Episulfide compound, method for producing the same and optical product comprising same
CA 2406303 A1 · Owner: Takamatsu, Ken · Inventors: Takamatsu, Ken; Okubo, Tsuyoshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a novel episulfide compound useful as a starting material for optical materials that have a high refractive index and a high Abbe's number and to provide a method for efficiently producing the same and an optical product comprising the same. The episulfide compound represented by the general formula (1):, (see formula I), wherein EP represents (see formula II) and n is an integer of from 0 to 2, and the method for producing the episulfide compound represented by the general formula (1) comprises reacting a mercapto group-having episulfide compound with 2,4,6-trimethylene-1,3,5-trithiane.
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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 October 2, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 2, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 2, 2024.
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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.