High strength structural perlite concrete
CA 2033084 C · Owner: Williams, R. Steve · Inventors: Williams, R. Steve; Smetana, David A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A high strength concrete particularly useful for precast, prestressed products comprising by weight of the wet concrete mix, 8 to 60 percent cement, .5 to 20 percent smooth-surfaced, vesicular, expanded perlite 5 to 30 percent, water, 0 to 12 percent pozzolan and fine aggregate and, coarse aggregate as appropriate and available in the circumstances. The concrete provides superior bond to reinforcing strands. The smooth-surfaced, vesicular expanded perlite, is unique and novel.
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 May 18, 1990 and granted June 18, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 18, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 18, 2012.
- 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.