The aim of this work is to measure the integrity of liquid toner images in both the development and transfer processes. To this end we have constructed a visualization cell in which we can observe the image deposition process due to a given applied voltage, and then measure the voltage required to break apart the image layer. Thus the cell permits the observation of both deposition and break-apart of toner images when either dc or low frequency ac fields are applied. The voltages required to compact the toner layer and to break it apart can be translated into consolidation stress and tensile strength of these materials; by this means we are able to compare inks in a quantitative manner.Using the visualization cell, we have examined the behavior of different liquid toners. We have observed the effects of different charge directors and their concentrations, as well as of different toner resins. While the cohesion varies according to the types of resins and of charge directors, there is no significant change in the behavior of the inks when charge-director concentrations are varied from a charge-director-to-toner weight ratio of 10mg/g to 50mg/g. We analyze the results with simple physical models that give a semiquantitative picture of the plastic behavior of inks at high particle fraction, up to the typical toner percentage of an image.
Shu Chang, Hank Till, Enrique Viturro, Keith Watson, Alberto T. Pérez, Antonio González, Antonio Castellanos, "Measurement of Toner Cohesion in Liquid Inks Using a Visualization Cell" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP14), 1998, pp 218 - 221, https://doi.org/10.2352/ISSN.2169-4451.1998.14.1.art00054_1