Liquid-resistant paperboard tube, and method and apparatus for making same
CA 2390337 A1 · Owner: Sonoco Development, Inc. · Inventors: Huffer, Scott W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A paperboard tube is rendered resistant to liquid by coating portions or all of, the tube with submicron-sized particles of inorganic material that are treated to be, hydrophobic and/or oleophobic. The particles can be applied directly to the paperboard, lodging in surface pores such that the particles adhere to the paperboard. Alternatively, a light coating of a tacky binder or adhesive can first be applied to the, paperboard and then the particles can be applied such that they adhere to the binder. Preferably, the particles have a large surface area per gram; in one embodiment, for, instance, silica particles are employed having a surface area of about 90-130 m2/g. As, a result, …
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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 June 10, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 10, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 10, 2024.
- 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.