Composition of aluminum dichlorohydrate of high performance comprising buffering agent and calcium and method of making thereof

Abstract

An antiperspirant active composition of high efficacy includes aluminum dichlorohydrate (ADCH), a buffering agent, and a calcium salt. The buffering agent may be an amino acid, such as glycine. The composition has an aluminum to chloride (Al:Cl) molar ratio ranging from 0.91 to 1.25 and a size exclusion chromatography HPLC peak 4 of at least 30% and peak 5 of at least 10%.

Description

COMPOSITION OF ALUMINUM DICHLOROHYDRATE OF HIGH PERFORMANCECOMPRISING BUFFERING AGENT AND CALCIUM AND METHOD OF MAKING THEREOFCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of the filing date of U.S. Provisional Application No. 63 / 533,046, filed August 16, 2023, the disclosure of which is incorporated herein by reference.BACKGROUND

[0002] Basic aluminum chlorides are known effective antiperspirants. Basic aluminum chlorides used as antiperspirants include aluminum chlorohydrate (ACH) having an Al: Cl molar ratio ranging from 1.91 to 2.1 , aluminum sesquichlorohydrate (ASCH) having an A1:C1 molar ratio ranging from 1.26 to 1.90, or aluminum dichlorohydrate (ADCH) having an A1:C1 molar ratio ranging from 0.91 to 1.25.

[0003] To improve antiperspirant efficacy of basic aluminum chlorides, one conventional method involves introducing zirconium compounds and amino acids into basic aluminum chlorides for efficacious aluminum-zirconium antiperspirants. However, there are drawbacks. First, aluminum-zirconium antiperspirant actives are expensive due to the high cost of zirconium. Second, aluminum-zirconium antiperspirant actives cannot be used in aerosol formulations due to the potential hazard of zirconium compounds.

[0004] Another conventional method involves manufacturing basic aluminum chloride solutions with a low A1:C1 molar ratio. These solutions have increased efficacy due to the higher quantity of depolymerized species, such as aluminum monomers and dimers, as demonstrated by HPLC peak 5. However, there are drawbacks. First, irritancy is challenging for formulation, specifically with skin compatibility and fragrance stability. Second, the spray dryer, which is used to turn a solution into a powder, is quickly corroded because the high acid content causes heavy acid loss. Technically, it is also very challenging to activated the HPLC peak 4. Therefore, there is no commercial activated ADCH having an A1:C1 molar ratio from 0.9 to 1.25.

[0005] Conventionally, solutions with high HPLC peak 4 of at least 30% and low peak 5 of less than 10% are created when ACH and ASCH solutions are diluted and thermally treated. However, these solutions are not stable and revert to HPLC peak 3 aluminum species during cooling and aging. Therefore, to preserve the high HPLC peak 4, the solutions are quickly dried to powders.

[0006] This process as known in the art of dilution, heat treatment, and drying, however, cannot be used with ADCH because such process cannot afford high peak 4 aluminum salts that remain stable to be dried into powders. Usually, the activated ADCH salt has high HPLC peak 4 of less than 30% and peak 5 of at least 20%. Even though an activated ADCH solution with high HPLC peak 4 can be produced under very diluted conditions, high HPLC peak 4 reverts to HPLC peak 3 and heavy loss of acid occurs upon drying.

[0007] Activated ACH and ASCH solutions and powders can also be produced through an energyefficient method of activation, i.e., in the presence of calcium and glycine. These solutions have high HPLC peak 4 aluminum species and can be prepared and maintained at a high concentration of at least 30% by weight. Both commercially activated ACH-Ca-glycine and activated ASCH-Ca-glycine, however, have low HPLC peak 5.

[0008] It is highly desirable to provide activated ADCH products having both high HPLC peak 4 and peak 5 with superior efficacy. It is also highly desirable to provide an effective process to manufacture the activated ADCH products having both high HPLC peak 4 and peak 5 with superior efficacy.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 is27Al NMR of Comparative Example 1 of an activated ASCH-Ca-Glycine solution.

