ANTIPERSPIRANT COMPOSITIONS COMPRISING ALUMS

Abstract

An antiperspirant composition having less than 2% free water and comprising a first salt that is M(i)AI(SO.sub.4).sub.2 or Al.sub.2(SO.sub.4).sub.3 and a second salt that is CaX.sub.2, wherein X is CI.sup.−, Br.sup.−, I.sup.−, NO.sub.3.sup.− or mixture thereof, wherein the first salt and the second salt are formulated or contained in a manner that prevents physical interaction between these two components prior to their application and wherein the product also comprises a third salt which is an inorganic base selected from metal hydroxide or carbonate or metal oxide having a water solubility of at least 0.01 g/dm.sup.3 at 20° C.

Claims

1. An antiperspirant composition having less than 2% free water and comprising a first salt that is M(i)Al(SO.sub.4).sub.2 or Al.sub.2(SO.sub.4).sub.3 and a second salt that is CaX.sub.2, wherein X is Cl.sup.−, Br.sup.−, I.sup.−, NO.sub.3.sup.− or mixture thereof, wherein the first salt and the second salt are formulated or contained in a manner that prevents physical interaction between these two components prior to their application and wherein the product also comprises a third salt which is an inorganic base selected from metal hydroxide or carbonate or metal oxide having a water solubility of at least 0.01 g/dm.sup.3 at 20° C.

2. An antiperspirant product according to claim 1, wherein the second salt is calcium chloride.

3. An antiperspirant product according to claim 1 or claim 2, wherein the first salt is potassium aluminium sulphate.

4. An antiperspirant product according to any of the preceding claims, wherein the third salt has a water solubility of less than 5 g/dm.sup.3 at 20° C.

5. An antiperspirant product according to claim 4, wherein the third salt is a magnesium or calcium salt.

6. An antiperspirant product according to claim 5, wherein the third salt is selected from magnesium hydroxide and calcium hydroxide.

7. An antiperspirant product/composition according to any of the preceding claims having a molar ratio of calcium chloride to alum salt that is at least 1:1.

8. An antiperspirant product/composition according to any of the preceding claims, wherein the molar ratio of the first salt to the third salt is from 1:1 to 10:1.

9. An antiperspirant product/composition according to claim 8, wherein the molar ratio of the first salt to the third salt is from 1.2:1 to 4:1.

10. An antiperspirant product/composition according to any of the preceding claims, wherein the first salt has a water content of less than 35% by weight, preferably less than 28% by weight and more preferably less than 20% by weight.

11. An antiperspirant product/composition according to any of the preceding claims, wherein the second salt has a water content of less than 15% and preferably less than 8%.

12. An antiperspirant product/composition according to any of the preceding claims, comprising a cosmetically acceptable liquid carrier material having less than 2% by weight free water.

13. An antiperspirant product/composition according to claim 12, wherein the liquid carrier material comprises a hydrophobic liquid.

14. An antiperspirant product/composition according to claim 12 or claim 13, wherein the liquid carrier material comprises an emollient oil selected from sunflower seed oil and other unsaturated triglyceride oils.

Description

EXAMPLES

[0116] The following examples illustrate certain specific embodiments of the invention and do not limit the scope of the invention. Examples according to the invention are indicated by numbers and comparative examples are indicated by letter. All amounts indicated are percentages by weight, unless otherwise indicated.

Specific Ingredient Details

[0117] (1) Potassium alum (burnt alum) ex Brenntag. Water content 8-12%. Particle Size (D50) 17 micron. [0118] (2) Anhydrous calcium chloride. Less than 7% water, ex Sigma-Aldrich, jet milled to give a particle size (D50) of 15-25 micron.

[0119] (3) Magnesium hydroxide, ex Sigma Aldrich, sieved to give a particle size (D50) of ˜40 micron. [0120] (4) Calcium hydroxide, ex Sigma Aldrich, particle size (D50) ˜7 micron.

