Stabilizers for halogen containing polymers
CA 2002256 A1 · Owner: Silbermann, Joseph · Inventors: Silbermann, Joseph; Smith, William L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Improved stabilizer compositions are provided which impart significant long-term heat stabilization to halogen-containing vinyl polymers such as polyvinyl chloride. The improved stabilizer compositions combine one or more metal-containing primary stabilizer compounds with a finely divided co-stabilizing phosphate material of a predetermined surface area. The phosphate material includes an anhydrous or hydrous sodium or potassium monohydrogen phosphate, lithium dihydrogen phosphate or, alkali-metal pyrophosphate. The novel combination of stabilizers enables a reduction in the amount of metalcontaining stabilizer, if desired, while still yielding long-term stability in the resultant polymer …
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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 November 6, 1989. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 6, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 6, 2011.
- 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.