes even on a liquid cleaner for hard surfaces, from a strictly ecological point of view. Some of the known polymers also have disadvantages, e.g~
insufficient solubility, excessive viscosity or the formation of a residue, i.e. smears or a film, when an agent is used, if it contains these polymers in the amounts necessary to improve the cleansing action significantly.
The formulations which contain alkylbenzenesulphonate and polymers do, however, have an excellent performance profile which it has not hitherto been possible to achieve with polymer-free formulations based solely on surfactants.
Hydroxy mixed ether sulphates prepared and described as in German Patent 37 23 354.8, when mixed in any proportions with the anionic surfactants normally used in all-purpose cleaners, unexpectedly do not exhibit the cleaning performance expected of good products.
Description of Inventlon Other than in the operating examples, or where otherwise indicated, all numbers expressing quantities of ingredients or reaction conditions used herein are to be understood as modified in all instances by the term "about".
Surprisingly, it has been found that an unpredictable improvement in the cleaning performance of liquid cleaning compositions for hard surfaces is achieved if a mixture of hydroxy mixed ether sulphates and sulphosuccinates is used.
When the optimum mixing ratio is used, the cleaning performance of these mixtures, even with no polymers present, reaches the level of good formulations containing alkylbenzenesulphonate and a polymer component.
The present invention therefore relates to a liquid cleaning composition for hard surfaces based on dilute, preferably aqueous solutions containing anionic 3~

surfactants, organic or inorganic builders, optionally water-soluble solvents or solubilisers and other conventional constituents of such cleaning agents, which is characterized in that it contains as anionic surfactants 0.02 to 40, preferably 0.05 to 15% by weight of a mixture of hydroxy mixed ether sulphates and dialkylsulphosuccinates in a ratio by weight of from 1:10 to 10:1, preferably 4:1 to 1:4.
The afore-mentioned hydroxy mixed ether sulphates comprise sulphated hydroxyalkylpolyethylene- or hydroxyalkyl polypropyleneglycol ethers of general formula I

R1 _ CH - CH - (OCH - CH2)n-OR2 (I) wherein R1 represents hydrogen or a straight-chained alkyl group with 1 to 16, preferably 8 to 12, carbon atoms, R2 represents a straight- or branched -chain saturated alkyl group with 1 to 22, preferably 1 to 16 carbon atoms, R3 preferably represents hydrogen but may also represent a straight-chained alkyl group with 1 to 16 carbon atoms, R4 preferably represents hydrogen but may also represent a methyl group, M represents hydrogen, ammonium, alkylammonium, alkanolammonium, wherein the alkyl and alkanol groups each contain from 1 to 4 carbon atoms, or a monovalent metal atom, and n represents a number in the range from 0 to 20, preferably 0 to 15, and mixtures of several such compounds. They are prepared by reacting epoxides of general formula II
o R1 _ CH - CH - R3 (II) wherein R1 and R3 are defined as hereinbefore, with alkoxy-alkanols of general formula III

%339 H - (OCH - C~12) n ~ oR2 (III) wherein R2, R4 and n are defined as hereinbefore at elevated temperature in the presence of a catalyst to obtain hydroxyalkylpolyethylene- or hydroxyalkylpolypropylene glycol ethers of general formula IV