[0010] FIG. 2 is27Al NMR of Example 1 of an activated ADCH-Ca-Glycine solution, demonstrating a high amount of Al monomers at 0 ppm with a sharp peak at 0 ppm.BRIEF SUMMARY

[0011] The present disclosure is directed to an antiperspirant active composition of high efficacy including aluminum dichlorohydrate (ADCH), a buffering agent, and a calcium salt. The buffering agent may be an amino acid, such as glycine. The composition has an aluminum to chloride (Al: Cl) molar ratio ranging from 0.91 to 1.25 and a size exclusion chromatography HPLC peak 4 of at least 30% and peak 5 of at least 10%. The resulting solution has improved stability so that the solutions can be dried into a powdered form before the solution gels.

[0012] One aspect of the disclosure is directed to an antiperspirant active powder including an activated aluminum salt, a buffering agent, and a calcium salt. The buffering agent may be an amino acid. An HPLC peak 4 may be at least 30% and an HPLC peak 5 may be at least 10%. An aluminum to chlorine (A1:C1) molar ratio may range from 0.91 to 1.25.

[0013] In some examples, the HPLC peak 4 may be 85% or less, and the HPLC peak 5 may be 50% or less.

[0014] Another aspect of the disclosure is directed to an antiperspirant active solution including an activated aluminum salt, a buffering agent, and a calcium salt. The buffering agent may be an amino acid. An HPLC peak 4 may be at least 30% and an HPLC peak 5 may be at least 10%. An aluminum to chlorine (A1:C1) molar ratio may range from 0.91 to 1.25.

[0015] In some examples, the aluminum salt may be represented by Chemical Formula 1: A12(OH)e-Xa. X may be selected from the group consisting of Cl and NO3, and a may range from 1.6 to 6.6.

[0016] In some examples, the activated aluminum salt may be activated aluminum dichlorohydrate (activated ADCH).

[0017] In some examples, the buffering agents can be amino acids. The amino acids may be glycine, alanine, valine, arginine, etc. The other buffering agents can be betaine, urea, or a mixture thereof.

[0018] In some examples, the calcium salt is calcium chloride, calcium nitrate, calcium citrate, calcium carbonate, calcium hydroxide, or a mixture thereof. A calcium to aluminum (Ca:Al) molar ratio may range from 1:20 to 1:6.

[0019] In some examples, the amino acid may be glycine, and the calcium salt is calcium chloride. A glycine to aluminum (glycine: Al) molar ratio may range from 1:10 to 1:1.

[0020] Another aspect of the disclosure is directed to a topical composition including an effective amount of the antiperspirant active powder as described above and a dermatologically acceptable carrier. In some examples, the topical composition may be in the form of a liquid for a roll-on or porous applicator, a lotion, a cream, a soft-solid stick, a solid stick, or an aerosol. In some examples, the topical composition may further include cyclomethicone, behenyl alcohol, polypropylene glycol (PPG) 15 stearyl ether, isopropyl myristate, polyethylene, alkyl cl2-15 benzoate, hydrogenated castor oil, talc, and colloidal silica.

[0021] Another aspect of the disclosure is directed to an antiperspirant active powder including activated aluminum dichlorohydrate (activated ADCH, or AADCH), glycine, and a calcium salt. An HPLC peak 4 may be at least 30% and an HPLC peak 5 may be at least 10%. An aluminum to chlorine (A1:C1) molar ratio may range from 0.91 to 1.25.

[0022] In some examples, the HPLC peak 4 may be 85% or less, and the HPLC peak 5 may be 50% or less.

[0023] In some examples, the calcium salt is calcium chloride, calcium nitrate, calcium citrate, calcium carbonate, calcium hydroxide, or a mixture thereof. A calcium to aluminum (Ca:Al) molar ratio may range from 1:20 to 1:6.

