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. 01, 2005
Filed:
Sep. 20, 2000
Mikio Watanabe, Kanagawa, JP;
Jiro Takano, Kanagawa, JP;
Yoshimi Ishihara, Kanagawa, JP;
Masahiro Murakami, Osaka, JP;
Mikio Watanabe, Kanagawa, JP;
Jiro Takano, Kanagawa, JP;
Yoshimi Ishihara, Kanagawa, JP;
Masahiro Murakami, Osaka, JP;
Amato Pharmaceutical Products, Ltd., Kyoto, JP;
Abstract
The object of the present invention is to provide a novel method for effectively producing a cyclic lactic acid oligomer, and a cyclic lactic acid oligomer produced by the method. According to the present invention, there is provided a method for producing a cyclic lactic acid oligomer represented by the following formula ():wherein m represents an integer of 1 to 30,wherein lactides are polymerized in the presence of an alkali metal compound represented by the following formula ():R—Y—Me  ()wherein R represents an aliphatic group, aromatic group, —Si(R)(R)(R), —CH(R) CONRRor —CH(R)COOR, wherein each of R, Rand Rindependently represents an aliphatic or aromatic group, Rrepresents an aliphatic group, each of Rand Rindependently represents a hydrogen atom, aliphatic group or aromatic group,