Patent ID: 11565966

Abstract:
Provided is a glass composition for glass fiber having a low dielectric constant and a low dielectric loss tangent, suppressing occurrence of phase separation, and reducing viscosity at high temperatures. The glass composition for glass fiber includes: SiO2 in the range of 52.0 to 59.5% by mass; B2O3 in the range of 17.5 to 25.5% by mass; Al2O3 in the range of 9.0 to 14.0% by mass; SrO in the range of 0.5 to 6.0% by mass; MgO in the range of 1.0 to 5.0% by mass; and CaO in the range of 1.0 to 5.0% by mass, and includes F2 and Cl2 in the range of 0.1 to 2.5% by mass in total, with respect to the total amount.