EP0500819B1

EP0500819B1 - Liquid dishwashing composition

Info

Publication number: EP0500819B1
Application number: EP91910074A
Authority: EP
Inventors: Jadwiga Palicka
Original assignee: Akzo Nobel Surface Chemistry AB
Current assignee: Nouryon Surface Chemistry AB
Priority date: 1990-09-19
Filing date: 1991-04-09
Publication date: 1996-03-06
Anticipated expiration: 2011-04-09
Also published as: AU7903291A; JPH05502265A; FI922184A7; NO179952C; DE69117726T2; FI922184A0; ATE135038T1; WO1992005236A1; EP0500819A1; ES2084165T3; DE69117726D1; DK0500819T3; FI922184L; NO179952B; NO921960L; NO921960D0; SE9002986D0

Abstract

Liquid dishwashing composition which contains at least one amphoteric surface active compound, at least one anionic tenside and at least one foam boosting amide, amidobetaine or amine oxide. The composition suitably contains a mixture of two amphoteric surface active compounds whereby one contains a carbonyl group and the other does not contain such a group. The amphoteric surface active compounds partly replace anionic tensides and hereby a dishwashing composition is obtained which is mild and satisfactory with regard to environment.

Description

Liquid dishwashing composition

The present invention relates to liquid dishwashing compositions and more particularly to such compositions which contain an anionic tenside, a mixture of amphoteric surface active compounds and at least one foam boosting compound.
The most common commercial liquid dishwashing compositions are primarily intended for hand dishwashing and are as a rule aqueous solutions containing anionic tensides, such as alkyl sulfonates and alkyl ether sulfates, as essential component. These dishwashing agents are entirely satisfactory with regard to cleaning effect, foam forming effect and foam stability. However, the dishwashing compositions based on this type of anionic surface active agents are not satisfactory from an environmental point of view nor with regard to mildness to skin, since they have a certain irritating and allergy causing effect. For environmental reasons it has during the last few years been desired to decrease the total amount of anionic tensides, such as for example paraffin sulfonates, used in different cleaning purposes.
According to the present invention it has been found that anionic tensides in dishwashing compositions to a certain extent can be replaced by a mixture of amphoteric surface active compounds and at least one foam boasting compound which is an amine oxide, an amido betaine or an amide to give a dishwashing composition which is mild and kind to the skin, has a good foam stability and gives a low biological load and is more efficient than a dishwashing composition based solely on anionic tensides.
The present invention thus relates to a dishwashing composition as further defined in the appended claims. Dishwashing compositions according to the present invention are particularly suitable for manual washing, of glass, china, kitchen utensils etc, thanks to their mildness.
The amphoteric surface active compounds present in the dishwashing compositions of the invention can be characterized by the general formula (I)
wherein R is a hydrocarbon group having from 7 to 22 carbon atoms, A is the group (C(O)), n is 0 or 1, R₁ is hydrogen or a lower alkyl group, x is 2 or 3, y is an integer of 0 to 4, Q is the group -R₂COOM wherein R₂ is an alkylene group having from 1 to 6 carbon atoms and M is hydrogen or an ion from the groups alkali metals, alkaline earth metals, ammonium and substituted ammonium and B is hydrogen or a group Q as defined.
Amphoteric compounds encompassed by the above given formula are per se known and used in cleaning compositions and shampoo compositions. They are for example described in the European patent applications 160507, 162600 and 214868. According to the European patent application 160507 a combination of two different amphoteric compounds encompassed by the above given formula is used in mild shampoo compositions.
In the amphoteric surface active compounds of the above given formula which are used in the present dishwashing compositions R is a hydrocarbon group having from 7 to 22 carbon atoms and suitably from 11 to 22 carbon atoms. The hydrocarbon group R can be straight or branched, saturated or unsaturated and optionally contain substituents such as hydroxyl groups. The group R can also contain one or several, up to about 20, ethylene oxide groups. The group R can also be a cycloalkyl-alkyl group, an aralkyl or aralkenyl group where the alkyl or alkenyl group contains at least 6 carbon atoms. R is preferably an alkyl or alkenyl group and it is particularly preferred that R is a hydrocarbon group originating from coco, tallow or oleic fatty acid. R₁ in the given formula is hydrogen or a lower alkyl group, suitably with 1 to 6 carbon atoms and is preferably hydrogen or a methyl group. x is 2 or 3 and y is suitably 2, 3 or 4 and preferably 2 or 3. The group R2 is suitably a methylene or an ethylene group, preferably a methylene group. M is hydrogen or an ion from the groups alkali metals, alkaline earth metals, ammonium or substituted ammonium such as for example mono-, di- or tri-hydroxyethylammonium. M is preferably a sodium ion.
