| 摘要 |
PROBLEM TO BE SOLVED: To obtain a fire resistant dense sealing material less liable to soften or melt at high temp., excellent in adhesiveness, less liable to shrink and capable of preventing a leak of air and gas by blending magnesia stock with zircon stock, sodium phosphate and boric acid in a specified ratio. SOLUTION: This fire resistant sealing material is obtd. by blending 5-35 pts.wt. magnesia stock with 50-90 pts.wt. zircon stock, 3-15 pts.wt. sodium phosphate and 0.1-2 pts.wt. boric acid. Seawater magnesia or other magnesia is used as the magnesia stock and the particle diameter is preferably about 500μm. Commercially available zircon sand or zircon flour may be used as the zircon stock. The sodium phosphate to be used is not especially limited but sodium hexametaphosphate having satisfactory deflocculating property is preferably used. The boric acid to be used is not especially limited but the particle diameter is preferably about 250μm. |
