A durable porous article of manufacture and a process to create same
CA 2320641 C · Owner: Bischel, Marsha Stalker · Inventors: Putt, Dean L.; Bischel, Marsha Stalker; Moser, Andrea M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An acoustically absorbent porous panel formed from a cured aqueous foamed cementitious material comprising on a wet basis of about 53% to about 68% by weight cement about 17% to about 48% by weight water about 0.05% to about 5% by weight fiber and about 0.01 % to about 10% by weight surfactant. The panel also has pores distributed within the cured material comprising about 75% to about 95% by volume of the material. The cement-based foamed panel provides good acoustical performance with enhanced durability and moisture resistance.
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 September 26, 2000 and granted July 12, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 26, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 26, 2022.
- 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.