To obtain a bubble jet (R) recording head in which excessive heat generation is controlled after bubbling of ink.
A channel 9 is formed by bonding a nozzle forming member 7 to a substrate 6. A heating resistor 13 and a stack 14 are provided in the channel 9. A first electrode 15 and a part of the upper metal electrode 2 of the stack 14 are arranged on the upper surface of the heating resistor 13, and a PCT thermistor 1 having a positive temperature coefficient of resistance is connected in series with the heating resistor 13. When a voltage is applied from a power supply 10 between lower metal electrodes 3, the heating resistor 13 is driven through the PCT thermistor 1 and the upper metal electrode 2 to generate heat. Consequently, ink in the channel 9 is heated and bubbled and an ink drop 12 is ejected from an ejection opening 5. When the temperature of the PCT thermistor 1 exceeds a threshold level subsequently, the resistance increases abruptly to bring about an insulated state and power supply to the heating resistor 13 is interrupted thus stopping heat generation.
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