Title:
PRODUCTION OF POLYESTER
Document Type and Number:
Japanese Patent JP2000178352
Kind Code:
A
Abstract:
To provide a process for producing a cheaper polyester, wherein a germanium compound distilled off during the polycondensation reaction is recovered in high yields and is reused as the polycondensation catalyst.
A process for producing a polyester is provided which comprises effecting the polycondensation reaction by using germanium dioxide as the catalyst, concentrating the reaction distillate formed as the reaction proceeds by distillation, and reusing the germanium compound contained in the concentrated solution after being purified. The germanium compound reused can be obtained through a step of depolymerizing the oligomer in the concentrated solution with ethylene glycol and a step of purification.
Inventors:
MURATA KAZUO
MURAI MASUO
OZAWA FUMIO
SHIBABUCHI NORIKO
NAKAZONO TOSHIYUKI
KITANO MASAKAZU
MURAI MASUO
OZAWA FUMIO
SHIBABUCHI NORIKO
NAKAZONO TOSHIYUKI
KITANO MASAKAZU
Application Number:
JP35445098A
Publication Date:
June 27, 2000
Filing Date:
December 14, 1998
Export Citation:
Assignee:
NIPPON ESTER CO LTD
International Classes:
C08G63/183; C08G63/85; C08G63/88; (IPC1-7): C08G63/85; C08G63/183; C08G63/88
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