Copolyester of branched polyacetal for sliding member
CA 2043973 A1 · Owner: Polyplastics Co. Ltd. · Inventors: Sugiyama, Noriyuki; Sasaki, Katsushi; Ohachi, Yoshinori
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A copolymer of branched polyacetal for sliding member, which is obtained by polymerizing (A) 99.88 to 85.0 percent by weight of trioxane, (B) 0.1 to 10 percent by weight of a comonomer of a cyclic ether compound and/or a cyclic formal, such as ethylene oxide, dioxolan, trioxepane, and 1,4-butanediol formal and (C) 0.02 to 5 percent by weight of diglycidyl compound such as an alkylenoxide diglycidylether. The polymerization may be effected in the presence of an acetal compound having a low molecular weight defined, by the formula: RlO-(CH2O)nR2 in which Rl and R2 are independently an alkyl having 1 to 5 carbon atoms and n is 1 to 10. The copolymer is improved in resistance to abrasion and …
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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 June 5, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 5, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 5, 2013.
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Timeline
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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.