Expired European patentEurope
Acetylene derivative, process for producing the same, liquid crystal composition containing the same as active ingredient, and liquid crystal element made therefrom
EP 0628530 B1 · Applicant: SUMITOMO CHEMICAL COMPANY LIMITED
Overview
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Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed October 26, 1993 and granted March 24, 1999. A European patent lasts at most 20 years from filing, so its term ended October 26, 2013.
- A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by April 26, 2019.
- We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.
FiledOctober 26, 1993
PublishedDecember 14, 1994
GrantedMarch 24, 1999
Term endedOctober 26, 2013
Application numberEP 93923059
Classification (CPC)C07C69/007 +2 more
Timeline
Timeline From EPO dates
Sources & verification
Official EPO records
Everything on this page comes from the EPO record linked above. EPO data used under CC BY 4.0.