Viscoelastic Behavior of Printing Inks

Printing inks are best characterized as viscoelastic fluids. As more sophisticated and affordable instrumentation has become available, the ability to probe the elastic component has emerged. Several ink properties can be affected by these elastic features such as misting, ink dripping and flow behavior in a fountain, emulsified flow, recovery after shearing, and adhesion and release from waterless printing plates. The use of creep and oscillation methods provides a wide range of utility for assessing the elastic contribution to the printing phenomenon. Several case studies will be presented to exemplify the use of these measurements.