[0024] In some examples, a glycine to aluminum (glycine: Al) molar ratio may range from 1:10 to 1:1.DETAILED DESCRIPTION

[0025] An activated aluminum dichlorohydrate (ADCH) solution having both high HPLC peak 4 and peak 5 may be created by acid activation of ADCH in a solution with a calcium salt and a buffering agent. The presence of the buffering agent and the calcium in the activated ADCH solution may provide more depolymerized and activated aluminum species, leading to higher performance. The acid activation may preserve high HPLC peak 4 aluminum species and may generate more depolymerized aluminum species aluminum monomers and dimers represented by HPLC peak 5, such that super-activated aluminum species are produced. The buffering agent may be a water-soluble amino acid. The amino acid, includes,but not limited to, glycine, alanine, valine, arginine, etc. The other buffering agents can be betaine, urea, or a mixture thereof. The buffering agent is preferably glycine.

[0026] In one embodiment, the super-activated ADCH-Ca-Glycine solution may have an HPLC peak 4 ranging from 30% to 85%, more preferably from 50% to 80%, and most preferably from 60% to 75%. The super-activated ADCH-Ca-Glycine solution may have an HPLC peak 5 ranging from 10% to 50%, more preferably from 15% to 40%, and most preferably from 20% to 35%.

[0027] The super-activated ADCH-Ca-Glycine solution may then be dried into a powdered form.Acid-activated ADCH

[0028] ADCH may be activated through acid addition to activated aluminum chlorohydrate (ACH) or activated aluminum sesquichlorohydrate (ASCH) in solutions that include a calcium salt and a buffering agent and that that have high HPLC peak 4. These solutions containing activated ACH or activated ASCH are referred to as activated ACH-Ca-Glycine or activated ASCH-Ca-Glycine, respectively. The activated ACH-Ca-Glycine and activated ASCH-Ca-Glycine solution may have an HPLC peak 4 of at least 40%, more preferably at least 50%, and most preferably at least 60%.

[0029] The acid activation may preserve high HPLC peak 4 aluminum species and may generate more depolymerized aluminum species aluminum monomers and dimers, such that the super-activated aluminum species are produced. As described in connection with the indirect process, the acid addition may be performed at low temperature with a high concentration of activated ACH-Ca-Glycine or activated ASCH-Ca-Glycine. For a solution that does not include calcium and glycine, the total solids content may be 20 - 25% by weight. For a solution that includes calcium and glycine, the total solids content may be 25 - 40% by weight.

[0030] The activated ADCH-Ca-Glycine solution may then be dried into a powder.

[0031] The aluminum salt may be represented by Chemical Formula 1: Ah(OH)6-aXa. “X” may be Cl or NO3. Preferably, “X” is Cl. “a” may range between 1.6 to 6.6. Preferably, “a” may range from 1.6 to 4. Most preferably, “a” may range from 1.6 to 2.2 so that A1:C1 molar ratio might be 0.91 to 1.25.

[0032] Calcium may facilitate the activation of aluminum polymers to form high HPLC peak 4 aluminum species at high concentrations. The calcium salt may be calcium chloride, calcium nitrate, calcium citrate, calcium carbonate, calcium hydroxide, or mixtures thereof. The calcium salt is preferably calcium chloride. The calcium to aluminum (Ca:Al) molar ratio may range from 1:20 to 1:6 and may preferably range from 1:11 to 1:8.

[0033] Similarly, glycine as the buffering agent may also facilitate the activation of aluminum polymers to form high HPLC peak 4 aluminum species at high concentrations. The buffering agent may balance the pH of the activated ADCH-Ca-Glycine solution with a stabilized peak 4, which improves its compatibility with an under-arm environment and improves formulation with enhanced efficacy. The buffering agent may also prevent aluminum species from further polymerization.

