| 摘要 |
PROBLEM TO BE SOLVED: To provide a dental ceramic material suitable for manufacturing a tooth crown using a ceramic core, and having a low firing temperature, a low expansion factor and high chemical durability. SOLUTION: In a glass containing, as main components, a silicon oxide, an aluminum oxide, a boron oxide, a zinc oxide, a sodium oxide, and a lithium oxide, expressed in wt.% against the total when converted into SiO2, Al2O2, B2O3, ZnO, Na2O and Li2O, the contents of these components are respectively SiO2: 57 to 67 wt.%, AlO2: 8 to 18 wt.%, B2O2: 15 to 25 wt.%, ZnO: 0.1 to 2 wt.%, Na2O: 3 to 7 wt.%, and Li2O: 2 to 8 wt.%. Especially, the thermal expansion factor of the glass is 6.0×10-6 (1/ deg.C) or lower. |
