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:
Aug. 02, 1977
Filed:
Nov. 14, 1975
Applicant:
Inventors:
Wilfried Sahm, Kelkheim, Taunus, DT;
Erich Schinzel, Hofheim, Taunus, DT;
Gunter Rosch, Altenhain, Taunus, DT;
Assignee:
Hoechst Aktiengesellschaft, Frankfurt am Main, DT;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
2603 / ; 25230128 ; 25230124 ; 542432 ; 26034622 ; 26034671 ;
Abstract
Condensation of a benzofuran, which is substituted in 2-position by a carboxylic acid hydrazide group bound to the benzofuran nucleus via a bridgemember being in conjugation with the double bonds of the benzofuran, with a benzofuran-2-carboxylic acid halide yields a bisacyl hydrazide which is capable of oxdiazol ring closure while splitting off water. The so-obtained oxdiazoles are optical brighteners, especially for polyester materials.