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:
Aug. 29, 1989
Filed:
Nov. 03, 1988
Applicant:
Inventors:
Assignee:
Polyplastics Co., Ltd., , JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528272 ; 528302 ; 528308 ; 5283083 ; 5283087 ; 528480 ; 526 88 ;
Abstract
A polyester having a high quality is produced by stirring its polycondensation reaction mixture in such a way that the stirring rate is reduced continuously in a stepwise manner corresponding to an increase in the melt viscosity as the reaction proceeds so that the stirring load is substantially constant after the viscosity of the reaction system has reached an arbitary value between 20 and 800 P until the completion of the reaction.