Patent Yard Sign in
Expired Canadian patentCanada

Electrode

CA 2050458 C · Owner: Hodgson, David R. · Inventors: Cairns, John F.; Hodgson, David R.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

An electrode which comprises a substrate of a valve metal or an alloy thereof having properties similar to those of the valve metal and a coating comprising an outer layer which comprises RuO2 an oxide, of at least one non-noble metal and at least one other noble metal or oxide thereof and an intermediate layer having a composition different from that of the outer layer and which comprises RuO2 and an oxide of at least one non-noble metal. The electrode is particularly useful as an anode for an electrolytic cell, eg a chlor-alkali cell, it has a lifetime therein which is greater than the sum of the operational life-times of electrodes which comprise a valve metal substrate and which …

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 August 30, 1991 and granted December 4, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 30, 2011.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 30, 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.
FiledAugust 30, 1991
GrantedDecember 4, 2001
Term endedAugust 30, 2011
Patent numberCA 2050458 C
Classification (IPC)C25B11/10 +1 more

Timeline

Timeline From CIPO dates

1992199419961998200020022004200620082010Application filedAug 30, 1991Patent grantedDec 4, 2001Term endedAug 30, 2011

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.