Machine direction orientation of nylon film.

摘要

A process for machine direction orientation of a nylon film (28) using counter-rotating rolls (20,23) in which nip rolls (22,24) are applied to both the slow orientation roll (22) and the fast orientation roll (24) with a substantially uniform force in the range of 15 to 45 N/cm width of nip roll. The temperature of the slow roll (22) is held between 70 and 180°C and the temperature of the fast roll (24) is held between the temperature of the first roll and 20°C below the melting temperature of the nylon film (28). The distance between the orientation rolls (22,24) is in the range of 10 to 2050 µm.

Apparatus for carrying out the process includes a chill roll (16) and heat roll (18) between the extruder (14) and the orientation rolls (22,24) and a quench roll (26) between the orientation rolls and a wind-up mandrel (27).