Porous, absorbent, polymeric macrostructures and methods of making the same
CA 2078560 C · Owner: Roe, Donald Carroll · Inventors: Lahrman, Frank Henry; Berg, Charles John; Roe, Donald Carroll
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Absorbent polymeric macrostructures (52) that are porous and comprise an interparticle crosslinked aggregate having a circumscribed dry volume greater than about 10.0 mm3. The interparticle crosslinked aggregate comprises a multiplicity of precursor particles of substantially water-insoluble absorbent, hydrogel-, forming, polymer material; and an interparticle cross-linking agent reacted with the polymer material of the precursor particles to form crosslink bonds between the precursor particles. Because of the particulate nature of the precursor particles the , macrostructure (52) has pores between adjacent precursor particles. The pores are interconnected by intercommunicating …
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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 March 25, 1991 and granted November 30, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 25, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 25, 2013.
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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.