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:
Jun. 09, 1981
Filed:
Jun. 18, 1979
Applicant:
Inventor:
Robert C Slocumb, New Brighton, MN (US);
Assignee:
Conwed Corporation, St. Paul, MN (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B29D / ;
U.S. Cl.
CPC ...
264 53 ; 2642107 ; 264D / ;
Abstract
A method for reducing the aging period of foams produced using a gaseous expansion agent is disclosed which includes biaxial orientation of the thermoplastic polymer foam. The foam is cooled after it is extruded and blown up from a tubular die, the cooling being to a temperature at least 40.degree. C. below its melting point. Thereafter, the foam is biaxially oriented to a dimension at least 25% greater in both radial and axial directions than the dimensions of the extruded, blown up, cooled foam.