Effect of nip force on ink transfer in high resolution roll-to-roll printing

Abstract

In this paper, the effect of the nip force on the ink transfer in gravure printings was investigated. An adhesive force-based ink transfer model was suggested. This model is a function of the contact length between the ink and the substrate. The static simulation of the elastic deformation of the substrate was implemented under different nip forces. The simulation showed that the contact length (LIS) was increased as the nip force increased. Accordingly, the ink transfer ratio was increased as the nip force increased due to an increased contact length LIS. However, the fidelity of the printed pattern at high resolutions could deteriorate if the nip pressure was too high, especially when the doctoring ratio was greater than 1. Finally, experiments were conducted to verify the effect of the nip force, which showed good agreements with predicted results. The results of this study may be used as practical guidelines in determining the optimal range of the nip force in R2R gravure printing at high resolutions.