Thermal printing head manufacturing method

Abstract

A method of manufacturing a thermal printing head includes forming a layer of polyimide resin precursor on a heat-resistant resin substrate on which two parallel common electrodes and a large number of lead electrodes are formed beforehand in such a manner that the lead electrodes are separated from the common electrodes by a predetermined distance and are disposed on one side of the common electrodes in a vertical direction. It further includes performing a first etching on the layer of polyimide resin precursor such that a predetermined pattern is formed. Heat treatment is then performed on the layer of polyimide resin precursor to simultaneously form, between the lead electrodes and the common electrode disposed close to the lead electrodes, a polyimide resin heat accumulating layer as a base for a heating resistor as well as a polyimide resin insulating layer capable of electrically insulating a jumper wire connecting the common electrode disposed remote from the lead electrodes to the heating resistor on the common electrode disposed close to the lead electrodes. The heating resistor is then formed on the polyimide resin heat accumulating layer. Finally, a wire connecting the heating resistor to the two common electrodes and to the plurality of lead electrodes is formed.