Influence of solution properties in the laser forward transfer of liquids

• Published in: Applied surface science Vol. 258; no. 23; pp. 9379 - 9384
• Main Authors: Dinca, V., Patrascioiu, A., Fernández-Pradas, J.M., Morenza, J.L., Serra, P.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 15.09.2012; Elsevier
• Subjects: Biomolecule printing; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron and ion emission by liquids and solids; impact phenomena; Exact sciences and technology; Impact phenomena (including electron spectra and sputtering); Laser forward transfer; Laser-beam impact phenomena; Physics; Time-resolved imaging; Laser forward transfer; Biomolecule printing; Time-resolved imaging; Water; Viscosity; Liquid state; Time resolution; Imaging; Glycerol; Laser beams
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2012.02.007

► Influence of viscosity on the LIFT dynamics in the case of a Newtonian liquid. ► A very broad range of viscosities (1.9–850mPas) can be LIFT printed. ► Printing uniformity correlates well with the stability of the ejection process. The influence of the viscosity of the printed solution on the laser-induced forward transfer (LIFT) of liquids is investigated. A set of water and glycerol mixtures with different glycerol content are prepared with the aim of having a collection of solutions covering a wide range of viscosities, from 1.9 to 850mPas. Arrays of micrometric droplets of those solutions are spotted through LIFT and characterized by means of optical microscopy, revealing that for all the analyzed solutions there always exists a range of laser fluences leading to the formation of regular circular droplets, with that range increasing and widening with viscosity. The dynamics of liquid ejection is investigated through time-resolved imaging with the aim of understanding the role of viscosity in the process, and its influence on the morphology of the deposited droplets. The acquired stop-action movies reveal that liquid transfer proceeds mainly through jetting, with the exception of LIFT at low viscosities and high laser fluences, in which bursting develops. From this study it is concluded that viscosity plays an important role in the stabilization of liquid ejection and transport, which contributes to the uniformity of the deposited droplets.