Patent ID: 6045737
Filing Date: 2000-04-04
Classification: B29C,B29K,C09K

Abstract:
A method of preparing a multilayer multiaxially oriented film from a liquid crystalline polymer (LCP) and a thermoplastic polymer (TP) comprising the steps of:(a) continuously coextruding a liquid crystal polymer layer and a thermoplastic polymer layer;(b) said LCP layer having a multiaxial orientation formed by subjecting axially flowing LCP material to transverse-directional motions, thereby straining the axial flow; and(c) solidifying the orientation formed in step (b) wherein said layers are respective portions of an integral film structure formed by a single die-forming process and wherein said integral film structure is formed by employing a tubular die having three concentric rotors which form two annular flow channels therebetween; supplying the respective polymers through said channels; rotating at least the outer rotor which is contacting said LCP in a first direction while rotating the middle rotor in the opposite direction; and joining the respective polymer films formed in said channels to form said integral film structure.