| abstract |
An alkali-free glass substrate which exhibits a high Young's modulus, a low coefficient of linear expansion, a high strain point, a low density, and a low viscosity and which is freed from the devitrification in float forming and is excellent in acid resistance. An alkali-free glass substrate which is substantially free from alkalis and BaO and comprises by mole SiO2: 57.0 to 65.0%, Al2O3: 10.0 to 12.0%, B2O3: 6.0 to 9.0%, MgO: 5.0 to 10.0%, CaO: 5.0 to 10.0%, and SrO: 2.5 to 5.5% based on the oxides and which satisfies the relationships: MgO + CaO + SrO = 16.0 to 19.0%, MgO/(MgO + CaO + SrO) ≥ 0.40, and B2O3/(SiO2 + Al2O3 + B2O3) ≤ 0.12 and exhibits a Young's modulus of 75GPa or above, a coefficient of linear expansion at 50 to 350 DEG C of 30 x 10<SP>-7</SP> to 40 x10<SP>-7</SP>. |