Patent ID: 6200424
Filing Date: 2001-03-13
Classification: D21G

Abstract:
In an arrangement for calendering a board web including a calender comprising first and second calender rolls arranged to form a calendering nip through which the board web passes, at least said first calender roll being heated to a temperature such that a surface layer on a first side of the board web contacting said first calender roll reaches its vitrification temperature in the calendering nip, the improvement comprising:a film press arranged directly before the calendering nip in a running direction of the board web, said film press comprisinga film press nip through which the board web passes, andfirst moistening means for transferring a liquid onto said first side of the board web in said film press nip to form a liquid layer on said first side of the board web, andwherein the board web is transferred from said film press nip into the calendering nip such that the surface layer of the web on said first side of the board web is at the moisture level determined by said film press to produce a controlled moisture gradient.