Phosphate chemical treatment method
CA 2112592 C · Owner: Nippondenso Co. Ltd. · Inventors: Matsuda, Shigeki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is a method of forming a phosphate chemical treatment film which is efficient and allows a high-quality chemical film to be obtained by, which a substance to be treated is subjected to electrolytic treatment while removing the sludge which, consists of impurities other than the unavoidable impurities in the phosphate chemical treatment bath. According to this method an adequate phosphate chemical, treatment film may be formed onto any type of metal material, to provide phosphate chemical treatment films having thicknesses not obtainable by the prior art.
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 April 30, 1993 and granted May 21, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 30, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 30, 2015.
- 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.