Antiperspirant activity of basic aluminum compounds

Process for improving the antiperspirant activity of a basic aluminum compound consisting essentially of a complex having the empirical formula:

• Al.sub.2 (OH).sub.6-a X.sub.a nH.sub.2 O
• where X is Cl, Br or I, and a is about 0.3 to about 4, and n is about 0.5 to about 8, comprising the steps of:
• (i) heating an aqueous liquid solution containing the basic aluminum compound at an aluminum concentration of 2.5 to 8.5% by weight of the solution at a temperature of 50.degree. to 140.degree. C. for a period of time sufficient to impart to said basic aluminum compound the property of:
• (a) having a Size Exclusion Chromatography Test Band having a relative retention time corresponding to Band III of the Standard Basic Aluminum Chloride Solution Size Exclusion Chromatogram;
• and
• (b) having a Band III Percent Aluminum Value of at least 20 percent;
• and
• (ii) drying the aqueous liquid to give a basic aluminum compound having enhanced anti-perspirant activity and substantially the same empirical formula as the basic aluminum compound in the aqueous liquid solution prior to said heating in the form of a hydrated water-soluble powder retaining the property of:
• (a) having a Size Exclusion Chromatography Test Band having a relative retention time corresponding to Band III of the Standard Basic Aluminum Chloride Solution size Exclusion Chromatogram;
• and
• (b) having a Band III Percent Aluminum Value of at least 20 percent.