초록

Glass fibers having suitable properties for reinforcing electrical laminates have a defined viscosity-liquidus relationship, a low coefficient of thermal expansion, a high elastic modulus, and a low dielectric constant.

대표청구항 ▼

A magnesia boroaluminosilicate glass fiber consisting essentially of, in approximate weight percent, 50-65% by weight SiO2, 10-25% Al2O3, 5-15% B2O3 and less than 15% MgO, said glass fiber optionally including less than 5% TiO2 and less than 5% ZnO, the weight ratio of Al2O3/MgO being from 2.0 to 2.

A magnesia boroaluminosilicate glass fiber consisting essentially of, in approximate weight percent, 50-65% by weight SiO2, 10-25% Al2O3, 5-15% B2O3 and less than 15% MgO, said glass fiber optionally including less than 5% TiO2 and less than 5% ZnO, the weight ratio of Al2O3/MgO being from 2.0 to 2.5, the composition being selected such that said glass fiber has a coefficient of thermal expansion of from about 1 to about 2.3 (ppm/K), an elastic modulus greater than about 10 (M psi), a dielectric constant of less than about 6, a viscosity (in poise) of 10 to the 2.5 power at a temperature between about 2790°F. and about 2830°F., and a liquidus temperature between about 2300°F. to about 2500°F., the liquidus temperature being 300°F. or more below the temperature at which glass has viscosity of 102.5 poise. A laminate comprising the magnesia boroaluminosilicate glass fiber defined in claim 1. The laminate of claim 2 in combination with a ceramic chip and forming an integrated circuit.