Styrene copolymer and process for production thereof
CA 2027587 A1 · Owner: Kuramoto, Masahiko · Inventors: Tazaki, Toshinori; Kuramoto, Masahiko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A styrene copolymer which comprises a styrene repeating unit (a) represented by the general formula (I): ... (I), and an acrylonitrile repeating unit (b) represented by the general formula (II-(b)):, ... (II-(b)) unsaturated carboxylic acid or its ester repeating unit (c) represented by the general formula (II-(c)): ... (II-(c)), or maleimide or N-substituted maleimide (d) represented by the general formula (II-(d)):, ... (II-(d)) (in the formula, symbols are the same as defined in the specification), wherein stereoregularity of the styrene repeating unit (a) chain is a high degree of syndiotactic configuration is disclosed. - 54 -
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 March 20, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 20, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 20, 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.