[0034] The buffering agent may be a water-soluble amino acid. The amino acid, includes, but not limited to, glycine, alanine, valine, arginine, etc. The other buffering agents can be betaine, urea, or a mixture thereof. The buffering agent is preferably glycine. The glycine to aluminum (glycine: Al) molar ratio may range from 1:10 to 1:1 and preferably range from 1:4 to 1:2.

[0035] The acid may be HC1, HNO3, AICI3, or Al(NOs)3. Preferably, the acid is HC1, which is shown in the examples to demonstrate superior activation by keeping the HPLC peak 4 and peak 5 high.Preparation Through Indirect Method

[0036] Under the indirect process, an activated ADCH-Ca-Glycine solution may be created by adding an acid to activated ACH-Ca-Glycine or activated ASCH-Ca-Glycine solution at a temperature below 50°C. A temperature higher than 50°C may accelerate the degradation of HPLC peak 4.Preparation Through Direct Method

[0037] Under the direct process, an activated ADCH-Ca-Glycine solution may be created by adding an acid to activated ACH-Ca-Glycine or activated ASCH-Ca-Glycine solution at a temperature ranging from 80°C to 100°C. Preferably, the temperature may range from 85°C to 100°C.

[0038] Alternatively, an activated ADCH-Ca-Glycine solution may be created by adding an acid to a solution including ACH or ASCH, CaCL, glycine, and water and thermally treating the solution at a temperature ranging from 80°C to 100°C and for a time ranging from two to ten hours. Preferably, the temperature may range from 85 °C to 100°C.Direct v. Indirect Method

[0039] An activated ADCH-Ca-Glycine solution prepared through the indirect process may have a higher HPLC peak 4 in comparison to an activated ADCH-Ca-Glycine solution prepared through the direct process. The thermal treatment step in the direct process may destabilizes HPLC peak 4 aluminum species in the activated ADCH solution. Preferably, an activated ADCH-Ca-Glycine solution is prepared by the indirect process.Stability of the Stock Solution

[0040] The HPLC peak 4 of the activated ADCH-Ca-Glycine solution may decrease upon aging. The amount of calcium salt and buffering agent play a role in producing a stable stock solution. If the calcium or glycine concentration is too high, the activated ADCH-Ca-Glycine solution may gel or quickly form precipitates. To preserve both high HPLC peak 4 and peak 5, the activated ADCH-Ca-glycine solution may be dried to powdered form.Drying the Stock Solution

[0041] The stock solution may be spray dried, freeze dried, or drum dried into a powdered form. Preferably, the stock solution may be spray dried. The moisture content may be measured by loss on drying (LOD). The LOD for the powder may be less than 12%, preferably less than 10%, and most preferably less than 8%.

[0042] Drying the stock solution is challenging because hygroscopic properties of calcium chloride and ADCH. The moisture content of the stock solution must be controlled to ensure that the powder is free flowing, does not agglomerate, and can be easily formulated into finished products.HPLC (Size Exclusion Chromatography)

[0043] The degree of polymerization of aluminum complexes may be determined through size exclusion chromatography (SEC) operated via a high-performance liquid chromatography (HPLC) instrument. For this process, the highest molecular weight Al species may be eluted first and designated as peaks 1 and 2 (or Band I). Peaks 3 (or Band II) and 4 (or Band III) may indicate intermediate molecular weight Al complexes. Peak 5 (or Band IV) may indicate the lowest molecular weight Al complexes, including monomers and dimers. The relative area of one or more peaks is determined to characterize the distribution of polymeric species in Al complexes.

[0044] The activated ADCH-Ca-Glycine solution may have an HPLC peak 4 of at least 30%, preferably at least 40%, and most preferably at least 50%. The activated ADCH-Ca-Glycine solution may have an HPLC peak 4 ranging from 30 % to 85%, preferably 50% to 80%, and most preferably 60% to 75%. The activated ADCH-Ca-Glycine solution may have an HPLC peak 5 ranging from ranging from 10% to 50%, preferably from 15% to 40%, and most preferably from 20% to 35%.Nuclear Magnetic Resonance Spectroscopy

[0045] 27Al Nuclear Magnetic Resonance (NMR) may be used to identify the molecular structures of different aluminum species in the aluminum antiperspirant salts. The measurements may include the antiperspirant salt in solution form. The measurements may also include the powder form dissolved in deuterated water for a 10% by weight solution. Data may be collected using a Varian Inova 400 instrument at 104.2 MHz.

