SULFATE-FREE PERSONAL CARE COMPOSITIONS AND METHODS FOR USING SUCH COMPOSITIONS

Abstract

The present invention relates to sulfate-free aqueous personal care composition comprising a surfactant system comprising at least one methyl oleoyl taurate, one isethionate and one alkoxylated sulfosuccinate, and from about 0.2 pbw to about 15 pbw of a conditioning agent. It is also directed toward the use of such a composition for washing keratin substrates, in particular the hair or the scalp.

Claims

1. A sulfate-free aqueous personal care composition comprising: i) from about 2 pbw to about 20 pbw of a surfactant system comprising at least: a) one methyl oleoyl taurate of formula R.sup.aCON(CH.sub.3)CH.sub.2CH.sub.2SO.sub.3X.sup.a, in which R.sup.a is the hydrocarbon radical of oleic acid and X.sup.a is a counterion, b) one isethionate of formula R.sup.bCOOCH.sub.2CH.sub.2SO.sub.3 X.sup.b, in which R.sup.b is a substituted or unsubstituted alkyl, alkenyl, aryl or alkylaryl group having 6 to 30 carbon atoms, and X.sup.b is a counterion, and c) one alkoxylated sulfosuccinate, and ii) from about 0.2 pbw to about 15 pbw of a conditioning agent.

2. The composition of claim 1, wherein the isethionate (b) is of formula R.sup.bCOOCH.sub.2CH.sub.2SO.sub.3 X.sup.b, with R.sup.b being an unsubstituted alkyl group having 6 to 30 carbon atoms.

3. The composition of claim 1, wherein the alkoxylated sulfosuccinate (c) is an alkoxylated sulfosuccinate of formula R.sup.c—O—(CH.sub.2CH.sub.2O).sub.nC(O)CH.sub.2CH(SO.sub.3X.sup.cCO.sub.2X.sup.c, wherein n ranges from 1 to 20, R.sup.c is a substituted or unsubstituted alkyl, alkenyl, aryl or alkylaryl group having 6 to 30 carbon atoms, and X.sup.c is a counterion.

4. The composition of claim 1, wherein the alkoxylated sulfosuccinate (c) is an alkoxylated sulfosuccinate of formula R.sup.c—O—(CH.sub.2CH.sub.2O).sub.nC(O)CH.sub.2CH(SO.sub.3X.sup.c)CO.sub.2X.sup.c, wherein n ranges from 2 to 20, R.sup.c is an unsubstituted alkyl group having 6 to 30 carbon atoms, for instance 7 to 24 carbon atoms, for instance 7 to 21 carbon atoms, and X.sup.c is a counterion.

5. The composition of claim 1, wherein the composition further comprises one amphoteric or zwitterionic surfactant selected from the group consisting of (1) amphoacetates and diamphoacetates, (2) sultaines and (3) alkylbetaines.

6. The composition of claim 1, wherein the weight ratio of alkoxylated sulfosuccinate (c) to methyl oleoyl taurate (a) is greater than or equal to 1, based on the weight percent of each surfactant in the final composition.

7. The composition of claim 1, wherein the weight ratio of alkoxylated sulfosuccinate (c) to isethionate (b) is greater than or equal to 1, based on the weight percent of each surfactant in the final composition.

8. The composition of claim 1, wherein the total amount of surfactants ranges from 5 to 15 pbw, relative to the total weight of the composition.

9. The composition of claim 1, wherein the conditioning agent is a cationic or ampholytic conditioning agent.

10. The composition of claim 1, characterized in that it is a personal care cleansing composition.

11. A method comprising washing keratin substrates using the composition according to claim 1.

12. The composition of claim 2, wherein the isethionate (b) is of formula R.sup.bCOOCH.sub.2CH.sub.2SO.sub.3 X.sup.b, with R.sup.b being an unsubstituted alkyl group having 7 to 24 carbon atoms.

13. The composition of claim 12, wherein the isethionate (b) is of formula R.sup.bCOOCH.sub.2CH.sub.2SO.sub.3 X.sup.b, with R.sup.b being an unsubstituted alkyl group having 7 to 21 carbon atoms.

14. The composition of claim 6, wherein the weight ratio of alkoxylated sulfosuccinate (c) to methyl oleoyl taurate (a) is greater than 1, based on the weight percent of each surfactant in the final composition.

15. The composition of claim 7, wherein the weight ratio of alkoxylated sulfosuccinate (c) to isethionate (b) is greater than 1, based on the weight percent of each surfactant in the final composition.

16. The method of claim 11, wherein the keratin substrates are the hair or the scalp.

Description

EXAMPLES

[0132] The invention will now be described in further detail by way of the following non limiting examples, wherein the abbreviations have the usual meaning in the art. The temperatures are indicated in degrees centigrade (° C.) and the other parameters in the respective current units. Water amount indicated as “q.s.” are intended to be “the amount required to complete to 100%”.

