| 摘要 |
PURPOSE:To obtain a circuit board excellent in surface smoothness, heat resistance, acid resistance, fine printing accuracy and the stability of a gold electrode by forming the gold electrode onto an enamel layer composed of a metallic oxide such as La2O3, MgO, etc., main components of which respectively have weight % values within specific ranges. CONSTITUTION:A circuit substrate consists of an enamel layer made up of a metallic oxide, main components of which have the following weight %. That is, La2O3=0.5-3%, MgO=20-50%, CaO=1-25%, BaO=0-15%, B2O3=10-30%, SiO2=8-20%, MO2 (M represents at least one kind of Ti, Zr and Sn)=0-5% and P2O5 =0-5%. A gold electrode is shaped onto such an enamel layer, thus acquiring the circuit in which the upper section of a metallic base body is coated with the enamel layer, particularly a substrate, in which a fine wiring pattern is executed onto the substrate through a thick-film printing method. The substrate is excellent in surface smoothness, heat resistance, acid resistance and the stability of the gold electrode, and is proper for an electric circuit. |
