Expired Canadian patentCanada
Incandescent lamp containing additive to reduce filament sag
CA 1190590 A · Owner: Gte Products Corporation · Inventors: Shaffer, John W.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Filament sag in tungsten-halogen lamps is significantly reduced by including within the envelope an additive selected from the group of bismuth, antimony and tellurium and combinations thereof.
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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
- Granted July 16, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 16, 2002.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledApril 14, 1983
GrantedJuly 16, 1985
Term endedJuly 16, 2002
Patent numberCA 1190590 A
Classification (IPC)H01K1/04 +2 more
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.