SOLID CLEANSING COMPOSITION COMPRISING AN ACYL ALKYL ISETHIONATE

Abstract

A solid cleansing composition comprising: (i) at least one acyl alkyl isethionate surfactant of the formula (I): wherein R1 represents an optionally substituted C4-C36 hydrocarbyl group; each of R2, R3, R4 and R5 independently represents hydrogen or a C1-C4 alkyl group and wherein at least one of R2, R3, R4 and R5 is not hydrogen; and M+ represents a cation; (ii) a salt of carbonic acid; and (iii) an organic acid.

Claims

1. A solid cleansing composition comprising: (i) at least one acyl alkyl isethionate surfactant of the formula (I): ##STR00015## wherein R1 represents an optionally substituted C4-C36 hydrocarbyl group; each of R2, R3, R4 and R5 independently represents hydrogen or a C1-C4 alkyl group and wherein at least one of R2, R3, R4 and R5 is not hydrogen; and M+ represents a cation; (ii) a salt of carbonic acid; and (iii) an organic acid.

2. A composition according to claim 1, which is effervescent.

3. A composition according to claim 1 or 2, comprising: (i) from 5 to 50 wt% of the at least one acyl alkyl isethionate surfactant of the formula (I); (ii) from 30 to 60 wt% of the salt of carbonic acid; and (iii) from 20 to 40 wt% of the organic acid.

4. A composition according to any preceding claim, wherein R1 represents a C4-C36 alkyl or C4-C36 alkenyl group, preferably a C8-C18 alkyl or C8-C18 alkenyl group, and mixtures thereof.

5. A composition according to any preceding claim, wherein R2 represents a methyl group and R3, R4 and R5 each represent hydrogen, or R4 represents a methyl group and R2, R3 and R5 each represent hydrogen.

6. A composition according to any of claims 1 to 4, wherein the compound of formula (I) comprises a mixture of isomers including a compound of formula R1COOCH2CHR4SO3-M+ in which R4 represents a C1-C4 alkyl group and a compound of formula R1COOCHR2CH2SO3-M+ in which R2 represents a C1-C4 alkyl group.

7. A composition according to any preceding claim, wherein M+ represents a metal cation or an optionally substituted ammonium cation.

8. A composition according to any preceding claim, wherein the at least one acyl alkyl isethionate surfactant of the formula (I) is selected from one or more of sodium lauroyl methyl isethionate, sodium cocoyl methyl isethionate, sodium oleoyl methyl isethionate, and isomers thereof.

9. A composition according to any preceding claim, wherein the salt of carbonic acid is selected from one or more of sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, ammonium carbonate, and ammonium bicarbonate.

10. A composition according to any preceding claim, wherein the organic acid is selected from one or more of a monocarboxylic acid and a polycarboxylic acid, suitably wherein the organic acid is selected from one or more of lactic acid, succinic acid, fumaric acid, salicylic acid, glycolic acid, ascorbic acid, maleic acid, malic acid, isocitric acid, and citric acid.

11. A composition according to any preceding claim, comprising at least one additional ingredient.

12. A composition according to claim 11, comprising from 0.001 to 25 wt%, preferably from 1 to 15 wt%, of the at least one additional ingredient.

13. A composition according to claim 11 or 12, wherein the at least one additional ingredient is selected from one or more of a cationic surfactant, a non-ionic surfactant, an anionic surfactant, and an amphoteric surfactant.

14. A composition according to any of claims 11 to 13, wherein the at least one additional ingredient is selected from one or more of a vegetable oil, an electrolyte, a fragrance, a pigment/colourant, a filler, a wax, a polyquat, a poloxamer, a polyhydroxy alcohol, a chelant, and an active ingredient.

15. A composition according to any preceding claim, which is substantially anhydrous.

16. A composition according to any preceding claim, which is in a compacted, crystalline or powdered form.

17. A cleansing product comprising a composition according to any preceding claim and packaging.

18. A cleansing product according to claim 17, wherein the packaging is water-soluble.

19. A cleansing product according to claim 17 or 18, wherein the packaging comprises a plurality of separate compartments.

20. A method of cleansing skin and/or hair comprising the steps of: (a) contacting the composition according to any of claims 1 to 16 with water to form a cleansing foam; and (b) contacting the cleansing foam with the skin and/or hair.

21. Use of a composition according to any of claims 1 to 16 for cleansing skin and/or hair.

22. A method of manufacturing a solid cleansing product, the method comprising the steps of: (a) forming an admixture comprising: (i) at least one acyl alkyl isethionate surfactant of the formula (I): ##STR00016## wherein R1 represents an optionally substituted C4-C36 hydrocarbyl group; each of R2, R3, R4 and R5 independently represents a hydrogen atom or a C1-C4 alkyl group and wherein at least one of R2, R3, R4 and R5 is not hydrogen; and M+ represents a cation; (ii) a salt of carbonic acid; and (iii) an organic acid; and (b) enclosing the admixture in packaging.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0177] For a better understanding of the invention, and to show how exemplary embodiments of the same may be carried into effect, reference will be made, by way of example only, to the accompanying diagrammatic Figures, in which FIGS. 1 and 2 show the results of dissolution tests for the compositions prepared as Example 4 and Comparative A in the examples.

