| 摘要 |
The present invention relates to a non-alkali glass having a strain point of from 710°C to lower than 725°C, an average thermal expansion coefficient at from 50 to 300°C of from 30×10 -7 to 43×10 -7 /°C, a temperature T 2 at which glass viscosity reaches 10 2 dPa·s of 1710°C or lower, a temperature T 4 at which the glass viscosity reaches 10 4 dPa·s of 1320°C or lower, and containing, indicated by mol% on the basis of oxides, SiO 2 66 to 70, Al 2 O 3 12 to 14, B 2 O 3 exceeding 0 to 1.5, MgO exceeding 9.5 to 13 (or 5 to 9.5), CaO 4 to 9 (or 4 to 11), SrO 0.5 to 4.5, BaO 0 to 0.5 and ZrO 0 to 2, in which MgO+CaO+SrO+BaO is from 17 to 21 (or exceeding 18.2 to 21), MgO/(MgO+CaO+SrO+BaO) is 0.4 or more (or 0.25 or more), MgO/(MgO+CaO) is 0.4 or more (or 0.3 or more), and MgO/(MgO+SrO) is 0.6 or more (and Al 2 O 3 ×(MgO/(MgO+CaO+SrO+BaO)) is 5.5 or more). |
