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:
May. 13, 2003
Filed:
Jun. 11, 2001
Kazuki Hatono, Iwakuni, JP;
Masumi Hirata, Iwakuni, JP;
Hiroaki Kaneko, Iwakuni, JP;
Toru Sawaki, Iwakuni, JP;
Wataru Funakoshi, Iwakuni, JP;
Katsushi Sasaki, Iwakuni, JP;
Masasi Simonaru, Iwakuni, JP;
Kouji Kiyoshige, Iwakuni, JP;
Teijin Limited, Osaka, JP;
Abstract
A method of producing a polycarbonate or the like which is excellent in hydrolysis and heat stability such as a reduction in molecular weight at the time of molding and color retention and moldability such as releasability and transferability, rarely experiences residence deterioration such as coloring, crosslinking and gel formation and has an extremely small content of foreign matter by employing a special structure for an opening in the side surface of a horizontal cylindrical vacuum resin treating apparatus, supplying a molten polycarbonate into a unidirectional rotary intermeshing double-screw extruder under specific conditions, adding a specific agent under specific conditions and cleaning the inner surface of a production apparatus by a specific method.