Crystalline glass composition for use in circuit board, sintered crystalline glass, insulator composition insulating paste and thick film circuit board

Abstract

Provided is a crystalline glass composition for use in a circuit board that can be sintered at a temperature of 1100° C. and is endowed with favorable characteristics such as a relative dielectric constant of as low as ½ and a thermal expansion coefficient of as high as 12 ppm/° C. as an electrical insulating insulator for use in a circuit board. The crystalline glass composition contains SiO2, MgO and CaO, the composition ratio of SiO2, MgO and CaO in % by weight falling within an area surrounded by the lines connecting the points A (25, 45, 30), B (25, 0, 75), C (44, 0, 56), D (44, 22, 34), E (40, 19, 41) and F (29, 40, 31) in a ternary phase diagram wherein at least one melwinite, monticellite or calcium silicate crystalline phase is deposited by heat-treating the composition. A ceramic powder having a thermal expansion coefficient of about 6.0 ppm/C or more is sometimes added in the powder comprising the glass composition.

Dependencies are inferred from the claim text.