Thermal head method of manufacturing the same

Abstract

The improved thermal head of the invention is the one having a protective film of a heater formed on the heater, the protective film comprising a ceramic-based lower protective layer composed of at least one sub-layer and a carbon-based upper protective layer formed on the lower protective layer, wherein a surface of the lower protective layer on which the upper protective layer is to be formed has a surface roughness value Ra of 0.005 to 0.5 .mu.m; or the one in which the depth of a depression step which may be formed on the surface of the lower protective layer due to the thickness of the electrodes used for supplying power to the heater (or heat-generating resistor) was reduced to 0.2 .mu.m or less. Therefore, the thermal head of the invention has a protective film which has significantly reduced corrosion and wear, which is advantageously protected from cracks and peeling-off due to heat and mechanical impact and which allows the thermal head to have a sufficient durability to exhibit high reliability over an extended period of time, thereby ensuring that the thermal recording of high-quality images is consistently performed over an extended period of operation.

Dependencies are inferred from the claim text.