Antiperspirant compositions based on titanium salts

Antiperspirant compositions have traditionally relied upon aluminium-based active compounds to reduce sweating. Titanium is a physiologically inert metal, and titanium metal chelates appear to induce superficial physical pore blockage to provide effective antiperspirancy in a variety of product types. Titanium metal chelates can be formed from titanium alkoxides and organic acids. Conflicting opinions as to the salt structure exist and, in the case of part-neutralized ammonium titanium lactate (ATL) salt, evidence has been seen for a range of ligands bound to different strengths at different stages of hydrolysis. Aluminium is thought to work by ductal diffusion to give antiperspirancy via neutralization to a polymeric, relatively superficial gel obstruction. ATL mimics conventional alumiunium salts in that it is mainly a topical antiperspirant active, with ATL-treated skin restored to normal patterns of sweating activity after a few tape-strips. Under acidic and near-neutral pH conditions, the ATL active is relatively stable to hydrolysis and can be formulated into topical compositions as either an aqueous solution of the active or as a free-flowing powder in anhydrous systems. When judged by an in vitro efficacy technique which is thought to predict in vivo performance, ATL functions as an effective antiperspirant.