Ink Flow Simulation of Offset Lithographic Printing: Comparison with Actual Print and Introduction of Additional Factors to the Model

Understanding ink flow behavior in offset lithographic printing machines is essential when optimizing process control, ink and water material design. We have developed an ink flow simulator to predict the ink film thickness anywhere on the rollers, plate or blanket of the machine and on printed paper at any time. Ink film thickness is sampled every 1 square millimeter of the surface, and calculated with a simple model that represents ink transfer from a rolling surface to another at a specified transfer rate in an actual roller configuration. The results of the simulation showed a strong correlation to the density measurement of corresponding actual print. Additional factors (degree of ink flow and its direction) were introduced to the model, resulting in a significant improvement in prediction accuracy.