Patent · US Expired

Oriented coextruded films

US6423420B1 · kind B1 · utility

28Cited by
4References
31Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 20, 1999
Grant dateJul 23, 2002
Priority date
Expiry dateAug 20, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31913
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

An oriented multilayer film is provided, the film including in at least one outer layer an ethylene copolymer having a density of 0.900-0.935 g/cm3 and a CDBI of 50-95% the outer layer is in contact with a polypropylene core layer, and the film is made by coextrusion of the ethylene copolymer and the polypropylene layer and subsequent orientation. The coextruded layers can be uniaxially oriented or biaxially oriented without difficulties caused by presence of low molecular weight amorphous polymer fractions inherently present in traditional Ziegler-Natta linear low density polyethylene. The optical properties of oriented polypropylene films can be retained, while the sealing temperature is lowered and the heat seal strength and the hot tack performance properties are improved.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.