Solid elastomeric block copolymers
CA 2074624 C · Owner: Matthews, Demetreos Nestor · Inventors: Loveless, Frederick Charles; Coolbaugh, Thomas Smith; Matthews, Demetreos Nestor
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
There are disclosed novel, solid, elastomeric block copolymers with improved resistance to cold flow wherein either 1) the terminal blocks are polymers of at least one conjugated diene I e.g. isoprene, which, contains at least five carbon atoms with at least one of each pair of double-bonded carbon atoms in the polymerized diene I units being additionally single-bonded to two carbon atoms at least one middle or, interior block is a polymer of butadiene and at least one middle or, interior block is a polymer of at least one aryl-substituted olefin e.g. styrene; or 2) the terminal blocks are random copolymers of at least one diene I as previously defined and butadiene and at least, one middle …
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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 July 24, 1992 and granted September 23, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 24, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 24, 2014.
- 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.