Patent ID: 6513894
Filing Date: 2003-02-04
Classification: B01J,B01L,B41J

Abstract:
A method for expelling a drop of a fluid from an orifice, comprising:providing a body defining a passageway terminating at an orifice, fluid being contained in the passageway proximate to the orifice, said fluid forming a meniscus in the passageway; a first withdrawing of the fluid in the passageway in a first direction from the orifice; after said first withdrawing, propelling the fluid in the passageway in a second direction opposite to the first direction and toward the orifice; after said propelling, performing a second withdrawing of the fluid in the passageway in the first direction; continuing said second withdrawing for a duration of time sufficient to begin retracting the portion of the meniscus in contact with the orifice; ending said second withdrawing; and after beginning said retracting, expelling a drop of the fluid from the orifice; wherein said first withdrawing is for a first duration of time, and said propelling is for a second duration of time less than the first duration of time.