Apertured films having durable wettability and processes for making them
CA 2265713 A1 · Owner: Wu, Lanying · Inventors: Lee, Yann-Per; Wu, Lanying; Holzwarth, Ronald Bernd
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to a process for forming a single-layer durably , wettable polymeric web having a plurality of apertures. This process comprises melting a mixture of at least one thermoplastic polymer and at least one migratable surfactant and extruding the mixture to form a single-layer substantially continuous polymeric film. The film is then apertured using high pressure fluid flows. Aperture formation is conducted when the single-layer polymeric film has a contact angle of at least about 30~ to minimize wash-off , of the surfactant impregnated in the polymer web. The invention also relates to durably-wettable apertured webs.
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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 September 10, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 10, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 10, 2019.
- 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.