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:
Jan. 19, 1999
Filed:
Aug. 04, 1997
Applicant:
Inventors:
Shunya Shinohara, Shinnanyo, JP;
Sadakatsu Kumoi, Hikari, JP;
Assignees:
Tosoh Corporation, Shinnanyo, JP;
Delamine bv, Amersfoort, NL;
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
564498 ; 564497 ;
Abstract
The invention provides a method of industrially producing high-quality polyethylenepolyamines, which exerts high decolorizing effect and is economical, comprising the steps that hydrogen halide is added to a mixture of polyethylenepolyamines and heated, then distillation is performed to fractionate components each having a boiling point not higher than that of triethylenetetramine, next alkali metal hydroxide is added to that residual liquor after distillation to neutralize, and distillation is performed again to fractionate components each having a boiling point not lower than that of tetraethylenepentamine.