R1 _ CH - C~ - (OCH - CH2) n ~ oR2 (IV) OH
wherein R1, R2, R3, R4 and n are defined as hereinbefore, or mixtures thereof; reacting the resulting compounds (IV) or mixtures thereof at elevated temperature with a sulphating reagent, introducing the crude sulphation product into an aqueous basic solution and keeping the mixture at elevated temperature; adjusting the mixture to a pH in the neutral or weakly alkaline pH range; and, if desired, isolating the products (I) or mixtures thereof thus obtained from the reaction mixture in a manner known per se.
The dialkylsulphosuccinates are alkali metal, ammonium or substituted ammonium salts and may be derived from a C7, C~ or C9 alcohol, which may be straight-chained or branched, or from any desired mixture thereof. The preferred materials are the straight-chained and branched dioctylsulphosuccinates. The dialkylsulphosuccinates are prepared by conventional methods, e.g. by esterification of maleic acid and subsequent sulphonation with bisulphite.
The anionic surfactants may occur in the form of their alkali metal, alkaline earth metal and ammonium salts and as soluble salts of organic bases such as mono-, di- or triethanolamine. The sodium salts are usually preferred for reasons of cost.
For the liquid cleaning compositions according to the invention, the substances used as builders include inorganic or organic compounds which have an overall alkaline reaction, more particularly inorganic or organic complex forming agents, preferably in the form of the alkali metal or amine salts thereof, particularly the sodium and potassium salts. The alkali metal hydroxides can here also be counted as builders.
Suitable inorganic complex forming builders include in particular the polyphosphates which have an alkaline reaction, especially the tripolyphosphates and pyrophosphates. For reasons of heat of hydration they may be wholly or partially replaced by organic complex forming agents. Other inorganic ~uilders which may be used according to the invention include, for example, bicarbonates, carbonates, borates, silicates or orthophosphates of alkali metals.
The organic complex for~eling agents of the aminopolycarboxylic acid type include, inter alia, nitrilotriacetic acid, ethylenediaminetetraacetic acid, N-hydroxyethyl ethylenediaminetriacetic acid and polyalkylene polyamine-N-polycarboxylic acids. Examples of di- and polyphosphonic acids include:
methylenediphosphonic acid, 1-hydroxyethane-1, 1-diphosphonic acid, propane-l, 2, 3-triphosphonic acid, butane-l, 2, 3, 4 tetraphosphonic acid, polyvinylphosphonic acid, copolymers of vinylphosphonic acid and acrylic acid, ethane-l, 2-dicarboxy-1, 2-diphosphonic acid, ethane-l, 2-dicarboxy-1,2-dihydroxy diphosphonic acid, phosphonosuccinic acid, 1-aminoethane 1, 2-diphosphonic acid, amino-tri (methylenephosphonic acid), methylamino- or ethylamino-di (methylenephosphonic acid) and ethylenediamine-tetra (methylenephosphonic acid) .
As examples of N- or P-free polycarboxylic acids or salts thereof for use as builders, compounds containing carboxyl groups are frequently, although not exclusively, proposed. a large number of these polycarboxylic acids have a complex forming capacity for calcium. They include for example citric acid, tartaric acid, benzene hexacarboxylic acid, tetrahydrofuran tetracarboxylic acid, glutaric acid, succinic acid, adipic acid or mixtures thereof.
Since cleaning compositions for household use are generally adjusted to the neutral to slightly alkaline pH

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range, i.e. aqueous solutions thereof ready for use at concentrations of 2 to 20, preferably 5 to 15, ~/1 of water or aqueous solution have a pH in the range ~rom 7.0 to 10.5, preferably 7.0 to 9.5, it may be necessary to add acidic or alkaline components, possibly as buffers, to regulate the pH value.
Suitable acidic substances include conventional inorganic or organic acids or acid salts such as hydrochloric acid, sulphuric acid, alkali metal bisulphates, aminosulphonic acid, phosphoric acid or other phosphorus acids, particularly the anhydric phosphorus acids or the acid salts ~hereof or the acidically reacting solid compounds thereof with urea or other lower carboxylic acid amides, partial amides of phosphoric acids or anhydric phosphoric acid, lactic acid, polycarboxylic acids such as citric acid, tartaric acid, glutaric acid, succinic acid, adipic acid or mixtures thereof and the like.
If the content of alkaline builder is not sufficient to regulate the pH value, it is also possible to add organic or inorganic compounds with an alkaline activity such as sodium hydroxide, alkanolamines, namely mono-, di- or triethanolamine or ammonia.
In addition, solubilisers known per se may be incorporated either individually or as mixtures with one another, these solubilisers including, in addition to the water soluble organic solvents such as low molecular weight aliphatic alcohols with 1 to ~ carbon atoms, the so-called hydrotropic substances of the lower alkylarylsulphonate type, such as toluene, xylene or cumene sulphonates or short-chained alkylsulphates such as octylsulphate. They may also occur in the form of their sodium, potassium or alkylamino salts. Other solubilisers which may be used are water-soluble organic solvents, particularly those with boiling points above 75, such as the ethers of similar or different polyhydric alcohols or the partial ethers of polyhydric alcohols. These include, for example, di- or triethyleneglycol-polyglycerines as well as the partial 2~%~3~

ethers of ethylenPglycol, propyleneglycol, butyleneglycol or glycerol with aliphatic monohydric alcohols containing 1 to 6 carbon atoms in the molecule.
Examples of suitable organic solvents which are water-soluble or emulsifiable with water also include ketones, such as acetones, methylethylketone as well as aliphatic, cycloaliphatic, aromakic and chlorinated hydrocarbons, and as well the terpene alcohols.
The weight ratio of surfactant to solvent or solubilising agent may be from 1:0 to 1:2, preferably 1:0.05 to 1:1.
In order to regulate the viscosity of the composition it may be advisable to add higher polyglycolethers having a molecular weight of up to 600 or polyglycerol. It is also advisable to add sodium chloride or urea in order to regulate the viscosity.
In addition, the composition may contain other conventional additives such as dyestuffs and perfumes, preservatives and nonionic surfactants known for these compositions.
Experiments In order to demonstrate the advantages of the cleaning compositions according to the invention compared with known cleansers for hard surfaces, experiments were designed to test their cleaning power.
Testing of cleaning action The cleaning power was tested using the method described below, which gives easily reproducible results. The remo~al of dirt from hard surfaces was evaluated pursuant to the cleaning power test described in Seifen-Ole-Fette-Wachse 112, 371 (1986).

