First drop dissimilarity in drop-on-demand inkjet devices

• Published in: Physics of fluids (1994) Vol. 23; no. 1; pp. 012109 - 012109-6
• Main Authors: Famili, Amin, Palkar, Saurabh A., Baldy, William J.
• Format: Journal Article
• Language: English
• Published: Melville, NY American Institute of Physics 01.01.2011
• Subjects: AMPLITUDES; Applied sciences; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DEMAND; Electronics; Exact sciences and technology; FLOW VISUALIZATION; Hardware; IMAGE PROCESSING; Input-output equipment; MASS; OPERATION; SENSITIVITY; TRAJECTORIES; TWO-PHASE FLOW; VELOCITY; Ink jet printing; Measurement method; Volume measurement; Experimental study; Ultraviolet spectrometry; Drop
• ISSN: 1070-6631; 1089-7666
• DOI: 10.1063/1.3543758

As inkjet printing technology is increasingly applied in a broader array of applications, careful characterization of its method of use is critical due to its inherent sensitivity. A common operational mode in inkjet technology known as drop-on-demand ejection is used as a way to deliver a controlled quantity of material to a precise location on a target. This method of operation allows ejection of individual or a sequence (burst) of drops based on a timed trigger event. This work presents an examination of sequences of drops as they are ejected, indicating a number of phenomena that must be considered when designing a drop-on-demand inkjet system. These phenomena appear to be driven by differences between the first ejected drop in a burst and those that follow it and result in a break-down of the linear relationship expected between driving amplitude and drop mass. This first drop, as quantified by high-speed videography and subsequent image analysis, can be different in morphology, trajectory, velocity, and volume from subsequent drops within a burst. These findings were confirmed orthogonally by both volume and mass measurement techniques which allowed quantitation down to single drops.