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:
Nov. 24, 2009
Filed:
Oct. 08, 2003
Applicants:
Hiroyuki Sato, Fukushima, JP;
Tomohiro Hoshi, Fukushima, JP;
Yasushi Okada, Fukushima, JP;
Yoshinori Suzuki, Fukushima, JP;
Inventors:
Hiroyuki Sato, Fukushima, JP;
Tomohiro Hoshi, Fukushima, JP;
Yasushi Okada, Fukushima, JP;
Yoshinori Suzuki, Fukushima, JP;
Assignee:
Kureha Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08G 63/06 (2006.01); C08G 63/08 (2006.01);
U.S. Cl.
CPC ...
Abstract
A process for producing an aliphatic polyester by subjecting a cyclic ester to ring-opening polymerization, which comprises adding water to a cyclic ester purified to the extent that a water content is at most 60 ppm to control an overall proton concentration in the cyclic ester, thereby controlling at least one physical property among melt viscosity, molecular weight and yellowness index of the resulting aliphatic polyester.