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, 1993
Filed:
Aug. 07, 1990
Hartmut Fischer, Hofheim am Taunus, DE;
Arnold Schneller, Mainz, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
Process for the preparation of an aromatic polyether in the presence of finely divided condensation auxiliaries. The process for the preparation of an aromatic polyether by condensation of the reactants in the presence of carbonates of metals of Group I of the Periodic Table, as condensation auxiliaries, employs the metal carbonates sodium carbonate or sodium bicarbonate or mixtures thereof in the form of very finely ground salts. The fine particle size distribution of the carbonate allows a significant shortening of the reaction times and permits polyethers having a defined degree of condensation to be reproducibly prepared.