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:
Sep. 16, 2014
Filed:
Jun. 17, 2011
Jin-eok Kim, Daejeon, KR;
Seoung-il Kim, Daejeon, KR;
Han Jin Kwag, Daejeon, KR;
Sang Hee Park, Daejeon, KR;
Jin-Eok Kim, Daejeon, KR;
Seoung-IL Kim, Daejeon, KR;
Han Jin Kwag, Daejeon, KR;
Sang hee Park, Daejeon, KR;
Abstract
Provided is a method for preparing 4,4'-dinitrodiphenylamine (4,4′-DNDPA) in high yield via the NASH reaction using a mixture of a bis-quaternary ammonium base and a base catalyst for the reaction of urea with nitrobenzene, and a method of preparing 4,4′-bis(alkylamino)diphenylamine (4,4′BAADA) in high yield and purity by hydrogenating the resulting 4,4′-DNDPA with a ketone in the presence of hydrogen and hydrogenation catalyst. The catalyst complex used in the present invention allows easy recovery, provides superior alkaline stability and is capable of reducing production cost.