Study on Paper Releasing Phenomena in Offset Printing by Acoustic Approach

It is generally said that the periodical sound caused by paper feeding in offset printing relates to the paper release property of blanket. We focused on this release sound, and studied this release phenomenon by acoustic approach. A test chart for detecting the position of pattern image printed at the nip of between blanket cylinder and impression cylinder (B/I nip) was developed and combined with acoustic measurement. The release position of paper on blanket during printing of image area could be detected. It was found that the paper release sound was caused by paper release position at inked image edge on blanket.