[0046] A sharp peak at 0 ppm by27Al NMR may indicate monomeric octahedral Al species. A peak at 4-5 ppm may indicate octahedral Al dimers. A sharp peak at about 63 ppm from a tetrahedral Al species may indicate Al species comprising one tetrahedral Al center. The other twelve octahedral Al centers in this compound may have peaks that are too broad to be detected. The broad peak at about 69-72 ppm may be due to HPLC peak 4 aluminum polymers. The activated ADCH solution containing calcium and glycine of high efficacy may demonstrate a high amount of Al monomers at 0 ppm.Topical Compositions

[0047] A topical composition including the ADCH-Ca-Glycine powders may be in the form of liquid for a roll-on or a porous applicator, a lotion, a cream, a soft-solid stick, a solid stick, or an aerosol.

[0048] The composition may include inactive ingredients known in the art, including, but not limited to, cyclomethicone, behenyl alcohol, polypropylene glycol (PPG) 15 stearyl ether, isopropyl myristate, polyethylene, alkyl cl2-15 benzoate, hydrogenated castor oil, talc, or colloidal silica. The composition may also include stearyl alcohol, dimethicone, sunflower oil, steareth 100, PEG-8, fragrance, mineral oil, or polyethylene glycol 400.

[0049] To create an antiperspirant stick, the inactive ingredients may be mixed at a temperature ranging from 80°C to 85°C. The activated ADCH-Ca-Glycine powders may be added in the bulk composition at a temperature ranging from 74°C to 80°C. The batch may be cooled to a temperature ranging from 65°C to 75°C. The cooled batch may be poured into molds and cooled further to approximately 50°C.EXAMPLESComparative Example 1 : Activated ASCH-Ca-Glycine Powder

[0050] 50%ACH solution and HC1 were mixed and agitated for about 15 minutes to form an ASCH solution with a target mole ratio of A1:C1 of 1.70:1. Subsequently, water and CaCl2were added and agitated for 15 minutes. Glycine was then added and agitated for about 30 minutes until completely dissolved. Then, the solution was heated to about 90°C and thermally treated for about 4 hours. Table 1 provides the weight for each component in Comparative Example 1.Table 1: Preparation of Comparative Example 1

[0051] The solution was then spray dried into powdered form, followed by milling.Example 1: Acid Activated ADCH-Ca-Glycine Powder

[0052] An activated ADCH solution was created according to the procedure for Comparative Example 1 , where HC1 was added to the A ASCH-Ca-Glycine solution at a temperature below 50°C. Specifically, the solution from Comparative Example 1 was cooled down to 33°C. 22% w / w HC1 solution was added at a temperature below 50°C and mixed with the activated ASCH-Ca-Glycine solution of Comparative Example 1. Table 2 provides the weight for each component in Example 1.Table 2: Preparation of Example 1

[0053] After the solution was homogenous, the solution was spray dried into powdered form, followed by milling.Table 3: Impact of Additional Acid Activation Step on HPLC Peak

[0054] As shown in Table 3, the acid activation step at a temperature below 50°C in Example 1 resulted in a powder with a high HPLC peak 5 of 20.94%. In comparison, the HPLC peak 5 for the powder in Comparative Example 1 is 4.98%.

