Patent ID: 6827886
Filing Date: 2004-12-07
Classification: B29C,Y10T

Abstract:
A method for making a multilayered optical film, comprising:(a) providing at least a first and a second stream of resin; (b) providing a feeder tube plate having a first plurality of conduits, and having a second plurality of conduits interleaved with the first plurality of conduits; (c) feeding the first stream into the first plurality of conduits and the second stream into the second plurality of conduits; (d) providing a slot die for each of the first and second plurality of conduits such that the first and second streams are divided into a plurality of interleaved layers to yield a composite stream; (e) passing the composite stream through an extrusion die to form a multilayer web in which each layer is generally parallel to the major surface of adjacent layers; and (f) heating the first and second streams of resin with at least one axial rod heater that extends along at least one of the first and second plurality of conduits.