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:
Nov. 11, 1986
Filed:
Jun. 11, 1985
Applicant:
Inventor:
Michael Hirschberger, Sylvania, OH (US);
Assignee:
Owens-Illinois, Inc., Toledo, OH (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B29C / ; B29C / ;
U.S. Cl.
CPC ...
264514 ; 264515 ; 264173 ; 4251311 ; 4251331 ;
Abstract
A process is disclosed for extruding heavy tubular shaped articles from high molecular weight, high density linear ethylene polymers under shearstress conditions such that the exterior surface of the extruded article would undergo melt fracture. Melt fracture is avoided by coextruding a thin layer of a second ethylene polymer in contact with the high molecular weight, high density linear ethylene polymer and the outer lip of the annular die. The second ethylene polymer has melt flow properties such that it does not exhibit melt fracture at the temperature and shear rate employed in extruding the tubular shaped article.