Semipermeable membranes of copolyamides
CA 1102972 A · Owner: Bayer Aktiengesellschaft · Inventors: Bentz, Francis; Kunzel, Hans E.; Wolf, Gerhard D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Semipermeable membranes of copolyamides Abstract of the Disclosure, The invention relates to semipermeable membranes with a water absorption capacity of from 4.5 to 11. % by weight preferably from 4.5 to 8 % by weight, as measured on approximately 40 µ thick symmetrical films at room temperature and at 65 % relative air humidity a, throughflow of 130 to 200 l/m2d for a desalination level of 94.6 to 99.5 % and consisting of an aromatic heterocycle-containing copolyamide with a relative viscosity of ?1.4, as measured on a 0.5 % N-methyl pyrrolidone solution at a temperature of 20°C.
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
- Granted June 16, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 16, 1998.
- 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.