Patent US4219256A successfully refreshed from Google Patents.
US4219256A
Expired / Lapsed
US
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Liquid crystal compounds and materials and devices containing them
Assignee: UK Secretary of State for Defence
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Filing: 1979-08-01
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Granted: 1980-08-26
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Expires: 1999-08-01
Abstract
Abstract A novel liquid crystal compound has the molecular structure: ##STR1## where R is an alkyl group, which may contain up to 18 carbon atoms and which may be normal or branched and may contain a chiral center, ##STR2## is a bicyclo (2.2.2) octane ring, ##STR3## is a phenyl ring and CN is a cyano group, n being an integer greater than 0 preferably 1 or 2. The compound may be used in mixtures with other liquid crystal compounds in the same or other families and the compound or mixtures may be used in known liquid crystal devices, eg the twisted nematic and cholesteric-to-nematic phase change devices, depending on its properties.
Inventors
- 👤 George M. Gray
- 👤 Stephen M. Kelly
- 👤 Damien G. McDonnell
- 👤 Alan Mosley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:49
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/32; C09K19/321
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
30 words
A liquid crystal compound having a molecular structure ##STR42## where R is an alkyl group and ##STR43## is a bicyclo (2.2.2) octane ring, n being an integer greater than zero.
Claim 2
Dependent Claim
30 words
A liquid crystal compound having a molecular structure ##STR42## where R is an alkyl group and ##STR43## is a bicyclo (2.2.2) octane ring, n being an integer greater than zero.
Claim 3
Dependent Claim
23 words
A liquid crystal compound as claimed in claim 1 and wherein R is an n-alkyl group having not more than 18 carbon atoms.
Claim 4
Dependent Claim
29 words
A liquid crystal compound as claimed in claim 1 and wherein R is a branched alkyl group having not more than 18 carbon atoms and containing a chiral centre.
Claim 5
Dependent Claim
26 words
A liquid crystal compound as claimed in claim 1 and wherein the integer n is one, the compound being a 1-[4' cyanophenyl]-4-alkyl substituted bicyclo [2.2.2] octane.
Claim 6
Dependent Claim
25 words
A liquid crystal compound as claimed in claim 1 and wherein the integer n is two, the compound being a 1-[4'-cyano-4"-biphenylyl]-4-alkyl substituted bicyclo [2.2.2] octane.
Claim 7
Dependent Claim
23 words
A liquid crystal compound as claimed in claim 4 and wherein R is an n-alkyl group having from 1 to 10 carbon atoms.
Claim 8
Dependent Claim
28 words
A liquid crystal compound as claimed in claim 4 and wherein R is an alkyl group having from three to 10 carbon atoms and containing a chiral centre.
Claim 9
Dependent Claim
23 words
A liquid crystal compound as claimed in claim 5 and wherein R is an n-alkyl group having from 1 to 10 carbon atoms.
Claim 10
Dependent Claim
28 words
A liquid crystal compound as claimed in claim 5 and wherein R is an alkyl group having from three to ten carbon atoms and containing a chiral centre.
Claim 11
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 6 and wherein the compound is ##STR44##
Claim 12
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 6 and wherein the compound is ##STR45##
Claim 13
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 6 and wherein the compound is ##STR46##
Claim 14
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 6 and wherein the compound is ##STR47##
Claim 15
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 6 and wherein the compound is ##STR48##
Claim 16
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 6 and wherein the compound is ##STR49##
Claim 17
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 6 and wherein the compound is ##STR50##
Claim 18
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 8 and wherein the compound is ##STR51##
Claim 19
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 8 and wherein the compound is ##STR52##
Claim 20
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 8 and wherein the compound is ##STR53##
Claim 21
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 8 and wherein the compound is ##STR54##
Claim 22
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 8 and wherein the compound is ##STR55##
Claim 23
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 8 and wherein the compound is ##STR56##
Claim 24
Dependent Claim
15 words
A liquid crystal compound as claimed in claim 8 and wherein the compound is ##STR57##
Claim 25
Dependent Claim
23 words
A liquid crystal compound material comprising a mixture of compounds at least one of which is a compound as claimed in claim 1.
Claim 26
Dependent Claim
21 words
A liquid crystal material comprising a mixture of compounds at least two of which are compounds as claimed in claim 1.
Claim 27
Dependent Claim
40 words
A liquid crystal material as claimed in claim 25 and wherein the mixture contains at least one compound of the form ##STR58## and at least one compound of the form ##STR59## where R' 1 and R' 2 are n-alkyl groups.
Claim 28
Dependent Claim
31 words
A liquid crystal material as claimed in claim 24 and wherein the mixture contains at least one compound of the form ##STR60## where R' 3 is an alkyl or alkoxy group.
Claim 29
Dependent Claim
72 words
An electro-optic liquid crystal device including two adjacent substrates at least one of which is optically transparent, a layer of liquid crystal material contained in the space between the substrates and, deposited on the inner facing surfaces of the substrates, a film of conducting material to allow an electric field to be applied across the layer and characterised in that the liquid crystal material includes a compound as claimed in claim 1.
Claim 30
Dependent Claim
19 words
A device as claimed in claim 28 and wherein the liquid crystal device is a twisted nematic effect device.
Claim 31
Dependent Claim
20 words
A device as claimed in claim 28 and wherein the liquid crystal device is a cholesteric-to-nematic phase change effect device.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-08-26 | 1984-02-25 | 1984-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-08-26 | 1988-02-25 | 1988-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-08-26 | 1992-02-25 | 1992-08-26 | $7700.00 | Window Closed / Lapsed |