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:
Nov. 09, 1999
Filed:
Nov. 06, 1997
Masamichi Mizukami, Tsukuba, JP;
Yoshihisa Arai, Tsukuba, JP;
Hidefumi Harada, Tsukuba, JP;
Takuo Ohshida, Tsukuba, JP;
Hiroaki Ohgi, Tsukuba, JP;
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Abstract
A process for producing diaryl carbonate which comprises (A) a step for producing dialkyl carbonate represented by the general formula RO--CO--OR by reacting urea with alkyl alcohol represented by the general formula ROH, (B) a step for producing both alkyl aryl carbonate represented by the general formula RO--CO--OAr and diaryl carbonate represented by the general formula ArO--CO--OAr by reacting dialkyl carbonate produced in the above step (A) with an aromatic hydroxy compound represented by the general formula ArOH, and (C) a step for producing diaryl carbonate represented by the general formula ArO--CO--OAr by allowing to conduct disproportionation reaction of unreacted alkyl aryl carbonate produced in the above step (B), wherein R shows an alkyl group and Ar shows a non-substituted phenyl group or a phenyl group substituted by alkyl group, alkoxy group, aryl group, aryloxy group or halogen.