In an ink ejection type recording device in which expansion of bubble ejects an ink droplet from a nozzle toward a recording medium, a heater formed in an ink channel is applied with a pulse of voltage by a driver circuit. The pulse of voltage is determined so that the surface of the heater in direct contact with the water-based ink is rapidly heated to a temperature causing to invoke caviar-wise nucleation of the ink that is in direct contact with the surface of the heater. Expanding bubbles resulting from the caviar-wise nucleation ejects an ink droplet from the nozzle, wherein the heater is heated at a heating speed in a range from 1.times.10.sup.8 .degree. C./sec to 5.times.10.sup.8 .degree.C./sec, and the surface of the heater is heated up from a room temperature to a temperature substantially equal to 320 C within a period of time ranging from 0.6 to 3 .mu.sec. By heating the heater under these conditions, the ink in contact with the heater starts boiling with a high boiling pressure, the generated bubble has a large volume, and thus the bubble can generate pressure sufficiently large to eject the ink droplet.