| abstract |
Basic aluminum antiperspirant materials of the formula Al2(OH)6-a Xa where 0.5</=a</=5 and X is a univalent oxyanion of nitrogen or halogen eg NO3<->, CIO4<->, CIO3<-> or IO4<->, where (i) 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; (ii) the basic aluminum materials have less than 25% of the aluminum in the form of Al<b> polyhydroxyaquoaluminum, and (iii) have a <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). |