Cycloolefin resin compositions
CA 2025021 C · Owner: Mitsui Petrochemical Industries, Ltd. · Inventors: Kasai, Tetsuji; Sakai, Hideki; Kawamoto, Keiji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The cycloolefin resin compositions of the present invention comprise a thermoplastic resin containing an olefin polymer having an alicyclic structure, specific stabilizers selected from phenolic stabilizers, organic thioether stabilizers, organic phosphite stabilizers UV-ray absorbers, and hindered amine stabilizers. The cycloolefin resin compositions show excellent thermal aging resistance and weathering resistance by the use of specific stabilizers and, therefore they are favorably used for forming optical instrument parts. Furthermore, the thermoplastic resin may be prepared from an olefin polymer having an alicyclic structure and a flexible polymer or flexible polymers. The …
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 January 12, 1990 and granted October 16, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 12, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 12, 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.