| 摘要 |
PURPOSE:To enable a heat generated by a heat generating resistor to be efficiently transferred to a recording paper, by providing an air-containing heat- insulating layer on the surface of an insulating substrate. CONSTITUTION:For example, an alumina ceramic substrate 2 is heated, a glass 1 provided with air bubbles by blowing air into the glass in a molten state is cast on the substrate 2, then a plate 3 not wettable with the molten glass is placed thereon, and the molten glass is cooled while pressing the plate 3 against it with a fixed force. By this method, a glass layer having a flat surface and containing foams therein can be obtained. A protective layer 4, electrodes 5 and heat generating elements 6 are provided on the glass layer. Accordingly, since a heat-insulating layer having a low thermal conductivity, a low specific heat, excellent mechanical strength and favorable heat resistance is provided beneath a heat generating resistor, the heat generated by the heating elements can be prevented from escaping to the substrate side, and a thermal head having a high thermal efficiency can be produced. |
