... Ba, Mg, Cu and Fe; it is a fine agent for water treatment. 2>Sodium Hexametaphosphate's Technical Specifications: No. ... c) it is mainly used as a water softening agent in solution for printing, dyeing, and boiler; Diffusant in papermaking; ... slow corrodent, floating agent, dispersing medium, high temperature agglomerant, detergent and soil analytical chemistry reagent. For food grade.4> Sodium ...