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:
Apr. 26, 1994
Filed:
Nov. 20, 1992
Nicholas M Martyak, Ballwin, MO (US);
Bruce F Monzyk, Maryland Heights, MO (US);
Henry H Chien, St. Louis, MO (US);
Monsanto Company, St. Louis, MO (US);
Abstract
Sulfate-free electroless copper baths comprising cupric ions, formaldehyde, formate ions, hydroxyl ions, a copper counterion, e g. preferably a monovalent anion such as acetate, nitrate or formate, and copper chelant such as an alkali metal salt of aminotris(methylenephosphonic acid), biscarboxymethylaspartic acid, ethylenediaminetetra(methylenephosphonic acid), diethylenetriaminepenta(methylenephosphonic acid), gluconic acid, 1-hydroxyethylidene-1,1-diphosphonic acid, mucic acid, D-saccharac acid, tartaric acid and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine are amenable to the recovery of copper, e.g. from purge streams, using the methods and apparatus including solvent extraction, e.g. employing hydroxamic acid extractants, anion filtration, ion-exchange and chelant precipitation.