Reduced curl battery separator and method
CA 2252143 A1 · Owner: Oxley, Jeffery Allen · Inventors: Danko, Thomas; Oxley, Jeffery Allen
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A curl resistant battery separator of a noncellulosic nonwoven substrate extrusion coated on at least one surface with a cellulose film and process for making such separator by contacting a nonwoven noncellulosic textile substrate with a cellulose or cellulose derivative solution on at least one side of said substrate; converting the solution to a solid cellulose or cellulose derivative, preferably having a degree of polymerization of at least 350 more, preferably at least 600, to form a coated substrate; washing said substrate in an aqueous solution; drying the coated substrate under biaxial tension to provide a battery separator having a moisture content of from about 4 to 25 wt. % based …
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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 October 27, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 27, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 27, 2020.
- 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.