A PARTICLE OF MAGNESIUM HYDROXIDE FOR FLAME RETARDANT AND THE METHOD FOR MANUFACTURING THE SAME, THE METHOD FOR SURFACE TREATING THE PARTICLE OF MAGNESIUM HYDROXIDE

摘要

Magnesium hydroxide particles for a flame retardant are provided to be improved in flame retardancy through proper surface treatment of magnesium hydroxide even without performing hydrothermal treatment, and to be produced at a low cost. Magnesium hydroxide particles for a flame retardant having a polyhedral crystal shape have a particle size of 0.2-5.0 micron, an average particle size of 1.0-1.5 micron, and a specific surface area of 3-8 m^2/g, and are produced by hydration of magnesium oxide. A method for preparing the magnesium hydroxide particles includes the steps of: grinding magnesium oxide into powder having a particle size of 325 mesh or smaller; and mixing the magnesium oxide powder with water to obtain a mixed solution, and adding an inorganic acid or magnesium salt to the mixed solution to perform hydration. Further, the magnesium oxide is heat-treated at a firing temperature of 1500°C or more and a chemical purity is 97 wt.% or more.