Machinable lead-free copper alloys and additive and method for making the alloys
CA 2224679 C · Owner: Li, Taie · Inventors: King, Michael G.; Li, Taie
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Machinable lead free brasses for potable water applications are provided wherein a combination of bismuth and selenium are substituted in the alloy for lead and the bismuth and selenium are added to the alloy in the form of an additive product comprising bismuth selenide. A method of making the brasses which meets environmental and safety regulations is also provided. The bismuth selenide is preferably made by sintering particles of bismuth and selenium in a Bi/Se weight ratio of about 1.8 or greater and fusing the sinter.
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 June 13, 1996 and granted August 28, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 13, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 13, 2018.
- 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.