Fluid ejector

A method of ejecting discrete volumes of ejectant, the method comprising:

• ejecting the ejectant onto a substrate or a web using the fluid ejector comprising:
• a rigid body having opposing first and second surfaces and at least one nozzle defined between the first and second surfaces, each of the at least one nozzle defined by a conduit extending through the rigid body to connect a first orifice defined at the first surface of the rigid body and a second orifice defined at the second surface of the rigid body;
• an ejectant supply device for supplying ejectant to each of one or more of the at least one nozzle through the second orifice of the nozzle;
• and
• a gas supply device for supplying a gas to the one or more nozzles through the one or more first orifices, the gas supply device defining a gas outlet, the gas supply device and the rigid body movable relative to each other,
• wherein:
• the ejectant supply device is operable to supply the ejectant to each of the one or more nozzles, through the second orifice of the nozzle, at a pressure above ambient pressure, and
• relative movement of the gas supply device and the rigid body exposes the one or more first orifices of the one or more nozzles to the gas outlet, enabling the gas supply device to supply gas to the one or more first orifices of the one or more nozzles at a pressure above ambient pressure, wherein for each of the one or more nozzles a pressure difference created thereby between the first orifice and the second orifice of the nozzle causes ejection of the ejectant from the nozzle through the second orifice.