Production of grain-oriented silicon steel sheets having an insulating film formed thereon
CA 2020285 C · Owner: Nippon Steel Corporation · Inventors: Minematsu, Eisuke; Hirose, Kikuji; Tanaka, Osamu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for forming an insulating film on a grain-oriented silicon steel sheet by applying an insulating coating solution comprising 100 parts by weight (calculated as the solid component) of a mixture of colloidal substances, composed of50 to 98 weight % (calculated as the solid component Sio2) of colloidal silica having a partical diameter not larger than 50 nano m, and 2 to 50 weight % (calculated as the solid component) of at least one colloidal substance having a particle diameter ranging from 80 to 3000 nano m, selected from the group consisting of oxides, carbides, nitrides, sulfides, borides hydroxides, silicates, carbonates, borates sulfates, nitrates and, chlorides of Fe Ca, Ba, …
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 July 3, 1990 and granted September 13, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 3, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 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.