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. 23, 2001
Filed:
May. 13, 1999
Rajen M. Patel, Lake Jackson, TX (US);
Jacquelyn A. deGroot, Lake Jackson, TX (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
This invention relates to an improved shrink film obtained by selectively controlling and optimizing the melt index and density differential between at least two polyolefin polymer components to provide narrow density splits. One aspect of this invention relates to a biaxially oriented polyolefin shrink film having balanced properties and another aspect of this invention relates to an oriented shrink film having improved toughness. This invention also relates to a biaxial orientation method of making an improved shrink film using elaborate shrink orientation techniques such as tenter framing, double-bubble, trapped bubble, tape orientation or combination thereof. Most preferably, the first polyolefin polymer component is a lower density, substantially linear ethylene/&agr;-olefin interpolymer and the second polyolefin polymer component is a higher density, heterogeneously branched ethylene/&agr;-olefin interpolymer.