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. 22, 2013
Filed:
Feb. 16, 2010
Joseph Dooley, Midland, MI (US);
Jeffrey M. Robacki, Freeland, MI (US);
Mark A. Barger, Midland, MI (US);
Robert E. Wrisley, Clare, MI (US);
Sam L. Crabtree, Midland, MI (US);
Calvin L. Pavlicek, Midland, MI (US);
Joseph Dooley, Midland, MI (US);
Jeffrey M. Robacki, Freeland, MI (US);
Mark A. Barger, Midland, MI (US);
Robert E. Wrisley, Clare, MI (US);
Sam L. Crabtree, Midland, MI (US);
Calvin L. Pavlicek, Midland, MI (US);
Dow Global Technologies Inc., Midland, MI (US);
Abstract
Disclosed are multilayer film structures having annular profiles, and methods and apparatus of making the structures disclosed. The annular multilayer articles have a uniform thickness, at least four layers and comprise overlapped and non-overlapped circumferential areas; wherein the layer structure of the non-overlapped area is doubled in the overlapped layer. A method of making the structure includes providing a multilayer flow stream with at least four layers of thermoplastic resinous materials; feeding the multilayer flow stream to a distribution manifold of an annular die to form an annular multilayer flow stream; and removing the annular multilayer flow stream from the annular die to form the annular multilayer structure. Also disclosed is an apparatus, comprising: a feedblock, with optional layer multiplier, that provides a multilayer flow stream of at least four layers to the manifold of an annular die; and an annular die having at least one distribution manifold that extrudes a multilayer flow stream.