Patent US4141627A successfully refreshed from Google Patents.
US4141627A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-optic device
Assignee: RCA Corp
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Filing: 1977-01-06
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Granted: 1979-02-27
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Expires: 1997-01-06
Abstract
Abstract Novel dyes of the formula ##STR1## wherein X can be hydrogen, alkyl, alkoxy, cyano, nitro, dialkylamino, halogen or --N═N--Y and Y can be phenyl, phenyl substituted in the para position with an alkyl, alkoxy, cyano, nitro, dialkylamino or halogen group, or a heterocyclic ring, can be added to known liquid crystal compositions to impart color to the mixtures and improved contrast to a liquid crystal electro-optic device containing such mixtures.
Inventors
- 👤 Allen Bloom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:04
CPC Classifications
C; C09; C09B; C09B29/00; C09B29/0014; C09K; C09K19/00; C09K19/52; C09K19/60
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
71 words
In an electro-optic device comprising a nematic liquid crystal composition having a positive dielectric anisotropy between two electrodes, the improvement wherein said nematic liquid crystal composition contains a dye of the formula ##STR7## wherein X can be hydrogen, alkyl, alkoxy, cyano, nitro, dialkylamino, halogen or --N═N--Y and Y can be phenyl, phenyl substituted in the para position with an alkyl, alkoxy, cyano, nitro, dialkylamino or halogen group, or a heterocyclic ring.
Claim 2
Dependent Claim
71 words
In an electro-optic device comprising a nematic liquid crystal composition having a positive dielectric anisotropy between two electrodes, the improvement wherein said nematic liquid crystal composition contains a dye of the formula ##STR7## wherein X can be hydrogen, alkyl, alkoxy, cyano, nitro, dialkylamino, halogen or --N═N--Y and Y can be phenyl, phenyl substituted in the para position with an alkyl, alkoxy, cyano, nitro, dialkylamino or halogen group, or a heterocyclic ring.
Claim 3
Dependent Claim
26 words
A device according to claim 1 wherein X is methoxy and Y is ##STR8## wherein R can be hydrogen, alkyl, alkoxy, cyano, nitro, dialkylamino or halogen.
Claim 4
Dependent Claim
14 words
A device according to claim 1 wherein X is methoxy and Y is p-diethylaminophenyl.
Claim 5
Dependent Claim
60 words
A nematic liquid crystal composition comprising a nematic liquid crystal having a positive dielectric anisotropy and a compound of the formula ##STR9## wherein X can be hydrogen, alkyl, alkoxy, cyano, nitro, dialkylamino, halogen or --N═N--Y and Y can be phenyl, phenyl substituted in the para position with an alkyl, alkoxy, cyano, nitro, dialkylamino or halogen group, or a heterocyclic ring.
Claim 6
Dependent Claim
60 words
A nematic liquid crystal composition comprising a nematic liquid crystal having a positive dielectric anisotropy and a compound of the formula ##STR9## wherein X can be hydrogen, alkyl, alkoxy, cyano, nitro, dialkylamino, halogen or --N═N--Y and Y can be phenyl, phenyl substituted in the para position with an alkyl, alkoxy, cyano, nitro, dialkylamino or halogen group, or a heterocyclic ring.
Claim 7
Dependent Claim
26 words
A composition according to claim 4 wherein the nematic liquid crystal is a mixture of p-methoxybenzylidene-p'-n-butylaniline, p-ethoxybenzylidene-p'-n-butylaniline and one or more compounds having the formula ##STR10##
Claim 8
Dependent Claim
6 words
wherein R is an alkyl group.
Claim 9
Dependent Claim
6 words
wherein R is an alkyl group.
References Cited (Backward Citations)
US2400877A
Cited
US2544659A
Cited
US3597044A
Cited
US3703329A
Cited
US3864022A
Cited
US3833287A
Cited
US3960750A
Cited
US3960751A
Cited
US4032219A
Cited
US4025164A
Cited
US3957348A
Cited
DE2627215A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-26 | 1982-08-28 | 1983-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-26 | 1986-08-28 | 1987-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-26 | 1990-08-28 | 1991-02-27 | $7700.00 | Window Closed / Lapsed |