Method and apparatus for extending material life in a bias transfer roll
CA 2082354 C · Owner: Pietrowski, Kenneth W. · Inventors: Gross, Robert A.; Pietrowski, Kenneth W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for extending the electrical life of a bias transfer roll is disclosed. The apparatus includes a biasing member comprising a bias roll member or other charging device for reversing current flow through the bias transfer roll. The apparatus of the present invention permits reversal of current flow through a bias transfer roll to replenish ions depleted therefrom during the transfer process.
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 November 6, 1992 and granted October 19, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 6, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 6, 2014.
- 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.