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. 30, 1977
Filed:
Oct. 24, 1975
Sumitomo Chemical Company, Limited, Osaka, JA;
Abstract
A process for producing 1-nitroanthraquinone with high purity which comprises treating crude 1-nitroanthraquinone containing as the main impurities dinitroanthraquinones and .beta.-nitroanthraquinone with an alkali sulfite in an aqueous medium under heating and which is characterized in that the crystals of the crude 1-nitroanthraquinone are pulverized by the aid of a pulverizer, a fine pulverizer or an ultra-fine pulverizer prior to and/or during the treatment with the aqueous alkali sulfite; and a process for producing 1-aminoanthraquinone which comprises subjecting the reaction mixture obtained by the said treatment with the alkali sulfite solution mentioned above, if necessary after further fine pulverization, to a reaction with a reducing agent, or ammonia or an aliphatic or aromatic amine.