Process of manufacture of an antiperspirant composition
A process for manufacture of an antiperspirant composition comprising the reaction of an aqueous solution of aluminum sesquichlorohydrate, water soluble calcium salt and amino acid, at a total anhydrous solids content of from 33 to 60% by weight and at a temperature of at least 65° C., for a period of from 1 to 24 hours, wherein the molar ratio of water soluble calcium salt to aluminum sesquichlorohydrate is at least 1:40 and the molar ratio of amino acid to aluminum sesquichlorohydrate is at least 1:20, the mixture then being cooled to less than 25° C. and diluted with at least an equal weight of water or to a total anhydrous solids content of less than 31% by weight, the dilution phase being performed within 10 days of cooling phase.
1. A process for manufacture of an antiperspirant composition comprising the reaction of an aqueous solution of aluminium sesquichlorohydrate, water soluble calcium salt and amino acid, at a total anhydrous solids content of from 33 to 60% by weight and at a temperature of at least 65° C., for a period of from 1 to 24 hours, wherein the molar ratio of water soluble calcium salt to aluminium sesquichlorohydrate is at least 1:40 and the molar ratio of amino acid to aluminium sesquichlorohydrate is at least 1:20, the mixture then being subjected to a cooling phase in which it is cooled to less than 25° C. and a dilution phase in which it is diluted to a total anhydrous solids content of less than 25% by weight, the dilution phase being performed within 10 days of cooling phase.
2. The process according to claim 1 , wherein the aluminium sesquichlorohydrate is of formula Al 2 (OH) 4.4 Cl 1.6 to Al 2 (OH) 4.9 Cl 1.1 .
3. The process according to claim 1 , wherein the molar ratio of water soluble calcium salt to aluminium sesquichlorohydrate is at least 1:20 and the molar ratio of amino acid to aluminium sesquichlorohydrate is at least 1:10.
4. The process according to claim 1 , the reaction of the aqueous solution of aluminium sesquichlorohydrate, water soluble calcium salt and amino acid is continued until a Band III content of at least 40% is achieved.
5. The process according to claim 1 , wherein in the cooling phase the mixture is cooled to less than 25° C. at a rate of at least 0.9° C. per minute.
6. The process according to claim 1 , wherein the mixture is still at a temperature of at least 65° C. when the dilution phase is commenced.
7. The process according to claim 6 , wherein the temperature of the water used for the dilution is no greater than 20° C. less than the temperature of the mixture to which it is added.
8. The process according to claim 7 , wherein the temperature of the water used for the dilution is no greater than 10° C. less than the temperature of the mixture to which it is added.
9. The process according to claim 1 , wherein the dilution phase is performed within 5 days of the cooling phase.
10. The process according to claim 1 , wherein the activation process is performed at an anhydrous solids level of at least 40% by weight.
11. The process according to claim 1 , wherein the dilution is carried out within 7 days of the cooling phase.
12. An aqueous antiperspirant composition prepared according to claim 1 .
13. An aqueous antiperspirant composition prepared according to claim 10 .
14. A cosmetic method of attaining an antiperspirancy benefit comprising the topical application of a composition according to claim 11 the surface of the human body.
15. The process according to claim 1 wherein the aluminium sesquichlorohydrate is of formula Al 2 (OH) 4.7 Cl 1.3 to Al 2 (OH) 4.9 Cl 1.1 .
16. The process according to claim 1 wherein the reaction of the aqueous solution of aluminium sesquichlorohydrate, water soluble calcium salt and amino acid is continued until a Band III content of at least 50% is achieved.
17. The process according to claim 1 wherein the reaction of the aqueous solution of aluminium sesquichlorohydrate, water soluble calcium salt and amino acid is continued until a Band III content of at least 60% is achieved.