It is anhydrous zinc borate (2ZnO3B2O3), without crystal water, has a higher thermal decomposition temperature and a weight loss of less than 1.5% at 400℃; It can still remain stable at 600℃. As a flame retardant and smoke suppressant, anhydrous zinc borate can be used in high temperature nylon, polyester, polyether ketone, polysulfone and fluoropolymer polymer with high processing temperature requirements.