Method of making high performance activated aluminum sesquichlorohydrate powders
Activated aluminum sesquichlorohydrate (AASCH) powders and method of making are disclosed. The AASCH powder has Al:Cl atomic ratio of from about 1.60 to about 1.90 and Band III polymer concentration of at least about 20% and Band IV polymer concentration of at least about 15% when analyzed with Size Exclusion Chromatogram (SEC) operated by High Performance Liquid Chromatograph (HPLC). The method of making the active comprises (a) diluting the concentrated aluminum sesquichlorohydrate (ASCH) solution to from about 10% to about 25% by weight and (b) heating the diluted solution to obtain a Band III polymer concentration of at least about 20% and a Band IV polymer concentration of at least about 15%, and (c) drying the heated solution to powders having Al:Cl ratio of about 1.60 to about 1.90 and (d) optionally screen or light mill the powders to free flowing spherical particles.
1. A method of making activated aluminum sesquichlorohydrate (AASCH) powders consisting of:
(a) diluting a concentrated aluminum sesquichlorohydrate (ASCH) solution to about 1% to about 25% by weight,
(b) heating the diluted solution to activate the solution,
(c) drying the activated solution to form the activated aluminum sesquichlorohydrate (AASCH) powders,
(d) optionally adding a buffering agent prior to the drying, and
(e) optionally sieving or milling the AASCH powders,
wherein the activated AASCH powders have an Al:Cl ratio of from about 1.60 to about 1.90, a Band III polymer concentration of at least 20%, and a Band IV polymer concentration of at least 15%,
wherein no acid or acidic aluminum chloride is introduced after the heating of the diluted solution.
2. The method of claim 1 , wherein the Al:Cl ratio is from about 1.7 to about 1.8.
3. The method of claim 1 , wherein the Band III polymer concentration is at least 40% and the Band IV polymer concentration is at least 20%.
4. The method of claim 1 , wherein the buffering agent is selected from the group consisting of amino acid, alkaline glycinate, alkaline earth glycinate, zinc glycinate, strontium glycinate, and mixtures thereof.
5. The method of claim 1 , wherein the buffering agent is selected from the group consisting of glycine, betaine, urea and mixtures thereof.
6. The method of claim 1 , wherein the diluted solution is heated to about 85° C. to about 105° C. for at least 30 minutes.
7. The method of claim 1 , wherein the diluting of the concentrated sesquichlorohydrate (ASCH) solution includes adding a solvent.
8. The method of claim 1 , wherein the concentrated ASCH solution has a Band I polymer concentration of less than 5% and Band III polymer concentration of at least 20%.
9. The method of claim 1 , wherein the concentrated ASCH solution has an Al:Cl ratio ranging from about 1.5 to about 1.9.
10. The method of claim 1 , wherein the sieved or milled AASCH powders have a particle size ranging from about 1 micron to about 200 microns.
11. The method of claim 1 , wherein the Band I polymer concentration is less than 1%.
12. The method of claim 1 , wherein the AASCH powders are substantially free of zirconium.
13. The method of claim 1 , wherein the drying is spray drying.
14. The method of claim 1 , wherein the AASCH powders have at least 5% of Al 30 .
15. The method of claim 1 , wherein the AASCH powders have less than 10% of Al 13 .
16. The method of claim 1 , wherein the AASCH powders have a moisture content ratio ranging from about 2% to about 15%.
17. The method of claim 1 , wherein the AASCH powders have a pH ranging from about 3.0 to about 4.5.