Magnetic head and method of manufacturing thereof
CA 1294039 C · Owner: Ishihara, Kousou · Inventors: Shimizu, Yoshiaki; Ino, Kazuo; Okuda, Hiroyuki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A magnetic head comprises a pair of magnetic core halves, heat-resistant thin films and ferromagnetic thin films, the pair of magnetic core halves being opposed to each other through a non-magnetic material such as SiO2 to form a magnetic gap. The magnetic core halves are made of a ferromagnetic oxide such as ferrite and have gap forming faces to be opposed to each other to form the magnetic gap. The gap forming faces are etched by phosphoric acid solution and then purified by reverse sputtering so that, a grown crystal of the ferromagnetic oxide is exposed on the gap forming faces. A heat-resistant thin film of a heat-resistant material such as SiO2 is formed on each of the gap forming …
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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 January 7, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 7, 2009.
- 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.