Stick Examples

[0121] The stick compositions of Table 1 were prepared as follows. The oils (cyclomethicone and Finsolv TN) were blended together at 95° C. and the waxes (Castorwax MP80 and Polyethylene wax) were melted in with stirring. When the waxes were fully melted, each mixture was cooled to 85° C. The calcium chloride was then added, followed by the alum, and then, if employed, the inorganic base, these powders being fully dispersed into the mixture. Each mixture was then cooled to about 78° C. and, if employed, the sunflower seed oil and Aloe Vera was added and fully dispersed. Finally, the fragrance was added and dispersed. Each mixture was cooled to about 75° C. and poured into stick barrels.

[0122] The antiperspirancy efficacy of the stick compositions of Table 1 were compared with that of a non-antiperspirant body spray control. Test operators applied 0.3 g of each stick composition to one axilla and about 1.5 g of the body spray control to the other axilla of each panellist. This was done once each day for three days. After the third application, panellists were requested not to wash under their arms for the following 24 hours.

[0123] 24 hours after the third and final product application, the panellists were induced to sweat in a hot-room at 40° C. (±2° C.) and 40% (±5%) relative humidity, for 40 minutes. After this period, the panellists left the hot-room and their axillae were carefully wiped dry. Pre-weighed cotton pads were then applied to each axilla of each panellist and the panellists re-entered the hot-room for a further 20 minutes. Following this period, the pads were removed and re-weighed, enabling the weight of sweat generated to be calculated. The sweat weight reduction (SWR) for each panellist was calculated as a percentage (% SWR) and the mean % SWR was calculated according to the method described by Murphy and Levine in “Analysis of Antiperspirant Efficacy Results”, J. Soc. Cosmetic Chemists, 1991(May), 42, 167-197.

TABLE-US-00001 TABLE 1 Example Trade Name Chemical Name A 1 2 3 Finsolv TN C12-15 alkyl 30 30 30 30 benzoate Castorwax Hydrogenated 2 2 2 2 MP80 castor oil Performalene Polyethylene 15 15 15 15 400 wax Calcium Calcium 7.16 7.16 7.16 7.16 Chloride chloride Potassium Potassium 9.37 9.37 9.37 9.37 Alum alum Magnesium Magnesium — 1 1 2 hydroxide hydroxide Florasun 90 Sunflower — — 8 — seed oil Aloe Vera Aloe Barbadensis — — 0.5 — leaf juice Fragrance 1.5 1.5 1.5 1.5 Xiameter Cyclomethicone To 100 To 100 To 100 To 100 PMX-0245

[0124] The irritation potential of the stick formulations were measured using an exaggerated use protocol. Panelists (30 underarms per cell) applied approximately 0.25 g of one test product to one underarm. The 3 applications of the test products were spaced evenly through the day.

[0125] Erythema and dryness were assessed by a trained assessor at regular intervals throughout the test prior to product application on that day. Both attributes were ranked on a scale of 0 to 3.5 (8 point scale in units of 0.5). The reported Irritation scores are the sum of the scores for both attributes.

[0126] Panelists were also asked to report any self-perceived irritation (burning, itching, stinging). Adverse Events were recorded when the erythema or dryness scores reached or exceeded 3, or when the panelists reported significant levels of irritation and asked to stop using the product further.

[0127] Further testing of any product was stopped if more than 30% of panellists had an Adverse Event.

[0128] Results of hot-room and Irritation testing are given in Table 2.

TABLE-US-00002 TABLE 2 Mole ratio SWR Adverse events Irritation score Example base:alum (%) 11 days 29 days 11 days 29 days A Not 45 9 * 3.15 * applicable 1 1:2 39 0 5 1.35 2.8 2 1:2 41 0 2 1.25 1.9 3 1:1 29 — — — — * Test stopped after 11 days due to Adverse Events.

[0129] From Table 2 it can be seen that Example 1 produces significantly lower irritation than Comparative Example A. Example 2 gave still lower irritation, illustrating the benefit of adding an emollient oil as well as the inorganic base. Both Example 1 and 2 gave good hot-room efficacies, i.e. good SWR.

