US 12,448,319 B2
Alkali-free glass
Hirofumi Tokunaga, Tokyo (JP); and Kazutaka Ono, Tokyo (JP)
Assigned to AGC Inc., Tokyo (JP)
Filed by AGC Inc., Tokyo (JP)
Filed on Aug. 6, 2021, as Appl. No. 17/396,217.
Application 17/396,217 is a continuation of application No. PCT/JP2020/004847, filed on Feb. 7, 2020.
Claims priority of application No. 2019-020257 (JP), filed on Feb. 7, 2019; application No. 2019-051570 (JP), filed on Mar. 19, 2019; application No. 2019-141422 (JP), filed on Jul. 31, 2019; and application No. 2019-186805 (JP), filed on Oct. 10, 2019.
Prior Publication US 2021/0363051 A1, Nov. 25, 2021
Int. Cl. C03C 3/091 (2006.01); C03C 3/087 (2006.01)
CPC C03C 3/091 (2013.01) [C03C 3/087 (2013.01)] 52 Claims
 
1. An alkali-free glass, comprising:
an alkali-free glass having a composition comprising, in mol % in terms of oxides, 63 to 69% of SiO2, 8 to 13% of Al2O3, 0.5 to 4% of B2O3, 8 to 15% of MgO, 4 to 12% of CaO, 0 to 4.5% of SrO, and 0 to 0.1% of BaO,
wherein [MgO]/[CaO] is in a range of 0.67 to 3.75,
a value of Formula (A), 0.642[SiO2]+1.459[Al2O3]−0.166[B2O3]+1.642[MgO]+1.280[CaO]+0.965[SrO]+0.473[BaO], is 86 or larger,
a value of Formula (B), 7.667[SiO2]+11.721[Al2O3;]−2.138[B2O3]+3.343[MgO]+3.090[CaO]+2.487[SrO]+3.658[BaO]−10, is 715 or smaller,
a value of Formula (C), −14.18[SiO2]+58.31[Al2O3;]+6.76[B2O3]+8.35[MgO]+38.73[CaO]+23.06[SrO]+15.95[BaO], is 200 or smaller, and
a value of Formula (D), −0.754[SiO2]−0.754[SiO2]+1.651[Al2O3]−0.112[B2O3]+1.856[MgO]+3.316[CaO]+3.968[SrO]+1.682[BaO]+(−3.275[MgO][CaO]−1.661[MgO][SrO]+1.801[MgO][BaO]+4.952[CaO][SrO]+2.401[CaO][BaO]+1.110[SrO][BaO])/([MgO]1.110[SrO][BaO])/([MgO]+[CaO]+[SrO]+[BaO]), is 14.5 or smaller.