Apparatus and method for cooling an extruded blown film
CA 2088718 A1 · Owner: The Boc Group, Inc. · Inventors: Kirschner, Mark J.; Lee, Ron C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Apparatus and method for cooling an extruded blown film in which the interior surface of the thin film bubble is contacted with a gas which does not contain water vapor to thereby cool the extruded film. The apparatus and method may employ an enclosed circulation system to provide for the reuse of the gas through cooling with a liquid coolant such as liquid cryogen.
Read the whole patent
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 February 3, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 3, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 3, 2015.
- 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.