Over the past several years, the introduction of ultrawide format printers capable of printing on untreated and uncoated substrates, such as vinyls, have penetrated into the digital printing arena. Most of the current printer systems use glycol acetates and glycol ether acetates, especially in the systems using piezo drop-on-demand technologies. The few continuous printer systems used in this market are using MEK-based solvent inks. Such solvents are not considered “environmentally friendly”. In many instances, there is a strong demand for these imagers to use aqueous-based ink systems. This paper investigates the surface properties of solvent and aqueous inks and four commercially available vinyl substrates, as well as the inherent ink-substrate interactions.The goal is to be able to predict how ink will spread on and adhere to a vinyl substrate. In theory, the vinyl and ink surface energies will determine the work of adhesion, Wa, between the two. Three approaches are used to determine Wa. The first two approaches involve directly monitoring the ink–vinyl interaction: the ‘Adhesion tape test’, which is currently in use for quality control of ink jet inks, and the application of Young's equation, which involves the measurement of the ink surface energy and the ink–vinyl contact angle. The third approach attempts to derive Wa from solely the surface energies of the ink and vinyl. Two methods are used to calculate the vinyl surface energies: the polar-dispersive two component method and the acid base three component method. Both methods are based on the contact angles formed by pure liquids on the vinyl. The ink surface energies are measured directly using the modified Wilhelmy plate (static) and maximum bubble pressure (dynamic) methods. The ink–vinyl interfacial energies are calculated from the individual surface energies and the ink–vinyl contact angle by means of Young's equation. Finally, we relate these results to the adhesion test of the inks on vinyl substrates.
Eric Durieux, Michael Fein, Nathaniel R. Schwartz, Jennifer Renner, Kelly Schoen, "An Analysis of Ink Jet Ink and Untreated Vinyl Interactions" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP16), 2000, pp 501 - 506, https://doi.org/10.2352/ISSN.2169-4451.2000.16.1.art00023_2