Density element and method of manufacture thereof
CA 2013899 C · Owner: Alza Corporation · Inventors: Peery, John R.; Eckenhoff, James B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A density element (12) for use in ruminal delivery devices (10) which is manufactured by partial sintering in such a manner as to fragment upon contact with the many parts in rendering machinery without damage to the blades. The density element (12) has density of at least about 1.5 gm/cm3 and a transverse rupture strength greater than about 3000 psi (210 kg/cm2) no greater than about 30,000 psi (2120 kg/cm2). The part is sintered under conditions which do not permit full weld bond strength to be obtained and may thereafter be heat treated or impregnated with an inert hydrophobic material to increase corrosion resistance.
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 April 5, 1990 and granted April 4, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 5, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 5, 2012.
- 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.