[0055] Additionally, FIG. 1 and FIG. 2 show the27Al NMR of Comparative Example 1 and Example 1, respectively. As shown in the figures, the activated ADCH solution containing calcium and glycine demonstrate a high amount of Al monomers at 0 ppm.Examples 2a and 2b: Activated ADCH-Ca-Glycine Powder through the indirect process

[0056] 50%ACH solution and HC1 were mixed a temperature below 50°C to form an ASCH solution. Subsequently, water, CaCL, and glycine were then added to the ASCH solution and agitated for about 30 minutes until a clear solution was obtained. Table 4 provides the weight for each component in Examples 2a and 2b. Then, the solution was thermally treated at 90°C for about 4 hours.Table 4: Preparation of Examples 2a and 2b

[0057] Next, 22% w / w HC1 solution was used as an acid to prepare the feed solutions for a A1:C1 molar ratio of 1.20:1 and 1.0:1. The HC1 solutions were added to the feed solutions at 33°C.Table 5: Preparation of Activated ADCH Solution Through Indirect ProcessTable 6: Properties of Activated ADCH Solution Through Indirect Process

[0058] As shown in Table 6, activated ADCH solutions prepared through the indirect process result in high HPLC peaks 4 and 5.Examples 3a and 3b: Activated ADCH-Ca-Glycine Powder through the direct process

[0059] ADCH solutions were created by mixing 50%ACH solution and HC1 and sampling the solutions to confirm A1:C1 ratios of about 1.0:1 and 1.20:1.Table 7: Preparation of ADCH Solution Through Direct Process

[0060] ADCH-Ca-Glycine solutions were created by adding water, CaCl2, and glycine to the ADCH solutions for 2.2 molar aluminum strength solutions. Then, the solutions were thermally treated for aluminum activation for about 4 hours at a temperature between 85 °C to 100°C to form an activated ADCH-Ca-Glycine solutions. The activated ADCH-Ca-Glycine solutions were then spray dried into powdered forms.Table 8: Preparation of Activated ADCH Solution Through Direct ProcessTable 9: Properties of Activated ADCH Solution Through Direct Process

[0061] As shown in Table 9, activated ADCH solutions prepared through the direct process result in high HPLC peak 5. Additionally, the activated ADCH-Ca-Glycine powders produced by the indirectprocess have a higher HPLC peak 4 than the activated ADCH-Ca-Glycine powders produced from the direct process.Example 4: Comparison of activated ADCH-Ca-Glycine Powders by Acid Addition with and without Heat Treatment

[0062] Powder A was created through the indirect method. HC1 was added to the activated ASCH- Ca-Glycine solution like Comparative Example 1 except with a lower glycine content and at 33 °C and then spray dried into powdered form.

[0063] Powder B was created through the direct method. HC1 was added to the activated ASCH- Ca-Glycine solution like Comparative Example 1 except at a lower glycine content, and the resultant solution was heated to about 90°C and maintained at 90°C for 2 hours, then resultant solution was spray dried into powdered form.Table 10: Impact of Heat Treatment on HPLC Peak

[0064] As shown in Table 10, powders produced through both the indirect and direct methods result in high HPLC peaks 4 and 5.Example 5: Topical Compositions Containing Activated ADCH-Ca-Glycine

[0065] Preparation of Antiperspirant Sticks

[0066] The ingredients in Table 1 Iwere mixed in a stainless-steel vessel at a temperature ranging from 80°C to 85 °C. For Example 1 and Comparative Example 1, the powders from Example 1 and Comparative Example 1 , respectively, were added in the bulk composition at a temperature ranging from 74°C to 80°C and mixed. Mixing was continued, and the batch was subjected to a cooling to a temperature ranging from 65°C to 75°C. The hot contents were poured into molds. Solid antiperspirant sticks, with uniform and random orientation of crystals, were obtained upon cooling below approximately 50°C.Table 11: Contents of Antiperspirant SticksTable 12: Stick Formulation ParametersMethod for Active Extraction

