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:
Mar. 04, 2003
Filed:
Jun. 25, 2001
Yuji Terado, Fukuoka, JP;
Hiroshi Suizu, Tokyo, JP;
Masatoshi Takagi, Chiba, JP;
Masanobu Ajioka, Fukuoka, JP;
Shoji Hiraoka, Yamaguchi, JP;
Masayuki Sakai, Yamaguchi, JP;
Hiroyuki Suzuki, Fukuoka, JP;
Ryo Shinagawa, Fukuoka, JP;
Shinji Ogawa, Fukuoka, JP;
Yasushi Kotaki, Fukuoka, JP;
Mitsui Chemicals, Inc., Tokyo, JP;
Abstract
The invention relates to a process for producing an aliphatic polyester excellent in stability which includes subjecting an aliphatic polyester containing at least 50% of an aliphatic hydroxycarboxylic acid unit, obtainable by solid-phase polymerization under a flowing gas in the presence of a volatile catalyst so as to have a desired weight average molecular weight within the range of 50,000 to 1,000,000, to a heat treatment at a temperature equal to or higher than the reaction temperature of the solid-phase polymerization under a flowing gas with maintaining the aliphatic polyester in a solid state. According to the process of the invention, an aliphatic polyester excellent in stability at molding and storage stability is obtained.