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:
Nov. 27, 2001
Filed:
Jun. 07, 2000
Hyun Nam Cho, Seoul, KR;
Jae Min Hong, Seoul, KR;
Hyoung-Wook Lee, Kyungki-Do, KR;
Young Chan Ko, Seoul, KR;
Il Seok Choi, Kyungki-do, KR;
Korea Institute of Science and Technology, Seoul, KR;
Abstract
The present invention provides a process for preparing polyethylene naphthalate polymers comprising: esterifying a slurry comprising NDCA or a dicarboxylic acid containing NDCA or derivatives thereof, and ethylene glycol or a glycol containing ethylene glycol or derivatives thereof to produce esterification compounds comprising bis (beta-hydroxyethyl) naphthalate or low molecular weight polymers thereof, wherein one or more primary alcohol is added to the slurry; and polycondensing the above resultant esterification compounds to produce polyethylene naphthalate polymers. The process of the present invention allows for the preparation of a slurry more easily and to maximize the manufacturing efficiency. Ultimately, it is possible to increase the productivity of the PEN polymers and to obtain high quality PEN since the method of the present invention has an effect of minimizing side products of the polymerization by reducing the amount of ethylene glycol considerably and of shortening the reaction time of the esterification reaction.