[0067] Antiperspirant sticks made with activated ADCH-Ca-Glycine powders were evaluated for active uniformity by analysis of % chloride (represented by the %C1 distribution in the formulation) in top, middle and bottom section of the sticks. Each sample of the antiperspirant sticks weighing 0.5 g were mixed with 200 mL of demineralized water and 3 mL of concentrated nitric acid. The mixture was boiled for 15 to 18 minutes to melt the sample. The mixture was cooled to room temperature 25+1° C and titrated with 0.1N silver nitrate solution using a chloride analyzer.Table 13: Effect of Glycine on Stick Formulation and Semi Solution Formulation with activated ADCH-Ca-Glycine* Mixture of cyclopeiitasiloxane, disteardimonium hectorite and propylene carbonate

[0068] As shown in Table 13, the presence of glycine in the formulated antiperspirant stick resulted in homogenous distribution of the antiperspirant active. 100% is a theoretical value meaning antiperspirant active is completely homogenously distributed in the stick. The higher the percentage, the more the antiperspirant active is homogenously distributed in the formulation.

[0069] Specifically, Sticks 1-3 were from different solid stick products having the same formulation composition and the same active ingredients but with different glycine level. Similarly, Semi Solution Formulations 1 and 2 were from different solid stick products having the same formulation composition and the same active ingredients but with different glycine level. The amount of chloride recovery is higher with 16.5% to 17.35% of glycine, as shown in Sticks 2 and 3 compared to Stick 1 and in Semi Solution Formulation 2 compared to Semi Solution Formulation 1.Efficacy Testing: Hot Room Test

[0070] To test the efficacy, a hot room test was performed for Example 1 and Comparative Example 1 in stick form. The investigation took place in an air-conditioned hot room at a temperature of 100 ± 2°F (37.8°C ± 1.1°C) and at 30 to 40 % relative humidity. Thirty four female panelists participated in the test.

[0071] For baseline evaluations, subjects stayed in the hot room for a warm-up period of 40 minutes. During this warm-up period, a pad was placed under each axilla to absorb sweat. Then, the axillae were dried with a soft paper towel, followed by two successive 20-minute sweat collection periods, during which pre-weighed pads were placed in each subject’s axilla by a technician. Care was taken to control factors known to influence axillary sweating, such as air movement, mental or emotional stimuli, and position of the trunk and extremities.

[0072] Day 1 (start of test phase): Randomized subjects washed their axillary vaults in a defined way at the study site before each product application. Each axilla was washed with perfume-free soap for at least 10 seconds and dried with soft, disposable towels. Then, a defined amount of the test material, i.e., 400 mg (± 25 mg) per axilla, was applied onto the axillae by a technician. To avoid absorption of the test product by clothes, the subjects stayed at room temperature until the test product was absorbed.

[0073] Days 2 to 4 (test phase): Subjects came to the study site. Subjects waited at least 10 minutes before product application. Afterwards, the subjects washed their axillae in the defined way, and the test material was applied by a technician, as described above.

[0074] Days 6 to 8 (test phase): Subjects returned to the study site about 48 hours (day 6), 72 hours (day 7) and 96 hours (day 8) after the last product application on day 4. To standardize the sweating procedure, subjects waited at least 10 minutes before entering the hot room. Afterwards, the 48, 72, and 96-hour values for antiperspirant efficacy were determined by two successive sweat collections in the hot room, as described above.

[0075] Before the sweat collection periods, the pads were weighed out in tightly capped plastic vials under standard room conditions, and all pads were stored under equal room conditions until they were applied to the test subjects. For gravimetrical determination of sweat weight, the pads were put back into the tightly capped plastic vials after the sweat collection periods, and re- weighted under standard room conditions. The difference between those two measurements represented the absorbed sweat.

[0076] The efficacy of the test product was evaluated comparing the sweat secretion between test and control product. A significance level of 0.05 (alpha) was chosen for statistical analyses.

