オフセット輪転機に生じる印刷縞の発生メカニズム

概要

論文の詳細を見る
A print defect of streaking takes place in an offset printing machine after a ditch of a blanket drum collides with the ditch of another facing blanket drum and a proof cylinder. The streaking is visible just after the collision on a paper printed half-tone solid image. These experimental features suggest that the defect is caused by the vibration of blanket drums in the opposite direction due to the collision of these ditches, that is, caused by the alternation of the print pressure due to the relative displacement of a facing blanket drums. This hypothesis was proven by the experiment that the pitch and phase of streaking coincided with those of the relative displacement that determined the print pressure. The experimental results were confirmed by the numerical calculation based on a simple linear vibration model of eight-degree-of-freedom. In conclusion, the mechanism and characteristics of the vibration were clarified and the present investigation has been utilized for the improvement of the design.
2009-07-25