Nip Mechanics of Flexo Post-printing on Corrugated Board.

A finite element model of a flexo post-printing press for corrugated board has been developed to determine the principal causes for local variations of printing pressure. It is the first, full-structure model of the flexo post printing system, including liners and medium boards of corrugated board as well as printing plate and backing materials. A parametric study has been performed to investigate how the properties and dimensions of these materials used in the printing system affect the printing pressure variations. It showed that the liner board and the photopolymer properties had the greatest impact on the local variations of printing pressure. However, 'washboarding'. defined as a periodic geometric imperfection of the corrugated board structure, had a limited impact on the pressure variations. It has been demonstrated that alleviating the printing pressure variations is possible through the optimization of printing plate materials within a realistic range of constitutive parameters. [ABSTRACT FROM AUTHOR]