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:
Jun. 07, 1994
Filed:
Mar. 19, 1992
Herman P Benecke, Columbus, OH (US);
Alex Cheung, Ft. Collins, CO (US);
George E Cremeans, Groveport, OH (US);
Melville E Hillman, Hillard, OH (US);
Edward S Lipinsky, Worthington, OH (US);
Richard A Markle, Columbus, OH (US);
Richard G Sinclair, Columbus, OH (US);
BioPak Technology, Ltd., Golden, CO (US);
Abstract
Disclosed is a method for producing cyclic esters by the conversion of hydroxy carboxylic acids and their derivatives to their respective cyclic esters. Such cyclic esters, including lactide or glycolide, are particularly useful for producing polymers which can be used to make biodegradable materials, such as biodegradable packaging material. Various methods of cyclic ester production are disclosed, including liquid phase and vapor phase reactions. Also disclosed are various methods for recovering cyclic esters from product-containing streams.