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. 16, 1999
Filed:
Dec. 10, 1997
Applicant:
Inventors:
Recai Sezi, Roettenbach, DE;
Eberhard Kuehn, Hemhofen, DE;
Hellmut Ahne, Roettenbach, DE;
Sueleyman Kocman, Forchheim, DE;
Assignee:
Siemens Aktiengesellschaft, Munchen, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G / ; C08G / ;
U.S. Cl.
CPC ...
528327 ; 528125 ; 528172 ; 528173 ; 528174 ; 528337 ; 528352 ; 528353 ; 528373 ; 528377 ;
Abstract
In a method of synthesis of polybenzoxazole and polybenzothiazole precursors, a dicarboxylic acid or a dicarboxylaic acid ester is reacted with a bis-o-aminophenol or bis-o-aminothiophenol in a suitable solvent in the presence of an activating reagent having the following structure: ##STR1##