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US 2026/0070834 A1Published application
Alkali-free glass sheet
AssigneeNippon Electric Glass Co., Ltd.
InventorMayu NISHIMIYA
Life of this patent
Estimating the term…
Abstract
An alkali-free glass sheet according to the present invention contains, as a glass composition, in mol %, from 60% to 80% of SiO2, from 12% to 15% of Al2O3, from 1.2% to 4% of B2O3, from 0% to 0.5% of Li2O+Na2O+K2O, from 2% to 8% of MgO, from 2% to 11% of CaO, from 0% to 5% of SrO, from 0% to 5% of BaO, and from 10% to 16% of MgO+CaO+SrO+BaO, in which a mol % ratio B2O3/Al2O3 is from 0.1 to 0.3, a mol % ratio (B2O3+BaO)/SiO2 is from 0.01 to 0.1, and MgO+CaO+SrO+BaO—Al2O3 is from −2% to +2%.
Claims13
1:
- An alkali-free glass sheet comprising, as a glass composition, in mol %, from 60% to 80% of SiO2, from 12% to 15% of Al2O3, from 1.2% to 4% of B2O3, from 0% to 0.5% of Li2O+Na2O+K2O, from 2% to 8% of MgO, from 2% to 11% of CaO, from 0% to 5% of SrO, from 0% to 5% of BaO, and from 10% to 16% of MgO+CaO+SrO+BaO, wherein a mol % ratio B2O3/Al2O3 is from 0.1 to 0.3, a mol % ratio (B2O3+BaO)/SiO2 is from 0.01 to 0.1, and (MgO+CaO+SrO+BaO—Al2O3) is from −2% to +2%.
2:
- An alkali-free glass sheet comprising, as a glass composition, in mol %, from 65% to 75% of SiO2, from 12.5% to 14% of Al2O3, from 1.5% to 4% of B2O3, from 0% to 0.1% of Li2O+Na2O+K2O, from 3.3% to 7% of MgO, from 2% to 11% of CaO, from 0% to 5% of SrO, from 0% to 5% of BaO, and from 10% to 16% of MgO+CaO+SrO+BaO, wherein a mol % ratio B2O3/Al2O3 is from 0.12 to 0.19, a mol % ratio (B2O3+BaO)/SiO2 is from 0.02 to 0.07, and (MgO+CaO+SrO+BaO—Al2O3) is from −2% to +1.2%.
3:
- The alkali-free glass sheet according to claim 1, wherein the content of B2O3 is from 2 mol % to 3 mol %.
4:
- The alkali-free glass sheet according to claim 1, wherein the glass composition does not substantially contain As2O3 and Sb2O3, and further contains from 0.001 mol % to 1 mol % of SnO2.
5:
- The alkali-free glass sheet according to claim 1, wherein a Young's modulus is 80 GPa or more, a strain point is 720° C. or higher, and a liquidus temperature is 1400° C. or lower.
6:
- The alkali-free glass sheet according to claim 1, wherein a strain point is 730° C. or higher.
7:
- The alkali-free glass sheet according to claim 1, wherein a Young's modulus is more than 82 GPa.
8:
- The alkali-free glass sheet according to claim 1, wherein a specific Young's modulus is 31.5 GPa/g·cm−3 or more.
9:
- The alkali-free glass sheet according to claim 1, wherein an average thermal expansion coefficient in a temperature range of from 30° C. to 380° C. is from 20×10−7/° C. to 50×10−7/° C.
10:
- The alkali-free glass sheet according to claim 1, wherein an annealing point is 800° C. or higher.
11:
- The alkali-free glass sheet according to claim 1, wherein a liquidus viscosity is 103.5 dPa·s or more.
12:
- The alkali-free glass sheet according to claim 1, which is for use in an organic EL device.
13:
- The alkali-free glass sheet according to claim 1, which is for use in a magnetic recording medium.