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. 07, 1980
Filed:
Aug. 07, 1979
Applicant:
Inventors:
Assignee:
Toray Industries, Inc., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B29C / ; B29C / ;
U.S. Cl.
CPC ...
2642358 ;
Abstract
The present invention relates to a process for preparing a polyester film which has not only uniaxially enhanced mechanical properties but also biaxially enhanced mechanical properties. The process involves heat-setting a biaxially oriented polyester film at a temperature above that used for the machine and transverse direction stretching and above that used for the machine direction re-stretching, but at least 10.degree. C. below the melting point of the polyester, then re-stretching the film in both the machine and transverse directions, and re-heat-setting the film.