Non-linear optically active polycarbonate
CA 2133142 A1 · Owner: Wiersum, Ulfert E. · Inventors: Wiersum, Ulfert E.; Boonstra, Tjerk O.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure, The invention pertains to a non-linear optically active (NLO) side chain polycarbonate and to NLO active waveguides containing said polycarbonate. Waveguides containing this NLO polycarbonate have a low loss of signal. Polycarbonates based on bischloroformates of hexafluorobisphenol A hexafluorotetrabromobisphenol A and bisphenol S or deuterated bisphenol A or sulphonylbiphenol are especially preferred within the framework of the invention: they were found to give an exceptionally low loss of signal. The invention further pertains to cross-linkable and already cross-linked polycarbonates. Especially preferred polycarbonates according to the invention are those …
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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 September 28, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 28, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 28, 2016.
- 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.