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:
Mar. 24, 1981
Filed:
Mar. 22, 1979
Applicant:
Inventors:
Ryo Matsuura, Yamato, JP;
Kazuaki Sakai, Fujisawa, JP;
Tuneyasu Sato, Chigasaki, JP;
Yorinobu Yamada, Kawasaki, JP;
Kowzo Bandow, Kawasaki, JP;
Assignee:
Kawasaki Kasei Chemicals Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
B01D / ; C07C / ;
U.S. Cl.
CPC ...
203 31 ; 203 33 ; 203 34 ; 203 38 ; 203 43 ; 203 91 ; 2603 / ;
Abstract
A crude naphthoquinone produced by an oxidation of naphthalene is purified by a reduced pressure distillation of a crude 1,4-naphthoquinone having an acid content of less than 5 equivalent % calculated as monobasic acid and the crude naphthoquinone is preferably treated by an oxidation of oxidizable impurities.