| 摘要 |
PURPOSE:To obtain high printing quality, by a method wherein a protective layer is formed so that the thickness is increased on wiring and reduced on a heat generating resistor and a recessed step part is provided to the part of the heat generating resistor by said protective layer and a printing dot is made circular or square. CONSTITUTION:A protective layer 1 is formed so as to be made thick on wiring 2 and thin on a heat generating resistor 3 and, by largely providing a recessed step part on the heat generating resistor 3, recording paper 7 is contacted with the central part (the bottom) of the recessed part) of the heat generating resistor 3 to maximally receive heat from the heat generating resistor 3 and heat receiving quantity is reduced as the recording paper 7 goes away from said resistor 3. By this method, a color is formed at the central part of the heat generating resistor 3. Further, the projection 8 provided to the bottom of the circular step part is made lower than the depth of a gate shaped step part and the width thereof is made almost the same to that of the wiring 2 or the arrangement pitch of the wiring 2. By this method, the recording paper 7 sent by a platen roller 6 is certainly contacted with the projection 8 and the heat from the heat generating resistor 3 is certainly conducted to the recording paper 7 from the central part thereof to obtain a square or circular printing dot. |
