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:
May. 10, 1994
Filed:
Jun. 01, 1993
Eiichiro Takiyama, Kamakura, JP;
Takashi Fujimaki, Yokohama, JP;
Shigekatu Seki, Takasaki, JP;
Takao Hokari, Takasaki, JP;
Yoshitaka Hatano, Higashikanbara, JP;
Showa Highpolymer Co., Ltd., Tokyo, JP;
Abstract
A method for manufacturing a biodegradable high molecular weight aliphatic polyester. This method comprises the steps of: [A] synthesizing an aliphatic polyester having a number average molecular weight of at least 5,000 and/or a weight average molecular weight of at least 30,000 by reacting aliphatic or alicyclic glycol with aliphatic dicarboxylic acid or its anhydride, applying a 0.001-0.5 part by weight of organic or inorganic metallic compound as a catalyst with respect to 100 parts by weight of aliphatic polyester to be produced; [B] adding a 0.01-3 parts by weight of organic or inorganic phosphorus compound with respect to 100 parts by weight of aliphatic polyester upon completion of the reaction; and [C] reacting a 0.1-5 parts by weight of polyvalent isocyanate compound with 100 parts by weight of the aliphatic polyester so that the polyester has a number average molecular weight of at least 10,000 and/or a weight average molecular weight of at least 50,000.