... water ≤ (%)1.0ZnO (%)37-40B2O3 (%)45.0-48.0Loss on ignition (%)13.5-15.5Specific gravity (g/cm3)2.67Melting ... most common used grade. It has owned some excellent properties on non-toxicity, slight solubility in water, good thermal stability, ... performance, remove smoke emission and adjust the balance on chemical, mechanical, electrical etc properties.2. As environmental protection substitute to ...