| 摘要 |
PROBLEM TO BE SOLVED: To provide a glass for chemical tempering hardly being broken even though being damaged.SOLUTION: The present invention relates to a glass for chemical tempering containing, by molar percentage based on following oxide, SiOof 56 to 69%, AlOof 8 to 16%, NaO of 9 to 22%, KO of 0 to 1%, MgO of 7 to 14%, ZrOof 0 to 1%, BOof 0 to 6% with Z calculated by following formula using molar percentage content of each element of SiO, AlO, NaO, MgO, BOand KO of 870 or more. Z=2×SiO+55×AlO+22×NaO+15×MgO-30×BO-126×KO.SELECTED DRAWING: Figure 1 |
