Polyurethane, process for its production and polyester diol used for its production
CA 2015488 C · Owner: Kuraray Co. Ltd. · Inventors: Tsuda, Tomoyasu; Hirai, Koji; Komiya, Yukiatsu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is directed to a polyurethane comprising (A) a structural unit derived from polyester diol, which consists essentially of 1 to 3 members selected from the structural units (I), (II) and (III) shown below and the structural units (IV) and (V) shown below the, molar fractions of these structural units satisfying specific relationships:, (I) , wherein m represents an integer of 8 to 10 (II) : , (III) : -O-R1-O-, wherein R1 represents a branched primary glycol residue having 4 to 8 carbon atoms, (IV) : , (V) : wherein n represents an integer of 4 to 8 and (B) a, structural unit derived from a diisocyanate; a process for producing the same; and the polyester diol used for …
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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 April 26, 1990 and granted July 8, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 26, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 26, 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.