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.

Date of Patent:
Feb. 13, 1979

Filed:

Mar. 13, 1978
Applicant:
Inventors:

Ryuichi Yamamoto, Omuta, JP;

Yutaka Hirai, Omuta, JP;

Teruyuki Nagata, Omuta, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
260575 ; 260705 ;
Abstract

A process for purifying crude p-aminophenol which contains 4,4'-diaminodiphenyl ether and other impurities, which process comprising adding an alkali metal compound to the crude p-aminophenol in an aqueous medium in an atmosphere of an inert gas and, if necessary, in the presence of a reducing agent to give an aqueous solution of an alkali metal salt of p-aminophenol, and contacting the aqueous solution with an inert organic solvent immiscible with water to permit 4,4'-diaminodiphenyl ether and other impurities to be separated by extraction in the solvent.


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