EXAMPLES

[0178] The invention will now be described with reference to the following non-limiting examples.

[0179] Surfactant A - Sodium lauroyl methyl isethionate

[0180] This commercially available surfactant was provided as a powder containing 85 to 85 wt% of the active surfactant compound.

[0181] Surfactant B - Sodium lauroyl methyl taurate

[0182] This commercially available surfactant was provided as a powder containing 90 wt% of the active surfactant compound.

[0183] Surfactant C = Sodium lauryl sulfate

[0184] This commercially available surfactant was provided as a powder containing 98 wt% of the active compound.

[0185] Surfactant D = Sodium cocoyl isethionate

[0186] This commercially available surfactant was provided as a powder containing 78-80 wt% of the active surfactant compound.

Example 1

[0187] A solid cleansing composition was prepared comprising the following ingredients, as shown in Table 1:

TABLE-US-00001 Component % w/w Citric Acid 26 Sodium Bicarbonate 52 Surfactant A 12 Surfactant B 9 Coconut Oil 1

[0188] Procedure: [0189] 1. In the main mixing vessel, combine Citric Acid and Sodium Bicarbonate. [0190] 2. In a side vessel, mix Surfactant A, Surfactant B and Coconut oil until uniform and lump free. [0191] 3. Add side phase to the main vessel and mix until uniform. [0192] 4. Scoop one gram of the powdered mixture into pill press. Apply pressure to compress mixture into a pill/pellet

Example 2

[0193] A solid cleansing composition was prepared comprising the following ingredients, as shown in Table 2:

TABLE-US-00002 Component % w/w Citric Acid 26 Sodium Bicarbonate 52 Surfactant A 18 Surfactant C 3 Coconut Oil 1

[0194] Procedure: [0195] 1. In the main mixing vessel, combine Citric Acid and Sodium Bicarbonate. [0196] 2. In a side vessel, mix Surfactant A, Surfactant C and Coconut oil until uniform and lump free. [0197] 3. Add side phase to the main vessel and mix until uniform. [0198] 4. Scoop one gram of the powdered mixture into pill press. Apply pressure to compress mixture into a pill/pellet.

Example 3

[0199] A solid cleansing composition was prepared comprising the following ingredients, as shown in Table 3:

TABLE-US-00003 Component % w/w Citric Acid 26 Sodium Bicarbonate 52 Surfactant A 15 Surfactant D 6 Coconut Oil 1

[0200] Procedure: [0201] 1. In the main mixing vessel, combine Citric Acid and Sodium Bicarbonate . [0202] 2. In a side vessel, mix Surfactant A, Surfactant D and Coconut oil until uniform and lump free. [0203] 3. Add side phase to the main vessel and mix until uniform. [0204] 4. Scoop one gram of the powdered mixture into pill press. Apply pressure to compress mixture into a pill/pellet.

Example 4

[0205] A solid cleansing composition was prepared (using the procedure set out above in relation to Example 3) comprising the following ingredients, as shown in Table 4:

TABLE-US-00004 Component % w/w Citric Acid 26 Sodium Bicarbonate 52 Surfactant A 12 Surfactant B 9 Coconut Oil 1

[0206] A comparative composition (hereinafter “Comparative A”) was also prepared (using the procedure set out above in relation to Example 3) comprising the following ingredients, as shown in Table 5:

TABLE-US-00005 Component % w/w Citric Acid 25.85 Sodium Bicarbonate 51.85 Surfactant D 12.31 Surfactant B 9 Coconut Oil 1

[0207] The compositions of Example 4 and Comparative A were tested for foaming ability.

[0208] Foaming ability was tested by a procedure in which a 0.5 w/w% of an aqueous solution was prepared

[0209] by dissolving 2.5 g of the composition (as a powder) in 500 ml of water. 100 ml of the solution

[0210] was added into a 500 cm3 measuring cylinder and shaken 10 times from head to waist. The height of

[0211] foam was then read. This was repeated so as to give 3 results for each composition tested and the

[0212] average foam height was calculated. The results are shown in Table 6.

TABLE-US-00006 Composition Average foam height Example 4 325 cm 10 Comparative A 275 cm

[0213] The composition of Example 4 provided improved foaming compared to the composition of Comparative A.

[0214] The compositions of Example 4 and Comparative A were also subjected to a dissolution test.

[0215] The dissolution test was conducted by adding 1 g of each composition as a tablet to 500 g of water (to provide a 0.2% w/w solution). The formulations were allowed to dissolve without stirring (or any agitation) and were compared visually. The results are shown in FIGS. 1 and 2.

[0216] FIG. 1 shows side views of the formulation comprising the composition of Example 4 on the left and the formulation comprising the composition of Comparative A on the right. FIG. 2 shows vertical views of the formulation comprising the composition of Example 4 on the left and the formulation comprising the composition of Comparative A on the right. FIGS. 1 and 2 show that the composition of Example 4 dissolved in water to provide a clear solution at room temperature, whereas the composition of Comparative A provided a cloudy solution in water that included residue/particles at the bottom of the beaker.

[0217] Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

[0218] All of the features disclosed in this specification (including any accompanying claims, and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

[0219] Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

[0220] The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.