FR2466501A1 - Stable liq. aq. soap compsn. - contg. ethanolamine soap and fatty acid or alkanol:amide as thickener - Google Patents

Abstract

Liq. aq. soap comprises a single liq. phase contg. 5-30% of a soap of mono- and/or di-ethanolamine, and 0.5-5% of a 12-18C fatty acid and/or an alkanolamide of a 12-18C fatty acid as thickener. Soaps from 10-18C satd. fatty acids are pref. partic. 10-14C fatty acids from coconut oil or palm oil. A small amt., not more than 30(10-20)wr.% of soaps from tallow (16-18C) may be included. The compsn. esp. contains 10-25% of the soap. A small amt., not more than 2%, of a Na soap may be included. The pref. amide thickener is a diethanolamide of coconut fatty acids. The amt. of thickener is esp. 1-4(2)wt.%. The soap may contain an opacifier, esp. ethylene glycol mono- or di-stearate, e.g. a 20% soln. in Na lauryl ether sulphate; Zn stearate is an alternative opacifier. The soap may be used for washing one's hands, as a gel for use under a shower, or for washing textiles. A stable compsn. with viscosity more than 2000 cP or even up to 10,000 cP can be obtd.

Description

 The present invention relates to a liquid soap composition and more particularly to compositions in which the soap component comprises soap other than sodium.

 Aqueous liquid soaps containing sodium soap as the main soap ingredient tend to be unstable and easily form heterogeneous gels even at low soap contents not exceeding 5% by weight. It is for this reason that more soluble soaps, especially those based on potassium, ammonium and triethanolamine are generally used in the manufacture of liquid soaps based on water.

When thickening aqueous liquid soaps, it is not possible to use sodium chloride as traditionally used in the thickening of liquid detergents other than soaps, because soaps tend to precipitate.

 Alternatively, aqueous liquid soaps can be thickened by increasing the concentration of more soluble soaps, or by adding fatty acid ethanolamines or free fatty acids, but these thickening techniques are not without problems, because in presence of certain perfumes as commonly used in the manufacture of soaps, phase separation may occur, in particular when the viscosity exceeds 2000 cPo.

 It has now been discovered that thickened aqueous liquid soaps having a viscosity greater than 2000 cPo, and even as high as 10,000 cPo, can be obtained, without the problem of phase separation mentioned above, by the choice of a special soap for the composition.

The invention therefore relates to an aqueous liquid soap composition comprising a single liquid phase containing a soap chosen from monoethanolamine soaps, diethanolamine soaps and their mixtures and a thickening agent chosen from fatty acids from C12 to C18, alkanolamides of fatty acids from C12 to C18 and mixtures thereof.

 The invention also relates to a process for preparing an aqueous liquid soap composition comprising a single liquid phase, characterized in that a soap chosen from monoethanolamine soaps, diethanolamine soaps and their mixtures and a selected thickening agent are mixed together among the fatty acids from C12 to C18, the alkanolamides of fatty acids from C12 to C18 and their mixtures.

 It should be explained that the liquid soap compositions according to the invention comprise fluid liquids and gels comprising a single liquid phase which is preferably clear like water.

 The soap component of the composition is a water-soluble or water-dispersible soap chosen from monoethanolamine soaps and / or diethanolamine soaps from fatty acids.

The fatty acid portion of monoethanolamine and / or diethanolamine soaps will normally be derived from a mixture of fatty acids having a carbon chain of 10 to 18 carbon atoms. Preferably, these fatty acids include saturated fatty acids.

The preferred soap is a soap of coconut fatty acids, that is to say fatty acids derived from oils of the coconut class, for example coconut oils, palm kernels and Babassu. Fairly low proportions of up to 30%, preferably 10 to 20%, of tallow fatty acid soaps derived from tallow can be mixed with coconut fatty acid soaps to improve their foaming power and their solubility characteristics, if desired. While tallow fatty acids are mainly C16 to C18 fatty acids, coconut oil fatty acids have a shorter chain length and are mainly C10 to C14 fatty acids.

 The amount of soap used in the composition is between 5 and 30%, preferably between 10 and 25% of the weight of the composition.

 Compositions containing less than 5% soap will likely be incapable of producing sufficient foam and having sufficient detergency in service, while compositions containing more than 30% by weight of soap are likely to have the disadvantage that phase separation may occur during storage, with the result that the aqueous liquid soap will assume a heterogeneous granular appearance.

 It is also possible, optionally, to use a small amount of sodium soap in the composition, as long as the unique liquid phase characteristic of the composition is maintained and no significant precipitation occurs.

 When using sodium soap, it will generally be present in the composition at a concentration of no more than 2%.

The aqueous liquid soap composition also includes a C12 to C18 fatty acid or a C12 to C18 fatty acid alkanolamide or a mixture of such
compounds as a thickening agent, instead of conventional thickeners such as sodium chloride or sodium sulfate which are used in liquid detergents other than soaps. The alkanolamide of fatty acid can also help in the solubilization of the perfume which is commonly used in the composition.

The preferred alkanolamide is the coconut fatty acid diethanolamide and the preferred fatty acid is a fatty acid of the coconut type.

The amount of fatty acid or alkanolamide of fatty acid or of their mixture which can optionally be used is between 0.5 and 5%, preferably between 1 and 4% and is ideally around 2% the weight of the composition.

