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:
Jul. 27, 1999
Filed:
Oct. 17, 1997
Hideo Nomura, Chiba, JP;
Mituo Maeda, Ibaraki, JP;
Sumitomo Chemical Co., Ltd., Osaka, JP;
Abstract
A melt extrusion processing method of a thermoplastic resin, wherein a thermoplastic resin having a flow temperature of 200.degree. C. or higher is subjected to extrusion processing using a melt kneading type extruder in which a vent port is provided at a downstream position by length L from the most upper stream portion of a melt kneading type extruder screw and L/D is from 4 to 18 (wherein D indicates the screw diameter and D and L are in the same scale unit), while continuously sucking from the said vent port at a reduced pressure of lower then 660 mmHg. The invention provides a method which causes little resin degradation in an extruder to give an extruded article containing small amounts of discolored and degraded materials even when the processing is conducted for a relatively long time.