Preferred compounds of the formula (I) have the formula (II):
wherein Q is CH₂-COOM or CH₂CH₂COOM, y is 1, 2 or 3 and wherein M, R, x, A, n and B have the above given meanings.
Mixtures of the amphoteric compounds with different values for y are especially preferred. R in these compounds suitably originates from tallow, oleic or coco fatty acid.
The present dishwashing composition may contain a combination of two amphoteric compounds encompassed by the formulae (I) and (II) whereby one compound contains a carbonyl group (below termed type 1) and the other does not contain such a group (below termed type 2), ie an amphoteric compound wherein n is 1 and, respectively, an amphoteric compound wherein n is 0. The amphoteric compound of type 1 acts primarily as a tenside and suds former and the amphoteric compound of type 2 acts primarily as a detoxifying tenside. Suitable weight ratios between compounds of type 1 and type 2 is within the range of from 1:10 to 10:1 and preferably within the range of from 1:5 to 5:1. For amphoteric compounds of type 1 x in the above given formulae is suitably 2 and the groups B are hydrogen or groups Q. For amphoteric compounds of type 2 x in the above given formulae is suitably 3 and all groups B are groups Q.
According to another embodiment of the present invention the mixture of amphoteric compounds contains a carbonyl group containing compound having the general formula (III)
wherein R, A, y, Q and B have the same meaning as given for compounds of formula (I), whereby, however, one group B is the group -CH₂CHR'OH, wherein R' is H or CH₃, in combination with the amphoteric compound having the formula I or II, in which n is 0. The suitable and preferred definitions for R and for M in the group Q are as given for compounds of formula (I). Most suitable are compounds of formula (III) wherein y is 1 and Q is the group -CH₂COOM. As typical examples can be given compounds of formulae (IIIa) and/or (IIIb)
and/or
Amphoteric compounds of formulae IIIa and IIIb are commercially available as mixtures and usually with a weight ratio of compounds of formula IIIa to compounds of formula IIIb within the range of 1:10 to 10:1. Like the amphoteric compounds of formula I and II which contain a carbonyl group the compounds of formula III, IIIa and IIIb act primarily as tensides and suds formers. Suitable weight ratios between compounds of formula III or IIIa and/or IIIb and amphoteric compounds of formula I or II which do not contain a carbonyl group is within the range of from 1:10 to 10:1 and preferably within the range of from 1:5 to 5:1.
Amphoteric compounds of the above given formulae are commercially available and sold under the trade name Ampholak^(R) by Berol Nobel AB, Sweden.
According to the present invention it has been found that the above amphoteric compounds can partly replace anionic tensides in liquid dishwashing compositions. In order to obtain dishwashing compositions having sufficiently good foam stability the amphoteric compounds are combined with an amide, an amido betaine or an amine oxide having this effect. Amides, amido betaines and amine oxides with this effect for dishwashing agents and other products are per se known and can generally be characterized as amides, amido betaines and amine oxides respectively containing at least one longer hydrophobic hydrocarbon group, ie a fatty acid residue having at least 7 carbon atoms and suitably up to 22 carbon atoms.
As examples of suitable amides can be mentioned ammonium and ethanol amides, such as mono- and diethanol amides of fatty acids containing at least one longer hydrophobic group having at least 7 carbon atoms. The amides can be characterized by the general formula (IV) ${R - CO - N(H)}_{p} {(R}_{1} {OH)}_{2-p}$
wherein R is the longer hydrophobic hydrocarbon group, which suitably is a saturated or unsaturated, straight or branched, aliphatic hydrocarbon group with 7 to 21 carbon atoms and preferably is an alkyl or alkenyl group with from 11 to 17 carbon atoms. R₁ is a methylene or ethylene group and p is 1 or 2. As some specific examples of suitable amides can be mentioned mono- and diethanol amides of natural or synthetic fatty acids having 12 to 18 carbon atoms, for example dodecyl carboxylic acid and coco fatty acid.
The amido betaines which can be used can be characterized bv the general formula (V)
wherein R is the longer hydrophobic hydrocarbon group, which suitably is a saturated or unsaturated, straight or branched, aliphatic hydrocarbon group with 7 to 21 carbon atoms and preferably is an alkyl or alkenyl group with from 11 to 17 carbon atoms, n is 1 or 2 and M is preferably hydrogen or a sodium ion.
The amine oxides which can be used can be characterized by the formula (VI) $R(R₁)₂N→O$