[0077] The differences between sweat weights at baseline and 48, 72 and 96-hours after the fourth product application were used to calculate the adjusted mean and median of sweat weight ratios. Using the median change after application of the test product (Example 1 , activated ADCH-Ca-Glycine) compared to the reference product (Comparative Example 1, activated ASCH-Ca-Glycine), the percentage of sweat reduction (SR) was calculated. Wilcoxon signed rank test was performed to compare the median adjusted ratio to benchmark 1.0. The results are presented in Table 14.Table 14: Efficacy of Stick Formulation with activated ADCH-Ca-Glycine

[0078] As shown in Table 14, Example 1 had a statistically significant difference in sweat resistance compared to Comparative Example 1.

Claims

CLAIMS1. An antiperspirant active powder comprising: an activated aluminum salt; a buffering agent, wherein the buffering agent is an amino acid; and a calcium salt; wherein an HPLC peak 4 is at least 30% and an HPLC peak 5 is at least 10%, and wherein an aluminum to chlorine (A1:C1) molar ratio ranges from 0.91 to 1.25.

2. The antiperspirant active powder of claim 1, wherein the HPLC peak 4 is 85% or less.

3. The antiperspirant active powder of claim 1, wherein the HPLC peak 5 is 50% or less.

4. The antiperspirant active powder of claim 1 , wherein the aluminum salt is represented byChemical Formula 1 :[Chemical Formula 1]Al2(OH)6.aXawherein, in Chemical Formula 1 ,X is selected from the group consisting of Cl and NO3, and a ranges from 1.6 to 6.6.

5. The antiperspirant active powder of claim 1, wherein the activated aluminum salt is activated aluminum dichlorohydrate (activated ADCH).

6. The antiperspirant active powder of claim 1 , wherein the amino acid is glycine, betaine, urea, or a mixture thereof.

7. The antiperspirant active powder of claim 1, wherein the calcium salt is calcium chloride, calcium nitrate, calcium citrate, calcium carbonate, calcium hydroxide, or a mixture thereof.

8. The antiperspirant active powder of claim 1 , wherein a calcium to aluminum (Ca: Al) molar ratio ranges from 1:20 to 1:6.

9. The antiperspirant active powder of claim 1, wherein the amino acid is glycine, and wherein the calcium salt is calcium chloride.

10. The antiperspirant active powder of claim 9, wherein a glycine to aluminum (glycine: Al) molar ratio ranges from 1 : 10 to 1:1.

11. A topical composition comprising an effective amount of the antiperspirant active powder of claim 1 and a dermatologically acceptable carrier.

12. The topical composition of claim 11 in the form a liquid for a roll-on or a porous applicator, a lotion, a cream, a soft-solid stick, a solid stick, or an aerosol.

13. The topical composition of claim 11, further comprising cyclomethicone, behenyl alcohol, polypropylene glycol (PPG) 15 stearyl ether, isopropyl myristate, polyethylene, alkyl cl2-15 benzoate, hydrogenated castor oil, talc, or colloidal silica.

14. An antiperspirant active powder comprising: activated aluminum dichlorohydrate (activated ADCH); glycine; and a calcium salt; wherein an HPLC peak 4 is at least 30% and an HPLC peak 5 is at least 10%, and wherein an aluminum to chlorine (A1:C1) molar ratio ranges from 0.91 to 1.25.

15. The antiperspirant active powder of claim 14, wherein the HPLC peak 4 is 85% or less.

16. The antiperspirant active powder of claim 14, wherein the HPLC peak 5 is 50% or less.

17. The antiperspirant active powder of claim 14, wherein the calcium salt is calcium chloride, calcium nitrate, calcium citrate, calcium carbonate, calcium hydroxide, or a mixture thereof.

18. The antiperspirant active powder of claim 14, wherein a calcium to aluminum (Ca:Al) molar ratio ranges from 1:20 to 1:6.

19. The antiperspirant active powder of claim 14, wherein a glycine to aluminum (glycine:Al) molar ratio ranges from 1 : 10 to 1:1.

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