Basic aluminum antiperspirant active materials having enhanced activity,

Abstract

Disclosed are basic aluminum antiperspirant materials having univalent complex oxoanions (e.g., nitrate); methods of making such materials; antiperspirant compositions containing such basic aluminum materials, another antiperspirant active material (e.g., a basic zirconium halide salt), and optionally a neutral amino acid; and methods of making such compositions. Size exclusion high performance liquid chromatography chromatograms of the disclosed basic aluminum materials have a peak 4 relative area of at least 25%, a peak 3 relative area of less than 60%, the sum of the peaks 3 and 4 being at least 50%; and less than 10% of the chromatographic peaks eluting at peaks 1 and 2. The disclosed basic aluminum materials have less than 25% of the aluminum in the form of Al.sup.b polyhydroxyaquoaluminum, and have a .sup.27 Al NMR spectrum in which the area of the 71.5-73.5 ppm resonance line includes more than 50% of the combined areas of the 62.5-63.5 ppm and 71.5-73.5 ppm resonance lines, and 5%-30% of the total area under the spectrum from 140 ppm to -80 ppm is contained in the resonance line at 71.5-73.5 ppm. The basic aluminum material of the present invention can be produced by adding a stoichiometric or near-stoichiometric amount of aluminum metal to a solution of an aluminum salt having a univalent complex oxoanion; the basic aluminum material can also be made by adding to such solution of the aluminum salt, aluminum metal having, in total, a relatively small surface area (large-sized particles of aluminum).