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. 28, 2006
Filed:
Aug. 06, 2001
Kohei Yamamoto, Kawagoe, JP;
Tsutomu Tani, Kawagoe, JP;
Takashi Aoki, Kawagoe, JP;
Yoshio Hata, Hokkaido, JP;
Kohei Yamamoto, Kawagoe, JP;
Tsutomu Tani, Kawagoe, JP;
Takashi Aoki, Kawagoe, JP;
Yoshio Hata, Hokkaido, JP;
Wako Pure Chemical Industries, Ltd., Osaka, JP;
Takeda Pharmaceutical Company Limited, Osaka, JP;
Abstract
A process for producing a lactic acid polymer of 15,000 to 50,000 in weight-average molecular weight, the content of polymeric materials having not more than about 5,000 in weight-average molecular weight therein being not more than about 5% by weight, characterized by hydrolyzing a high molecular weight lactic acid polymer, placing the resultant solution comprising the hydrolyzed product under a condition capable of precipitating the objective lactic acid polymer, separating the precipitated lactic acid polymer and collecting them. The lactic acid polymer is useful as a matrix for sustained-release preparations. The sustained-release microcapsule preparation encapsulating a physiologically active substance can fully prevent the initial excessive release of the physiologically active substance from the microcapsules and keep a stable release rate over a long period of time.