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. 06, 2003
Filed:
Sep. 13, 2001
Applicant:
Inventors:
Assignee:
Inventa-Fischer GmbH & Co. KG, Berlin, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B29D 2/200 ; C08F 2/000 ;
U.S. Cl.
CPC ...
B29D 2/200 ; C08F 2/000 ;
Abstract
The invention relates to a method for producing polyesters with a reduced content of free acetaldehyde from terephthalic acid and ethylene glycol via a catalyzed polycondensation in the melt and also the use of this method. The method is based thereby on the usage of highly active polycondensation catalysts, on the deactivation of these catalysts by the addition of phosphorous-containing inhibitors and the addition of acetaldehyde-bonding substances. The entire polycondensation is thereby implemented at temperatures beneath 280° C.