Chemical etchant for palladium
CA 2133134 C · Owner: American Telephone And Telegraph Company · Inventors: Maisano, Joseph John, Jr.; Straschil, Heinrich Karl; Abys, Joseph Anthony
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A cyanide based aqueous solution for stripping palladium from copper-containing substrate. The solution includes a cyanide radical source compound Na2CO3, a nitrobenzoic acid, NaOH, thallium compound an organo mercapto, compound, and water. The presence of the organo mercapto compound in thallium containing cyanide bath permits efficient stripping of palladium from copper containing substrates with minimum corrosion damage to the substrate.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed September 28, 1994 and granted December 15, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 28, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 28, 2016.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.