... Sodium Tripolyphosphate(STPP/FCC IV)Properties: White microdot powder with luster, melting point at 622Deg. C, easily soluble in water, with remarkable chelating ... wash, soap synergistic agent, water softener, leather pre-tanning agent, dye auxiliary agent, and dispersant of ... magnesium oxide, calcium carbonate drilling mud, preservative agent for paper making, organic synthesis catalyzer, and ...