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. 13, 2020
Filed:
Feb. 05, 2018
Kureha Corporation, Chuo-ku, Tokyo, JP;
Michihisa Miyahara, Tokyo, JP;
Kenji Suzuki, Tokyo, JP;
Hiroshi Sakabe, Tokyo, JP;
Yoshikatsu Satake, Tokyo, JP;
KUREHA CORPORATION, Tokyo, JP;
Abstract
The production method of the present invention includes a step of supplying an organic polar solvent, a sulfur source, and a dihalo aromatic compound as reaction raw materials to at least one of a plurality of reaction vessels mutually communicated via a gas phase; a step of removing at least a portion of the water present in the reaction vessels; and a step of performing a polymerization reaction. These steps are carried out in parallel, and the reaction mixture is sequentially moved between reaction vessels. At that time, the internal temperatures of the reaction vessels are all not less than 150° C.