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:
Jul. 12, 1994
Filed:
Mar. 09, 1993
Applicant:
Inventors:
Nicholas M Martyak, Ballwin, MO (US);
Bruce F Monzyk, Maryland Heights, MO (US);
Henry H Chien, St. Louis, MO (US);
Assignee:
Monsanto Company, St. Louis, MO (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
B01D / ;
U.S. Cl.
CPC ...
210638 ; 210259 ; 210652 ;
Abstract
Apparatus and methods for removing formate ions from electroless metal plating baths employing formaldehyde as a reducing agent and typically comprising polyvalent anions as metal chelant and/or counterion. The apparatus and methods employ anion filtration to separate polyvalent anions from monovalent formate ions and ion exchange units to remove metal and metal chelant species from formate-containing streams. Preferred aspects of this invention provide apparatus and methods for removing formate from electroless copper plating baths.