| 摘要 |
1,269,857. Refractories. QUIGLEY CO. Inc. 29 Oct., 1969, No. 53064/69. Heading C1J. A binder for refractories consists of Na 2 SiO 3 and NH 4 pentaborate in a weight ratio of 0À2- 5À0 to 1. The Na 2 O: SiO 2 ratio is 1 : ¢-4. Specified refractories are chrome ore, MgO, ZrO 2 , ZrSiO 4 , Al 2 O 3 , mullite, kyanite or any of their mixtures. |
