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. 13, 2014
Filed:
Dec. 16, 2010
Shigeru Suzuki, Tokyo, JP;
Kazuyuki Yamane, Tokyo, JP;
Masaru Kagoshima, Tokyo, JP;
Michio Kikuchi, Tokyo, JP;
Shigeru Suzuki, Tokyo, JP;
Kazuyuki Yamane, Tokyo, JP;
Masaru Kagoshima, Tokyo, JP;
Michio Kikuchi, Tokyo, JP;
Kureha Corporation, Tokyo, JP;
Abstract
A method for producing glycolide, including the steps of: heating a mixture containing a glycolic acid oligomer, a high-boiling point polar organic solvent having a boiling point of 230 to 450° C., and a tin compound under normal pressure or reduced pressure until a temperature at which the glycolic acid oligomer is depolymerized, to thereby dissolve the glycolic acid oligomer in the high-boiling point polar organic solvent; heating a solution, in which the glycolic acid oligomer is dissolved, under normal pressure or reduced pressure until a temperature at which the glycolic acid oligomer is depolymerized, to thereby form glycolide by depolymerization of the glycolic acid oligomer in the solution; and co-distilling off the high-boiling point polar organic solvent and the formed glycolide from a depolymerization reaction system.