Extrusion roller apparatus and nip assembly including the apparatus

Abstract

A roller and extrusion nip assembly are disclosed for extrusion coating and lamination. The roller includes a steel core, an intermediate rubber layer, and an outer sleeve of fluorinated ethylene polymer (FEP) or perfluoroalkoxy alkane (PFA). The outer sleeve extends in a single piece along at least half of the roller length and is polished to achieve controlled surface roughness. The rubber layer provides compliance for web handling, while the fluoropolymer sleeve prevents sticking of extruded polymer melt. The roller exhibits hardness between 55 and 95 Shore A, with the intermediate layer hardness between 40 and 70 Shore A. Integrated into a nip assembly with a chill roll, backing roll, and die, the roller eliminates the need for Teflon tape bands, reduces downtime from roll wraps, and supports high-speed operation while maintaining product quality.

Dependencies are inferred from the claim text.