Amide functional ultraviolet light absorbers for polyurethanes and polyureas
CA 2305877 A1 · Owner: Minnesota Mining And Manufacturing Company · Inventors: Burns, David M.; Lasch, James E.; Olson, David B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An ultraviolet light absorbing materials that resists blooming and migration is made up of a polyurethane or polyurea polymer and an amide functional ultraviolet light absorbing compound, wherein the polymer and the amide functional ultraviolet light absorbing compound are hydrogen bonded to one another. Polymeric films that contain a polymeric matrix and the ultraviolet light absorbing material are useful as the top layer in multilayer constructions such a retroreflective sheetings and conformable marking sheets.
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 February 27, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 27, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 27, 2020.
- 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.