Uv stable polyvinyl butyral sheet
CA 2250411 C · Owner: Krach, Mary S. · Inventors: Krach, Mary S.; D'Errico, John J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Polyvinyl butyral , sheet for laminated safety glass containing multivalent, preferably divalent metal salt , and a UV-stabilizing amount of a benzotriazole-based compound , of formula (1) wherein R1 denotes CH3, linear or branched , C5 alkyl or linear or branched C12 alkyl and R2 denotes CH3 , or linear or branched C5 alkyl.
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 10, 1997 and granted March 8, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 10, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 10, 2019.
- 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.