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US5143642A
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Liquid-crystalline medium for electrooptical display elements based on the ECB effect
Assignee: Merck Patent GmbH
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Filing: 1991-01-11
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Granted: 1992-09-01
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Expires: 2011-01-11
Abstract
Abstract The invention relates to a liquid-crystalline medium for electrooptical display elements based on the ECB effect, containing two components A and B which themselves comprise one or more individual compounds, component A having clearly negative dielectric anistropy and giving the liquid-crystalline phase a dielectric anistrophy of ≦-0.3, and component B having pronounced nematogeneity and a viscosity of not more than 30 mPa.s at 20° C., characterized in that component A contains one or more compounds containing a structural element ##STR1##
Inventors
- 👤 Joachim Krause
- 👤 Thomas Geelhaar
- 👤 Reinhard Hittich
- 👤 Ulrich Finkenzeller
- 👤 Bernhard Rieger
- 👤 Georg Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:47
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/04; C09K19/0403; C09K19/02; C09K19/0216; C09K19/06; C09K19/34; C09K19/3491; C09K19/3497; C09K19/42; C09K19/46; C09K2019/0414
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
71 words
A nematic liquid crystal medium which comprises a thiadiazole derivative of Formula I ##STR36## wherein p+q is 2, A.sup.° is 1,4-phenylene, one Z.sup.° group is --CH 2 CH 2 --, the other remaining Z.sup.° groups are single bons, and R 1 and R 2 are each, independently of one another, an alkyl group of up to 5 carbon atoms in which one --CH 2 -- group may be replaced by --O--.
Claim 2
Dependent Claim
71 words
A nematic liquid crystal medium which comprises a thiadiazole derivative of Formula I ##STR36## wherein p+q is 2, A.sup.° is 1,4-phenylene, one Z.sup.° group is --CH 2 CH 2 --, the other remaining Z.sup.° groups are single bons, and R 1 and R 2 are each, independently of one another, an alkyl group of up to 5 carbon atoms in which one --CH 2 -- group may be replaced by --O--.
Claim 3
Dependent Claim
28 words
A nematic liquid crystal medium as in claim 1, wherein the sum of the carbon atoms for R 1 +R 2 is from 2 to 8 carbon atoms.
References Cited (Backward Citations)
JPS5915254A
Cited
DE3703651A1
Cited
US4877549A
Cited
US4952699A
Cited
US5021189A
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EP0335348A2
Cited
US5034151A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-09-01 | 1996-03-02 | 1996-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-01 | 2000-03-02 | 2000-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-01 | 2004-03-02 | 2004-09-01 | $7700.00 | Window Closed / Lapsed |