Hydroxypropyl methyl cellulose ethers useful as suspending agents for suspension polymerization of vinyl chloride and as thickening agents for organic liquids
CA 1280413 C · Owner: The Dow Chemical Company · Inventors: Hess, Roland H.P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Hydroxypropyl methyl cellulose ethers having methoxyl substitution of from 21 to 35 percent and hydroxypropoxyl substitution of from 15 to 35 percent are useful as suspending agents for the suspension polymerization of vinyl chloride to produce homoand copolymers of controlled particle size and high porosity. The hydroxypropyl methyl cellulose ethers having methoxyl substitution of from 21 percent to 35 percent and a hydroxypropoxyl substitution of from 18 to 30 percent and a number average molecular weight of at least 50,000 and those having a methoxyl substitution of greater than 24 percent are novel compounds. Hydroxypropyl cellulose ethers which have a methoxyl substitution of from 21 …
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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
- Granted February 19, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 19, 2008.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.