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:
Sep. 16, 1986
Filed:
Nov. 19, 1985
Applicant:
Inventors:
Assignees:
Mitsubishi Rayon Co., Ltd., both of, JP;
Research Association for Synthetic Fiber Technology, both of, JP;
Primary Examiner:
Int. Cl.
CPC ...
C08G / ; C08G / ;
U.S. Cl.
CPC ...
528274 ; 5283081 ; 5283083 ; 528483 ; 528501 ;
Abstract
A process for the production of polyester comprising at least 80% of an ethylene terephthalate repeating unit using as a starting material an ester compound made mainly of terephthalic acid and ethylene glycol or an oligomer thereof is disclosed. This process is characterized in that a prepolymer having an intrinsic viscosity of not more than 0.4 dl/g and a carboxyl terminal group concentration [COOH] of not more than 90.times.[.eta.].sup.-0.4 .mu.eq/g is fed to a final polymerization unit and polymerized in the form of a molten thin film having a thickness of from 0.005 to 0.15 mm.