Patent ID: 7077334

Claim:
A method for printing drops of liquid, the method comprising the steps of: a. providing a quantity of liquid to be printed; b. providing a nozzle, the nozzle defining an orifice that is aligned along an axis, and having an annular land surrounding the orifice, the land being bounded perimetrically by an outer edge; c. coupling the quantity of liquid hydraulically to the orifice; d. filling the orifice with some of the quantity of liquid; e. establishing within the liquid in the orifice, a steady state pressure that is greater than atmospheric by an overpressure, great enough to cause a cap of liquid to cover the annular land and the orifice; f. selectively causing a single drop of liquid to detach from the cap of liquid and to be ejected from the orifice; and g. allowing pressure at the orifice to return to the steady state pressure, such that a cap of liquid covers the annular land and the orifice.