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:
Aug. 06, 1991
Filed:
Jul. 06, 1990
Masumi Saruwatari, Nagoya, JP;
Yasuhiko Ohta, Nagoya, JP;
Yasuhiro Fujii, Nagoya, JP;
Yasuko Honji, Ichinomiya, JP;
Shoichi Tsuji, Tanashi, JP;
Shinobu Moriya, Nagoya, JP;
Mitsui Toatsu Chemicals, Inc., Tokyo, JP;
Abstract
In the preparation of a film by melt-extrusion process of thermoplastic polyimide, static charge is applied to a molten film, primary cooling is carried out by adhering the film to a cooling roller having a surface temperature in the range of from the glass transition temperature of said polyimide -50.degree. C. to the glass transition temperature -15.degree. C., the film is successively cooled to 60.degree. C. and less without bringing the film into contact with rollers, and is taken up under tension to give a polyimide film.