How can I avoid flow lines in calendar films generated by calendaring process?
The parameters having a positive influence on the apparition of flow lines are: – Use our special grade SolVin 460SL. – Reduce the temperature differences between film on the roll and rolling bank. – Increase the size of rolling bank. – Increase the level of processing aids (need very well balanced, too much shows a reverse effect). – Increase temperature differences between the two last rolls. – Increase rotating calendar nip (very important rotating regular). – Reduce calendar speed. – If possible, increase the thickness of the film. – Reduce the friction on the take off system. – Take a very balanced recipe (lubricants, processing aids and MBS/Acrylic Modifier) for the best melt flow. f.