Shrink film

US7504141B2 · kind B2 · utility

Assignee

• Borealis Technology Oy · FI

Inventors

• Ole Jan Myhre · Stathelle, NO
• Merete Skar · Stathelle, NO
• Hans Georg Daviknes · Stathelle, NO
• Kjetil Larsen Brove · Stathelle, NO
• Geir Morten Johansen · Stathelle, NO

Key dates

• Filing date: Jul 29, 2003
• Grant date: Mar 17, 2009
• Expiry date: Sep 28, 2024

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/1359
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A shrink film comprising a polyethylene film, characterized in that said polyethylene is an ethylene copolymer mixture having a molecular weight distribution in the range 10 to 35, a density of 915 to 940 kg/m3, a weight average molecular weight of at least 100000 D and an MFR2.16 (190° C.) of 0.1 to 0.9 kg/m3, which copolymer mixture is produced by a two or more stage copolymerization of ethylene and 2 to 10% mole (relative to ethylene) of a C3-12 alpha-olefin comonomer in a series of reactors including at least one slurry loop reactor and at least one gas phase reactor using a heterogeneous Ziegler-Natta catalyst.