Method for preparing diaphragm for use in chlor-alkali cells
CA 2223858 C · Owner: Dilmore, Colonel R. Jr. · Inventors: Snodgrass, John O.; Dilmore, Colonel R. Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Asbestos-free diaphragms for chlor-alkali electrolytic cells are prepared by establishing a liquid permeable diaphragm base mat of fibrous synthetic polymeric material on the cathode structure providing a coating of inorganic , particulate material on the base mat and treating the coated base mat with a nonionic or anionic surfactant. Preferably the base mat is coated with the , inorganic particulate material using a slurry of the inorganic particulate material suspended in an alkali metal halide brine solution containing the surfactant.
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 23, 1996 and granted May 1, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 23, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 23, 2018.
- 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.