CRYSTALLIZED GLASS COMPOSITION FOR CIRCUIT BOARD, CRYSTALLIZED GLASS SINTERED BODY, INSULATOR COMPOSITION, INSULATING PASTE AND THICK FILM CIRCUIT BOARD

摘要

PURPOSE: A crystallized glass composition is to have a property suitable for electric insulating material for circuit board, which is sinterable below the temperature of 1100 deg.C and has a specific dielectricity of less than 12 and a thermal expansion coefficient of more than 12 ppm/deg.C. CONSTITUTION: A glass composition comprises SiO2, MgO and CaO whose composition ratio expressed in weight percent lies in an area surrounded by a line connecting a point A(25,45,30), a point B(25,0,75) a point C(44,0,56) a point D(44,22,34) a point E(40,19,41) and a point F(29,40,31) in a ternary phase diagram thereof. By heat treating the composition, at least one species of crystalline phase of melwinite(Ca3MgSi2O8), monticellite(CaMgSiO4) and calcium silicate(at least one of CaSiO3, Ca3Si2O7, Ca2SiO4 and Ca3SiO5) is deposited. A ceramic composition having a thermal expansion coefficient of more than 6.0 ppm/deg.C is added to the powder composed of the glass composition.