Nonwoven fabric having a pore size gradient and method of making same
CA 2249331 A1 · Owner: Varona, Eugenio Go · Inventors: Varona, Eugenio Go
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Methods and apparatus for forming a nonwoven fiber web containing a pore size gradient resulting in enhanced wicking properties. A first method utilizes a conventionally formed web having an average pore size and comprises selectively contacting the web with a heat source to shrink the fibers in selected areas. The smaller pore sizes have greater wicking ability. A second method utilizes a novel apparatus and comprises forming a nonwoven fiber web having zones of fibers, each zone having generally an average set of fiber structure and/or composition, the zones preferably overlapping. The zones of fibers are exposed to a heat source, which shrinks the fibers according to their …
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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 April 8, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 8, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 8, 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.