Sodium Tripolyphosphate (STPP) - Lite

Sodium triphosphate (STP, sometimes STPP or sodium tripolyphosphate or TPP) is an inorganic compound with formula Na5P3O10. It is the sodium salt of the polyphosphate penta-anion, which is the conjugate base of triphosphoric acid.It is produced on a large scale as a component of many domestic and industrial products, especially detergents.


  • The majority of STPP is consumed as a component of commercial detergents. It serves as a "builder", industrial jargon for a water softener. In hard water (water that contains high concentrations of Mg2+ and Ca2+), detergents are deactivated. Being a highly charged chelating agent, TPP5- binds to dications tightly and prevents them from interfering with the sulfonate detergent.
  • STPP is a preservative for seafood, meats, poultry, and animal feeds. It is common in food production as E number E451. In foods, STPP is used to retain moisture.

Sodium Tripolyphosphate (MSDS) (2,19 MB)