The cleaning composition to be tested was applied to an artificially soiled plastics surface. The artificial soil used for the diluted form (0.1% by weight of surfactant) was that referred to as dirt composition No. 2. When a cleaning composition having a surfactant content of 10~ by weight was used, the test dirt used was a mixture of Vaseline~, qlycerol esters of fatty acid and pigments. The test surface of 26 X 28 cm was uniformly coated with 2 g of the artificial soil composition using a wiper blade.
A synthetic sponge was soaked or coated with 10 ml of the cleaning solution and the test surface was also coated or soaked with 10 ml of the cleaning solution being tested, having a surfactant content of 0.1% by weight, and the sponge was moved mechanically over the test surface. With a 10~ by weight surfactant cleaning solution, only the test surface was coated with 10 ml of the cleaning solution.
After 10 wiping movements, the cleaned test surface was held under running water and the loosened dirt was removed.
The cleaning action, i.e. the degree of whiteness of the plastics surface cleaned in this way, was measured with a photoelectric colorimeter LF 90 (Dr. B. Lange). The clean white plastics surface was used as the whiteness standard.
As the clean surface was set as 100% and the dirty surface indicated 0 in the measurements, the values read off for the cleaned plastics surface can be equated with the percentage cleaning power (% CP). In the tests which follow, the values given as "RL rel. [%]" are the values obtained by this method for the cleaniny power of the cleaning composition tested, based on the cleaning power of the comparison composition (RL = 100%). Each value is the average from 3 measurements taken.

Example 1 The following all-purpose cleaner formulations were tested in concentrated form, as is customary wh~n tackling stubborn stains in the home, to determine their cleaning power.
The comparison composition used was a powerful formula containing alkylbenzenesulphonate and polymer having the following formulation, which falls within the scope of German Patent 28 40 463:

339i 8%/wt of C1013 alkylbenzenesulphonate, sodium salt, 2%/wt adducts of 10 mol of ethylene oxide to 1 mol of a mixture of oleyl and cetyl alcohols, 2%/wt sodium gluconate, 0.1%/wt polyethylene glycol having a molecular weight of about 600,000 (commercial product Polyox~ WSR 205 made by Union Carbi~e Corp.), and the remainder/ water.
The pH of the formulation was adjusted to 7.0 using 50%
sodium hydroxide solution.
The cleaning power tRL rel.) of the formulation is gi~en in ~%], based on the cleaning power of the comparison composition as the standard (RL = 100) hereinafter.
The general formula of the hydroxy mixed ether sulphates (HMS) tested here is as follows:
CmH2m~1--CH~CH2~- ( CH2-CH2-O ) x-CnH2n+1 OS03Na The parameters m, x and n thus clearly characterize the HMS .
The dialkylsulphosuccinate used was the sodium salt of diisooctylsulphosuccinate.

Formulations:
Percent by weight Dialkylsulpho- - 2 4 6 8 10 succinate Sodium gluco- 2 2 2 2 2 2 nate Water Remainder--------------------->

HMS RL rel. [%]
n x m _ ~

4 4 10 1 20 ~4 114 111 51 33 4 10 121 35 ~3 137 146 124 46 ~2/14 9 10 1 28 34 131 126 63 34 The tests show that powerful formulations can be produced using synergistic combinations of hydroxy mixed ether sulphates with dialkylsulphosuccinates. The paxameters m, x and n can vary over a wide range.
Example 2 The following all-purpose cleaner formulations were tested ~or their cleaning power at the concentrations normally used in the home (0.1% by weight of surfactant).
For comparison, the formulation containing alkylbenzenesulphonate and polymer described in Example 1 was tested, diluted 1:100 with water.
-Formulations:
Percent by weight HMS 0.1 0.08 0.06 0.04 0.02 Dialkylsulpho- - 0.02 0.04 0.06 0.08 0.1 succinate Sodium glu- 0.02 0.02 0.02 0.02 0.02 0.02 conate Water Remainder----------------------------~

3;3g HMS I RL rel. [%]
---- t n x m ~ 10 12 1 73 78 89110 84 81 . ~ I
The tests show that e~en at this concentration synergistic effects are achieved which result in cleaning power ranging from good to very good. Compositions of this kind can also be prepared in the form of spray cleaners.

