Seamless master and method of making same
CA 2678281 C · Owner: Wang, San Zhuang · Inventors: Savant, Gajendra D.; Wang, San Zhuang; Kaiser, Ed
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Hollow, cylindrical, seamless metal master (604) for producing seam-less diffuser sheets of preselected length and width. Additional aspects of the invention include a hollow cylindrical seamless invertable elastomeric master (402) and method of making the same and an apparatus and process for effecting variable diffuser record-ing in photosensitive medium.
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 29, 2001 and granted February 14, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 29, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 29, 2023.
- 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.