Tandem type printing system

摘要

A first printing device forms position alignment marks on a front surface of a web in addition to front-surface images. Information on interval of the printed alignment marks is transmitted to a second printing device, which is for forming rear-surface images on a rear surface of the web. The second printing device detects the position alignment marks. A controller controls a transport speed of the web in the second printing device such that the rear-surface images will be formed in position alignment with the front-surface images based on ideal detection timing and actual detection timing of the position alignment marks.