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:
Feb. 07, 1995
Filed:
Nov. 03, 1992
Masafumi Moriya, Iwakura, JP;
Kazuo Hosoda, Katsushika, JP;
Masatoshi Yoshida, Katsushika, JP;
Masayoshi Tsukanome, Katsushika, JP;
Miyoshi Yushi Kabushiki Kaisha, Tokyo, JP;
Abstract
Metal scavengers suitable for use in the treatment of waste water are disclosed. The metal scavengers individually comprise a polyamine derivative and a polyethyleneimine derivative. The polyamine derivative is formed of a polyamine having a molecular weight not higher than 500 and contains, per molecule of the polyamine, at least one dithiocarboxyl group or a salt thereof as an N-substituting group substituted for an active hydrogen atom of the polyamine such that at least 30% of suitable active hydrogen atoms contained in the polyamine are substituted by the dithiocarboxyl group or salt thereof. The polyethyleneimine derivative is formed from a polyethyleneimine having an average molecular weight of at least 5,000 and contains, per molecule of the polyethyleneimine, at least one dithiocarboxyl group or a salt thereof as an N-substituting group substituted for an active hydrogen atom of the polyethyleneimine such that at least 40% of substitutable active hydrogen atoms contained in the polyethyleneimine are substituted by the dicarboxyl group or a salt thereof. The mixing ratio of the polyamine derivative to the polyethyleneimine derivative is about 9-7:1-3 by weight.