UV–Visible Spectroscopy for Quantification of Drop-on-Demand Inkjet Performance

Abstract

Drop-on-demand inkjet technology offers a method through which nano- to microgram quantities of a substance can be delivered to a precise target location. However, few measurement techniques exist to quantify the material dispensed in quantities representative of those deposited on a typical target. While many methods exist that are suited to quantitate the cumulative material dispensed by large numbers of drops, few are capable of adequately quantifying subthousand drop counts. This gap in the quantitation methodology is significant since typically the first few drops in a burst have different mass from that of the subsequent drops. A UV–visible spectroscopic method is presented here as a means to quantify the dispensed material associated with drops numbering in the few tens to hundreds, with this method exhibiting excellent repeatability and reproducibility without the need for lengthy calibrations or sample preparation times. The resolution and precision of this method make it an attractive choice for...