wherein R is the longer hydrophobic hydrocarbon group, suitably a saturated or unsaturated, straight or branched aliphatic hydrocarbon group having at least 8 carbon atoms. R is especially a group having from 8 to 22 carbon atoms, and suitably it is an alkyl group which can be substituted by a hydroxyl group and also contain one or several, up to about 10, alkoxy groups, preferably ethylene oxide groups. The groups R₁ are, independent of each other, lower alkyl or hydroxy alkyl groups with from 1 to 4 carbon atoms. Of the mentioned foam boosting compounds the amine oxides are preferred. In the foam boosting compounds the group R is preferable a coconut alkyl group. The weight ratio of the foam boosting compounds, ie the amide, amidobetaine or amine oxide or mixture of two or more of these, to the amphoteric compound or compounds should suitably be at least 1:10 and the ratio is suitably within the range of from 1:10 to 10:1 and preferably within the range from 1:5 to 5:1.
By using the mixture of amphoteric compounds, as above defined, in combination with a fatty acid amide, an amidobetaine or an amine oxide having foam boosting and foam stabilizing effect anionic tensides, which normally are water soluble salts of organic sulfonated acid or sulfated alcohols, in liquid dishwashing compositions can be replaced to a certain extent and hereby a dishwashing composition is obtained which is advantageous from a biological point of view and advantageous with regard to mildness at use. The improved mildness which is obtained is dependent on an efficient detoxification of anionic tensides through formation of mixed micelles of the anionic surface active compounds and the amphoteric surface active compounds. The very low critical micelle concentration of the specific amphoteric compounds is hereby utilized. The desired effect is thus obtained with very small amounts of amphoteric compound, particularly of those of type 2. Dishwashing compositions according to the present invention have also been found to be as effective as such based on solely anionic tensides and this also with regard to economy.
In the present compositions anionic tensides of the above mentioned types are also present, but in lower amounts than usual. Of the total amount of amphoteric and anionic surface active agents at most 90 per cent by weight are anionic tensides. The amount of anionic tenside is suitably within the range of from 90 to 20 per cent by weight, based on the total amount of amphoteric surface active compounds and anionic surface active compounds, preferably within the range 85 to 60 per cent and most preferably within the range of from 80 to 60 per cent by weight. The anionic tensides are, as indicated above, water soluble salts of organic sulfonated acids or sulfated alcohols, and then particularly alkyl sulfates, alkyl ether sulfates, alkyl sulfonates, alkyl aryl sulfonates, wherein the alkyl group usually contains from 8 to 22 carbon atoms. For anionic tensides containing ether groups these are usually ethylene oxide groups and the compounds normally contain between 1 and 10 such groups per molecule. The cations of these salts are alkali metals, alkaline earth metals, ammonium or amines such as mono-, di- and triethanol amine cations. As some specific examples of anionic tensides can be mentioned sodium lauryl sulfonate, sodium lauryl ether sulfate with two or three ethylene oxide groups, the corresponding ammonium or ethanol amine salts, sodium or other salts of dodecyl benzene sulfonic acid and alkyl benzene sulfonic acid wherein the alkyl group contains an average of from 11 to 13 carbon atoms.
The present dishwashing compositions are liquid and the main component for this is of course preferably water. Water used in liquid dishwashing compositions is often deionized but other types of water can also be used. Other liquid solvents can of course be included, such as for example lower alcohols and glycols and lower alkyl ethers of the glycols. These types of solvents are normally present, if at all present, in minor amounts. As some specific examples can be mentioned ethanol, isopropanol, ethylene glycol etc.. Solvents are sometimes included mainly for preservation. One advantage of the present compositions is, however, that since they contain amphoteric compounds of the type according to formula (I) no solvent is required in order to obtain preservative effect.
The present dishwashing compositions can be prepared in per se conventional manner by simple mixing of the components and they can of course also be used in conventional manner. Normal dosage is about 0.2 g/l dish liquor of a dishwashing composition with a total dry content of from about 10 to about 45 per cent by weight.
The dishwashing compositions can of course also contain other conventionally used additives for improvement of different properties such as thickeners, antibacterial agents, colorants, pigments, perfumes etc.. Other amphoteric compounds can also be present if desired, such as betaines, and also nonionic tensides such as glycosides.

