... STPP, Sodium Tripolyphosphate Used as main auxiliary of synthetic wash, soap synergistic agent, water softener, etc. Specification:NA5P3O10P2O5INSOLUBLE IN WATERPH 1% AQUEOUS SOLUTIONLOSS ... as Ca2+, Mg2+, can soften hard water, change suspension into solution, slightly alkaline, without causticity. Application: Used as main auxiliary ... moisture, do not pile up in the open air. Sodium Tripolyphosphate