Used primarily as a flame retardant synergist, especially in combination with halogenated compounds. It enhances the fire resistance of plastics, textiles, rubber, and coatings by reducing flammability and slowing the spread of fire. Commonly found in electronic devices, automotive components, and building materials to meet safety standards. Also utilized in the production of colored glass and ceramics to improve clarity and reduce discoloration. In some applications, it acts as a catalyst in the manufacturing of polyester materials.