| 摘要 |
PURPOSE:To prevent possible uneven printing density by making the resistance value distribution of heating resistors lower gradually away from the power source of the common electrode. CONSTITUTION:In a plurality of heating resistors divided into blocks each 224 pieces, the resistance value distribution of the heating resistors 51-5n is made lower gradually away from terminals 2a and 2b, that is, toward the center thereof as shown by the solid line (d). An electrode conductor 2 is formed by thick film technology or thin film technology. On the other hand, the heating resistors 5 is also formed by employing the widely accepted conventional thick film technology or thin film technology. In the case of a thick film type thermal head, printing conditions of a resisting paste are changed to make the width of the heating resistors 51-5n larger toward the center. In the case of a thin film type thermal head, a so-called one-point radiation is done with an evaporation source brought closer to an insulating substrate in the sputtering to make the amount of evaporation larger toward the center. |
