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. 11, 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
Apparatus and methods for removing polyvalent by-product anions, e.g. borate and orthophosphate ions, from electroless metal plating baths employing borane or hypophosphite reducing agents and typically comprising monovalent anions or neutral zwitterions as metal chelant and/or counterion. The apparatus and methods of this invention employ (a) solvent extraction to remove metal species for recycle, (b) anion filtration to separate polyvalent anions from neutral zwitterions and monovalent anions and (c) ion exchange units to remove metal and metal chelant species from polyvalent anion-containing waste streams.