| 摘要 |
PURPOSE:To obtain the title crystallized glass having excellent mechanical strength and durability, exhibiting a sufficient aesthetic property when applied as the dental material, and having high transparency by incorporating a P oxide and an Mg oxide into the glass in a specified molar ratio, respectively expressed in terms of P2O5 and MgO. CONSTITUTION:The crystallized glass for dental material of this invention contains 45-70mol.% P oxide, expressed in terms of P2O5, and 30-55mol.% Mg oxide, expressed in terms of MgO. The phosphates of orthophosphoric acid, for example, are used as the raw material of P for the production of the crystallized glass, and MgO, for example, is used as the raw material of Mg. The specified weights of the materials are mixed, and the mixture is baked at 200-900 deg.C for 1-10hr to obtain the raw crystallized glass material. The obtained raw crystallized glass material is heated at 900-1,500 deg.C for 5min-10hr in a platinum crucible, melted, and homogeneously vitrified to obtain the desired crystallized glass for dental material. |
