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. 20, 1980
Filed:
Apr. 23, 1976
Fumiyuki Suzuki, Minami-ashigara, JP;
Toshimitu Okutu, Minami-ashigara, JP;
Keitaro Ohe, Minami-ashigara, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A process for preparing bis(hydroxyethyl)terephthalate and its low molecular weight oligomers in a reactor equipped with a rectifying column which comprises suspending or dissolving terephthalic acid in molten bis(hydroxyethyl)terephthalate and its low molecular weight oligomers at a temperature above the dew point of ethylene glycol and feeding gaseous or liquid ethylene glycol into the suspension or the solution to react it with the terephthalic acid, where the amount of ethylene glycol fed into the reactor is controlled so as to maintain the temperature inside the rectifying column at a temperature at which the ethylene glycol does not substantially distill off from the rectifying column and the partial pressure of the ethylene glycol is maximized.