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. 05, 2005
Filed:
Apr. 19, 2001
Lüder Gerking, Berlin, DE;
Rainer Hagen, Berlin, DE;
Klaus Richter, Leipzig, DE;
Frank Idler, Potsdam, DE;
Winfried Reimann, Potsdam, DE;
Bernd Hanzsch, Geltow, DE;
Lüder Gerking, Berlin, DE;
Rainer Hagen, Berlin, DE;
Klaus Richter, Leipzig, DE;
Frank Idler, Potsdam, DE;
Winfried Reimann, Potsdam, DE;
Bernd Hanzsch, Geltow, DE;
Inventa-Fischer GmbH & Co. KG, Berlin, DE;
Abstract
The invention relates to a method for producing polylactic acid, comprising the steps of obtaining lactic acid from starchy agricultural products by fermentation, ultrapurification of the lactic acid by ultrafiltration, nanofiltration and/or electrodialysis, concentration of the lactic acid and production of a prepolymer, cyclizing depolymerization to dilactide, purification of the dilactide, ring-opening polymerization of the dilactide and demonomerization of the polylactide.