[0133] Viscosity Measurement

[0134] The viscosity of each composition was measured after 24-hours in a temperature-controlled room (21±3° C.), using a Brookfield Viscosimeter Model DV-II+ at 10 RPM, with a RV spindle 4 or 5. The viscosity value was always taken after a stabilization time of 1 min.

Example 1

[0135] The following sulfate-free shampoo compositions were prepared.

[0136] The starting materials used are identified by the INCI names and/or by the commercial references. All ingredients are expressed by weight percent of the total formulation and as level of active ingredients.

TABLE-US-00001 Comparative Comparative Formulation Formulation Formulation Formulation 1 1 2 2 Mackanate ® EL 6.0 6.0 6.0 6.0 (Disodium Laureth Sulfosuccinate) Mackam ® CBS-50G 4.0 4.0 — — (Cocamidopropyl Hydroxysultain) Miranol ® Ultra L32 — — 4.0 4.0 (Sodium Lauroamphoacetate) Pureact ® I-78C 2.0 2.0 2.0 2.0 Sodium Cocoyl Tsethionate) Geropon ® T-77 — 1.8 — 1.8 (Sodium Methyl Oleoyl Taurate) Geropon ® TC-42 LQ 1.8 — 1.8 — (Sodium Methyl Cocoyl Taurate) Mackamide ® CPA 1.5 1.5 1.5 1.5 (Cocamide MIPA) sodium chloride 1.63 1.63 1.3 1.3 Jaguar ® LS 0.3 0.3 0.3 0.3 (Hydroxypropyl Guar hydroxypropyltrimonium chloride) Citric acid solution (50%) q.s q.s q.s q.s Kathon ® CG 0.05 0.05 0.05 0.05 (Methylchloroisothiazolinone, Methylisothiazolinone) De-ionized water Up to 100 Up to 100 Up to 100 Up to 100 pH 5.4 5.4 6.0 6.0 Brookfield Viscosity @ <500 Between <1,000 Between 10 RPM, RV spindle 2,000 26,000 and 4 or 5 (mPa .Math. s) and 5,000 29,000

[0137] Formulation Procedure

[0138] Add 24 parts of de-ionized water in a tared beaker A under continuous stirring and heat at 65° C. Add Mackamide® CPA and mix at 100 RPM. After 10 minutes, add Pureact®I-78C and let under stirring during 30 minutes. Stop heating and let the mixture under stirring until it comes back at 30° C. If necessary, compensate for water loss that has occurred during heating step.

[0139] In another vessel, charge 26 parts of de-ionized water. Add Jaguar LS in the vessel and add a few drops of citric acid solution (50%) under stirring, until the solution becomes clear. Add Miranol® Ultra L32 (or Mackam® CBS-50G) under stirring, followed by Mackanate® EL. Add the pre-mix of beaker A into the main vessel under continuous stirring at 100 RPM during 10 minutes. Add Geropon® T-77 in the form of a 25 wt % dilution in water (or Geropon TC-42LQ) and stir during 10 minutes. Adjust pH between 5.0 and 6.0 with a 50% solution of citric acid, add Kathon®CG and add the required amount of sodium chloride under stirring. Add de-ionized water up to 100 parts.

[0140] Performances

[0141] Formulation 1, which includes the particular combination of anionic surfactants in accordance with the invention, is a cleansing composition displaying acceptable viscosity (above 1,500 cps) contrary to Comparative Formulation 1.

[0142] Formulation 2, which includes the particular combination of anionic surfactants in accordance with the invention too, is an alternative cleansing composition which displays also acceptable viscosity (between 1,500 and 50,000 cps), contrary to Comparative Formulation 2.

[0143] Sensorial tests confirmed that Formulations 1 and 2 of the invention exhibit at the same time good foaming properties and good conditioning.

[0144] These examples illustrate that the particular combination of surfactants required according to the invention, namely the combination of a methyl oleoyl taurate with one isethionate of the invention and with one alkoxylated sulfosuccinate, is critical to achieve good foaming and conditioning properties, while maintaining an acceptable viscosity in a sulfate-free surfactant chassis.

Example 2

[0145] The following sulfate-free shampoo compositions were prepared.

[0146] The starting materials used are identified by the INCI names and/or by the commercial references. All ingredients are expressed by weight percent of the total formulation and as level of active ingredients.

