Abstract: A drop-on-demand printer having a row of ink ejection locations (2) for ejecting plural ink droplets, each ejection location (2) having an associated ejection electrode (40) to which a voltage is applied for causing electrostatic ejection of the droplets from the respective ejection location (2); a guard channel (5) disposed between adjacent ejection locations (2), each guard channel (5) having an electrode (50) disposed therein; and control means for applying a voltage to said guard channel electrodes (50), said applied voltage being the average of the voltages applied in operation over a given time to the adjacent ejection location electrodes.

Abstract: A drop-on-demand printer having a row of ink ejection locations (2) for ejecting plural ink droplets, each ejection location (2) having an associated ejection electrode (40) to which a voltage is applied for causing electrostatic ejection of the droplets from the respective ejection location (2); a guard channel (5) disposed between adjacent ejection locations (2), each guard channel (5) having an electrode (50) disposed therein; and control means for applying a voltage to said guard channel electrodes (50), said applied voltage being the average of the voltages applied in operati n over a given time to the adjacent ejection location electrodes.

Abstract: The present invention relates to liquid projection apparatus in the form of a face-shooter array. Material layers are used as the basis to fabricate the device to overcome constructional difficulties associated with other technologies. The device utilizes excitation of the surface layers (100) incorporating nozzles (8) which are arranged over one surface layer with addressability, forming a liquid projection array, capable of operation at high frequencies with a wide range of liquids.