Antiperspirant active compositions and manufacture thereof

Abstract

An antiperspirant active composition comprising an aluminum salt, the aluminum salt (i) having an aluminum to chloride molar ratio of 0.3:1 to 3:1; and (ii) having a species of polyhydroxyoxoaluminum cation detectable at 76 ppm by 27Al NMR that is present in a relative abundance on a 27Al NMR spectrograph that is greater than any other polyhydroxyoxoaluminum cation detectable by 27Al NMR. Also, disclosed are methods of making the antiperspirant active.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority to U.S. Provisional Application No. 61 / 479,069, filed on 26 Apr. 2011, which is incorporated herein by reference.FIELD OF THE INVENTION[0002]The invention relates to antiperspirant active compositions comprising an aluminum salt and to methods of making an antiperspirant active composition.BACKGROUND OF THE INVENTION[0003]Antiperspirant salts, such as aluminum chlorohydrex (also called aluminum chlorohydrex polymeric salts and abbreviated here as “ACH”) and aluminum zirconium glycine salts (abbreviated here as “ZAG”, “ZAG complexes” or “AZG”), are known to contain a variety of polymeric and oligomeric species with molecular weights (MW) of 100 Da-500,000 Da. It has been clinically shown that, in general, the smaller the species, the higher the efficacy for reducing sweat.[0004]In an attempt to increase the quality and quantity of smaller aluminum and / or zirconium species, a number of efforts have focused o...

AI Technical Summary

Benefits of technology

The present invention is based on modifying the composition of an antiperspirant salt by heating it in an aqueous solution containing a first aluminum salt, an inorganic salt, and a buffer. The heating process results in the formation of a new species of polyhydroxyoxoaluminum cation that is detectable in a 27Al NMR spectrum. The new species is present in an amount that is at least 76% of the total polyhydroxyoxoaluminum cations detectable in the spectrum. The heating process can be carried out at temperatures between 100°C and 70°C for at least 10 days. The resulting antiperspirant active composition has a unique composition that makes it different from other antiperspirant compositions.

Problems solved by technology

It is known that 27Al NMR spectroscopy may not fully elucidate the chemical composition of a partially neutralized Al salt solution, since there may be a variety of Al species that do not give rise to sharp and unambiguous resonance peaks.

The small quantities obtained, lack of purity, and lack of method of making has prevented science from isolating this polycation in sufficient quantity and purity so that its structure could be determined.

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