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:
Apr. 17, 1990
Filed:
Mar. 23, 1989
Applicant:
Inventors:
Shigeo Kondoh, Osaka, JP;
Toshikazu Umemura, Osaka, JP;
Assignee:
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528483 ; 264340 ; 264345 ; 528196 ;
Abstract
A method for producing a purified polycarbonate resin is disclosed, comprising contacting a solid polycarbonate resin with a fluid comprising at least 70% by weight of carbon dioxide and having a temperature of 30.degree. to 120.degree. C. and a pressure of at least 10 kg/cm.sup.2. The method can effectively remove almost all the impurities contained in the polycarbonate resin within a very short period of time, thereby providing highly purified polycarbonate resin materials which are suitably used in the fields of information, electronic and medical industries.