Tagging and identifying asphalt additives
CA 2114896 C · Owner: Caputo, Peter A. · Inventors: Hinton, Michael P.; Friswell, Michael R.; Zimin, Alejandro Sr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A tag is added to an asphalt additive, typically an anti-stripping agent. The tag is mixed with other components of an asphalt composition and melt processed at 300°F (149°C) or above to produce an asphalt composition. Presence of the tag to identify presence of the additive is performed by dissolving the asphalt portion of the composition in a water-immiscible solvent and then extracting the tag in an acidic aqueous solution and developing a color with a diazo compound.
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 3, 1994 and granted August 25, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 3, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 3, 2016.
- 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.