Process for preparing anhydride-grafted polymers with improved colour
CA 2400357 A1 · Owner: Wong, Chun Sing · Inventors: Wong, Chun Sing
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
There is provided a process for improving the colour of anhydride-grafted polymers. The process includes the steps of admixing in an extruder a polyolefin, a free radical initiator, and an anhydride-providing monomer at a temperature above the melting point of the polyolefin adding an effective , amount of an oxo-boron compound to the admixture; and extruding the resultant anhydride-grafted polymer into a shaped article.
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 July 20, 2001. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 20, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 20, 2023.
- 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.