The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 14, 2003
Filed:
Oct. 01, 2001
Merete Skar, Stathelle, NO;
Ole Jan Myhre, Pregarten, AT;
Arja Lehtinen, Helsinki, FI;
Harri Hokkanen, Helsinki, FI;
Hilkka Knuuttila, Porvoo, FI;
Kalle Kallio, Porvoo, FI;
Esa Kinnunen, Porvoo, FI;
Eija Lappi, Porvoo, FI;
Borealis Technology Oy, Porvoo, FI;
Abstract
This invention concerns process for producing polyethylene compositions, films prepared thereof and process for the preparation of the films. The process comprises subjecting ethylene, optionally hydrogen and comonomers to polymerization or copolymerization reactions in a multistage polymerization. At least one polymerization stage is conducted essentially in the absence of hydrogen. The polymerization reactions are carried out in the presence of a single-site catalyst capable of forming a composition comprising a low molecular weight component with MFR of at least 10 g/10 min and a density higher than the density of the composition and a high molecular weight component. The melt flow rate of the composition is in the range MFR =0.1-5.0 g/10 min and the density of the composition is 915-960 kg/m . The invention makes it possible to produce polyethylene compositions for manufacturing films with a good balance between optical and mechanical properties.