Silicon nitride sintered body and method of producing the same
CA 2036010 C · Owner: Ngk Insulators, Ltd. · Inventors: Sakai, Hiroaki; Isomura, Manabu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A dense silicon nitride sintered body having an excellent strength at high temperatures as well as at room temperature and a method of preparing it are disclosed. The body consists essentially of Si3N4 as a main component the remainder being at, least one rare earth element compound SiC and at least one, compound of tungsten or molybdenum. The grain boundary phase of Si3N4 grains consists substantially of crystal phases. The body is prepared by combining Si3N4 powder, a rare earth element oxide powder, and SiC powder, and a powder of at least one compound of W or Mo, forming the raw material into a shaped body and, firing the shaped body in N2 atmosphere to substantially crystallize the …
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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 February 8, 1991 and granted July 16, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 8, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 8, 2013.
- 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
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.