I have examined factors for implementing a high-speed, low-power-consumption thermal head. In conventional thermal heads, a heat insulation layer is provided between the heating resistor and the radiator. I found it desirable to implement fast operation and low power consumption to lower the thermal conductivity of the heat insulation layer and to thin the heat insulation layer. I also found there is an optimum heat characteristic to the thickness of one heat insulation layer. I assumed polyimide as a material for the heat insulation layer which could materialize the hypothesis, and studied necessary items based on the thermal calculation. I manufactured a trial thermal head on the basis of this result and confirmed that our assumptions were correct. In addition, to confirm that the assumption is also ultimately correct, I fabricated a trial thermal head only consisting of a heating resistor and without a protective coat and a heat insulation layer. I confirmed that the structure with only the heating resistor exhibited excellent heat response and consumed less power necessary for heating.