Überführungsband

摘要

A transfer belt (60) for carrying a paper sheet (40) in a papermachine from a press nip in a closed draw to a transfer point, where it is readily released. The belt comprises a supporting base (62) with a particle-filled polymer coating (80) on its paper-facing surface (66), which surface has a pressure-responsive recoverable degree of roughness. During compression in the nip, the surface (66) becomes relatively smooth to allow a thin, almost continuous water film (100) to form between the belt (60) and the sheet (40), which film holds the sheet to the transfer belt as it leaves the nip. Shortly after leaving the nip, the belt surface recovers its uncompressed roughness, breaking up the water film so as to facilitate the release of the sheet from the belt as it reaches the transfer point.