Example 3 The following test procedures are intended to show in particular that compositions containing a hydroxy mixed ether sulphate (HMS) characterized by the parameters n = 4, x = 10 and m = 12, over a wide wide of concentrations with various builder components, solvents and solubilisers and mixtures thereof, result in very good cleaning performances. The products were optically transparent (clear) at ambient temperature. When mixtures of solvents and solubilisers are used, e.g. consisting of cumenesulphonate and octylsulphate, or ethanol and octylsulphate, smaller amounts of these components are needed to achie~e clear cleaning solutions than when the individual components are used. The pH of the 10% by weight formulations was 7 in each case.
The abbreviations used for the products in the Table are as follows:
NTA: Nitrilotriacetic acid EDTA: Ethylenediaminetetraacetic acid STP: Sodium tripolyphosphate Sokalan~ DCS: Mixture of glutaric acid, succinic acid and adipic acid made by BASF

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The first line indicates the cleaning performances "RL rel. [%]" at the conce.ntration of use, i.e. 0.1% by weight of surfactant. The cleaning powers RL rel. [%3 when used in concentrated form, i.e. with a 10% by weight surfactant content, are shown in the second line.

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The pH of the lO~ solutions was 7 in each case.
Combinations with the hydroxy mixed ether sulphate, characterized by m = 12, x = 10 and n = 4, and the following co-surfactants are mentioned by way of example:

ABS: C1013 alkylbenzenesulphonate, sodium salt FAS: C1214 alkylsulphate, sodium salt SAS: C1317 alkanesulphonate, sodium salt FES: C12~14 alkylethersulphate, sodium salt with about 2 moles ethylene oxide (E0).

The first line in the following table shows the cleaning performances "RL rel. [%]" at an overall surfactant concentration of 10% by weight. After dilution (1:100~ of the formulations with water, the cleaning power RL rel. [%]
was then determined at the concentration of use, i.e. 0.1%
by weight of surfactant. These results are shown in the second line.

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Claims (12)

1. A liquid cleaning composition for hard surfaces comprising from about 0.02 to about 40% by weight of a mixture of hydroxy mixed ether sulfates and dialkylsulphosuccinate in a weight ratio of from about 1:10 to 10:1, based on the weight of said composition.

2. A composition as in claim 1, wherein said hydroxy mixed ether sulfates comprise sulphated hydroxyalkylpolyethylene- or hydroxyalkylpolypropylene glycol ethers of formula I
(I) wherein R1 represents hydrogen or a straight-chained alkyl group with 1 to 16 carbon atoms, R2 represents a straight-chained or branched-chained saturated alkyl group with 1 to 22 carbon atoms, R3 represents hydrogen or a straight-chained alkyl group with 1 to 16 carbon atoms, R4 represents hydrogen or a methyl group, M represents hydrogen, ammonium, alkylammonium, alkanolammonium, wherein the alkyl and alkanol groups each have 1 to 4 carbon atoms, or a monovalent metal atom, and n represents a number in the range from 0 to 20, and mixtures of such compounds.

3. A composition as in claim 1, wherein said dialkylsulphosuccinate is obtained from a straight-chained or branched C7-C9 alcohol, and is present as the alkali metal, ammonium or substituted ammonium salt.

4. A composition as in claim l, wherein said dialkylsulphosuccinate comprises dioctylsulphosuccinate.

5. A composition as in claim 1, including a solubilizer selected from toluene-, xylene- or cumene-sulphonate, low molecular weight C1-C4 aliphatic alcohol, and short-chained fatty alcohol sulfate.

6. A composition as in claim 5, wherein the weight ratio of surfactant to said solubilizer is from about 1:0 to about 1:2.

7. A composition as in claim 1, including a solubilizer selected from a C1-C6 polyhydric alcohol ether and the partial ether of a C1-C6 polyhydric alcohol.

8. A composition as in claim l, containing a builder selected from an inorganic compound and an organic compound.

9. A composition as in claim 8, wherein said builder comprises an inorganic complex forming agent selected from tripolyphosphate and pyrophosphate.

10. A composition as in claim l, containing a carbonate, bicarbonate, borate, silicate and phosphate of an alkali metal.

11. A composition as in claim 1 having a pH of from about 7.0 to about 10.5.

12. A composition as in claim l containing a coloring agent, perfume, preservative and nonionic surfactant.