Polyurethanes
CA 2012469 C · Owner: Kim, Soonih · Inventors: Kim, Soonih; Kimura, Yoshiharu; Nishiura, Akio
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A polyurethane (I) of 1000 to l00000 in molecular weight, comprising plural segments, which are each structural units of A-B, A-C and A-D of the formulae: (See fig. I), (See fig. II) and, (See fig. III) the molar proportion of the said segments of A-B A-C and, A-D i.e. x : y : z being 0.01 to 0.8 : 0 to 0.80 : 0 to o.99, provided that the sum of x, y and z is 1.0; wherein R1 is a skeleton of a diisocyanate aza is a group of the formula:, (See fig. IV) or (See fig. V), wherein Y1 and Y2 represent oxygen imino (-NH-), and hydrocarbon derivatives thereof; R4 and R5 are optional substituents;, R2 is a polyalkylene glycol residue; Z is oxygen or imino;, R3 is alkylene or the residue of an ether …
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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 March 19, 1990 and granted May 12, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 19, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 19, 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.