Dental restorative material
CA 1269790 C · Owner: Pentron Corporation · Inventors: Waknine, Samuel
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a dental restorative material comprising 20-30% by weight of a visible light polymerizable methacrylic ester monomeric system, from about 65-79% by weight of an inorganic filler and from about 1-5% by weight of collidal fumed silica; said inorganic filler having an average particle size diameter ranging from about 0.5 to 5 microns and said collidal fumed silica having an average particle size ranging from about 0.01 to about 0.05 micron, the improvement comprising subjecting the filler to a series of milling steps comprising (1) wet milling in aqueous medium having a pH of 5-7; (2) surface etch milling in an aqueous etchant medium and (3) a silanizing milling in a silane solution.
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 29, 1990. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 29, 2007.
- 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.