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:
Mar. 26, 1996
Filed:
Nov. 15, 1994
Applicant:
Inventors:
Hans-Josef Buysch, Krefeld, DE;
Joachim Dohm, Ko/ ln, DE;
Carsten Hesse, Krefeld, DE;
Johann Rechner, Krefeld, DE;
Dieter Kaufmann, Goslar, DE;
Assignee:
Bayer Aktiengesellschaft, Leverkusen, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
558270 ; 558271 ; 558274 ; 558275 ;
Abstract
Diaryl carbonates can be prepared by reacting aromatic hydroxy compounds with CO and O.sub.2 at elevated temperature over a noble metal catalyst in the presence of a base, a quaternary salt, a cocatalyst and a dessicant. According to the invention, the noble metal catalyst is activated with CO in the presence of the quaternary salt and optionally in the presence of the cocatalyst. In a particular process variant, the base used is a preformed alkali metal phenoxide.