| 摘要 |
The invention relates to a process and a device for printing a material web by the offset printing process. After the contactless drying of the printed material web, the material web is guided in an S-shaped or Z-shaped path over a plurality of cooling rollers. At the same time, an easily splittable water film between the material web and the roller casing is formed by dampening the casing of the first cooling roller or the side of the material web which is cooled first. The result of this measure is that the still soft thermoplastic printing ink is not split upon physical contact of the material web with this and the other cooling rollers. The tendency of the material web to form corrugations transversely relative to the run-through direction is reduced because the splitting of the water film brings about a more uniform moisture distribution as a result of its different thickness in the printed and the non-printed and therefore more highly dried regions.
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