Process for extending the life of a displacement plating bath
CA 2193007 C · Owner: Reinbold, Carl W. · Inventors: Reinbold, Carl William; Dodd, John R.; Vitale, Americus C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A stabilized spray displacement tin plating process of copper printed circuit innerlayers is disclosed for the manufacture of multilayer printed circuit boards. During prolonged use of spray tin plating, the plating solution becomes saturated with cupurous thiourea complex which precipitates interfering with spray nozzles and other mechanical components. The tin plating solution is stabilized by removing portions from the reservoir before saturation is reached, selectively precipitating the thiourea complex, and returning the remaining solution back to the reservoir. The precipitated cupurous thiourea complex is redissolved in acid and either disposed of by conventional waste treatment or …
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 November 18, 1992 and granted May 9, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 18, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 18, 2014.
- 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.