| 摘要 |
PURPOSE:To prevent the generation of irregularity of printing density, by connecting a trimming resistor to a heat generating resistor in series and trimming the trimming resistor to adjust the power applied to the heat generating resistor. CONSTITUTION:A heat resistance layer 3 is formed to the upper surface of the glaze layer 2 on a substrate 1 and a large number of heat generating resistors 4 are formed to the upper surface of the heat resistance layer 3 and trimming resistors 5 are formed on the same straight line as the heat generating resistors 4. The resistors 4, 5 are connected by lead wires 6, 7, 8. Each of the heat generating resistors 4 is set to R2 and each of the trimming resistors 5 is set to R1. The power P2 applied t the heat generating resistor 4 becomes V2<2>/R2. P2 is a value required from printing density and R2 is a value calculated by actual measurement and a value to be adjusted is V2. When the voltage V0 applied to the whole is made constant, the resistance value R1 of the trimming resistor 5 connected to the heat generating resistor 4 is determined. By trimming the resistor 5 so as to reach the value calculated by operation, V1 is determined and the voltage V2 applied to the heat generating resistor 4 is determined and the power P2 is determined. |