TABLE-US-00002 Comparative Formulation Formulation 3 3 Mackanate ® EL — 6.0 (Disodium Laureth Sulfosuccinate) Mackanate LO 100 6.0 — (Disodium Lauryl Sulfosuccinate) Mackam ® CBS-50G 4.0 4.0 (Cocamidopropyl Hydroxysultain) Pureact ® I-78C 2.0 2.0 (Sodium Cocoyl Isethionate) Geropon ® T-77 1.8 1.8 (Sodium Methyl Oleoyl Taurate) Mackamide ® CPA 1.5 1.5 (Cocamide MIPA) sodium chloride 2.0 2.6 Jaguar ® LS 0.4 0.4 (Hydroxypropyl guar Hydroxypropyltrimonium chloride) Citric acid solution (50%) q. s q. s De-ionized water Up to 100 Up to 100 pH 5.3 5.4 Brookfield Viscosity Between 7,000 Between 7,000 @10 RPM, RV and 10,000 and 10,000 spindle 4 or 5 (mPa .Math. s)

[0147] Formulation Procedure

[0148] Add 27 parts of de-ionized water in a tared beaker A under continuous stirring and heat at 65° C. Add Mackamide® CPA and mix at 100 RPM. After 10 minutes, add Pureact®I-78C. After 5 minutes add Geropon® T-77 and let under stirring during 30 minutes. Stop heating and let the mixture under stirring until it comes back at 30° C. If necessary, compensate for water loss that has occurred during heating step.

[0149] In another vessel, charge 30 parts of de-ionized water. Add Jaguar LS in the vessel and adjust pH at 5.5 with a 50% solution of citric acid, under stirring, until the solution becomes clear. Add Mackam® CBS-50G under stirring, followed by Mackanate® EL (resp. Mackanate® LO 100). Add the pre-mix of beaker A into the main vessel under continuous stirring at 100 RPM during 10 minutes. Add sodium chloride up to achieve a targeted viscosity of [7,000-10,000 mPa.Math.s] at 10 RPM and adjust pH at 5.5±0.2 with a 50% solution of citric acid under continuous stirring. Add de-ionized water up to 100 parts.

[0150] Performances

[0151] Viscosity of each formulation has been adjusted with added salt (sodium chloride) to yield formulations having a similar viscosity within a satisfactory range (between 7,000 and 10,000 cps).

[0152] In this viscosity range the performances of Formulation 3 (which includes the particular combination of anionic surfactants including an alkoxylated sulfosuccinate in accordance with the invention) have been compared to the performances of Comparative Formulation 3, in terms of sensorial assessment on hair tresses, foam volume and flash foam, according to the following methodologies.

[0153] Sensorial Assessment on Hair Tresses

[0154] Flat Calibrated tresses of bleached Caucasian hair, weighing about 10 grams, length of hair: 21 cm below clip and 3 cm width were used. They were purchased from Kerling International Haarfabik GmbH, Donaustr. 7, D-71522 Backnang-Waldrems in Germany. Sensorial analysis was performed by a trained expert panellist, following the standardized protocol described below.

[0155] Prior to being actually shampooed, the hair tresses were first cleansed with a 10% active sodium laureth sulfate (SLES) solution. Each hair tress was then wetted under flowing tap water (controlled flow 1100 mL+/−40 mL per 10 sec) at controlled temperature (36.5° C.±1° C.) during 1 minute. 1 ml of shampoo formulation was applied over the entire length of the hair tress and foam was produced by massaging the hair tress from the top to the bottom during 1 min 30 sec with one's hand. The speed at which the foam forms after 15 seconds (so-called “flash-foam”) was scored (a score of 1 corresponds to a very slow-forming foam; a score of 2, a slow-forming foam; a score of 3, a medium rapid forming foam; a score of 4, a rapid forming foam; a score of 5 a very rapid forming foam).

[0156] The foam generated in the hands and on hair tress was then collected in a conic beaker of 250 mL. The amount of foam was assessed and the foam quality attributes were noted (whiteness, density, richness). Then the hair tress was rinsed during 1 min 15 sec, under flowing tap water at controlled flow, with gentle squeezing of the hair tress from roots to tips with the fingers. After rinsing, the excess water was removed by squeezing the hair tress with two fingers, and the time necessary to detangle the hair tress with a wide-tooth comb was monitored.

[0157] Sensorial analysis on bleached hair tresses were performed by one expert panelist. Results were the following:

TABLE-US-00003 Comparative Formulation Formulation 3 3 flash foam 2.5 3.0 [score 1 (very low)-5 (very high)] Foam volume (ml) 30 ml 50 ml Delangling lime 6 min 12 sec 4 min 09 sec

[0158] Formulation 3 (which includes the particular combination of anionic surfactants including an alkoxylated sulfosuccinate in accordance with the invention) exhibits overall better performances (in terms of speed of foam formation, foam volume and time necessary to achieve hair tress detangling) compared to Comparative Formulation 3.

[0159] These Examples demonstrate that the compositions according to the invention makes it possible to achieve an acceptable compromise between viscosity of the composition, foaming properties and conditioning.