Method and apparatus for delivering molten polymer to an extrusion die
CA 2070829 A1 · Owner: Exxon Chemical Patents Inc. · Inventors: Fetcko, John Thomas; Allen, Martin Anthony
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A polymer melt delivery system comprises a preheated hopper a, high clearance auger, a gear pump, and means for delivering heat to the polymer. The resin is melted and fed to the auger and pumped to the gear pump and further pumped to an extrusion die. Heat is added to the polymers from the hopper and throughout its course to the outlet connection for the extrusion die. The preheater in the hopper includes heat conductive fins. The system is particularly suited for use in combination with a melt-blowing die.
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 November 29, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 29, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 29, 2012.
- 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.