Patent ID: 8147810

Claim:
A method of making an antiperspirant active composition comprising: I) heating an aqueous solution containing an aluminum salt having an aluminum to chloride molar ratio of about 0.3:1 to about 3:1, optionally with a buffer agent, at a temperature of about 50° C. to about 100° C. to reflux for a period of time of about 1 hour to about 6 hours to obtain an aluminum salt solution; II) adding an aqueous solution of sodium hydroxide to obtain an aluminum salt solution having an OH:Al molar ratio of about 2:1 to about 2.6:1 to obtain a pH adjusted aluminum salt solution having a pH of about 2 to about 5; III) providing a calcium ion to the solution; and IV) optionally adding an aqueous solution containing a zirconium compound to the pH adjusted aluminum salt solution to thereby obtain an aluminum-zirconium salt solution having a molar ratio of aluminum to zirconium of about 5:1 to about 10:1, wherein when the calcium ion source is a base, the weight ratio of sodium hydroxide to calcium base is greater than 0 to about 20; or when the calcium ion source is a salt, the weight ratio of sodium hydroxide to calcium ion is greater than 0 to about 11.