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:
Oct. 29, 2013
Filed:
Aug. 03, 2010
Neil Gregory Pschirer, Mainz, DE;
Jianqiang Qu, Ludwigshafen, DE;
Martin Koenemann, Mannheim, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
A process for preparing a rylenetetracarboxylic dianhydride, or a salt thereof having application formula Ib by subjecting a rylenetetracarboximide of application formula II to a hydrolysis under alkaline conditions in the presence of a polar organic solvent and removing the rylenetetracarboxylic dianhydride Ib from any rylenetetracarboxylic monoimide monoanhydride of application formula Ia which is formed to form the rylenetetracarboxylic dianhydride, or the salt thereof having formula Ib; or hydrolyzing the rylenetetracarboximide of application formula II under conditions that form the compound of application formula Ib and substantially no rylenetetracarboxylic monoimide monoanhydride of application formula Ia.