Multilayer film with polyolefin and polyvinyl chloride
CA 2337834 C · Owner: Wofford, George D. · Inventors: Roberts, William P.; Wofford, George D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A film includes a first layer including polyvinyl chloride; and a second layer including a material such as anhydride functionalized polyolefin, ethylenelvinyl acetate copolymer having a vinyl acetate content of between 10 % and 35 %, ethylene/alkyl acrylate copolymer having an alkyl acrylate content of between 10 % and 30 % ethylenelalkyl , methacrylate copolymer having an alkyl methacrylate content of between 10 % and 30 %, ethylene/acrylic acid copolymer having an acrylic acid content of between 10 % and 30 %, ethylene/methacrylic acid copolymer having a methacrylic acid content of between 10 % and 30 % and , ionomer. A layer of polyolefin, and/or an additional layer including any of …
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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 July 12, 1999 and granted November 4, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 12, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 12, 2021.
- 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.