Incandescent mantles
CA 2047227 A1 · Owner: Edgar, John P. · Inventors: Edgar, John P.; Edgar, John P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An improved incandescent mantle which is stronger than mantles produced in the past as well as free of radioactive materials. The present invention provides a mantle comprised of zirconia yttria and erbia, which produces a resulting light output and color comparable for practical purposes to that of traditional thorium mantles. Although the invention is particularly adapted to mantles of inverted form, it is also applicable to other forms.
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 January 3, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 3, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 3, 2012.
- 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.