Method of producing zinc oxide whiskers
CA 2007388 C · Owner: Asakura, Eizo · Inventors: Miyoshi, Ichiro; Yoshinaka, Minoru; Shintaku, Yasuyuki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is directed to a method of producing zinc oxide whiskers, wherein zinc powder particles coated with oxide layers are heated in an inert gas so that zinc vapor may be desirably generated. The zinc vapor is then brought into contact with oxygen gas or oxygen-containing gas for oxidization. In this way zinc, oxide whiskers are obtained, each of which has a nuclear portion and four needle-like crystal portions extending from the nuclear portion in four different directions.
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 9, 1990 and granted February 16, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 9, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 9, 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.