Expired European patentEurope
Heterocyclically substituted ethanes and their use in liquid crystal materials and devices
EP 0152697 B1 · Applicant: Secretary of State for Defence in Her Britannic Majesty's Gov. of the United Kingdom of Great Britain and Northern Ireland
Overview
The published document from the EPO: abstract, claims, description and drawings. Open it full size
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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 December 31, 1984 and granted December 7, 1988. A European patent lasts at most 20 years from filing, so its term ended December 31, 2004.
- 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 July 1, 2010.
- 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.
FiledDecember 31, 1984
PublishedAugust 28, 1985
GrantedDecember 7, 1988
Term endedDecember 31, 2004
Application numberEP 84308931
Classification (CPC)C07C309/00 +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.