摘要 |
To relieve stresses within the rubber of a rubber blanket of a rotary offset printing machine, and prevent escape or squeeze-out of the rubber layer as the blanket rotates, the blanket is formed with interruptions or stress reliefs which, when the blanket is laid out flat, are located in zones corresponding to zones of the printed carrier which are free from printed subject matter, for example along fold lines of the carrier, surrounding pictures or non-printed subject matter, or the like. The interruptions or reliefs can be made by milling, for example longitudinal and transverse notches or grooves (2, 3) or by punching holes through the rubber layer (14), the holes being aligned in single or multiple rows along the zones free from printed subject matter. Stresses within the rubber layer, thus, can be relieved not only at the lateral edges, but also inwardly, and centrally, thereby improving overall register of printed subject matter.
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