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. 18, 1977
Filed:
Dec. 16, 1975
Mitsui Toatsu Chemicals Incorporated, Tokyo, JA;
Abstract
A process for preparing 1-aminoanthraquinone having high purity, which comprises either 1. hydrogenating 1-nitroanthraquinone in an aqueous medium in the presence of a base using a hydrogenating catalyst, and then oxidizing the hydrogenation product, or 2. hydrogenating crude 1-nitroanthraquinone containing dinitroanthraquinones as impurities or crude 1-aminoanthraquinone containing diaminoanthraquinones as impurities in an aqueous medium in the presence of a base using a hydrogenating catalyst, stopping the hydrogenation at a time when the 1-nitroanthraquinone or 1-aminoanthraquinone has been substantially reduced to 1-aminoanthrahydroquinone but the dinitroanthraquinones or diaminoanthraquinones remain substantially unreduced to diaminoanthrahydroquinones, removing water-insoluble materials from the reaction mixture, and then oxidizing the remaining water-soluble residue.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile