Microencapsulation of biologically active material
CA 1317223 C · Owner: Walch, Axel · Inventors: Keil, Karl-Heinz; Bader, Hubert; Walch, Axel
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the disclosure Polyelectrolyte membrane capsules are composed of a semipermeabLe membrane and an active material enclosed by it the membrane being formed of a biocompatible non-toxic, polyacid and a polybase; the polybase is composed of repeating monomer units of the formula (I) in which R1 and R2 have the indicated meanings.
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 May 4, 1993. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 4, 2010.
- 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.