Filters for light metals
CA 2136335 C · Owner: Swift, Martin S. · Inventors: Swift, Martin S.; Jones, David L.; Stoetzel, Reinhard
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Filters for filtering molten light metals comprise a reticular foam formed from a composition comprising graphite wollas-, tonite, silica and a borosilicate glass and consist of a crystalline phase comprising graphite and wollastonite dispersed in a substantially amorphous matrix of botosilicate glass. The filters can readily be machined accurately from large pieces of the filter material and they do not pick up moisture from the atmosphere when stored. The borosilicate glass used to produce the filters preferably has a softening temperature (T1) in the range of 600 °C more preferably 650 °C to 900 °C and a melting temperature (T2) in the range of 700 °C to 1100 °C as measured , …
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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 May 10, 1993 and granted January 28, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 10, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 10, 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.