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:
Apr. 08, 2014
Filed:
Feb. 17, 2010
Yoshinori Suzuki, Tokyo, JP;
Fumio Maeda, Tokyo, JP;
Takahiro Watanabe, Tokyo, JP;
Hiroyuki Sato, Tokyo, JP;
Yoshinori Suzuki, Tokyo, JP;
Fumio Maeda, Tokyo, JP;
Takahiro Watanabe, Tokyo, JP;
Hiroyuki Sato, Tokyo, JP;
Kureha Corporation, Tokyo, JP;
Abstract
A process for producing an aliphatic polyester, comprising: subjecting at least two serial stages of bulk-phase ring-opening polymerization and a solid-phase polymerization step, wherein a cyclic ester held in a dry air atmosphere is supplied to a first reactor to perform a first stage polymerization, thereby obtaining a partially polymerized molten product, and the resultant partially polymerized molten product is supplied to a second reactor held under a dry inert gas atmosphere to perform a second stage polymerization. As a result, the production efficiency can be improved, while maintaining excellent properties of the aliphatic polyester product.