 If less than 0.5% by weight of the fatty acid and / or the fatty acid alkanolamide is used, it is likely that the composition will be insufficiently thickened.

Furthermore, if more than 5% by weight of fatty acid and / or alkanolamide of fatty acid is used, the composition may be too thick for use in the form of a liquid product. However, this is not necessarily a disadvantage if a gel type product is required. A proportion of more than 5% by weight of the fatty acid alkanolamide can cause phase separation giving an otherwise transparent product an opaque or cloudy appearance due to the separate perfume.

The composition may also optionally comprise other ingredients conventionally used in soaps such as foam reinforcing agents, humectants such as glycerin, humectants, dyes and opacifiers.

 A particularly preferred opacifier which can be used when a solid opaque rather than transparent soap composition is desired is mono- or di-ethylene glycol stearate, for example in the form of a 20% solution in lauryl ether sulfate sodium. Another opacifying agent which can be used is zinc stearate.

 The products according to the invention can be prepared by mixing together the ingredients defined above in the amounts specified here. It is convenient, however, to form the monoethanolamine soap and / or the diethanolamine soap by mixing together mono- and / or diethanolamine with free fatty acids in the appropriate stoichiometric proportions, or with a slight excess of the fatty acids. The excess fatty acids added for this purpose can also serve as a thickening agent as described here.

The product can take the form of a clear liquid soap such as water, that is to say transparent, in which case it will not contain an opacifier, or alternatively it can take the form of an opaque liquid soap containing an opacifier as defined here.

The compositions according to the invention can be used for personal care or for washing fabrics. Examples of personal care detergents are liquid soaps for use in dispensers for hand washing or as liquid or shower gel type products.

 The invention is illustrated by the following examples which present liquid soap products for personal care and for washing fabrics.

Example 1
This example illustrates a product of the shower gel type.

A shower gel type product is prepared by mixing the following ingredients together
% in weight
Monoethanolamine soap from C12 to C18 fatty acids 14.2
C12 to C18 fatty acids 3.0
2.5 coconut fatty acid diethanolamide
Glycerol 0.5
Perfume 1.5
Distilled water 78.3
The shower gel has a pH between 8.5 and 9.0 and a viscosity between 2000 and 6000 cPo.

Example 2
This example illustrates a product of the shower gel type.

You can prepare a shower gel product by mixing the following ingredients together
% in weight
Diethanolamine soap from C12 to C18 fatty acids 16.7
C12 to C18 fatty acids 3.0
Coconut diethanolamide 3.0
Glycerol 0.8
Perfume 1.5
Distilled water 75.0
The shower gel will have a pH between 8 and 9.5 and a viscosity between 2,000 and 7,000 cPo.

Example 3
This example illustrates a liquid product for washing fabrics.

A liquid product for tissue washing can be prepared by mixing together the following ingredients
% 0 by weight
Monoethanolamine soap from C to C to C18 fatty acids 19.8
Potassium soap from C12 to C18 fatty acids 4.2
Coconut fatty acid diethanolamide 3.5
Ethanol 5.0
Perfume 0.5
Brightener and coloring matter 0.9
Water 66.1
The liquid product can be used to wash fabrics, in particular woolen clothes by dilution with water at the rate of 1 part of liquid product for 100 to 500 parts of water.

Example 4
This example illustrates a liquid soap product for personal care.

A liquid soap product for personal care is prepared from the following ingredients
% in weight
Lauric acid 8.5
Myristic acid 3.0
Stearin 3.0
Monoethanolamine 3.7
Chelating agent 0.1
Antioxidant 0.02
Perfume 1,2
2.5 coconut fatty acid diethanolamide
Coloring matter 0.001
Water 77,979
The liquid soap product for personal care is prepared by mixing the free fatty acids and the monoethanolamine together so as to form the corresponding monoethanolamine soap of these fatty acids. We
incorporates the other ingredients by mixing carefully to obtain the finished product which can be used for personal care.

Claims (7)

 1. An aqueous liquid soap composition, characterized in that it comprises a single liquid phase containing from 5 to 30% by weight of a soap chosen from soaps from monoethanolamine, soaps from diethanolamine and their mixtures and from 0, 5 to 5% by weight of a thickening agent chosen from fatty acids from C12 to C18, alkanolamides from fatty acids C12 to C18 and their mixtures.  2. A composition according to claim 1, characterized in that the soap is a monoethanolamine soap of fatty acids from C10 to C18.  3. A composition according to claim 1, characterized in that the soap is a diethanolamine soap of fatty acids from C10 to C18. 4. A composition according to one of claims 2 and 3, characterized in that the fatty acids of C10 to C18 include saturated fatty acids.  5. A composition according to one of the preceding claims, characterized in that the fatty acid alkanolamide is coconut fatty acid diethanolamide. 6. A composition according to one of the preceding claims, characterized in that it is in the form of a shower gel. 7. A process for preparing a composition as defined in one of the preceding claims, characterized in that it comprises the step consisting in mixing together a soap chosen from a monoethanolamine soap, a diethanolamine soap or a mixture such soaps, with a thickening agent chosen from fatty acids from C12 to C18, alkanolamides fatty acids from C12 to C18 and mixtures thereof.