Composite porous carbonaceous membranes
CA 2098684 C · Owner: Air Products And Chemicals, Inc. · Inventors: Sircar, Shivaji; Rao, Madhukar Bhaskara; Golden, Timothy Christopher
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Improved composite semipermeable membranes comprising microporous carbonaceous adsorptive material supported by a porous substrate are disclosed for use in separating multicomponent gas mixtures in which certain components in the mixture adsorb within the pores of the adsorptive material and diffuse by surface flow through the membrane to yield a permeate stream enriched in these components. Methods for making the improved composite membranes are described including one or more oxidation steps which increase the membrane permeability and selectivity.
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 17, 1993 and granted December 16, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 17, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 17, 2015.
- 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.