Algae resistant roofing granules with controlled algaecide leaching rates, algae resistant shingles, and process for producing same
CA 2471215 C · Owner: Certainteed Corporation · Inventors: Hong, Keith C.; Kalkanoglu, Husnu M.; Shiao, Ming L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Algae-resistant roofing granules are formed by coating mineral particles with a clay-silicate binder including a metal oxide algaecide and small organic particles. When the particles are heated to cure the binder the organic particles pyrolyse to form pores in the coating. Release of the algaecide is controlled by the structure of the granules.
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 June 16, 2004 and granted October 30, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 16, 2024.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 16, 2026.
- 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.