According to a new patent application, many antiperspirants have been designed to help reduce sweat. In most cases, the actives used are aluminum and zirconium hydroxide compounds, complexes and their derivatives. While these actives are generally effective, alternatives are sought.
Tin (II) fluoride, also known as stannous fluoride (SnFa), is soluble in water but oxidizes to form insoluble precipitates of tin. In addition, tin can form compounds with phosphates.
Thus, according to these inventors, there is still a need to stabilize tin (II) compounds, such as tin (II) fluoride and tin (II) chloride, to make them effective in personal care. Embodiments of this invention are designed to meet these needs.
WIPO Patent Application WO/2017/117301
Publication date: July 6, 2017
Described in this patent are water-soluble tin phosphate complexes formed from tin (II) fluoride or tin (II) chloride and a tripolyphosphate salt, e.g., sodium tripolyphosphate (Na5P3O10), and personal care compositions comprising the complexes.
The inventors discovered that tin (II) fluoride and chloride form complexes upon mixing with said salt and, without being bound by theory, these complexes are believed, when contacted with sweat-simulating proteins, to form a white precipitate that may be an appropriate occlusive active for wetness control. This is due to its ability to form plug that can physically inhibit sweat from skin.