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:
Jul. 28, 1998
Filed:
Nov. 24, 1997
Applicant:
Inventors:
Burkhard Kohler, Leverkusen, DE;
Duane B Priddy, Jr, Krefeld, DE;
Yun Chen, Krefeld, DE;
Harald Pielartzik, Krefeld, DE;
Robert-Joseph Kumpf, Dusseldorf, DE;
Assignees:
Bayer Aktiengesellschaft, Leverkusen, DE;
Bayer Corporation, Pittsburgh, PA (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528196 ; 528198 ;
Abstract
A process for the manufacture of cyclic oligocarbonate is disclosed. The process comprises a reaction of a bis-chlorocarbonic acid ester with isatinbisphenol or with a bis-chlorocarbonic ester thereof. The mixture of cyclic oligocarbonates thus prepared is useful as a precursor in the preparation of modified polycarbonate or polyester resins.