Characterization of inkjet inks and the skin layer by ultrasonic viscoelastic measurements

Abstract The ultrasonic viscoelasticity measurement method can evaluate bulk properties and surface properties of samples at megahertz frequencies. As an application example, it was shown that it is possible to distinguish between samples of different manufacturers and compositions in commercially available inkjet inks with small viscosity terms, which was said to be difficult to do with previous methods. Since the high-frequency viscoelasticity measurement method has a structure that matches well with the ejection principle of the inkjet method in terms of stress wave propagation, the results obtained are thought to provide useful parameters for inkjet ejection analysis. Furthermore, we will introduce a method for obtaining equivalent viscoelasticity measurement results to those for a single material and a laminated material by using a measurement model that mimics the skin layer on the polymer surface, which is a problem when hardening gels and other materials, while also grasping the skin layer thickness and density.