| 摘要 |
PURPOSE:To prevent reaction between a mold material and molten glass and to obtain a molded body contg. no foam or foreign matter with high dimensional accuracy in the process for casting melt of calcium phosphate glass in a mold and cooling, by specifying the mold material. CONSTITUTION:Melt contg. >=90wt% calcium phosphate is casted in a mold consisting of a mold material contg. 1-90wt% BN and solidified by cooling. When the content of BN is <1wt%, the effect for reducing wettability by the mold material is insufficient. If the content of BN is >90wt%, the strength of the mold is decreased and the mold is easily broken during molding due to the insufficiency of the proportion of binder. Removal of BN from the mold is also caused during molding and removed BN is liable to mix with the glass. The kind of the binder for the mold material is not limited, but phosphate, silicate and gypsum are preferred because of providing a mold having high strength and resulting desirable operability such as requirement of appropriate hardening time, etc. |
