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:
Oct. 10, 1995
Filed:
Jul. 21, 1994
Applicant:
Inventors:
Katsushige Hayashi, Ibaraki, JP;
Mitsuhiko Masumoto, Ibaraki, JP;
Masayuki Nakajima, Ibaraki, JP;
Takuya Hasaki, Ibaraki, JP;
Masahiko Ishikawa, Ibaraki, JP;
Atsushi Hirashima, Ibaraki, JP;
Assignee:
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528196 ; 525468 ; 528198 ; 528200 ;
Abstract
A process for preparing a polycarbonate which comprises performing a transesterification and a polycondensation reaction with a diarylcarbonate and dihydroxyaryl compound, in a reaction apparatus composed of stainless steel comprising at least 12% by weight of Ni, and at least 22% by weight of Cr, and having Fe as the remaining main component. A polycarbonate which has a good color, is stable to hydrolysis and resistant to heat-yellowing is the resulting product.