Expired Canadian patentCanada
Process of grinding and polishing plates of glass
CA 252195 A · Owner: The Pilkington Brothers · Inventors: Frederic Barnes Waldron
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordRead 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
- Granted July 28, 1925. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 28, 1942.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Filed—
GrantedJuly 28, 1925
Term endedJuly 28, 1942
Patent numberCA 252195 A
Classification (IPC)B24B7/20
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.