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:
Aug. 04, 1992
Filed:
Dec. 02, 1991
Joseph A Abys, Warren, NJ (US);
Igor V Kadija, Ridgewood, NJ (US);
Joseph J Maisano, Jr, Denville, NJ (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
This invention embodies a process for synthesizing electrodialythically palladium ammine hydroxide for use in palladium plating baths. The electrodialysis takes place in a cell with a catholyte, a product and an anolyte compartments which are divided by a fluorinated anion permselective membranes. Catholyte solution readily supplies OH ions, raw starting solution contains palladium ammine ions and anions capable of migrating into the anolyte compartment, and anolyte solution readily absorbs the anions from the raw solution. Electrodes, placed in the outer compartments, are placed no more than 5 cm apart. The process is conducted with current densities of 500 ASF or less, with 200 ASF being preferable, with current efficiencies of 50 to 90 percent, with 60-80 percent being preferable, and at bath temperatures of from above freezing to 40.degree. C., with 25.degree.-40.degree. C. being preferable. The electrodialysis results in a stable palladium diammine hydroxide solution containing a small fraction of starting palladium diammine compound, such as palladium diammine chloride, making the final solution readily useable either as a replenishing or a plating solution.