As example of a complete dishwashing composition according to the invention as concerns main components those listed below can be given, wherein the ratios of anionic surface active agents to amphoteric surface active agents and ratios for foam boosting compound are adjusted to fall within the above given limits:

Amphoteric compounds as defined in formulae	1 - 10 % by weight
Anionic tenside	10 - 20 % by weight
Amine oxide, amido-betaine or amide	0.3 - 3 % by weight
Alcohol	0.5 - 2 % by weight
Water	to 100 per cent by weight

The invention is further illustrated in the following examples, which, however, are not intended to limit the same. Parts and per cent relate to parts by weight and per cent by weight respectively, unless otherwise stated.

Example

Dishwashing compositions were prepared from the following components (all amounts given are as 100% active substance):
Composition I: 12 g of linear alkyl benzene sulfonate with C12 to C18 alkyl groups, 7 g of sodium lauryl ether sulfate with 3 ethylene oxide groups, 2 g of C12-C18 alkane sulfonate, 2 g of ethanol and 77 g of water. This composition is a standard dishwashing composition.
Composition II: 1.68 g of sodium lauryl ether sulfate with 3 ethylene oxide groups, 10.8 g of C12-C18 alkane sulfonate, 2.22 g of amphoteric compounds, a 1:1 mixture of amphoteric compounds sold under the trade marks Ampholak ^(R) XCO-30 and Ampholak^(R)7TX, respectively, 1.11 g of alkyl dimethyl amine oxide wherein the alkyl group had 14 carbon atoms and 84.19 g of water. The first mentioned amphoteric compound can chemically be characterized as cocoamphocarboxyglycinate and contains a carbonyl group and comprises a mixture of compounds defined in formulae IIIa and IIIb) and the other one can chemically be described as tallowampho polycarboxyglycinate, corresponds to formulae II and does not contain a carbonyl group.
The two compositions were tested by titration of 2 g/l of the solutions with béchamel sauce. Foam heights were determined and plotted against the amount of béchamel sauce. The areas of the diagrams were integrated and weighed and presented as efficiency versus content of amphoteric compound. The area for composition I, the reference, was set as efficiency 1. The efficiency of composition II according to the invention was set in relation to this and found to be 2.4.

Claims

Liquid dishwashing composition, characterized in that it comprises
a) a mixture of at least one amphoteric compound of formula
wherein R is a hydrocarbon group having from 7 to 22 carbon atoms, A is the group (C(O)) n is 0 or 1, R₁ is hydrogen or a alkyl group having 1-6 carbon atoms, x is 2 or 3, y is an integer of 0 to 4, Q is the group -R₂COOM wherein R₂ is an alkylene group having from 1 to 6 carbon atoms and M is hydrogen or an ion from the groups alkali metals, alkaline earth metals, ammonium and substituted ammonium and B is hydrogen or a groups Q as defined; or of formula
wherein y is 1, 2 or 3, R is a hydrocarbon group having from 7 to 22 carbon atoms, A is the group (C(O)), n is 0 or 1, x is 2 or 3, y is 1, 2 or 3, Q is CH₂-COOM or CH₂CH₂-COOM, M is hydrogen or an ion from the groups alkali metals, alkaline earth metals, ammonium or substituted ammonium and B is hydrogen or a group Q as defined; in which n is 1, and at least one amphoteric compound of formula I or II in which n is 0,
or a mixture of at least one amphoteric compound of formula
wherein R, A, y, Q and B have the same meaning as given for compounds of formula (I), whereby, however, one group B is the group -CH₂CHR'OH, wherein R' is H or CH₃, in
combination with the amphoteric compound having the formula I or II in which n is 0. and at least one amphoteric compound of formula I or II, in which n is 0,
in a weight ratio of from 1:10 to 10:1.

b) a foam boosting compound which is an amide, an amidobetaine or an amine oxide, containing at least one longer hydrophobic hydrocarbon group having 7-22 carbon atoms,

c) an anionic surface active agent,
whereby the ratio of foam boosting compound to amphoteric compounds is within the range of from 1:10 to 10:1 and whereby the amount of anionic surface active agent is within the range of from 20 to 90 per cent by weight based on the total amount of amphoteric and anionic surface active compounds.
Dishwashing composition according to claim 1, characterized in that it contains at least one amphoteric compound of formula
and/or
wherein R, A and M have the same meanings as above defined for amphoteric compounds of formula (I) and (II).
and at least one amphoteric compound of formula I or II, in which n is 0; in a weight ratio of from 1:5 to 5:1.
Dishwashing composition according to any of the preceding claims, characterized in that R in the amphoteric compounds is an alkyl or alkenyl group having from 12 to 22 carbon atoms.
Dishwashing composition according to any of the preceding claims, characterized in that it comprises amphoteric compounds of formula I or II wherein n is 0 and all groups B are groups Q.
Dishwashing composition according to claim 1, characterized in that the foam boosting compound is an amine oxide.
Dishwashing composition according to claim 1, characterized in that the anionic surface active agent is a water soluble salt of an organic sulfonated acid or sulfated alcohol.
Use of a mixture of amphoteric compounds and a foam boosting compound in accordance with claim 1, 2, 3, 4 and 5 in a liquid, dishwashing composition containing an anionic surface active agent for the replacement of a part of the anionic surface active agent, the mixture of amphoteric compounds being used in such an amount that the anionic surface active agent is 20-90% by weight of the total amount of the anionic surface active agent and the mixture of amphoteric compounds.