[0130] Example 3 gave a significantly poorer hot-room efficacy than Example 1 or Example 2. It will be noted that the base to alum ratio is this example was outside the preferred range and this is the reason for the impaired hot-room efficacy. The irritancy of Example 3 was not tested, but would have been low.

Aerosols

[0131] The aerosol compositions of Table 3 were prepared as described below.

TABLE-US-00003 TABLE 3 Example Ingredients* B C 4 5 6 7 8 Cyclopentasiloxane 6.646 7.066 6.946 6.866 6.816 6.768 6.638 C12-15 Alkyl Benzoate 2.5 0.72 0.72 0.72 0.72 0.72 0.72 Sunflower seed oil — 1.28 1.28 1.28 1.28 1.28 1.28 Disteardimonium 0.625 0.625 0.625 0.625 0.625 0.625 0.625 Hectorite Propylene Carbonate 0.063 0.063 0.063 0.063 0.063 0.063 0.063 Fragrance 1 1 1 1 1 1 1 Calcium Chloride 2.238 2.238 2.238 2.238 2.238 2.238 2.238 Potassium Alum 2.928 2.928 2.928 2.928 2.928 2.928 2.928 Aloe Barbadensis — 0.08 — 0.08 0.08 — — leaf juice Magnesium Hydroxide — — 0.2 0.2 — — — Calcium Hydroxide — — — — 0.25 0.38 0.51 CAP40* 84 84 84 84 84 84 84 *Chemical names are given, with trade names as indicated in Table 1; the only exception is “CAP40”, which is a trade name for butane, isobutane, propane propellant.

[0132] The cyclomethicone, Finsolv TN, Bentone 38V and sunflower seed oil (with Aloe Vera if used) were mixed for 2 minutes using a 1 inch diameter head Silverson homogeniser operating at 6000 rpm. The propylene carbonate and fragrance were then added with continued mixing at 6000 rpm for a further 5 minutes. The CaCl.sub.2 powder was then gradually added over about 2 minutes, followed by the alum, with continued mixing at 6000 rpm. The Inorganic base (if used) was then added, ensuring good homogenisation. The agitation speed was then increased to 6500 rpm for a further 4 minutes, following which, each composition was poured into a sealable container. Following cooling to ambient temperature, 16 parts of each “base” was transferred into an aerosol can and 84 parts of the indicated propellant was added and the can was sealed with an aerosol valve using standard methods.

[0133] The antiperspirant efficacy of the aerosol compositions was investigated by the same method as with the sticks except that the aerosol compositions were applied using a 2 second spray (corresponds to approximately 2-2.5 g of the composition, inclusive of the propellant).

[0134] The irritation potential of the aerosol compositions were measured in a similar way to those of the sticks except that 4 applications were made per day instead of 3 and panellists applied approximately a 2 second spray (about 2-2.5 g product).

[0135] Results of hot-room and Irritation testing are given in Table 4.

TABLE-US-00004 TABLE 4 Mole ratio SWR Adverse events Irritation score Example base:alum (%) 11 days 29 days 11 days 29 days B not — 6 13 1.95 2.17 applicable C not 45 7 13 2.05 1.98 applicable 4 1:2.8 43 2 7 1.33 1.43 5 1:2.8 40 5 6 1.32 1.47 6 1:2.8 40 3 7 1.39 1.44 7  1:1.82 35 0 5 1.24 1.41 8  1:1.37 39 2 4 1.21 1.37

[0136] The results show that Comparative Examples B and C gave relatively high levels of irritation and that the presence of sunflower seed oil and Aloe Vera in Comparative Example C did not mitigate this problem. Addition of magnesium hydroxide to give Examples 4 and 5 did, however, lead to significantly reduced irritation. The results from Examples 6 to 8 indicate that a similar benefit was obtained on addition of calcium hydroxide across a range of base:alum molar ratios.