Patent ID: 7771023

Claim:
A method of ejecting drops of an ejectable liquid from a printhead, the printhead comprising a plurality of nozzles; a bubble forming chamber corresponding to each of the nozzles respectively, the bubble forming chambers adapted to contain a bubble forming liquid; and, at least one heater associated with each of the bubble forming chambers respectively, the heater having electrodes for connection to a power supply and heater elements configured for thermal contact with the bubble forming liquid; wherein, the heater element is supported within the bubble forming chamber by the electrodes such that it does not contact the bubble forming chamber, the method comprising the steps of: placing the bubble forming liquid into thermal contact with the heater elements; and, providing each of the heater elements with electrical pulses, each electrical pulse having sufficient energy to heat one of the heater elements to a temperature above the boiling point of the bubble forming liquid to form a gas bubble such that a drop of an ejectable liquid is ejected through the corresponding nozzle; wherein, each of the electrical pulses has a duration less than 2 micro-seconds and less than 100 nano-Joules.